United States Patent | 6,246,561 |
Flynn | June 12, 2001 |
Charles Flynn's own website with more on his device"
A permanent magnet device includes a permanent magnet having north and south pole faces with a first pole piece positioned adjacent one pole face thereof and a second pole piece positioned adjacent the other pole face thereof so as to create at least two potential magnetic flux paths. A first control coil is positioned along one flux path and a second control coil is positioned along the other flux path, each coil being connected to a control circuit for controlling the energization thereof. The control coils may be energized in a variety of ways to achieved desirable motive and static devices, including linear reciprocating devices, linear motion devices, rotary motion devices and power conversion.
Inventors: | Flynn; Charles J. (Greenwood, MO) |
Assignee: | Magnetic Revolutions Limited, L.L.C (St. Louis, MO) |
Appl. No.: | 127056 |
Filed: | July 31, 1998 |
Current U.S. Class: | 361/147; 361/210 |
Intern'l Class: | H02K 021/12 |
Field of Search: | 361/143,147,206,210 |
FIG. 1 is a perspective view of a magnetic device in
which the magnetic flux from a magnetic member traverse a single path to produce
a coupling force;
FIG. 2 is a perspective view of a magnetic device in
which the magnetic flux from a magnetic member splits between two paths;
FIG. 3 is a side view of two magnetic members arrange in parallel
between pole pieces;
FIG. 4 is a side view of two magnetic members
arranged in series between pole pieces;
FIGS. 5-6 are side views of a
permanent magnet device including a permanent magnet having pole pieces
positioned against the pole faces thereof and including a movable armature;
FIGS. 7-9 are side views of a permanent magnet device including a
permanent magnet having pole pieces positioned against the pole faces thereof to
provide two magnetic flux paths and including a movable armature positionable
along each magnetic flux path;
FIGS. 10, 10A-10H are perspective views of various embodiments of permanent magnet 5 control components which include two or more magnetic flux paths;
FIGS. 11, 11A-11F are side views of a permanent magnet device including a permanent magnet having pole pieces positioned against the pole faces thereof and including a movable armature and a permanent bypass extending between the pole pieces;
FIGS. 12, 12A-12E
are side views of a two path permanent magnet device including two bypasses;
FIGS. 13A-13C are side views of a permanent magnet linear reciprocating
device;
FIG. 14 is a side view of an electromagnetic linear
reciprocating device;
FIG. 15 is a side view of a two path permanent
magnet device showing control coils energized in an exceeding manner;
FIGS. 16A-E are a side view of a linear reciprocating device with
control coils energized in an exceeding manner;
FIGS. 17A-17D depict
another embodiment of a linear reciprocating device;
FIGS. 18A-18E show
a linear motion device;
FIG. 19 is an exploded perspective view of a
rotary motion device;
FIG. 20 is a partial assembled and cut away view
of the rotary motion device of FIG. 19;
FIGS. 21A-21E are top views of
the partial assembly of FIG. 20, which views depict rotational motion thereof,
FIG. 22 is an assembled, cut-away view of the rotary motion device of
FIG. 19 including a housing;
FIG. 23 is an exploded perspective view of
another embodiment of a rotary motion device;
FIG. 24 is a perspective
view of the rotary motion device of FIG. 23 as assembled;
FIGS. 25A-25B
are end views of the rotary motion device of FIG. 24 with the end cap removed to
expose the rotor member;
FIGS. 26-28 show end views of various
configurations for skewing the direction of rotation in the rotary motion device
of FIG. 24;
FIG. 30
is an exploded partial perspective view of another embodiment of a rotary motion
device;
FIG. 31 is a perspective view of the rotary motion device of
FIG. 30 as assembled
FIGS. 32A-32D are top views of the rotary motion device of FIG. 31 illustrating rotational movement thereof;
FIG. 33 is a
side view of the rotary motion device of FIG. 31 as assembled and including a
housing;
FIG. 34 is a perspective view of another embodiment of a rotary
motion device;
FIG. 35 is a top view of the rotary motion device of FIG.
34;
FIG. 36 is a perspective view of the permanent magnet rotor member
of the rotary motion device of FIG. 34;
FIGS. 37 and 38 show alternative
configurations for the control component incorporated into the rotary motion
device of FIG. 34;
FIGS. 39A-39D are top views of the rotary motion
device of FIG. 34 and depict rotational movement thereof;
FIGS. 40-44
are alternative variations of circuit means for controlling the timed
energization of control coils in the various devices of the present invention;
FIGS. 45A-45C and 45X-45Z are side views of two path power conversion
devices;
FIG. 46 is a schematic view of the permanent magnet portion of
a rotor for use in some embodiments of the present device;
FIGS. 47 and
48 show other embodiments of a linear motion device;
FIG. 49 is a top
view of another embodiment of a rotating motor like construction; and
FIG. 50 is a schematic view of one of the three stator portions of the
device shown in FIG. 49.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, FIGS. 1-4 are provided to facilitate an
understanding of various aspects or features of the technology utilized in the
present invention. FIG. 1 depicts a device 10 having a magnetic flux producing
member 12 which may be a permanent magnet or electromagnet with magnetic poles
14 and 16 as shown. Pole pieces 18 and 20 are positioned adjacent respective
poles 14 and 16 to provide a path for the magnetic flux of member 12. Each pole
piece 18 and 20 includes a respective pole piece end face 22 and 24. As used
throughout this specification it is understood that a pole piece, regardless of
its shape or size, is preferably formed of soft iron, steel or some other
magnetic material, with the preferred material being one which provides low
reluctance, exhibits low hysterisis, and has a high magnetic flux density
capability. Accordingly, the various pole pieces disclosed and described herein
could likewise be of laminate type construction. Referring again to FIG. 1 an
armature 26, also formed of magnetic material, is shown with end faces 28 and 30
which are positioned and sized for being placed adjacent pole piece end faces 22
and 24, such that when so positioned a substantially continuous low reluctance
path 32 is provided for magnetic flux from north pole 14, through pole piece 18,
through armature 26, through pole piece 16, and to south pole 16. The magnetic
flux traveling along such path 32 results in a force which tends to hold
armature 26 in position adjacent pole piece end faces 22 and 24. The resulting
magnetic coupling or holding force F provided between adjacent pole piece end
face 22 and armature end face 28, and between adjacent pole piece end face 24
and armature end face 30, can be approximated by the following equation:
F=B.sup.2 A/2.mu..sub.0,
where B is the magnetic flux density
passing through the adjacent end faces and where A is the surface area of the
adjacent end faces. Assuming B uniform throughout flux path 32 and the area A of
all end faces 22, 24, 28, and 30 to be the same, the total holding force
F.sub.T26 of armature 26 against pole pieces 18 and 20 will be:
F.sub.T26 =B.sup.2 A/.mu..sub.0.
In FIG. 2 a device 40 having
the same magnetic flux producing member 12 with magnetic poles 14 and 16 is
shown. Pole pieces 42 and 44 are positioned adjacent respective pole faces 14
and 16 to provide two paths, as opposed to one above, for the magnetic flux of
member 12. In particular, pole piece 42 includes a first path portion 46
extending beyond a perimeter of north pole face 14 in one direction and a second
path portion 48 extending beyond the perimeter of north pole face 14 in another
direction. Similarly, pole piece 44 includes a first path portion 50 extending
beyond the perimeter of south pole face 16 in one direction and a second path
portion 52 extending beyond the perimeter of south pole face 16 in another
direction. Each pole piece path portion 46, 48, 50, 52 includes a respective end
face. A first armature 54 is positionable adjacent the end faces of pole piece
path portions 48 and 52 to provide a first magnetic flux path 56 and a second
armature 58 is positionable adjacent the end faces of pole piece path portions
46 and 50 to provide a second magnetic flux path 60. If the flux carrying area
along flux paths 56 and 60 is the same as the flux carrying area along flux path
32 of FIG. 1, the magnetic flux density along each flux path 56 and 60 will be
one-half the magnetic flux density along flux path 32 of FIG. 1 because the same
amount of flux is split between two like paths. The effect of dividing a given
amount of magnetic flux along two like flux paths instead of along one flux path
can be seen by examining the holding force on armature 54 as compared to the
holding force on armature 26 of FIG. 1. As already noted the magnetic flux
density along path 56 will be one-half that along flux path 32 and thus the
total holding force F.sub.T54 can be determined as:
F.sub.T54
=(B/2)2A/,.mu..sub.0 =B.sup.2 A/4.mu..sub.0 =F.sub.T26 /4.
It is
therefore seen that dividing the same amount of magnetic flux along two flux
paths rather than along one flux path reduces the magnetic holding or coupling
force on an armature by one-fourth rather than one-half as might have been
expected. This unexpected magnetic holding or coupling force differential,
resulting from multiple flux paths, can provide advantageous properties in
linear, reciprocating, and rotary motion devices.
Referring now to FIGS.
3-4, the behavior of multiple magnetic flux sources arranged in parallel and
series is described as compared to a single flux source. When identical flux
sources or magnetic flux producing members 70 and 72 are positioned in parallel
as shown in FIG. 3 with pole pieces 74 and 76 positioned adjacent the poles
thereof to provide a flux path through armature 78, the flux density B through
armature 78 is double what the flux density would be if only one magnetic flux
producing member were present. However, the field intensity H resulting from the
two members 70 and 72 remains unchanged. This result holds true regardless of
whether members 70 and 72 are both permanent magnets, are both electromagnets,
or are a combination of one permanent magnet and one electromagnet. On the other
hand, the properties resulting from magnetic flux producing members 80 and 82
arranged pole-to-pole in series between pole pieces 84 and 86, with armature 88,
as shown in FIG. 4, will vary depending on the nature of the members 80 and 82.
In a first case, if both members 80 and 82 are permanent magnets, the
magnetic field intensity H resulting from the two permanent magnets will be
double that of one permanent magnet and the flux density B through armature 88
will be the same as what the flux density would be if only one permanent magnet
type member were present.
In a second case, if both members 80 and 82
are electromagnets, the field intensity H again doubles and the flux density B
increases according to the B/H curve or relationship of the pole piece 84, 86
and armature 88 materials.
In a third case, if member 80 is a permanent
magnet and member 82 is an electromagnet, the field intensity H again doubles,
but, since the permanent magnet is near flux density saturation B.sub.r the flux
density can only be increased from B.sub.r to B.sub.max of the permanent magnet.
At the point where electromagnet-type member 82 contacts permanent magnet-type
member 80 the flux from the electromagnet-type member 82 couples with the flux
of the permanent magnet-type member 82 until the flux density through permanent
magnet-type member 80 reaches B.sub.max. At that point additional flux from
electromagnet-type member 82 does not contribute to the flux density along the
flux path unless a bypass path around the permanent magnet-type member is
provided. Use of such bypass paths will be described hereinbelow.
Controlling the flow of flux along both one and multiple flux paths is
best described with reference to FIGS. 5-9. In FIGS. 5 and 6 a permanent magnet
device 90 including a permanent magnet 92 having pole pieces 94 and 96
positioned adjacent the pole faces thereof and an armature 98 completing a low
reluctance path 104 from pole to pole is shown. Control coils 100, 102 are
positioned along path 104. When control coils 100, 102 are not energized, the
magnetic flux of permanent magnet 92 follows path 104 as shown and armature 98
is held in place against pole pieces 94, 96 due to the resulting magnetic
coupling forces. However, if coils 100, 102 are energized to provide an equal
but opposing magnetic flux to that of permanent magnet 92, the result is that
the magnetic flux of permanent magnet 92 is blocked and no magnetic flux
traverses the path which includes armature 98 and therefore no magnetic coupling
forces act on armature 98 allowing it to fall away as shown in FIG. 6. The
permanent magnet device 90 is useful, although as will become apparent below, it
is more advantageous to provide multiple flux paths rather than one.
In
this regard, in FIG. 7 a permanent magnet device 110 includes a permanent magnet
112 having pole pieces 114, 116 positioned adjacent the pole faces thereof with
armatures 118, 120 completing two low reluctance paths 130, 132 from pole to
pole thereof. Control coils 122, 124 are positioned along path 130 and control
coils 126, 128 are positioned along path 132. The two paths provided are assumed
to be of equal reluctance. With no coils energized, the magnetic flux of
permanent magnet 112 divides equally along flux path 130 and along flux path 132
such that both armatures 118, 120 are subjected to a magnetic coupling force
which holds them in place against pole pieces 114, 116.
If coils 122,
124 are energized to provide a magnetic flux equal to but opposing the magnetic
flux which travels along flux path 130 from permanent magnet 112 when no coils
are energized, the result is that the magnetic flux of permanent magnet 112 is
blocked and no magnetic flux traverses the path which includes armature 118 and
therefore no magnetic coupling forces act on armature 118 allowing it to fall
away as shown in FIG. 8. Further, the magnetic flux traversing path 132 will be
double that of when no coils are energized and therefore the magnetic coupling
force on armature 120 will be about four (4) times that of when no coils are
energized. By energizing coils 126, 128 in an opposing manner a similar result
would be achieved such that armature 120 would fall away and such that the
magnetic coupling force on armature 118 would be increased.
If coils
122, 124 are energized to provide a magnetic flux equal to and aiding the
magnetic flux which travels along flux path 130 when no coils are energized, the
result is that the control coils couple completely with the magnetic flux of
permanent magnet 112 and no magnetic flux traverses the path which includes
armature 120 and therefore no magnetic coupling forces act on armature 120
allowing it to fall away as shown in FIG. 9. Further, the magnetic flux
traversing path 130 will be double that of when no coils are energized and
therefore the magnetic coupling force on armature 118 will be about four (4)
times that when no coils are energized. By energizing coils 126, 128 in an
aiding manner a similar result would be achieved such that armature 118 would
fall away and the magnetic coupling force on armature 120 would be increased.
Based on the foregoing it is seen that the full magnetic coupling force
available from the permanent magnet 112 can be switched from one path to another
path by the application of one half the power it would require for a coil alone
to produce the same magnetic flux along one path. The ability to easily switch
the full magnetic coupling force from one path to another allows for efficient
reciprocating, linear, and rotary motion and power conversion to be achieved.
The basic device utilized to achieve permanent magnet flux division and
to control such permanent magnet flux division is defined herein as a "permanent
magnet control component," various configurations of which are shown by way of
example only, and not by way of limitation, in FIGS. 10A-10F. FIG. 10A depicts a
permanent magnet control component 150 in which pole pieces 152 and 154 are
positioned adjacent the pole faces of permanent magnet 156 to provide two
magnetic flux paths extending from opposite sides of permanent magnet. Control
coils 158 are positioned along each path. FIG. 10B depicts a permanent magnet
control component 160 in which pole pieces 162 and 164 are positioned against
the pole faces of permanent magnet 166 to provide two spaced, adjacent magnetic
flux paths extending from the same side of permanent magnet 166. Control coils
168 are positioned along each path. FIG. 10C depicts a permanent magnet control
component 170 in which pole pieces 172 and 174 are configured so as to be
positioned adjacent the pole faces of permanent magnet 176 so as to provide four
flux paths, each flux path extending in a respective direction from permanent
magnet 176. Control coils 178 are also positioned along each path. FIG. 10D
depicts another four path configuration of a permanent magnet control component
180 in which pole pieces 182, 184 are configured and positioned to provide four
flux paths for permanent magnet 186, with a pair of spaced, adjacent flux paths
extending from each side of permanent magnet 186. Control coils 188 are
positioned along each path. FIG. 10E depicts another four path configuration of
a permanent magnet control component 190 in which all four flux paths formed by
pole pieces 192, 194 extend from one side of permanent magnet 196. Again,
control coils 198 are positioned along each flux path. FIG. 10F still further
depicts a four path configuration of a permanent magnet control component 200 in
which pole pieces 202, 204 extend to one side of permanent magnet 206, with pole
piece 202 defining four flux paths and with pole piece 204 including a
continuous return path. Control coils 208 are positioned along each path of pole
piece 202. Many other variations are possible.
Accordingly, it is seen
that a variety of different configurations of permanent magnet control
components in accordance with the present invention are possible. The important
considerations for division of permanent magnet flux in such permanent magnet
control components include extending each pole piece to or beyond the outer
perimeter of the pole face of the permanent magnet in each region where a flux
path is intended and assuring that the pole face of the permanent magnet
intersects each of the flux paths. It is not necessary for each pole piece to
include the same number of path portions extending beyond the perimeter of the
respective permanent magnet pole face as noted with reference to permanent
magnet control component 200. Although two control coils are shown along each of
the flux paths in FIGS. 10A-10E it is apparent from component 200 in FIG. 10F
that one control coil positioned along a flux path is generally sufficient for
purposes of the present invention. Further, although in the illustrated
configurations each pole piece is positioned to contact a respective pole face
of the permanent magnet, a small spacing between a pole piece and its adjacent
permanent magnet pole face could be provided, particularly in applications where
relative movement between the subject pole piece and the permanent magnet will
occur.
In its simplest form a two path permanent magnet control
component only requires one control coil positioned along one of the control
paths to permit the magnetic flux of a permanent magnet to be switched between
the two paths. In particular, a side view of such a two path component 210 is
shown in FIG. 10G and includes a permanent magnet 211 pole pieces 212 and 213,
and control coil 214 which may be connected to a suitable control circuit. By
alternating energizing control coil 214 in an opposing manner and an aiding
manner the magnetic flux of permanent magnet can be switched between the path
including armature 215 and the path including armature 216. When control coil
214 is energized in an opposing manner the magnetic flux will traverse the path
including armature 215 and when control coil 214 is energized in an aiding
manner the magnetic flux will traverse the path including armature 216. Control
coil 214 could also be placed at anyone of positions 217, 218, or 219 to achieve
the flux path switching. Further, in the two coils embodiment shown in FIG. 10H
control coil 217 is added. In such a device flux switching can be achieved by
simultaneously energizing control coil 214 in a flux aiding manner and control
coil 217 in a flux opposing manner, and by then simultaneously reversing the
energization of the respective control coils 214 and 217.
Reference is
made to FIGS. 11A-11F which depict devices similar to that of FIGS. 5-6 except
that a bypass, formed of magnetic material, is provided in each case. In device
220 of FIGS. 11A-11C a bypass 222 is provided from pole piece 224 to pole piece
226 and is located between permanent magnet 228 and control coils 230, 232, with
armature 234 located adjacent the ends of pole pieces 224, 226. In FIG. 11A with
no coil energization, magnet flux components 236 and 237 travel as shown. When
coils 230 and 232 are energized in an aiding or adding manner as in FIG. 11B,
the result is permanent magnet magnetic flux components 236 and 237 traveling as
shown, and with the added magnetic flux component 238 from coils 230 and 232
also traveling as shown. Thus, in device 220 energizing the coils in an aiding
manner results in an increased magnetic coupling force on armature 234. In FIG.
11C coils 230, 232 are energized in an opposing exceeding manner which results
in permanent magnetic flux components 236 and 237 traveling as shown and excess
magnetic flux component 238 traveling as shown. Thus, in device 220 energizing
the coils in an opposing exceeding manner results in magnetic coupling force on
armature 234, albeit smaller than that in the aiding exceeding case.
In
device 240 of FIGS. 11D-11F a bypass 242 is provided between pole piece 244 and
pole piece 246 but is located on an opposite side of permanent magnet 248 as
compared to control coils 250, 252 and armature 254. Permanent magnet flux
components 256 and 257 are shown for no coil energization in FIG. 11D. In FIG.
11E the paths of permanent magnet flux components 256 and 257, as well as excess
coil magnetic flux 258, are shown when coils 250, 252 are energized in an aiding
exceeding manner. In FIG. 11F the path of each magnetic flux component 256, 257,
and 258 is shown when coils 230, 232 are energized in an opposed exceeding
manner.
FIGS. 12A-12E depict a device 270 similar to that shown in FIGS.
7-9 except that bypasses 272 and 274 are provided from pole piece 276 to pole
piece 278. Bypass 272 is located between permanent magnet 280 and control coils
282, 284 and bypass 274 is located between permanent magnet 280 and control
coils 286, 288. Armatures 290 and 292 are also provided. When no coils are
energized permanent magnet magnetic flux components 294, 296, 298, and 300
travel as shown in FIG. 12A.
If coils 282, 284 are energized in an
opposing manner permanent magnet flux components 295, 297, and 299 travel as
shown, with no flux component traversing the path which includes armature 290
and therefore no magnetic coupling force acting thereon. This would be the case
for when coils 282, 284 are energized to the level where the coils magnetic flux
just blocks, but does not exceed, the magnetic flux component 294 (FIG. 12A)
from permanent magnet 280. If, however, coils 282, 284 are energized in an
opposed exceeding manner an excess coil magnetic flux component 301 is produced
which travels a path including armature 290 and bypass 272 results as shown in
FIG. 12C.
Coils 286, 288 may be energized in an aiding manner such that
all permanent magnet magnetic flux travels along the path which includes
armature 292 as shown in FIG. 12D. If coils 286, 288 are energized in excess of
the level of FIG. 12D then the excess magnetic flux component 304 traverses the
path which includes armature 292 and bypass 274 as shown in FIG. 12E, thereby
increasing the magnetic coupling force on armature 292 as compared to FIG. 12D.
The advantage of incorporating such bypasses into permanent magnet control
components in certain applications will become apparent below.
Reciprocating Motion
As mentioned above, controlling the path of
magnetic flux from a permanent magnet can be useful in a variety of applications
such as achieving reciprocating motion. In this regard, if the device 110 of
FIGS. 7-9 is modified such that armatures 118 and 120 are fixed to a sliding
shaft 320 as shown in FIGS. 13A-13C, and if the distance between the armatures
is greater than the end to end length of pole pieces 114, 116, limited linear
motion in two directions (left and right in FIGS. 13A-13C), and therefore linear
reciprocating motion, can be achieved by the timed, alternate delivery of
electrical signals to control coils 122, 124 and control coils 126, 128. By way
of example, FIG. 13A represents the position of shaft connected armatures 118,
120 when coils 122, 124 are energized in an opposing manner to block the flux of
permanent magnet 112 such that all magnetic flux traverses path 132 as shown and
such that the resulting magnetic coupling force acts to the left as indicated by
arrow 322. As shown in FIG. 13B when coils 122, 124 are de-energized the
magnetic flux from permanent magnet 112 can again travel along path 130 through
armature 118. However, due to the air gap 324 between armature 118 and pole
pieces 114, 116 the reluctance along path 130 will be significantly greater than
the reluctance along path 132. Accordingly, the amount of magnetic flux which
flows along path 130 will be less than the amount of magnetic flux which flows
along path 132 such that the magnetic coupling force on armature 118 acting to
the right will be significantly less than the magnetic coupling force on
armature 120 acting to the left as shown by arrows 326 and 328, which arrows are
sized to represent the strength of the respective directional force. FIG. 13C
represents the position of shaft connected armatures 118, 120 after coils 126,
128 are energized in a manner to oppose the flux of permanent magnet 112 such
that all flux traverses path 130 and the resulting magnetic coupling force on
armature 118, depicted by arrow 330, moves the shaft 10 connected armatures 118,
120 to the right.
Control coils 122, 124 and 126, 128 could also be
energized in a flux aiding manner to achieve the same result. In such a device,
FIG. 13A would represent coils 126, 128 energized to aid magnetic flux along
path 132, FIG. 13B would again represent no coils energized, and FIG. 13C would
represent coils 122, 124 energized to aid magnetic flux along path 130.
Thus, by alternatingly energizing and de-energizing control coils 122,
124 and 126, 128 a linear reciprocating motion of shaft connected armatures 118,
120 may be achieved. Further, such reciprocating motion may be achieved by
energizing the coils in either an opposing or aiding manner. The magnetic
coupling force exerted on a given armature when 20 the control coils are
energized to establish all magnetic flux along a single path which includes that
armature is significantly greater than the magnetic coupling force which would
be exerted on such armature by an identical energization of the control coils in
the absence of the permanent magnet. This is demonstrated with reference to FIG.
14 which depicts a reciprocating device 340 in which only coils or
electromagnets are utilized. As shown armatures 342 and 344 are connected by
shaft 346, and each armature 342, 344 includes a respective U-shaped pole path
piece 348, 350 which pole path pieces are mechanically connected by a
non-magnetic material 352. Each pole path piece 348 and 350 has respective
control coils 354, 356 and 358, 360 positioned therealong. By comparison with
the device of FIGS. 13A-13C, if coils 358, 360 of device 340 are energized to
cause magnetic flux flow in either direction, clockwise or counterclockwise,
along path 362, the amount of electrical energy which would be required in order
to achieve the same magnetic coupling force on armature 344 as achieved on
armature 120 above in FIG. 13A would be twice that delivered to coils 122, 124
or 126, 128 in FIG. 13A. It is therefore demonstrated that by controlling or
switching the flow of magnetic flux from a permanent magnet between at least two
different paths results in greater coupling forces per unit of input electrical
energy, and therefore that such control or switching will enable more work to be
achieved per unit of input electrical energy.
As described above, if a
coil is energized beyond the point where the magnetic flux produced by the coil
aiding the amount of the permanent magnet's flux that is either opposed or
aided, the extra magnetic flux needs a low reluctance path between the poles of
the coil that produces the excess magnetic flux. If a complete low reluctance
path is not provided for the excess magnetic flux there is little potential for
taking advantage of the excess magnetic flux in terms of producing additional
magnetic coupling forces. The path for such excess flux cannot be through a
permanent magnet member. In assemblies which include an armature on each path,
the armature will provide the necessary low reluctance path. Referring to FIG.
15, various components of the magnetic flux in device 110 (FIGS. 7-9) are
depicted by numerals 380, 382, and 384 for the case when coils 122, 124 are
energized to oppose the magnetic flux of permanent magnet 112 in an amount which
exceeds the level of magnetic flux which permanent magnet 112 would cause to
flow through armature 118 when no coils are energized. FIG. 15 is likewise
representative of the case when coils 126, 128 are energized to aid the magnetic
flux of permanent magnet 112 in an amount which exceeds the level of magnetic
flux which permanent magnet 112 would cause to flow through armature 118 when no
coils are energized. In particular, magnetic flux component 380 represents the
magnetic flux of permanent magnet 112 which normally flows through the path
including armature 120; magnetic flux component 382 represents the magnetic flux
of permanent magnet 112 which is diverted by the opposing field of coils 122,
124 so as to traverse the path which includes armature 120; and magnetic flux
component 384 represents the magnetic flux produced by coils 122, 124 which is
in excess of the diverted magnetic flux 382. As shown, the excess magnetic flux
384 produced by coils 122, 124 traverses the path which includes armature 120
and bypasses permanent magnet 112 so as to also traverse the path which includes
armature 118. Thus, the excess magnetic flux produced by coils 122, 124 adds to
the permanent magnet flux traversing the path which includes armature 120, thus
increasing the magnetic coupling force on armature 120, while at the same time
providing a magnetic coupling force on armature 118.
In a reciprocating
device where armatures 118 and 120 are connected by shaft 320 as shown in FIGS.
13A-13C and again in FIG. 16, excess magnetic flux 384 will increase magnetic
coupling force 390 on armature 120 acting to the left. However, because such
excess flux 384 also traverses the path which includes armature 118, such excess
magnetic flux 384 also results in a magnetic coupling force 392 on armature 118
which acts to the right. Even though excess magnetic flux 384 traversing the
path which includes an armature 118 has an opposite polarity to that which would
traverse the path due to permanent magnet 112, the magnetic coupling force on
armature 118 still acts to the right because armature 118 is not polarity
sensitive, that is, armature 118 will be attracted regardless of the direction
of the magnetic flux traversing the path. The overall effect is that a resultant
force which is the difference between force 390 and force 392 will act on the
shaft-connected armatures 118, 120. However, if armatures 118 and 120 were
formed by permanent magnets having polarities as shown at the top and bottom of
such armatures, the force acting on each armature would be in the same direction
and therefore additive.
In this regard reference is made to FIG. 16B in
which a two path device 371 having four control coils 373, 375, 377 and 379 is
shown with the illustrated armatures being formed by permanent magnets 381 and
383 having polarities as shown. With no coils energized both permanent magnet
armatures 381 and 383 are attracted to the ends of pole pieces 385 and 387. With
coils 373375 energized in an opposing manner and coils 377, 379 energized in an
aiding manner, the attractive force on permanent magnet armature 383 will
generally increase and the attractive force on permanent magnet armature 381
will generally decrease. This is demonstrated with reference to the graph of
FIG. 16C which depicts a graph of the current flowing in the control coils on
the x-axis verses the magnetic flux in gauss on the y-axis with line 389
representing the flux along the aiding side of device 371 and line 391
representing the flux along the opposing side of device 371. As shown the
magnetic flux on the coil opposing side decreases as the coil current increases
and passed through zero at point 393. After point 393 reverse magnetic flux
begins to be produced and would result in a repelling force on permanent magnet
armature 381. In some applications particularly those where permanent magnet
armatures and rotors are not utilized, it will be critical to recognize point
393 so that reverse magnetic flux is not produced. In this regard reference is
made to FIGS. 16D and 16E in which use of Hall Effect switches 401 and 403 is
incorporated to enable controlling the coil energizing current in situations
where it is desirable to prevent reverse magnetic flux. As shown small bypasses
405 and 407 are provided with Hall Effect switches 401 and 403 disposed in gaps
therealong, the switches being connected to control circuit 409. As the flux
traveling along the bypass path falls to zero the Hall Effect switch can be
utilized to prevent further energization of the control coils so that no reverse
flux is created.
Another embodiment of a device 400 which would provide
reciprocating motion is shown in FIGS. 17A-17D in which a permanent magnet
control component 402 having two flux paths may is provided. A first pole piece
404 has two spaced, adjacent path portions 406 and 408 extending beyond the
perimeter of the pole face of permanent magnet 410, and a second pole piece 412
includes only one continuous portion 414 extending beyond the perimeter of the
pole face of permanent magnet 410, each path portion 406 and 408 of pole piece
404 being substantially aligned with at least a part of portion 414 of pole
piece 412. Control coil 416 is positioned along pole piece path portion 406 and
control coil 418 is positioned along pole piece portion 408. An armature 420 is
positioned in the region between pole piece path portions 404, 406 and pole
piece portion 414 and is free to slide from side to side as shown by arrows 422
and 424. A front view of component device 400 with no coils energized and
armature 420 at a mid-point depicts flux flowing from the north pole face of
permanent magnet 410, through each of pole piece path portions 406 and 408,
through armature 420, and returning to the south pole face through pole piece
portion 414. Thus, the magnetic flux divides equally along two paths. If coil
416 is energized in an aiding manner, or if coil 418 is energized in an opposing
manner, all or a majority of the permanent magnets'magnetic flux can be made to
flow through pole piece portion 406 such that a resulting magnetic coupling
force on armature 420 causes it to move to the left as shown in FIG. 17C.
Likewise, if control coil 416 is energized in an opposing manner, or if
control coil 418 is energized in an aiding manner, all or a majority of the
permanent magnet flux can be made to flow through pole piece path portion 408
such that a resulting magnetic coupling force on armature 420 causes it to move
to the right as shown in FIG. 17D. Accordingly, by alternately energizing and
de-energizing coils 416 and 418 a reciprocating motion of armature 420 may be
achieved.
Linear Motion
Referring now to FIGS. 18A-18E, linear
motion in accordance with the present invention is described. In particular, a
permanent magnet control component 440 including a permanent magnet 442 with a
pole piece 444 positioned against the north pole face thereof and a pole piece
446 positioned against the south pole face thereof is shown in an exploded view
in FIG. 18A and assembled in FIG. 18B. Pole piece 444 includes five path
portions 448A-448E which extend beyond the perimeter of the north pole face of
permanent magnet 442 to one side thereof and at respective positions along the
length thereof, each path portion 448A-448E including a respective control coil
450A-450E positioned therearound. Pole piece 446 includes one portion 452
extending beyond the perimeter of the south pole face of permanent magnet 442 to
the one side thereof, which portion 452 extends along the entire length of
permanent magnet 442. A plurality of armatures 454 define a path of relative
movement between permanent magnet control component 440 and such armatures 454,
and by providing timed energization of given control coils 450A-450E such
relative movement can be achieved. The sequence of side views depicted in FIGS.
18C-18E illustrate such relative movement, with coils 450A, 450C and 450E being
energized in an opposing manner simultaneously in FIG. 18C, with coils 450A and
450D being energized simultaneously in an opposing manner in FIG. 18D, and with
coils 450B and 450D being energized simultaneously in an opposing manner in FIG.
18E. In FIG. 18C, magnetic flux will only flow along path portions 448B and 448C
of pole piece 444 causing resultant magnetic coupling forces depicted by arrows
456, 458 which act to move permanent magnet control component 440 to the left,
assuming armatures 454 are fixed. Similarly, due to the timing of subsequent
coil energization resultant magnetic forces depicted by arrows 460, 462 in FIG.
18D and arrows 464, 466 in FIG. 18E act to continue movement of permanent magnet
control component 440 to the left. Thus, if permanent magnet control component
440 were fixed to a device or structure, controlled movement of the device or
structure along the path defined by armatures 454 could be achieved. Conversely,
if permanent magnet control component 440 were fixed and armatures 454 were
located on a device or structure, controlled movement of the device or structure
could also be achieved. It is also easily recognized that by varying the coil
energization sequence and timing relative movement in the opposite direction can
be achieved. Further, if the permanent magnet was doughnut shaped and the
armatures were arranged in a circumferential pattern, rotary motion would
likewise be achievable.
Rotary Motion
One embodiment of a rotary
motion device or motor 500 which incorporates various permanent magnet flux
control aspects of the present invention is shown in the exploded view of FIG.
19 and in the partial assembled view of FIG. 20. Motor 500 includes a rotor
assembly which includes a shaft 502 and associated upper bearing 504, a
non-magnetic disk member 506 mounted for rotation with shaft 502, and a rotor
pole piece 508 which is mounted for rotation with disk member 506 such as by the
use of screws 510. Rotor pole piece 508 includes a ring-shaped portion having
two inwardly extending magnetic flux path portions 512A and 512B. A stator
assembly of motor 500 includes a doughnut or ring-shaped permanent magnet 514
having an upwardly directed north pole face positioned adjacent and in close
proximity to rotor pole piece 508, and a downwardly directed south pole face
positioned adjacent and in contact with a stator pole piece 516. Stator pole
piece includes a ring-shaped portion having five inwardly projecting path
portions 518A-518E. Each path portion includes a respective winding post
520A-520E extending therefrom and having a respective control coil 522A-522E
wound thereon. Stator pole piece faces 524A-524E are positionable on respective
winding posts 518A-518B and, as shown in the partial assembly of FIG. 20, are
substantially aligned with the top surface of permanent magnet 514 so as to be
positionable adjacent rotor path portions 512A and 512B when aligned therewith.
Each of winding posts 518A-518E and stator pole piece faces are formed of
magnetic material, and although shown as separate pieces, an integral, one piece
stator could be formed with similar winding posts and pole piece faces machined
thereon. Lower bearing 526 is also shown.
FIGS. 21A-21E illustrate top
views of the partial assembly of FIG. 20 with magnetic flux shown. In FIG. 21A
magnetic flux travel when none of coils 522A-522E are energized is depicted.
Disregarding leakage flux, due to the low reluctance path provided by rotor pole
piece path portions 512A and 512B, the majority of magnetic flux from the north
pole face of permanent magnet 514 will travel radially inward along one of such
path portions before passing downward through the stator assembly and returning
to the south pole face of permanent magnet 514. It is noted that rotor pole
piece 508 includes two path portions and stator pole piece 516 includes five
path portions such that rotor pole piece path portions 512A and 512B will always
be skewed relative to the stator pole piece faces 524A-524E. Only one rotor pole
piece path portion can directly align with a stator pole piece face at a given
time. By alternatingly energizing the control coils of each of the stator pole
piece paths, rotary motion of the rotor may be achieved.
In particular,
referring to FIGS. 21B-21D, an energizing sequence which results in such rotary
motion is described. In FIG. 21B, control coils 522A and 522C are energized in a
permanent magnet flux opposing manner. Permanent magnet magnetic flux traveling
along rotor pole piece path portion 512A tends to traverse to stator pole piece
face 524B causing a magnetic coupling force indicated by arrow 526. Likewise,
permanent magnet flux traveling along rotor pole piece path portion 512B tends
to traverse to stator pole piece face 524D causing a magnetic coupling force
indicated by arrow 528. The result is rotation of rotor pole piece 508 in a
clockwise direction as indicated by arrow 530.
Referring to FIG. 21C,
just after rotor pole piece path portion 512B is no longer aligned with stator
pole piece face 524D, control coil 522C is de-energized and control coil 522D is
energized in an opposing manner such that the permanent magnet flux traveling
along rotor pole piece path 512B tends to traverse to stator pole piece face
524E resulting in magnetic coupling force indicated by arrow 532. Control coil
522A remains energized such that a magnetic coupling force indicated by arrow
534 results. Accordingly, clockwise rotation of rotor pole piece 508 is
continued.
In FIG. 21D, just after rotor pole piece path portion 512A is
no longer aligned with stator pole piece face 524B, control coil 522A is
de-energized and control coil 522B is energized in a permanent magnet magnetic
flux opposing manner such that the permanent magnet magnetic flux traveling
along rotor pole piece path 512A tends to traverse to stator pole piece face
524C such that a magnetic coupling force indicated by arrow 536 results. Control
coil 522D remains energized such that a magnetic coupling force indicated by
arrow 538 results, and clockwise rotation of rotor pole piece 508 is continued.
As shown in FIG. 21E, just after rotor pole piece path portion 512B is
no longer aligned with stator pole piece face 524E, control coil 522D is
de-energized and control coil 522E is energized in a permanent magnet magnetic
flux opposing manner such that the permanent magnet magnetic flux traveling
along rotor pole piece path 512B tends to traverse to stator pole piece face
524A such that a magnetic coupling force indicated by arrow 540 results. Control
coil 522B remains energized such that a magnetic coupling force indicated by
arrow 542 results, and clockwise rotation of rotor pole piece 508 is continued.
Thus, by alternating energizing and de-energizing control coils
522A-522E, in a predetermined timed sequence based upon rotation of the rotor
assembly, continued rotation movement of rotor pole piece 508 may be achieved.
Such an energization/de-energization scheme can be achieved utilizing circuitry
common in the art, such as the control circuitry described in Applicant's U.S.
Pat. Nos. 5,463,263 and 5,455,474, as well as various of the circuit
configurations described herein below. Referring now to FIG. 22, an assembled
view of rotary motor 500 is shown including a housing or cover formed by an
upper housing member 544 and a lower housing member 546, with portions of each
housing member cut away to expose motor structure described above. It is
recognized that such housing members 544 and 546 should be formed of a
non-magnetic material, and likewise that motor shaft 502 and bearings 504, 526
should be formed of a non-magnetic material.
In another embodiment, a
rotary motion device or motor 580 in accordance with the present invention is
shown in an exploded perspective view in FIG. 23 and in an assembled perspective
view in FIG. 24. Two spaced permanent magnets 582 and 584 are positionable
between stator pole pieces 586 and 588. Stator pole piece 586 includes two path
portions 590A and 590B extending away from permanent magnets 582, 584 in
opposite directions. Likewise, stator pole piece 588 includes two path portions
592A and 592B extending away from permanent magnets 582, 584 in opposite
directions and alignable respectively with stator pole piece path portions 590A
and 590B. Control coils 594, 596, 598, and 600 are each positioned along a
respective stator pole piece path portion as shown. A non-magnetic shaft 602
includes a pair of like elongated rotor members 604 and 606, formed of magnetic
material, mounted at spaced locations thereon and being angularly oriented with
respect to each other, shaft 602 passing between spaced permanent magnets 582
and 584. Non-magnetic end cap members 608 and 610 are attachable to the ends of
stator pole pieces 586 and 588 and are configured for receiving shaft 602 and
respective bearings 612 and 614.
The ends of respective stator pole
pieces 506 and 508 are configured for a given desired coupling relationship with
rotor members 604 and 606. For example, as shown in the exemplary end views of
FIGS. 25A and 25B, with end cap 608 removed, the end of stator pole piece 586
may include an arcuate portion 616 which is configured to create a variable
reluctance air gap 618 with elongate rotor member 604. The end of stator pole
piece 588 includes an arcuate portion 620 which is likewise configured to create
a variable reluctance air gap 622 with rotor member 604. In particular, portion
618 includes a circumferential curvature which has a center point offset below
the axis of rotation of shaft 602 and rotor member 604 as indicated by circle
624 shown in shadow. Similarly, portion 620 includes a circumferential radius of
curvature which has a center point offset above the axis of rotation of shaft
602 and rotor member 604. When magnetic flux is passing along the path which
includes a given end of the assembly, maximum coupling between the rotor member
and stator pole pieces occurs when the rotor is positioned as shown in FIG. 25B.
Accordingly, the illustrated rotor member and stator pole piece configurations
in and of themselves do not provide any skewing to the direction of rotation of
the rotor assembly.
In this regard, various configurations for the rotor
and ends of the stator pole pieces are shown in the end views of FIGS. 26-28,
which configurations provide skewing the direction of rotation. In particular,
in device 620 of FIG. 26 a rotor member 622 having notches 624 and 626, which
notches provide for greater magnetic coupling with the stator pole pieces 628
and 630 at corners 632 and 634 such that rotation is skewed in the clockwise
direction. If notches were instead located at corners 632 and 634, skewed
rotation in the counterclockwise direction would be the result. In device 620
such counterclockwise rotation could also be achieved by removing rotor 622 from
shaft 636, flipping it end to end, and replacing it on shaft 636.
In the
device 640 of FIG. 27, a portion 642 of the arcuate end portion of stator pole
piece 644 is removed and a portion 646 of the arcuate end portion of stator pole
piece 648 is removed. This configuration results in greater magnetic coupling
between rotor member 650 and stator pole piece 644 at corner 652, and greater
magnetic coupling between rotor member 650 and stator pole piece 648 at corner
654, such that rotation is skewed in the counterclockwise direction. Clockwise
rotation could be achieved by instead modifying the opposite side of stator pole
pieces 644 and 648.
FIG. 28 depicts an end view of a device 660 in which
the axis 662 of the arcuate end portion of upper stator pole piece 664 and lower
stator pole piece 666 is placed at an angle A as shown. This configuration
creates an unequal variable reluctance air gap where opposite corners of rotor
member 668 are closer to stator pole pieces 664 and 666. Further, the angle at
which maximum magnetic coupling between rotor member 668 and stator pole pieces
664 and 666 occurs is retarded by angle A. Rotation would be in the
counterclockwise direction for the illustrated configuration.
Referring
again to motor 580 of FIGS. 23-25, rotary motion of such device is depicted in
the end views of FIG. 29A-29D. In each end view the end cap has been removed to
show rotation of the rotor members and in each of FIGS. 29A-29D an end view
depicting rotor member 604 and an end view depicting rotor member 606 are shown
side-by-side. In FIG. 29A, rotor member 604 is defined as being at zero degrees
and rotor member 606 is defined as being at ninety degrees. Control coils 594,
598 are energized in a permanent magnet magnetic flux aiding manner such that no
magnetic flux passes through stator pole piece path portions 590B and 592B. This
allows rotor member 606 to move out of its ninety degree position and the
magnetic coupling between rotor member 604 and stator pole piece path portions
590A and 592A will cause rotation to the position shown in FIG. 29B and then
FIG. 29C. When rotor member 604 reaches the ninety degree position shown in FIG.
29D control coils 594, 598 are de-energized and control coils 596, 600 are
energized in a permanent magnet magnetic flux aiding manner causing rotation to
continue due to the magnetic coupling between rotor member 606 and stator pole
piece path portions 590B and 592B. Thus, by alternatingly energizing the control
coils of each path with every ninety degree rotation of rotor members 604 and
606, continuous rotary motion is achieved.
The initial direction of
rotation can be controlled by the circuit means used to energize control coils
594, 598 and 596, 600, which circuit means includes circuitry for detecting the
angular position of the rotor members. In particular, if rotor members 604 and
606 are at rest in the position shown in FIG. 29A, and coils 594, 598 are
energized in an aiding manner, rotation may be clockwise or counterclockwise. If
the desired direction is clockwise but upon energization of coils 594, 598 the
rotor members begin to move counterclockwise, the detection circuitry will
immediately de-energize coils 594, 598 and energize coils 596, 600 so that the
counterclockwise direction is achieved.
Further, bypasses around
permanent magnets 582 and 584 could be provided in rotary motion device 580,
such as those shown in FIG. 12, and rotor members 604 and 606 could be formed by
permanent magnets so as to take advantage of energizing the control coils in an
exceeding manner.
A third embodiment of a rotary motion device or motor
650 is shown in the exploded partial perspective view of FIG. 30 and in the
assembled partial perspective view of FIG. 31. In motor 650 the stator assembly
includes a control component 651 including a permanent magnet 652 having a
stator pole piece 654 positioned adjacent one pole face thereof and a stator
pole piece 656 positioned adjacent the opposite pole face thereof. Stator pole
piece 654 includes a path portion 658A extending to one side of permanent magnet
652 and a path portion 658B extending to the one side thereof and spaced from
first path portion 658A. Control coils 660 and 662 are positioned along
respective stator pole piece path portions 658A and 658B. Likewise, stator pole
piece 656 includes path portions 664A and 664B which extend in a similar manner
therefrom so as to be aligned with stator path portions 658A and 658B
respectively. Control coils 666 and 668 are positioned along respective stator
pole piece path portions 664A and 664B. Positioned opposite and facing control
component 651 is a like control component 670 including permanent magnet 672,
stator pole piece 674 with path portions 676A and 676B having respective control
coils 678 and 680, and stator pole piece 682 with path portions 684A and 684B
having respective control coils 686 and 688. The end of each of the pole piece
path portions 658A, 658B, 664A, 664B, 676A, 676B, 684A, and 684B is of a
generally arcuate configuration.
A rotor assembly of motor 650 includes
a non-magnetic shaft 700 having a permanent magnet rotor member 702 mounted
thereon for rotation therewith. Permanent magnet rotor member 702 is generally
ring-shaped and segmented to include distinct north and south pole faces which
reverse about every ninety degrees therearound. When assembled the top and
bottom surfaces of permanent magnet rotor member 702 align with pole pieces 654,
656, 674, and 682 of the stator assembly and are preferably configured such that
a minimal gap between the outer surface of permanent magnet rotor member 702 and
the arcuate surfaces of the pole piece path portions is provided.
Rotation of device 650 can be achieved by controlled, timed energizing
and de-energizing of control coils 660, 662, 666, 668, 678, 680, 686, and 688.
Exemplary rotation is demonstrated with reference to the top views of FIGS.
32A-32B which depict counterclockwise rotation of permanent magnet rotor member
702 through one-hundred eighty degrees. In FIG. 32A stator pole piece path
portion 658A of component 651 is active and stator pole piece path portion 658B
is not active, which may be achieved by energizing control coil 660 in a
permanent magnet magnetic flux aiding manner or by energizing control coil 662
in a permanent magnet magnetic flux opposing manner. Stator pole piece path
portion 676B of component 670 is active and stator pole piece path portion 676A
is not active, which may be achieved by energizing control coil 680 in a
permanent magnet magnetic flux aiding manner or by energizing control coil 678
in a permanent magnet magnetic flux opposing manner. Thus, portions 690 and 692
of permanent magnet rotor member 702, which both have a north magnetic polarity,
will be repelled by the north polarity of stator pole piece path portions 658A
and 676B aligned therewith. Portions 694 and 696 of permanent magnet rotor
member 702, both of which have a south magnetic polarity, will be attracted to
the active path portions 658A and 676B. At the instant that rotor member portion
694 becomes aligned with stator pole piece path portion 658A, as shown in FIG.
32B, all coils are de-energized such that all pole piece path portions will be
active as shown. Pole piece path portions 658B and 676A are then kept active
while pole piece path portions 658A and 676B are made inactive. This is achieved
by energizing control coils 662 and 678 in a permanent magnet magnetic flux
aiding manner or by energizing control coils 660 and 680 in a permanent magnet
magnetic flux opposing manner. Rotor member portions 690 and 692 will again be
repelled by the north polarity of path portions 658B and 676A aligned therewith
such that rotation of permanent magnet rotor 702 is continued. In FIG. 32D all
coils are shown de-energized when rotor portion 692 aligns with pole piece path
portion 658A. By continuing this timed sequence of energization and
de-energization of the control coils, continued rotary movement is achieved. As
explained above, the initial direction of rotation can be controlled by circuit
means which detects the initial direction of permanent magnet rotor 702 and
immediately alters the coil energization scheme if the initial direction is
incorrect.
A side view of assembled motor 650 is shown in FIG. 33 and
includes an upper housing or enclosure portion 710, a bottom housing portion
712, upper bearing 714, and a lower bearing 716.
A fourth embodiment of
a rotary motion device or motor 740 is illustrated in FIGS. 34-39. Motor 740
includes five stator control components 742A-742E positioned around a ring
shaped permanent magnet rotor member 744 (FIG. 36). As shown with reference to
component 742A in FIG. 37 each stator component 742A includes a permanent magnet
746A with an upper pole piece 748A positioned adjacent one pole face thereof and
a lower pole piece 750A positioned adjacent the opposite pole face thereof.
Control coils 752A, 754A are positioned along respective pole pieces 748A, 750A.
A bypass 756A extends from pole piece 748A to pole piece 750A and is positioned
between permanent magnet 746A and control coils 752A, 754A. Alternatively,
bypass 756A could be provided on the opposite side of permanent magnet 746A as
shown in FIG. 38. Although not shown, it is anticipated that permanent magnet
rotor member 744 would be mounted on an axis for rotation therewith and that a
motor housing or enclosure could be provided, such as shown in relation to motor
650 of FIG. 33.
Referring to the top views of FIGS. 39A-39D, rotary
motion of rotor member 744 is depicted by the sequence of views. Regions 770 and
772 in FIGS. 39A-39D represent the magnetic north regions of the top of
permanent magnet rotor 744. In FIG. 39A control coils 752E and 752C are
energized in a permanent magnet aiding and exceeding manner such that regions
770 and 772 of permanent magnet rotor 744 are repulsed by components 742E and
742C while permanent magnet motor regions 774 and 776 are attracted by
components 742E and 742C. The resultant coupling forces act to move permanent
magnet rotor in a counterclockwise direction to the location shown in FIG. 39B.
Just after permanent magnet rotor region 772 passes the point shown in FIG. 39C,
control coil 752B is energized in a permanent magnet aiding and exceeding
manner, while control coils 752E and 752C also remain energized, and
counterclockwise rotation of permanent magnet rotor 744 is continued. Just after
permanent magnet rotor region 772 passes by control component 742C control coil
752C is de-energized, while control coils 752E and 752B remain energized, so as
to continue counterclockwise rotation. Then, just after permanent magnet rotor
region 770 reaches the location shown in FIG. 39D control coil 752D is energized
in a permanent magnet flux aiding and exceeding manner, while coils 752E and
752B remain energized, so as to continue counterclockwise rotation. Thus, as in
the other embodiments, repeated and timed energization and de-energization of
the control coils produces the desired rotational movement.
In terms of
controlling the energization of coils in the devices described above, various
electronic control circuit/switching means and electromechanical control
circuit/switching machines are depicted in FIGS. 40-44. In circuit 800 of FIG.
40 a given coil 802 is placed in series between an electrical energy source 804
and a power mosfet 806. An LED 808 is connected to electrical energy source 804
through resistor 810 and is positioned to impinge upon a phototransistor 812
which is connected in series with resistor 814. A control input of mosfet 806 is
connected between phototransistor 812 and resistor. Accordingly, when LED 808
activates phototransistor 812 the voltage drop across resistor 814 activates, or
turns ON, mosfet 806 and coil 802 is energized. Timed energization of coil 802
is provided by mounting an interrupter 816, such as shown in FIG. 42, to the
shaft 816 of the motor device to be controlled, such that as interrupter 814
rotates with shaft 816 coil 802 is alternately energized and de-energized. In a
device with a plurality of coils a corresponding plurality of LED/photoresistor
pairs may be provided.
In circuit 820 of FIG. 41 a coil 822 is
positioned between electrical energy source 824 and power mosfet 826. A hall
switch 828 is connected in series with resistor 830. Hall switch 828 is also
connected to the control input of mosfet 826 through resistor 832. In a given
device hall switch 828 would be positioned to react to a change in magnetic flux
so as to control the ON/OFF switching of mosfet 826, and thus the alternate
energization and de-energization of coil 822.
In FIG. 43 a circuit 840
for controlling two coils in an opposite manner is provided such that when coil
842 is energized coil 844 is de-energized, and such that when coil 842 is
de-energized coil 844 is energized. Both coils 842 and 844 are connected in
series between electrical energy source 846 and respective power mosfets 848 and
850. An LED 852 and phototransistor 854 arrangement is provided, LED connected
in series with resistor 856 and phototransistor connected in series with
resistor 858. When LED 852 turns phototransistor 854 ON the voltage drop across
resistor 858 turns mosfet 848 ON and coil 842 is energized. At that time the
voltage applied at the control input of mosfet 850 will be low and therefore
mosfet 850 will be OFF and coil 844 will be de-energized. When interrupter 814
blocks LED 852, phototransistor 854 is turned OFF and mosfet 848 is likewise
turned OFF. The control input of mosfet 850 is therefore pulled high through
resistor 860 and mosfet 850 is turned ON such that coil 844 is energized.
In a FIG. 44 a system 870 including member 872 mounted on rotating shaft
874 is provided, with the left side of member 872 being alternately conductive
at 876 and non-conductive at 878. Coils 880 and 882 are connected to respective
brushes 884 and 886 which are positioned to contact member 872 during rotation
thereof. Member 872 is connected through brush 890 to power supply 888. Thus,
coils 880 and 882 will alternatingly be energized and de-energized as the
respective brushes thereof contact the conductive and non-conductive portions of
member 872.
Any of such circuit means, variations thereof, or other
circuit means may be used to provide the timed energization of the control coils
in the various embodiments of the present invention.
From the preceding
description of the illustrated embodiments, it is evident that the objects of
the invention are attained. Although the invention has been described and
illustrated in detail, it is to be clearly understood that the same is intended
by way of illustration and example only and is not to be taken by way of
limitation.
For example, although the magnetic flux control techniques
of the present invention have been discussed as applicable mainly to various
motive applications, such magnetic flux control techniques are also useful in
static applications.
Power Conversion
Referring to FIGS. 45A-45C
there is shown the permanent magnet device 900 of FIGS. 45A-45C that has two
magnetic flux paths provided by rectangular pole piece 902 which includes upper
portion 904 and lower portion 906 each positioned against a respective pole face
of permanent magnet 910. Unlike the device of FIGS. 7-9, fall away armatures are
not provided. Rather, fixed armatures in the form of integral pole piece
portions 912 and 914 extend from upper portion 904 to lower portion 906
completing the two flux paths in a permanent manner. Control coils 916, 918 are
provided along one flux path and control coils 920, 922 are provided along the
other flux path, such control coils acting as primary windings in device 900.
One coil 924 is positioned around pole piece portion 912 and another coil 926 is
positioned around pole piece portion 914, such coils 924, 926 acting as
secondary windings in device 900.
In FIG. 45A coils 916, 918 are
energized in a permanent magnet magnetic flux aiding manner so as to couple with
all the magnetic flux of permanent magnet 910. All magnetic flux flows along
path 930 as shown and thus couples with coil 924. In FIG. 45B no coils are
energized and the permanent magnet magnetic flux splits evenly between paths 930
and 932, coupling with both coil 924 and coil 926. In FIG. 45C coils 920, 922
are energized in a permanent magnet magnetic flux aiding manner such that all
magnetic flux traverses path 932 and couples with coil 926. In FIG. 45D no coils
are energized as in FIG. 45B. By continuously alternatingly energizing and
de-energizing coils 916, 918 and 920, 922 in such a manner energy conversion is
achieved due to the coupling with coils 924 and 926. The magnetic flux in the
integral pole piece portions 912 and 914, and thus the flux coupling with
respective coils 924 and 926, varies by a factor of twice the amount of magnetic
flux generated by energizing coils 916, 918 and 920, 922.
The
construction shown in FIGS. 45A and 45X are similar to the construction shown in
FIGS. 7 and 47. The difference in both cases relates to replacing the two flux
paths and armatures with one continues flux path. The arrangement in FIG. 7 has
one permanent magnet and four coils and the arrangement in FIG. 47 has two
permanent magnets and two coils. Although the physical aspects of the two
arrangements and the details of the flux control vary, the control method for
varying the permanent magnets flux are similar and will be described
simultaneously and only differences will be pointed out.
With continuous
flux paths the static flux from the permanent magnet or magnets is useless.
However, if the static flux of the permanent magnet confined to the flux paths
were modified to be time varying it would have utility for electromagnetic
induction devices for power conversion like transformers and power inverters.
However, the same basic method for controlling the flux of a permanent magnet to
provide linear and rotary motion can also be applied to time varying the static
flux from the permanent magnetic. The construction shown in FIG. 45X utilizes
four control coils and a single permanent magnet and the construction shown in
FIG. 45A uses two control coils and two permanent magnets. The flux that would
normally be supplied by a primary winding is supplied by the static flux of the
permanent magnet or magnets and the control coils convert this static flux into
a time varying flux in a novel way. Both arrangements use two secondary coils,
the secondary coils are placed in the region of the continuous flux path that
would be occupied by an armature or rotor in the linear or rotary arrangements.
The regions of the flux paths that perform work are the same in all cases.
In all cases the control coils can either be wired in series or parallel
and the secondary coils can be either wound in series or parallel. More than one
secondary coil or secondary coils with multiple taps can be placed in the
working regions and further multiple flux paths can be utilized with one or more
secondary coils placed in each of the working regions. This is made obvious by
the disclosures of the linear and rotary devices herein and based on the fact
that the working regions of the flux paths are identical.
FIGS. 45X and
45A also show the paths of the static flux of the permanent magnet or magnets
when no current is flowing in the control coils. In the arrangement shown in
FIG. 45X the flux from the single permanent magnet divides between the two
working areas of the flux path. In the arrangement of FIG. 45A all of the flux
of one of the permanent magnets passes through one of the working regions and
all of the flux of the second permanent magnet passes through the other working
region. Each of the working regions in both cases are occupied by secondary
coils.
FIGS. 45Y and 45B show the control coils energized with the
polarity shown with respect to the polarity of the permanent magnet or magnets
included. In FIG. 45Y the opposing coil blocks the passage of flux from the
permanent magnet and the aiding coil couples with the flux of the permanent
magnet and therefore all of the flux of the permanent magnet passes through one
working region as shown. In FIG. 45A the opposing side of the coil blocks the
passage of flux from the permanent magnet on the opposing side of the coil and
the aiding side of the coil couples with the flux of the other permanent magnet
and therefore all of the flux of both the permanent magnets passes through the
working region as shown.
FIGS. 45Z and 45C show the control coils
energized with a polarity opposite of that shown in FIGS. 45Y and 45B. The same
action occurs and results in all of the permanent magnet or magnets path flux
passing through the opposite working regions.
By alternating the
polarity of the control coils during one cycle, one working region experiences
an increasing flux and the opposite region experiences a decreasing flux and
during the next cycle the opposite occurs. This results in the induction of a
voltage in the secondary coils that is decided by the magnitude of the change in
flux in the working region and the time in which this change occurs. The novelty
of this discovery is that the primary flux inducing the voltage in the secondary
coils is supplied by the permanent magnet or magnets and is far greater than the
flux supplied by the control coils.
Further, in the rotary motion
devices of FIGS. 31 and 34, it is not necessary that respective rotor members
702 and 744 be formed of permanent magnets. Each could take the form shown in
FIG. 46 where sections 950 and 952 are formed of magnetic material such as soft
iron and sections 954 and 956 are formed by a non-magnetic filler material.
FIGS. 47 and 48 show another embodiment 1000 of the subject device. The
embodiment 1000 includes two spaced permanent magnets 1002 and 1004 each of
which has its north pole adjacent the upper surface and its south pole adjacent
the lower surface. A magnetizable bridging member 1006 extends across and makes
contact with the north magnetic poles of the magnets 1002 and 1004 and another
magnetizable bridging member 1008 makes contact with the south magnetic poles of
the two permanent magnets 1002 and 1004. The members 1006 and 1008 extend
slightly beyond the opposite sides of the respective permanent magnets 1002 and
1004 and a pair of spaced armature members 1010 and 1012 are positioned to move
into and out of engagement with the ends of the members 1006 and 1008. Coils
1014 and 1016 are mounted respectively on the members 1006 and 1008 in the space
between the permanent magnets 1002 and 1004, and the armatures 1010 and 1012 are
shown connected together by a rod 1018 which enables them to move backwards and
forwards into engagement with the respective members 1006 and 1008 when
different voltages are applied to the respective coils 1014 and 1016. In FIGS.
47, the coils 1014 and 1016 are energized as shown with the coil 1014 having its
north magnetic end to the left and its south magnetic end to the right and the
opposite is true of the coil 1016. In FIG. 48, the voltage applied to the
respective coils 1014 and 1016 is reversed so that the polarity of the left end
of coil 1014 is south and the polarity of the opposite end of the same coil 1014
is a north magnetic pole. The reverse is true of the coil 1016. It is to be
noted in FIGS. 47 and 48 that the relationship of aiding and opposing is
indicated on the figures to indicate the relationship when the coils are
energized. For example, in FIG. 47 when the coils are energized as shown the
relationship is opposing for the permanent magnet 1002 and is aiding with
respect to the permanent magnet 1004. The reverse is true when the voltage on
the coils is reversed as shown in FIG. 48. By properly timing the voltage on the
respective coils the movement of the armature is controlled. The same principles
can be applied to produce rotating movement as shown in FIG. 42.
FIG. 49
shows another embodiment 1030 of the subject invention using principles similar
to those described in connection with FIGS. 47 and 48. The embodiment 1030
includes a plurality, three being shown, of stationary members 1032, 1034 and
1036. The details of these members are better shown in FIG. 50 which shows the
details of the member 1036. This member includes a pair of permanent magnets
1038 and 1040, each of which has magnetizable members mounted adjacent opposite
sides thereof as in the previous construction. The members 1042 and 1044 also
have coils 1046 and 1048, respectively, and the coils are energized as described
in connection with FIGS. 47 and 48 to produce aiding and opposing magnetism. The
construction shown in FIG. 49 may have three stator portions as shown or it may
have more stator portions as desired. The rotor 1050 is positioned in the space
between the members 1032, 1034 and 1036 and includes a permanent magnet portion
part of which has its north magnetic pole on the surface as shown and the other
parts has its south magnetic pole in the same surface as shown. The permanent
magnets 1038 and 1040 on the stators interact with the permanent magnets on the
rotor to produce the rotating motion and is controlled by the energizing of the
coils.
Other applications and advantages of the devices and methods of
the present invention exist and various modifications are possible, and
therefore the present invention is not intended to be limited to the specific
examples disclosed herein. Accordingly, the spirit and scope of the invention
are to be limited only by the terms of the appended claims.
Joe Flynns Parallel Path Magnetic Technology by Tim Harwood
Charles Flynn's own website with more on his device"