BACKGROUND OF THE INVENTION Rotating electric machines such as DC motors have been used for providing kinetic energy for various applications such as machines, vehicles and household appliances, etc. Attempts have been made to improve the efficiencies of the motor. Devices combining motor and power generators have also been developed to utilize the generated power for various purposes.

US Patent 5,258, 697 discloses a permanent magnet electric motor that includes a rotor with a plurality of permanent magnets; a stator with a plurality of electromagnets and a controller coupled to the electromagnets to energize them. In operation, one set of electromagnets is energized primarily to negate their backward attraction to the respective set of permanent magnets that are moving away from the electromagnets. Torque is obtained by the magnetic attraction of the other set of permanent magnets toward the core of the other set of the electromagnets.

Since electromagnets are powered to negate the backward attraction force, these types of motors have a lower efficiency and higher power consumption.

US Patent 5,574, 340 discloses a combined electromagnetically powered first motor and an electrically powered second motor both being powered by a primary power source. The first motor has at least one stationary electromagnet for driving, when energized, at least one permanent magnet on the rotor and for producing, when de-energized, a secondary electrical energy. The second motor is electrically coupled to the first motor for receiving the secondary electrical energy from the electromagnets to enhance rotational speed and torque output power.

US Patent 5,514, 923 discloses a DC motor with generator and flywheel characteristics.

The motor comprises a rotor having a plurality of permanent magnets, a stator having a plurality of windings energized by a rechargeable power pack. The motor is operable simultaneously in a motor-mode, a generator mode and a flywheel-mode. When energized, the windings repel the respective permanent magnets to cause the rotor to rotate (motor-mode). When de-energized, the

windings generate electric power when the respective permanent magnets pass over. Such electric power can be stored and charged back to the rechargeable power pack, through a control system comprising a generated current sensor, a current consumption sensor, a rotor position sensor and a microprocessor.

In the above patents 5,574, 340 and 5,514, 923, individual permanent magnets are mounted separately on the rotor disc, therefore the areas between the magnets on the rotor disc are left without full magnetic coverage. The interactive force between the electromagnets and the permanent magnets, which rotates the rotor, is therefore limited due to the structural constraint of the permanent magnet arrangement. Since the interactive forces between the electromagnets and the individual permanent magnets are substantially the same, attractive or repulsive forces generated contrary to the direction of rotation must be avoided by using a complicated control system.

Additionally, because the same group of windings are alternately used as a magnetic force generating means and an electric power generating means, the control system for both energizing de-energizing the windings and collecting generated electric power may become overly complex, resulting in reduced reliability.

SUMMARY OF THE INVENTION According to one embodiment of the present invention, a rotating electric machine is provided. The machine comprises a stator, a rotor and preferably a vacuum chamber for housing the rotor such that the rotor is rotatable in the vacuum chamber. The stator includes a first group of windings, and the rotor includes a first corresponding permanent magnet associated with the at least one group of winding.

A rotating electric machine according to the present invention may be configured to work as an electric motor or an electric power generator, or both. When worked as an electric motor, the first group of windings is energizable to become electromagnet (s) and interact with the corresponding permanent magnet. The rotor is therefore rotatable by these interactive actions.

When worked as an electric power generator, the rotor rotates so that the interaction between the permanent magnet and the windings generates electricity. In either mode, the rotor is rotatable in the vacuum chamber therefore the magnetic interactions between the winding and the permanent magnet can be improved.

Accordingly in a first aspect the present invention may broadly be the to further comprise a power source for selectively energizing the first group of windings. The rotor has an axis of rotation and a first permanent magnet is a permanent magnet disc including a first end surface adjacent to and facing the first group of windings; the axis of rotation passing perpendicularly through the center of the permanent magnet disc, the first end surface including a magnetic N-pole and an oppositely S-pole region spaced diametrically apart from each other across the axis of rotation, such that the N-pole region and the S-pole region pass sequentially over the windings with rotation of the rotor about the axis of rotation, wherein for each the N-pole region and S-pole region, at least one of the radial width of the region and the degree of magnetism of the region vary along the circumferential length of the region, the magnetic field of each N-pole or S-pole peaking closer to one end than the other.

Preferably, the radial width is greater toward one end than the other.

Alternatively, the degree of magnetism is higher toward one end than the other.

Preferably, the N-pole and the S-pole regions are substantially the same shape.

Preferably, the N-pole and the S-pole regions cover the full area of the first end surface of the permanent magnet disc and more preferably, the N-pole and the S-pole regions each covers substantially half of the full area of the first end surface of the permanent magnet disc.

Preferably, the first group of windings further comprises a first pair of windings, connected in series so as to be opposite polarity when energized, and the rotating electric machine further comprises a first circuit connecting the first pair of windings to the power source through a controller.

Preferably, the stator includes a second group of windings and the rotor further comprises a second permanent magnet associated with the second group of windings for generating electric power.

Preferably, the stator further comprises of a plurality of groups of electrically energizable windings and the rotor further comprises a plurality of permanent magnet discs associated with the corresponding windings for affecting the rotational motion of the rotating electric machine.

According to a second aspect of the present invention, there is disclosed a rotating electric machine comprising a stator having a group of coils; a rotor having at least one permanent magnet associated with the group of coils for generating electric power when the rotor is rotating.

Preferably, the group of coils is placed inside the vacuum chamber. Alternatively, the group of coils may be placed outside the vacuum chamber.

This invention may also be the broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of the parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

A rotating electric machine according to the present invention may generate effective power output with reduced power consumption and simplified yet reliable controlling system for providing an improved power source for use in various applications.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partial side elevation in cross section of the rotating electric machine according to a first embodiment of the present invention, Fig. 2 is a perspective view of the first permanent magnetic disc of Fig. 1 showing the different magnetic zones according to the present invention, Fig. 3 is a perspective view of the first permanent magnetic disc of Fig. 1 showing the magnetic field strength distribution according to the present invention, Fig. 4 is a block diagram showing the control circuit according to a first embodiment of the present invention, Figs. 5A-5F shows relative positions between the first permanent magnet disc and the first group of windings and the corresponding positions of the distribution disc in different moments of a rotation cycle according to the first embodiment of the present invention, Fig. 6 shows a block diagram of an alternative configuration of the control circuit according to Fig. 3, Figs. 7A-7F shows various alternative configurations of the permanent magnet disc pattern and the first group of windings according to the present invention, Fig. 8 is a partial side elevation in cross section of the rotating electric machine with a generator assembly according to a first embodiment of the present invention as shown in Fig. 1,

Fig. 9 is a partial side elevation in cross section of the rotating electric machine according to a second embodiment of the present invention, Fig. 10 is a partially cross-sectional bottom view of Fig. 8 showing a first alternative configuration of the electric generation winding, Fig. 11 is a partially cross-sectional bottom view of Fig. 8 showing a second alternative configuration of the electric generation winding, Fig. 12 a partially cross-sectional top view of the distribution disc showing the positions have the first and the second actuators when the distribution disc is stationary, Fig. 13 is a partially cross-sectional top view of the distribution disc showing the early activation of the switch by the first actuator when the distribution disc is rotating, and Fig. 14 is a partially cross-sectional top view of the distribution disc showing the early deactivation of the switch by the second actuator when the distributor disc is rotating.

Fig. 15 is a partial side elevation in cross section of the rotating electric machine with a generator assembly according to a further embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotating electric machine according to the present invention may be configured to work as an electric motor or an electric power generator, or both. When worked as an electric motor, a first group of windings is energizable to become electromagnet (s) and interact with a corresponding permanent magnet. The permanent magnet, which is coupled to a rotor, is therefore rotatable by this interactive action. The present invention may be used both as a motor and an electric power generator. When used as a generator, the rotor rotates so that the interaction between the permanent magnet and the windings generates electricity. In either mode, the rotor is rotatable in the vacuum chamber therefore the magnetic interactions between the winding and the permanent magnet can be improved.

Fig. 1 shows a rotating electric machine according to a first embodiment of the present invention. The rotating electric machine comprises primarily a stator, a power source and a rotor.

The rotor comprises a shaft 10, a first permanent magnet which is a disc 20 mounted on the shaft 10 through a support disc 30. The support disc 30 is made of non-magnetic material, such as copper. The rotor shaft 10 is supported by bearings 12 and 14. The bearings 12 and 14 may be any appropriate type of bearing such as normal ball bearings, magnetic bearings, hydrodynamic bearings or aerodynamic bearings. At one end of the shaft 10 there is mounted a

distribution disc or commutator 50. Carried by the rotor, the first permanent magnet disc 20 is rotatable along a first circumferential direction 200 about its axis of rotation 16 (Fig. 2).

The stator comprises of a housing 90, a housing cover 100, a first group of windings with six windings 110A, 1 IOB, 120A, 120B, 130A and 130B (only two windings 110A and HOB are shown) and a disc reader 60. The distribution disc 50 and the disc reader 60 forms a position controller, the function and construction of which shall be described in detailed later. The first group of six windings 110A, 110B, 120A, 120B, 130A and 130B are positioned in the housing cover 100 and adjacent to the permanent magnet disc 20, leaving a gap 102 therebetween. The first group of six windings 110A, 110B, 120A, 120B, 130A and 130B are selectively energizable by a power source 80. When energized, the windings 110A, 110B, 120A, 120B, 130A and 130B serve as electromagnets.

The first permanent magnet disc 20 comprises a first end face 22, which faces the first group of windings 110A, 1 IOB, 120A, 120B, 130A and 130B. The first end face 22 is comprised of an N-pole and an S-pole, as shown in Fig. 2. The N-pole and the S-pole are spaced diametrically apart from each other about the axis of rotation 16. Accordingly, the N-pole and the S-pole are rotatable with respect to the axis of rotation 16 along a first direction of rotation 200.

Referring to Fig 2, the N-pole and the S-pole are shaped with a circular head and an end that tapers along the circumference of the permanent magnetic disc 20 in the first direction of rotation 200. The N-pole and S-pole regions each consist of three zones 312,314, 316 and 322, 324, and 326 respectively and collectively referred to as the N-pole zone (or region) 401 and the S- pole zone (or region) 402. The line 400 shows the separation between the N-pole zone 401 and S- pole zone 402. In a preferred configuration, the N-pole and the S-pole are substantially the same size and shape and cover the full area of the first end face 22 of the permanent magnet disc 20.

The centers 322A and 312A of the two zones 322 and 312 are located at the mid points of the radius of the first end face 22. The first permanent magnet disc 20 is rotatable around axis 16 in the first direction of rotation 200.

Referring to Fig. 3, the direction of the magnetic field 403 is perpendicular to the first end face 22. The magnetic field strength of the N-pole zone 401 and S-pole zone 402 is proportional to their surface area and/or the degree of magnetism around a specific point. Therefore, the points of strongest magnetism are located at a point 312A located in zone 312 of the N-pole region 401 and at a point 322A located in zone 322 of S-pole region 402. The strength of the magnetic field 403 is weaker at the edges of the N-pole and S-pole zones 401 and 402 than at the point's 322A

and 312A. Therefore, moving along clockwise along the circumferential length 412 of the N-pole region 401 and the S-pole region 402, the strength of the magnetic field decreases as the radial width 422 (and therefore, surface area of the zone around a specific point) of the N-pole region 401 and S-pole region 402 decrease. Therefore, a first end 401A, 402A of each of the N-pole region 401 and S-pole region 402 possess a degree of magnetism stronger than a second end 401B, 402B. The regions 312,314, 316,322, 324, and 326 (refer to Fig 2) can be further illustrated by their respective magnetic strengths H312, H314, H316, H322, H324, and H326. The magnetic field strengths of all the zones are configured in the following fashion: H312 > H314 > H316 and H322 > H324 > H326.

Reference is now made to Fig. 4. The first group of six windings 110A, 110B, 120A, 120B, 130A and 130B are electrically connected in pairs 110A and HOB, 120A and 120B, 130A and 130B. The disc reader is comprised of three switches 310,320 and 330, which will be turned "OFF"when the distribution disc 50 passes therethrouth, and will be turned"ON"to the contrary.

The distributor disc 50 comprises a first trigger 52 for turning the switches 310,320 and 330 from an"OFF"state to an"ON"state, and a second trigger 54 for turning the switches 310,320 and 330 from an"ON"state into an"OFF"state. The first trigger 52 and the second trigger 54 are positioned 120-degrees apart. The distribution disc 50 is mounted on the same axis 16 with the first permanent magnet disc 20 and both follow the same direction of rotation 200. The switches 310,320, and 330 may be mechanically controlled, light sensing, or any other type of switch that is triggerable between an"OFF"and"ON"state by the distribution disk 50.

A first circuit 210 connects the power source 80, the first pair of windings 110A, HOB and the first switch 310 in series. Likewise, a second circuit 220 connects the power source 80, the second pair of windings 120A, 120B and the second switch 320 in series; a third circuit 230 connects the power source 80, the third pairs of windings 130A, 130B and the third sensor 330 in series.

The first pair of windings 110A, 110B are wound so when energized, the winding 110A becomes an electromagnet with its N-pole facing the primary N-zone 312 of the first permanent magnet disc 20 at the center point 312A, and winding 110B becomes an electromagnet with its S- pole facing the primary S-zone 322 of the first permanent magnet disc 20 at the center point 322A.

As the first pair of windings 110A, HOB are respectively aligned with the center points 312A, 322A of the N-pole and the S-pole at the time of start, repulsive forces between the winding 110A and the primary N-pole zone 312, and the winding HOB and the primary S-pole zone 322

will be in the direction substantially perpendicular to the first surface of the first permanent magnet disc 20 therefore it will not cause the permanent magnet disc 20 to rotate. The magnetic strength of both the N-pole zones 312,314, 316 and the S-pole zones 322,324, 326 are unevenly distributed, thus repulsive forces will be generated between the winding 110A and the secondary N-zones 314,316, and the winding 110B and secondary S-zones 324,326. These forces drive the permanent magnet disc 20 to rotate in the direction of rotation 200.

Immediately after the start of rotation of the permanent magnet disc 20, the first pair of windings 110A, 110B become un-aligned with respect to the primary N-zone 312 and the primary S-zone 322. Stronger repulsive forces will be generated between the winding 110A and the primary N-pole zone 312, and winding 110B and the primary S-pole zone 322, which will accelerate the rotation of the permanent magnet disc 20.

Reference is now made to Fig. 5. The first pair of windings 110A and HOB remains energized until the permanent magnet disc 20 rotates clockwise to the 120-degree position from the starting position, the 0-degree position. During this period, as shown in position 5B, one sample position between 0 and 120-degrees, rotation of the permanent magnet disc 20 is effected by the repulsive forces between the winding 110A and N-pole zone 401, winding 110B and S-pole zone 402, and the simultaneous attractive forces between the winding 110A and the S-pole zone 402, winding 110B and the N-pole zone 401. Although the permanent magnet disc 20 in this embodiment of the present invention rotates clockwise, one of skill in the art may reorient the magnet disc and corresponding windings to rotate anti-clockwise.

Upon reaching position 5C, the 120-degree position, the second trigger 54 turns off the first switch 310 whereby opening the first circuit 210 and simultaneously, the first trigger 52 turns on the second switch 320 to close the second circuit 220, refer to Fig. 4. The first pairs of windings 11 OA, 11 OB are de-energized and the second pair of windings 120A, 120B are energized.

Subsequently, magnetic interaction occurs between the second pair of windings 120A, 120B and the N-pole and S-pole zones 401 and 402 of the permanent magnet disc 20 as in the same manner as illustrated above, which drives and accelerates the permanent magnet disc 20 to rotate continuously.

When the permanent magnet disc 20 reaches position 5E, the 240-degree position, the second switch 320 is deactivated and opens the second circuit 220. The third switch 330 is activated and closes the third circuit 230. The magnetic forces generated between the third pair of windings 130A, 130B and the N-pole and the S-pole zones 401 and 402, cause the permanent

magnet disc 20 rotate continuously. A rotation cycle is completed once the permanent magnet disc 20 and the distribution disc 50 returns to the 0-degree position, refer to Fig. 5A. The permanent magnet disc 20 combined with other parts of the rotor have a certain mass, this results in an inertia momentum which assists the rotation of the permanent magnet disc 20. The above operation cycle is repeated so that the permanent magnet disc 20 rotates continuously.

Fig 6 shows a single-phase rotating electric machine. It is comprised of one pair of windings 110A, HOB, a power source 80, a first switch 310 and associated distribution disc 50.

The operation of this circuit is similar to that described in Fig. 4, only simpler. Specifically there is one circuit with one set of control mechanisms as opposed to three in Fig. 4.

Fig. 7A-7F shows alternate configurations of the N-pole and S-pole zones 401 and 402 of the permanent magnet disc 20 and the first group of windings 110A, 110B, 120A, 120B, 130A and 130B.

Fig. 7A shows a configuration having a different number and shape of the first group of windings 110A, 1 l OB, 120A, 120B, 130A and 130B. In particular the number of windings has increased from six to ten and their shape has been modified to resemble a polygon 405A-405J.

The N-pole and S-pole zones 401 and 402 on the permanent magnet disc 20 remain the same.

Fig. 7B shows the N-pole and S-pole zones 401 and 402 towards the outer edge of the permanent magnet disc 20. This leaves the center of the permanent magnet disc 20 with an unmagnetized region. The two zones 401 and 402 cover substantially less than the full area of the first end face 22 of the permanent magnet disc 20.

Fig. 7C shows the N-pole and S-pole zones 401 and 402 towards the center of rotation of the permanent magnet disc 20, leaving the absolute center and outer edges of the permanent magnet disc 20 in an unmagnetized state. The two zones 401 and 402 cover substantially less than the full area of the first end face 22 of the permanent magnet disc 20.

Fig. 7D shows the N-pole and S-pole zones 401 and 402 towards the outer edge of the permanent magnet disc 20 but with the tapering end of each zone 401 and 402 following the axis of rotation of the centers of the windings t 10A, 1 IOB, 120A, 120B, 130A and 130B. The two zones 401 and 402 cover substantially less than the full area of the first end face 22 of the permanent magnet disc 20.

Fig. 7E shows the N-pole and S-pole zones 401,402 as acute regions with the outer edge of the regions 401 and 402 following the edge of the permanent magnet disc 20. The two zones 401 and 402 cover substantially less than the full area of the first end face 22 of the permanent magnet disc 20. The degree of magnetism on regions 401 and 402 vary along the direction 200, and in a preferred example, the degree of magnetism is decreased from one end 401A to another end 401B, and from one end 402A to another end 402B, respectively. The degree of magnetism may be adjusted based on the strength of the magnet.

Fig. 7F shows two sets of N-pole and S-pole zones labelled 406A, 406B and 407A, 407B.

These zones 406A, 406B, 407A and 407B are substantially the same size and shape as those discussed in Fig 7E. The degree of magnetism distribute in the similar way as that under Fig. 7E.

Figs. 8 and 9 show an alternative configuration to Fig 1. Each configuration has the addition of a generator (description follows) whereby the electricity generated may be directed back to the power source 80 for recharging purposes or other purposes.

Fig. 8 shows a rotating electric machine with a second permanent magnet disc 70 mounted on the rotor and a second group of windings 170 mounted on the stator. Rotating with the rotor, the second permanent magnetic disc 70 and the second group of windings 170 work as a generator.

The electricity generated may be directed back to the power source for purposes such as recharging. The housing 90 and the housing cover 100 may be fixed together in an airtight manner to form an isolated chamber for containing the rotor assembly. The air in the isolated chamber may be exhausted so that a vacuum chamber 95 may be obtained. This minimizes the undesirable effect of air resistance on the rotor during rotation and improvement of magnetic interaction between the second permanent magnet disc 70 and the second group of windings 170.

In this configuration shown in Fig. 9, a single magnet disc 71 is used. The magnet disc 71 comprises an annular recess 72 for receiving the second group of windings 170. Magnetic interaction between the second permanent magnet disc 70 and the second group of windings 170 may be improved under this configuration.

Fig. 10 and 11 show alternative configurations for the second group of windings 170.

They may be in the form of a plurality of windings 170A-170F as shown in Fig. 10, or a single winding 174 as shown in Fig. 11. These windings 170 and 174 may be placed inside the vacuum chamber 95 or alternatively, outside the vacuum chamber 95 to enable external cooling.

In the configuration shown in Fig 10, the group of windings 170 is in the form of a plurality of windings 170A-170F.

Fig. 11 shows the winding 174 taking on a single torus-shaped configuration.

Fig. 12 shows an alternative configuration of the distribution disc 50, which further comprises a first actuator 152 and a second actuator 252. The first actuator 152 is mounted onto the distribution disc 50 through a first pivot 154 and is rotatable thereabout between a first normal position 156 and an advance-activating position 158 (shown as dashed contour line 159). The second actuator is mounted onto the distribution disc 50 through a second pivot 254 and is rotatable thereabout between a second normal position 256 and an advance-deactivating position 258 (shown as dashed contour line 259). The first and the second normal positions are 120-degree apart. To correspond to this configuration, the first trigger 52 is positioned at the advance- activating position 158. Under this configuration, the first and second triggers 52 and 54 are positioned more than 120-degree apart.

When the rotor is not rotating (Fig. 12), the first actuator 152 is biased against a first normal position stopper 151 by a first resilient member (not shown). The second actuator is biased against a second normal position stopper 251 by a second resilient member (not shown). When rotated with the distribution disc 50 (Fig. 13), a first centrifugal force 157 will cause the first actuator 152 to rotate towards its advance-activation position stopper 153. The result of which will cause early activation of the first switch 310. This configuration may be useful for power sources, which requires certain lead-time from start before reaching the maximum level of power output.

Likewise, when rotated with the distribution disc 50 (Fig. 14), a second centrifugal force 257 will cause the second actuator 252 to rotate towards its advance-deactivation position stopper 253. The result of which will cause early deactivation of the first switch 310. This configuration may be useful for energy-saving purposes, as when the rotor rotates under a certain level of speed, the inertial momentum will contribute to the rotation of the rotor.

It should be appreciated that the configurations and structures of the rotating electric machine above are for illustrative purposes only. Variations and modifications may be made under the same inventive concept without departing from the following claims. For example, the N-pole and the S-pole of the first permanent magnet disc may be in a unique shape along the direction of rotation 200 (Fig. 7E and Fig. 7F), but with an unevenly arranged magnetic field

strength distribution along the direction of rotation 200. The first group of windings may have more windings or in different shape, for example the windings 405A-405J shown in Fig. 7A.

Fig. 15 shows a further embodiment of a rotating electric machine 600 of the present invention. In this embodiment, a set of windings 670 are disposed adjacent to and below the permanent magnet disc so that the magnetic flux of the magnet disc 20 passes through the windings 670. While only two windings 670 are illustrated, additional windings 670 may be added to increase the output of the rotating electric machine. The power generated by the set of windings 670 may also be rerouted to recharge the power source.