GB2111760A

GB2111760A - Motor

Info

Publication number: GB2111760A
Application number: GB08137675A
Authority: GB
Inventors: Henry Victor Rosse
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-12-14
Filing date: 1981-12-14
Publication date: 1983-07-06
Also published as: GB2111760B

Abstract

An a c or d c motor has a stator 3 and a rotor 7 with poles 11,12 respectively. Each revolution of the rotor 7 includes a portion FG wherein there is a force of attraction between the poles 11,12, a portion JK wherein there is a force of repulsion, a portion KL of free inertial motion of the rotor and a portion LX of logarithmic retardation of the rotor. One of poles 11,12 consists of first, continuously energised coil and a second, intermittently energised coil (L1, L2 in Figure 7). The other pole may be a coil (L3 in Figure 7) or a permanent magnet. The coils are controlled by a circuit including a relay or a transistorised control system responsive to the relative angular position of the stator 3 and rotor 7. Modified versions of the motor have three rotor poles and one stator pole or three poles on both stator and rotor. <IMAGE>

Description

SPECIFICATION Motor This invention relates to a motor.

Accordingly, the invention provides a motor comprising a stator having associated first pole means and a rotor mounted for rotation with respect to the stator and having associated second pole means, wherein one of said first and second pole means is energisable during rotation of the rotor through a first predetermined angie, to provide a magnetically attractive force between said first and second pole means and, as a consequence, acceleration of the rotor through said first predetermined angle, and wherein said one pole means when de-energised, provides a magnetically repulsive force between said first and second pole means over a second predetermined angle of rotation of the rotor, the combination of the attractive and repulsive forces between said first and second pole means during rotation of the rotor through said first and second predetermined angles being sufficient to provide a torque on the rotor which prevents total inertial deceleration of the rotor over the remaining angular portion of one revolution thereof.

In order that the invention may be more fully understood, preferred embodiments in accordance therewith will now be described by way of example and with reference to the accompanying drawings in which: Figure 1 is a schematic sectional side view of a first embodiment of motor; Figure 2 is a schematic plan view of the motor shown in Figure 1; Figure 3 is a circuit associated with the motor shown in Figures 1 and 2; Figures 4 and 5are diagrams illustrating the operation of the motors shown in Figures 1 and 2 under universal and d c operative modes, respectively; Figure 6 is a schematic plan view of a second embodiment of motor; Figure 7 is a schematic sectional side view of the motor shown in Figure 6; Figure 8 is a plan view of a third embodiment of motor; Figure 9 is a plan view of a fourth embodiment of motor;; Figure 70 is a plan view of a rotor for use in the motors described with reference to Figures 1 to 9; and Figures 11 and 12 are circuit diagrams of respective d c and a c circuits of the motors shown in Figures 6 to 9.

A first embodiment of motor as illustrated in Figures 1 and 2 comprises a generaily square base plate 1 with apertures 2 at each corner four mounting the motor. The base plate 1 has secured thereto a stator 3 in the form of a rectangularly-sectioned bar.

A shaft 4 extending perpendicularly with respect to the plane of the base plate 1, is journalled through the common centre of the stator 3 and the plate 1 by respective bearings 5, 6. A rotor 7, in the form of an inverted cup-shaped member, co-axially surrounds the stator 3 and is fixed to the shaft 4 for rotation therewith by means of a locknut 8. The inner surface 7' of the cylindrical wall of the rotor 7 is spaced by a small distance only from the ends of the stator 3 which may be curved to approximate to the curvature of this inner surface 7'. The base plate 1 supports an outer housing 9 which protects the rotor 7. The shaft 4 extends beyond the underside of the plate 1 to provide a mechanical power output in the form of a pulley 10 or gearwheel secured to the projecting free end of the shaft.The weight of the rotor 7 is concentrated in its cylindrical wall and, for purposes of explanation, the stator 3 is regarded as having a single pole 11 at one end and the rotor 7 is regarded as having a pole 12 in its cylindrical wall of about the same arcuate extent as that of the stator pole 11.

The motor incorporates two coils L1 and L2 as shown in the circuit of Figure 3, which can be wound or otherwise secured to the stator 3, in which event, the rotor pole 12 is provided by permanent magnet means. Alternatively, coils can be fitted on the rotor 7, in which event, the stator pole 11 is provided by permanent magnet means. An a cord c voltage is applied across input terminals A B of the circuit of Figure 3, and terminals C D are connected to a relay unit (not shown) or transistorised control system (also not shown) which makes or breaks the connection between these terminals C D at precisely predetermined times during each rotation of the rotor 7 around the stator 3.It will be seen that coils L1 and L2 are of the same polarity, whilst the coil L1 is continuously energized and current pulses are fed to the coil L2 as a result of the predetermined making and breaking of the connections between the terminals C D co-ordinated with the rotor movements. By appropriate selection of the values of the other circuit components R1, R2, C1 and C2 the current pulses fed to the coil L2 are made relatively large.

Referring now to Figure 4, in which the rotor operates in its universal mode, and considering the rotor pole 12 to be at its zero position represented by the arc E F with the leading edge or datum X of this pole lying on the radius F, there is at that time an attraction between the stator and rotor poles 11, 12 and to the continuous current coil L1. From this zero position of the rotor 7 to the base line G, in which the rotor pole 12 is directly adjacent the stator pole 11, current is supplied also to the coil L2, so that the attraction between the two poles is considerably enhanced. This attraction between the two poles 11, 12 occurs along the arc F G and when the two poles are in alignment, the current pulse to the coil L2 is terminated by breaking the connection between the terminals C D in the circuit shown in Figure 3.The now much accelerated rotor 7 continues to rotate in an anti-clockwise direction as indicated by the arrow R, overcoming the static loop resistance along the arc G H. A zero interaction, either attractive or repulsive, between the poles 11, 12 occurs along the arc H J and continued energization of the coil L1 then creates a repulsion between the stator and rotor poles 11, 12 along the arc J K. This repulsion supports the rotation of the rotor 7 which is maintained under effective free inertial motion along the arc K L. Along the extent of the arc LX, the rotor 7 undergoes logarithmic deceleration until such time as it again experiences acceleration along the arc F G due to the energization of the coil L2, as described above.

Figure 5 demonstrates the d c operative mode of the motor shown in Figures 1 and 2. Starting from the zero position with the leading edge or datum X' of the rotor pole 12 lying on the radius F', energization of the coil L1 provides an effective attraction between the two poles 11, 12, thus causing anticlockwise rotation of the rotor 7 to the base line position G' in which alignment of the two poles occurs. Continued movement of the rotor 7 is sustained through a zero field state represented by the arc G' J' and subsequently by a current pulse applied to the coil L2 which effects repulsion between the two poles 11, 12 along the arc J' K' thereby advancing the rotor 7 in its movement around the stator 3.As in the case of the operation of the motor described above with reference to Figure 4, the rotor 7 undergoes effective free inertial motion along the arc K' L' and then logarithmic deceleration along the remaining portion of one complete revolution defined by the arc L' X'.

Referring now to Figures 6 and 7 of the drawings, a second embodiment of motor in accordance with the invention is similar in construction to the motor described above with reference to Figures 1 and 2, except that the permanent magnetic pole 12 of the rotor 7 is replaced by a coil L3 and that switching of the current in the coil L2 is controlled by a stationary make and break contact 62 secured to the base plate 1 and operated by an arcuate, electrically insulating rail 61 adjustably secured to the inner surface 7' of the cylindrical rotor wall.

In this embodiment of motor, dc or ac current is continuously flowing through the stator coil L1 and rotor coil L3, whilst the current through the stator coil L2 is pulsed by virtue of the actuation of the contact 62 by the rotor rail 61, this pulsed current flow in the coil L2 reducing the current flow in the other stator coil L1. The principal of operation is the same as that described above with respect to the first embodiment of motor shown in Figures 1 and 2, when operating in either the universal or dc mode in accordance with Figure 4 or 5.

Circuits for operating the second embodiment of motor in the dc or universal (ac) mode are illustrated in respective Figures 11 and 12, wherein the terminals Y Z effectively represent the same referenced terminals for the rotor coil L3, as shown in Figure 7.

Similarly, the two circuits shown in Figures 11 and 12 can each be used in conjunction with the third and fourth embodiments of motor in accordance with the invention, as illustrated in Figures 8 and 9 respectively.

The third embodiment of Figure 8 has three rotor coils L3, whilst the stator 3 has a single pair of coils L1, L2. Here, the attraction and subsequent repulsion between the rotor and stator poles, and hence the effective rotation of the rotor 7 in the anti-clockwise direction of the arrow R is enhanced three-fold for each revolution, because the rotor has three coils.

For the fourth embodiment of motor shown in Figure 9, such enhancement is nine-fold over the first and second embodiments of motor described above. This is because the stator comprises three pairs of coils L1, L2 and the rotor 7 also has three coils L3.

As in the case of the second embodiment of motor, as described above with reference to Figures 6 and 7, switching of the pulsed current through the stator coil (s) L2 can be effected by means of a contact arrangement similar or identical to the contacts 62 and associated operating rail 61 shown in Figure 6. Also, it will be appreciated that in either the dc or universal (ac) operative mode of the third or fourth embodiment of motor, as shown in Figure 8 or 9, a switching circuit similar to that described above with reference to Figure 11 or 12, can be used.

Turning now to Figure 10, a preferred form of rotor 17 is illustrated, wherein three arcuate gaps 18 are provided. These gaps 18 reduce the internal weight of the rotor 17, whereby the inertial free motion of the rotor is improved and heat ventilation is assisted.

This shape of rotor 17 also constitutes a preferred form of flywheel arrangement for the four embodiments of motor as described above.

It will be appreciated that the positions of the stator and rotor can be superposed, whereby the rotor is mounted for rotation within the stator. The poles can be encased or moulded into non-magnetic and electrically non-conducting alloys in which case, the encased coils can be detachably mounted upon the stator and/or rotor. Advantageously, the rotor is precision balanced for efficient operation.

Each pole can be made of a solid or laminated soft magnetic material of low remnance. Where a laminated stator pole is used, the magnetic material should preferably be very soft to allow fastorientation of the magnetic domains when the current through the coil L2 is switched on and off.

The rotor pole can be made of a similar material but this is not critical, because, in the embodiments described above, the current passing through the coil L3 is continuous and is not switched.

The coils can be fitted or wound on the rotor or on the stator and can be series or parallel wound. The motor of the invention can be controlled by vacuum relays or entirely by solid state devices.

Furthermore the universal operative mode of each of the four embodiments of motor described above can be performed with dc voltages, as well as ac voltages. In the ac operative mode of the motor, a step-down transformer can be used, for reasons of efficiency and safety.

It will be evident from the foregoing that the invention provides an electric motor of high efficiency and which can be embodied in a variety of ways depending on the intended application. Thus small motors of the disc type can be constructed for use in medical and domestic fields, and medium size motors of the same type can be made for industrial applications and for transport, that is, for powering electric cars. Very large models, with rotary frames, can be employed in preferably electrical power supply from such natural resources as winds and waves and from nuclear reactors.

Claims

CLAIMS (Filed 8/12/82)

1. A motor comprising a stator having associated first pole means and a rotor mounted for rotation with respect to the stator and having associated second pole means, wherein one of said first and second pole means is energisable in a first state during at least one first predetermined angular portion of a revolution of the rotor to provide a magnetically attractive force between said first and second pole means and, as a consequence, acceleration of the rotorthrough said first predetermined angular portion, and wherein said one pole means is energisable in a second state to provide a magnetically repulsive force between said first and second pole means during at least one second predetermined angular portion of a revolution of the rotor, the combination of the attractive and repulsive forces between said first and second pole means during rotation of the rotor through said first and second predetermined angular portions providing a torque on the rotor sufficient for continuous rotation of the motor.

2. A motor according to claim 1, in which the rotor undergoes free inertial motion during at least one angular portion of each revolution.

3. A motor according to claim 1 or 2, in which the first and second pole means are each effective over a single peripheral portion of the stator and rotor respectively, whereby each revolution of the rotor includes a single first predetermined portion and single second predetermined portion.

4. A motor according to claim 1 or 2, in which at least one of the first and second pole means is effective over a plurality of equally-spaced peripheral portions of the stator or rotor, whereby each revolution of the rotor includes a number of first and second predetermined portions each equal to the number of peripheral portions.

5. A motor according to claim 4, in which the first and second pole means are each effective over equal numbers of peripheral portions of the stator and rotor.

6. A motor according to any one of claims 3 to 5, in which one of the first and the second pole means comprises first and second coils for the or each respective peripheral portion, the motor including energisation means for energising the first coil(s) continuously and the second coil(s) intermittently, the intermittent energisation of the second coil(s) being controlled by means responsive to the relative angular position of the rotor and stator to produce the said attractive and repulsive forces during the said first and second predetermined angular portions.

7. A motor according to claim 6, in which the pole means of the other of the stator and the rotor comprises permanent magnet means effective over the or each said peripheral portion.

8. A motor according to claim 6, in which the pole means of the other of the stator and the rotor comprises a respective coil forthe or each said peripheral portion, the coil(s) being continuously energisable by the energisation means.

9. A motor according to any one of claims 6 to 8, in which the means responsive to the angular position of the rotor and stator includes contacts operated by the rotor.

10. A motor according to any preceding claim, in which the rotor is mounted for rotation with the stator.

11. A motor according to any one of claims 1 to 9, in which the rotor is mounted for rotation around the stator.

12. A motor according to claim 11, in which the rotor has a cylindrical wall surrounding the stator and a circular end wall mounting the rotor to rotate about its central axis.

13. A motor according to claim 12, in which the end wall of the rotor is mounted on a pillar formed integrally with a base plate portion of the stator.

14. A motor substantially as hereinbefore described with reference to any Figure of the drawings.