AU757966B2 - Improved electric motor - Google Patents

Description

The accepted electric motor (Figure (Figure either D.C. or A.C. uses the magnetic principle of like magnetic poles repel, and unlike magnetic poles attract.

This principle and the knowledge that by changing the direction of an electrical current through an energised coil, changes the magnetic poles of the metallic, ferrite, or phenolic core passing through the energised coil. This method is used to cause rotation, by the push and pull action of the rotor or stator, depending on the design requirements of the electric motor. All the current designs suffer from the same design fault, and only use one side of the energised core to produce rotation movement of the rotor or stator. While it is not inefficient to only use one side of a permanent magnet, it is very inefficient to only use one side of an energised core.

Only half the potential of the electric motor is used. The object of this invention is to use both sides of the energised core. This is achieved by using various configurations of Stators, Rotors, permanent magnets and energised windings, all with the same aim of using both sides of the energised coil.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows the standard electric motor, with the rotor made up of "T" shaped segments radiating from the centre of the rotors, with the top of the "T" forming the outer circumference of the rotor only one side of the energised coil is used to provide rotation of the rotor 20 Figure 2 shows the standard Radial electric motor, with the "rotor" being made up of shaped segments facing outwardly from the centre of the rotor, with only one side of the energised coil being used to provide rotation by the permanent magnets in the stator Figure 3 shows the plan view of a round dish "the rotor" with permanent 25 magnets fitted near its circumference. In this drawing the rotor rotates 25 magnets fitted near its circumference. In this drawing the rotor rotates around a fixed shaft A single shaped core (11) and energising coil are fitted at the top.

Figure 4 shows the side view of Figure 3, with a shaped core (11) fitted with an energising coil (10) fixed to the side of the stator in line with the arc formed by the permanent magnets and fitted with a dust cover (21).

Figure 5 shows the side view of the rotor fitted with a wheel and with two cores (11) fitted with energised coils (10) positioned either side of the top of the rotor Figure 6 shows the side view of the rotor in the shaft holder stand (14) with the energised coils (11) and coils (10) fitted to the stator and positioned both sides of the bottom of the rotor in line with the permanent magnets in the rotor Figure 7 shows a section of the plan view of the rotor with the shaped core (11) and the energising coil (10) positioned one side of the rotor and with all 15 the North magnetic poles facing the same side of the rotor The length between the ends of the core (11) is one and a half times the length between the permanent magnets fitted in the rotor Figure 8 shows a section of the plan view of the rotor with the shaped cores (11) and the energised coils (10) positioned both sides of the rotor with 20 alternative magnetic poles facing one side of the rotor the ends of the energised core (11) line up with the permanent magnets in the rotor Figure 9 shows a radial electric motor in which both ends of the energised coils used, the core (16) has a shape not a shape, with the energised coil fitted to the rotor. There is a permanent magnet inner stator (17) fixed to the outer permanent magnet stator Figure 10 shows the rotor fitted with permanent magnets in the circumference of the rotor with alternating magnetic poles facing outwards, and the stator with coil windings around the stator to give two magnetic poles on the inner face of the stator using both ends of the magnetic core (19).

Figure 11 shows the rotor fitted with permanent magnets in the circumference of the rotor with the same magnetic poles facing outwards, and the stator with coil windings around the stator to give two magnetic poles on the inner face of the stator using both ends of the magnetic core (19).

Figure 12 shows the side view application of the improved electric motor fitted to the front wheel of a bike, with the dust cover (21) fitted.

Figure 13 shows the front view application of the improved electric motor fitted to the front wheel of a bike, with the dust cover (21) fitted.

15 DESCRIPTION OF PRIOR ART This "Improved Electric Motor" is intended to overcome the deficiency of the standard electric motor, (Figures 1 and which only uses the outside of the energised segment, (Figures 1 2, no. 2) of the rotor to attract or repel the magnets (Figures 1 2, no. 6) in the stator (Figures 1 2, no. The rotor is made up of shaped segments (Figures 1 2, no. 2) radiating from the centre of the rotor (Figures 1 2, no. with the top of the forming the outer circumference of the rotor. The shaped segments have windings (Figures 1 2, no. 5) (usually copper wire) wound around the stem (Figures 1 2, no. 3) of the shaped segments which may be connected to a commutator (Figures 1 2, no.

4 7) in a D.C. motor, but not necessarily in a A.C. or other types of electrical motors. Every time the electrical current is allowed to pass through the wound coil (Figures 1 2, no. 5) the shaped segment (Figures 1 no. 2) becomes an electro magnet with a north and south magnetic pole. The top of the shaped segment (Figures 1 2, no. 2) is attracted or repelled by the magnets in the stator (Figures 1 2, no. but the lower stem of the shaped segment (Figures 1 2, no. 3) which is near the centre of the rotor (Figures 1 2, no. 4) is also magnetised, but is not used in any productive way to provide rotational power to the rotor. This invention addresses that problem and is an electric motor which uses both sides of the energised coil, to provide increased power and efficiency for the same amount of electrical energy used.

DESCRIPTION OF THE PREFERRED EMBODIMENT This invention in its simplest form consists of (Figure 3) a rotor with a shaft (4) passing through the centre of the rotor and at 90 degrees to the flat face of the rotor A spigot (13) may be attached to the centre of the rotor to act as a means of spreading the bearings and controlling the side ways movement of the circumference of the rotor Near the circumference of the rotor and equal distance from the centre of the rotor and equal distances apart are fixed :permanent magnets so that the north, south axis of the permanent magnets (0 are parallel to the shaft passing through the rotor All the permanent magnets are fixed so the north poles all face one side of the rotor and all the south poles face the other side of the rotor A horse shoe shaped electro magnet (11) is fitted to the stator so the ends of the energised core (11) are in l line with the arc formed by the permanent magnets fitted in the rotor The 25 coil (10) on the electro magnet (11) is wound to suit the predetermined application of the electric motor. When an electric current is passed through the coil (10) the •ends of the electro magnet are magnetised to have a South and North magnetic pole, adjacent to each other. The centre line of the permanent magnets in the rotor passes between the centre line of the ends of the energised magnetic poles with only an air gap clearance. A Hall effect electrical switch (12) system is fitted, which is activated by the permanent magnets in the rotor to change the direction of flow of the electrical current, and alternate the magnetic poles, at predetermined times, to induce a rotary motion of the rotor Describing the effect on a single permanent magnet in the rotor As the North pole of the permanent magnet rotates towards the South pole of the electro magnet (110. Unlike magnetic poles attract so the permanent magnet is attracted to the North pole on the energised magnet As it passes beneath the end of the energised pole on the energised magnet As it passes beneath the end of the energised pole the switch (12) is activated and changes the direction of the electric current, which in turn changes the South pole into a North pole, which repels the North pole on the permanent magnet forcing the rotor to rotate, this process is repeated. Although this invention is shown with only one electro magnet there could be as many electro magnets (11) as permanent magnets provided they are positioned the same way as the set up required for the single electro magnet (11) in relation to the permanent magnet in the rotor The number of permanent magnets could be one or more depending on design requirements, and the rotor could be of a suitable magnetic properties 20 material so that the magnetic poles could be permanently positioned in to the material, and not individual permanent magnets Only one switching device l (12) is required regardless of the number of electro magnets (11) used to change the direction of the electrical current. If the electro magnets (11) are wired in series the direction of the electric current, at any given time would be the same in all the 25 coils (10) used. An electronic circuit with a Linear Hall effect sensor and low voltage amplifier, to activate the switching, is used to change the direction of the electrical current fitted to the magnetic core. If the permanent magnets in the rotor were positioned so that on one side of the rotor the magnetic poles were, North, South, North, South, and continued to alternate, every pole being the opposite pole to the preceding pole. Instead of using one end of a energised magnet a shaped magnet with its own energising coil (10) was fitted both sides of the rotor The length between the centres of the permanent magnets in the rotor and the shaped energised magnets (11) fitted to both sides of the rotor is the same, both ends of the energised magnet (11) could be used to produce productive output.

Figure 10 and 11 show various combinations of this invention. The main point being that by placing the energising coil (11) around the stator circumference, and not the segments or shapes formed in the stator that not only does this save in the amount of copper wire required for the windings but produces the two magnetic poles for approximately half the current. It is also possible to put permanent magnets in the stator and by joining the illustrated permanent magnets which would give three shaped cores and positioning an energising coil (10) around the centre, then connecting the energised coil (11) to a commutator or electronic switching system would give more examples of configurations which could use this invention.

SReferring now to Figure 9 there is described the invention as applied to the type of 9 motor as previously described in Figure 2. However as shown in Figure 9 both poles of the electromagnets are utilised in the operation of the machine. The 20 electromagnets are arranged with the axis of the coil radial to the axis of rotation of the motor, there being provided on the stator an outer row of permanent magnets an inner row of permanent magnets the rotor operating between the two rows of permanent magnets. Although not illustrated it is clear the rotor is attached to a disc mounted on one end of the shaft while the two rows of 25 permanent magnets forming the stator are attached to the housing of the machine.

o*o* One of the uses of this new electric motor is to fit a bicycle wheel (fig 12, 13) on to the spigot attached to the rotor The most suitable wheel would be the front wheel (fig 12, 13), as this would leave the chain drive intact on the back wheel so the rider could pedal normally, or turn on the electric power to the electric motor in the front wheel and stop pedalling. The electric motor would propel the cycle in a forward direction. The amount of power, and therefore the speed of the cycle would be controlled by the switch (24) fitted to the cycle cross bar, or could be fitted to the handle bar. The electric motor would need to be fitted with a dust cover (21) and dust seals (22) to prevent metal and dust particles from being attracted to the permanent magnets, and restricting the air gap between the energised magnets (11) and permanent magnets Suitable electronics could be used to have the electric motor act as a generator and recharge the battery when the electric motor was not being used, and the bicycle was being used with pedal power, or going down a hill. It would be obvious that the motor described in this specification could be used as a stationary electric engine with the shaft fixed to the rotor and the bearings fitted to the outside casing (21) or to a stand with the shaft rotating and providing a power output.

Those skilled in the art would know that any combination of the above descriptions of the invention could be used to make the invention, depending on required design specification.

Claims (3)

1. An electrical machine comprising a direct current or alternating current electric motor or generator, the machine having a driving shaft, a rotor connected to the driving shaft by a radial plate adjacent one end of the driving shaft whereby the rotor is spaced radially from the shaft, the rotor having a plurality of spaced H shaped electromagnetic coils equally spaced around its circumference, each H shaped coil having a radial stem and radially spaced pole pieces, a stator on the machine, the stator including an outer circumferential portion having a first ring of equally spaced magnets co-operating with the outer radial pole pieces of the rotor with minimum air gap, said magnets all having the same pole facing inwardly, and an inner circumferential portion having a second ring of corresponding equally spaced magnets of opposite polarity co-operating with the inner radial pole pieces with minimum air gap, the direct current machine having control means to change the direction of the electric current through the coils of the electromagnet coils whereby the rotor takes advantage of the electromagnetic effect at each end of the H shaped coils. rii

2. An electrical machine comprising a direct current tor an alternating current electric motor or generator, the machine having a stator, the stator having an outer circumferential ring of equally spaced magnets each having the same pole facing inwardly, and spaced inwardly radially there from an inner circumferential ring of equally spaced magnets of opposite polarity to the first S.ring of magnets, and a rotor comprising a plurality of H shaped energised electromagnetic coils operating between the two rings of stator magnets and S* connected to a shaft whereby the pole pieces of the shaped energised 25 electromagnetic coils are influenced by the magnetic effect of the two rings of S:stator magnets, means being provided in the direct current machine to change the direction of electric current flow to the coils of the electromagnets.

3. An electrical machine substantially as hereinbefore described with reference to and as illustrated in Figure 9 of the drawings. Dated this 13 th day of June 2002 JOHN PATRICK ETTRIDGE By his Patent Attorneys COLLISON CO