Title of Invention

"IMPROVED A.C. OR D.C. ELECTRIC MOTOR"

Abstract The improved electric motor makes use of both sides of an energised core to produce more power for a given current. In one embodiment, a disc rotor (8) has permanent magnets (9) positioned around its circumference, equal distances apart. The stator is a "U" shaped core (11) fitted with an energising coil (10), positioned so that both ends of the "U" are in-line with the arc formed by the centre of the permanent magnets (9). In another embodiment, there are two concentric permanent magnet rotors (6, 17) with a stator (2) located between them. The stator is composed of several "H" shaped cores (16), each fitted with a coil (5) on the centre of the "H". The two rotors (6, 17) are mechanically connected to each other so that they rotate around ...
Full Text The present invention relates to an improved AC or DC electric motor.
The accepted i.e. known, electric motor (fig. 1). (fig. 2), 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.
US Patent 4,731,554 discloses a ring shaped d. c. or induction motor having a ring shaped stator means and ring shaped rotor means radially spaced from the stator means on both sides thereof. Permanent magnets of the rotor means are magnetically coupled to windings on the stator means. The laminated core of the stator means has a toroid form of ferrous material and around the core a plurality of windings are wound in a single layer in a helical manner.
German Patent DE 40 42 432 A1 discloses a similar motor with two ring shaped rotors with permanent magnets and a ring shaped stator being disposed between the ring shaped rotors. The stator is build up by a meander-shaped electrical conductor, where the longitudinal side of the cross section of the conductor is disposed in parallel to the magnetic field between the permanent magnets of the rotors. With this specific meander shaped conductor a small rotor-stator-arrangement is achieved where eddy current losses are reduced in order to attain higher motor power.
German Patent DE 40 23 791 A1 discloses a stator disposed between two rotor elements, the stator having grooves in its inner and outer circumferential surface

into which an annular winding is inserted. Accordingly, the winding is disposed at the inner and outer circumferential surface of the stator.
In US Patent 4,900,965, an l-shaped stator bar is surrounded be a rotor having permanent magnets. On the inner side of the stator magnetically permeable material is provided building a magnetic flux return path. Between the l-shaped stator bars electrical conductors are randomly dispersed. The l-shape of the stator bars provides increased surface area for cooling as well as flux shielding for the windings allowing higher current flow resulting in a higher power-to-weight ratio.
European Patent 0 429 729 A1 discloses an electric machine with a disk-like armature. The armature consists of a winding formed on a soft iron core disk constituted by a strip of insulated dynamo sheet. The active portions of the armature winding extend radially over the faces or in slots in the faces.
The object of this invention is that the magnetic field generated by the coil is used in a productive way. This is achieved with the features of claimed herein using both sides of the energised core. Advantageous embodiments are shown in the appended dependent claims.
In the accompanying drawings:
Figure 1 shows the standard electric motor, with the rotor (3) made up of "T" shaped segments (3) radiating from the center of the rotor, with the top of the "T" (2) forming the outer circumference of the rotor (3), only one side of the energized coil (5) is used to provide rotation of the rotor (3).
Figure 2 shows the standard "Radial electric motor, with the "rotor" (3) being made up of "T" shaped segments (2) facing outwardly from the center of the rotor, with only one side of the energized coil (5) being used to provide rotation of the permanent magnets (6) in the stator (1).

Figure 3 shows the plan view of a round dish "the rotor" (8) with permanent magnets (9) fitted near its circumference. In this drawing the rotor (8) rotates around a fixed shaft (4). A single "U" shaped core (11) and energizing coil (10) are fitted at the top.
Figure 4 shows the side view of figure 3, with a "U" shaped core (11) fitted with an energizing coil (10) fixed to the side of the stator (1) in line with the arc formed by the permanent magnets (9), and fitted with a dust cover (21).
Figure 5 shows the side view of the rotor (8) fitted with a wheel (18), and with two cores (11) fitted with energized coils (10) positioned either side of the top of the rotor (8).
Figure 6 shows the side view of the rotor (8), in the shaft holderstand (14) with the energised cores (11) and coils (10) fitted to the stator (1) and positioned both sides of the bottom of the rotor (8), in line with the permanent magnets (9) in the rotor (8)
Figure 7 shows a section of the plan view of the rotor (8) with the "U" shaped core (11) and the energising coil (10) positioned one side of the rotor (8), and with all the North magnetic poles facing the same side of the rotor (8). The length between the ends of the core (11) is one and a half times the length between the permanent magnets (9) fitted in the rotor (8).
Figure 8 shows a section of the plan view of the rotor (8) with the "U" shaped cores (11) and the energised coils (10) positioned both sides of the rotor (8), with alternative magnetic poles facing one side of the rotor (8), the ends of the energised core (11) line up with the permanent magnets (9) in the rotor (8).
Figure 9 shows the radial electric motor in figure 2. with both ends of the energised coils (5) used, the core (16) has a "H" shape not a "T" shape, with the energised coil (5) fitted to the center. There is a permanent magnet Inner stator (17) fixed to the outer permanent magnet stator (6), so they rotate together.

Figure 10 shows the rotor (8) fitted with permanent magnets (9), In the circumference of the rotor (8), with alternating magnetic poles facing outwards, and the stator (1) with coil windings (5) around the stator (1) to give two magnetic poles on the inner face of the stator (1), using both ends of the magnetic core (19).
Figure 11 shows the rotor (8) fitted with permanent magnets (9), in the circumference of the rotor (8), with the same magnetic poles facing outwards, and the stator (1) with coil windings around the stator (1) to give two magnetic poles on the inner face of the stator (1), 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.
The "Improved Electric Motor" of this invention is intended to over come the deficiency of the standard electric motor, (figure. 1 & 2), which only uses the outside of the energised segment, (figure 1 & 2, no.2) of the rotor to attract or repel the magnets (figure 1 & 2, no.6) in the stator (figure 1&2, no. 1). The rotor is made up of "T" shaped segments (figure 1 & 2, no.2) radiating from the center of the rotor (figure 1 & 2, no.4), with the top of the "T" forming the outer circumference of the rotor. The "T" shaped segments have windings (figure I & 2, no.5) (usually copper wire) wound around the stem (figures 1 & 2, no.3) of the " T " shaped segments which may be connected to a commutator (figures I & 2, no.7). In a D.C. motor, but not necessarily in an A.C. or other types of electrical motors. Every time the electrical current is allowed to pass through the wound coil (figure I &2, no.5) the "T" shaped segment (figure I & 2, no.2) becomes an electro magnet with a north and south magnetic pole. The top of the" T" shaped segment (figure I &2, no.2) is attracted or repelled by the magnets in the stator (figure 1 & 2, no.6), but the lower stem of the "T" shaped segment (figure I & 2, no.3) which is near

the center of the rotor (figure I & 2, no.4) is also magnetized, 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.
This Invention in its simplest form consists of (fig.3) a rotor (8) with a shaft (4) passing through the center of the rotor (8), and at 90 degrees to the flat face of the rotor (8). A spigot (13) may be attached to the center of the rotor (8) to act as a means of spreading the bearings (15), and controlling the side ways movement of the circumference of the rotor (8). Near the circumference of the rotor (8) and equal distance from the center of the rotor (8), and equal distances apart are fixed permanent magnets (9) so that the north, south axis of the permanent magnets (9) are parallel to the shaft (4) passing through the rotor (8). All the permanent magnets (9) are fixed so the north poles all face one side of the rotor (8), and all the south poles face the other side of the rotor (8), A horse shoe shaped electro magnet (11) is fitted to the stator (1) so the ends of the energised core (11) are in line with the arc formed by the permanent magnets (9) fitted in the rotor (8). The 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 (11), are magnetized to have a South and North magnetic pole, adjacent to each other. The center line of the permanent magnets (9) in the rotor (8) passes between the center line of the ends of the energised magnetic poles (11), with only an air gap clearance. A Hall effect electrical switch (12) system is fitted, which is activated by the permanent magnets (9) in the rotor (8) 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 (8). Describing the effect on a single permanent magnet in the rotor (8). As the North pole of the permanent magnet (9) rotates towards the South pole of the electro magnet (11), Unlike magnetic poles attract, so the permanent magnet (9) is attracted to the North pole on the energized magnet (11). As it passes beneath the end of the energized pole (11), the switch (12) is activated and changes the direction of the electnc current, which in turn changes the South pole into a North

pole, which repels the North pole on the permanent magnet (9), forcing the rotor to rotate, this process is repeated. Although this invention is shown with only one electro magnet (11), there could be as many electro magnets (11) as permanent magnets (9). Provided they are positioned the same way as the set up required for the single electro magnet (11) in relation to the permanent magnet (9) in the rotor (8). The number of permanent magnets (9) could be one or more depending on design requirements, and the rotor (8) could be of a suitable magnetic properties material so that the magnetic poles could be permanently positioned in to the material, and not individual permanent magnets (9). Only one switching devise (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 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 (9) in the rotor (8) were positioned so that on one side of the rotor (8) the magnetic poles were, North, South, North, South, and continued to alternate, every pole being the opposite pole to the proceeding pole. Instead of using one end of a energised magnet (11). A " U " shaped magnet (11), with its own energizing coil (10) was fitted both sides of the rotor (8). The length between the centers of the permanent magnets (9) in the rotor (8), and the" U " shaped energized magnets (11) fitted to both sides of the rotor (8) is the same, both ends of the energized magnet (11) could be used to produce productive output.
Figures 10 and 11 show various combinations of this invention. The main point being that by placing the energising coil (11) around the stator (1) circumference, and not the segments or "T" shapes formed in the stator (1), 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 (1) and by joining the illustrated permanent magnets (9) which would give three "U" shaped cores (11), and positioning an energising coil (10) around the center, then connecting the energised coil (11) to a

commutator or electronic switching system (12), would give more examples of configurations which could use this invention.
One of the uses of this new electric motor is to fit a bicycle wheel (fig 12, 13) on to the spigot (13), attached to the rotor (8). 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 propell 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 (9). 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 (14), with the shaft (4) rotating and providing a power output Modifications are possible within the scope of the appended claims.




I CLAIM:
1. An improved AC or DC electric motor having a rotor and a stator, energised
coils positioned circumferentially around the rotor, permanent magnets in
the stator, and a switching device to change the direction of electrical
current through the energised coils, wherein the stator comprises a
permanent magnet inner stator fixed to the inner stator, the rotor with the
energised coils operating between the inner stator, and the outer stator,
characterised in that each coil is wound on an H shaped core and that the
H shaped core has a radial stem and magnetic pole pieces at each end of
the stem, with the energised coil fitted to the center of the H shaped core
and the pole pieces being radially positioned forming the circumference of
the rotor whereby both sides of the energised coil are used to be attracted
or repelled by the magnets of the inner stator and the outer stator.
2. An improved AC or DC electric motor as claimed in claim 1 wherein the
switching device comprises a Hall effect switch.
3. An improved AC or DC electric motor as claimed in claim 1 wherein the
permanent magnet inner stator and the permanent magnet outer stator
rotate together, the energised coils being preferably fixed.
4. An improved AC or DC electric motor as claimed in claim 1 wherein the
number of permanent magnets is more than one.


Documents:

abstract.jpg

in-pct-2000-00307-del-abstract.pdf

in-pct-2000-00307-del-claims.pdf

in-pct-2000-00307-del-correspondence-others.pdf

in-pct-2000-00307-del-correspondence-po.pdf

in-pct-2000-00307-del-description (complete).pdf

in-pct-2000-00307-del-drawings.pdf

in-pct-2000-00307-del-form-1.pdf

in-pct-2000-00307-del-form-19.pdf

in-pct-2000-00307-del-form-2.pdf

in-pct-2000-00307-del-form-3.pdf

in-pct-2000-00307-del-form-5.pdf

in-pct-2000-00307-del-gpa.pdf

in-pct-2000-00307-del-pct-101.pdf

in-pct-2000-00307-del-pct-210.pdf

in-pct-2000-00307-del-pct-304.pdf

in-pct-2000-00307-del-pct-401.pdf

in-pct-2000-00307-del-pct-408.pdf

in-pct-2000-00307-del-pct-409.pdf

IN-PCT-2000-307-DEL-Form-4-(05-08-2009).pdf


Patent Number 214942
Indian Patent Application Number IN/PCT/2000/00307/DEL
PG Journal Number 10/2008
Publication Date 07-Mar-2008
Grant Date 18-Feb-2008
Date of Filing 01-Nov-2000
Name of Patentee ETTRIDGE , JOHN PATRICK
Applicant Address 53 BRANKSOME TERRACE, DOVER GARDENS., SOUTH AUSTRALIA 5048, AUSTRALIA
Inventors:
# Inventor's Name Inventor's Address
1 ETTRIDGE , JOHN PATRICK 53 BRANKSOME TERRACE, DOVER GARDENS., SOUTH AUSTRALIA 5048, AUSTRALIA
PCT International Classification Number H02K 7/14
PCT International Application Number PCT/AU99/00261
PCT International Filing date 1999-04-08
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 PR7502 1998-12-03 Australia
2 PR3010 1998-04-16 Australia