Electromechanical Machine Field of the Invention:

The subject matter described herein, in general, relates to an electromechanical machine and in particular relates to electromechanical machine for use as a generator or a motor.

Background of the Invention:

In general, an electromechanical machine, such as a generator or a motor, functions in accordance with the changing magnetic flux through a coil placed within a magnetic field. The magnetic field is generated by the magnets placed around the coil. The magnets may be permanent magnets or electromagnets. The magnetic flux in the coil can be changed either by moving the coil with respect to the magnets or moving the magnets with respect to the coil. The member that remains stationary is typically known as a stator, and the member that rotates is known as a rotor. The coil moving relative to the magnets can therefore be a rotor or a stator, depending on whether it is in motion or stationary in free space. The conventional electromechanical machines typically include a rotor made of a permanent magnet while the stator is made of a magnetic material and has a coil wound around it.

The electromechanical machine can be used as a generator or as a motor. When used as a generator, the coil or the magnets are rotated in order to provide a relative motion between the two. Relative motion between the coil and the magnets, in presence of the magnetic field produced by the magnets, results in a change of the magnetic flux through the coil, thereby resulting in the generation of voltage in the coil. When used as a motor, current is allowed to pass through the coil which forces the coil or the magnets to rotate relative to each other, thereby resulting in the generation of mechanical energy (i.e., torque).
Conventional electromechanical machines have low utilization of the magnetic flux generated in the stator. Their construction is such that it disallows the complete extraction of the magnetic flux generated around the coil. Hence, only a part of the magnetic flux is utilized and thus the overall efficiency of such a machine is not fully realized.

Available prior art mentions about using C core to achieve high performance, wherein one end portion of the C core faces the radial magnet and the other end portion of the C core faces the axial magnet. In the said arrangement continuous winding through out the length of the C core is not feasible while arresting all radial, axial and tangential direction. Assembling feasibility is a problem in the above said prior art.

Therefore the present invention tries to overcome the problems in the prior art.

Summary of the Invention:

An object of the present invention is to provide an electromechanical machine suited for high power density permanent magnet motors which can be used in automobile applications.

Another object of the present invention is to provide an electromechanical machine is
to provide a light weight stator by eliminating separate back iron for radial and axial
topologies.

Another object of the present invention is to provide an electromechanical machine which provides better fill factor.

Yet another object of the present invention is to render easy fabrication of the core structure for the electromechanical machine.

Further object of the present invention is to provide ease in winding of the coils of the electromechanical machine.

Yet another object of the present invention is to provide better ventilation as there is more space for air flow.

Further object of the present invention is to provide improved air gap flux density thereby providing better machine performance.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. Brief Description of the Invention:

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein

Figure. 1 shows exploded view of electromechanical machine according to the first embodiment of the present invention.

Figure 2 shows holding structure of the electromechanical machine according to the present invention.

Figure 3 shows core element of the electromechanical machine according to the first embodiment of the present invention.

Figure 3a shows perspective view of the electromechanical machine according to the first embodiment of the present invention.

Figure 3b shows top cross sectional view of the electromechanical machine according to first embodiment of the present invention.

Figure 4 shows cross sectional view of the electromechanical machine according to the first embodiment.

Figure 5 shows core element of the electromechanical machine according to the second embodiment of the present invention.

Figure 6 shows top cross sectional view of the electromechanical machine according to second embodiment of the present invention.

Figure 7 shows perspective view of the electromechanical machine according to the second embodiment of the present invention.

Figure 8 shows exploded view of electromechanical machine according to the second embodiment of the present invention.

Figure 9 shows core element of the electromechanical machine according to the third embodiment of the present invention.

Figure 10 shows top cross sectional view of the electromechanical machine according to third embodiment of the present invention.

Figure 11 shows cross sectional view of the electromechanical machine according to third embodiment of the present invention.

Figure 12 shows perspective view of the electromechanical machine according to third embodiment of the present invention.

Figure 13 shows exploded view of electromechanical machine according to third embodiment of the present invention.

Detailed description of the Drawings:

The present invention now will be described more fully hereinafter with different embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather those embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the invention to those skilled in the art.

A typical electromechanical machine functions based on the changing magnetic flux through a coil placed within a magnetic field. The magnetic field is generated by permanent magnets placed around the coil.. The magnetic flux through the coil can be changed either by moving the coil with respect to the permanent magnets or moving the permanent magnets with respect to the coil. More the change in the magnetic flux, more is the generation of energy, either in the form of electrical energy (i.e., voltage) when the machine is used as a generator, or mechanical energy (i.e., torque) when the machine is used as a motor.

The subject matter described herein is directed towards an electromechanical machine used as a generator or a motor and in particular to core structure for axial-radial flux permanent magnet motors. The said invention is especially suited for high power density permanent magnet motors which can be used in automobiles applications.

Referring to figure 1 and figure 4, the electromechanical machine described herein includes a first member 112 which is a hollow cylinder with its one end closed with a base or supporting plate. The said first member 112 is configured to rotate about a longitudinal axis passing through the centre of the said hollow cylinder base. The said hollow cylinder comprises a plurality of equally spaced radial magnets 125 along the inner wall of the cylindrical surface of the first member which produces magnetic lines of force in radial direction with reference to the longitudinal axis The said electromechanical machine also includes a* number of equally spaced axial magnets 130 placed on the base surface of the hollow cylinder 112 which produces magnetic lines of force in a direction parallel to the longitudinal axis. In another embodiment the whole hollow cylinder 112 includes a continuous magnet throughout the inner profile of the hollow cylinder i.e., covering both the side walls and base. In 'another embodiment, equally spaced radial magnets 125 is provided on the sides walls of the hollow cylinder and equally spaced axial magnets 130 on the base of the hollow cylinder and equally spaced magnets on the edges of the side wall and base of the hollow cylinder. The said magnets on the edges produce magnetic lines of force at an approximate angle of 45 degree to the longitudinal axis.

Further, the electromechanical machine includes a second member (135,210,211) mounted within the first member and having a number of core elements held together by atleast one holding structure preferably of spider shaped 210 to arrest axial and radial movement and atleast one split ring to arrest angular movement of the core elements.

Referring to figure 2, the said spider shaped holding structure 210 has a male dove tail part 5 which mates with female dove tail part 2 provided on the core element 135.

This particular arrangement arrests both axial and radial movements. A split ring 211 which is preferably a slotted teethed ring is placed on the spider shaped holding structure 210 and in between the core elements 135. The said split ring 211 arrests the angular movement of the core element(s).

Referring to figure 3, in one of the embodiment, the core element 135 is preferably L shaped structure, comprising an axial teeth and radial teeth and is wound with axial coils and radial coils respectively. Referring to figure 4 the said L core can either be laminated silicon steel sheets or powder material used for making stator core. The said radial teeth faces the radial magnet 125 and the said axial teeth faces the axial magnet 130. The said radial teeth part of the said L shaped core acts as back iron for the axial coils and the axial teeth will act as back iron for radial coils. The said L shaped core element is assembled to the said spider shaped holding structure ( which is a non magnetic material) 210 and the said split ring 211 to form a single stator unit, referred as second member which goes into the said first member 112.

The said first member 112 is assembled on to the crankshaft or machine shaft (if not mounted on engine) and tightened to crank shaft or machine shaft with a bolt. The said assembly is made with tolerances to accommodate the radial air gap and axial air gap accurately.

The said L shaped core's radial teeth and axial teeth can be varied by elongating or bending the respective teeth to accommodate more winding in the axial part as well as in the radial part. The polarity of the magnets in the radial and axial are opposite to facilitate flow of magnetic flux from a radial magnet and divides and sinks to axial magnet.

Referring to figure 5, figure 6, figure7 and figure 8, in one of the other embodiment, the core element 135 is preferably T shaped structure, comprising atleast two axial teeth and atleast one radial teeth and is wound with axial coils and radial coils respectively. The said T core can either be laminated silicon steel sheets or powder material used for making stator core. The said radial teeth face the radial magnet and the said axial teeth face the axial magnets. The said radial teeth part of the said T shaped core acts as back iron for the axial coils and the two axial teeth will act as back iron for radial coil. The flux path for this arrangement reduces the number of air gaps ( which is three in number) crossed by the total magnets, whereas a conventional motor, a"radial and two axial magnets ( on both sides) crosses six air gaps to complete it flux path.

The above said arrangement improves the thermal stability of the motor for longer duration while overloading and hence suited to use in high power density application.

The said T shaped core element 135 is assembled to the said spider shaped holding structure ( which is a non magnetic material) 210 and the said split ring 211 to form a single stator unit, referred as second member which goes into the said first member 112.

The said first member 112 is assembled on to the crankshaft or machine shaft (if not mounted on engine) and tightened to crank shaft or machine shaft with a bolt. The said assembly is made with tolerances to accommodate the radial air gap and axial air gap accurately.

The said T shaped core's radial teeth and axial teeth can be varied by elongating or bending the respective teeth to accommodate more winding in the axial part as well as in the radial part. The polarity of two axial magnets for T shaped core are same and the radial magnet polarity is kept opposite to axial magnets polarity in order to facilitate flow of magnetic flux from a radial magnet and divides and sinks to axial magnet.

Referring to figure 9, figure 10, figure 11 and figure 12, in another embodiment, the core element is preferably arrow shaped structure, comprising atleast three teeth or stem, wherein one axial teeth face the axial magnet and one radial teeth face the radial magnet and the third teeth is placed in between the radial and axial teeth and face the magnet which is placed in between the radial and axial magnet and is wound with coils respectively. The said arrow shaped core 135 can either be laminated silicon steel sheets or powder material used for making stator core. The said arrow shaped core element is assembled to the said spider shaped holding structure ( which is a non magnetic material) 210 and the said split ring 211 to form a single stator unit, referred as second member which goes into the said first member 112.

The said first member 112 is assembled on to the crankshaft or machine shaft (if not mounted on engine) and tightened to crank shaft or machine shaft with a bolt. The said assembly is made with tolerances to accommodate the radial air gap and axial air gap accurately.

The said arrow shaped core's 135 three teeth can be varied by elongating or bending the respective teeth to accommodate more winding in the axial part as well as in the radial part. The polarity of the magnets in the radial and axial are opposite to each other and in between magnet can take any polarity in order to facilitate flow of magnetic flux.

The first member 112 as described above can either be a rotor or a stator based on whether it is a rotating member or a stationary member. Similarly, the second member described above can either be a rotor or a stator based on same logic.

In an embodiment of the present subject matter, the electromechanical machine acts as a generator. When used as a generator, a torque is applied to the shaft, which rotates the first member and as a result, voltage is generated in the conducting wire provided in the second member. The voltage is used to generate current which can be drawn through the electrically conducting wire.

In yet another embodiment of the present subject matter, the electromechanical machine acts as a motor. When used as a motor, a current is applied to the conducting wire. The current acts as a torque generating current in presence of the varying magnetic flux, thus causing the first member to rotate. The rotation of the first member causes the rotation of the shaft. The rotating shaft can be used to drive any other machine or implementation that requires a mechanical energy for its working.

The electromechanical machine as described above may be used in various applications.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the claims.

We Claim:

1. An electromechanical machine comprising:

a first member having plurality of radial and axial magnets; a second member mounted within the first member; characterized in that said second member comprising:

plurality of core elements;

atleast one first means of holding the core elements to arrest the radial and axial movement of the said core elements; and

atleast one second means of holding the core elements to arrest the angular movement; wherein the electromagnetic flux generated within the said core element for the radial and axial magnets substantially links with all coils of the said same core element:

2. The electromechanical machine as claimed in claim 1, wherein the said first member is preferably a hollow cylinder with atleast one closed base.

3. The electromechanical machine as claimed in claim 1, wherein the said core element is preferably a L shaped core.

4. The electromechanical machine as claimed in claim 1, wherein the said core element is preferably a T shaped core.

5. The electromechanical machine as claimed in claim 1, wherein the said core element coil is a electrically conducting wire.

6. The electromechanical machine as claimed in claim 1, wherein the said plurality of radial magnets are equally spaced to generate a magnetic field in the radial direction.

7. The electromechanical machine as claimed in claim 1, wherein the said plurality of axial magnets are equally spaced to generate a magnetic field in the axial direction.

8. The electromechanical machine as claimed in claim 1, wherein the said core element comprises atleast one radial teeth facing atleast one of the radial magnet and atleast one axial teeth facing atleast one of the axial magnet.

9. The electromechanical machine as claimed in claim 6, wherein the said radial magnets are placed on the inner side walls of the hollow cylinder.

10. The electromechanical machine as claimed in claim 7, wherein the said axial magnets are placed in the base of the hollow cylinder.

11. The electromechanical machine as claimed in claim 1, wherein the said radial magnets have polarity opposite to axial magnets.

12. The electromechanical machine as claimed in claim 1, wherein the said first means of holding the core elements is a spider shaped holding structure comprising a male dove tail part which mates with female dove tail part provided on the core element.

13. The electromechanical machine as claimed in claim 1 and claim 12, wherein the said second means of holding the core elements is a split ring preferably a slotted teethed ring, placed on the spider shaped holding structure and in between the core elements.

14. The electromechanical machine as claimed in claim 1, wherein the said plurality of radial magnets is a continuous ring magnet or piece wise magnet.

15. The electromechanical machine as claimed in claim 1, wherein the said plurality of axial magnets is a continuous ring magnet or piece wise magnet.

16. An electromechanical machine comprising:

a first member having plurality of magnets placed in different planes such as radial magnets , axial magnets and magnets in between radial and axial magnets;

a second member mounted within the first member;

characterized in that said second member comprising:

plurality of core elements;

atleast one first means of holding the core elements to arrest the radial and axial movement of the said core elements; and

atleast one second means of holding the core elements to arrest the angular movement; wherein the electromagnetic flux generated within the said core element for the said magnets substantially links with all coils of the said same core element. 17.The electromechanical machine as claimed in claim 16, wherein the said first member is preferably a hollow cylinder with atleast one closed base. 18. The electromechanical machine as claimed in claim 16, wherein the said core element is preferably a arrow shaped core. 19.The electromechanical machine as claimed in claim 16, wherein the said core element coil is electrically conducting wire. 20. The electromechanical machine as claimed in claim 16, wherein the said core element comprises atleast one radial teeth facing atleast one of the radial magnet and atleast one axial teeth facing atleast one of the axial magnet and atleast one teeth facing the magnet placed in between the radial and axial magnets.

21. The electromechanical machine as claimed in claim 16, wherein the said radial magnets are placed on the inner side walls of the hollow cylinder.

22. The electromechanical machine as claimed in claim 16, wherein the said axial magnets are placed in the base of the hollow cylinder.

23. The electromechanical machine as claimed in claim 16, wherein the said radial magnet, axial magnet and magnet which is placed in between the radial and axial magnet can form a single piece continuous magnet.

24. The electromechanical machine as claimed in claim 16, wherein the said radial magnets have polarity opposite to axial magnets.

25. The electromechanical machine as claimed in claim 16, wherein the said magnet which is placed in between the radial and axial magnet can have polarity same as radial magnet polarity or can have polarity same as axial magnet polarity.

26. The electromechanical machine as claimed in claim 16, wherein the said first means of holding the core elements is a spider shaped holding structure comprising a male dove tail part which mates with female dove tail part provided on the core element.

27. The electromechanical machine as claimed in claim 16 and claim 26, wherein the said second means of holding the core elements is a split ring preferably a slotted teethed ring, placed on the spider shaped holding structure and in between the core elements.

28. The electromechanical machine as claimed in claim 16, wherein the said plurality of radial magnets is a continuous ring magnet or piece wise magnet.

29. The electromechanical machine as claimed in claim 16, wherein the said plurality of axial magnets is a continuous ring magnet or piece wise magnet.

30. The electromechanical machine as claimed in claim 1 and claim 16, wherein the said first member is a rotor and said second member is a stator, or said first member is a stator and said second member is a rotor.

31. The electromechanical machine as claimed in claim 1 and claim 16, wherein the said electromechanical machine is a current generating machine or a torque generating machine.

32. The electromechanical machine as claimed in any of the preceding claims I preferably for a two wheeler.

33.A electromechanical machine as substantially shown and described in the specification.