JP2011125127A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an axial gap motor in which a rotor and a stator are oppositely arranged in a motor shaft direction, wherein a field coil is formed on a gap (space) between the inner circumference of the stator and the motor shaft. <P>SOLUTION: The field coil 2 which is formed by longitudinally winding a flat wire 21 in the motor shaft direction and winding it like a stack in a plurality of stages is formed in the gap between the inner circumferential end of the stator 1 and the motor shaft, and a spatial occupied rate of the field coil 2 is reduced and the field coil 2 is provided in the space even if the space between the inner circumferential end of the stator 1 and the motor shaft is small. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a motor having an axial gap structure in which a rotor and a stator are opposed to each other in the motor axial direction, and more particularly to a field coil thereof.

  Conventionally, when a motor having an axial gap structure is provided with one rotor and one stator, each of the rotor magnetic pole and the stator magnetic pole is disposed in the circumferential direction on the end faces of the rotor and the stator facing each other. The rotor magnetic pole is formed by a salient pole or permanent magnet provided in the circumferential direction on the yoke of the rotor. The stator magnetic poles are formed by teeth (saliency poles) of each phase arranged in the circumferential direction on the yoke of the stator, and the stator magnetic poles are magnetically It is excited to N pole or S pole in units of magnetic poles so that the position moves in the circumferential direction. Then, due to the magnetic action of the stator magnetic pole and the rotor magnetic pole, the rotor rotates and the motor shaft rotates.

  In addition, in this type of axial gap structure motor, a stator is disposed between rotors supported on a motor shaft, and stator magnetic poles excited in the circumferential direction are provided on both end faces of the stator by, for example, three-phase AC power feeding. Some have formed and rotated both rotors. In this case, it has been proposed that stators are further arranged outside the motor axial direction of each rotor, and field coils are provided on the stators to generate field magnetic flux (for example, Patent Document 1 (abstract, [0021]-[0022], see FIG.

  By the way, when the stator magnetic poles on both end faces of the stator are alternately excited to the north and south poles by the three-phase alternating current power supply (pulse power supply), the motor becomes thicker in the axial direction, becomes larger, and increases in mass.

  Therefore, the present applicant has already arranged a motor having an axial gap structure having a small output, a large output, and a stator having a stator disposed between the two rotors attached to the motor shaft, which has dramatically reduced the thickness in the motor shaft direction. An invention has been filed (Japanese Patent Application No. 2009-011523).

  FIG. 4 is an exploded perspective view showing a schematic configuration of an example of the axial gap structure motor of the applicant of the present application, and there are two axial gap structure motors 101 on the motor shaft 102 indicated by the axis m. Disc-shaped yokes 131 of the rotors 103a and 103b are axially attached to the motor shaft 102 at intervals from the output side, and one stator 104 is disposed between the rotors 103a and 103b.

  The stator 104 has a disk-shaped yoke 141 as a stator core, and the motor shaft 102 passes through the central hole 142 having a large diameter of the yoke 141 in a loosely inserted state.

  Further, the cylindrical magnetic path forming member 105 passes through the center hole 142 in a state of being mounted on the motor shaft 102, and both end surfaces of the magnetic path forming member 105 are in contact with the end faces 131a and 131b of the rotors 103a and 103b. A magnetic path forming member 105 is connected to the rotors 103a and 103b to form a magnetic path between the rotors 103a and 103b. The yokes 131 and 141 are made of a soft magnetic material. Moreover, the broken line arrow of FIG. 4 shows the magnetic path through which magnetic flux passes.

  Further, in the rotors 103a and 103b, for example, eight rotor magnetic poles 106 are disposed on the end surfaces 131a and 131b facing the stator 104 at equal intervals in the circumferential direction. In the stator 104, for example, 12 stator magnetic poles 107a that are excited to the S pole are arranged at equal intervals on one end surface 141a that faces the rotor 103a, and N on the other end surface 141b that faces the rotor 103b. Twelve stator magnetic poles 107b excited by the poles are arranged at equal intervals in the circumferential direction.

  FIGS. 5A and 5B show one end surface 141a and 141b of the stator 104, and the stator magnetic pole 107b on the other end surface 141b facing the rotor 103b is more circumferential than the stator magnetic pole 107a on each one end surface 141a. The stator magnetic poles 107 a and 107 b are magnetically connected by a yoke 141. In this case, when the stator 104 is viewed from the direction of the motor shaft 102, the stator magnetic pole 107b is located between the stator magnetic poles 107a, and the motor 101 is equivalent to a state in which the number of magnetic poles of the stator 104 is doubled to 24. .

  Then, the motor 101 is concentratedly wound around the stator magnetic poles 107a and 107b of the stator 104 by three-phase driving so that the coils 108 in FIGS. 5A and 5B are A phase, B phase, C Excited and driven in phase order. At this time, the motor 101 includes a stator 104, two rotors 103a and 103b disposed on both end surfaces in the axial direction, and a magnetic path forming member 105 that forms a magnetic path in the axial direction of the rotors 103a and 103b. A solid magnetic path is formed in which the magnetic flux indicated by the broken-line arrow in FIG. 4 advances in the axial direction and the circumferential direction.

  In the stator 104, all the stator magnetic poles 107a on one end surface 141a are excited to the S pole, and all the stator magnetic poles 107b on the other end surface 141b are excited to the N pole. Further, by disposing the arrangement positions of the stator magnetic pole 107a and the stator magnetic pole 107b in the circumferential direction, when the motor 101 is viewed from the axial direction, the other end face 141b side is located between the S pole stator poles 107a on the one end face 141a side. The N-pole stator magnetic pole 107b is located, and as described above, the state is equivalent to the case where the number of magnetic poles of the entire stator 104 is doubled.

  In this case, for example, the magnetic flux passing through the N-pole rotor magnetic pole 106 of one rotor 103a is the S-pole on one end face 141a of the yoke 141 of the stator 104, and the N-pole on the other end face 141b of the yoke 141 shifted in the circumferential direction. The three-pole magnetic path passes through the S pole of the other rotor 103b and the magnetic path forming member 105 and returns to the N pole of the one rotor 103a.

  The magnetic flux passes through the yoke 141 of the stator 104 in one direction, and the magnetic path in the circumferential direction of the yoke 141 becomes shorter as the number of magnetic poles increases, in other words, the number of magnetic fluxes passing through the yoke of the stator 104, in other words, the yoke. 141 magnetic path cross-sectional area becomes small. Therefore, the axial thickness of the stator 104 can be drastically reduced, and the motor 101 having the axial gap structure is formed in a small (thin) and light weight that has not been conventionally provided.

JP 2007-37342 A

  In the case of the motor described in Patent Document 1, it is necessary to further provide a stator on the outside of the rotor in order to provide the field coil, and accordingly, the motor becomes large and heavy.

  Therefore, it is conceivable to provide the field coil in the gap (vacant space) between the inner peripheral end side (center hole side) of the stator between the rotors and the motor shaft. When a field coil is formed using windings), the field coil becomes large due to a gap between the windings, the space occupation ratio is large, and it is not easy to provide a field coil in the empty space. .

  4 and 5 also, the excitation polarity of the coil 108 is set in the empty space between the inner peripheral end of the stator 104 and the motor shaft (actually the magnetic path forming member 105). If the field coils for exciting the stator magnetic poles 107a and 107b with the same polarity are provided, the amount of magnetic flux can be increased and the output of the motor 101 can be increased. If the output is the same, the motor 101 can be made more compact. However, how to form the field coil is an important issue.

  Similarly, in the case of a motor having an axial gap structure having one rotor and one stator, it is desirable to provide a field coil in an empty space between the inner peripheral end of the stator and the motor shaft. An important issue is how to form the magnetic coil.

  An object of the present invention is to provide a field coil in a gap (vacant space) between the inner peripheral end of the stator and the motor shaft in a motor having this type of axial gap structure. The purpose is to improve the assembly of the coil.

  In order to achieve the above-described object, a motor of the present invention is an axial gap structure motor in which a rotor and a stator are arranged to face each other in the motor axis direction, and is provided between the inner peripheral end of the stator and the motor shaft. A field coil formed by winding a rectangular wire in the longitudinal direction in the motor shaft direction in the gap and further winding it in a plurality of stages is provided (Claim 1).

  Further, the field coil of the motor of the present invention is characterized in that the winding start and the winding end pass between the stator magnetic poles from the same coil end surface side in the motor axial direction (Claim 2).

  In the case of the motor according to the first aspect of the present invention, the field coil provided in the gap (empty space) between the inner peripheral end of the stator and the motor shaft uses a rectangular wire instead of a general round wire. Then, the rectangular wire is wound in the motor shaft direction by edgewise winding in the vertical direction, and is further formed by being overlapped in a plurality of stages.

  In this case, unlike the round wire, the flat wire can be wound without a gap between the wires. In addition, since the flat wire is edgewise wound in the vertical direction, the length in the motor shaft direction is shorter than that of the round wire. Furthermore, when winding a rectangular wire in the vertical direction from the inside to the outside and stacking in multiple stages, the outside winding is aligned in parallel with the inside winding so as not to deviate, and a gap due to winding deviation does not occur. Can be. For this reason, the space occupancy of the field coil is sufficiently smaller than when a round wire is used.

  Therefore, even if the empty space between the inner peripheral end side of the stator and the motor shaft is small, a field coil can be provided in the empty space, and the field coil is connected to the inner peripheral end side of the stator. A motor having an axial gap structure provided in the empty space with the motor shaft can be realized.

  In the case of the motor according to the second aspect of the present invention, since the winding start and winding end positions of the field coil are on the same coil end surface side in the motor axial direction, the lead wire processing for taking out the field coil is easy. There is an advantage that the assembling property of the field coil is improved.

1 is an exploded perspective view showing a schematic configuration of a stator including a field coil according to an embodiment of the present invention. The field coil of FIG. 1 is shown, (a), (b), (c) is the front view of a field coil, a side view, and a rear view. The field coil assembled | attached to the stator is shown, (a) is a top view of the end surface of the stator with which the field coil was assembled | attached, (b) is sectional drawing of the AA line of (a). It is a perspective view of the decomposition | disassembly state which abbreviate | omitted some motors of the axial gap structure to which the stator of FIG. 1 is applied. (A), (b) is a top view of one end surface of the other of the stator of the motor of FIG.

  Next, in order to describe the present invention in more detail, an embodiment will be described in detail with reference to FIGS.

  FIG. 1 shows a schematic configuration of a stator 1 that can be used for the stator 104 of the motor 101 of FIG. 4, for example. The stator 1 has a disk-shaped yoke 10 as a stator core, and the yoke 10 has a large central hole. 11, for example, the motor shaft 102 of FIG.

  In the yoke 10, for example, 12 stator magnetic poles 12a excited at the S pole are arranged at equal intervals in the circumferential direction on one end face 10a facing the rotor 103a in FIG. 4, and face the rotor 103b in FIG. On the other end face 10b, 12 stator magnetic poles 12b excited to the N pole are arranged at equal intervals in the circumferential direction so as to be positioned between the stator magnetic poles 12a. A concentrated winding exciting coil 13 corresponding to the coil 108 in FIG. 4 is mounted on each stator magnetic pole 12a, 12b. In FIG. 1, only the exciting coil 13 of the stator magnetic pole 12a is shown, and each exciting coil 13 is wound around a resin bobbin 14 attached to the stator magnetic pole 12a.

  The field coil 2 generates a field of constant magnetic flux on the end face 10a side and the end face 10b side by direct current power supply, and makes a certain number of turns in a circular shape in the motor shaft direction with the rectangular wire 21 in the vertical direction and continuous winding. Further, it is formed by winding in two stages.

  2A, 2B, and 2C are a plan view and a side view of one coil end face (front face) 2a of the field coil 2, and a plan view of the other coil end face (back face) 2b. When the coil end surface on the end surface 10a side of the coil 10 is one coil end surface 2a and the coil end surface on the end surface 10b side of the yoke 10 is the other coil end surface 2b, the field coil 2 has the rectangular wire 21 in the vertical direction and the coil end surface 2b side. A certain number of windings are performed by edgewise winding in the motor axis direction, and when the coil end surface 2a is reached, it is continuously wound around the outer periphery toward the coil end surface 2b, thereby being wound in two stages. Yes.

  In this case, the flat wire 21 can be wound without a gap between the wires such as a round wire. Moreover, since the rectangular wire 21 is edgewise wound in the vertical direction, the length of the field coil 2 in the motor axial direction is shorter than that of the round wire. Further, when the flat wire 21 is wound in the vertical direction from the inner side to the outer side and overlapped in two steps, the outer winding is aligned in parallel with the inner winding so as not to be displaced, and a gap due to the winding deviation occurs. Can not be. Therefore, the space occupation ratio of the field coil 2 can be made sufficiently smaller than when a round wire is used.

  The diameter of the field coil 2 and the number of turns for one stage are set in consideration of the empty space between the inner peripheral end side (center hole 11 side) side of the yoke 10 and the motor shaft. In the case of the motor 101 in FIG. 4, the magnetic path forming member 105 is attached to the motor shaft, so that in reality, between the inner peripheral end of the yoke 10 (the end on the center hole 11 side) and the outer periphery of the magnetic path forming member 105. Set in consideration of free space.

  By the way, the winding start 2s and winding end 2e of the field coil 2 are both located on the coil end surface 2b, and the lead wires 22s and 22e of the winding start 2s and winding end 2e are bent from the coil end surface 2b to the coil end surface 2a side. It is bent in the radial direction at the approximate center.

  Further, the field coil 2 is accommodated in a non-excited case 30 such as a hollow annular lateral resin having an outer peripheral cylinder 31a and an inner peripheral cylinder 31b, and the lead wires 22s and 22e are a pair of inner sides of the outer peripheral cylinder 31a. The guide groove 32 is fitted.

  And the field coil 2 accommodated in the case 30 is assembled | attached to the stator 1, and the field coil 2 is provided in the state accommodated in the case 30 in the said empty space. The magnetic path forming member 105 and the motor shaft are located on the inner peripheral side from the case 30.

  3A shows an end face 10a in a state in which the field coil 2 is assembled to the stator 1, FIG. 3B shows a cross section of the AA line portion, and the lead wires 22s and 22e are yokes 10 respectively. Are drawn out to the same end face 10a, and are drawn out through the stator magnetic poles 12a.

  Therefore, in the case of the present embodiment, the field coil 2 is formed by reducing the space occupancy rate by the two-stage overlapping winding obtained by edgewise winding the rectangular wire 21, and the field coil 2 is formed at the inner peripheral end of the stator 1. A motor having an axial gap structure with a field coil can be realized by providing an empty space between the motor side and the motor shaft.

  The flat wire 21 can be wound in two stages by continuous winding by starting winding from the inner periphery side by edgewise winding and moving to the outer periphery. In this case, there is no joint in the middle of the field coil 2, there is an advantage that the connection is unnecessary, and the work and parts for that purpose can be omitted.

  Moreover, since the field coil 2 can be made into what is called a cassette type by accommodating in the case 30, handling is easy. Further, there is an advantage that the space factor of the field coil 2 in the case 30 can be increased by making the case 30 thinner.

  Furthermore, since the winding start 2s and the winding end 2e of the field coil 2 are aligned with the same coil end surface 2b, the lead wires 22s and 22e of the winding start 2s and the winding end 2e can be easily taken out from the motor. In addition, since the work of assembling the field coil 2 can be performed on the one end face 10a side, there is an advantage that the assembling property is improved. In addition, since the lead wires 22s and 22e are arranged along the yoke surface between the stator magnetic poles 12a, the lead wires 22s and 22e can be easily temporarily held by being sandwiched by a bobbin or the like when the stator 1 or the motor is assembled. As a result, there are advantages that the assemblability is improved and the number of parts required for manufacturing can be reduced.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. A motor having an axial gap structure in which the member 105 is omitted, or an axial gap structure formed by, for example, the rotor 103a and the stator 104 of FIG. 4 (in this case, the stator 104 includes only the stator magnetic pole 107a of the end surface 141a). The present invention can be similarly applied to a motor.

  Further, in the stator having the configuration in which the stator magnetic poles 12a and 12b are disposed on both end faces 10a and 10b as in the stator 1 of the embodiment, the field coil on the end face 10a side and the field coil on the end face 10b side are separated. In preparation for this, both field coils may be brought into contact with each other so as to be provided in an empty space between the inner peripheral end of the stator and the motor shaft. Moreover, you may connect after taking out the end surface of a line with the inner periphery coil and outer periphery coil which were made into the same winding direction, respectively.

  Further, in the above embodiment, the field coil 2 is overlapped and wound in two stages, but it is needless to say that the field coil 2 may be overlapped in a plurality of stages of three or more.

  Further, the winding start 2s and the winding end 2e of the field coil 2 may be aligned with the coil end surface 2a, and in this case, the same effect as in the case of the above embodiment can be obtained.

The number of the stator magnetic poles 12a and 12b (the number of magnetic poles) of the stator 1 and the structure of the stator 1 may be whatever. For example, the stator 1 is an annular combination of the divided cores for each stator magnetic pole 12a. Further, a split core structure including a combination of split cores for each stator magnetic pole 12b in an annular shape may be used.

  Further, the motor having an axial gap structure to which the present invention is applied may be a four-phase or more multi-phase drive motor.

  The present invention can be applied to an axial gap structure motor for various uses such as a drive motor for an electric vehicle.

DESCRIPTION OF SYMBOLS 1 Stator 2 Field coil 2a, 2b Coil end surface 2s Winding start 2e Winding end 21 Flat wire

Claims (2)

A motor having an axial gap structure in which a rotor and a stator are opposed to each other in the motor axial direction,
In the gap between the inner peripheral end of the stator and the motor shaft, there is provided a field coil formed by winding a rectangular wire in the vertical direction in the motor shaft direction, and further winding in multiple stages. A motor characterized by that. The motor according to claim 1,
The field coil has a winding start and a winding end passing between the stator magnetic poles from the same coil end face side in the motor axial direction.

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