JP2000125512A - Coil end contact cooling type dynamo-electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large-output and small and light dynamo-electric machine, while avoiding the temperature rise of a stator coil. SOLUTION: At least the coil end 2d of a stator coil is constituted by laying each axial projection, consisting of a conductor in the shape of a thin plate projecting from the end plate of a stator core in an attitude that the thickness direction is in matching with the diametrical direction of the stator core 1 on top of the other each in diametrical direction. The cooling capacity of the coil end part 2d is raised by providing the dynamo-electric machine with cooling members 8 and 9 of food thermal conductivity which have flat cooling faces sticking fast directly, while being electrically insulated, to the flat main face of the thin plate-shaped conductor on the outermost side diametrical direction or innermost side diametrical direction of this coil end 2d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a coil-end contact cooling type rotary electric machine.

[0002]

2. Description of the Related Art In a rotating electric machine, particularly in a closed type rotating electric machine, a stator coil is a main heat source, and a rise in the temperature of the stator coil causes deterioration of its insulating resin. Usually limited by cooling performance. The current density of the stator coil determines the size and weight of the rotating electric machine.

[0003] The molded motor disclosed in Japanese Patent Application Laid-Open No. H10-51989 is designed to cool a coil end of a stator coil between a radially outermost surface of the coil end and an inner peripheral surface of a housing facing the coil end. In a mold type motor that molds resin in the idle space and conducts heat from the coil end to the housing with this molded resin, a cylindrical member with good heat conductivity is inserted in close contact with the inner peripheral surface of the housing and molded. It is proposed to improve the deterioration of thermal conductivity due to high heat transfer resistance of the resin.

[0004]

However, in the above-mentioned prior art, it is difficult to eliminate the mold resin filling the coil end due to the presence of significant irregularities on the outermost surface in the radial direction of the coil end. However, the high heat transfer resistance of the molding resin limits the improvement of the coil end cooling effect.

[0005] For this reason, especially in a hermetic motor, there is a problem that the reduction in size and weight due to the improvement of the current density of the stator coil is restricted by the poor heat conductivity of the molding resin. The present invention has been made in view of the above problems, and an object of the present invention is to provide a small-sized and light-weight coil-end contact-cooling type rotary electric machine that avoids a rise in the temperature of a stator coil.

[0006]

In the coil-end contact cooling type rotating electric machine according to the present invention, at least the coil end of the stator coil has a thin plate projecting from the end face of the stator core in a position in which the thickness direction coincides with the radial direction of the core. Each of the axially projecting portions made of the conductor is overlapped with each other in the radial direction.
Then, a cooling member having good thermal conductivity having a flat cooling surface which is electrically insulated and directly adhered to the flat main surface of the radially outermost or radially innermost thin plate-shaped conductor of the coil end is provided.

That is, according to the present configuration, the coil end is formed by radially superposing the thin plate-shaped conductors projecting from the end face of the stator core in a posture in which the thickness direction coincides with the radial direction of the core. The radially outermost or radially innermost surface is a flat (accurately cylindrical) surface, which allows the flat surface of the cooling member to be in intimate contact with only a thin electrical insulator. As a result, the heat dissipation of the coil end can be significantly improved.

According to the second aspect of the present invention, in the coil-end contact cooling type rotary electric machine according to the first aspect, the cooling member is in close contact with the housing, so that the cooling member satisfactorily transmits the heat of the coil end to the housing. Alternatively, the heat of the stator core can be well transferred from the housing to the cooling member. According to the third aspect of the present invention, in the coil end contact cooling type rotary electric machine according to the first or second aspect, the cooling member is further in close contact with the end surface of the stator core, so that the heat of the stator core can be transmitted to the cooling member in a satisfactory manner. it can.

According to a fourth aspect of the present invention, in the coil-end contact cooling type rotary electric machine according to any one of the first to third aspects, the cooling member further comprises a flat outermost peripheral surface of the coil end and a flat inner peripheral surface of the housing. Since the cooling pipe is provided between the cooling pipe and the peripheral surface, the heat of the coil end and the housing can be transferred to the outside.
Further, since the cooling pipe is in close contact with the coil end and the flat surface of the housing, there is no need to complicate the shape of the cooling pipe. Further, since the cooling pipe is accommodated in an idle space between the coil end and the housing (the radial thickness of the idle space is substantially equal to the thickness of the yoke portion of the stator core), the size of the rotating electric machine is increased. Not even.

According to a fifth aspect of the invention, in the coil-end contact cooling type rotary electric machine according to any one of the first to third aspects, the cooling member further comprises an outermost peripheral surface of the coil end and an inner peripheral surface of the housing. And a metal member interposed between them to transmit heat of the coil end to the housing.
For example, the metal member is constituted by a cooling pipe through which the cooling liquid does not circulate, and the cooling pipe may or may not be filled with the cooling liquid.

According to this configuration, since the contact surface between the coil end and the housing is flat, the heat of the coil end can be transmitted to the housing with a simple cooling member. According to a sixth aspect of the present invention, in the coil end contact cooling type rotary electric machine according to any one of the first to third aspects, the housing further includes a coil end contact portion which is in close contact with a flat outermost peripheral surface of the coil end as a cooling member. Since the coil end contact portion is formed to be smaller in diameter than other portions, the heat of the coil end is satisfactorily radiated to the housing through the flat outermost peripheral surface while suppressing an increase in the number of components. be able to.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the following examples.

[0013]

Embodiment 1 An embodiment of a three-phase AC motor according to the present invention will be described. (Stator structure) First. The stator structure of the three-phase AC motor according to this embodiment will be described with reference to FIGS. FIG. 1 shows a plan view of a stator of this motor, FIG. 2 shows a front view, and FIGS.

Reference numeral 1 denotes a stator core formed by laminating thin plate-shaped electrode steel plates, and has a number of slots opened on the inner diameter side. In each slot, a star-connected three-phase two-layer wave-wound stator coil (hereinafter, also simply referred to as a coil) 2 is wound. A plate-shaped wedge 4 for preventing protrusion is fitted.
An insulator 3 for insulating the coil 2 and the core 1 from each other is inserted into the inner periphery of the slot.

The coil 2 has a linear slot conductor 21 inserted into the slot, and a transition conductor 22 formed integrally with the slot conductor 21.
Are individually connected to the same ends of a pair of slot conductors 21 inserted into slots on both sides sandwiching two slots. The coil 2 is composed of three phase coils 2a, 2b and 2c as shown in FIG.
As shown in FIG. 3, the starting conductor 21a extending in the traveling direction away from the starting ends 23 to 25 of the phase coils 2a, 2b, 2c, and the starting end 2 of the phase coils 2a, 2b, 2c.
And a return conductor portion 21b extending in the return direction approaching as viewed from 3 to 25. Therefore, the coil end portions 2d on both sides of the slot are, to be precise, composed of the end portions on both sides of the slot conductor portion 21 and the transition conductor portion 22.
As shown in FIG. 1, is bent obliquely in the circumferential direction with respect to the slot conductor 21, is bent at the center of the crossover conductor 22, and has a mountain shape at the axial end thereof. More specifically, each of the bent ends 22a is overlapped by being radially folded and overlapped at the axial end.

Hereinafter, the coil 2 will be described in more detail. As shown in FIG. 3, the coil 2 has six coil conductors 201 to 201 arranged in parallel at a distance of one slot pitch.
206, and the coil conductors 201 and 204 are the phase coils 2
a, and the coil conductors 203 and 206 are phase coils 2b
And the coil conductors 202 and 205 constitute the phase coil 2c. Each of the coil conductors 201 to 206 has a substantially rectangular cross-sectional shape that is thin in the radial direction of the stator core 1 and wide in the circumferential direction.

The n-th (n is an integer) slot conductor of the m-th (m is an integer) coil conductor is the m-th (m is an integer) coil conductor.
The first coil conductor is accommodated in a slot 180 electrical degrees away from the slot in which the (n-1) -th or (n + 1) -th slot conductor portion 21 is accommodated, that is, a slot separated by a 3-slot pitch. In addition, in the slots separated by the pitch of three slots, the (m−3) th or the (m +) th
It is housed together with the slot conductor portion 21 of the third coil conductor.

Further, among the start ends of the six coil conductors 201 to 206, the second, fourth, and sixth start ends are short-circuited to each other to be a neutral point, and the remaining first, third, and fifth start ends are three. Terminals of the phase coils 2a, 2b, 2c connected in a phase star configuration. A specific method for manufacturing the coil conductors 201 to 206 will be described with reference to the manufacturing procedure shown in FIGS.

First, as shown in FIG. 3, six coil conductors 201 to 206 are arranged in parallel at intervals of one slot pitch. The slot conductor portion 21 and the transition conductor portion 22 are each formed in a linear band shape, and the transition conductor portion 22 has an appropriate angle (here, about 60
Degrees). 23 is a coil conductor 201
24 is a starting end of the coil conductor 203;
Reference numeral 25 denotes a start end of the coil conductor 205, 26 denotes a start end of the coil conductor 202, 27 denotes a start end of the coil conductor 204, and 28 denotes a start end of the coil conductor 206.

Next, as shown in FIG.
The first six transition conductors 22 counted from the starting ends 23 to 28 of the first to second 206 are positioned at the center (indicated by a broken line in FIG. 3) so that the first slot conductor 21 is located below (by valley folding). )
Bend. In FIG. 3, each coil conductor 201
The first slot conductor portion 21 and the next slot conductor portion 21 counted from the starting ends 23 to 28 of the first to third slot conductors 206 to 206 are formed at a pitch of three slots apart from each other.
The second slot conductor 21 of the coil conductor 202 overlaps the first slot conductor 21 of the coil conductor 205, and so on. On top of
The second slot conductor 21 of the coil conductor 203 overlaps the first slot conductor 21 of the coil conductor 206.

Next, as shown in FIG.
At the center (shown by a broken line in FIG. 4), the sixth six transition conductors 22 counted from the start ends 23 to 28 of the first to second 206 are shown.
The second slot conductor 21 is folded over the third slot conductor 21 (by mountain fold, that is, in the same rotation direction as the first folding direction in the present invention).
As a result, the third slot conductor 21 of the coil conductor 201 becomes the second slot conductor 21 of the coil conductor 204.
, And similarly, the third slot conductor 21 of the coil conductor 202 overlaps the second slot conductor 21 of the coil conductor 205, and the third slot conductor 21 of the coil conductor 203 The conductor 206 overlaps below the second slot conductor 21. As a result, the third slot conductor 21 is accommodated at the same depth (the deepest position) within the slot as the first slot conductor 21 without difficulty.

Hereinafter, as shown in FIG.
By folding in the same rotation direction as the mountain fold and the valley fold, six coil conductors 201 to 206 are provided in each slot.
Housed in layers. As a result, the coil conductors 201 to 201 are bent by the number of times obtained by subtracting 1 from the number of rotor magnetic poles.
The coil 206 makes one round, and a coil for two turns is formed in two layers in the slot.

Next, as shown in FIG. 7, the sheet is folded in the direction of rotation opposite to the conventional one (ie, the last folding of the first two turns is a valley fold, so the valley fold is performed again). Thus, the subsequent slot conductor 21 can be smoothly arranged in the third and fourth layers in the slot. Subsequently, as shown in FIG. 8, the six coil conductors 201 to 206 are placed in each slot by bending in the same rotation direction as the first two turns such as valley fold, mountain fold, and valley fold.
Housed in layers. As a result, each coil conductor 2 is bent again by the number of times obtained by subtracting 1 from the number of rotor magnetic poles.
01 to 206 perform the next round, and coils for four turns are formed in four layers in the slot. Hereinafter, the required number of turns is produced in the same procedure as described above.

As a result, as shown in FIG. 8, the final crossover conductor portion 22b of each of the coil conductors 201 to 206 is about half as long as the conventional crossover conductor portion 22, and
The final transition conductor 22b of each of the coil conductors 204 to 206 is slanted in a line-symmetrical direction with respect to the other transition conductors 22 and the final transition conductor 22b. As a result, as shown in FIG. 10, the final crossover conductor portion 22b of the coil conductors 201, 204
Of the coil conductors 202 and 205 overlap, and the tip of the final crossover conductor 22b of the coil conductors 202 and 205 overlaps.
The leading end of the final crossover conductor portion 22b of 206 overlaps, and by welding these overlapping portions, a three-phase stator coil is formed. More specifically,
The coil conductors 201 to 203 are bent as shown in FIG. 9, and thereafter, as shown in FIG.
The overlapping may be formed by performing bending of steps 206 to 206, and welding may be performed.

Next, the coil 2 manufactured as described above is inserted into each slot of the stator core 1, and the starting point of the coil conductors 202, 204, 206 is short-circuited next or before the insertion of the slot, and the neutral point is set. And (Overall Structure) Next, the overall structure of the three-phase AC motor of this embodiment will be described with reference to FIGS. FIG. 11 is an axial sectional view showing the overall structure of the three-phase AC motor, and FIG.
2 is a sectional view taken along the line AA.

Reference numeral 100 denotes a can-shaped front frame (housing), 101 denotes a rear frame (housing) for closing the opening thereof, and a rotary shaft 6 on which the rotor 5 is fitted.
Is rotatably supported. Reference numeral 7 denotes a resin cover that shields an electric chamber on the outside of the rear frame 101 in the axial direction, and the electric chamber accommodates various electric components such as terminals.

In this three-phase AC motor, a copper cooling water pipe 8 is provided between a coil end portion (coil end in the present invention) 2d on the rear side of the stator coil 2 and the front frame 100, and a coil end portion 2d , The end surface of the stator core 1 and the inner peripheral surface of the front frame 100. Similarly, a cooling water pipe 9 made of copper is provided between the front-side coil end portion (coil end in the present invention) 2d of the stator coil 2 and the front frame 100. It is attached in close contact with the end surface and the inner peripheral surface of the front frame 100. However, a thin heat-resistant resin film 10 is interposed between the inner peripheral surfaces of the cooling water pipes 8 and 9 and the outer peripheral surface of the coil end portion 2d. If the enamel resin layer covering the coil end portion 2d has sufficient electric insulation, the heat-resistant resin film 1
It is also possible to omit 0.

The cooling water pipe 8 on the rear side is formed in a ring shape as shown in FIG. 12 surrounding the coil end 2d shown in FIG. 11, and the inlet 81 and the outlet 82 of the cooling water pipe 8 are And protrudes radially outward through a groove 100a recessed from the opening end of the front frame 100. 102 is a metal cover for shielding the groove 100a.

The cooling water pipe 9 on the front side is formed in a ring shape surrounding the coil end 2d shown in FIG. 11, but unlike the cooling water pipe 8, an inlet 81 and an outlet 82 are formed. Instead, it is hermetically sealed with about half of the water inside. The effects of the cooling water pipes 8 and 9 will be described below. First, since the cooling water pipe 8 satisfactorily removes the heat of the coil end portion 2d and the stator core 1 and discharges the cooling water to the outside, the temperature of each portion of the stator can be satisfactorily reduced through the coil end portion 2d.

The cooling water pipe 9 is formed by the coil end portion 2d and the stator core 1 by the so-called heat pipe effect.
And the heat can be satisfactorily transmitted to the front frame 100, and the temperature of each portion of the stator can be satisfactorily reduced through the coil end portion 2d. Next, since the cooling water pipes 8 and 9 are accommodated in an idle space between the Freon and the inner peripheral surface of the frame 100 and the outer peripheral surface of the coil end portion 2d, the motor size does not increase.

Particularly, in this embodiment, the coil end portion 2d
The surface of the outermost coil conductor becomes a flat circumferential surface,
The inner and outer peripheral surfaces of the cooling water pipes 8 and 9 can be flat circumferential surfaces, and the shapes of the cooling water pipes 8 and 9 can be simplified. (Modification) The cooling water pipe 9 can satisfactorily transfer the heat of the coil end portion 2d to the front frame 100 without sealing the liquid inside. (Modification) As shown in FIG.
It may be provided in close contact with the inner peripheral surface of the coil end portion 2d,
In addition, as shown in FIG. 14, they may be provided in close contact with both. (Modification) FIG. 15 shows a modification of the motor of the first embodiment.

This motor is different from the motor of the first embodiment shown in FIG. 11 in that the cooling water pipes 8 and 9 are omitted, and the front frame 100 and the rear frame 101 have the same diameter as the cooling water pipes 8 and 9. The inner peripheral surfaces of the front frame 100 and the rear frame 101 are coiled at a coil end portion 2d with a thin electric insulating film 10 interposed therebetween.
Is characterized in that it is brought into direct contact with the outer peripheral surface of the.

More specifically, the front frame 100
Has a stator core contact portion 100b that is in close contact with the outer peripheral surface of the stator core 1, and a coil end contact portion 100c that is in close contact with the outer peripheral surface of the front side coil end portion 2d,
The latter has a smaller diameter than the former. On the other hand, the cylindrical wall portion 101a of the rear frame 101 is
0b and the rear coil end 2
d is in close contact with the outer peripheral surface.

By doing so, for example, by cooling the front frame 100 with cooling water or the like, the heat of the coil end portion 2d is satisfactorily radiated to the cooling water, and the temperature of the stator coil 2 including the coil end portion 2d is reduced. Can be favorably reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a stator in an embodiment of a three-phase motor in which a wave winding of the present invention is applied to a stator winding.

FIG. 2 is a front view of the stator shown in FIG.

FIG. 3 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 4 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 5 is a process chart showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 6 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 7 is a process chart showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 8 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 9 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 10 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 11 is an axial sectional view showing the entire structure of the three-phase AC motor according to the first embodiment.

FIG. 12 is a sectional view taken along line AA of FIG. 11;

FIG. 13 is an enlarged partial cross-sectional view of a main part showing a modification of the first embodiment.

FIG. 14 is an enlarged partial cross-sectional view of a main part showing a modification of the first embodiment.

FIG. 15 is an overall sectional view showing a modification of the first embodiment.

[Explanation of symbols]

1 is a stator core, 2 is a stator coil, 22d is a coil end portion (coil end), 8 and 9 are cooling water pipes (cooling members), 100c is a coil end contact portion (cooling member) of the rear frame 100, and 101a is a cylindrical wall. Part (cooling member)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H603 AA11 BB01 BB07 BB12 CA01 CA05 CB03 CC03 CD02 CD06 EE21 5H609 BB01 BB12 BB19 PP02 PP06 PP09 QQ04 QQ13 QQ23 RR37 RR40 RR43 RR69 RR70 RR73

Claims (6)

[Claims] 1. A stator coil having a coil end formed by radially superposing axially projecting portions made of a thin plate-like conductor projecting from an end face of a stator core in a posture in which a thickness direction thereof coincides with a radial direction of the core. And a flat cooling surface which is electrically insulated and directly adhered to the flat main surface of the thin plate-shaped conductor radially outermost or radially innermost of the coil end to cool the coil end. A coil end contact cooling type rotating electric machine comprising: a heat conductive cooling member. 2. The coil-end contact cooling type rotary electric machine according to claim 1, wherein the cooling member is in close contact with a housing supporting the stator core. 3. The coil-end contact cooling type rotary electric machine according to claim 1, wherein the cooling member is in close contact with an end face of the stator core. 4. The coil end contact cooling type rotary electric machine according to claim 1, wherein the cooling member is provided between an outermost peripheral surface of the coil end and an inner peripheral surface of the housing. A coil-end contact cooling type rotating electric machine characterized by including a cooling pipe through which a coolant flows in a circumferential direction. 5. The coil end contact cooling type rotary electric machine according to claim 1, wherein the cooling member is interposed between an outermost peripheral surface of the coil end and an inner peripheral surface of the housing. A coil end contact cooling type rotating electric machine, comprising a metal member for transmitting heat of the coil end to the housing. 6. The coil end contact cooling type rotary electric machine according to claim 1, wherein the housing is a coil end contact portion which is in close contact with an outermost peripheral surface of the coil end as the cooling member, and wherein the stator core is provided. And a coil end contact portion formed to be smaller in diameter than the stator core support portion.