JP2004048877A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To supply a rotary electric machine in which a cooling passage can be surely formed. <P>SOLUTION: In a motor 22 in which a stator 23 is disposed at a rotor 21 via a rotary air gap, the stator 23 includes a stator core 1 having a plurality of tees 1a protruding in a direction toward the rotor 21 in the circumferential direction, a coil 2 wound on the tees 1a, and a slot 3 of a space for housing the coil 2 formed between the coil 2 and the tees 1a and opened in a direction toward the rotor 21. Further, the stator 23 also includes a metal plate-like member 4 for forming a cooling water channel 14 by welding the opening of the slot 3 to the tees 1a so as to close the opening of the slot 3. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
[Industrial applications]
The present invention relates to a stator structure of a rotating electric machine, and more particularly, to a structure of a coil direct cooling type rotating electric machine having a function of cooling a coil by providing a cooling liquid path around a coil.
[0002]
[Prior art]
In recent years, high torque and high output of rotating electric machines, for example, AC motors, have been remarkable. On the other hand, the demand for miniaturization is becoming higher.
[0003]
Recently, synchronous motors with embedded permanent magnets in which permanent magnets are buried inside the rotor core and coils are concentratedly wound are being developed. As such a motor, for example, a motor disclosed in JP-A-2000-69717 is known.
[0004]
[Problems to be solved by the invention]
However, in order to reduce the size while obtaining high torque and high output, some cooling function is required regardless of air cooling or liquid cooling. In particular, since the heat generated by the current flowing through the coil is large around the coil of the stator, it is indispensable to perform cooling using a coolant. As a means for achieving this, for example, there is a method in which the salient poles of the stator are closed with a resin mold, and the periphery of the coil is used as a coolant passage. However, with this method, it is difficult for a motor aimed at miniaturization, especially, to have a sufficient space for a mold for molding resin. In addition, there is a problem that the sealing performance of the joint between the resin and the stator core cannot be sufficiently ensured, and the coolant leaks.
[0005]
Accordingly, an object of the present invention is to provide a rotating electric machine having a stator structure capable of reliably forming a cooling passage.
[0006]
[Means for solving the problem]
In a rotating electric machine in which a stator is arranged on a rotor via a rotating gap, the stator is formed between a stator core having a plurality of teeth projecting in the rotor direction in a circumferential direction, a coil wound around the teeth, and the teeth. And a slot that opens in the direction of the rotor. A metal plate-like member that forms a cooling fluid flow passage by welding to the teeth so as to close the opening of the slot.
[0007]
[Action and effect]
By providing a plate-shaped member that forms a cooling fluid flow passage by welding to the teeth so as to close the opening of the slot, a flow passage that does not leak the cooling fluid can be formed. At this time, the flow path can be formed without using a mold for forming the resin, and the flow path of the cooling fluid that prevents leakage even for a small rotating electric machine can be formed.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
In the first embodiment, as the rotating electric machine, for example, a motor 22 including a rotor 21, a stator 23 arranged outside the rotor 21, and a case 7 accommodating them is used. FIG. 1 shows a configuration of a longitudinal section of the motor 22.
[0009]
The rotor 21 includes a permanent magnet 13 embedded so as to penetrate in the axial direction. The rotor 21 is configured to be rotatable by arranging the stator 23 on the outer peripheral side of the rotor 21 via a rotation gap. The stator 23 has a cylindrical shape, and is formed by laminating a plurality of magnetic thin steel plates punched in the same shape in the axial direction.
[0010]
A cylindrical member 6 having an inner surface having the same diameter as the inner peripheral surface 1c of the stator 23 is disposed at both axial ends of the stator 23. The stator 23, here the stator core 1 and the plate-shaped member 4 described later, and the cylindrical member 6 are joined by welding at a joint 6a, which is a contact portion between them, and between the cylindrical member 6 and the case 7 The closed space 8 is formed. The closed spaces 8 are formed at both ends of the stator 23, and one is a closed space 8a on the supply side and the other is a closed space 8b on the discharge side. A cooling water intake port 9 penetrating the case 7 is provided in the supply-side closed space 8a, and a cooling water intake port 10 is provided in the discharge-side closed space 8b. Here, the cooling water inlet 9 and the cooling water outlet 10 are formed at symmetrical positions when viewed from the center of the motor 22.
[0011]
With this configuration, the cooling water is supplied from the cooling water intake 9 to the motor 22 and flows in the axial direction through the cooling water flow path 14 formed in the stator 23 through the closed space 8a on the supply side as described later. . The cooling water cools the stator 23, particularly the coil 2, when flowing through the cooling water flow path 14. Thereafter, the cooling water flows into the closed space 8b on the discharge side, and is discharged from the cooling water outlet 10 to the outside of the motor 22.
[0012]
FIG. 2 shows the configuration of the stator 23 of such a motor 22.
[0013]
The stator 23 includes a stator core 1 having a cylindrical shape formed by arranging divided cores evenly divided in a circumferential direction, and a coil 2 wound around a tooth 1 a which is a part of the stator core 1 and protrudes toward the rotor 21. I do. One tooth 1a is formed for one divided core, and a slot 3 formed of a space extending in the axial direction is formed between adjacent teeth 1a in the circumferential direction. The coil 2 wound around the tooth 1a by concentrated winding is accommodated in the slot 3.
[0014]
Further, the cooling water flow path 14 is formed by providing a plate-shaped member 4 for connecting the tips of the teeth 1a adjacent in the circumferential direction, and sealing the slot 3 in the radial direction using the plate-shaped member 4. Here, a protruding portion 1b that protrudes in the circumferential direction is provided at the tip of the tooth 1a, and the protruding portions 1b are connected by the plate-shaped member 4. Further, by forming the plate-shaped member 4 from metal and welding the protruding portion 1b and the plate-shaped member 4, it is possible to form the cooling water flow path 14 in which cooling water leakage is prevented.
[0015]
At this time, since the inner peripheral surface 1c of the stator core 1 formed by combining the divided cores is formed in a circular shape, the cross section of the tip of the tooth 1a is formed so as to draw an arc. Therefore, when the circumferential width of the plate-shaped member 4 is relatively large, the plate-shaped member 4 has an arc shape that is concentric with and has the same diameter as the inner peripheral surface 1c formed by the tip of the tooth 1a. preferable. However, when the distance between the teeth 1a is sufficiently small, the shape may be linear.
[0016]
Next, the effect when the rotating electric machine, here the motor 22, is configured as in the present embodiment will be described.
[0017]
A stator 23 is a space for accommodating a stator core 1 having a plurality of teeth 1a in a circumferential direction, a coil 2 wound around the teeth 1a, and a coil 2 formed between the teeth 1a, and a slot opened toward the rotor 21. 3 is provided. Further, a plate-like member 4 made of metal forming the cooling water flow path 14 by welding to the teeth 1a so as to close the opening of the slot 3 is provided. This makes it possible to form the cooling water flow path 14 in which cooling water leakage is prevented, and to easily form the cooling water flow path 14 even for a small rotating electric machine 22 since a resin filling mold or the like is not used in the configuration. Can be formed.
[0018]
In addition, at least one of the axial ends of the stator 23 is provided with a cylindrical member 6 which is concentric with the stator 23 at both ends and which is joined to the teeth 1a and the plate member 4 by welding. Thereby, it is possible to prevent the cooling water from leaking when the cooling water flows from the closed space 8 to the cooling water flow path 14.
[0019]
Further, a protruding portion 1b that protrudes in the circumferential direction from the tip of the tooth 1a is provided, and the plate-shaped member 4 is welded to the tip of the protruding portion 1b. Thereby, the welding operation can be facilitated, and the plate-shaped member 4 can be welded to an accurate position, so that the cooling water flow path 14 can flow a cooling water amount necessary for cooling. Can be formed.
[0020]
Next, a second embodiment will be described. The overall structure of the motor 22 and the structure of the stator 23 of the present embodiment are the same as those of the first embodiment. However, the cooling path constituting member 11 in which the cylindrical member 6 and the plate member 4 are integrated is used.
[0021]
FIG. 3 shows the shape of the cooling path constituting member 11 in which the cylindrical member 6 arranged at both ends in the axial direction of the stator 23 and a part of the plate member 4 for closing the slot 3 are integrated in advance. The cooling path constituting member 11 includes a portion 11a corresponding to the above-mentioned cylindrical member 6 and a portion 11b corresponding to the plate-like member 4 similarly. In the present embodiment, two cooling path components 11 having the same shape are inserted from both ends in the axial direction of the stator 23, and the tips of the portions 11b are welded near the center in the axial direction. Further, the protrusion 1b at the tip of the tooth 1a and the portion 11b are joined by welding in the axial direction, and the axial end of the stator core 1 and the portion 11a are joined by welding in the circumferential direction.
[0022]
Here, a configuration has been described in which two cooling liquid path constituting members 11 having the same shape are abutted from both ends in the axial direction of the stator 23, but the members 11 need not be the same shape. For example, only one part 11b corresponding to the plate-shaped member 4 for closing the slot may be provided, and the other part may be provided only as the part 11a corresponding to the cylindrical member 6. At this time, the cooling water flow path 14 is formed by joining the portions 11b and 11a (cylindrical member 6) of one of the axial ends of the stator 23 by welding.
[0023]
Next, effects of the present embodiment will be described. Here, the following effects can be obtained in addition to the effects of the first embodiment.
[0024]
The cylindrical member 6 is provided at both ends in the axial direction of the stator 23, and the cylindrical member 6 and a part of the plate member 4 are integrated to form the cooling liquid path constituting member 11. The plate-like member 4 is formed by combining the two members 11b of the cooling liquid path forming member 11. Accordingly, a configuration that can obtain the same effect as that of the first embodiment can be simply realized with a smaller number of components. Further, by fixing the member 11b that comes into contact at the axial middle portion of the slot 3 by welding, it is not necessary to match the cross-sectional shape of the plate-shaped member 4 with the shape of the cylindrical member 6, and the cooling water flow path 14 Sealability can be ensured.
[0025]
Further, the plate-shaped member 4 is formed integrally with one of the cylindrical members 6, and the cylindrical member 6 formed integrally with the plate-shaped member 4 and the other cylindrical member 6 are connected to the axial end of the stator 23. To each other. The above-described effects can also be obtained by welding the plate-shaped member 4 and the cylindrical member 6 not integrally formed with the plate-shaped member 4 at the axial end of the slot 3. . However, at this time, it is necessary to match the cross-sectional shape of the portion 11b (plate-like member 4) with the shape of the portion 11a (cylindrical member 6).
[0026]
A third embodiment will be described. FIG. 4 shows the configuration of the stator 23 used here. The other parts have the same configuration as the first or second embodiment.
[0027]
The plate-like member 4 that closes the slot 3 is installed on the coil 2 side of the inner peripheral surface 1c of the tooth 1a, here, at the base end of the protrusion 1b on the coil 2 side. At this time, the plate-shaped member 4 is disposed in a curved shape so as to protrude toward the coil 2 side. Also at this time, as in the first and second embodiments, the contact portions of the teeth 1a and the plate-like members 4 are joined by welding.
[0028]
Hereinafter, effects specific to the present embodiment will be described.
[0029]
By providing a projection 1b that protrudes in the circumferential direction from the tip of the tooth 1a, and welding the plate-shaped member 4 to the coil 2 side of the base end of the projection 1b, the plate-shaped member 4 and the rotating permanent magnet 13 are connected. The distance increases. As a result, when the rotor 21 including the permanent magnets 13 rotates at high speed, the magnetic flux generated by the permanent magnets 13 suppresses the eddy current loss caused by passing through the plate-shaped member 4, thereby suppressing the reduction in the efficiency of the motor 22. be able to.
[0030]
Next, a fourth embodiment will be described. FIG. 5 shows the configuration of the stator 23 of the motor 22 used here. Other parts are the same as in the first or second configuration.
[0031]
The distal end of the tooth 1a is configured to have a smaller width in the circumferential direction than portions other than the distal end. That is, in the first and second embodiments, the circumferential protrusion formed as the protruding portion 1b is configured to be a concave portion, and this concave portion is referred to as a retracted portion 1d. Here, a portion which is one step narrower than the width of the winding portion of the coil 2 at the tip of the tooth 1a is defined as a retraction portion 1d, and the retraction portions 1d of the adjacent teeth 1a are connected by the plate member 4. Also at this time, similarly to the first and second embodiments, the teeth 1a and the plate-like member 4 are joined by welding.
[0032]
In this way, the width of the tip of the tooth 1a in the circumferential direction is made smaller than the width of the winding part of the coil 2, and the plate member 4 is attached to the step between the tip of the tooth 1a and the winding part of the coil 2. By welding, workability of welding the plate-shaped member 4 to the outer peripheral side can be facilitated.
[0033]
Next, a fifth embodiment will be described with reference to FIG. Here, the configuration of the motor 22 is the same as any one of the first to fourth embodiments.
[0034]
Here, a welding member 12 thicker than a thin steel plate constituting the stator core 1 is provided at both axial end portions of the stator core 1. Here, generally, in order to effectively suppress eddy current loss, a thin steel plate for constituting a laminated core is often used having a thickness of about 0.05 to 0.5 mm. When the cylindrical member 6 or the cooling fluid path component member 11 as described in the above embodiment is fixed to one steel plate at the axial end portion of such a laminated core by welding, one end portion of the steel plate is welded. The steel sheet may be deformed, and a gap may be formed between the steel sheet and an adjacent steel sheet.
[0035]
Therefore, a thick welding member 12 for welding is provided at the axial end of the stacked stator cores 1, and the cylindrical member 6 or the cooling fluid path component member 11 is welded to the welding member 12. Here, the welding member 12 is formed of a non-magnetic metal such as stainless steel.
[0036]
Hereinafter, effects specific to the present embodiment will be described.
[0037]
The stator 23 is formed by laminating steel plates in the axial direction, and includes welding members 12 having a greater thickness than the steel plates at both axial ends. Thereby, when welding the cylindrical member 6 or the cooling path constituting member 11 to the axial end, the laminated steel plate is prevented from being deformed, and the fixing at the time of welding can be ensured.
[0038]
Further, by forming the welding member 12 from a non-magnetic metal, it is possible to suppress the leakage magnetic flux passing through the welding member 12 as much as possible, and to suppress a decrease in the output of the motor and a decrease in efficiency.
[0039]
Next, a sixth embodiment will be described. Here, the configuration is the same as that of any one of the first to seventh motors 22. However, the plate-like member 4 and the cylindrical member 6 that close the slot 3, or the cooling-fluid-path constituting member 11 that integrally realizes these functions, are formed of a nonmagnetic metal such as stainless steel. By forming the plate-shaped member 4 from a non-magnetic metal, it is possible to suppress a leakage magnetic flux and to suppress a decrease in output of the motor 22 and a decrease in efficiency.
[0040]
In the above embodiment, the rotating electric machine is the motor 22, but the present invention may use a generator as the rotating electric machine.
[0041]
As described above, the present invention is not limited to the above embodiment, and it goes without saying that various modifications can be made within the scope of the technical idea described in the claims.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a motor used in a first embodiment.
FIG. 2 is a configuration diagram of a stator of the motor used in the first embodiment.
FIG. 3 is a configuration diagram of a cooling liquid path constituting member used in a second embodiment.
FIG. 4 is a configuration diagram of a stator of a motor used in a third embodiment.
FIG. 5 is a configuration diagram of a stator of a motor used in a fourth embodiment.
FIG. 6 is a configuration diagram of a stator end used in a fifth embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Stator core 1a Teeth 1b Projection part 2 Coil 3 Slot 4 Plate member 6 Cylindrical member (cylindrical member)
12 Welding members (end plate)
14 cooling water channel (flow channel)
21 rotor 22 motor (rotary electric machine)
23 Stator

Claims (10)

In a rotating electrical machine in which a stator is arranged on a rotor via a rotating gap,
A stator core in which the stator includes a plurality of teeth protruding in the rotor direction in a circumferential direction;
A coil wound around the teeth,
A space for accommodating the coil formed between the teeth, and a slot opened in the rotor direction;
A metal plate-shaped member that forms a cooling fluid flow passage by welding to the teeth so as to close the opening of the slot. The rotating electric machine according to claim 1, further comprising a substantially cylindrical member concentric with the stator and joined to the teeth and the plate-like member by welding at least one of axial ends of the stator. The cylindrical member is provided at both ends in the axial direction of the stator,
One of the cylindrical member and the plate-shaped member are integrally formed,
The cylindrical member integrally formed with the plate member, and the other cylindrical member are welded to the axial end of the stator, respectively, and at the axial end of the slot, the plate member and the The rotating electric machine according to claim 2, wherein the other cylindrical member is joined by welding. The cylindrical member is provided at both ends in the axial direction of the stator,
A part of the plate-shaped member is formed integrally with each of the cylindrical members,
The cylindrical member is welded to the axial end of the stator, and the plate-like member is formed by combining the two cylindrical members, and the plate-like members are welded to each other at the axial intermediate portion of the slot. The rotating electric machine according to claim 2, wherein the rotating electric machine is joined. The rotating electric machine according to claim 1, wherein a protruding portion that protrudes in a circumferential direction from a tip of the tooth is provided, and the plate-shaped member is joined to the tip of the protruding portion by welding. The rotating electric machine according to claim 1, wherein a protrusion protruding in a circumferential direction from a tip end of the tooth is provided, and the plate-shaped member is joined to a base end of the protrusion on the coil side by welding. The width of the tip of the tooth in the circumferential direction is made smaller than the width of the winding part of the coil, and the plate-shaped member is welded to a step between the tip of the tooth and the winding part of the coil. The rotating electric machine according to claim 1. The stator core is constituted by laminating steel plates in the axial direction,
The rotating electric machine according to claim 1, further comprising an end plate having a thickness greater than that of the steel plate at both ends in the axial direction. The rotating electric machine according to claim 8, wherein the end plate is formed of a nonmagnetic metal. The rotating electric machine according to claim 1, wherein the plate-shaped member is formed of a non-magnetic metal.

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