JPH0951656A - Motor for electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a small-sized motor for electric vehicle excellent in cooling performance by forming a cooling path, communicating cooling water channels formed on the outer circumferential part in stator, in an end plate. SOLUTION: A stator 3 is fixed with a front end plate 5 and a rear end plate 6 and a rotor is supported in the stator 3. The rear end plate 6 is provided with an intake port 21 and discharge port 22 of cooling liquid. A cooling liquid is fed through the intake port 21 into a cooling water channel 6a thence fed into the cooling water channel 3h of stator 3. After cooling the cooling water channel 3h, the cooling liquid passes through cooling water channels 5a, 3i, 6b, 3j, 5b and 3k and flows into the cooling water channel 6c of rear end plate 6 before being discharged through the discharge port 22. With such a structure, the cross-sectional area of cooling water channel can be increased and the pressure drop of cooling liquid can be reduced. Furthermore, the contact area between the cooling liquid and stator 3 can be increased and the cooling performance of motor can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle motor with improved cooling performance.

[0002]

2. Description of the Related Art Conventionally, in a motor for an electric vehicle, the motor is cooled by water cooling or the like in order to prevent the insulating coating covering the winding from being deteriorated or burned due to heat generation of the coil. FIG. 8A is a cross-sectional view of a conventional motor. In the motor 1, a cooling jacket 2 manufactured by aluminum casting or the like is attached to the outer circumference of a stator 3. After the cooling water introduced from the inlet (not shown) passes through the cooling water passage 2a provided in the cooling jacket 2, the stator 3 is cooled by being discharged from the outlet (not shown). As a result, the coil 4 wound around the stator 3 is cooled by the cooling water via the stator 3. Reference numerals 5 and 6 denote front end plates and rear end plates attached to both ends of the stator 3, and rotatably support a rotor 8 via bearings 7 provided on the front end plate 5 and the rear end plate 6, respectively. .

In the motor 1 shown in FIG. 8A, since the cooling jacket 2 is mounted on the stator 3, the size and weight of the motor 1 increase, which hinders downsizing of the motor. Therefore, as a method for cooling the stator 3 while suppressing the weight of the motor, there is a method in which a copper pipe 9 is provided in the stator 3 and cooling water is passed through the copper pipe 9 to cool the stator 3, as shown in FIG. 8B. .

[0004]

However, as shown in FIG.
In the motor of (b), the copper pipe 9 having a relatively small cross section is used.
Since cooling water flows through the inside, a pressure loss occurs, and since the stator 3 is cooled through the copper pipe 9, the cooling performance is not good. When manufacturing this, the same number of holes as the copper pipes 9 are made in the stator 3, and after inserting the copper pipes 9 into each of them, the copper pipes 9 are expanded or mandrel expanded to improve contact with the stator 3. And so on. Therefore, there is a drawback that the cost of processing and assembling increases. On the other hand, in the motor shown in FIG. 8 (a), the motor becomes large in size as described above, and since the stator 3 is cooled through the water cooling jacket 2, it is similar to the motor shown in FIG. 8 (b). The cooling performance is not good.

An object of the present invention is to provide a motor for an electric vehicle that is small and has good cooling performance.

[0006]

An embodiment of the present invention will be described in association with FIGS. Figures 1 and 2
In the invention according to claim 1, a stator 3, a coil 4 wound around the stator 3, and a rotor 8 which is rotated by a rotating magnetic field generated in the stator 3 will be described.
And a pair of end plates 5 and 6 attached to both ends of the stator 3 and rotatably supporting the rotor 8 housed in the stator 3, and applied to a motor for an electric vehicle. Cooling water passages 3h to 3k in the rotor rotation axis direction are formed in the cooling water passages, and cooling water passages 5a and 5k that connect the cooling water passages 3h to 3k to the end plates 5 and 6 are formed.
b, 6b are formed to achieve the above-mentioned object. To explain with reference to FIG. 5, in the electric vehicle motor of the invention according to claim 2, the heat transmitted from the heat receiving portion 53 a is radiated by the heat radiating portion 5.
At least one of the pair of end plates 52, 62 is provided with a heat pipe 53 for transporting to the 3b, the heat receiving portion 53a contacts the end coil portion 4a of the coil 4 drawn to the end face side of the stator 3, and the heat radiating portion 53b serves as the cooling water passage. It is inserted in 3h.

In the electric vehicle motor according to the first aspect of the present invention, the cooling water passage 3 formed in the outer peripheral portion of the stator 3 is used.
In h to 3k, the cooling water channels 3h and 3i are connected by the cooling water channel 5a, the cooling water channels 3i and 3j are communicated by the cooling water channel 6b, and the cooling water channels 3j and 3k are communicated by the inflow water channel 5b. The cooling liquid flows through the communicating cooling water channels 3h to 3k in this order, and cools the coil 4 via the stator 3. In the electric vehicle motor of the invention according to claim 2, the heat generated in the coil 4 causes the heat pipe 53 to flow from the end coil portion 4 a to the cooling water passage 3.
It is transmitted to the cooling liquid in h.

In the meantime, in the section of the means for solving the above-mentioned problems which explains the constitution of the present invention, the drawings of the embodiments of the present invention are used to make the present invention easy to understand, but the present invention However, the present invention is not limited to the embodiment.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. -Embodiment of 1st invention- FIGS. 1-4 is a figure which shows embodiment of 1st invention of the motor for electric vehicles by this invention. 1 to 4, the same parts as those in FIG. 8 are designated by the same reference numerals. Note that parts that are not related to the description, such as coils, are omitted.
FIG. 1 is a side view of a motor. A front end plate 5 and a rear end plate 6 are attached to a stator 3, and a rotor 8 is supported inside the stator 3. 21
Reference numerals 22 and 22 denote inlets and outlets for the cooling liquid provided in the rear end plate 6, which will be described in detail later.

FIG. 2 is a sectional view of the motor shown in FIG.
(A) is an AA sectional view of the rear end plate 6 part,
(B) is BB sectional drawing of the stator 3 part, (c) is CC sectional drawing of the front end plate 5 part. FIG.
As shown in (b), the stator 3 includes a stator core 31 and side plates 32. Stator core 31
Is formed by laminating a plurality of plates, and grooves 31a, 31b, 31c and 31d are formed on the outer peripheral four faces in the rotation axis direction of the rotor 8. The side plate 32 is welded to the stator core 31 so as to cover the grooves 31a to 31d, whereby cooling water passages 3h, 3i, 3j and 3k are formed in the outer peripheral portion of the stator 3. On the other hand, the rear end plate 6 has a cooling water channel 6a that communicates the intake port 21 and the cooling water channel 3h of the stator 3, a cooling water channel 6b that communicates the cooling water channel 3i and the cooling water channel 3j, and a cooling water channel 3k and the discharge port 22. Cooling water channel 6c communicating with
Are formed respectively. The front end plate 5 has a cooling water passage 3h and a cooling water passage 3i for the stator 3.
And a cooling water passage 5b that connects the cooling water passage 3j and the cooling water passage 3k.

The flow of the cooling liquid will be described with reference to FIGS. 2 (a) to 2 (c). In the figure, the flow of the cooling liquid is indicated by an arrow. The cooling liquid flowing from the intake port 21 into the cooling water passage 6 a flows into the cooling water passage 3 h of the stator 3. The cooling liquid in the cooling water passage 3h is the cooling water passages 5a, 3i, 6b, 3j, 5
After passing b and 3k, it flows into the cooling water channel 6c of the rear end plate 6 and is discharged from the discharge port 22. In this way, the cooling liquid that has flowed in through the intake port 21 is discharged from the exhaust port 22 after cooling the stator 3.

FIG. 3 is a view for explaining the manufacturing process of the stator 3, and (a) to (d) show the respective processes. FIG.
In the step shown in (a), a silicon steel plate which is a material of the stator core 31 is die-cut into a shape as shown in FIG. 3 (a) to make a stator core plate 311. Notches 311a to 311 are formed on the outer peripheral portion of the stator core plate 311 within a range that does not affect the magnetic circuit formed in the stator core 31.
d is formed. FIG. 3B shows the steps of stacking and preloading the stator core plate, and the stator core plate 311 is stacked through the guide cylinder 33a of the lower plate 33 in the hole 311e through which the rotor 8 provided in the stator core plate 311 passes. After that, the upper plate 3
The guide tube 33a is passed through the hole 34a of No. 4 and tightened with the bolt 35. The diameter of the guide cylinder 33a is set to be larger than the portion inserted into the stator core plate 311 than the portion inserted into the hole 34a of the upper plate 34.
The upper plate 34 is tightened with bolts 35 until it comes into contact with the shoulder portion where the diameter of the guide cylinder 33a changes.
Thereby, the thickness dimension of the stator core 31 can be controlled to a predetermined value.

Next, as shown in FIG. 3 (c), the side plate 32 is fitted into the grooves 31a, 31b, 31c and 31d formed in the stator core 31, and the side 35a of the side plate 32 extending in the vertical direction in the figure and The stator 3 is formed by welding 35b to the stator core 31 with a laser beam or the like. By the way, in the conventional motor,
In order to fix the laminated stator core plates, the outer peripheral portion of the stator core 31 is welded in the axial direction. However, in the embodiment of the present invention, the welding of the side plates 32 also serves as the welding for this fixation.

The stator 3 assembled in this way is
The cooling water passages 3h to 3k are waterproofed by spraying an epoxy paint or the like on the inside of the cooling water passages 3h to 3k, or by vacuum impregnating a gap between the stator core plates 311 with an epoxy resin or the like. Further, as shown in FIG. 1, after applying liquid packing to the surface 44 where the rear end plate 6 contacts the stator core 31 and the side plate 32,
The rear end plate 6 is attached to the stator 3 to form a face seal, and a liquid packing 37 is also provided between the rear end plate 6 and the side surface of the stator 3 to waterproof the joint between the rear end plate 6 and the stator 3. It is carried out. Note that waterproofing of the joint between the front end plate 5 and the stator 3 is performed in the same manner.

In the embodiment of the present invention, the cooling water passages 3h to 3 are provided by providing the grooves 31a to 31d in the outer peripheral portion of the stator 3.
Since k is formed, it has the following advantages over conventional motors. (1) Cooling the stator 3 using a copper pipe Fig. 8
Compared with the motor of (b), the cross-sectional area of the cooling water passage can be increased, the pressure loss of the cooling liquid can be reduced, and the contact area between the cooling liquid and the stator 3 can be increased, so that the cooling of the motor can be performed. The performance can be improved. (2) Since the hollow portion for the cooling water passage is formed in the stator 3, the weight and size of the motor can be reduced. (3) Only by welding the side plates 32 to the outer circumference of the laminated stator core plates 311, the cooling water channels 3h to 3k.
As a result, the assembling cost can be reduced as compared with the motor shown in FIG. 8B. (4) Side plate 32 welded to the stator core 31
Plays a role of preventing the stator core plate 311 from being displaced. (5) Although the motor mount cannot be directly attached to the conventional frameless motor, in the embodiment of the present invention, the motor mount 40 is attached to the side plate 32 by welding or the like as shown in FIG. be able to.

-Second Embodiment of the Invention- FIGS. 5 and 6 show a second embodiment of an electric vehicle motor according to the present invention.
Is an embodiment of the invention. In FIG. 5, (a) is a side view of the motor, and (b) and (c) are cross-sectional views showing details of the E portion of (a). In the embodiment of the present invention, the front end plate 5 includes two end plates 51, 52.
The rear end plate 6 also includes two end plates 61 and 62. FIG. 5B shows the end plate 6
1 is a view showing a state before attaching No. 1 and a loop type thin pipe heat pipe (LCHP) 5 is attached to an end plate 62. FIG.
3, the heat receiving portion 53a is located on the end plate 61 side, and the heat radiating portion 5
LCH so that 3b is in the cooling water passage 3h of the stator 3.
P53 is brazed. After that, as shown in FIG. 5C, the LCH is formed on the portion where the coil 4 is bent on the end plate 61 side, that is, on the end coil portion 4a.
The heat receiving portion 53a of P53 is bent and pressed, and is kept in contact with it and hardened with varnish or the like. The end plate 6
The structure of the mounting portion between the stator 2 and the stator 2 is similar to the mounting structure between the rear end plate 6 and the stator 3 shown in FIG.

The heat generated in the coil 4 is transferred from the end coil part 4a to the heat receiving part 53a of the thin tube heat pipe 53, and is transferred from the heat radiating part 53b to the cooling liquid in the water passage 3h. In this way, the end coil portion 4a is LCHP5.
It is cooled by the cooling liquid in the cooling water passage 3h via 3. The principle of the loop-type thin tube heat pipe is disclosed in, for example, Japanese Patent Application Laid-Open No. 4-190090 and Japanese Patent Publication No. 2-35239.
Since this is a publicly known technique, it will not be described here.

FIG. 6 is a diagram showing a process of attaching the end plate 62 to the stator 3. After the LCHP 53 is brazed to the end plate 62 in the step shown in FIG. 6A, the end plate 62 is attached to the stator 3 as shown in FIG. 6B. At this time, the heat dissipation portion 53b of the LCHP 53 is inserted into the cooling water passages 3h to 3k of the stator 3. Then, as shown in FIG. 6C, LCHP53
The heat receiving portion 53a of B is bent and pressed against the end coil portion 4a. After that, the end coil portion 4a and the heat receiving portion 53a are integrally hardened with varnish or the like. Similarly, the end plate 52 is attached to the front end plate 5 side of the stator 3.

FIG. 7 shows a modification of the second embodiment of the present invention. Instead of the loop-shaped LCHP 53, FIG.
The plate-like LCHP71 as shown in FIG. A heat receiving portion 71a and a heat radiating portion 71b are provided in the LCHP 71.
A loop-shaped thin tube 71c meandering between and is formed. As shown in FIG. 7B, the heat receiving portion 7 of the LCHP 71.
1a is on the end plate 61 side (left side in the figure),
A plurality of LCHPs 71 are attached to the end plate 62 so that 1b is on the stator 3 side. At this time, LC
The heat dissipation portion 71b of the HP 71 is inserted into the water channels 3h to 3k. After that, as shown in FIG. 7C, the heat receiving portion 71a is bent so as to be wound around the end coil portion 4a, and is integrally hardened with a varnish or the like.

In the embodiment of the invention shown in FIGS. 5-7,
Coil end portions 4 drawn out on both sides of the stator 3
Since a is cooled by LCHP 53 and 71, the cooling efficiency of the coil end portion 4a is improved, and a larger current can be passed through the coil 4. As a result, the size of the motor can be reduced. In the embodiment of the invention described above, the heat of the coil end portion 4a is transferred to the cooling liquid in the cooling water passages 3h to 3k by using the LCHP 53, 71, but any heat transfer device can be used. However, for example, a general cylindrical heat pipe may be used. In addition, the heat pipe is not a cooling water channel in the stator 3,
It may be inserted into the cooling water passages 5a and 5b of the front end plate 5 and the cooling water passages 6a to 6c of the rear end plate 6.

In the correspondence between the embodiment of the invention described above and the claims, the front end plate 5, the rear end plate 6, and the end plates 51, 52, 61 and 62 are end plates, and the LCHPs 53, 71 are heat pipes. Configure each.

[0022]

As described above, according to the present invention,
Since the cooling water passage is formed in the outer peripheral portion in the stator, the cross-sectional area of the cooling water passage can be increased as compared with the conventional motor in which the water cooling pipe is provided in the stator, and the pressure loss of the cooling fluid and the cooling fluid and the stator can be reduced. The contact area with the motor can be increased, and the cooling performance of the motor can be improved. Further, since the cooling water passage which is a hollow portion is formed in the stator, the weight and size of the motor can be reduced. Further, in the invention of claim 2, the heat generated in the coil is transferred from the end coil portion to the cooling liquid in the cooling water passage by the heat pipe, so that the cooling efficiency is improved and the motor can be downsized.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a first invention of a motor for an electric vehicle according to the present invention.

2 is a cross-sectional view of the motor shown in FIG. 1, where (a) is A
-A sectional drawing, (b) is BB sectional drawing, (c) is CC sectional drawing.

FIG. 3 is a diagram illustrating a manufacturing process of the stator 3,
(A)-(d) shows each process.

FIG. 4 is a diagram of a motor in which a motor mount is attached to a side plate.

5A and 5B are views showing an embodiment of a second invention of an electric vehicle motor according to the present invention, wherein FIG. 5A is a side view of the motor, and FIGS. 5B and 5C are details of an E portion of FIG. 5A. FIG.

FIG. 6 is a diagram showing an end plate assembling process,
(A)-(c) shows each process.

FIG. 7 is a diagram showing a modified example of the embodiment of the second invention, (a) is a diagram showing an LCPH, and (b) and (c) are diagrams showing an end plate assembling process.

FIG. 8 is a cross-sectional view showing a conventional electric vehicle motor, in which (a) is a first example and (b) is a second example.

[Explanation of symbols]

 3 stator 3h-3k, 5a, 5b, 6a-6c cooling water channel 4 coil 4a end coil part 5 rear end plate 6 front end plate 8 rotor 31 stator core 31a, 31b, 31c, 31d groove 32 side plate 40 motor mount 51, 52, 61,62 End plate 53,71 Loop type thin tube heat pipe (LCHP) 53a, 71a Heat receiving part 53b, 71b Radiating part 71c Thin tube

Claims (2)

[Claims] 1. A stator, a coil wound around the stator, a rotor rotated by a rotating magnetic field generated in the stator, and the rotor attached to both ends of the stator and housed in the stator. In an electric vehicle motor including a pair of rotatably supported end plates, a plurality of cooling water passages in a rotor rotation axis direction are formed in an outer peripheral portion of the stator, and the end plates are provided with cooling water passages that communicate with each other. A motor for an electric vehicle characterized by having a water channel formed therein. 2. The electric vehicle motor according to claim 1, wherein at least one of the pair of end plates has a heat pipe for transporting heat transmitted from the heat receiving portion to the heat radiating portion, and the heat receiving portion is the stator. A motor for an electric vehicle, characterized in that it contacts an end coil portion of the coil drawn out to an end face side, and the heat radiating portion is inserted into the cooling water passage.