Motor

Abstract

Provided is a motor which can be downsized in the shaft direction while securing sufficient insulating properties between a coil end and a housing. A motor 1 is provided with a housing 10, a stator 20, a rotor 30, and a cylindrical insulating sealing member 40. The insulating sealing member 40 has a rotor facing part 41, a reinforcement part 42 provided at one end in the shaft direction, and a reinforcement part 43 provided at the other end in the shaft direction. The reinforcement part 42 and the reinforcement part 43 have thicknesses t1 and t2 which are larger than the thickness of the rotor facing part 41, and are equal to or larger than a gap G between the stator 20 and the rotor 30. The reinforcement part 42 and the reinforcement part 43 face the coil ends of a coil 22 on the radially outer side, and are supported by a partition wall (support part) 122 and a partition wall (support part) 132 of the housing 10 on the radially inner side.

Description

Motor

[0001] The present invention relates to a motor having a cylindrical insulating sealing member that separates a stator chamber from a rotor chamber.

[0002] 2. Description of the Related Art Conventionally, motors have been known that use a cylindrical sealing member to separate a stator chamber and a rotor chamber within a housing of the motor.

[0003] Japanese Patent Application Laid-Open Publication No. 2019-193508 (Patent Document 1) discloses a canned motor that prevents can buckling while suppressing a decrease in motor performance. The canned motor includes a rotating shaft, a rotor fixed to the rotating shaft, a stator disposed on the outer periphery of the rotor, a rotor chamber that houses the rotor, a stator chamber that houses the stator, a cylindrical can disposed between the rotor and the stator and configured to separate the rotor chamber from the stator chamber, and metal O-rings disposed on the outer periphery of both ends of the can. The can has a central portion and end portions. The end portions form stepped portions relative to the central portion of the can so as to protrude radially outward. As a result, when the end portions of the can are inserted into the stator, the stepped portions abut against stepped portions of the load-side side plate. As a result, axial movement of the can is limited, making it easy to fix the can in the axial direction.

[0004] Japanese Patent Application Laid-Open No. 2019-193508

[0005] However, the canned motor of Patent Document 1 uses a stepped portion formed on the can to easily fix the can in the axial direction, and does not propose reducing the size of the motor itself.

[0006] The present disclosure provides a motor having a cylindrical sealing member that can be made smaller in size in the axial direction while ensuring sufficient insulation between the coil end and the housing.

[0007] In order to solve the above problems, the present disclosure is configured as follows. That is, the motor according to the present disclosure includes a stator, a rotor rotatably mounted inside the stator, a housing having a stator chamber that accommodates the stator coil ends and a coolant for cooling the coil ends so as to maintain liquid-tightness with the coolant, and a rotor chamber that accommodates the rotor, and a cylindrical insulating sealing member housed in the housing, separating the stator chamber from the rotor chamber and maintaining liquid-tightness of the stator chamber. The insulating sealing member includes a rotor-facing portion that faces the rotor, a first reinforcing portion provided at one axial end and having a thickness greater than that of the rotor-facing portion, and a second reinforcing portion provided at the other axial end and having a thickness greater than that of the rotor-facing portion. The first reinforcing portion and the second reinforcing portion each have a thickness equal to or greater than the gap between the stator and the rotor. The first reinforcing portion and the second reinforcing portion face the stator coil ends radially outward. The housing has, on the radially inner side, a first support portion that supports the first reinforcing portion and a second support portion that supports the second reinforcing portion.

[0008] According to the motor of the present disclosure, it is possible to reduce the size in the axial direction while ensuring sufficient insulation between the coil end and the housing.

[0009] Fig. 1 is a cross-sectional view schematically showing a motor according to an embodiment of the present disclosure, Fig. 2 is an enlarged cross-sectional view showing an insulating sealing member of Fig. 1, and Fig. 3 is an enlarged cross-sectional view showing an insulating sealing member of a modified example.

[0010] (Configuration 1) A motor according to an embodiment of the present disclosure includes a stator, a rotor rotatably mounted inside the stator, a housing having a stator chamber that accommodates the stator coil ends and a coolant for cooling the coil ends so as to maintain liquid-tightness with the coolant, and a rotor chamber that accommodates the rotor, and a cylindrical insulating sealing member housed in the housing, separating the stator chamber from the rotor chamber and maintaining liquid-tightness of the stator chamber. The insulating sealing member includes a rotor-facing portion that faces the rotor, a first reinforcing portion provided at one axial end and having a thickness greater than that of the rotor-facing portion, and a second reinforcing portion provided at the other axial end and having a thickness greater than that of the rotor-facing portion. The first reinforcing portion and the second reinforcing portion each have a thickness equal to or greater than the gap between the stator and the rotor. The first reinforcing portion and the second reinforcing portion face the stator coil ends radially outward. The housing has a first support portion that supports the first reinforcing portion radially inward and a second support portion that supports the second reinforcing portion radially inward.

[0011] According to the above configuration, the first reinforcing portion and the second reinforcing portion, which have a relatively large thickness, face the coil ends of the stator radially outward, thereby ensuring sufficient insulation between the coil ends and the housing, and further, since the first reinforcing portion and the second reinforcing portion are supported by the first support portion and the second support portion, respectively, the size can be reduced in the axial direction.

[0012] (Configuration 2) In the motor of Configuration 1, the first reinforcing portion may be formed to be thicker radially inward. The second reinforcing portion may be formed to be thicker radially inward. The second reinforcing portion may have a thickness smaller than that of the first reinforcing portion. This allows the rotor to be easily inserted into the housing during assembly of the motor, and also allows the gap between the stator and the rotor to be smaller, thereby improving torque.

[0013] (Configuration 3) In the motor of Configuration 1, the first reinforcing portion may be formed to be thicker radially inward. The second reinforcing portion may be formed to be thicker radially outward. This allows the rotor to be more easily inserted into the housing during assembly of the motor, and further reduces the gap between the stator and the rotor.

[0014] (Configuration 4) In the motor of any one of Configurations 1 to 3, either the first reinforcing portion or the second reinforcing portion may have a chamfered portion whose radially inner end is chamfered, thereby allowing the first reinforcing portion or the second reinforcing portion to be smoothly supported by the first support portion or the second support portion when the insulating sealing member is inserted into the housing during assembly of the motor.

[0015] (Configuration 5) In the motor of any one of configurations 1 to 4, the first reinforcing portion may abut against the housing in the axial direction, which makes it easier to position the insulating sealing member when assembling the motor.

[0016] (Configuration 6) In the motor of any of Configurations 1 to 5, the first reinforcing portion may be supported by the first support portion radially inward of the second reinforcing portion, thereby further saving space and achieving a reduction in radial size.

[0017] (Configuration 7) In the motor of any one of Configurations 1 to 6, an end of either the first reinforcing portion or the second reinforcing portion may be positioned axially outward from the coil end of the stator, thereby ensuring more sufficient insulation between the housing and the coil end.

[0018] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and the description thereof will not be repeated. The dimensional ratios between the components shown in each drawing do not necessarily represent the actual dimensional ratios.

[0019] As shown in Fig. 1, the motor 1 includes a housing 10, a stator 20, a rotor 30, an insulating sealing member 40, and a shaft 50. The stator 20 and the rotor 30 each have a cylindrical outer shape and are housed in the internal space of the housing 10 via the cylindrical insulating sealing member 40. Fig. 1 shows a vertical cross section including an axial direction CL.

[0020] The housing 10 has a cylindrical housing main body 11, a cover 12, a cover 13, an annular sealing member 14, an annular sealing member 15, a stator chamber 100, and a rotor chamber 200. The cover 12 covers an opening on one side (the left side in the figure) of the housing main body 11. The cover 13 covers an opening on the other side (the right side in the figure) of the housing main body 11. The covers 12 and 13 rotatably support the shaft 50 via bearings.

[0021] Here, a method for assembling the motor 1 will be briefly described. First, the cover 12 is attached to one opening of the housing body 11. Next, the shaft 50 is assembled into the rotor 30. Next, the shaft 50, the rotor 30, the insulating sealing member 40, and the stator 20 are inserted through the other opening of the housing body 11 so as to form the predetermined arrangement shown in FIG. 1 . Finally, the cover 13 is attached to the other opening of the housing body 11, completing the assembly of the motor 1. Arrow A in the figure indicates the insertion direction of each component housed in the housing 10. Therefore, in this disclosure, the left side of the figure may be referred to as the "front end" in the insertion direction A, and the right side of the figure may be referred to as the "rear end" in the insertion direction A. From this perspective, in the insertion direction A, the cover 12 may be referred to as the "front end cover," and the cover 13 may be referred to as the "rear end cover."

[0022] The covers 12 and 13 each have a disk-shaped cover body 121 and a cover body 131. The cover body 121 and the cover body 131 each have annular partition walls 122 and 132 that extend continuously inward in the axial direction CL from the cover body 121 and the cover body 131, respectively, so as to face each other when the motor 1 is fully assembled. The partition walls 122 and 132 each have annular grooves 122a and 132a on their outer peripheral surfaces on the radially outward side (in a direction perpendicular to the axial direction CL).

[0023] The grooves 122a and 132a respectively accommodate the annular sealing members 14 and 15. The annular sealing members 14 and 15 are, for example, so-called O-rings.

[0024] The stator 20 includes a stator core 21 and a plurality of coils 22 inserted into slots in the stator core 21. The coils 22 are exposed from the stator core 21 at each end in the axial direction CL of the stator core 21. These exposed portions of the coils 22 are called "coil ends." The coils 22 are electrically connected to an inverter (not shown), and the stator 20 is configured to generate a rotating magnetic field by controlling the current flowing through the coils 22.

[0025] The rotor 30 is supported by the shaft 50 and is arranged to rotate relative to the stator 20 with a predetermined gap provided inside the stator 20. The rotor 30 includes a plurality of permanent magnets (not shown) embedded therein. The rotor 30 rotates in synchronization with the rotating magnetic field generated by the stator 20. The motor 1 is a so-called embedded permanent magnet synchronous motor.

[0026] The insulating sealing member 40 is made of resin and has a cylindrical shape. The insulating sealing member 40 may be made of carbon fiber. The resin constituting the insulating sealing member 40 may be a fiber-reinforced resin or a combination of multiple resin materials. The insulating sealing member 40 is disposed on the outer peripheral surfaces of the partition walls 122 and 132 of the covers 12 and 13 of the housing 10, via the annular sealing members 14 and 15. That is, as shown in FIGS. 1 and 2 , the partition walls 122 and the annular sealing member 14 are located radially inward of the insulating sealing member 40 and function as support portions for the reinforcing portion 42 of the insulating sealing member 40, and the partition walls 132 and the annular sealing member 15 are located radially inward of the insulating sealing member 40 and function as support portions for the reinforcing portion 43 of the insulating sealing member 40. As a result, a stator chamber 100 that houses the stator 20 and a rotor chamber 200 that is separated from the stator chamber 100 and houses the rotor 30 are formed within the housing 10. The interior of the stator chamber 100 is filled with a coolant W, such as oil, that cools the coil ends of the coils 22. The insulating sealing member 40 holds the stator chamber 100 so that it is liquid-tight with the coolant W.

[0027] As shown in FIG. 2 , the insulating sealing member 40 has a rotor-facing portion 41 , a reinforcing portion 42 , and a reinforcing portion 43 .

[0028] The rotor facing portion 41 faces the rotor 30 in the radial direction when the motor 1 is fully assembled. The rotor facing portion 41 has a thickness that is relatively smaller than the reinforcing portions 42 and 43. This allows the gap G between the stator core 21 of the stator 20 and the rotor 30 to be reduced, which contributes to improving the torque performance of the motor 1.

[0029] The reinforcing portion 42 is provided at one end in the axial direction CL (the tip end side in the insertion direction A). The reinforcing portion 42 is provided continuously from the rotor facing portion 41 and extends toward the tip end side. The reinforcing portion 42 has a thickness t1 that is greater than the thickness of the rotor facing portion 41. The thickness t1 is greater than the gap G between the stator core 21 of the stator 20 and the rotor 30. The reinforcing portion 42 is formed thicker radially inward from the rotor facing portion 41. Furthermore, the reinforcing portion 42 faces one coil end (the tip end side) of the coil 22 when the motor 1 is fully assembled.

[0030] The reinforcing portion 43 is provided at the other end in the axial direction CL (rear end side in the insertion direction A). The reinforcing portion 43 extends continuously from the rotor facing portion 41 toward the rear end. The reinforcing portion 43 has a thickness t2 that is greater than the thickness of the rotor facing portion 41. The thickness t2 is greater than the gap G between the stator core 21 of the stator 20 and the rotor 30. The reinforcing portion 43 is formed to be thicker radially outward from the rotor facing portion 41. As described above, the reinforcing portion 42 is formed to be thicker radially inward from the rotor facing portion 41. Therefore, the outer peripheral surface of the partition wall 132 of the cover 13 is formed to be positioned radially outward from the outer peripheral surface of the partition wall 122 of the cover 12. In other words, the reinforcing portion 42 is supported by the partition wall 122 of the housing 10 radially inward of the reinforcing portion 43. Furthermore, the reinforcing portion 43 faces the other (rear end) coil end of the coil 22 when the motor 1 is fully assembled.

[0031] In this way, reinforcing portions 42 and 43 are formed to be thicker than rotor-facing portion 41, thereby reinforcing insulating sealing member 40. Furthermore, by arranging reinforcing portions 42 and 43 facing the coil ends, motor 1 can be made smaller in the axial direction, and further, insulation between the coil ends and partition walls 122 and 132 of housing 10 can be sufficiently ensured.

[0032] Furthermore, by forming the reinforcing portion 42 to be thicker radially inward and the reinforcing portion 43 located at the rear end side in the insertion direction A to be thicker radially outward, the rotor 30 can be easily inserted radially closer to the insulating sealing member 40, and the gap G between the stator core 21 of the stator 20 and the rotor 30 can be made smaller, thereby achieving a radially smaller motor 1. Furthermore, by supporting the reinforcing portion 42 radially inward of the reinforcing portion 43 on the partition wall 122 of the housing 10, the internal space of the housing 10 can be used more effectively, and the space savings allow a radially smaller motor 1.

[0033] At least one of the reinforcing portion 42 and the reinforcing portion 43 has a chamfered portion 421 and a chamfered portion 431 on the outer side in the axial direction CL, i.e., on the radially inner end located opposite the end on the rotor-facing portion 41 side. By forming the chamfered portion 421 on the reinforcing portion 42, when the insulating sealing member 40 is inserted and the end of the reinforcing portion 42 abuts against the end of the partition wall 122 of the housing 10, the chamfered portion 421 functions as a guide, allowing the reinforcing portion 42 to be smoothly inserted along the outer peripheral surface of the partition wall 122 and supported thereon. In addition, it is possible to prevent the reinforcing portion 42 from getting caught in the annular sealing member 14 disposed in the groove 122a of the partition wall 122. Furthermore, by forming the chamfered portion 431 on the reinforcing portion 43, when attaching the cover 13 after inserting the insulating sealing member 40, the chamfered portion 431 functions as a guide, allowing the partition wall 132 of the cover 13 to be smoothly inserted and supported along the inner circumferential surface of the reinforcing portion 43 of the insulating sealing member 40. Furthermore, it is possible to prevent the reinforcing portion 43 from getting caught in the annular sealing member 15 placed in the groove portion 132a of the partition wall 132.

[0034] The reinforcing portion 42 abuts against the cover 12 of the housing 10 in the axial direction CL. In this embodiment, the reinforcing portion 42 abuts against a step 122b formed on the partition wall 122 of the cover 12. The step 122b is formed so as to expand radially outward from the outer peripheral surface of the partition wall 122 that faces the reinforcing portion 42. In this way, the reinforcing portion 42 abuts against the housing 10 in the axial direction CL, making it possible to easily position the insulating sealing member 40 when inserting it.

[0035] At least one of the ends of the reinforcing portion 42 and the reinforcing portion 43, i.e., the ends of the reinforcing portion 42 and the reinforcing portion 43 opposite the rotor-facing portion 41, is positioned outward in the axial direction CL with respect to the coil end of the coil 22, as shown by arrows B and C in Figure 2. More specifically, the end of the reinforcing portion 42 is positioned further forward in the insertion direction A than the coil end in the axial direction CL. The end of the reinforcing portion 43 is positioned further rearward in the insertion direction A than the coil end in the axial direction CL. This more reliably ensures insulation between the coil end of the coil 22 and the partition walls 122 and 132 of the housing 10.

[0036] 3, the insulating sealing member 40 may have reinforcing portions 42 and 43 that are thicker radially inward relative to the rotor-facing portion 41, and the thickness t2 of the reinforcing portion 43 may be smaller than the thickness t1 of the reinforcing portion 42. This makes it easier to insert the rotor 30 into the housing after inserting the insulating sealing member 40, and also makes it possible to reduce the gap G, compared to when the thicknesses t1 and t2 are the same.

[0037] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention.

[0038] 1: motor, 10: housing, 11: housing body, 12: cover, 121: cover body, 122: partition wall, 122a: groove portion, 122b: step portion, 13: cover, 131: cover body, 132: partition wall, 132a: groove portion, 14: annular sealing member, 15: annular sealing member, 20: stator, 21: stator core, 22: coil, 30: rotor, 40: insulating sealing member, 41: rotor facing portion, 42: reinforcing portion, 421: chamfered portion, 43: reinforcing portion, 431: chamfered portion, 50: shaft, 100: stator chamber, 200: rotor chamber, CL: axial direction, A: insertion direction, G: gap, t1: thickness, t2: thickness, W: coolant

Claims

1. A rotor comprising: a stator; a rotor rotatably provided inside the stator; a housing having a stator chamber that accommodates coil ends of the stator and a cooling liquid for cooling the coil ends such that liquid-tightness is maintained by the cooling liquid, and a rotor chamber that accommodates the rotor; and a cylindrical insulating sealing member that is accommodated in the housing, separates the stator chamber and the rotor chamber, and maintains the stator chamber liquid-tight, the insulating sealing member including a rotor facing portion that faces the rotor, a first reinforcing portion that is provided at one end in the axial direction and has a thickness greater than that of the rotor facing portion, and a second reinforcing portion that is provided at the other end in the axial direction and has a thickness greater than that of the rotor facing portion, the first reinforcing portion and the second reinforcing portion each having a thickness equal to or greater than the gap between the stator and the rotor, the first reinforcing portion and the second reinforcing portion each facing the coil ends of the stator radially outward, The motor, wherein the housing has, radially inward, a first support portion that supports the first reinforcing portion and a second support portion that supports the second reinforcing portion.

2. A motor according to claim 1, wherein the first reinforcing portion is formed to be thicker toward the inside in the radial direction, the second reinforcing portion is formed to be thicker toward the inside in the radial direction, and the second reinforcing portion has a thickness smaller than that of the first reinforcing portion.

3. A motor according to claim 1, wherein the first reinforcing portion is formed so as to become thicker radially inward, and the second reinforcing portion is formed so as to become thicker radially outward.

4. A motor according to any one of claims 1 to 3, wherein either the first reinforcing portion or the second reinforcing portion has a chamfered portion whose radially inner end is chamfered.

5. A motor according to any one of claims 1 to 4, wherein the first reinforcing portion abuts against the housing in the axial direction.

6. A motor according to any one of claims 1 to 5, wherein the first reinforcing portion is supported by the first supporting portion radially inward of the second reinforcing portion.

7. A motor according to any one of claims 1 to 6, wherein an end of either the first reinforcing portion or the second reinforcing portion is positioned axially outward with respect to a coil end of the stator.

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