Motor unit

Abstract

This invention provides a novel structure for attaching the temperature-measuring part of a coil to a temperature sensor. [Solution] The motor unit comprises a case. The motor unit comprises a motor housed in the case and having a coil. The motor unit comprises a motor busbar connected to the coil. The motor unit comprises a first terminal located at the tip of the motor busbar. The motor unit comprises a temperature measuring unit connected to the coil. The motor unit comprises a terminal block fixed to the case. The motor unit comprises a second terminal provided on the terminal block and detachably connected to the first terminal. The motor unit comprises a temperature sensor unit fixed to the terminal block and detachably connected to the temperature measuring unit.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a motor unit.

Background Art

[0002] Patent Document 1 describes a motor unit. In this motor unit, in a cover covering a stator coil, a temperature sensor portion is disposed at a position facing a coil end. Simultaneously with the assembly of the cover, the temperature sensor portion is sandwiched between the inner surface of the cover and the coil end. Thereby, the assembly of the temperature sensor portion is completed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the mode of assembling the temperature sensor simultaneously with the assembly of the cover as in Patent Document 1, the operator's view is blocked by the cover. Therefore, it is difficult to visually confirm the assembly state such as whether there is a positional deviation or damage in the temperature sensor.

Means for Solving the Problems

[0005] The technology disclosed herein is embodied in a motor unit. In a first aspect of this technology, the motor unit comprises a case. The motor unit comprises a motor housed in the case and having a coil. The motor unit comprises a motor busbar connected to the coil. The motor unit comprises a first terminal located at the end of the motor busbar. The motor unit comprises a temperature measuring unit connected to the coil. The motor unit comprises a terminal block fixed to the case. The motor unit comprises a second terminal provided on the terminal block and detachably connected to the first terminal. The motor unit comprises a temperature sensor unit fixed to the terminal block and detachably connected to the temperature measuring unit.

[0006] In the above configuration, the temperature sensor unit is fixed to the terminal block. This allows the temperature sensor unit and the temperature measuring unit to be attached to each other simultaneously when assembling the terminal block into the case. The terminal block is sufficiently small compared to the cover, so it does not obstruct the worker's view. Therefore, the assembly status of the temperature sensor unit and the temperature measuring unit can be visually confirmed. This makes it possible to suppress the occurrence of assembly defects in the temperature sensor unit. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic cross-sectional view of motor unit 1. [Figure 2] This is a front view from the direction of arrow Y2 in Figure 1. [Figure 3] This is a side view from the direction of arrow Y3 in Figure 2. [Figure 4] This is a front view showing the terminal block 40 before assembly. [Figure 5] Figure 2 is a cross-sectional view along the VV line. [Figure 6] This is a cross-sectional view of the temperature sensor section 49 of Example 2. [Modes for carrying out the invention]

[0008] In a second aspect of this technology, in addition to the first aspect described above, the first terminal and the temperature measuring section may protrude along the first direction. The second terminal may extend along the first direction and have a contact surface that contacts the first terminal. The temperature sensor section may further extend along the first direction and have an insertion hole configured to allow insertion and removal of the temperature measuring section.

[0009] With this configuration, the temperature measuring unit can be inserted into the insertion hole when assembling the terminal block into the case. This makes it possible to install the temperature sensor unit and the temperature measuring unit simultaneously with the assembly of the terminal block.

[0010] In a third aspect of this technology, in addition to the fastening members that secure the first terminal and the second terminal as described in the first or second aspect, the technology may further include fastening members that secure the first terminal and the second terminal.

[0011] In a fourth aspect of this technology, in addition to any one of the first to third aspects, the temperature sensor unit may be fixed to the terminal block in a manner that allows it to move along the first direction. A first elastic member may further be provided that biases the temperature sensor unit toward the temperature measuring unit along the first direction.

[0012] This configuration makes it possible to suppress situations where connection problems occur between the temperature measuring unit and the temperature sensor unit.

[0013] In a fifth aspect of this technology, in addition to the fourth aspect described above, the terminal block may include a hole that extends along the first direction and faces the temperature measuring section. The temperature sensor section may be located inside the hole. The terminal block may further include a first seal that surrounds the outer circumferential surface of the temperature sensor section and is located between the outer circumferential surface and the inner circumferential surface of the hole.

[0014] This configuration makes it possible to improve the airtightness of the case.

[0015] In a sixth aspect of the present technology, in addition to the above-described second or third aspect, a second elastic member disposed inside the insertion hole of the temperature sensor unit may be further provided. The second elastic member may bias the temperature measuring unit inserted into the insertion hole along a second direction substantially orthogonal to the first direction.

[0016] According to such a configuration, the urging force of the second elastic member can make it difficult for the temperature measuring unit to come out of the insertion hole.

[0017] In a seventh aspect of the present technology, in addition to the above-described sixth aspect, the terminal block may include a hole portion that extends along the first direction and faces the temperature measuring unit. The temperature sensor unit may be disposed inside the hole portion. A first seal that surrounds the periphery of the outer peripheral surface of the temperature sensor unit and is disposed between the outer peripheral surface and the inner peripheral surface of the hole portion may be further provided.

[0018] According to such a configuration, it is possible to enhance the airtightness of the case.

[0019] In an eighth aspect of the present technology, in addition to the above-described sixth aspect, the terminal block may include a hole portion that extends along the first direction and faces the temperature measuring unit. The temperature sensor unit may be disposed inside the hole portion. A wiring hole through which a wiring drawn from the temperature sensor unit passes may be formed on the bottom surface of the hole portion. A second seal that surrounds the periphery of the wiring hole and is disposed between the bottom surface of the hole portion and the temperature sensor unit may be further provided.

[0020] According to such a configuration, it is possible to enhance the airtightness of the case.

[0021] In a ninth aspect of the present technology, in addition to the second or third aspect described above, the terminal block may include a hole portion that extends along the first direction and faces the temperature measurement portion. The temperature sensor portion may be disposed inside the hole portion. The temperature sensor portion may further include a first seal that surrounds the outer peripheral surface of the temperature sensor portion and is disposed between the outer peripheral surface and the inner peripheral surface of the hole portion.

[0022] According to such a configuration, it is possible to enhance the airtightness of the case.

[0023] In a tenth aspect of the present technology, in addition to the second or third aspect described above, the terminal block may include a hole portion that extends along the first direction and faces the temperature measurement portion. The temperature sensor portion may be disposed inside the hole portion. A wiring hole through which wiring drawn from the temperature sensor portion passes may be formed in the bottom surface of the hole portion. The temperature sensor portion may further include a second seal that surrounds the periphery of the wiring hole and is disposed between the bottom surface of the hole portion and the temperature sensor portion.

[0024] According to such a configuration, it is possible to enhance the airtightness of the case.

[0025] In an eleventh aspect of the present technology, in addition to any one of the first to tenth aspects, the temperature measurement portion may be connected to the neutral point of the coil.

Example

[0026] Figure 1 shows a schematic cross-sectional view of the motor unit 1 according to this embodiment. In Figure 1, the x-direction is the direction in which the central axis CA of the shaft 22 extends. The y and z directions are directions in a plane perpendicular to the central axis CA. The coordinate relationship is the same in subsequent figures. Figure 1 is a cross-sectional view taken along line II in Figure 2. That is, Figure 1 is a cross-sectional view passing through the central axis CA, the first terminal 34a, and the second terminal 44a. Figure 2 shows a front view taken from the direction of arrow Y2 in Figure 1. Figure 3 shows a side view taken from the direction of arrow Y3 in Figure 2. Figure 4 shows a front view of the terminal block 40 before assembly. Figure 4 is a view taken from the same position as in Figure 2. Note that in Figures 2-4, the case body 10A is shown in a cross-sectional view for clarity.

[0027] The motor unit 1 mainly comprises a case 10, a motor 20, a terminal block 40, and an inverter 50. The case 10 consists of a case body 10A and a cover 10B. The motor 20 is housed inside the case body 10A. The cover 10B closes the opening on the -x side of the case body 10A.

[0028] The motor 20 is a three-phase motor. The motor 20 has a shaft 22, a rotor 24, and a stator 26. The shaft 22 extends along the central axis CA of the motor 20. The rotor 24 is generally cylindrical. The rotor 24 is fixed to the shaft 22. The rotor 24 rotates with the shaft 22 about the central axis CA as the center of rotation. The stator 26 is generally cylindrical. The stator 26 has a stator core 28 and coils 30. The coils 30 include a U-phase coil 30U, a V-phase coil 30V, and a W-phase coil 30W. One end 30Ua of the U-phase coil 30U, one end 30Va of the V-phase coil 30V, and one end 30Wa of the W-phase coil 30W protrude from the coils 30 in the -x direction.

[0029] Each of the motor busbars 32, 34, and 36 is a plate-shaped member, formed using a conductive material such as metal. The base end 32b of motor busbar 32 is welded to one end 30Ua. The base end 34b of motor busbar 34 is welded to one end 30Va. The base end 36b of motor busbar 36 is welded to one end 30Wa. Each of the motor busbars 32, 34, and 36 has a flat first terminal 32a, 34a, and 36a located at its tip. The first terminals 32a, 34a, and 36a protrude in the +z direction.

[0030] The temperature sensing element 38 is a rod-shaped or plate-shaped member. The temperature sensing element 38 is a member used to measure the temperature of the coil 30. The temperature sensing element 38 is formed using a conductive material such as metal. The base end 38b of the temperature sensing element 38 is connected to the neutral point (not shown) of the coil 30. The tip 38t of the temperature sensing element 38 protrudes in the +z direction.

[0031] The terminal block 40 is fixed to the case 10. Specifically, the terminal block 40 is fitted into a through hole 10h formed in the case body 10A. The terminal block 40 mainly comprises a base 41, second terminals 42a, 44a, 46a, terminal block busbars 42, 44, 46, and a temperature sensor section 49. The base 41 is made of an insulator, such as a resin material. The second terminals 42a, 44a, 46a are arranged on the base 41. The second terminals 42a, 44a, 46a extend along the z direction and are aligned along the y direction. The second terminals 42a, 44a, 46a are plate-shaped members and are formed using a conductive material such as metal. Each of the second terminals 42a, 44a, 46a has contact surfaces 42s, 44s, 46s. Each of the contact surfaces 42s, 44s, and 46s is a surface that contacts the first terminals 32a, 34a, and 36a, respectively. Each of the second terminals 42a, 44a, and 46a is fixed to each of the first terminals 32a, 34a, and 36a by a bolt 48.

[0032] Terminal block busbars 42, 44, and 46 are connected to each of the second terminals 42a, 44a, and 46a, respectively. In this embodiment, each of the terminal block busbars 42, 44, and 46 is formed integrally with the second terminals 42a, 44a, and 46a. In a modified example, each of the terminal block busbars 42, 44, and 46 may be constructed separately from the second terminals 42a, 44a, and 46a and connected by fastening members. The ends of the terminal block busbars 42, 44, and 46 are connected to a corresponding inverter busbar 52, 54, and 56. In Figures 1-3, each of the inverter busbars 52, 54, and 56 is simply illustrated with a straight line. The inverter busbars 52, 54, and 56 are connected to the inverter 50. The wiring 49w extending from the temperature sensor unit 49 is also connected to the inverter 50.

[0033] (Structure of the temperature sensor unit 49) A temperature sensor unit 49 is fixed to the terminal block 40. The specific details of the temperature sensor unit 49 will be explained below. Figure 5 shows a cross-sectional view of the VV line in Figure 2. Figure 5 is a cross-sectional view passing through the temperature sensor unit 49 and the temperature measuring unit 38.

[0034] The temperature sensor unit 49 mainly comprises a base unit 49A, a sensor element 49s, and wiring 49w. The base unit 49A extends along the z direction. The base unit 49A is made of an insulator, such as a resin material. An insertion hole 49h is opened at the -z end of the base unit 49A. The insertion hole 49h extends along the z direction and is configured to allow insertion and removal of the temperature measuring unit 38. Figure 5 shows the state in which the tip 38t of the temperature measuring unit 38 is inserted into the insertion hole 49h.

[0035] By fixing the terminal block 40 to the through hole 10h, the position of the insertion hole 49h in the xy plane is determined. Similarly, by fixing the stator 26 inside the case body 10A, the position of the tip 38t in the xy plane is determined. The temperature sensor unit 49 is positioned so that the xy plane position of the determined insertion hole 49h and the xy plane position of the determined tip 38t coincide. This makes it possible to attach the temperature sensor unit 49 and the temperature measuring unit 38 to each other simultaneously when assembling the terminal block 40 to the case body 10A, as will be described later.

[0036] A sensor element 49s is positioned near the bottom surface of the insertion hole 49h. Various types of elements can be used for the sensor element 49s. In this embodiment, the sensor element 49s is a thermistor. Wiring 49w is connected to the sensor element 49s. Wiring 49w is drawn out from the bottom surface 49b of the base portion 49A.

[0037] A hole 41h is formed at the -z end of the base 41 of the terminal block 40. The hole 41h extends along the z direction and faces the temperature measuring unit 38. A temperature sensor unit 49 is positioned inside the hole 41h. Specifically, the temperature sensor unit 49 is fitted into the hole 41h in a manner that allows it to slide in the z direction. As a result, the temperature sensor unit 49 is fixed to the terminal block 40 in a manner that allows it to move along the z direction. In addition, a wiring hole 41w is formed in the bottom surface 41b of the hole 41h, penetrating in the z direction. Wiring 49w is routed inside the wiring hole 41w. As a result, the wiring 49w can be pulled out to the outside through the wiring hole 41w.

[0038] A first elastic member 51 is positioned between the bottom surface 41b of the hole 41h and the bottom surface 49b of the temperature sensor part 49. Various types of materials can be used for the first elastic member 51. In this embodiment, the first elastic member 51 is a helical spring. The first elastic member 51 biases the temperature sensor part 49 toward the temperature measuring part 38 along the z direction. This maintains the state in which the tip 38t of the temperature measuring part 38 is inserted all the way into the insertion hole 49h. This makes it possible to suppress situations in which connection failures occur between the temperature measuring part 38 and the temperature sensor part 49.

[0039] A first seal 61 is positioned between the outer circumferential surface 49o of the temperature sensor portion 49 and the inner circumferential surface 41i of the hole portion 41h. The first seal 61 surrounds the outer circumferential surface 49o. The first seal 61 can seal the inside and outside of the case 10, thereby improving the airtightness of the case 10. The material and type of the first seal 61 can vary. In this embodiment, the first seal 61 is a resin O-ring.

[0040] (Assembly process and effects) The assembly process for the terminal block 40 will now be explained. Prepare the case body 10A in a state where it is not blocked by the cover 10B. Assemble the stator 26 inside the case body 10A. This positions the x and y plane position of the tip 38t of the temperature sensing unit 38.

[0041] Next, as shown in Figure 4, the terminal block 40 is assembled to the case body 10A. Specifically, the terminal block 40 is inserted into the through hole 10h of the case body 10A (see arrow AD). This allows the insertion hole 49h to be positioned in the xy plane and moved closer to the tip 38t. As mentioned above, the temperature sensor unit 49 is fixed to the terminal block 40 such that the xy plane position of the insertion hole 49h and the xy plane position of the tip 38t coincide. Therefore, by inserting the terminal block 40 into the through hole 10h, the tip 38t can be inserted into the insertion hole 49h (see Figure 2). In other words, when assembling the terminal block 40 to the case body 10A, the temperature sensor unit 49 and the temperature measuring unit 38 can be attached to each other at the same time.

[0042] Next, bolts 48 are used to secure the second terminals 42a, 44a, and 46a to the first terminals 32a, 34a, and 36a, respectively. Terminal busbars 42, 44, and 46 are then connected to inverter busbars 52, 54, and 56, respectively. The cover 10B is then attached to the case body 10A using fastening members (not shown). This completes the assembly process of the terminal block 40.

[0043] Let me explain the effect. The terminal block 40 is sufficiently small compared to the cover 10B, so it does not obstruct the worker's view. Therefore, the temperature sensor unit 49 and the temperature measuring unit 38 can be assembled while visually checking from the side of arrow Y2 in Figure 1. In other words, it becomes possible to visually confirm whether or not the tip 38t has been inserted into the insertion hole 49h. This makes it possible to suppress the occurrence of assembly defects of the temperature sensor unit 49. [Examples]

[0044] In Example 2, the elastic member of the temperature sensor unit 49 differs from that in Example 1. Parts common to both Example 1 and Example 2 are given the same reference numerals, and their descriptions are omitted. Figure 6 shows a cross-sectional view of the temperature sensor unit 49 in Example 2. Figure 6 of Example 2 is a cross-sectional view taken at the same position as Figure 5 of Example 1.

[0045] The temperature sensor unit 49 of Embodiment 2 further comprises a second elastic member 72. The second elastic member 72 is located inside the insertion hole 49h. The second elastic member 72 is positioned on the +x direction side with respect to the insertion hole 49h. The sensor element 49s is positioned on the -x direction side with respect to the insertion hole 49h. That is, the second elastic member 72 and the sensor element 49s are positioned opposite each other in the x direction. The second elastic member 72 biases the temperature measuring unit 38, which is inserted into the insertion hole 49h, in direction D1. In other words, the second elastic member 72 biases the temperature measuring unit 38 in a direction (-x direction) that is substantially perpendicular to the insertion direction (z direction). As a result, the temperature measuring unit 38 is in close contact with the inner wall of the insertion hole 49h on the -x direction side. The inner wall on the -x direction side is the part where the sensor element 49s is located. Therefore, the temperature measuring unit 38 can maintain a state in close proximity to the sensor element 49s. This makes it possible to suppress situations in which connection failures occur between the temperature measuring unit 38 and the temperature sensor unit 49. In addition, the biasing force of the second elastic member 72 makes it difficult for the temperature measuring unit 38 to come out of the insertion hole 49h.

[0046] Various types of materials can be used for the second elastic member 72. In this embodiment, the second elastic member 72 is a leaf spring.

[0047] A second seal 62 is positioned between the bottom surface 41b of the hole 41h and the bottom surface 49b of the temperature sensor 49. The second seal 62 surrounds the wiring hole 41w. The second seal 62 can seal the wiring hole 41w, thereby improving the airtightness of the case 10. The material and type of the second seal 62 may vary. In this embodiment, the second seal 62 is a resin O-ring.

[0048] In Example 2, a configuration comprising both the first seal 61 and the second seal 62 was described, but the invention is not limited to this configuration. A configuration comprising at least one of the first seal 61 and the second seal 62 is also acceptable. This makes it possible to maintain the airtightness of the case 10.

[0049] The specific examples of the technology disclosed herein have been described in detail above, but these are merely illustrative and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples described above. The technical elements described herein or in the drawings exhibit technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology illustrated herein or in the drawings achieves multiple objectives simultaneously, and achieving even one of these objectives itself constitutes technical usefulness.

[0050] (modified version) The base end 38b of the temperature sensing element 38 is not limited to the neutral point, but can be connected to various other locations. Furthermore, the manner in which the base end 38b is connected to the coil can vary. For example, it may be connected by welding or fastening to an arc-shaped busbar connecting the ends of the coil wires. Alternatively, the temperature sensing element 38 may be formed integrally with the coil wire. [Explanation of symbols]

[0051] 1: Motor unit 10: Case 20: Motor 30: Coil 32, 34, 36: Motor busbar 32a, 34a, 36a: First terminal 40: Terminal block 42a, 44a, 46a: Second terminal 49: Temperature sensor unit

Claims

1. A motor unit, The case and A motor housed in the aforementioned case and having a coil, A motor busbar connected to the aforementioned coil, The first terminal located at the tip of the motor busbar, A temperature measuring unit connected to the coil, The terminal block fixed to the aforementioned case, A second terminal is provided on the terminal block and is detachably connected to the first terminal, A temperature sensor unit is fixed to the terminal block and is detachably connected to the temperature measuring unit, A motor unit equipped with the following features.

2. The first terminal and the temperature measuring section protrude along the first direction, The second terminal extends along the first direction and has a contact surface that is in contact with the first terminal. The motor unit according to claim 1, wherein the temperature sensor portion extends along the first direction and further comprises an insertion hole configured to allow insertion and removal of the temperature measuring portion.

3. The motor unit according to claim 2, further comprising a fastening member that fixes the first terminal and the second terminal.

4. The temperature sensor unit is fixed to the terminal block in a manner that allows it to move along the first direction. The motor unit according to any one of claims 1 to 3, further comprising a first elastic member that biases the temperature sensor portion toward the temperature measuring portion along the first direction.

5. The terminal block has a hole that extends along the first direction and faces the temperature measuring section, The temperature sensor unit is located inside the hole. The motor unit according to claim 4, further comprising a first seal surrounding the outer circumferential surface of the temperature sensor portion, the first seal being disposed between the outer circumferential surface and the inner circumferential surface of the hole portion.

6. The motor unit according to claim 2 or 3, further comprising a second elastic member disposed inside the insertion hole of the temperature sensor portion, the second elastic member biasing the temperature measuring portion inserted into the insertion hole along a second direction substantially perpendicular to the first direction.

7. The terminal block has a hole that extends along the first direction and faces the temperature measuring section, The temperature sensor unit is located inside the hole. The motor unit according to claim 6, further comprising a first seal surrounding the outer circumferential surface of the temperature sensor portion, the first seal being disposed between the outer circumferential surface and the inner circumferential surface of the hole portion.

8. The terminal block has a hole that extends along the first direction and faces the temperature measuring section, The temperature sensor unit is located inside the hole. A wiring hole is formed in the bottom surface of the aforementioned hole for the wiring coming out from the temperature sensor to pass through. The motor unit according to claim 6, further comprising a second seal surrounding the wiring hole, the second seal being positioned between the bottom surface of the hole and the temperature sensor portion.

9. The terminal block has a hole that extends along the first direction and faces the temperature measuring section, The temperature sensor unit is located inside the hole. The motor unit according to claim 2, further comprising a first seal surrounding the outer circumferential surface of the temperature sensor portion, the first seal being disposed between the outer circumferential surface and the inner circumferential surface of the hole portion.

10. The terminal block has a hole that extends along the first direction and faces the temperature measuring section, The temperature sensor unit is located inside the hole. A wiring hole is formed in the bottom surface of the aforementioned hole for the wiring coming out from the temperature sensor to pass through. The motor unit according to claim 2, further comprising a second seal surrounding the wiring hole, the second seal being disposed between the bottom surface of the hole and the temperature sensor portion.

11. The motor unit according to claim 1, wherein the temperature measuring unit is connected to the neutral point of the coil.

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