Motor

Abstract

To provide a structure for simplifying a process to fit a spring which presses a temperature sensor against a coil in a motor.SOLUTION: A motor comprises: a coil wound around a stator; a bus bar connected to the coil; a temperature sensor which is in contact with the coil; a spring which presses the temperature sensor against the coil. The bus bar is disposed so as to face the coil. The temperature sensor is disposed between the coil and the bus bar. The spring is disposed between the bus bar and the temperature sensor. With this structure, the bus bar and the spring can be fitted to the coil at the same time. Thus, this structure can simplify a process to fit the spring which presses the temperature sensor against the coil.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] When the motor has a large output, the stator coil generates heat. In order to measure the temperature of the stator or coil, a temperature sensor is attached to the stator or coil of the motor. Patent documents 1-4 disclose examples of motors with a temperature sensor attached to the stator or coil. In the motor of Patent document 1, a temperature sensor is attached to a conductor extending from the coil. In the motor of Patent document 2, a temperature sensor is attached to the coil. In the motor of Patent document 3, a temperature sensor is attached to a bus bar connected to the coil. The temperature sensor is disposed between the bus bar and a cover (a cover that covers the end of the motor housing). A biasing member is disposed between the temperature sensor and the cover. The biasing member presses the temperature sensor against the bus bar. In the motor of Patent document 4, the temperature sensor is attached to the coil. The temperature sensor is disposed between the inner surface of the motor housing and the coil, and an elastic member is disposed between the temperature sensor and the inner surface of the housing. The elastic member presses the temperature sensor against the coil. The elastic member presses the temperature sensor against the coil, so that the temperature sensor comes into close contact with the coil, and the temperature of the coil is accurately measured. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-99177 A [Patent Document 2] U.S. Patent Publication No. 2021 / 0278284 [Patent Document 3] JP 2023-89815 A [Patent Document 4] International Publication No. 2011 / 117985 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a structure that simplifies the process of attaching the spring that presses the temperature sensor against the coil. [Means for solving the problem]

[0005] The motor disclosed in this specification includes a coil wound around a stator, a bus bar connected to the coil, a temperature sensor in contact with the coil, and a spring that presses the temperature sensor against the coil. The bus bar is disposed so as to face the coil. The temperature sensor is disposed between the coil and the bus bar. Note that "in contact with the coil" means that the temperature sensor is thermally in contact with the coil. That is, a heat-conductive adhesive layer may be interposed between the coil and the temperature sensor. The spring is disposed between the bus bar and the temperature sensor. According to this structure, the bus bar and the spring can be attached to the coil at the same time. That is, according to this structure, the attachment process of the spring that presses the temperature sensor against the coil can be simplified. Note that if the spring is fixed to the bus bar, the spring can be moved together with the bus bar. The spring can also be attached by an automated device that handles the bus bar and fixes it to the stator.

[0006] Details and further improvements of the technology disclosed in this specification are described in the following "Forms for Carrying Out the Invention". [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic structural diagram of a motor according to a first embodiment. [Diagram 2] 2 is a view of the dashed-line area II in FIG. 1 as viewed from the direction of arrow A. [Diagram 3] FIG. 11 is a diagram showing the periphery of a temperature sensor of a motor according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] (First embodiment) Fig. 1 shows a schematic cross-sectional view of a motor 2 of a first embodiment. Although Fig. 1 is a cross-sectional view, the hatching that represents the cross section has been omitted. The motor 2 comprises a stator 3, a rotor 4, and a housing 5 that accommodates them. The stator 3 is fixed to the inner surface of the housing 5. The structure of the portion to which the stator 3 is fixed has been omitted from the illustration. The rotor 4 is supported by the housing 5 via a bearing.

[0009] A coil 10 is wound around the stator 3. In Fig. 1 and Fig. 2, the individual windings of the coil 10 are omitted, and only the outline of the coil 10 is shown. A temperature sensor 20 is attached to the end of the coil 10. Fig. 2 is a view of the dashed line area II in Fig. 1 as seen from the direction of arrow A. The attachment structure of the temperature sensor 20 will be explained with reference to Fig. 2. Note that the signal wire of the temperature sensor 20 is omitted from the illustration.

[0010] The temperature sensor 20 is provided to measure the temperature of the coil 10. The temperature sensor 20 is, for example, a thermistor. The temperature sensor 20 is attached to the coil 10 via an adhesive resin 21. The adhesive resin is, for example, a varnish or an adhesive sheet. The temperature sensor 20 may be attached to the coil 10 without the adhesive resin.

[0011] Meanwhile, a busbar unit 30 is located above the temperature sensor 20. The busbar unit 30 includes a relay busbar 31 that connects the coil 10 and the external busbar 40, and a resin block 32 that supports the relay busbar 31. A part of the relay busbar 31 is embedded in the resin block 32. In FIG. 2, the resin block 32 and a bolt that fixes the resin block 32 are drawn by an imaginary line. In FIG. 1, the resin block 32 is shown by an imaginary line, and the bolt is omitted. The busbar unit 30 is fixed to the stator 3 by a bolt. One end of the relay busbar 31 is connected to the lead wire 12 of the coil 10, and the other end of the relay busbar 31 is connected to the external busbar 40. The relay busbar 31 and the lead wire 12 are connected by welding. The relay busbar 31 may be connected to the lead wire 12 by a bolt.

[0012] The relay bus bar 31 extends to the outside of the housing 5 through a hole 6 provided in the housing 5. One end of the relay bus bar 31 reaches a terminal block 41 provided on the outer periphery of the housing 5. At the terminal block 41, the relay bus bar 31 and the external bus bar 40 are fastened together with a bolt 42. The external bus bar 40 is connected to an AC output terminal of an inverter (not shown). Power is supplied to the coil 10 from the inverter (not shown) through the external bus bar 40 and the relay bus bar 31.

[0013] As described above, a portion of relay bus bar 31 is embedded in resin block 32, and resin block 32 is fixed to stator 3. A portion of relay bus bar 31 is positioned so as to face coil 10. Temperature sensor 20 is positioned between coil 10 and relay bus bar 31. One end of spring 35 is embedded in resin block 32, and the other end of spring 35 is in contact with temperature sensor 20. Spring 35 is positioned between temperature sensor 20 and relay bus bar 31, and spring 35 presses temperature sensor 20 against coil 10.

[0014] The reaction force of spring 35 caused by pressing temperature sensor 20 is supported by relay bus bar 31. With relay bus bar 31 supporting the reaction force of spring 35, temperature sensor 20 comes into close contact with coil 10. Also, since spring 35 is fixed to bus bar unit 30, spring 35 can be attached at the same time as bus bar unit 30 is attached to stator 3. This simplifies the attachment process of spring 35. More precisely, spring 35 is fixed to resin block 32 of bus bar unit 30.

[0015] (Second embodiment) A motor 102 of a second embodiment will be described with reference to FIG. 3. FIG. 3 is a view of the motor 102 as seen from the direction of the arrow A in FIG. 1, as in FIG. 2. The motor 102 is a three-phase AC electric motor, and a plurality of coils 10u, 10v are wound around the stator 3. In FIG. 3, the individual windings of the coils are also omitted, and only the outer shapes of the coils are shown. The coil 10u is a U-phase coil, and the coil 10v is a V-phase coil. Although not shown in FIG. 3, the stator 3 is also provided with a W-phase coil. As is well known, one ends of the three coils are connected to each other at a neutral point. In FIG. 3, the housing is not shown.

[0016] In the motor 102, a neutral point bus bar 131 connects the coil 10u and the coil 10v. More specifically, one end of the neutral point bus bar 131 is connected to the lead wire 12u of the coil 10u, and the other end is connected to the lead wire 12v of the coil 10v. The neutral point bus bar 131 has a U-shape, and the bottom side of the U faces the coil 10u. A temperature sensor 20 is attached to the coil 10u. The temperature sensor 20 is fixed to the coil 10u with an adhesive resin 21. The temperature sensor 20 is located between the bottom side of the U-shape of the neutral point bus bar 131 and the coil 10u. A spring 35 is disposed between the neutral point bus bar 131 and the temperature sensor 20. The spring 35 is fixed to the neutral point bus bar 131 with an adhesive resin 133, and the spring 35 presses the temperature sensor 20 against the coil 10u. The neutral point bus bar 131 and the adhesive resin 133 are collectively referred to as a bus bar unit 130. The spring 35 is fixed to the neutral point bus bar 131 (bus bar unit 130).

[0017] The reaction force of the spring 35 caused by pressing the temperature sensor 20 is supported by the neutral point bus bar 131. As the neutral point bus bar 131 supports the reaction force of the spring 35, the temperature sensor 20 is in close contact with the coil 10u. In addition, as the spring 35 is fixed to the neutral point bus bar 131 (bus bar unit 130), the spring 35 can be attached at the same time as the neutral point bus bar 131 is attached to the coil 10u (stator 3). This simplifies the attachment process of the spring 35.

[0018] The neutral point bus bar 131 is connected to the leads 12u and 12v by welding. The neutral point bus bar 131 may be connected to the leads 12u and 12v by bolts. The neutral point bus bar 131 may be supported by the stator 3.

[0019] As described above, the spring 35 that presses the temperature sensor 20 against the coil is fixed to the bus bar 31 (131). With this structure, the spring 35 can be attached at the same time as the bus bar 31 (131) is attached. In other words, the process of attaching the spring 35 is simplified.

[0020] The features of the motor 2 (102) of the embodiment are listed below. The motor 2 (102) includes a coil 10 (10u) wound around a stator, bus bars (relay bus bar 31, neutral point bus bar 131) connected to the coil 10 (10u), a temperature sensor 20 in contact with the coil 10 (10u), and a spring 35. The bus bars (relay bus bar 31, neutral point bus bar 131) are arranged to face the coil 10 (10u). The temperature sensor 20 is arranged between the coil 10 (10u) and the bus bars (relay bus bar 31, neutral point bus bar 131). The spring 35 is arranged between the bus bars (relay bus bar 31, neutral point bus bar 131) and the temperature sensor 20, and presses the temperature sensor 20 against the coil 10 (10u).

[0021] In the motor 102, the coils include a first coil (coil 10u) and a second coil (coil 10v). One end of a neutral bus bar 131 is connected to the first coil (coil 10u), and the other end is connected to the second coil (coil 10v). The lead wire 12u of the first coil and the lead wire 12v of the second coil are positioned so as to sandwich the temperature sensor 20. The neutral bus bar 131 connecting the lead wires 12u and 12v is U-shaped, and the lower side of the U faces the temperature sensor 20.

[0022] The spring 35 is fixed to the bus bars (relay bus bar 31, neutral point bus bar 131). More specifically, a portion of the relay bus bar 31 is embedded in the resin block 32, and a portion of the spring 35 is embedded in the resin block 32. In other words, the spring 35 is fixed to the bus bar unit 30 (130). When the spring 35 is fixed to the bus bar unit 30 (130), the spring 35 is also fixed to a predetermined position during the process of handling the bus bar unit 30 (130) and fixing it to the stator 3.

[0023] Points to note regarding the technology described in the embodiment are described below. The temperature sensor 20 is attached to the outer surface of the coil 10 (10u) in the radial direction of the motor 2 (102). The temperature sensor 20 may also be attached to the end surface of the coil 10 (10u) in the axial direction of the motor. The temperature sensor 20 may be attached anywhere on the coil. For example, the temperature sensor may be attached across the first coil and the second coil. In this case, adhesive resin may also be filled between the first coil and the second coil to fill the gap between the two coils.

[0024] One end of the bus bar (relay bus bar 31, neutral bus bar 131) is connected to the lead wire 12 (12u) of the coil 10 (10u). The other end of the bus bar (relay bus bar 31) may be connected to another bus bar (external bus bar 40) or may be connected to the lead wire 12v of another coil 10v.

[0025] The motor 102 of the second embodiment may have a structure in which the neutral bus bar 131 is supported by a resin block, and the resin block is fixed to the stator.

[0026] Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0027] 2, 102: Motor 3: Stator 4: Rotor 5: Housing 6: Hole 10, 10u, 10v: Coil 12, 12u, 12v: Lead wire 20: Temperature sensor 21, 133: Adhesive resin 30, 130: Busbar unit 31: Intermediate busbar 32: Resin block 35: Spring 40: External busbar 41: Terminal block 42: Bolt 131: Neutral busbar

Claims

1. A coil wound around a stator; a bus bar disposed opposite the coil and connected to the coil; a temperature sensor disposed between the coil and the bus bar and in contact with the coil; a spring disposed between the bus bar and the temperature sensor and pressing the temperature sensor against the coil; The motor is provided with:

2. The coil includes a first coil and a second coil, The motor according to claim 1 , wherein one end of the bus bar is connected to the first coil and the other end is connected to the second coil.

3. The motor according to claim 2 , wherein a lead wire of the first coil and a lead wire of the second coil are positioned so as to sandwich the temperature sensor.

4. The motor according to claim 1 , wherein the spring is fixed to the bus bar.

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