TEMPERATURE SENSOR AND ROTATING ELECTRIC MACHINE

Abstract

Temperature sensor (2) for detecting a temperature of a coil (11) provided in a stator (10) of a rotating electrical machine (1), the temperature sensor (2) comprising: a sensor element (20) having a thermosensitive body (211), an electric wire (213, 22) electrically connected to the thermosensitive body (211), and a cover body (24) made of a resin material having elasticity and covering a part of the electric wire and the thermosensitive body (211); and a holder (30) having a rotation axis, which is designed to hold the cover body (24) in a cantilevered manner, wherein the cover body (24) has a first portion (24A) which is at a relatively short distance from the rotation axis (A) and is held by the holder (30), and a second portion (24B) which is at a relatively large distance from the rotation axis (A) and covers the thermosensitive body (211), the second section (24B) is located outside a virtual circle (VC) which passes through the first section (24A) and has the axis of rotation (A) as its center, wherein the cover body (24) is designed to be pressed against the coil (11) by a rotational operation of the cover body (24) in the same direction as a direction of rotational operation of the holder (30) from outside to inside in the radial direction (D3) of the coil (11).

Description

Technical area

[0001] The present invention relates to a temperature sensor and a rotating electrical machine comprising the temperature sensor. background

[0002] In a rotating electrical machine such as an electric motor installed in a vehicle, the temperature of a coil provided in a stator rises when a current flows through the coil. To prevent an excessive temperature rise of the coil and ensure stable operation of the rotating electrical machine, the temperature of the coil is detected by a temperature sensor, and the operation of the rotating electrical machine is controlled based on the detected temperature.

[0003] JP 2010-252508 A proposes that, in a stator of a rotating electrical machine mounted on a vehicle, a temperature sensor is inserted between coils wound around teeth adjacent to each other in a circumferential direction to detect a temperature of the coils. The temperature sensor disclosed in JP 2010-252508 A is coated with an insulating resin layer and held by a holder made of an elastic material such as fluororubber. When the temperature sensor is inserted into a gap between the coils while the holder is elastically deformed, a temperature detection portion of the temperature sensor comes into contact with the coils through the resin layer.

[0004] Document WO 2022 / 130577 A1 is known. It describes a temperature sensor that can be prevented from shifting its position relative to a coil and from detaching from the coil, as well as a rotating electrical machine equipped with the temperature sensor.

[0005] Furthermore, DE 10 2019 124 035 A1 relates to a sensor attachment for temperature measurement in an electrical machine for driving a motor vehicle. Description of the inventionTechnical task

[0006] Even in an environment where vibration occurs, such as in a vehicle, it is desirable to prevent the temperature sensor from deviating from a predetermined position of the coil.

[0007] An object of the present invention is to provide a temperature sensor that can be prevented from deviating from a predetermined position of a coil by an external force such as vibration, and to provide a rotating electric machine having the temperature sensor. Solution to the task

[0008] According to the present invention, a temperature sensor for detecting a temperature of a coil provided in a stator of a rotating electrical machine has the features according to claim 1.

[0009] A rotating electric machine according to the present invention comprises: a stator having a core and a coil; a rotor configured to be rotated with respect to the stator; and the temperature sensor described above. Advantageous effects of the invention

[0010] With the temperature sensor of the present invention, the holder holding the cover body can be attached to the fixation object in a state where the cover body covering the thermosensitive body is elastically deformed and pressed against the coil. Thus, with the temperature sensor of the present invention, it is possible to prevent the sensor element from deviating from the predetermined position of the coil due to an external force such as vibration or impact. As a result, the temperature can be detected stably and accurately. Short character description [ Fig. 1] Fig. 1 is a perspective view illustrating a part of a rotating electric machine according to an embodiment of the present invention. [ Fig. 2] Fig. 2 is a plan view showing a temperature sensor and a coil of Fig. 1 from above. [ Fig. 3A and Fig. 3B] Fig. 3A is a perspective view showing a bracket for attaching a sensor element to the Fig. 1 rotating electrical machine, and Fig. Figure 3B is a top view of the sensor element. [ Fig. 4A and Fig. 4B] Fig. 4A is a plan view illustrating a first position of the bracket before attaching the bracket to a fixation object, and Fig. Figure 4B is a plan view showing a second position of the bracket after attachment. [ Fig. 5] Fig. 5 is a schematic plan view of a temperature sensor according to a first modification. [ Fig. 6A to 6C] Fig. 6A is a schematic cross-sectional view of the temperature sensor according to the embodiment, Fig. 6B is a schematic cross-sectional view of a temperature sensor according to a second modification, and Fig. 6C is a schematic cross-sectional view of a temperature sensor according to a third modification. Description of the embodiment

[0011] An embodiment of the present invention will be described below with reference to the accompanying drawings. [Complete configuration]

[0012] One in Fig. The temperature sensor 2 shown in FIG. 1 is attached to a stator 10 of a rotating electrical machine 1, such as an electric motor and a generator, and detects a temperature of a coil 11 of the stator 10. The rotating electrical machine 1 is installed in a vehicle, such as an electric vehicle. The rotating electrical machine 1 includes a stator 10, a rotor (not shown) rotating around the stator 10, and the temperature sensor 2.

[0013] The stator 10 includes an unillustrated core (hereinafter referred to as the stator core), which is a stacked body of a plurality of electromagnetic steel plates, a substantially cylindrical casing 12 that houses the stator core, and the coil 11 wound around the stator core. The coil 11 is formed of coil wires C wound in a predetermined manner. The coil wires C protrude from a front surface 12A of the casing 12 in an axial direction D1 of the stator 10 to form a coil end 11E.

[0014] In the present embodiment, a distributed winding coil is used as the coil 11; however, the coil 11 is not limited thereto and may be a concentrated winding coil.

[0015] As in Fig. 1 and Fig. 2, the temperature sensor is pressed against the coil end 11E from an outer circumference in a substantially radial direction D3 of the coil 11 to an inner circumference of the stator 10.

[0016] In Fig. 1 and Fig. 2 shows the axial direction D1, a circumferential direction D2, and the radial direction D3 of the stator 10. The radial direction D3 represents a radial direction.

[0017] Further, with the front surface 12A of the housing 12 as a reference, a side where the coil end 11E protrudes in the axial direction D1 is referred to as an “upper side”, and a side opposite thereto is referred to as a “lower side”. [Temperature sensor configuration]

[0018] A configuration of the temperature sensor 2 will be described mainly with reference to Fig. 3A and Fig. 3B. The temperature sensor 2 includes a sensor element 20 that detects a temperature, and a holder 30 that holds the sensor element 20 and is fixed to the housing 12 as a fixing object with a screw 35 as a male screw element. The screw 35 corresponds to a screw that fixes the stator core to the housing 12. As shown in Fig. 4A and Fig. 4B, if necessary, a washer 36 is fixed between a head portion 35A of the screw 35 and a fixed portion 31.

[0019] As in Fig. 4A and Fig. As shown in Figure 4B, the bracket 30 has a rotation axis (A). When the bracket 30 is rotated about the rotation axis (A) in a predetermined rotation direction r1, the temperature sensor 2 is pressed against the coil end 11E. The rotation axis (A) of the bracket corresponds to a fastening center A, which is an axis of the screw 35 that fastens the bracket to the housing 12 according to the present embodiment. Note that the illustrated rotation direction r1 corresponds to a clockwise direction.

[0020] In the present embodiment, a positional relationship between the coil 11 and the temperature sensor 2 is defined such that a straight extension of a line segment L ( Fig. 2), which connects the rotation axis (A) and the coil end 11E at the shortest distance, passes through a plane center (not shown) of the coil end 11E or a vicinity thereof. sensor element)

[0021] As in Fig. 3A and Fig. 3B, the sensor element 20 includes a thermosensitive element 21, paired lead wires 22 electrically connected to the thermosensitive element 21, a cover body 24 that completely covers the thermosensitive element 21 and parts of the lead wires 22, and a tube 25 that covers predetermined portions of the paired lead wires exposed from the cover body 24.

[0022] The thermosensitive element 21 comprises a thermosensitive body 211, an insulating sealing body 212 covering the thermosensitive body 211, and pairs of sheathed wires 213 projecting from the sealing body 212.

[0023] The thermosensitive body 211 is configured to be capable of detecting a temperature by using a thermistor having electrical resistance that changes its response with a change in temperature or the like.

[0024] The sheath wires 213 are connected to an unillustrated electrode provided on the thermosensitive body 211, and Dumet wires, for example, are used as the sheath wires 213. The paired sheath wires 213 protrude from the sealing body 212 in the same direction. The sheath wires 213 and the lead wires 22 connected to the respective sheath wires 213 constitute "electric wires."

[0025] In the following, a direction in which the sheath wires 213 protrude from the thermosensitive body 211 is referred to as "back," and a direction opposite thereto is referred to as "front." Fig. 1 to Fig. 3B, “front” is designated by a reference symbol F, and “rear” is designated by a reference symbol R.

[0026] The paired lead wires 22 are connected to the respective sheath wires 213 and are connected to a temperature detection circuit (not shown). Each of the lead wires 22 has a core wire 221 connected to the corresponding sheath wire 213 and an insulation coating 222 covering the core wire 221. The paired lead wires 22 protrude from the rear of the cover body 24 and are then folded back to the front.

[0027] In other words, each of the paired lead wires includes a first portion 22A extending rearwardly within the cover body 24, a second portion 22B protruding from the cover body 24 and folded back, and a third portion 22C extending forwardly. When the lead wires 22 are viewed from the stator axial direction D1, the third portions 22C extend forwardly from the second portions 22B parallel to the first portions 22A below the first portions 22A by predetermined lengths. The lead wires 22 are routed in the manner described above, and appropriate portions of the lead wires 22 are held by the bracket 30. As a result, the lead wires 22 can be routed toward the temperature detection circuit while preventing the lead wires 22 from interfering with the coil end 11E.

[0028] The tube 25 is provided on outer peripheries of the third sections 22C. The tube 25 can bundle the paired lead wires 22 and can align the directions of the paired lead wires 22.

[0029] The cover body 24 protects the thermosensitive element 21 and connecting portions 214 of the thermosensitive element 21 and the lead wires 22 from external forces. A front end 24F of the cover body 24 corresponds to a front end of the sensor element 20. The thermosensitive element 21 is arranged near the front end 24F of the cover body 24.

[0030] The cover body 24 is designed to be pressed against the coil end 11EE by rotating the holder 30 in the direction of rotation r1.

[0031] As in Fig. 2, the cover body 24 according to the present embodiment includes a first portion 24A having a relatively short distance from the rotation axis (A) (attachment center A), and a second portion 24B having a relatively long distance from the rotation axis (A) (attachment center A). At the first portion 24A, the cover body 24 is held in a cantilevered manner by a first holding portion 32 of the bracket 30. The second portion 24B covers, for example, the thermosensitive body 211 and is provided on one side near a free end. The second portion 24B is positioned outside a virtual circle VC having a center at the rotation axis (A) and passing through the first portion 24A, in other words, the first holding portion 32. The virtual circle VC is located away from the coil 11.The second portion 24B is positioned at a rear side of the first portion 24A in the rotation direction r1. The second portion 24B is pressed against the coil end 11E by rotating the holder 30 about the rotation axis (A) in the rotation direction r1. During the rotating operation, the first portion 24A, held by the first holding portion 32, remains away from the coil 11 and does not come into contact with the coil 11.

[0032] The cover body 24 extends from a position at a front side of the thermosensitive element 21 to a position at the rear side of the connecting portions 214. The cover body 24 is formed in a long shape in a front-to-back direction. The cover body 24 includes the first portion 24A held by the bracket 30 and the second portion 24B pressed against the coil end 11E. The second portion 24B corresponds to a portion of the cover portion 24 on a side near the thermosensitive body 211. The first portion 24A corresponds to a portion of the cover body 24 on a side near the electric wires (213 and 22).

[0033] The cover body 24 according to the present embodiment has, for example, a columnar appearance. The sensor element 20 and the like are housed within the cover body 24. A diameter of a front end 24F of the cover body 24 is smaller than a diameter of a portion at the rear of the front end 24F. The appearance of the cover body 24 is not limited to a circular shape and may have an optional shape, for example, a rectangular shape.

[0034] The cover body 24 is made of a resin material having elasticity, such as fluororubber and silicone rubber, in a predetermined shape. Elasticity in the present embodiment indicates that when the holder 30 is rotated to press the second portion 24B against the coil 11, the cover body 24 is easily deflected. Examples of fluororubber are polytetrafluoroethylene (PTFE) and a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA). For example, the thermosensitive element 21 and the lead wires 22 are inserted into a PTFE tube, and the tube is contracted by heating, set in a mold, and pressurized. This makes it possible to seal the thermosensitive element 21 and the lead wires 22 with the cover body 24. (bracket)

[0035] The bracket fixes the sensor element 20 to the housing 12 in a state in which the second portion 24B of the cover body 24 is pressed against the coil end 11E.

[0036] The bracket 30 includes the fixed portion 31, which is fixed to the housing 12 with the screw 35, the first holding portion 32, which holds the first portion 24A of the cover body 24 and the tube 25, a second holding portion 33, which holds the tube 25 at the front of the first holding portion 32, and a locking portion 34, which is locked when attached to the housing 12. The first holding portion 32 holds the above-described first portion 24A of the cover body 24.

[0037] The bracket 30 according to the present embodiment is a metal plate member. The fixed portion 31, the first holding portion 32, the second holding portion 33, and the locking portion 34 are integrally formed by manufacturing, such as stamping and folding, a metal plate member such as heat-treated steel.

[0038] Note that the bracket 30 is not limited to the metal plate member and may be made of a resin material having the necessary properties such as strength.

[0039] The fixed portion 31 corresponds to a flat base portion having a screw hole 31A formed in a plate thickness direction. The rotation axis (A) of the bracket 30 is virtually located at a center of the screw hole 31A. The fixed portion 31 is arranged around a hole (not shown) provided in the housing, into which a shank part of the screw 35 is inserted. The hole is provided from the front surface 12A of the housing 12 in the axial direction D1. The shank part of the screw 35 reaches the stator core through the screw hole 31A of the fixed portion 31 and the hole of the housing 12. When a moment acts on the head part 35A of the screw 35 in the rotation direction r1, the bracket 30 is fixed to the housing 12 by axial force of the screw 35 in the axial direction D1.

[0040] Assuming the fastening center A ( Fig. 2), which is the axis of the screw 35, as a center of a dial of a watch and the second holding portion 33 at a position of 12 o'clock, the locking portion 34 is located substantially at a position of 10 o'clock, and the first holding portion 32 is located substantially at a position of 2 o'clock.

[0041] When the bracket 30 is fixed between the screw 35 and the housing 12 and the cover body 24 is pressed against the coil end 11E, the front end 24F of the cover body 24 is positioned behind the line segment L connecting the fixing center A and the coil end 11E at the shortest distance in the rotation direction r1 of the bracket 30. The first portion 24A and the first holding portion 32 are positioned in front of the line segment L in the rotation direction r1.

[0042] The first holding portion 32 is bent upward relative to the fixed portion 31. A fixed piece 321 provided at an upper end of the first holding portion 32 is bent to a side approaching the coil end 11E and folds over the second portion 24B. As a result, the bracket 30 holds the cover body 24 in a cantilevered manner.

[0043] When the fixed portion 31 is fixed between the screw 35 and the housing 12 by fastening the screw 35 and the housing 12, the second portion 24B of the cover body 24 is pressed against the coil end 11E. At this time, the cover body 24 is extended from the first portion 24A to the second portion 24B along an extending direction DC ( Fig. 1) in which the coil wires C extend, is inclined upward while being inclined toward the front surface 12A of the housing 12.

[0044] According to the present embodiment, the first holding portion 32 also holds the lead wires 22 in addition to the cover body 24. The fixing piece 321 of the first holding portion 32 extends further downward than the cover body 24 and crimps the tube 25 covering the third portions 22C of the paired lead wires 22.

[0045] The second holding portion 33 is bent upward with respect to the fixed portion 31, as in the first holding portion 33. The second holding portion 33 has a lower height from the fixed portion 31 than the first holding portion 32. A fixing piece 331 provided at the upper end of the second holding portion 33 is bent toward a side approaching the coil end 11E and folds the tube 25.

[0046] The second holding portion 33 is positioned below the front end 24F of the cover body 24, which extends obliquely upward and forward from the first holding portion 32. As shown in Fig. 2, the second holding portion 33 is further inclined in a plan view in a direction gradually remote from the coil end 11E, from the rear side to the front side. Therefore, the tube 25 is separated from the coil end as the distance from the second holding portion 33 increases. The second holding portion 33 holds the tube 25 substantially parallel to the fixed portion 31.

[0047] Unlike the second holding portion 33, the first holding portion is inclined from the rear side to the front side in a direction gradually approaching the coil end 11E in a plan view.

[0048] The locking portion 34 is bent downward with respect to the fixed portion 31 at a position separated from the fastening center A of the bracket 30. The locking portion 34 corresponds to a side surface 12B of the housing 12 as a locked portion. When the bracket 30 is rotationally operated as a result of the rotating operation of the screw 35 to fasten the screw 35 to the housing 12, the locking portion 34 is locked to the side surface 12B of the housing 12. Therefore, further rotating operation of the bracket 30 is restricted.

[0049] Note that a member to which the locking portion 34 is locked is not limited to the housing 12 and may be any suitable member to which the locking portion 34 abuts when attached. [Mounting the temperature sensor by fastening a screw]

[0050] As described below with reference to Fig. 4A and Fig. 4B, the bracket 30 is fixed between the screw 35 and the housing 12 by fastening the single screw 35 to the housing, which makes it possible to easily and reliably fix the sensor element 20 to the housing 12.

[0051] The holder 30 and the cover body 24 held by the first holding portion 32 are designed to move from a first position P1 in which the second portion 24B is not pressed against the coil end 11E, as shown in Fig. 4A, into a second position P2 in which the second portion 24B is pressed against the coil end 11E, as shown in Fig. 4B, is rotatably operable.

[0052] Before attaching ( Fig. 4A), the holder 30 assumes the first position O1, in which the second section 24B is not pressed against the coil end 11E. At this time, the second section 24B is separated from the coil end 11E, as shown in Fig. 4A. Alternatively, the second portion 24B may come into contact with the coil end 11E as long as the rotational operation of the holder 30 is not prevented.

[0053] When the torque in the rotation direction r1 is applied to the screw 35 as a right-hand screw, the holder 30 is rotationally operated to the second position P2 in the same direction as the rotation direction of the screw 35 as a result of the rotational operation of the screw 35 by friction between the fixed portion 31 and the screw 35, as shown in Fig. 4B, and the fastening is completed. When the holder 30 is rotationally operated from the first position P1 to the second position P2 as described above around the fastening center A, the cover body 24, which is supported by the first holding portion 32, is also rotationally operated in the same direction as the rotation direction of the holder 30. In the illustrated example, the cover body 24 gradually approaches the spool end 11E from the rear side to the front side from a state in which the cover body 24 is substantially along a circumferential direction D2 or a tangent to an outer circumference of the spool 11 ( Fig. 4A), and the second portion 24B is pressed against the coil end 11E from the side. A direction of the pressing force Pr of the cover body 24 acting on the coil end 11E from the outside to the inside in the radial direction D3 is shown by an arrow.

[0054] At this time, the second portion 24B of the cover body 24 is pressed against the coil end 11E along the coil wires C. When the second portion 24B is pressed against the coil end 11E, a distance L2 from the fixing center A to the pressing position B of the second portion 24B against the coil end 11E during the rotating operation becomes smaller than a distance L1.

[0055] The elastic force of the cover body 24 contributes to the pressing force Pr, and the second portion 24B contacts the coil end at a pressure sufficient to hold the second portion 24B at a predetermined position under a condition where vibration or impact is applied. In other words, the cover body 24 forms a pressing mechanism that presses the sensor element 20 against the coil end 11E in cooperation with the holder 30, which is rotationally driven by the rotation of the screw 35.

[0056] In parallel with such rotational operation of the screw 35, the bracket 30, and the cover body 24, the screw also acts in the axial direction D1 to generate an axial force. When the locking portion 34 abuts the side surface 12B of the housing 12, the rotational operation of the bracket 30 is regulated. Therefore, it is possible to firmly fix the bracket 30 to the housing 12 by rotating only the screw 35, while avoiding excessive force acting on the thermosensitive element 21 covered by the cover body 24. [Effects of the present embodiment]

[0057] Main effects by the temperature sensor 2 according to the present embodiment will be described.

[0058] With the temperature sensor 2, the bracket 30 holding the cover body 24 can be fixed to the housing 12 as the fixing object in a state where the cover body 24 covering the thermosensitive body 211 is elastically deformed and pressed against the coil 11. Thus, with the temperature sensor 2, it is possible to prevent the sensor element 20 from deviating from the predetermined position of the coil end 11E due to an external force such as vibration or impact, and to maintain the state where the second portion 24B is pressed against the predetermined position of the coil end 11E at the predetermined pressure. As a result, the temperature of the coil 11 can be stably and accurately detected by temperature detection by the thermosensitive element 21 positioned at the second portion 24B.

[0059] With the temperature sensor 2, the sensor element 20 can be pressed against the coil end 11 using the elastic force of the cover body 24, which covers the thermosensitive body 211 and the like. Thus, with the temperature sensor 2, it is unnecessary to provide another elastic element to obtain the elastic force. This makes it possible to reduce the number of components and simplify the structure.

[0060] The bracket 30 is fixed by fastening the housing 12 and the screw 35, which has the same specification as the screw for fastening the stator core to the housing 12. Therefore, in one operation of assembling the stator core to the housing 12, the temperature sensor 2 can be fixed to the stator 10. As a result, the work efficiency of the assembly is improved, and the number of components can be reduced to reduce costs.

[0061] The cover body 24, which is held by the first holding portion 32 of the bracket 30, is arranged along the extension direction DC of the coil wires C, namely, to be inclined to the axial direction D1. As a result, compared with a case where the cover body 24 is arranged along the axial direction D1 or along a direction orthogonal to the axial direction D1, the second portion 24B can be brought into close contact with the coil wires with a large contact area. This makes it possible to largely secure a heat exchange area from the coil 11 to the sensor element 20 and contribute to improving detection accuracy.

[0062] The bracket 30 is securely fastened between the screw 35 and the housing 12, and the sensor element 20 and the bracket 30 are fixed at two positions of the first holding portion 32 and the second holding portion 33. Therefore, the sensor element 20 is more stably held by the bracket 30 against external forces such as vibration and impact. This contributes to stabilization and improved accuracy of temperature detection.

[0063] Since the first holding portion 32 protrudes upward from the fixed portion 31, the cover body 24 held at the upper end of the first holding portion 32 is separated from the front surface 12A of the housing 12, and a space of a predetermined volume is secured between the housing 12 and the cover body 24. As a result, heat exchange between the stator 10 and the sensor element 20 can be suppressed, and an influence of the stator 10 on the temperature detection of the coil 11 can be suppressed. Note that the stator 10 has a larger heat capacity than the coil 11 and a lower temperature than the coil 11 during operation of the rotating electric machine.

[0064] When the locking portion 34 is locked to the housing 12, excessive rotation of the bracket 30 beyond the second position P2 is restricted. As a result, it is possible to firmly fix the bracket 30 to the housing 12 while preventing damage to the thermosensitive body 211 and the like due to excessive stress. [Modifications]

[0065] Other than the above description, the configurations described in the above-described embodiment may be selected or appropriately changed to the other configurations without departing from the spirit of the present invention.

[0066] The cover body 24 is not limited to the example in which the front end portion is pressed against the coil end 11E, and the pressing position B of the cover body 24 pressed against the coil end 11E may be positioned at the rear side of a front end portion 24f as shown in FIG. Fig. 5. A front extension portion Fx extends forward relative to the cover body 24 in the above-described embodiment.

[0067] Furthermore, the cover body 24 is not limited to the example in which the rear end portion is held by the bracket 30, and a held position H defined by the first holding portion 32 ( Fig. 2) of the holder 30 may be positioned at the front side of a rear end portion 24r, as in the Fig. 5. A rear extension portion Rx extends rearwardly relative to the cover body 24 in the above-described embodiment. Note that the position of the cover body 24 held by the bracket 30 is not limited to the position H shown in Fig. 5, and that the held position H can be located in the rear extension area Rx.

[0068] Both the front extension portion Fx and the rear extension portion Rx do not interfere with the coil end 11E in the process of rotating the holder 30. Note that the rear extension portion Rx may be bent to a side away from the coil end 11E with respect to a central portion M.

[0069] In order to fix the temperature sensor according to the present invention to the fixing object, such as the housing 12 of the stator 10, a nut 37 can be used as a female screw element, as shown in Fig. 6B, or a rivet 38 can be used as in Fig. 6C, in addition to the use of screw 35 as shown in Fig. 6A.

[0070] The nut 37 is secured with a male bolt 121 inserted into the bolt hole of the housing 12. When the torque in the rotation direction r1 is applied to the nut 37, the bracket 30 is also rotated around the rotation center (A) due to the rotation of the nut 37 due to friction between the nut 37 and the bracket 30, and the cover body 24 is accordingly pressed against the coil end 11E.

[0071] In a case of using the rivet 38, the rotation center is also located in the screw hole 31A of the bracket 30, into which a shaft part 381 is inserted. Therefore, before fastening, the bracket 30 can be rotated to press the cover body 24 against the spool end 11E. In the state where the cover body 24 is pressed against the spool end 11E, a load is preferably applied in an axial direction to the rivet 38 to fasten the rivet 38.

[0072] Although not shown, the bracket can be fixed to the housing 12 by supplying a resin material in a flowing state, a molten metal, or the like into an internal space of the screw hole 31A of the bracket 30 and the hole of the housing 12, and curing the supplied material. In this case, too, the bracket 30 is rotated about the rotation axis A to press the cover body 24 against the coil end 11E.

[0073] The sensor element 20 according to the above-described embodiment is fixed to the bracket 30 by crimping the first portion 24A of the cover body 24 with the fixing piece 321 of the first holding portion 32; however, the sensor element 20 may be fixed to the bracket 30 by a suitable method other than crimping. The first portion 24A may be held by the first holding portion of the bracket, for example, using a screw or a rivet. Alternatively, the first portion 24A may be fixed to the first holding portion 32 of the bracket 30 by an insert molding method in which the bracket 30 is placed in a mold for molding the cover body 24.

[0074] The lead wires 22 are not necessarily folded back behind the cover body 24. The lead wires 22 can be laid in a suitable direction with a suitable path while preventing interference with the coil 11 and other elements. Depending on a diameter of the coil end 11E, a mounting angle of the temperature sensor 2 to the coil end 11E, and the like, the paired lead wires 22 protruding from the cover body 24 can extend in a rearward direction, behind the cover body 24.

[0075] The second holding portion 33, which holds the lead wires 22, can be provided at a suitable position of the bracket 30 as needed. For example, the second holding portion 33 can be arranged in front of the first holding portion 32 in the rotation direction r1.

[0076] It is assumed that an upper limit of the fastening force (torque) of a tool that fastens the screw 35 (or nut 37) is set. In such a case, the bracket can be reliably fastened by the axial force of the screw 35 (or nut 37) even if the locking portion 34 is not provided on the bracket 30, and the bracket 30 can be held in the second position P2 without applying excessive stress to the thermosensitive element 21 upon completion of the fastening.

[0077] Note that the male screw member used to fix the bracket 30 is not limited to the screw, and may be another member including a male screw, such as a screw.

[0078] The object to which the fixed portion 31 of the bracket 30 is attached is not limited to the housing 12 and may be another member of the stator 10 or a member arranged around the stator 10.

[0079] The example in which the second portion 24B covers the thermosensitive body 211 has been described; however, the present invention is not limited thereto. In other words, the temperature can be detected as long as the thermosensitive body 211 is provided near the second portion 24B, which is pressed against the coil 11. List of reference symbols 1 Rotating electrical machine 2 temperature sensors 10 Stator 11 coil 11E Coil end 12 Housing (fixation object, locked section) 12A Front surface 12B Lateral surface 20 sensor element 21 Thermosensitive 22 Lead wire 22A First Section 22B Second Section 22C Third Section 24 cover bodies 24A First Section 24B Second Section 24F Front end 25 tubes 30 bracket 31 Fixed section (base section) 31A screw hole 32 First stopping section 33 Second stopping section 34 Locking section 35 Screw (screw element) 35A headboard 36 Washer 37 mother 38 rivets 121 Male screw 211 Thermosensitive body 212 sealing bodies 213 sheathed wire 214 connecting section 221 core wire 222 Insulating coating 321 Fixing piece 331 Fixing piece 381 shaft part A Mounting center (rotation axis) B Contact position C Coil wire D1 Axial direction D2 circumferential direction D3 Radial direction DC extension direction F Front Fx Front extension direction H Held Position M Middle range R back Rx Rear extension direction Pr Press force L line segment L1, L2 distance P1 First position P2 Second position r1 direction of rotation VC Virtual Circle

Claims

[1] Temperature sensor (2) for detecting a temperature of a coil (11) provided in a stator (10) of a rotating electrical machine (1), the temperature sensor (2) comprising: a sensor element (20) having a thermosensitive body (211), an electric wire (213, 22) electrically connected to the thermosensitive body (211), and a cover body (24) made of a resin material having elasticity and covering a part of the electric wire and the thermosensitive body (211); and a holder (30) having a rotation axis, which is designed to hold the cover body (24) in a cantilevered manner, wherein the cover body (24) has a first portion (24A) which is at a relatively short distance from the rotation axis (A) and is held by the holder (30), and a second portion (24B) which is at a relatively large distance from the rotation axis (A) and covers the thermosensitive body (211), the second section (24B) is located outside a virtual circle (VC) which passes through the first section (24A) and has the axis of rotation (A) as its center, wherein the cover body (24) is designed to be pressed against the coil (11) by a rotational operation of the cover body (24) in the same direction as a direction of rotational operation of the holder (30) from outside to inside in the radial direction (D3) of the coil (11). [2] The temperature sensor (2) according to claim 1, wherein the second portion (24B) is positioned at a rear side of the first portion (24A) in a direction of rotational operation of the bracket (30). [3] Temperature sensor (2) according to claim 2, wherein when the cover body (24) is pressed against the coil (11), the second portion (24B) is positioned behind a line segment connecting the rotation axis (A) and the coil (11) at a minimum distance in the direction of rotation of the holder (30), and the first section (24A) is positioned in front of the line segment in the direction of rotational operation of the holder (30). [4] Temperature sensor (2) according to claim 1, wherein the holder (30) is attached to a fixing object by fastening a screw element and the fixing object, and the cover body (24) is designed to be pressed against the coil (11) by rotating the holder (30) with rotation for fastening the screw element to the fixing element. [5] The temperature sensor (2) according to claim 4, wherein the bracket (30) is fixed together with a core of the stator (10) to a housing (12) of the stator (10) as the fixing object by the screw member that fixes the core to the housing (12). [6] The temperature sensor (2) according to claim 4, wherein the bracket (30) has a locking portion (34) locked to a locked portion to limit excessive rotation. [7] Temperature sensor (2) according to claim 1, wherein the cover body (24) is arranged along an extension direction in which wires of the coil (11) extend. [8] The temperature sensor (2) according to claim 1, wherein the holder (30) has a first holding portion (32) configured to hold the cover body (24) and a second holding portion (32) configured to hold the electric wire at a front side of the first holding portion (32) in a direction of rotational operation. [9] The temperature sensor (2) according to claim 6, wherein the bracket (30) comprises a base portion (31) having a screw hole (31A) into which the screw member (35) is inserted, a holding portion (32) bent with respect to the base portion (31) and configured to hold the cover body (24), and the locking portion (34) formed by bending in a direction opposite to the holding portion (32) with respect to the base portion (31). [10] Rotating electrical machine, comprising: a stator (10) with a core and a coil (11); a rotor configured to be rotated relative to the stator (10); and the temperature sensor (2) according to one of claims 1 to 9, which is designed to detect a temperature of the coil (11).

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