Temperature measurement part structure

Abstract

This temperature measurement part structure is the structure of a temperature measurement part for measuring temperature of a coil of a motor. The temperature measurement part structure is provided with a temperature sensor and a fixture being electrically conductive and for fixing the temperature sensor to an energization part of the coil. The fixture has: a body part for bringing the rear surface of the temperature sensor into contact with the energization part while in the state of being in contact with the front surface of the temperature sensor; a first welding fixation part extending from the body part and being welded and fixed to a section of the energization part on the high potential side; and a second welding fixation part extending from a section of the body part different from the first welding fixation part and being welded and fixed to a section of the energization part on the low potential side relative to the first welding fixation part.

Description

Temperature measurement part structure

[0001] The present invention relates to a temperature measurement unit structure.

[0002] WO2020 / 026394A discloses a temperature detection device that includes a bracket for attaching a temperature sensor to a coil.

[0003] The bracket includes a bracket body that is fixed to the coil, and a heat collecting portion that holds the temperature sensor in a surrounding state.

[0004] In the temperature detection device, the heat collecting part surrounding the temperature sensor is in close contact with the coil, and thus the temperature sensor is not in direct contact with the coil, resulting in a decrease in responsiveness.

[0005] The present invention has been made in view of the above problems, and has as its object to provide a temperature measurement section structure that can improve responsiveness during measurement.

[0006] According to one aspect of the present invention, a temperature measurement unit structure is a temperature measurement unit structure for measuring the temperature of a coil of a motor. The temperature measurement unit structure includes a temperature sensor and a conductive fixture that fixes the temperature sensor to a current-carrying portion of the coil. The fixture has a main body portion that contacts the front surface of the temperature sensor and brings the back surface of the temperature sensor into contact with the current-carrying portion, and a first welded-fixing portion that extends from the main body portion and is welded to a portion of the current-carrying portion on the high-potential side. The fixture has a second welded-fixing portion that extends from a portion of the main body portion different from the first welded-fixing portion and is welded to a portion of the current-carrying portion on the low-potential side of the first welded-fixing portion.

[0007] Fig. 1 is a perspective view showing a temperature measurement unit structure according to this embodiment. Fig. 2 is a plan view showing a state in which a part of a fixing device of the temperature measurement unit structure according to this embodiment is cut away. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is an explanatory diagram showing how current flows through the fixing device. Fig. 5 is a perspective view showing a temperature measurement unit structure according to a modified example.

[0008] <Embodiments> Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0009] Fig. 1 is a perspective view showing the temperature measurement unit structure according to this embodiment. Fig. 2 is a plan view showing a state in which a part of a fixing device 24 of the temperature measurement unit structure according to this embodiment is cut away. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.

[0010] The temperature measurement unit structure according to this embodiment is a temperature measurement unit 1 for measuring the temperature of a coil of a motor. The motor may be, for example, a motor that constitutes a drive source for an electric vehicle (not shown). The motor may also be a three-phase motor.

[0011] The motor includes, for example, a coil (not shown) wound around a stator. The coil is made of a winding 12 (see FIG. 5 ) wound around the stator. The winding 12 is made of copper or aluminum. In this embodiment, the winding 12 is made of copper.

[0012] The winding 12 is made of a flat rectangular winding wire, and the coil is a rectangular wire coil formed from the rectangular winding wire. The portion of the winding 12 that is wound around the stator to form the coil, extending from the stator, constitutes the coil end 14 (see FIG. 5).

[0013] As shown in Fig. 1, the bus bar 10 is a conductive plate electrically connected to a coil end 14 (see Fig. 5) formed of a part of the winding 12. The bus bar 10 is made of copper or aluminum. In this embodiment, the bus bar 10 is made of copper.

[0014] The busbar 10 supplies power to the coils. Specifically, the busbar 10 supplies power from an inverter (not shown) to the coils, electrically connects the coil ends 14 (see FIG. 5 ) of the coils to each other, and is electrically connected to the neutral points of the Y-connected coils to relay the neutral points. The busbar 10 of this embodiment constitutes a relay busbar electrically connected to the neutral points of the Y-connected coils.

[0015] As shown in FIG. 1, the temperature measurement structure according to this embodiment includes a temperature sensor 20 and a conductive fixture 24 that fixes the temperature sensor 20 to a current-carrying portion 22 of a coil of a motor.

[0016] The current-carrying portion 22 of the coil is formed by a bus bar 10 electrically connected to the coil end 14 (see FIG. 5) of the coil extending from the stator of the motor.

[0017] (Conductor) The conductive portion 22 is a long, flat plate made of a conductive metal. The conductive portion 22 has a plurality of bent portions 30 extending in the width direction and spaced apart in the longitudinal direction. This allows the conductive portion 22 to be arranged along a cylindrical stator (not shown) from which the coil ends 14 (see FIG. 5) extend.

[0018] A voltage is applied to the current-carrying portion 22 so that the potential at the other longitudinal end is higher than that at the one longitudinal end. The one longitudinal end constitutes a low potential side 40, and the other longitudinal end constitutes a high potential side 42. As a result, a current flows through the current-carrying portion 22 from the other longitudinal end to the one longitudinal end.

[0019] Rectangular notches 48 are formed in multiple locations on one side edge 44 of the current-carrying portion 22. A sensor mounting portion 50 is provided in the middle of the current-carrying portion 22, at a location sandwiched between adjacent notches 48. The sensor mounting portion 50 does not have the bent portion 30 described above. This gives the sensor mounting portion 50 a flat shape.

[0020] The sensor mounting portion 50 has a narrower width than the other portions of the current-carrying portion 22. The mounting portion one side edge 44A of the sensor mounting portion 50 is located closer to the other side edge 46 than the one side edge 44 of the other portion of the current-carrying portion 22. On the other hand, the mounting portion other side edge 46A of the sensor mounting portion 50 extends in line with the other side edge 46 of the other portion of the current-carrying portion 22.

[0021] A busbar notch 60 is formed in the longitudinal center of one mounting edge 44A of the sensor mounting portion 50 as a rectangular notch that is long in the longitudinal direction of the current-carrying portion 22. As a result, the current-carrying portion 22 includes the busbar notch 60 as a notch in the sensor mounting portion 50, which is the portion where the temperature sensor 20 is disposed.

[0022] A busbar narrow portion 50A having a narrow width is formed at the portion of the sensor mounting portion 50 where the busbar cutout 60 is provided. As a result, the cross-sectional area of ​​the sensor mounting portion 50 in the width direction is reduced at the busbar narrow portion 50A, and the current density of the current flowing through the sensor mounting portion 50 is increased at the busbar narrow portion 50A.

[0023] The cross-sectional area of ​​the narrow busbar portion 50A is determined based on an allowable heat generation temperature determined, for example, by experiment, so that the current-carrying portion 22 does not generate abnormal heat when the motor is operating.

[0024] One longitudinal end of the current-carrying portion 22, separated by the busbar notch 60, is the low potential side 40, and the other longitudinal end of the current-carrying portion 22, separated by the busbar notch 60, is the high potential side 42, which is the high potential side.

[0025] 1 and 2, the temperature sensor 20 is composed of a thermistor. A thermistor is an electronic component whose electrical resistance changes with temperature. The resistance of a thermistor decreases as the temperature increases and increases as the temperature decreases.

[0026] 2, the temperature sensor 20 includes a rectangular plate-shaped casing 20K. The casing 20K is made of an insulating material. A thermistor element 21 is embedded in the tip of the casing 20K.

[0027] The temperature sensor 20 has a harness 20C connected to a thermistor element 21 extending from the base end surface. The harness 20C is connected to a temperature detection device (not shown) or the like. The temperature detection device measures the motor temperature based on the detection result of the temperature sensor 20. The measured motor temperature is used, for example, for control purposes to protect the motor when the motor temperature rises above a specified temperature.

[0028] (Fixing Tool) The fixing tool 24 is made of a metal plate that is both conductive and elastic. Examples of conductive metals include copper and aluminum.

[0029] The fixing device 24 is made of a metal having the same electrical conductivity as the current-carrying portion 22. When the current-carrying portion 22 is made of copper, the fixing device 24 is also made of copper. When the current-carrying portion 22 is made of aluminum, the fixing device 24 is also made of aluminum. In this embodiment, the fixing device 24 is made of copper, just like the current-carrying portion 22.

[0030] 3 , the fixture 24 has a main body 70 that contacts the front surface 20A of the temperature sensor 20 and brings the back surface 20B of the temperature sensor 20 into contact with the current-carrying portion 22. The fixture 24 has a first welded and fixed portion 72 that extends from the main body 70 and is welded and fixed to a portion on the high potential side 42 of the current-carrying portion 22. The fixture 24 has a second welded and fixed portion 74 that extends from a different portion of the main body 70 from the first welded and fixed portion 72 and is welded and fixed to a portion closer to the low potential side 40 of the current-carrying portion 22 than the first welded and fixed portion 72.

[0031] As shown in FIG. 1, the main body 70 is formed in a rectangular shape extending in the longitudinal direction of the temperature sensor 20 which is formed in a rectangular shape.

[0032] A first extending piece 82 is provided on the tip side, which is one longitudinal end of the main body 70, extending to one widthwise side of the main body 70 via a first bent portion 80 that bends along one side surface 20D of the attached temperature sensor 20. A second extending piece 86 is provided on the tip side, which is one longitudinal end of the main body 70, extending to the other widthwise side of the main body 70 via a second bent portion 84 that bends along the other side surface 20E of the attached temperature sensor 20.

[0033] Furthermore, a third extending piece 92 is provided on the base end side, which is the other longitudinal end side of the main body 70, extending to one widthwise side of the main body 70 via a third bent portion 90 that bends along one side surface 20D of the attached temperature sensor 20. A fourth extending piece 96 is provided on the base end side, which is the other longitudinal end side of the main body 70, extending to the other widthwise side of the main body 70 via a fourth bent portion 94 that bends along the other side surface 20E of the attached temperature sensor 20.

[0034] In the temperature measurement unit structure according to this embodiment, the first extension piece 82 and the third extension piece 92 constitute a first welding-fixing portion 72 that is welded to a portion of the high potential side 42 of the current-carrying portion 22. The second extension piece 86 and the fourth extension piece 96 constitute a second welding-fixing portion 74 that is welded to a portion of the low potential side 40 of the current-carrying portion 22.

[0035] The amount of protrusion of each of the bending portions 80, 84, 90, and 94 from the main body 70 in the bending direction is set to match the thickness dimension of the temperature sensor 20. As a result, when the main body 70 is brought into surface contact with the front surface 20A of the temperature sensor 20 and the extension pieces 82, 86, 92, and 96 are welded and fixed to the current-carrying portion 22, the elasticity of the fixing device 24 presses the back surface 20B (see FIG. 3 ) of the temperature sensor 20 against the current-carrying portion 22 in surface contact.

[0036] A holder 100 is provided at the tip of the main body 70. The holder 100 holds the tip of the temperature sensor 20. A step 20F (see FIG. 5) is formed on the rear surface 20B at the tip of the temperature sensor 20, and the thickness of the tip of the temperature sensor 20 is smaller than the other portions.

[0037] The holding portion 100 has a first holding piece 100A extending to one widthwise side of the main body 70, further distal than the first extending piece 82. The holding portion 100 has a second holding piece 100B extending to the other widthwise side of the main body 70, further distal than the second extending piece 86.

[0038] The first holding piece 100A is bent along one side surface 20D of the temperature sensor 20 to be attached, and then bent toward a step 20F (see FIG. 5) formed on the back surface 20B of the temperature sensor 20. The second holding piece 100B is bent along the other side surface 20E of the temperature sensor 20 to be attached, and then bent toward the step 20F (see FIG. 5) formed on the back surface 20B of the temperature sensor 20.

[0039] As a result, the fixture 24 is attached to the temperature sensor 20 with the holding portion 100 holding the tip of the temperature sensor 20 .

[0040] The fixture 24 holding the temperature sensor 20 is placed on the sensor attachment portion 50 so that the temperature sensor 20 extends in the width direction of the current-carrying portion 22. At this time, the fixture 24 is placed so that the holding portion 100 holding the temperature sensor 20 protrudes from the other side edge 46 of the current-carrying portion 22.

[0041] Furthermore, the temperature sensor 20 is disposed so as to cross the busbar notch 60 formed in the sensor mounting portion 50 at the longitudinal center of the busbar notch 60. In other words, the busbar notch 60 extends so as to cross the temperature sensor 20 along the current flow direction F.

[0042] In this arrangement, the second extension piece 86 and the fourth extension piece 96 are arranged at one longitudinal end side of the busbar cutout 60, and the second extension piece 86 and the fourth extension piece 96 are arranged opposite the current-carrying portion 22 on the low potential side 40 of the busbar cutout 60. In addition, the first extension piece 82 and the third extension piece 92 are arranged at the other longitudinal end side of the busbar cutout 60, and the first extension piece 82 and the third extension piece 92 are arranged opposite the current-carrying portion 22 on the high potential side 42 of the busbar cutout 60.

[0043] 3, the extension pieces 82, 86, 92, and 96 are fixed to the current-carrying portion 22 by welding. Spot welding, for example, can be used to fix the extension pieces 82, 86, 92, and 96. As a result, the extension pieces 82, 86, 92, and 96 are electrically connected to the current-carrying portion 22 by the welds 110.

[0044] Furthermore, since the fixture 24 is fixed to the current-carrying part 22 by welding, the protruding part is reduced compared to when the fixture 24 is fixed by a crimping structure or bolts, which allows the fixture 24 to be installed in a narrow space such as the end of the stator of a motor.

[0045] Furthermore, since the fixture 24 is fixed to the current-carrying portion 22 by welding, the heat capacity is reduced compared to when the fixture 24 is fixed by a crimping structure or bolts.

[0046] 4 is an explanatory diagram showing how current flows through the fixing device 24. A part of the current flowing through the sensor mounting portion 50 flows through a first path 120 that passes through the busbar narrow portion 50A formed in the sensor mounting portion 50. The busbar narrow portion 50A of the sensor mounting portion 50 generates heat in accordance with the magnitude of the current flowing through the first path 120.

[0047] A portion of the current flowing through the sensor mounting portion 50 flows through a second path 122 that passes through the first extension piece 82, the main body portion 70, and the second extension piece 86 of the fixing device 24. The portion of the main body portion 70 located between the first extension piece 82 and the second extension piece 86 generates heat in accordance with the magnitude of the current flowing through the second path 122.

[0048] A portion of the current flowing through the sensor mounting portion 50 flows through a third path 124 that passes through the third extension piece 92, the main body portion 70, and the fourth extension piece 96 of the fixture 24. The portion of the main body portion 70 located between the third extension piece 92 and the fourth extension piece 96 generates heat in accordance with the magnitude of the current flowing through the third path 124.

[0049] (Operations and Effects) As described above, the temperature measurement unit structure of this embodiment is a structure of the temperature measurement unit 1 that measures the temperature of a motor coil. The temperature measurement unit structure includes a temperature sensor 20 and a conductive fastener 24 that fastens the temperature sensor 20 to the current-carrying portion 22 of the coil. The fastener 24 has a main body 70 that contacts the front surface 20A of the temperature sensor 20 and brings the back surface 20B of the temperature sensor 20 into contact with the current-carrying portion 22. The fastener 24 has a first welded and fixed portion 72 that extends from the main body 70 and is welded and fixed to a portion of the high-potential side 42 of the current-carrying portion 22. The fastener 24 has a second welded and fixed portion 74 that extends from a portion of the main body 70 different from the first welded and fixed portion 72 and is welded and fixed to a portion of the low-potential side 40 of the current-carrying portion 22 closer to the first welded and fixed portion 72.

[0050] In this configuration, the back surface 20B of the temperature sensor 20 fixed by the fixture 24 contacts the current-carrying part 22 of the coil. Therefore, compared to when a heat collecting part surrounding the temperature sensor 20 is interposed between the temperature sensor 20 and the current-carrying part 22, it is possible to improve the responsiveness during measurement.

[0051] In this embodiment, a first welded fixing portion 72 extending from the main body portion 70 in contact with the surface 20A of the temperature sensor 20 is welded to a portion on the high potential side 42 of the current-carrying portion 22. A second welded fixing portion 74 extending from a portion of the main body portion 70 different from the first welded fixing portion 72 is welded to a portion on the low potential side 40 of the current-carrying portion 22 closer to the first welded fixing portion 72. In the main body portion 70 in contact with the surface 20A of the temperature sensor 20, a current flows between the extending portion of the first welded fixing portion 72 fixed to the high potential side 42 and the extending portion of the second welded fixing portion 74 welded to the low potential side 40.

[0052] Therefore, heat generated in the current-carrying portion 22 by the current flowing through the current-carrying portion 22 is transferred to the back surface 20B of the temperature sensor 20. Furthermore, heat generated in the main body portion 70 of the fixing device 24 by the current flowing through the main body portion 70 is transferred to the front surface 20A of the temperature sensor 20. As a result, heat generated in response to the motor current flowing through the motor is applied to the front surface 20A and back surface 20B of the temperature sensor 20. Therefore, the temperature sensor 20 can detect temperature changes in response to current changes with higher accuracy than when heat from the current-carrying portion 22 is transferred to the temperature sensor 20 via a heat collector.

[0053] Since the welded fixing portions 72, 74 are welded to the current-carrying portion 22, they can be installed in a smaller space than when they are fixed with a crimped structure or bolts. Furthermore, the increase in heat capacity of the fixing device 24 is suppressed compared to when the welded fixing portions 72, 74 are fixed with a crimped structure or bolts, which allows for further improvement in responsiveness.

[0054] Furthermore, the fixing device 24 has elasticity, and the temperature sensor 20 is pressed against the current-carrying part 22 by the elasticity of the fixing device 24. This allows the temperature sensor 20 to be in close contact with the current-carrying part 22, further improving the measurement accuracy of the temperature sensor 20.

[0055] Furthermore, the main body 70 in contact with the temperature sensor 20 is connected to the welded fixing portions 72, 74 via bent portions 80, 84, 90, 94 provided on the side edges. Therefore, the length from the main body 70 to the welded fixing portions 72, 74 is longer by the length of the bent portions 80, 84, 90, 94. This enables the fixing device 24 to suppress the effect on the temperature sensor 20 of the heat generated when the welded fixing portions 72, 74 are welded.

[0056] In addition, in this embodiment, the current-carrying portion 22 has a busbar notch 60 as a notch at the location where the temperature sensor 20 is placed, and the busbar notch 60 extends across the temperature sensor 20 along the flow direction F of the current.

[0057] In this configuration, the cross-sectional area of ​​the busbar narrow portion 50A, which is the portion of the current-carrying portion 22 that has the busbar notch 60, is reduced. This increases the current density in the busbar narrow portion 50A, making it more likely to generate heat. Therefore, the temperature sensor 20 is disposed in a portion where the temperature is likely to increase depending on the magnitude of the motor current flowing through the motor, making it possible to accurately grasp the heat generation state and detect abnormal heat generation early.

[0058] In this embodiment, the fixture 24 is made of a metal having the same electrical conductivity as the current-carrying portion 22 .

[0059] In such a configuration, the fixing device 24 and the current-carrying portion 22 have the same electrical conductivity, and therefore, it becomes easy to design when adjusting the cross-sectional area of ​​the current-carrying portion 22 that is lost by forming, for example, a busbar notch 60 as a notch, and the cross-sectional area of ​​the portion of the fixing device 24 through which current flows.

[0060] In this embodiment, the current-carrying portion 22 on which the temperature sensor 20 is disposed is the bus bar 10 electrically connected to the coil.

[0061] In such a configuration, if the current-carrying part 22 is, for example, a bus bar 10 connected to an inverter, there is generally space around the bus bar 10 due to the structure of the motor, which makes it possible to improve workability when installing, for example, a temperature sensor 20.

[0062] In particular, in this embodiment, the current-carrying portion 22 on which the temperature sensor 20 is disposed is a relay bus bar electrically connected to the neutral point of the Y-connected coil.

[0063] In this configuration, it is relatively easy to secure a working space around the relay bus bar, improving workability. Furthermore, the relay bus bar is located in a position where heat tends to accumulate. Therefore, this embodiment makes it possible to measure the temperature of a location where heat tends to accumulate and where conditions are relatively severe.

[0064] In this embodiment, the fixing device 24 includes a main body 70 formed in a rectangular shape and extending in the longitudinal direction of the temperature sensor 20, and a first extending piece 82 extending from one longitudinal end of the main body 70 to one widthwise side of the main body 70. The fixing device 24 also includes a second extending piece 86 extending from one longitudinal end to the other widthwise side of the main body 70, a third extending piece 92 extending from the other longitudinal end of the main body 70 to one widthwise side, and a fourth extending piece 96 extending from the other longitudinal end to the other widthwise side. The first extending piece 82 and the third extending piece 92 constitute a first welding fixing portion 72, and the second extending piece 86 and the fourth extending piece 96 constitute a second welding fixing portion 74.

[0065] By adopting such a configuration, the above-mentioned fixing tool 24 can be formed.

[0066] <Modification> Next, a temperature measurement unit structure according to a modification will be described with reference to Fig. 5. In the modification, parts that are the same as or equivalent to those in the above-described embodiment will be assigned the same reference numerals and descriptions thereof will be omitted, and only parts that differ from the embodiment will be described.

[0067] (Electrifying Section) FIG. 5 is a perspective view showing a temperature measuring section structure according to a modified example.

[0068] As shown in FIG. 5, the current-carrying portion 22 in which the temperature sensor 20 is disposed is formed by the coil end 14 of a coil made of rectangular wire.

[0069] The current-carrying portion 22 has a rectangular cross section. In FIG. 5 , the current-carrying portion 22 has an upper surface 200 and a lower surface 202. The current-carrying portion 22 also has a front side 204 and a rear side 206. The first surface 200 and the second surface 202 are narrower than the first surface 204 and the second surface 206.

[0070] The temperature sensor 20 with the fixture 24 attached is placed on the one surface 200 side of the current-carrying part 22. The temperature sensor 20 is fixed to the current-carrying part 22 with the longitudinal direction of the temperature sensor 20 aligned with the longitudinal direction of the current-carrying part 22. As a result, the back surface 20B of the temperature sensor 20 is in surface contact with the one surface 200 of the current-carrying part 22 over its entire length.

[0071] The current-carrying portion 22 has a coil notch 210 as a notch in a portion of the other surface 202 opposite to the portion of the one surface 200 where the temperature sensor 20 is arranged. The coil notch 210 extends along the flow direction F of the current.

[0072] At the portion of the current-carrying portion 22 where the coil notch 210 is provided, a narrow coil portion 212 is formed, in which the distance from the one surface 200 to the other surface 202 is narrow. As a result, the cross-sectional area of ​​the current-carrying portion 22 is reduced at the narrow coil portion 212, and the current density of the current flowing through the current-carrying portion 22 is increased at the narrow coil portion 212.

[0073] The fixture 24 is made of a metal plate that is both conductive and elastic. Examples of conductive metals include copper and aluminum.

[0074] The fixing device 24 is made of a metal having the same electrical conductivity as the current-carrying portion 22 that constitutes the coil end 14. If the current-carrying portion 22 is made of copper, the fixing device 24 is also made of copper. If the current-carrying portion 22 is made of aluminum, the fixing device 24 is also made of aluminum. In this embodiment, the fixing device 24 is made of copper, just like the current-carrying portion 22.

[0075] The first extending piece 82 and the third extending piece 92 of the fixing device 24 are arranged along one side surface 204 of the current-carrying portion 22. The first extending piece 82 and the third extending piece 92 are welded and fixed to the current-carrying portion 22 in a state of surface contact with the one side surface 204 of the current-carrying portion 22.

[0076] The second extending piece 86 (not shown) and the fourth extending piece 96 (not shown) of the fixing device 24 are arranged along the other side surface 206 of the current-carrying portion 22. The second extending piece 86 (not shown) and the fourth extending piece 96 (not shown) are welded and fixed to the current-carrying portion 22 in a state of surface contact with the other side surface 206 of the current-carrying portion 22.

[0077] The first extension piece 82 and the second extension piece 86 (not shown) are arranged on the low potential side 40 of the current-carrying portion 22. The third extension piece 92 and the fourth extension piece 96 (not shown) are arranged on the high potential side 42 of the current-carrying portion 22 relative to the first extension piece 82 and the second extension piece 86 (not shown).

[0078] As a result, the third extension piece 92 and the fourth extension piece 96 (not shown) constitute a first welded and fixed portion 72 that is welded and fixed to the high potential side 42 of the current-carrying portion 22. The first extension piece 82 and the second extension piece 86 (not shown) constitute a second welded and fixed portion 74 that is welded and fixed to the low potential side 40 of the current-carrying portion 22.

[0079] (Current Path) A portion of the current flowing through the current-carrying unit 22 flows through a fourth path 230 that passes through the narrow coil portion 212 formed in the current-carrying unit 22. The narrow coil portion 212 of the current-carrying unit 22 generates heat in accordance with the magnitude of the current flowing through the fourth path 230.

[0080] A portion of the current flowing through the current-carrying portion 22 flows through a fifth path 232 that passes through the third extension piece 92, the main body 70, and the first extension piece 82 of the fixing device 24. The portion of the main body 70 located between the third extension piece 92 and the first extension piece 82 generates heat in accordance with the magnitude of the current flowing through the fifth path 232.

[0081] A portion of the current flowing through the current-carrying portion 22 flows through a sixth path (not shown) that passes through the fourth extension piece 96 (not shown), the main body 70, and the second extension piece 86 (not shown) of the fixing device 24. The portion of the main body 70 located between the fourth extension piece 96 and the second extension piece 86 generates heat in accordance with the magnitude of the current flowing through the sixth path (not shown).

[0082] (Functions and Effects) In this modification, the same functions and effects as those of the embodiment can be achieved with respect to the same or equivalent parts as those of the embodiment.

[0083] In addition, in this modified example, the current-carrying portion 22 has a coil notch 210 as a notch on the side opposite to the portion where the temperature sensor 20 is arranged, and the coil notch 210 extends along the flow direction F of the current.

[0084] In this configuration, the cross-sectional area of ​​the narrow coil portion 212 of the current-carrying portion 22, which is the portion having the coil cutout 210, is reduced. This increases the current density in the narrow coil portion 212, making it more likely to generate heat. Therefore, the temperature sensor 20 is disposed in a portion where the temperature is likely to increase as the motor current increases, making it possible to accurately grasp the heat generation state and detect abnormal heat generation early.

[0085] In this modification, the fixture 24 is made of a metal having the same electrical conductivity as the current-carrying portion 22 .

[0086] In such a configuration, the fixing device 24 and the current-carrying portion 22 have the same electrical conductivity, so it is possible to easily design the device to adjust the cross-sectional area of ​​the current-carrying portion 22 that is lost by forming the coil notch 210, for example, and the cross-sectional area of ​​the portion of the fixing device 24 through which current flows.

[0087] In this modification, the current-carrying portion 22 where the temperature sensor 20 is arranged is the coil end 14 of the coil.

[0088] In such a configuration, the coil ends 14 of the motor are generally located in a position where heat tends to accumulate. Therefore, this embodiment makes it possible to measure the temperature of a portion where heat tends to accumulate and where conditions are severe.

[0089] In this modified example, the fixing device 24 includes a main body 70 that extends in the longitudinal direction of the rectangular temperature sensor 20. The fixing device 24 includes a first extending piece 82 that extends from one longitudinal end of the main body 70 toward one widthwise side of the main body 70, and a second extending piece 86 that extends from the one longitudinal end toward the other widthwise side of the main body 70. The fixing device 24 also includes a third extending piece 92 that extends from the other longitudinal end of the main body 70 toward one widthwise side, and a fourth extending piece 96 that extends from the other longitudinal end toward the other widthwise side. The third extending piece 92 and the fourth extending piece 96 form a first welded fixing portion 72, and the first extending piece 82 and the second extending piece 86 form a second welded fixing portion 74.

[0090] By adopting such a configuration, the above-mentioned fixing device 24 can be formed.

[0091] The above describes embodiments and modifications of the present invention, but the above embodiments and modifications merely illustrate some of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments and modifications.

[0092] The temperature measurement unit structures of the present embodiment and the modified examples described above have been explained using the example of application to a motor mounted on an electric vehicle, but the temperature measurement unit structure may also be applied to a motor used in a drive device.

Claims

1. A temperature measurement unit structure for measuring the temperature of a motor coil, comprising: a temperature sensor; and a conductive fixture for fixing the temperature sensor to a current-carrying part of the coil, wherein the fixture has: a main body portion that contacts the front surface of the temperature sensor and brings the back surface of the temperature sensor into contact with the current-carrying part; a first welded and fixed part extending from the main body portion and welded and fixed to a part on the high potential side of the current-carrying part; and a second welded and fixed part extending from a part of the main body portion different from the first welded and fixed part and welded and fixed to a part on the low potential side of the current-carrying part relative to the first welded and fixed part.

2. A temperature measurement unit structure according to claim 1, wherein the current-carrying section has a notch at the location where the temperature sensor is disposed, and the notch extends across the temperature sensor in the direction of current flow.

3. A temperature measuring section structure according to claim 2, wherein the fixing device is made of a metal having the same electrical conductivity as the current-carrying section.

4. A temperature measurement unit structure according to claim 1, wherein the current-carrying part has a notch on the side opposite to the part where the temperature sensor is arranged, and the notch extends in the direction of current flow.

5. A temperature measuring section structure according to claim 4, wherein the fixing member is made of a metal having the same electrical conductivity as the conductive section.

6. A temperature measurement unit structure according to any one of claims 1 to 5, wherein the current-carrying part on which the temperature sensor is arranged is a coil end of the coil.

7. A temperature measurement unit structure according to any one of claims 1 to 5, wherein the current-carrying part on which the temperature sensor is arranged is a bus bar electrically connected to the coil.

8. A temperature measurement unit structure according to claim 7, wherein the current-carrying unit in which the temperature sensor is disposed is a relay bus bar electrically connected to the neutral point of the Y-connected coil.

9. A temperature measuring unit structure as claimed in claim 1, wherein the fixing device comprises: a main body portion extending in the longitudinal direction of the temperature sensor formed in a rectangular shape; a first extending piece extending from one longitudinal end side of the main body portion to one widthwise side of the main body portion; a second extending piece extending from the one longitudinal end side to the other widthwise side of the main body portion; a third extending piece extending from the other longitudinal end side of the main body portion to one widthwise side; and a fourth extending piece extending from the other longitudinal end side to the other widthwise side, wherein the first extending piece and the third extending piece constitute the first welded fixing part, and the second extending piece and the fourth extending piece constitute the second welded fixing part.

10. A temperature measuring unit structure as claimed in claim 1, wherein the fixing device comprises: a main body portion extending in the longitudinal direction of the temperature sensor formed in a rectangular shape; a first extending piece extending from one longitudinal end side of the main body portion to one widthwise side of the main body portion; a second extending piece extending from the one longitudinal end side to the other widthwise side of the main body portion; a third extending piece extending from the other longitudinal end side of the main body portion to one widthwise side; and a fourth extending piece extending from the other longitudinal end side to the other widthwise side, wherein the third extending piece and the fourth extending piece constitute the first welded fixing part, and the first extending piece and the second extending piece constitute the second welded fixing part.

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