Temperature sensor for bus bar, bus bar module, and method for manufacturing same

Abstract

The invention provides a temperature sensor for a bus bar, a bus bar module and a manufacturing method thereof, wherein the temperature sensor and the bus bar module can reliably and closely contact a heated surface to measure the temperature of the bus bar with high precision. A temperature sensor (1) for a bus bar according to the present invention is used by being attached to a bus bar (2), and is provided with: a heat-sensitive element (3); and a housing part (4) in which the heat-sensitive element is housed, the bus bar having a through-hole (2a), the housing part having: a housing main body (5); and a protruding part (6) which is formed by protruding from the housing main body and can be inserted into the through hole, and which accommodates the heat-sensitive element.

Description

Technical Field

[0001] The present invention relates to a bus bar temperature sensor and a bus bar module mounted on a bus bar used as a wiring member of a motor stator or a battery, and a method for manufacturing the same. Background Art

[0002] A bus bar used as a wiring member for a motor stator or a battery, etc., is known to have a temperature sensor mounted thereon to detect the temperature of the bus bar. For example, since the motor stator can become high temperature, control using the temperature sensor is necessary.

[0003] Conventionally, for example, Patent Document 1 describes a temperature detection device using a metal bracket in which a temperature sensor is mounted on a coil.

[0004] Patent Document 2 describes a stator of a rotating electric machine including: a neutral line having a U-shaped portion connected to a stator coil and bent into a U-shape; and a temperature sensor in contact with the neutral line.

[0005] Patent Document 1: Japanese Patent No. 6674070

[0006] Patent Document 2: Japanese Patent Publication No. 2018-61389

[0007] The above-mentioned prior art still has the following problems.

[0008] That is, in the above-mentioned prior art, there is a tolerance in the mounting frame such as a bracket or a rectangular line such as a neutral line, so there is a problem that when the temperature sensor is mounted, it shakes, and the heating surface of the temperature sensor is not reliably in close contact, resulting in a decrease in the accuracy of temperature measurement. In addition, when insulating varnish is used as a fixing method, if a deviation occurs when the insulating varnish enters between the mounting frame or the rectangular line and the heating surface of the temperature sensor, there is still a problem that the heat receiving property is affected. Summary of the invention

[0009] The present invention has been made in view of the above problems, and an object of the present invention is to provide a bus bar temperature sensor and a bus bar module and a method for manufacturing the same, which can measure the temperature of the bus bar with high accuracy by making the heat receiving surface reliably in close contact.

[0010] In order to solve the above problems, the present invention adopts the following structure. That is, the busbar temperature sensor involved in the first invention is a temperature sensor mounted on a busbar for use, characterized in that it comprises: a thermistor; and a housing portion, which accommodates the thermistor, wherein the busbar has a through hole, and the housing portion comprises: a housing body; and a protrusion, which is formed to protrude from the housing body and can be inserted into the through hole, and the thermistor is accommodated in the protrusion.

[0011] In this busbar temperature sensor, since there is a protrusion formed from the shell body and can be inserted into the through hole, and a thermistor is accommodated in the protrusion, the protrusion inserted into the through hole can receive the heat of the busbar from the entire circumference, thereby improving thermal responsiveness and enabling high-precision temperature measurement.

[0012] The bus bar temperature sensor according to the second invention is characterized in that, in the first invention, the end surface of the case body where the protrusion is formed is in contact with or close to the bus bar when the protrusion is inserted into the through hole.

[0013] That is, in the busbar temperature sensor, since the end face of the protrusion formed in the shell body is in a state of abutting or being close to the busbar when the protrusion is inserted into the through hole, the end face of the shell body becomes a stopper when the protrusion is inserted, and the end face can also receive heat from the busbar.

[0014] The busbar temperature sensor involved in the third invention is characterized in that, in the first invention, it comprises: a pair of leads, which are accommodated in the shell body and one end of which is connected to the thermistor; and a pair of electrode terminals, which are accommodated in the shell body and one end of which is connected to the other end of the pair of leads, and the shell body has a connector part, and the other end of the pair of electrode terminals and the pair of external wirings can be connected by inserting a pair of external wirings into the connector part.

[0015] That is, in this bus bar temperature sensor, since the case body has the connector portion, the other ends of the pair of electrode terminals and the pair of external wires can be connected by inserting the pair of external wires into the connector portion, and thus the external wires can be easily connected through the connector portion.

[0016] The bus bar module involved in the fourth invention is characterized in that it comprises: a bus bar; a bus bar temperature sensor according to any one of the first to third inventions, which is mounted on the bus bar; and a resin molded part, which fills the gap between the through hole and the protrusion and seals the through hole and the protrusion.

[0017] That is, in this bus bar module, since there is a resin molded part that fills the gap between the through hole and the protrusion and seals the through hole and the protrusion, the through hole and the protrusion are in contact directly or via the resin molded part, so that the heat receiving surface is in close contact over the entire circumference, thereby increasing the contact area between the bus bar and the protrusion and improving thermal responsiveness.

[0018] A bus bar module according to a fifth aspect of the present invention is characterized in that, in the fourth aspect, the bus bar has a wide portion that expands in a width direction around the through hole, and the resin molded portion also seals the wide portion.

[0019] That is, in the bus bar module, since the bus bar has a wide portion that expands in the width direction around the through hole, the strength around the through hole can be reinforced by the wide portion. In addition, since the resin molded portion also seals the wide portion, heat from the wide portion can be transferred to the bus bar temperature sensor via the resin molded portion, and the temperature can be measured with higher accuracy.

[0020] A bus bar module according to a sixth aspect of the present invention is characterized in that, in the fourth aspect, the through hole and the protrusion both have circular cross sections.

[0021] That is, in this bus bar module, since the cross sections of the through hole and the protrusion are both circular, it is easy to uniformly fill the gap between the through hole and the protrusion with resin over the entire circumference, and it is easy to uniformly transfer heat from the entire circumference to the protrusion.

[0022] A bus bar module according to a seventh aspect of the present invention is characterized in that, in any one of the fourth to sixth aspects of the present invention, the bus bar is used for a motor stator.

[0023] That is, in this bus bar module, since the bus bar is used for the motor stator, the temperature of the motor stator can be measured accurately and stably by the protruding portion of the temperature sensor whose heat receiving surface is reliably in close contact.

[0024] The manufacturing method of the bus bar module involved in the eighth invention is a method for manufacturing the bus bar module of the fourth invention, characterized in that it includes: a protrusion insertion process, inserting the protrusion of the bus bar temperature sensor of any one of the first to third inventions into a through hole formed in the bus bar; and a resin filling process, filling resin into the gap between the through hole and the protrusion, and forming a resin molding part that seals the through hole and the protrusion.

[0025] According to the present invention, the following effects are achieved.

[0026] That is, according to the busbar temperature sensor involved in the present invention, since it has a protrusion formed from the shell body and can be inserted into the through hole, and the protrusion accommodates a thermistor, the protrusion inserted into the through hole can receive the heat of the busbar from the entire circumference, thereby improving thermal responsiveness and enabling high-precision temperature measurement.

[0027] Furthermore, according to the bus bar module and its manufacturing method involved in the present invention, since it has a resin molded part that fills the gap between the through hole and the protrusion and seals the through hole and the protrusion, the through hole is in contact with the protrusion directly or via the resin molded part, so that the heat receiving surface is in close contact over the entire circumference, thereby increasing the contact area between the bus bar and the protrusion and improving thermal responsiveness.

[0028] As described above, in the bus bar temperature sensor and the bus bar module and the method for manufacturing the same according to the present invention, the thermal responsiveness is accelerated, and thus they are suitable for high-precision temperature measurement of a bus bar such as a motor stator. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1A This is a perspective view showing a bus bar temperature sensor, a bus bar module, and a method for manufacturing the same according to a first embodiment of the present invention before a protruding portion is inserted.

[0030] Figure 1B This is a perspective view showing a bus bar temperature sensor, a bus bar module, and a method for manufacturing the same according to the first embodiment of the present invention after a protruding portion is inserted.

[0031] Figure 1C This is a perspective view showing a bus bar temperature sensor and a bus bar module and a method for manufacturing the same according to the first embodiment of the present invention after a resin molded portion is formed.

[0032] Figure 2 It is a longitudinal sectional view showing the bus bar temperature sensor and the bus bar module above the connector portion in the first embodiment.

[0033] Figure 3A It is a side view showing the bus bar module in the first embodiment.

[0034] Figure 3B It is a cross-sectional view taken along the line AA showing the bus bar module in the first embodiment.

[0035] Figure 4A It is a side view showing a bus bar module in a second embodiment of the bus bar temperature sensor, the bus bar module, and the method for manufacturing the same according to the present invention.

[0036] Figure 4B BB is a cross-sectional view of a bus bar module in a second embodiment of a bus bar temperature sensor, a bus bar module, and a method for manufacturing the same according to the present invention.

[0037] Figure 5 This is a perspective view of a bus bar module showing the inside thereof through a see-through view in a third embodiment of a bus bar temperature sensor, a bus bar module, and a method for manufacturing the same according to the present invention.

[0038] Figure 6 It is a perspective view showing a bus bar module according to the third embodiment. DETAILED DESCRIPTION

[0039] Below, reference Figures 1A to 3B , a first embodiment of a busbar temperature sensor and a busbar module and a method for manufacturing the same according to the present invention is described. In addition, in some of the drawings used in the following description, the scale is appropriately changed as needed to make each part a recognizable or easily recognizable size.

[0040] like Figures 1A to 3B As shown, the bus bar temperature sensor 1 of the present embodiment is a temperature sensor that is mounted on a bus bar 2 and used, and includes a thermosensitive element 3 and a housing 4 that accommodates the thermosensitive element 3 therein.

[0041] The bus bar 2 has a through hole 2 a.

[0042] The case portion 4 includes a case body 5 and a protrusion 6 formed to protrude from the case body 5 and insertable into the through hole 2 a .

[0043] In addition, the case portion 4 is molded from resin.

[0044] like Figure 2 As shown, the protrusion 6 contains the thermal element 3 .

[0045] The end surface 5 a of the case body 5 where the protrusion 6 is formed is in contact with or close to the bus bar 2 when the protrusion 6 is inserted into the through hole 2 a .

[0046] And, if Figure 2 As shown, the bus bar temperature sensor 1 of the present embodiment includes a pair of lead wires 3 a which are accommodated in a case body 5 and one end of which is connected to the temperature sensitive element 3 .

[0047] The case body 5 has an insertion port 8 c into which a pair of external wirings L are inserted.

[0048] The insertion port 8 c is formed by separately fitting an insertion port lower portion 8 b formed of resin into an insertion port upper portion 8 a formed at the lower portion of the housing body 5 .

[0049] Furthermore, the insertion port 8 c opens in a direction perpendicular to the protruding direction of the protruding portion 6 .

[0050] The bus bar module 10 of the present embodiment includes: the bus bar 2 ; the bus bar temperature sensor 1 mounted on the bus bar 2 ; and a resin molded portion 11 filling a gap between the through hole 2 a and the protrusion 6 and sealing the through hole 2 a and the protrusion 6 .

[0051] The bus bar 2 has a wide portion 2 b that expands in the width direction around the through hole 2 a.

[0052] like Figure 1B and Figure 2 As shown, the wide portion 2b has a shape that expands in an arc shape along the width direction corresponding to the through hole 2a having a circular cross section.

[0053] The resin molded portion 11 also seals the wide portion 2 b. That is, the resin molded portion 11 is formed from the upper surface of the bus bar 2 to the lower surface of the bus bar 2 so as to cover the wide portion 2 b.

[0054] The through hole 2a and the protrusion 6 both have circular cross sections.

[0055] The bus bar 2 is used in a motor stator. That is, the bus bar temperature sensor 1 of the present embodiment is used to detect the temperature of the coil conductor of the motor stator.

[0056] Furthermore, the bus bar 2 is formed of metal such as Cu.

[0057] The bus bar module 10 of the present embodiment is mounted on the coil portion of the motor by welding or the like.

[0058] like Figure 2 As shown, the heat sensitive element 3 includes a sealing glass portion (not shown) covering a thermistor (not shown) mounted on a substrate (not shown) with glass, and a resin coating portion 3b covering the sealing glass portion with resin.

[0059] Furthermore, a pair of lead wires 3 a are connected to the temperature-sensitive element 3 , and a pair of external wirings L are connected to the pair of lead wires 3 a via connection terminal portions 7 a (riveting terminals).

[0060] The casing 4 is filled with an insulating resin 9. The insulating resin 9 may be an insulating resin such as a silicone resin or an epoxy resin, and a resin having good thermal conductivity is particularly preferred.

[0061] The manufacturing method of the busbar module of this embodiment includes: a protrusion inserting step, such as Figure 1A and Figure 1B As shown, the protrusion 6 of the busbar temperature sensor 1 is inserted into the through hole 2a formed in the busbar 2; and the resin filling step, as shown Figure 1C and Figure 2 As shown, a resin is filled into a gap between the through hole 2 a and the protruding portion 6 , and a resin molded portion 11 that seals the through hole 2 a and the protruding portion 6 is formed.

[0062] In the resin filling step, the resin is filled into the gap between the through hole 2 a and the protrusion 6 by insert molding, and the resin molded portion 11 that seals the wide portion 2 b , the through hole 2 a , and the protrusion 6 is formed.

[0063] In this way, the busbar temperature sensor 1 of the present embodiment has a protrusion 6 protruding from the shell body 5 and capable of being inserted into the through hole 2a, and the protrusion 6 accommodates the thermistor 3. Therefore, the protrusion 6 inserted into the through hole 2a can receive the heat of the busbar 2 from the entire periphery, thereby improving the thermal responsiveness and enabling high-precision temperature measurement.

[0064] Furthermore, since the end face 5a of the protrusion 6 formed in the shell body 5 is in a state of abutting or being close to the busbar 2 when the protrusion 6 is inserted into the through hole 2a, the end face 5a of the shell body 5 becomes a stopper when the protrusion 6 is inserted, and the end face 5a can also receive heat from the busbar 2.

[0065] In the bus bar module 10 of the present embodiment, since it is provided with a resin molded portion 11 that fills the gap between the through hole 2a and the protrusion 6 and seals the through hole 2a and the protrusion 6, the through hole 2a is in contact with the protrusion 6 directly or via the resin molded portion 11, so that the heat receiving surface is in close contact over the entire circumference, thereby increasing the contact area between the bus bar 2 and the protrusion 6 and improving thermal responsiveness.

[0066] Furthermore, since the bus bar 2 has the wide portion 2 b that expands in the width direction around the through hole 2 a , the strength around the through hole 2 a can be reinforced by the wide portion 2 b .

[0067] That is, when the wide portion 2b is not provided, the strength of the bus bar 2 around the through hole 2a is reduced due to the formation of the through hole 2a, but by providing the wide portion 2b, the periphery of the through hole 2a becomes wider, thereby improving the strength and strengthening the bus bar 2. In addition, by providing the wide portion 2b, the inner diameter of the through hole 2a can be increased, and the contact area with the protrusion 6 can be increased compared to the case where the wide portion 2b is not provided.

[0068] Furthermore, since the resin molded portion 11 also seals the wide portion 2 b , heat from the wide portion 2 b can be transferred to the bus bar temperature sensor 1 via the resin molded portion 11 , and the temperature can be measured with higher accuracy.

[0069] Furthermore, since the cross sections of the through hole 2a and the protrusion 6 are both circular, the gap between the through hole 2a and the protrusion 6 can be easily filled with resin uniformly over the entire circumference, and heat can be easily uniformly transferred from the entire circumference to the protrusion.

[0070] Furthermore, since the bus bar 2 is used for the motor stator, the temperature of the motor stator can be measured with high accuracy and stability by the protrusion 6 of the temperature sensor 1 whose heat receiving surface is reliably in close contact.

[0071] Next, the following reference FIG. 4A to FIG. 6 , the second and third embodiments of the busbar temperature sensor and busbar module and the manufacturing method thereof according to the present invention are described. In the following description of the embodiments, the same components as those described in the above embodiments are denoted by the same reference numerals and their description is omitted.

[0072] The second embodiment is different from the first embodiment in that, in the first embodiment, the cross section of the through hole 2a is circular, whereas in the bus bar temperature sensor 1 and the bus bar module 20 of the second embodiment, Figure 4B As shown, the cross section of the through hole 22a is substantially square.

[0073] Furthermore, in the second embodiment, the wide portion 22b has a substantially trapezoidal shape corresponding to the through hole 22a having a substantially square cross section.

[0074] Next, the third embodiment is different from the second embodiment in that, in the second embodiment, the housing portion 4 is composed of a plurality of components such as a housing body 5 (connector upper portion or connector lower portion, etc.) and a protruding portion 6, whereas, in the bus bar temperature sensor 31 and the bus bar module 30 of the third embodiment, as shown in FIG. Figure 5 and Figure 6 As shown, the housing portion 34 is also different in that it is produced by integrally molding with resin.

[0075] That is, in the third embodiment, the case portion 34 is manufactured by insert molding in a state where the temperature-sensitive element 33 , the pair of lead wires 33 a , and the pair of electrode terminals 37 are housed.

[0076] Furthermore, the bus bar temperature sensor 31 of the third embodiment includes a pair of electrode terminals 37 which are accommodated in the case body 35 and one end of which is connected to the other end of the pair of lead wires 3 a .

[0077] Furthermore, the case body 35 has a connector portion 38 into which the other ends of the pair of electrode terminals 37 and the pair of external wirings can be connected by inserting the pair of external wirings.

[0078] The connector portion 38 can be connected to the other ends of the pair of electrode terminals 37 exposed in the connector portion 38 by inserting the front ends of the pair of external wirings into the insertion port 8 c .

[0079] As described above, in the third embodiment, since the case portion 34 is manufactured by integral molding, the number of components can be reduced, and the assembly cost can also be reduced.

[0080] Furthermore, since the case body 35 has the connector portion 38 , the other ends of the pair of electrode terminals 37 and the pair of external wires can be connected by inserting the pair of external wires into the connector portion 38 , and thus the external wires can be easily connected via the connector portion 38 .

[0081] In the second embodiment, the thermosensitive element 3 is vertically long and a pair of leads 3a protrude from the lower portion of the thermosensitive element 3 . In the third embodiment, the thermosensitive element 33 is horizontally long and a pair of leads 33a protrude from both ends of the thermosensitive element 3 .

[0082] Furthermore, in the third embodiment, the cross sections of the through hole 32 a and the protrusion 36 are both formed in a rectangular shape corresponding to the shape of the temperature-sensitive element 33 .

[0083] Example

[0084] Regarding the bus bar temperature sensor and the bus bar module according to the first embodiment and the second embodiment, a thermal time constant of the bus bar temperature sensor when the bus bar temperature is instantaneously raised to 150° C. was simulated.

[0085] Furthermore, a simulation was also performed similarly as a conventional example regarding a case where only a temperature sensor containing a thermosensitive element in a rectangular resin molded portion used in Patent Document 1 or Patent Document 2 was mounted on the surface of a bus bar.

[0086] As a result, in the above-mentioned conventional example, the thermal time constant was 18.2 seconds, while it was 6.0 seconds in the bus bar temperature sensor and bus bar module of the second embodiment using a through hole with a rectangular cross-section, and it was 4.6 seconds in the bus bar temperature sensor and bus bar module of the first embodiment using a through hole with a circular cross-section.

[0087] As described above, the bus bar temperature sensor and the bus bar module according to the first and second embodiments of the present invention have a shorter thermal time constant than the conventional examples, and can be greatly increased in speed.

[0088] In addition, the technical scope of the present invention is not limited to the above-mentioned embodiments and examples, and various modifications can be added within the scope not departing from the spirit of the present invention.

[0089] For example, in the above embodiments, thermistors are used, but thermistors may be chip thermistors, sheet thermistors, or thin film thermistors, and thermoelectric elements may also be used. In particular, thermistors with a heat resistance of 200° C. are preferred.

[0090] Furthermore, as in the above-mentioned embodiments, the bus bar temperature sensor is preferably sealed with a resin molded portion and fixed to the bus bar, but the bus bar temperature sensor may be fixed to the bus bar with an insulating varnish or the like.

[0091] Explanation of symbols

[0092] 1.31 Busbar temperature sensor

[0093] 2 Busbar

[0094] 2a, 22a, 32a through holes

[0095] 2b wide section

[0096] 3.33 Thermistor

[0097] 3a, 33a lead

[0098] 4.34 Shell

[0099] 5.35 Shell body

[0100] 5a The end surface of the housing body on which the protrusion is formed

[0101] 6 Protrusion

[0102] 7 Electrode terminal

[0103] 8, 38 connector part

[0104] 10, 20 busbar modules

[0105] 11 Resin molding department

[0106] L External wiring

Claims

1. A busbar temperature sensor, which is a temperature sensor mounted on a busbar for use, characterized in that: have: Thermal sensors; and The housing contains the thermal element. The bus bar has a through hole, The housing portion has: a housing body; and a protrusion formed to protrude from the housing body and capable of being inserted into the through hole, The thermal element is accommodated in the protruding portion.

2. The bus bar temperature sensor according to claim 1, characterized in that: The end surface of the case body where the protrusion is formed is in contact with or close to the bus bar when the protrusion is inserted into the through hole.

3. The bus bar temperature sensor according to claim 1, wherein: have: a pair of leads, housed in the housing body and one end of which is connected to the thermal element; and a pair of electrode terminals, which are accommodated in the housing body and one end of which is connected to the other end of the pair of lead wires, The case body has a connector portion into which the other ends of the pair of electrode terminals and the pair of external wirings can be connected by inserting the pair of external wirings into the connector portion.

4. A busbar module, characterized in that: have: Busbars; The busbar temperature sensor according to claim 1, mounted on the busbar; and The resin molded portion fills a gap between the through hole and the protruding portion and seals the through hole and the protruding portion.

5. The busbar module according to claim 4, characterized in that: The bus bar has a wide portion that expands in the width direction around the through hole. The resin molded portion also seals the wide width portion.

6. The busbar module according to claim 4, characterized in that: The cross sections of the through hole and the protrusion are both circular.

7. The bus bar module according to claim 4, characterized in that: The busbars are used in a motor stator.

8. A method for manufacturing a busbar module, which is a method for manufacturing the busbar module according to claim 4, characterized in that: include: a protrusion inserting step of inserting the protrusion of the busbar temperature sensor according to claim 1 into a through hole formed in the busbar; and The resin filling step fills a gap between the through hole and the protrusion with resin, thereby forming a resin molded portion that seals the through hole and the protrusion.

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