Temperature sensor and method for manufacturing the same

Abstract

To provide a temperature sensor in which a thermistor is accurately determined to a case.SOLUTION: A temperature sensor 100 includes: a thermistor assembly 110; a fixation member 120 to which the thermistor assembly 110 is fixed; a case 130 having a storage region CA for storing the thermistor assembly 110; and a second sealing member 140 arranged in the storage region CA to seal the thermistor assembly 110. The fixation member 120 and the case 130 have guide parts 123 and 132 for determining the position of the fixation member 120 to the bottom part CA.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a temperature sensor and a method for manufacturing the same. [Background technology]

[0002] Patent Document 1 discloses a temperature sensor using a thermistor. In this temperature sensor, a thermistor (temperature-sensing element 4a) connected to a lead wire 5 is sealed with sealing glass (sealing glass portion 4b), and this sealing glass is further sealed with sealing resin (resin coat portion 4c). A thermistor assembly including the thermistor and lead wire 5 is inserted into a case (insertion hole H), and a filling resin (adhesive resin 7) is filled between the thermistor assembly and the case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-128010 Summary of the Invention [Problem to be solved by the invention]

[0004] In such a temperature sensor, the sealing resin is formed by dipping, and the shape and dimensions of the sealing resin are not stable. In such a temperature sensor, it is difficult to accurately position the thermistor relative to the case due to the instability of the shape and dimensions of the sealing resin.

[0005] Furthermore, in such a temperature sensor, the sealing resin may float before the filling resin hardens, causing the position of the thermistor to change relative to the case.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a temperature sensor in which a thermistor is accurately positioned relative to a case. [Means for solving the problem]

[0007] In order to solve the above problem, a temperature sensor according to one embodiment of the present invention comprises a thermistor assembly, a fixing member to which the thermistor assembly is fixed, a case having an accommodating area for accommodating the thermistor assembly, and a second sealing member arranged within the accommodating area so as to seal the thermistor assembly, and the fixing member and the case have guide portions for positioning the fixing member relative to the bottom of the accommodating area.

[0008] A manufacturing method according to one embodiment of the present invention is a manufacturing method for manufacturing a temperature sensor, and includes a fixing step of fixing a thermistor assembly to a fixing member, an injection step of injecting resin into a housing area of ​​a case, an insertion step of inserting the fixing member to which the thermistor assembly is fixed, into the resin injected into the housing area of ​​the case so that the thermistor assembly is sealed by the resin, and a hardening step of hardening the resin. Effect of the Invention

[0009] According to the present invention, it is possible to provide a temperature sensor in which the thermistor is accurately positioned with respect to the case. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 illustrates a temperature sensor 100 according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a front view of the temperature sensor 100. [Diagram 3] 3 is a cross-sectional view of the temperature sensor 100 taken along the line AA in FIG. 2. [Figure 4] 3 is a cross-sectional view of the temperature sensor 100 taken along the line BB in FIG. 2. [Diagram 5] 1 is a perspective view of a fixing member 120 to which a thermistor assembly 110 is fixed. [Figure 6] FIG. 1 is a front view of a fixing member 120 to which a thermistor assembly 110 is fixed. [Figure 7]3A to 3C are diagrams illustrating an example of a method for manufacturing the temperature sensor 100. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Temperature sensor 100> Fig. 1 is a diagram showing a temperature sensor 100 according to one embodiment of the present invention. Fig. 2 is a front view of the temperature sensor 100, Fig. 3 is a cross-sectional view of the temperature sensor 100 taken along line AA in Fig. 2, and Fig. 4 is a cross-sectional view of the temperature sensor 100 taken along line BB in Fig. 2. In Fig. 1, the upward direction is the Z direction (first direction), and two directions perpendicular to the Z direction are the X direction and the Y direction.

[0012] The temperature sensor 100 has a thermistor assembly 110, a fixing member 120, a case 130, and a second sealing member 140. Figures 5 and 6 are diagrams explaining the relationship between the thermistor assembly 110 and the fixing member 120. Figure 5 is a perspective view of the fixing member 120 to which the thermistor assembly 110 is fixed, and Figure 6 is a front view of the fixing member 120 to which the thermistor assembly 110 is fixed.

[0013] The thermistor assembly 110 includes a thermistor 111 , two first lead wires 112 , and a first sealing member 113 .

[0014] The thermistor 111 is a resistor whose resistance value changes depending on temperature, and is, for example, an NTC (Negative Temperature Coefficient) thermistor or a PTC (Positive Temperature Coefficient) thermistor.

[0015] Each of the two first lead wires 112 has a first end 1121 and a second end 1122, and the first end 1121 of the first lead wire 112 is connected to the thermistor 111. That is, the thermistor 111 is connected between the two first lead wires 112, as shown in Fig. 4. The first lead wire 112 extends in a first direction (Z direction) from the first end 1121 connected to the thermistor 111.

[0016] The first lead wire 112 is, for example, a Dumet wire. When the first lead wire 112 is a Dumet wire, the second end 1122 of the first lead wire 112 is connected to the second lead wire 150 as shown in FIGS. 5 and 6. In this case, the second lead wire 150 is composed of, for example, a conductor core wire and an insulating coating covering the core wire. In this case, the core wire of the second lead wire 150 is connected to the first lead wire 112.

[0017] The first sealing member 113 seals and protects the thermistor 111. Of the first lead wire 112, a first end 1121 connected to the thermistor 111 is sealed in the first sealing member 113. A second end 1122 of the first lead wire 112 is not sealed in the first sealing member 113 and exists outside the first sealing member 113. The first sealing member 113 is, for example, glass.

[0018] The fixing member 120 is a member to which the thermistor assembly 110 is fixed. The fixing member 120 is, for example, an insulating material having rigidity, such as a resin.

[0019] The fixing member 120 has fixing portions (first fixing portion 121, second fixing portion 122) as shown in Figures 5 and 6, for example, and the thermistor assembly 110 is fixed to the fixing member 120 by fixing the first lead wire 112 to these fixing portions.

[0020] In the example shown in FIGS. 5 and 6, the fixing member 120 has a first fixing portion 121 and a second fixing portion 122, and the first lead wire 112 has two bent portions (a first bent portion 1123 and a second bent portion 1124). Here, the first bent portion 1123 is a bent portion on the first end portion 1121 side, and the first lead wire 112 is bent at the first bent portion 1123 from a first direction (Z direction) to a second direction (Y direction) or a direction opposite to the second direction (-Y direction). The second bent portion 1224 is a bent portion on the second end portion 1122 side, and the first lead wire 112 is bent at the second bent portion 1124 from a second direction (Y direction) or a direction opposite to the second direction (-Y direction) to the first direction (Z direction). The first fixing portion 121 fixes the first bent portion 1223 of the lead wire 122 , and the second fixing portion 122 fixes the portion of the first lead wire 112 that is close to the first sealing member 113 .

[0021] 5 and 6, it is possible to adjust the position of thermistor 111 relative to fixing member 120 by adjusting the position of first bent portion 1123 of first lead wire 112. Therefore, in this embodiment, it is possible to accurately position thermistor 111 relative to fixing member 120.

[0022] At this time, the thermistor assembly 110 is fixed to the fixing member 120 so that the first sealing member 113 is spaced apart from the fixing member 120, as shown in Figures 5 and 6. That is, the position of the first bent portion 1123 of the first lead wire 112 is adjusted so that the first sealing member 113 is spaced apart from the fixing member 120. The distance between the first sealing member 113 and the fixing member 120 is equal to or less than a first distance. The first distance is appropriately set so that the first lead wire 112 does not bend when the fixing member 120 to which the thermistor assembly 110 is fixed is inserted into the second sealing member 140. The first distance is, for example, 1 mm.

[0023] 3, the case 130 has an accommodation area CA, which is open in the first direction (Z direction) (opening 131). The thermistor assembly 110 and the fixing member 120 are accommodated in the accommodation area CA of the case 130.

[0024] The fixing member 120 and the case 130 have guide portions 123, 132 for positioning the fixing member 120 with respect to the bottom of the accommodation area CA of the case 130. In this case, for example, as shown in Fig. 3, the guide portion 123 of the fixing member 120 has a surface facing the first direction (Z direction), and the guide portion 132 of the case 130 has a surface facing the opposite direction to the first direction (-Z direction), and these surfaces are preferably in contact with each other. The positions of the guide portion 123 of the fixing member 120 and the guide portion 132 of the case 130 are set, for example, as shown in Fig. 3, so that the first sealing member 113 of the thermistor assembly 110 is separated from the bottom of the accommodation area CA of the case 130 when the fixing member 120 to which the thermistor assembly 110 is fixed is accommodated in the case 130. In the example shown in FIG. 3, guide portion 132 of case 130 is an engagement hole, and guide portion 123 of fixing member 120 is an engagement claw that engages with this engagement hole.

[0025] As shown in Figures 3 and 4, the second sealing member 140 is disposed within the housing area CA of the case 130 so as to seal the thermistor assembly 110. Of the second lead wire 150, a first end 151 connected to the first lead wire 112 is sealed in the second sealing member 140. As shown in Figure 1, a second end 152 of the second lead wire 150 is not sealed in the second sealing member 140 and exists outside the second sealing member 140. The second sealing member 140 is, for example, a resin.

[0026] For example, the second sealing member 140 is injected into the housing area CA of the case 130 before being cured. Then, the thermistor assembly 110 is inserted into the second sealing member 140 injected into the housing area CA of the case 130 so that the first sealing member 113 is sealed by the second sealing member 140. Then, the second sealing member 140 is cured in a state in which the first resin part 113 is sealed.

[0027] In this manner, in this embodiment, it is possible to accurately position the thermistor 111 with respect to the fixing member 120, and it is possible to accurately position the fixing member 120 with respect to the case 130. As a result, in this embodiment, it is possible to accurately position the thermistor 111 with respect to the case 130.

[0028] Furthermore, in this embodiment, the guide portion 123 of the fixing member 120 has a surface facing the first direction (Z direction), and the guide portion 132 of the case 130 has a surface facing the opposite direction to the first direction (-Z direction), and these surfaces are in contact with each other. For this reason, in this embodiment, it is possible to prevent the fixing member 120 from floating before the second sealing member 140 hardens, that is, to prevent the thermistor assembly 110 from floating. As a result, in this embodiment, it is possible to provide a temperature sensor in which the thermistor is accurately positioned with respect to the case.

[0029] Moreover, in this embodiment, there is no need to further seal the first sealing member 113 by dipping. Therefore, in this embodiment, it is possible to omit the dipping process (including degassing and hardening of the dipping resin), and it is possible to reduce the manufacturing cost.

[0030] The temperature sensor 100 may further include a connection member 160. The connection member 160 is a member for connecting the temperature sensor 100 to an object to be measured. In this case, the case 130 has an insertion opening 133 for inserting the connection member 160, and the connection member 160 is inserted into the insertion opening 133.

[0031] The connection member 160 is, for example, a member with high thermal conductivity. When the connection member 160 is connected to the measurement object, the connection member 160 has the same temperature as the measurement object. Furthermore, the connection member 160 is a conductor. If the measurement object is a conductor through which a current flows, when the connection member 160 is connected to the measurement object, the current flowing through the measurement object flows through the connection member 160, and the connection member 160 has the same temperature as the measurement object.

[0032] The connection member 160 has, for example, a hole 161. At this time, the connection member 160 is inserted into the insertion opening 133 of the case 130 so that the thermistor 111 is located inside the hole 161. In this way, the thermistor 111 is surrounded by the connection member 160, and it becomes possible to accurately measure the temperature of the connection member 160 (i.e., the temperature of the measurement target) without being affected by the temperatures of other members. The hole 161 is, for example, a through hole.

[0033] 1 and 3, the temperature sensor 100 may further include a cover 170 that covers the opening 131 of the housing area CA of the case 130. The cover 170 is fixed to the case 130 in a state in which the cover 170 covers the opening 131 of the housing area CA of the case 130. The cover 170 contacts the fixing member 120 from the first direction (Z direction) as shown in Fig. 3. This makes it possible to more effectively prevent the fixing member 120 from floating before the second sealing member 140 hardens.

[0034] <Method of Manufacturing Temperature Sensor 100> FIG. 7 is a diagram showing an example of a method for manufacturing the temperature sensor 100.

[0035] First, the thermistor assembly 110 is fixed to the fixing member 120 (fixing step, step S701). At this time, the first sealing member 113 of the thermistor 110 is positioned relative to the fixing member 120 (that is, the thermistor 111 sealed in the first sealing member 113 is positioned).

[0036] Next, resin is injected into the housing area CA of the case 130 (injection step, step S702). The injected resin is the resin of the second sealing member 140 before it hardens.

[0037] Then, the fixing member 120 to which thermistor assembly 110 is fixed is inserted into the resin injected into the housing area CA of the case 130 so that the thermistor assembly 110 is sealed by the resin (insertion step, step S703). At this time, for example, the fixing member 120 is inserted so that the engagement claw (guide portion 123) of the fixing member 120 engages with the engagement hole (guide portion 132) of the case 130. This positions the fixing member 120 relative to the case 130, and as a result, the thermistor 111 positioned in the fixing member 120 is positioned relative to the case 130.

[0038] Thereafter, the opening 131 of the accommodation area CA of the case 130 is closed so that the cover 170 contacts the fixing member 120 from the first direction (closing step, step 704).

[0039] Finally, the resin injected into the housing area CA of the case 130 is cured (curing step, step S705). As a result, the resin injected into the housing area CA of the case 130 is cured, and the second sealing member 140 is disposed in the housing area CA of the case 130 so as to seal the thermistor assembly 110, and the temperature sensor 100 is completed.

[0040] The present invention has been described above in terms of preferred embodiments thereof. Although the present invention has been described herein with reference to specific examples, various modifications and variations can be made to these examples without departing from the spirit and scope of the present invention as set forth in the claims. [Explanation of symbols]

[0041] 100 Temperature Sensor 110 Thermistor assembly 111 Thermistor of the thermistor assembly 100 112 First lead wire of thermistor assembly 100 1121 First end of the first lead wire 112 1122 Second end of first lead wire 112 1123 First bent portion of first lead wire 112 1124: second bent portion of first lead wire 112 113 First sealing member of thermistor assembly 100 120 Fixing member 121 First fixing portion of fixing portion 120 122 Second fixing portion of fixing portion 120 123 Guide portion (engagement claw) of fixed portion 120 130 cases 131 Opening of case 130 132 Guide portion (engagement hole) of case 130 133 Insertion port of case 130 140 Second sealing member 150 Second Lead 151 First end of second lead wire 150 152 Second end of second lead wire 150 160 Connection parts 161 Hole of connecting member 160 170 Cover

Claims

1. a thermistor assembly; a fixing member to which the thermistor assembly is fixed; a case having a housing area for housing the thermistor assembly; a second sealing member disposed within the receiving area to seal the thermistor assembly; A temperature sensor, wherein the fixing member and the case have a guide portion for positioning the fixing member relative to the bottom of the storage area.

2. The thermistor assembly includes: Two first leads; a thermistor connected to first ends of the two first leads; The temperature sensor according to claim 1 , further comprising: a first sealing member that seals the thermistor.

3. Further comprising two second leads; a first end of each of the two second leads is connected to a second end of a corresponding one of the first leads; The temperature sensor of claim 2 , wherein the first lead wire is a Dumet wire.

4. The temperature sensor according to claim 2 , wherein the fixing member has a fixing portion for fixing the first lead wire.

5. the first lead wire has a first bent portion, The temperature sensor according to claim 4 , wherein the fixing portion fixes the first bent portion.

6. a position of the first bent portion of the first lead wire is adjusted so that the first sealing member is spaced apart from the fixing member; The temperature sensor of claim 5 , wherein a distance between the first sealing member and the fixing member is less than or equal to a first distance.

7. Further comprising a connection member for connecting to the measurement object, The connecting member has a hole, the case has an insertion opening into which the connection member is inserted, The temperature sensor according to claim 4 , wherein the connection member is inserted into an insertion opening of the case so that the thermistor is located within the hole.

8. The temperature sensor according to claim 7 , wherein the connecting member is a conductor.

9. Further comprising a cover; The housing area of ​​the case is open in a first direction, The temperature sensor according to claim 1 , wherein the cover is disposed so as to be in contact with the fixing member from the first direction.

10. A manufacturing method for manufacturing a temperature sensor, comprising: a fixing step of fixing the thermistor assembly to a fixing member; an injection step of injecting resin into the housing area of ​​the case; an inserting step of inserting the fixing member to which the thermistor assembly is fixed into resin injected into the housing area of ​​the case so that the thermistor assembly is sealed by the resin; and a curing step of curing the resin.

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