Thermistor assembly, temperature sensor, and method of manufacturing same

Abstract

To provide a temperature sensor in which a thermistor is accurately determined with respect to a case.SOLUTION: A thermistor assembly body 110 includes a thermistor 111, rigid two lead members 112, and a first resin part 113. A first end part 1121 of the two lead members 112 is connected to the thermistor 111 and the thermistor 111 is sealed by the first resin part 113.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] One method for manufacturing a temperature sensor using a thermistor is to inject a filling resin into a protective case and then insert a thermistor assembly including a thermistor and lead wires into the filling resin in the protective case.

[0003] A thermistor assembly in which the thermistor is glass-sealed is known (for example, Patent Document 1). In the thermistor assembly in which the thermistor is glass-sealed, a dumet wire, which has a thermal expansion coefficient close to that of glass, is used as the lead wire. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6405074 Summary of the Invention [Problem to be solved by the invention]

[0005] Dumet wire is soft and can bend when the thermistor assembly is inserted into the filled resin, making it difficult to accurately position it relative to the thermistor's protective case.

[0006] Therefore, a method has been proposed in which rigid lead wires are further connected to the dumet wire, and the glass that encapsulates the thermistor and the dumet wire are sealed with sealing resin, after which the thermistor assembly is inserted into the filled resin. The sealing resin is formed by dipping, and the shape and dimensions of the sealing resin are unstable. In this case, the lead wires do not bend, but the unstable shape and dimensions of the sealing resin make it difficult to accurately position the thermistor in the protective case.

[0007] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a temperature sensor in which a thermistor is accurately positioned relative to a case. [Means for solving the problem]

[0008] In order to solve the above problem, a thermistor assembly according to one embodiment of the present invention comprises a thermistor, two rigid lead members, and a first resin part, wherein first ends of the two lead members are connected to the thermistor, and the thermistor is sealed by the first resin part.

[0009] A temperature sensor according to one embodiment of the present invention comprises the above-described thermistor assembly, a case having a storage area that is open in a first direction, and a second resin part, the second resin part being positioned within the storage area so as to seal the first resin part.

[0010] A manufacturing method for manufacturing a thermistor assembly according to one embodiment of the present invention includes a connecting step of connecting a thermistor to first ends of two rigid lead members, and a molding step of molding the first resin portion by transfer molding so that the thermistor is sealed by the first resin portion.

[0011] A manufacturing method according to one embodiment of the present invention is a manufacturing method for manufacturing a temperature sensor, and includes a connecting step of connecting a thermistor to first ends of two rigid lead members; a molding step of molding the first resin portion by transfer molding so that the thermistor is sealed by the first resin portion; an injection step of injecting resin into a housing area of ​​a case; an insertion step of inserting the thermistor assembly into the resin so that the first resin portion is sealed by the resin injected into the housing area of ​​the case; and a curing step of curing the resin. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a temperature sensor in which the thermistor is accurately positioned relative to the case. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing a temperature sensor 100 according to an embodiment of the present invention. [Figure 2] FIG. 2 is a front view of the temperature sensor 100. [Figure 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. [Figure 5] 3 is a cross-sectional view of the temperature sensor 100 taken along the CC cross section of FIG. 2. [Figure 6] FIG. 1 shows a thermistor assembly 110. [Figure 7] 1 is a diagram illustrating the relationship between a thermistor 111 and two lead members 112. FIG. [Figure 8] 10A and 10B are diagrams showing another example of the thermistor assembly 110. FIG. [Figure 9] 10 is a diagram illustrating the relationship between the lead member 112 and the second resin portion 130. FIG. [Figure 10] 3A to 3C are diagrams illustrating an example of a method for manufacturing the temperature sensor 100. DETAILED DESCRIPTION OF THE INVENTION

[0014] <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, Fig. 4 is a cross-sectional view of the temperature sensor 100 taken along line BB in Fig. 2, and Fig. 5 is a cross-sectional view of the temperature sensor 100 taken along line CC 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.

[0015] The temperature sensor 100 includes a thermistor assembly 110, a case 120, and a second resin portion .

[0016] 6 is a diagram showing the thermistor assembly 110. The thermistor assembly 110 has a thermistor 111, two lead members 112, and a first resin portion 113.

[0017] The thermistor 111 is a resistor whose resistance value changes depending on the temperature, and is, for example, an NTC (Negative Temperature Coefficient) thermistor or a PTC (Positive Temperature Coefficient) thermistor. The thermistor 111 is, for example, a chip-type thermistor.

[0018] Each of the two lead members 112 has a first end 1121 and a second end 1122, and the first end 1121 of the lead member 112 is connected to the thermistor 111. That is, the thermistor 111 is connected between the two first lead members 112, as shown in Fig. 7. Fig. 7 is a diagram for explaining the relationship between the thermistor 111 and the two lead members 112, and only the thermistor 111 and the two lead members 112 are shown in Fig. 7.

[0019] The first end 1121 of the lead member 112 is connected to the thermistor 111 by, for example, welding or soldering. The lead member 112 extends in a first direction (Z direction) from the first end 1121 connected to the thermistor 111.

[0020] The lead member 112 has rigidity, i.e., high rigidity, and is, for example, a metal plate (e.g., a lead frame) as shown in FIGS. 3, 6, and 7. The lead member 112 may be a metal rod, or may include both a metal plate portion and a metal rod portion. The thickness of the metal plate is preferably equal to or greater than a first thickness, and the diameter of the metal rod is preferably equal to or greater than a first radius. The first thickness and the first radius are appropriately set so that the thermistor assembly 110 does not bend when the thermistor assembly 110 is inserted into the second resin part 130.

[0021] 4 and 6, the first resin portion 113 seals and protects the thermistor 111. A first end 1121 of the lead member 112 connected to the thermistor 111 is sealed in the first sealing member 113, as shown in FIGS. 4 and 6. A second end 1122 of the lead member 112 is not sealed in the first resin portion 113, and is located outside the first resin portion 113, as shown in FIG.

[0022] First resin portion 113 is made of resin and is molded by transfer molding. That is, the thermistor assembly 110 is manufactured by placing thermistor 111 connected to lead members 111 in a cavity of a mold, then pressing heated and softened resin into the cavity, and then hardening the resin pressed into the cavity.

[0023] As described above, in this embodiment, first resin portion 113 has high rigidity because it is formed by transfer molding. Furthermore, in this embodiment, lead member 112 also has rigidity, and thermistor assembly 110 as a whole has rigidity.

[0024] The second end 1122 of the lead member 112 is connected to a lead wire 140, for example, as shown in Fig. 6. The second end 1122 of the lead member 112 may also be in the shape of a connector, as shown in Fig. 8.

[0025] 1 and 3-5, the case 120 has a housing area CA, which is open in the first direction (X direction). The thermistor assembly 110 is housed in the housing area CA of the case 120.

[0026] The second resin portion 130 is made of resin and is disposed within the housing area CA of the case 120 so as to seal the first resin portion 113, as shown in FIGS. 3 and 4. When the lead wire 140 is connected to the second end 1122 of the lead member 112, for example, the second resin portion 130 is disposed within the housing area CA of the case 120 so as to seal the entire thermistor assembly 110, as shown in FIG. 3. When the second end 1122 of the lead member 112 has a connector shape, the second resin portion 130 is disposed within the housing area CA of the case 120 so that the connector-shaped portion is outside the second resin portion 130, as shown in FIG. 9. FIG. 9 is a diagram illustrating the relationship between the lead member 112 and the second resin portion 130.

[0027] For example, before the second resin part 130 is hardened, it is injected into the housing area CA of the case 120. Then, the thermistor assembly 110 is inserted into the second resin part 130 injected into the housing area CA of the case 120 so that the first resin part 113 is sealed by the second resin part 130. Then, the second resin part 130 is hardened in a state in which the first resin part 113 is sealed.

[0028] As described above, in this embodiment, the thermistor assembly 110 has rigidity as a whole. Therefore, in this embodiment, when the thermistor assembly 110 is inserted into the second resin part 130, the thermistor assembly 110 does not bend, and the thermistor 11 can be accurately positioned with respect to the case 120. As a result, it is possible to provide a temperature sensor in which the thermistor is accurately positioned with respect to the case.

[0029] In this case, it is preferable that the lead member 112 and the case 120 each have first guide portions 1123, 121 for positioning the thermistor 111 relative to the case 120 in the first direction (Z direction), as shown in Fig. 3. In the example shown in Fig. 3, the first guide portion 1123 of the lead member 112 is a surface facing in the direction opposite to the first direction (-Z direction), and the first guide portion 121 of the case 120 is a surface facing the first direction (Z direction). By fixing the thermistor assembly 110 to the case 120 so that these two surfaces are in contact, it becomes possible to accurately position the thermistor 111 relative to the case 120 in the first direction (Z direction).

[0030] 5, each of the lead member 112 and the case 120 may further include second guide portions 1124, 122 for positioning the thermistor 111 relative to the case 120 on a plane perpendicular to the first direction. In the example shown in FIG. 5, the second guide portion 122 of the case 120 is a groove extending from the accommodation area CA in the second direction (X direction) and in the direction opposite to the second direction (-X direction), and the second guide portion 1124 of the lead member 112 is a portion of the lead member 112 that fits into this groove. In the example shown in FIG. 5, the depth of this groove is set so that the bottom of the groove is in contact with the lead member 112, and the width of this groove in the third direction (Y direction) is set to be the same as the thickness of the lead member 112 in the third direction. Therefore, in the example shown in FIG. 5, the thermistor 111 can be accurately positioned relative to the case 120 on a plane perpendicular to the first direction (Z direction).

[0031] The temperature sensor 100 may further include a connecting member 150. The connecting member 150 is a member for connecting the temperature sensor 100 to an object to be measured. In this case, the case 120 has an insertion opening 123 for inserting the connecting member 150, and the connecting member 150 is inserted into the insertion opening 123.

[0032] The connection member 150 is, for example, a member with high thermal conductivity. When the connection member 150 is connected to the measurement object, the connection member 150 reaches the same temperature as the measurement object. Furthermore, the connection member 150 is a conductor. If the measurement object is a conductor through which a current flows, when the connection member 150 is connected to the measurement object, the current flowing through the measurement object flows through the connection member 150, and the connection member 150 reaches the same temperature as the measurement object.

[0033] Connection member 150 has, for example, hole 151. At this time, connection member 150 is inserted into insertion opening 123 of case 120 so that thermistor 111 is positioned inside hole 151. In this way, thermistor 111 is surrounded by connection member 150, and it becomes possible to accurately measure the temperature of connection member 150 (i.e., the temperature of the object to be measured) without being affected by the temperatures of other members. Hole 151 is, for example, a through-hole.

[0034] <Method of manufacturing the temperature sensor 100> Fig. 10 is a diagram showing an example of a method for manufacturing the temperature sensor 100. In the manufacturing method shown in Fig. 10, first, the thermistor assembly 110 is manufactured, and then the manufactured thermistor assembly 110 is used to manufacture the temperature sensor 100.

[0035] The thermistor 111 is connected to the first ends 1121 of the two lead members 112 (connecting step, step S1001). Then, the first resin portion 113 is molded by transfer molding so that the thermistor 111 is sealed in the first resin portion 113 (molding step, step 1002). The thermistor assembly 110 is manufactured through this connecting step (step S1001) and molding step (step S1002).

[0036] Thereafter, resin is injected into the housing area CA of the case 120 (injection step, step S1003). The injected resin is the resin of the second resin portion 130 before it hardens.

[0037] The thermistor assembly 110 is then inserted into the resin injected into the housing area CA of the case 120 so that the first resin portion 113 is sealed with the resin (insertion step, step S1004). At this time, the thermistor assembly 110 is inserted so that the first guide portion 1123 of the lead member 112 contacts the first guide portion 121 of the case 120. This allows the thermistor 111 to be accurately positioned in the first direction (Z direction) relative to the case 120. The thermistor assembly 110 is also inserted so that the second guide portion 1124 of the lead member 112 enters the groove (second guide portion 122) of the case 120. This allows the thermistor 111 to be accurately positioned in a plane perpendicular to the first direction (Z direction) relative to the case 120.

[0038] Finally, the resin injected into the housing area CA of the case 120 is hardened (hardening step, step S1005). As a result, the resin injected into the housing area CA of the case 120 is hardened, and the second resin part 130 is placed in the housing area CA of the case 120 so as to seal the first resin part 113, and the temperature sensor 100 is completed.

[0039] The present invention has been described above in terms of preferred embodiments thereof. While 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]

[0040] 100 Temperature Sensor 110 thermistor assembly 111 Thermistor of the thermistor assembly 100 112 Lead member of thermistor assembly 100 1121 First end of lead member 112 1122 second end of lead member 112 1123 First guide portion of lead member 112 1124 Second guide portion of lead member 112 113 First resin portion of the thermistor assembly 100 120 cases 121 first guide portion of case 120 122 second guide portion of case 120 123 Insertion port for case 120 130 Second resin part 140 lead wire 150 connecting member 151 Hole of connecting member 150

Claims

1. A thermistor assembly; a case having a storage area that is open in a first direction; a second resin portion; a connecting member for connecting to the object to be measured, The thermistor assembly includes a thermistor, two rigid lead members, and a first resin portion. First ends of the two lead members are connected to the thermistor; the thermistor is sealed by the first resin portion, the second resin portion is disposed in the accommodation region so as to seal the first resin portion; The connecting member has a hole, the case has an insertion opening into which the connection member is inserted, The connecting member is inserted into the insertion opening of the case so that the thermistor is located in the hole.

2. A thermistor assembly; a case having a storage area that is open in a first direction; a second resin portion; The thermistor assembly includes a thermistor, two rigid lead members, and a first resin portion. First ends of the two lead members are connected to the thermistor; the thermistor is sealed by the first resin portion, the second resin portion is disposed in the accommodation region so as to seal the first resin portion; The temperature sensor, wherein the lead member and the case have a first guide portion for positioning the thermistor relative to the case in the first direction.

3. A manufacturing method for manufacturing a temperature sensor, comprising: a manufacturing process of a thermistor assembly, comprising: a connecting process for connecting a thermistor to first ends of two rigid lead members; and a molding process for molding a first resin portion by transfer molding so that the thermistor is sealed in the first resin portion; an injection step of injecting resin into the housing area of ​​the case; an inserting step of inserting the thermistor assembly into resin injected into the housing area of ​​the case so that the first resin portion is sealed by the resin; and a curing step of curing the resin.

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