Temperature sensor

Abstract

Provided is a temperature sensor having excellent responsiveness. A temperature sensor (1) is provided with: a temperature measurement element (11); a housing body (13) in which the temperature measuring element (11) is embedded and housed; and a housing (20) having an accommodation space (46a) in which the accommodation body (13) is accommodated. The housing (20) includes: a first housing (40) having a recessed portion (46) defining an accommodation space (46a) therein, and having a temperature measurement surface in contact with a measurement object on the outside thereof; a second housing (30) that closes the opening of the recessed section (46); and a filling material (50) which fills the accommodating space (46a) and fills a gap between the accommodating body (13) and the first housing (40). The thermal conductivity of the material constituting the second case (30) is lower than the thermal conductivity of the material constituting the filler (50).

Description

Technical Field

[0001] This invention relates to a temperature sensor that houses a temperature sensing element internally. Background Technology

[0002] Previously, temperature sensors have been proposed for measuring the temperature of various objects (e.g., gases, liquids, etc.). For example, one type of conventional temperature sensor incorporates a thermistor for temperature measurement and is installed in a vehicle pipeline to measure the temperature of the fluid flowing within the pipeline (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2-245626 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In conventional temperature sensors, a protective tube with a closed opening is filled with protective resin, and a thermistor, leads extending from the thermistor, and all contacts between the leads and external wires are embedded in this protective resin. In actual use, heat transferred from the fluid being measured to the protective tube is transferred to the thermistor via the protective resin. More specifically, the heat received by the protective resin diffuses within it, raising its own temperature, and then transfers heat from the heated resin to the thermistor. Considering this principle of heat conduction, it is argued that in conventional temperature sensors, heat transferred from the protective tube to the protective resin diffuses throughout the entire protective resin, which occupies a large portion of the sensor's structure. As a result, it is difficult to improve the temperature sensor's responsiveness.

[0008] One of the objectives of this invention is to provide a temperature sensor with excellent responsiveness.

[0009] Technical solutions for solving technical problems

[0010] To achieve the above objectives, the temperature sensor of the present invention has the following features.

[0011] A temperature sensor comprises: a temperature sensing element; a housing embedded therein and housing the temperature sensing element; and a housing having a receiving space for housing the housing, characterized in that...

[0012] The housing comprises: a first housing having an internal recess that defines the receiving space and an external temperature measuring surface that contacts the object being measured; a second housing assembled to the first housing and blocking the opening of the recess; and a filling material that fills the receiving space and buries the gap between the receiving body and the first housing.

[0013] The thermal conductivity of the material constituting the second shell is lower than that of the material constituting the filler material.

[0014] The effects of the invention

[0015] According to the temperature sensor of the present invention, a concave portion of the first housing defines a receiving space, in which a receiving body is accommodated, and the receiving body accommodates a temperature sensing element. A second housing blocks the opening of the receiving space, and a filling material is filled into the gap within the receiving space. Here, the thermal conductivity of the material constituting the second housing is lower than that of the material constituting the filling material. It should be noted that representative quantities related to the thermal conductivity of a material include thermal conductivity, thermal diffusivity, and specific heat capacity. The level of "thermal conductivity" in this invention can also be referred to as the level of thermal conductivity. In the temperature sensor of this embodiment, because the thermal conductivity of the second housing is relatively low, heat is less likely to transfer at the interface between the second housing and the filling material compared to a case where there is no difference in thermal conductivity between the second housing and the filling material. In other words, heat is less likely to dissipate from the filling material to the second housing. Therefore, the temperature of the filling material itself rises rapidly due to the heat transferred from the first housing to the filling material, and the temperature sensing element can quickly detect its temperature change. Therefore, the temperature sensor of the present invention has superior responsiveness compared to conventional temperature sensors.

[0016] The present invention has been briefly described above. Furthermore, the details of the present invention can be further clarified by referring to the accompanying drawings and understanding the specific embodiments described below. Attached Figure Description

[0017] Figure 1 This is a perspective view of a temperature sensor according to an embodiment of the present invention.

[0018] Figure 2 It is used for the purpose of... Figure 1 The temperature sensor shown is installed in the mounting hole of the object being installed, which is equivalent to... Figure 1 A sectional view of section AA.

[0019] Figure 3 yes Figure 2 An enlarged view of part B.

[0020] Figure 4 It is used for explanation Figure 1 A side view showing the assembly steps of the temperature sensor.

[0021] Figure 5 yes Figure 4 CC section view.

[0022] Figure 6 It means in Figure 1 The side view (partial sectional view) shows the temperature sensor being assembled with the resin housing inserted at an angle relative to the concave portion of the metal frame.

[0023] Explanation of reference numerals in the attached figures

[0024] 1: Temperature sensor;

[0025] 11: Thermistor element (temperature sensing element);

[0026] 12: terminal;

[0027] 13: Container;

[0028] 20: Shell;

[0029] 30: Resin housing (second housing);

[0030] 31: Insertion section;

[0031] 34: Groove section;

[0032] 40: Metal frame (first housing);

[0033] 41: Small diameter part (wall part);

[0034] 45: Bottom wall (wall);

[0035] 46: Concave portion;

[0036] 46a: Accommodation space;

[0037] 50: Filler material. Detailed Implementation

[0038] <Implementation Method>

[0039] Hereinafter, the temperature sensor 1 according to an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 2 As shown, Figure 1 The temperature sensor 1 shown is used when inserted into and fixed to the mounting hole 3 of the mounting object 2. The mounting object 2 is, for example, the wall of a device containing a flow path for vehicle coolant; in this case, the temperature sensor 1 mounted on the mounting object functions to measure the temperature of the coolant within the device. The temperature sensor 1 consists of a thermistor 10 and a housing 20 that internally houses the thermistor 10.

[0040] For ease of explanation, the following is as follows: Figure 1 As shown, "front," "rear," "left," "right," "up," and "down" are defined. The "front-rear direction," "left-right direction," and "up-down direction" are orthogonal to each other. The front-rear, left-right, and up-down directions may not necessarily be consistent with the front-rear, left-right, and up-down directions of the vehicle on which the temperature sensor 1 is mounted. The components constituting the temperature sensor 1 will be described in turn below.

[0041] First, let's explain the thermistor 10. For example... Figure 2 and Figure 3 As shown, the thermistor 10 comprises a thermistor element 11, a pair of rod-shaped metal terminals 12 extending upward from the thermistor element 11, and a resin housing 13 that houses the thermistor element 11 entirely within it. The housing 13 is, for example, a molded body (one-piece molded body) made of epoxy resin. The thermistor element 11 is integrated with the housing 13, for example, by transfer molding (one-piece molding). The pair of terminals 12 protrude linearly upward from the upper surface of the housing 13, spaced apart laterally, and exposed on the outside of the housing 13. Most of the exposed portion of the pair of terminals 12 is housed (embedded) within the resin housing 30 and filler material 50, which constitute the housing 20 (see reference 20). Figure 2 (etc.). In this example, a pair of terminals 12 has a straight shape, but a pair of terminals 12 may also have a curved shape depending on the shape of the resin housing 30, etc.

[0042] The resin-made housing 13 is a molded part with a generally rectangular parallelepiped shape. In other words, the housing 13 is molded into a pre-designed shape using a mold. This suppresses deviations in the shape of the housing 13. The housing 13 has a generally rectangular parallelepiped shape with an outer surface consisting of six faces. Normally, in a housing with such a shape, if a working fixture or the like comes into contact with the interface between adjacent faces, there is a concern that stress concentration may occur in that area, leading to deformation of the housing. However, in the temperature sensor 1, the housing 13 is housed inside the housing 20, so even though the housing 13 has such a molded shape, deformation of the housing 13 can be appropriately suppressed.

[0043] Next, the housing 20 will be described. For example... Figure 1 and Figure 2 As shown, the housing 20 is composed of a resin housing 30, a metal frame 40, and a filling material 50.

[0044] First, the resin housing 30 will be described. The resin housing 30 is, for example, a molded body (secondary molded body) made of PPS (polyphenylene sulfide) resin. The thermal conductivity of the resin material constituting the resin housing 30 is lower than that of the resin material constituting the housing 13. For example... Figure 2 As shown, the resin housing 30 integrally comprises a generally elongated cylindrical insertion portion 31 extending in the vertical direction and a generally rectangular box-shaped connector portion 32 with a cover-like shape located above the insertion portion 31 and extending upward. The resin housing 30 as a whole has a shape extending in the vertical direction. The insertion portion 31 is the portion that inserts into the recessed portion 46 of the metal frame 40 (described later). Figure 2 and Figure 4 (etc.). The upper end opening of the connector section 32.

[0045] like Figure 2 As shown, in the resin housing 30 (insertion portion 31 + connector portion 32), the portions of a pair of terminals 12 extending upward from the receiver 13 (one-piece molded body), except for the front end portion 12a and the base end portion 12b, are integrally held. The front end portion 12a of the pair of terminals 12 protrudes upward from the inner wall (lower end wall) of the connector portion 32 through the hollow portion of the connector portion 32, and is exposed outside the resin housing 30 through the upper opening of the connector portion 32 (see reference). Figure 2 (etc.). The base end portion 12b of a pair of terminals 12 protrudes downward from the lower end of the insertion portion 31 and is exposed outside the resin housing 30 between the housing 13 (primary molded body) and the resin housing 30 (secondary molded body).

[0046] It should be noted that in this example, the pair of terminals 12 extending upward from the housing 13 have a simple straight line shape. Therefore, by inserting the pair of terminals 12 into a pair of through holes provided in the molded resin housing 30, the portion of the pair of terminals 12, except for the front end 12a and the base end 12b, can be held entirely in the resin housing 30. As another manufacturing method, insertion molding (secondary molding) can also be performed by embedding the pair of terminals 12 in the resin housing 30. The former manufacturing method has the advantage of omitting the insertion molding (secondary molding) process. When the pair of terminals 12 are bent, it is difficult to apply the former manufacturing method, so the latter insertion molding is performed.

[0047] A circular protrusion 33 protruding laterally over the entire circumferential area is provided on the outer surface of the junction of the insertion part 31 and the connector part 32 (see reference). Figure 2 The annular pressing piece 47, which is later described, is pressed and fixed to the annular protrusion 33. At multiple circumferential locations (four locations in this example) on the outer peripheral surface of the generally elongated cylindrical insertion portion 31, grooves 34 extending vertically from the lower end to the upper part of the outer surface are formed (see reference). Figure 4 and Figure 5The function and effect of forming such a groove 34 will be explained later. As described above, the resin housing 30 holds the pair of terminals 12 (i.e., thermistors 10) with the front end 12a and base end 12b of the pair of terminals 12 exposed outside the resin housing 30.

[0048] Next, the metal frame 40 will be described. For example... Figure 1 and Figure 2 As shown, the metal frame 40 has a cylindrical shape extending vertically, and integrally comprises: a cylindrical small-diameter portion 41; a cylindrical middle-diameter portion 42 located above the small-diameter portion 41 and having an outer diameter larger than the small-diameter portion 41; a cylindrical large-diameter portion 43 located above the middle-diameter portion 42 and having an outer diameter larger than the middle-diameter portion 42; and a flange portion 44 located above the large-diameter portion 43 and having a hexagonal shape with an outer circumference larger than the large-diameter portion 43. The outer diameter of the large-diameter portion 43 is designed to be a value corresponding to the inner diameter of the mounting hole 3 of the mounting object 2 (a value slightly smaller than that inner diameter) (see reference). Figure 2 ).

[0049] Inside the metal frame 40, a long, cylindrical recess 46 extending vertically is formed throughout the entire vertical region of the metal frame 40. The lower end of the recess 46 (i.e., the lower end of the small-diameter portion 41) is blocked by the bottom wall 45, and the upper end of the recess 46 (i.e., the upper end of the flange portion 44) is open. The inner diameter of the recess 46 is designed to correspond to (a value slightly larger than) the outer diameter of the insertion portion 31 of the resin housing 30 (see reference). Figure 2 wait).

[0050] On the upper end face of the flange portion 44, a circular pressing piece 47 protruding upward over the entire circumferential area is provided in a manner that surrounds the upper opening of the concave portion 46 (see reference). Figure 1 and Figure 2 The portion of the concave portion 46 extending vertically that belongs to the small-diameter portion 41 (the portion near the lower end of the concave portion 46 including the lower end) defines a receiving space 46a (see also...). Figure 3 The thermistor 10 is housed in the accommodating space 46a, and is filled with a filler material 50 (see reference). Figure 2 (etc.). Here, the small diameter portion 41 and the bottom wall 45 correspond to the "wall portion of the present invention with one side (outer surface) being a temperature measuring surface and the other side (inner surface) facing the receiving space 46a".

[0051] like Figure 4As shown, the insertion portion 31 of the resin housing 30 is inserted into the recessed portion 46 of the metal frame 40 while the filler material 50 is injected. More specifically, firstly, the liquid filler material 50 is injected into the recessed portion 46 through the upper opening until it fills at least the entire receiving space 46a located near the lower end of the recessed portion 46. The filler material 50 is, for example, made of epoxy resin.

[0052] Regarding the thermal conductivity of the above materials, the thermal conductivity of PPS (the material constituting the resin shell 30) used in this example is lower than that of epoxy resin (the material constituting the filler material 50) used in this example.

[0053] Next, the insertion portion 31 of the resin housing 30 (and the receiving body 13 connected to the insertion portion 31 via the base ends 12b of a pair of terminals 12) is inserted into the recessed portion 46 through the upper opening of the recessed portion 46. During the insertion process of the insertion portion 31 into the recessed portion 46, the receiving body 13 and the base ends 12b of the pair of terminals 12 can be embedded in the filling material 50 while the filling material 50 is retracted into the groove 34 formed on the outer surface of the insertion portion 31 (see reference). Figure 4 and Figure 5 As a result, bubbles and other particles that could affect the responsiveness of the temperature sensor 1 are contained in the filler material 50.

[0054] Furthermore, during the insertion process where the insertion part 31 is inserted into the concave part 46, such as Figure 6 As indicated by the white arrow, even when a torque in the tilting direction acts on the insertion portion 31, causing the insertion portion 31 to tilt relative to the concave portion 46, the insertion portion 31 contacts the inner circumferential surface of the concave portion 46 before the receiving body 13 contacts the inner circumferential surface of the concave portion 46, due to the longer vertical length of the insertion portion 31 and the smaller gap between the outer circumferential surface of the insertion portion 31 and the inner circumferential surface of the concave portion 46. As a result, deformation of the receiving body 13 caused by contact between the receiving body 13 and the inner circumferential surface of the concave portion 46 can be suppressed.

[0055] When the insertion of the insertion part 31 into the concave part 46 is completed, such as Figure 2 and Figure 3As shown, the upper opening of the concave portion 46 is blocked by the insertion portion 31, and the base ends 12b of the accommodating body 13 and the pair of terminals 12 are entirely embedded in the filling material 50. Furthermore, the gaps between the outer surfaces of the accommodating body 13 and the base ends 12b of the pair of terminals 12 and the lower end face of the insertion portion 31 of the resin housing 30, and between the outer surfaces of the accommodating body 13 and the base ends 12b of the pair of terminals 12 and the inner wall surfaces of the concave portion 46 and the bottom wall 45 of the metal frame 40, are filled by the filling material 50. The accommodating space 46a, which contains the accommodating body 13 and is filled with the filling material 50, is sealed by the resin housing 30 (the insertion portion 31), which has a lower thermal conductivity than the filling material 50. It should be noted that after the insertion portion 31 is inserted, the liquid level of the filling material 50 increases by the volume of the accommodating body 13 and the base ends 12b of the pair of terminals 12 embedded in the filling material 50 compared to before the insertion portion 31. That is, when the insertion part 31 is fully inserted, the filling material 50 not only fills the entire space (=the entire receiving space 46a) divided by the portion of the concave part 46 belonging to the small diameter part 41, but also fills part or all of the space divided by the portion of the concave part 46 belonging to the middle diameter part 42 (see reference). Figure 2 and Figure 3 ).

[0056] When the insertion part 31 is inserted into the concave part 46, the annular pressing piece 47 of the metal frame 40 is pressed and fixed to the annular protrusion 33 of the resin housing 30, thereby fixing the resin housing 30 relative to the metal frame 40, and the filling material 50 filling the concave part 46 is cured by natural cooling. Thus, the housing 20 composed of the resin housing 30, the metal frame 40, and the filling material 50 is completed (see reference). Figure 1 and Figure 2 ), and complete Figure 1 Temperature sensor 1 is shown.

[0057] like Figure 2 As shown, the completed temperature sensor 1 is used with the portion of the metal frame 40 below the flange 44 inserted from the top into the mounting hole 3 of the mounting object 2, and the opposite connector (not shown) connected to the temperature detection device (not shown) engaged with the connector portion 32. With the temperature sensor 1 (metal frame 40) fully inserted into the mounting hole 3, the flange 44 is engaged with the edge of the mounting hole 3, the large diameter portion 43 is engaged with the mounting hole 3, the medium diameter portion 42 is located within the mounting hole 3, and the small diameter portion 41 protrudes from the mounting hole 3 and is located within the aforementioned flow path. It should be noted that, at this time, it is preferable to arrange the temperature sensor 1 such that the surface of the cooling water in the flow path is between the lower end of the insertion portion 31 and the upper end of the container 13. That is, the small diameter portion 41 in the metal frame 40 and the outer surface of the bottom wall 45 constitute a "temperature measuring surface" that contacts the cooling water (the object being measured) flowing in the aforementioned flow path.

[0058] The heat from the cooling water (the object being measured) flowing in the aforementioned flow path is transferred to the filling material 50 via the small-diameter portion 41, which has an outer surface constituting the "temperature measuring surface," and the bottom wall 45. The heat transferred to the filling material 50 diffuses within it, causing the temperature of the filling material 50 (i.e., the container 13 embedded within it) to rise. The thermistor element 11 embedded in the container 13 outputs an electrical signal representing the temperature around the thermistor element 11 (the temperature of the container 13). This signal is input to a temperature detection device to detect the temperature around the thermistor element 11 (i.e., the temperature of the object being measured). Furthermore, the heat transferred to the filling material 50 is not only transferred from the filling material 50 to the thermistor element 11 but also from the filling material 50 to the thermistor element 11 via the terminal 12. This allows for more rapid detection of the temperature around the thermistor element 11.

[0059] In temperature sensor 1, the small-diameter portion 41, which forms the outer surface of the "temperature measuring surface," and the inner surface of the bottom wall 45 face the receiving space 46a filled with filler material 50. Therefore, the heat from the cooling water (the object being measured) flowing in the aforementioned flow path is rapidly transferred to the filler material 50 filled in the receiving space 46a via the small-diameter portion 41 and the bottom wall 45. Furthermore, as described above, the receiving space 46a, which houses the container 13 and is filled with filler material 50, is sealed by the insertion portion 31 of the resin housing 30, which has a lower thermal conductivity than the filler material 50. Therefore, the heat transferred to the filler material 50 can rapidly raise the temperature of the filler material 50 (i.e., the container 13). Moreover, the outer surface of the base end portion 12b of the pair of terminals 12 connected to the thermistor element 11 is in direct contact with the filler material 50. Therefore, the heat transferred to the filler material 50 is easily transferred to the thermistor element 11 via the metal (i.e., highly thermally conductive) terminals 12. As a result, even when the temperature of the cooling water (the object being measured) flowing in the aforementioned flow path changes drastically, the thermistor element 11 within the container 13 can quickly detect this temperature change. In other words, the temperature sensor 1 exhibits excellent responsiveness.

[0060] <Function & Effect>

[0061] As described above, in the temperature sensor 1 of this embodiment, the second housing (resin housing 30) blocks the opening of the concave portion 46 of the first housing (metal frame 40) that divides the receiving space 46a. A receiving body 13 is housed in the receiving space 46a, and this receiving body 13 houses a temperature sensing element (thermostat element 11). Filler material 50 fills the gaps in the receiving space 46a. Furthermore, the thermal conductivity of the material constituting the second housing 30 is lower than that of the material constituting the filler material 50. Therefore, the receiving space 46a is sealed by the second housing 30, which has lower thermal conductivity, so the heat transferred from the first housing 40 to the filler material 50 causes the temperature of the filler material 50 to rise rapidly, and the temperature sensing element 11 inside the receiving body 13 can quickly detect its temperature. Therefore, the temperature sensor 1 of this embodiment has excellent responsiveness.

[0062] Furthermore, the heat transferred from the first housing (metal frame 40) to the filling material 50 is transferred not only to the temperature sensing element (thermostat element 11) via the filling material 50, but also from the filling material 50 to the temperature sensing element 11 via the terminal 12. The terminal 12 is metal, which typically has higher thermal conductivity than the filling material 50. As a result, the responsiveness of the temperature sensor 1 can be further improved.

[0063] Furthermore, according to the temperature sensor 1 of this embodiment, the insertion portion 31 of the second housing 30 has a groove 34 extending along the insertion direction toward the recessed portion 46 on its outer surface. Therefore, when manufacturing the temperature sensor 1, if the filling material 50 is pre-filled into the recessed portion 46 of the first housing 40, and the accommodating body 13 and the insertion portion 31 of the second housing 30 are inserted into the recessed portion 46, the accommodating body 13 can be embedded in the filling material 50 while the filling material 50 is retracted into the groove 34 of the insertion portion 31. As a result, air bubbles and other particles that affect the responsiveness of the temperature sensor 1 can be suppressed from remaining in the filling material 50. Therefore, the responsiveness of the temperature sensor 1 can be improved.

[0064] Furthermore, in the temperature sensor 1 according to this embodiment, one side of the wall portion (small diameter portion 41 and bottom wall 45) of the first housing 40 is a temperature-sensing surface, and the other side of the wall portion 41, 45 faces the receiving space 46a. Therefore, in actual use of the temperature sensor 1, heat can be rapidly transferred from the object being measured through the temperature-sensing surface to the filling material within the receiving space 46a. Thus, the responsiveness of the temperature sensor 1 can be improved.

[0065] Furthermore, in the temperature sensor 1 according to this embodiment, the housing 13 into which the temperature sensing element 11 is embedded is a molded part with a predetermined molding shape. In other words, the housing 13 is not molded by the conventional flow impregnation method, but is molded using a mold designed to have a predetermined molding shape. As a result, the shape deviation of the housing 13 is reduced compared to the conventional method. Therefore, for example, the housing 13 can be formed with high precision in a shape suitable for temperature measurement, corresponding to the gas, liquid, etc., that is being measured. Therefore, the responsiveness of the temperature sensor 1 can be improved.

[0066] Furthermore, according to the temperature sensor 1 of this embodiment, the housing 13 has a molded shape whose outer surface is composed of multiple surfaces (six surfaces). In this case, for example, if a work clamp or the like comes into contact with the interface between adjacent surfaces, stress concentration occurs in that part, which may cause deformation of the housing 13. However, since the housing 13 is housed inside the housing 20, deformation of the housing 13 can be appropriately suppressed even though the housing 13 has such a molded shape. Therefore, the temperature sensor 1 can perform the designed temperature measurement performance.

[0067] <Other Options>

[0068] It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the above-described embodiments, and appropriate modifications and improvements can be made. Furthermore, the material, shape, size, quantity, and arrangement of the constituent elements in the above embodiments can be arbitrary and not limited, as long as they can realize the present invention.

[0069] Here, the features of the embodiments of the temperature sensor 1 of the present invention described above are briefly summarized as shown in [1] to [6] below.

[0070] [1] A temperature sensor (1) comprising: a temperature sensing element (11); a housing (13) embedded therein and housing the temperature sensing element (11); and a housing (20) having a housing space (46a) for housing the housing (13), characterized in that,

[0071] The housing (20) comprises: a first housing (40) having an internal recess (46) that divides the receiving space (46a) and an external temperature measuring surface that contacts the object being measured; a second housing (30) assembled to the first housing (40) and blocking the opening of the recess (46); and a filling material (50) that fills the receiving space (46a) and buries the gap between the receiving body (13) and the first housing (40);

[0072] The thermal conductivity of the material constituting the second housing (30) is lower than that of the material constituting the filler material (50).

[0073] According to the temperature sensor structure described above [1], the concave portion of the first housing divides into a receiving space, which houses a receiving body that houses a temperature sensing element. The second housing blocks the opening of the receiving space, and the gaps within the receiving space are filled with a filling material. Here, the thermal conductivity of the material constituting the second housing is lower than that of the material constituting the filling material. It should be noted that representative quantities related to the thermal conductivity of a material include thermal conductivity, thermal diffusivity, and specific heat capacity. The level of "thermal conductivity" in this invention can also be referred to as the level of thermal conductivity. In the temperature sensor of this solution, since the thermal conductivity of the second housing is relatively low, heat is difficult to transfer at the interface between the second housing and the filling material compared to the case where there is no difference in thermal conductivity between the second housing and the filling material. In other words, heat is difficult to dissipate from the filling material to the second housing. Therefore, the temperature of the filling material itself rises rapidly due to the heat transferred from the first housing to the filling material, and the temperature sensing element can quickly detect its temperature change. Therefore, the temperature sensor of this solution has excellent responsiveness compared to conventional temperature sensors.

[0074] [2] In the temperature sensor described in [1] above,

[0075] It also has a terminal (12) that is connected to the temperature sensing element (11) and extends from the housing (13).

[0076] The terminal (12) is in contact with the filling material (50).

[0077] According to the temperature sensor with the structure described above [2], the heat transferred from the first housing to the filling material is transferred not only to the temperature sensing element via the filling material, but also from the filling material to the temperature sensing element via the terminals. The terminals are made of metal, which typically has higher thermal conductivity than the filling material. Therefore, the responsiveness of the temperature sensor can be further improved.

[0078] [3] In the temperature sensor (1) described in [2] above,

[0079] The second housing (30) has an insertion portion (31) that holds the terminal (12) and is inserted into the recess (46) to block the opening.

[0080] The insertion part (31) has a groove (34) on its outer surface that extends along the insertion direction into the concave part (46).

[0081] According to the temperature sensor with the structure described above [3], the insertion portion of the second housing has a groove on its outer surface extending along the insertion direction into the concave portion. Therefore, when manufacturing the temperature sensor, if a filling material is pre-filled into the concave portion of the first housing, and the accommodator and the insertion portion of the second housing are inserted into the concave portion, the accommodator can be embedded in the filling material while the filling material is retracted into the groove of the insertion portion. As a result, air bubbles and other particles that affect the responsiveness of the temperature sensor can be suppressed from remaining in the filling material. Therefore, the responsiveness of the temperature sensor can be improved.

[0082] [4] In the temperature sensor (1) described in [1] above,

[0083] The first housing (40) has walls (41, 45), one side of which is the temperature measuring surface, and the other side of which faces the receiving space (46a).

[0084] According to the temperature sensor structure described above [4], one side of the wall of the first housing is the temperature sensing surface, and the other side of the wall faces the receiving space. Therefore, in actual use of the temperature sensor, heat can be rapidly transferred from the object being measured through the temperature sensing surface to the filling material within the receiving space. Thus, the responsiveness of the temperature sensor can be improved.

[0085] [5] In the temperature sensor (1) described in [1] above,

[0086] The container (13) is a molded part with a specified molding shape.

[0087] According to the temperature sensor with the structure described above [5], the housing into which the temperature sensing element is embedded is a molded part with a predetermined molding shape. In other words, the housing is not formed by the conventional flow impregnation method, but by using a mold designed with a predetermined molding shape. As a result, the deviation of the housing shape is reduced compared to the past. Therefore, for example, it is possible to form the housing with high precision in a shape suitable for temperature measurement, corresponding to the gas, liquid, etc., that is being measured. Therefore, the responsiveness of the temperature sensor can be improved.

[0088] [6] In the temperature sensor (1) described in [5] above,

[0089] The shaped form of the container (13) is a shape whose outer surface is composed of multiple surfaces.

[0090] According to the temperature sensor with the structure described above [6], the housing has a molded shape whose outer surface is composed of multiple surfaces. In this case, for example, if a work fixture or the like comes into contact with the interface between adjacent surfaces, stress concentration occurs in that part, which may cause deformation of the housing. However, since the housing is housed inside the shell, deformation of the housing can be appropriately suppressed even though the housing has such a molded shape. Therefore, the temperature sensor can perform its designed temperature measurement performance.

Claims

1. A temperature sensor comprising: a temperature sensing element; a housing embedded therein and housing the temperature sensing element; and a housing having a receiving space for housing the housing, characterized in that, The housing comprises: a first housing having an internal recess that defines the receiving space and an external temperature measuring surface that contacts the object being measured; a second housing assembled to the first housing and blocking the opening of the recess; and a filling material that fills the receiving space and buries the gap between the receiving body and the first housing. The thermal conductivity of the material constituting the second shell is lower than that of the material constituting the filler material.

2. The temperature sensor according to claim 1, It also includes terminals that are connected to the temperature sensing element and extend from the housing. The terminal is in contact with the filler material.

3. The temperature sensor according to claim 2, The second housing has an insertion portion that holds the terminal and inserts into the recess to block the opening. The insertion part has a groove on its outer surface that extends along the insertion direction into the concave part.

4. The temperature sensor according to claim 1, The first housing has a wall, one side of which is the temperature measuring surface, and the other side of which faces the receiving space.

5. The temperature sensor according to claim 1, The container is a molded part with a specified molding shape.

6. The temperature sensor according to claim 5, The shaped form of the container is a shape whose outer surface is composed of multiple surfaces.

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