Temperature sensor

Abstract

To provide a temperature sensor with excellent response performance. [Solution] The temperature sensor 1 comprises a temperature measuring element 11, a housing 13 in which the temperature measuring element 11 is embedded and housed, and a housing 20 having a storage space 46a for housing the housing 13. The housing 20 comprises a first housing 40 having a concave portion 46 inside that defines the storage space 46a and a temperature measuring surface on the outside that will come into contact with the object to be measured, a second housing 30 that closes the opening of the concave portion 46, and a filler material 50 that fills the storage space 46a and fills the gap between the housing 13 and the first housing 40. The thermal conductivity of the material constituting the second housing 30 is lower than that of the material constituting the filler material 50.

Description

Technical Field

[0001] The present invention relates to a temperature sensor having a temperature measuring element stored therein.

Background Art

[0002] Conventionally, temperature sensors for measuring the temperatures of various measurement targets (for example, gases, liquids, etc.) have been proposed. For example, one of the conventional temperature sensors incorporates a thermistor for temperature measurement and is attached to an in-vehicle pipe to measure the temperature of the fluid flowing through the in-vehicle pipe (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described conventional temperature sensor, a protective resin is filled in a protective tube with one opening closed, and a thermistor, a lead wire extending from the thermistor, and all of the contacts between the lead wire and an external electric wire are embedded in the protective resin. When this temperature sensor is actually used, the heat transmitted from the fluid of the measurement target to the protective tube is transmitted to the thermistor through the protective resin. More specifically, the heat received by the protective resin diffuses within the protective resin to increase the temperature of the protective resin itself, and the heat is transmitted from the heated protective resin to the thermistor. Considering such a heat transfer principle, in the conventional temperature sensor, it is considered that it is difficult to improve the response performance of the temperature sensor as a result of the heat transmitted from the protective tube to the protective resin diffusing throughout the protective resin that occupies most of the structure of the temperature sensor.

[0005] One object of the present invention is to provide a temperature sensor having excellent response performance. [Means for solving the problem]

[0006] To achieve the aforementioned objectives, the temperature sensor according to the present invention is characterized by the following:

[0007] A temperature sensor comprising a temperature measuring element, a housing in which the temperature measuring element is embedded and housed, and a housing having a storage space for housing the housing, The aforementioned housing is The device comprises a first housing having a concave portion inside that defines the storage space and a temperature-measuring surface on the outside that will come into contact with the object to be measured; a second housing assembled to the first housing and closing the opening of the concave portion; and a filler material that fills the storage space and fills the gap between the housing and the first housing. The thermal conductivity of the material constituting the second housing is lower than that of the material constituting the filler. It must be a temperature sensor. [Effects of the Invention]

[0008] In the temperature sensor of the present invention, a concave portion of the first housing defines a storage space, a housing containing a temperature measuring element is stored in this storage space, the opening of the storage space is closed by the second housing, and a filler material is filled into the gap within the storage space. Here, the thermal conductivity of the material constituting the second housing is lower than that of the material constituting the filler material. Typical quantities related to the heat transfer of materials include thermal conductivity, thermal diffusivity, and specific heat capacity. Of these, the high or low "thermal conductivity" in the present invention can also be rephrased as the high or low thermal conductivity. In this temperature sensor configuration, because the thermal conductivity of the second housing is relatively low, heat is less easily transferred at the boundary between the second housing and the filler material compared to a case where there is no difference in thermal conductivity between the second housing and the filler material. In other words, heat is less likely to escape from the filler material to the second housing. Therefore, the temperature of the filler material itself rises rapidly due to the heat transferred from the first housing to the filler material, and the temperature measuring element can quickly detect the temperature change. Therefore, the temperature sensor of the present invention has superior response performance compared to conventional temperature sensors.

[0009] The present invention has been briefly described above. Further details of the present invention will be clarified by referring to the accompanying drawings and reading through the embodiments for carrying out the invention described below. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a perspective view showing a temperature sensor according to an embodiment of the present invention. [Figure 2] Figure 2 is a cross-sectional view corresponding to section AA in Figure 1, illustrating the state in which the temperature sensor shown in Figure 1 is installed in the mounting hole of the target object. [Figure 3] Figure 3 is an enlarged view of section B in Figure 2. [Figure 4] Figure 4 is a side view illustrating the assembly procedure for the temperature sensor shown in Figure 1. [Figure 5] Figure 5 is a cross-sectional view of the CC shown in Figure 4. [Figure 6]Figure 6 is a side view (partially a cross-sectional view) showing the state in which the insertion part of the resin housing is inserted at an angle into the concave part of the metal housing during the assembly process of the temperature sensor shown in Figure 1. [Modes for carrying out the invention]

[0011] <Embodiment> Hereinafter, a temperature sensor 1 according to an embodiment of the present invention will be described with reference to the drawings. The temperature sensor 1 shown in Figure 1 is used in a state in which it is inserted into and fixed in a mounting hole 3 of the mounting target 2, as shown in Figure 2. The mounting target 2 is, for example, the wall of a device that has a built-in coolant flow path for a vehicle, and in this case, the temperature sensor 1 attached to the mounting target performs the function of measuring the temperature of the coolant inside the device. The temperature sensor 1 consists of a thermistor 10 and a housing 20 that houses the thermistor 10 inside.

[0012] For the sake of clarity, as shown in Figure 1, we define "front," "rear," "left," "right," "up," and "down." The "front-rear direction," "left-right direction," and "up-down direction" are orthogonal to each other. The front-rear direction, left-right direction, and up-down direction do not necessarily coincide with the front-rear direction, left-right direction, and up-down direction of the vehicle on which the temperature sensor 1 is mounted. The components that make up the temperature sensor 1 will be described in order below.

[0013] First, let's describe the thermistor 10. As shown in Figures 2 and 3, the thermistor 10 consists of 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 entire thermistor element 11 embedded inside. The housing 13 is, for example, a molded body (primary molded body) made of epoxy resin. The thermistor element 11 is integrated into the housing 13 by, for example, transfer molding (primary molding). The pair of terminals 12 protrude linearly upward from the upper surface of the housing 13, with a gap between them in the left-right direction, and are exposed to the outside of the housing 13. Most of the pair of terminals 12 exposed to the outside of the housing 13 will be housed (embedded) inside the resin housing 30 and filler material 50, which will be described later and constitute the housing 20 (see Figure 2, etc.). In this example, the pair of terminals 12 have a straight shape, but the pair of terminals 12 may have a curved shape depending on the shape of the resin housing 30, etc.

[0014] The resin housing 13 is a molded product having a roughly rectangular parallelepiped shape. In other words, the housing 13 is molded using a mold to have a pre-designed shape. This suppresses variations in the shape of the housing 13. The housing 13 has a roughly rectangular parallelepiped shape with an outer surface composed of six faces. Generally, with a housing of this shape, if a work jig or the like comes into contact with the boundary between adjacent faces, stress concentration occurs in that area, which can cause deformation of the housing. However, in the temperature sensor 1, since the housing 13 is housed inside the housing 20, deformation of the housing 13 can be properly suppressed even if the housing 13 has such a molded shape.

[0015] Next, the housing 20 will be described. As shown in Figures 1 and 2, the housing 20 is composed of a resin housing 30, a metal casing 40, and a filler material 50.

[0016] 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 heat conductivity of the resin material that composes the resin housing 30 is lower than that of the resin material that composes the housing 13. As shown in FIG. 2 and the like, the resin housing 30 integrally includes a substantially elongated columnar insertion portion 31 that extends in the vertical direction, and a connector portion 32 having a substantially rectangular box-shaped hood-like shape that is located above the insertion portion 31 and extends so as to protrude upward, and has a shape that extends in the vertical direction as a whole. The insertion portion 31 is a portion that will be inserted into a concave portion 46 (to be described later) of the metal housing 40 (see FIGS. 2 and 4 and the like). The upper end of the connector portion 32 is open.

[0017] As shown in FIG. 2, in the resin housing 30 (insertion portion 31 + connector portion 32), the entire portion of the pair of terminals 12 that extends upward from the housing 13 (primary molded body), excluding the tip portion 12a and the base end portion 12b, is integrally held. The tip portions 12a of the pair of terminals 12 protrude upward in the hollow portion of the connector portion 32 from the back wall (lower end wall) of the connector portion 32, and are exposed to the outside of the resin housing 30 through the upper end opening of the connector portion 32 (see FIG. 2 and the like). The base end portions 12b of the pair of terminals 12 protrude downward from the lower end of the insertion portion 31, and are exposed to the outside of the resin housing 30 between the housing 13 (primary molded body) and the resin housing 30 (secondary molded body).

[0018] In this example, since the pair of terminals 12 that extend upward from the housing 13 have a simple straight shape, by inserting the pair of terminals 12 into a pair of insertion holes provided in the resin housing 30 after molding, the entire portion of the pair of terminals 12 excluding the tip portion 12a and the base end portion 12b can be held by the resin housing 30. As another manufacturing method, insert molding (secondary molding) may be performed so that the pair of terminals 12 are embedded in the resin housing 30. The former manufacturing method has an advantage in that the process of insert molding (secondary molding) can be omitted. When the pair of terminals 12 are curved, it is difficult to apply the former manufacturing method, so the latter insert molding will be performed.

[0019] On the outer surface of the boundary portion between the insertion portion 31 and the connector portion 32, an annular protrusion 33 that protrudes laterally over the entire circumferential direction is provided (see FIG. 2). An annular caulking piece 47, which will be described later, of the metal housing 40 is caulked and fixed to the annular protrusion 33. Groove portions 34 extending in the vertical direction from the lower end to the upper end of the outer surface are formed at a plurality of locations (in this example, four locations) in the circumferential direction on the outer peripheral surface of the substantially slender columnar insertion portion 31 (see FIGS. 4 and 5). The actions and effects of forming such groove portions 34 will be described later. As described above, the resin housing 30 holds the pair of terminals 12 (that is, the thermistor 10) in a state where the tip portions 12a and base end portions 12b of the pair of terminals 12 and the housing 13 are exposed outside the resin housing 30.

[0020] Next, the metal housing 40 will be described. As shown in FIGS. 1 and 2 and the like, the metal housing 40 made of metal has a cylindrical shape that extends in the vertical direction as a whole, and includes 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 that of 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 that of 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 peripheral shape larger than that of the large-diameter portion 43, which are integrally provided. 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 target 2 (a value slightly smaller than the inner diameter) (see FIG. 2).

[0021] Inside the metal housing 40, an elongated columnar concave portion 46 that extends in the vertical direction over the entire vertical direction of the metal housing 40 is formed. The lower end of the concave portion 46 (that is, the lower end of the small-diameter portion 41) is blocked by a bottom wall 45, and the upper end of the concave portion 46 (that is, the upper end of the flange portion 44) is open. The inner diameter of the concave portion 46 is designed to be a value corresponding to the outer diameter of the insertion portion 31 of the resin housing 30 (a value slightly larger than the outer diameter) (see FIGS. 2 and the like).

[0022] The upper end surface of the flange portion 44 is provided with an annular crimping piece 47 that protrudes upward over the entire circumferential direction, surrounding the upper end opening of the concave portion 46 (see Figures 1 and 2). The portion of the concave portion 46 that extends in the vertical direction that belongs to the small diameter portion 41 (the portion near the lower end of the concave portion 46, including the lower end) defines the storage space 46a (see also Figure 3). The housing 13 of the thermistor 10 is stored in the storage space 46a, and the packing material 50 is filled in there (see Figure 2, etc.). Here, the small diameter portion 41 and the bottom wall 45 correspond to the "wall portion in the present invention where one surface (outer surface) is the temperature sensing surface and the other surface (inner surface) faces the storage space (46a)".

[0023] As shown in Figure 4, the insertion portion 31 of the resin housing 30 is inserted into the recessed portion 46 of the metal housing 40 with the filler material 50 injected into it. More specifically, first, the liquid filler material 50 is injected into the recessed portion 46 through the upper end opening of the recessed portion 46 until it fills at least the entire storage space 46a located near the lower end of the recessed portion 46. The filler material 50 is made of, for example, epoxy resin.

[0024] Regarding the thermal conductivity of the materials mentioned above, the thermal conductivity of the PPS (material constituting the resin housing 30) used in this example is lower than that of the epoxy resin (material constituting the filler 50) used in this example.

[0025] Next, the insertion portion 31 of the resin housing 30 (and the housing 13 connected to the insertion portion 31 via the base ends 12b of the pair of terminals 12) is inserted into the recessed portion 46 through the upper end opening of the recessed portion 46. During the insertion process of the insertion portion 31 into the recessed portion 46, the housing 13 and the base ends 12b of the pair of terminals 12 are embedded in the filler material 50, while the filler material 50 can escape into the groove 34 (see Figures 4 and 5) formed on the outer surface of the insertion portion 31. As a result, it is possible to suppress the retention of air bubbles and other particles in the filler material 50 that may affect the response performance of the temperature sensor 1.

[0026] Furthermore, during the insertion process of the insertion portion 31 into the concave portion 46, as shown by the white arrow in Figure 6, even if a moment in the tilting direction acts on the insertion portion 31 and the insertion portion 31 tilts relative to the concave portion 46, the insertion portion 31 contacts the inner surface of the concave portion 46 before the housing 13 contacts the inner surface of the concave portion 46 due to the length of the insertion portion 31 in the vertical direction and the small gap between the outer surface of the insertion portion 31 and the inner surface of the concave portion 46. As a result, deformation of the housing 13 caused by contact with the inner surface of the concave portion 46 can be suppressed.

[0027] When the insertion portion 31 is fully inserted into the recessed portion 46, as shown in Figures 2 and 3, the upper opening of the recessed portion 46 is closed by the insertion portion 31, the entire base end portion 12b of the housing 13 and the pair of terminals 12 are embedded in the filler material 50, and the gap between the outer surfaces of the housing 13 and the base end portion 12b of the pair of terminals 12 and the lower end surface of the insertion portion 31 of the resin housing 30, the inner wall surface of the recessed portion 46 of the metal housing 40, and the inner wall surface of the bottom wall 45 is filled with the filler material 50. The storage space 46a in which the housing 13 is stored and filled with the filler material 50 is sealed by the resin housing 30 (and its insertion portion 31), which has lower heat conductivity than the filler material 50. After the insertion of the insertion portion 31 is completed, the liquid level of the filler material 50 has risen by the volume of the housing 13 and the base end portion 12b of the pair of terminals 12 embedded in the filler material 50 compared to before the insertion of the insertion portion 31. In other words, when the insertion portion 31 is fully inserted, the filler material 50 fills not only the entire space defined by the small-diameter portion 41 of the concave portion 46 (= the entire storage space 46a), but also part or all of the space defined by the medium-diameter portion 42 of the concave portion 46 (see Figures 2 and 3).

[0028] Once the insertion of the insertion portion 31 into the concave portion 46 is complete, the annular crimping piece 47 of the metal housing 40 is crimped and fixed to the annular projection 33 of the resin housing 30, thereby fixing the resin housing 30 to the metal housing 40, and the filler material 50 filling the concave portion 46 solidifies by natural cooling. As a result, the housing 20 (see Figures 1 and 2), which is composed of the resin housing 30, the metal housing 40, and the filler material 50, is completed, and the temperature sensor 1 shown in Figure 1 is also completed.

[0029] As shown in Figure 2, the completed temperature sensor 1 is used with the portion of the metal housing 40 below the flange portion 44 inserted from above into the mounting hole 3 of the mounting target 2, and the mating connector (not shown) connected to the temperature detection device (not shown) fitted into the connector portion 32. When the temperature sensor 1 (metal housing 40) is inserted into the mounting hole 3, the flange portion 44 is locked to the edge of the mounting hole 3, the large diameter portion 43 is fitted into the mounting hole 3, the medium diameter portion 42 is located inside the mounting hole 3, and the small diameter portion 41 protrudes from the mounting hole 3 and is located in the flow path. At this time, it is preferable that the temperature sensor 1 is positioned so that the liquid level of the cooling water in the flow path is located between the lower end of the insertion portion 31 and the upper end of the housing 13. That is, the small diameter portion 41 and the outer surface of the bottom wall 45 of the metal housing 40 constitute the "temperature sensing surface" that contacts the cooling water (measurement target) flowing through the flow path.

[0030] The heat from the cooling water (the object being measured) flowing through the above-mentioned channel is transferred to the packing material 50 via the small-diameter portion 41 and the bottom wall 45, which have an outer surface constituting the "temperature sensing surface". The heat transferred to the packing material 50 spreads throughout the packing material 50, raising the temperature of the packing material 50 itself (i.e., the housing 13 embedded in the packing material 50). The thermistor element 11 embedded in the housing 13 outputs an electrical signal representing the temperature around the thermistor element 11 (the temperature of the housing 13), and this electrical signal is input to a temperature detection device, thereby detecting the temperature around the thermistor element 11 (i.e., the temperature of the object being measured). Furthermore, the heat transferred to the packing material 50 is not only transferred to the thermistor element 11 via the packing material 50, but also from the packing material 50 to the thermistor element 11 via the terminal 12. As a result, the temperature around the thermistor element 11 is detected even more quickly.

[0031] In the temperature sensor 1, the inner surfaces of the small-diameter portion 41 and the bottom wall 45, which constitute the "temperature sensing surface," face the storage space 46a filled with the packing material 50. Therefore, the heat of the cooling water (object to be measured) flowing through the above-mentioned channel is quickly transferred to the packing material 50 filled in the storage space 46a via the small-diameter portion 41 and the bottom wall 45. Furthermore, as described above, the storage space 46a, in which the housing 13 is housed and filled with the packing material 50, is sealed by the insertion portion 31 of the resin housing 30, which has lower heat conductivity than the packing material 50. Therefore, the heat transferred to the packing material 50 can quickly raise the temperature of the packing material 50 (i.e., the housing 13) itself. Moreover, the outer surface of the base end 12b of the pair of terminals 12 connected to the thermistor element 11 is in direct contact with the packing material 50. Therefore, the heat transferred to the packing material 50 is easily transferred to the thermistor element 11 via the metal (i.e., highly heat-conductive) terminals 12. As a result, even if the temperature of the cooling water (the object being measured) flowing through the above-mentioned channel changes rapidly, the thermistor element 11 inside the housing 13 can quickly detect the temperature change. In other words, the temperature sensor 1 has excellent response performance.

[0032] <Effects and Actions> As described above, according to the temperature sensor 1 of this embodiment, the second housing (resin housing 30) closes the opening of the concave portion 46 of the first housing (metal housing 40) that defines the storage space 46a, the housing 13 containing the temperature measuring element (thermistor element 11) is stored in the storage space 46a, and the filler material 50 is filled into the gap in the storage space 46a. Furthermore, the heat conductivity of the material constituting the second housing 30 is lower than that of the material constituting the filler material 50. As a result, the storage space 46a is sealed by the second housing 30, which has low heat conductivity, so that the heat transferred from the first housing 40 to the filler material 50 quickly raises the temperature of the filler material 50 itself, and the temperature measuring element 11 in the housing 13 can quickly detect that temperature. Therefore, the temperature sensor 1 of this embodiment has excellent response performance.

[0033] Furthermore, the heat transferred from the first housing (metal casing 40) to the filler material 50 is not only transmitted to the temperature measuring element (thermistor element 11) via the filler material 50, but also from the filler material 50 to the temperature measuring element 11 via the terminal 12. The terminal 12 is made of metal and typically has higher heat conductivity than the filler material 50. This further improves the response performance of the temperature sensor 1.

[0034] Furthermore, according to the temperature sensor 1 of this embodiment, the insertion portion 31 of the second housing 30 has a groove 34 on its outer surface that extends along the insertion direction into the concave portion 46. As a result, when manufacturing the temperature sensor 1, if a filler material 50 is injected into the concave portion 46 of the first housing 40 in advance, and the housing 13 and the insertion portion 31 of the second housing 30 are inserted into the concave portion 46, the housing 13 is embedded in the filler material 50 while the filler material 50 escapes into the groove 34 of the insertion portion 31. As a result, it is possible to suppress the retention of air bubbles and other particles in the filler material 50 that may affect the response performance of the temperature sensor 1. Therefore, the response performance of the temperature sensor 1 can be improved.

[0035] Furthermore, according to the temperature sensor 1 of this embodiment, one surface of the wall portion (small diameter portion 41 and bottom wall 45) of the first housing 40 is the temperature sensing surface, and the other surface of the wall portion 41, 45 faces the storage space 46a. As a result, when the temperature sensor 1 is actually used, heat can be quickly transferred from the object to be measured to the filling material in the storage space 46a via the temperature sensing surface. Therefore, the response performance of the temperature sensor 1 can be improved.

[0036] Furthermore, according to the temperature sensor 1 of this embodiment, the housing 13 in which the temperature measuring element 11 is embedded is a molded product having a predetermined molded shape. In other words, the housing 13 is not molded by the conventional fluid immersion method, but is molded using a mold designed to have a predetermined molded shape. As a result, variations in the shape of the housing 13 are reduced compared to the conventional method. Therefore, the housing 13 can be accurately formed to have a shape suitable for measuring the temperature of, for example, a gas or liquid to be measured. Thus, the response performance of the temperature sensor 1 can be improved.

[0037] Furthermore, according to the temperature sensor 1 of this embodiment, the housing 13 has a molded shape with an outer surface composed of multiple surfaces (six surfaces). In this case, for example, if a work jig or the like comes into contact with the boundary between adjacent surfaces, stress concentration may occur in this area, potentially causing deformation of the housing 13. However, since the housing 13 is housed inside the housing 20, deformation of the housing 13 can be properly suppressed even if the housing 13 has such a molded shape. Therefore, the temperature sensor 1 can perform temperature measurement as designed.

[0038] <Other embodiments> It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the embodiments described above, and can be modified, improved, etc. as appropriate. Furthermore, the material, shape, dimensions, number, placement, etc. of each component in the embodiments described above are arbitrary and not limited as long as they can achieve the present invention.

[0039] Here, the features of the embodiments of the temperature sensor 1 according to the present invention described above are briefly summarized and listed below in [1] to [6].

[0040] [1] A temperature sensor (1) comprising a temperature measuring element (11), a housing (13) in which the temperature measuring element (11) is embedded and housed, and a housing (20) having a storage space (46a) for housing the housing (13), The housing (20) is The device comprises a first housing (40) having a concave portion (46) inside that defines the storage space (46a) and a temperature sensing surface on the outside that will come into contact with the object to be measured; a second housing (30) assembled to the first housing (40) to close the opening of the concave portion (46); and a filler material (50) that fills the storage space (46a) to fill the gap between the housing (13) and the first housing (40), The thermal conductivity of the material constituting the second housing (30) is lower than that of the material constituting the filler (50). Temperature sensor (1).

[0041] In the temperature sensor configuration described in [1] above, the concave portion of the first housing defines a storage space, a housing containing a temperature measuring element is stored in this storage space, the opening of the storage space is closed by the second housing, and a filler material is filled into the gap within the storage space. Here, the thermal conductivity of the material constituting the second housing is lower than that of the material constituting the filler material. Typical quantities related to the heat transfer of materials include thermal conductivity, thermal diffusivity, and specific heat capacity. Of these, the high or low "thermal conductivity" in this invention can also be rephrased as the high or low thermal conductivity. In the temperature sensor configuration described above, because the thermal conductivity of the second housing is relatively low, heat is less likely to be transferred at the boundary between the second housing and the filler material compared to the case where there is no difference in thermal conductivity between the second housing and the filler material. In other words, heat is less likely to escape from the filler material to the second housing. Therefore, the temperature of the filler material itself rises rapidly due to the heat transferred from the first housing to the filler material, and the temperature measuring element can quickly detect the temperature change. Therefore, this temperature sensor configuration offers superior response performance compared to conventional temperature sensors.

[0042] [2] The temperature sensor described in [1] above, The temperature measuring element (11) is further provided with a terminal (12) that is connected to the housing (13), The terminal (12) contacts the filler material (50), Temperature sensor (1).

[0043] In the temperature sensor configuration described in [2] above, the heat transferred from the first housing to the filler is not only transferred to the temperature sensing element via the filler, but also from the filler to the temperature sensing element via the terminals. The terminals are made of metal and typically have higher thermal conductivity than the filler. This further improves the response performance of the temperature sensor.

[0044] [3] In the temperature sensor (1) described in [2] above, The aforementioned second housing (30) is The terminal (12) has an insertion portion (31) that holds the terminal (12) and is inserted into the recessed portion (46) to close the opening, The aforementioned insertion portion (31) is The outer surface of the insertion portion (31) has a groove (34) that extends in the direction of insertion into the concave portion (46), Temperature sensor (1).

[0045] According to the temperature sensor configuration described in [3] above, the insertion portion of the second housing has a groove on its outer surface that extends in the direction of insertion into the concave portion. This allows the temperature sensor to be manufactured by pre-injecting a filler into the concave portion of the first housing and then inserting the housing and the insertion portion of the second housing into the concave portion, while embedding the housing in the filler and allowing the filler to escape into the groove of the insertion portion. As a result, it is possible to suppress the retention of air bubbles and other particles in the filler that may affect the response performance of the temperature sensor. Therefore, the response performance of the temperature sensor can be improved.

[0046] [4] In the temperature sensor (1) described in [1] above, The first housing (40) is, It has a wall portion (41, 45) on which one side is the temperature measuring surface and the other side faces the storage space (46a), Temperature sensor (1).

[0047] In the temperature sensor configuration described in [4] above, one surface of the wall of the first housing is the temperature sensing surface, and the other surface of the wall faces the storage space. This allows heat to be quickly transferred from the object being measured to the filling material in the storage space via the temperature sensing surface when the temperature sensor is actually used. Thus, the response performance of the temperature sensor can be improved.

[0048] [5] In the temperature sensor (1) described in [1] above, The aforementioned containment (13) is It is a molded product having a predetermined molded shape. Temperature sensor (1).

[0049] In the temperature sensor configuration described in [5] above, the housing into which the temperature-measuring element is embedded is a molded product having a predetermined molded shape. In other words, the housing is not formed by the conventional fluid immersion method, but is formed using a mold designed to have a predetermined molded shape. As a result, variations in the shape of the housing are reduced compared to the conventional method. Therefore, the housing can be accurately formed to have a shape suitable for measuring the temperature of, for example, a gas or liquid to be measured. Thus, the response performance of the temperature sensor can be improved.

[0050] [6] The temperature sensor (1) described in [5] above, The molded shape of the housing (13) is It has a shape with an outer surface composed of multiple faces. Temperature sensor (1).

[0051] According to the temperature sensor configuration described in [6] above, the housing has a molded shape with an outer surface composed of multiple faces. In this case, for example, if a work jig or the like comes into contact with the boundary between adjacent faces, stress concentration may occur in this area, potentially causing deformation of the housing. However, since the housing is housed inside the housing, deformation of the housing can be properly suppressed even if the housing has such a molded shape. Therefore, the temperature sensor can perform temperature measurement as designed. [Explanation of Symbols]

[0052] 1. Temperature sensor 11. Thermistor element (temperature measuring element) 12 terminals 13 containment units 20 Housing 30 Resin housing (second housing) 31 Insertion part 34 Groove 40. Metal casing (first housing) 41 Small diameter section (wall section) 45 Bottom wall (wall section) 46 Concave part 46a Storage space 50 Filler

Claims

1. A temperature sensor comprising a temperature measuring element, a housing in which the temperature measuring element is embedded and housed, and a housing having a storage space for housing the housing, The aforementioned housing is The device comprises a first housing having a concave portion inside that defines the storage space and a temperature-measuring surface on the outside that will come into contact with the object to be measured; a second housing assembled to the first housing and closing the opening of the concave portion; and a filler material that fills the storage space and fills the gap between the housing and the first housing. The thermal conductivity of the material constituting the second housing is lower than that of the material constituting the filler. Temperature sensor.

2. A temperature sensor according to claim 1, The temperature measuring element is further provided with terminals that are connected to the temperature measuring element and extend from the housing, The terminals are in contact with the filler material. Temperature sensor.

3. In the temperature sensor according to claim 2, The preceding 2 housing is, It has an insertion portion that holds the terminal and is inserted into the recessed portion to close the opening, The aforementioned insertion portion is The outer surface of the insertion portion has a groove that extends in the direction of insertion into the concave portion. Temperature sensor.

4. In the temperature sensor according to claim 1, The first housing is, It has a wall portion on which one side is the temperature measuring surface and the other side faces the storage space. Temperature sensor.

5. In the temperature sensor according to claim 1, The aforementioned housing is It is a molded product having a predetermined molded shape. Temperature sensor.

6. A temperature sensor according to claim 5, The molded shape of the housing is, It has a shape with an outer surface composed of multiple faces. Temperature sensor.

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