JP3205221B2 - Manufacturing method of fluid temperature sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lubricating oil for various devices,
The present invention relates to a method for manufacturing a temperature sensor for measuring the temperature of a fluid such as cooling water or air.

[0002]

2. Description of the Related Art FIGS. 7 and 8 show conventional fluid temperature sensors. FIG. 7 is a side sectional view showing the temperature sensor, and FIG. 8 is a sectional view taken along line BB of FIG. In the figure, 1 is a thermistor as a temperature sensing element, 2a and 2b are a pair of terminals connected to both electrodes of the thermistor 1, and 3 is a temporary fixing for temporarily fixing and positioning the thermistor 1 and the terminals 2a and 2b. The members 3a and 3b are convex portions provided on both sides of the temporary fixing member 3, 4 is a waterproof connector incorporating the terminals 2a and 2b, 5 is an exterior molding resin, and a casing of the waterproof connector 4 and A bracket 5a for mounting the entire temperature sensor is integrally formed. Reference numeral 6 denotes an adhesive sealant applied to the entire circumference of a part of the temporary fixing member 3. Next, FIG. 9 is a cross-sectional view showing an exterior mold for a conventional temperature sensor, wherein 7 is a mold for forming the inside of the waterproof connector 4, and 7a and 7b are provided at the inner end of the mold 7. A pair of square holes into which the ends of the terminals 2a and 2b constituting the connector are inserted, and a mold 8 and 9 arranged so as to sandwich the mold 7 and forming the exterior of the temperature sensor and the outer shape of the connector; Reference numeral 10 denotes a gate disposed at a central portion on the opposite side of the mold 7.

Next, a method of manufacturing a conventional fluid temperature sensor will be described. In FIG. 8, the thermistor 1 is connected to terminals 2a and 2b, and is temporarily fixed by a temporary fixing member 3 formed by insert molding, and a subassembly is made. Next, the sub-assembly is covered with the exterior molding resin 5, and at the same time, the waterproof connector 4 and the bracket 5a are formed. This type of fluid temperature sensor generally requires the temperature sensing element to be inserted deeply into the fluid to be measured so as not to be affected by the temperature of the mounting portion. Therefore, the sub-assembly has an elongated shape and poor rigidity. Therefore, at the time of exterior molding, the exterior molding die 8 and the exterior molding die 8 and the exterior assembly die 5 are prevented from falling or moving even when receiving the inflow pressure of the exterior molding resin 5.
It is necessary to position and fix in 9. for that reason,
In the exterior molding, the tips of the terminals 2a and 2b are inserted into and fixed to the square holes 7a and 7b of the mold 7, and the projections 3a and 3a of the temporary fixing member 3 are fixed by the exterior molds 8 and 9.
3b is fixed and inserted. Therefore, since the protrusions 3 a and 3 b of the temporary fixing member 3 are in close contact with the exterior mold dies 8 and 9, the projections 3 a and 3 b are exposed outside without being covered with the exterior mold resin 5. Although the exterior molding resin 5 is molded in close contact with the temporary fixing member 3, in general, a slight gap is easily formed at the interface between the separately molded molding resins, and the convex portion 3 a of the temporary fixing member 3 is generally formed. , 3b and the exterior mold resin 5 cannot maintain airtightness. Therefore, by applying an adhesive sealant 6 over the entire circumference of a part of the temporary fixing member 3 on the connector 4 side from the convex portions 3a and 3b, the interface between the temporary fixing member 3 and the exterior molding resin 5 is adhesively sealed, and the external From the connector 4 or from
The structure is such that water is prevented from entering the thermistor 1 and the terminals 2a and 2b. That is, in the manufacturing process of the conventional temperature sensor, the adhesive sealant 6 is applied to the entire circumference of a part of the temporary fixing member 3 by a manual operation or an application machine, and after the adhesive sealant is dried by a drying furnace or natural leaving, It is manufactured by a method of performing exterior molding.

[0004]

The conventional fluid temperature sensor is manufactured by the above-described method, but has the following problems. That is, the temporary fixing member 3 is not completely covered with the exterior molding resin 5 but has a structure in which the temporary fixing member 3 is partially exposed, that is, exposed at the convex portions 3a and 3b. In order to prevent water from infiltrating into the connector, it is necessary to bond and seal the interface. A method of applying an adhesive sealant 6 to the sub-assembly temporarily fixed by the temporary fixing member, drying it, and then performing exterior molding. Was adopted. For this reason, there is a problem that it takes time to dry the adhesive sealant, and it is difficult to produce the adhesive sealant on a continuous line, thereby increasing the cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it has been made possible to simplify the sealing structure, thereby enabling production on a continuous line in a short time and reducing the cost. And a method for manufacturing a fluid temperature sensor.

[0006]

According to a method of manufacturing a fluid temperature sensor according to the present invention, a temperature sensing element and a pair of terminals are temporarily fixed with a temporary fixing member to form a subassembly, and the temporary fixing member has a concave portion or a concave portion. A protrusion is provided, and a sub-assembly support portion having a shape to be fitted to the concave portion or the protrusion is provided at a portion forming the inside of the connector of the exterior mold die. By positioning and fixing, the inclination and movement due to the inflow pressure of the molding resin during molding are suppressed to a small extent, so that the subassembly is not exposed except inside the waterproof connector, and the interface between the temporary fixing member and the exterior molding resin is formed. Even without the use of an adhesive sealant, a sealing effect is produced just by fitting a mating connector that has waterproof properties. It is obtained by allow.

According to the second aspect of the present invention, a pair of concave portions are provided on the inner surface of the temporary fixing member, and a pair of sub-assembly supporting convex portions corresponding to the concave portions are provided on a mold forming the inside of the connector. Things.

According to the third aspect of the present invention, one concave portion having a non-circular cross section is provided at the center of the temporary fixing member.
1 corresponding to the above-mentioned concave portion is formed in a mold forming the inside of the connector
The sub-assembly support projections are provided.

[0009]

In the method for manufacturing a fluid temperature sensor according to the first aspect of the present invention, since the interface between the sub-assembly temporarily fixed by the temporary fixing member and the exterior molding resin is only in the waterproof connector, the adhesive sealant is used. Since the sealing effect can be obtained without using, the operation of applying and drying the adhesive sealant can be abolished, so that production can be performed in a continuous line in a short time, and the cost can be reduced.

In the method for manufacturing a fluid temperature sensor according to the second aspect of the present invention, the subassembly is firmly fixed at the time of molding the outer package, so that stable molding can be performed.

According to the third aspect of the present invention, since the cross-sectional shape of the sub-assembly support portion can be reduced, the thermal insulation between the temperature sensing portion and the bracket portion is good, and the temperature sensor has high accuracy. Can be manufactured.

[0012]

【Example】

Embodiment 1 FIG. FIG. 1 is a sectional view showing a fluid temperature sensor according to one embodiment of the present invention, and FIG. 2 is a view of FIG. In the figure, 1 is a thermistor, 2a and 2b are a pair of terminals connected to both electrodes of the thermistor 1, and 3 is a temporary fixing for temporarily fixing and positioning the thermistor 1 and the terminals 2a and 2b by insert molding. It is a member. Next, 11a and 11b are a pair of concave portions provided symmetrically on both sides of the temporary fixing member 3.
Is a waterproof connector incorporating the terminals 2a and 2b, 5 covers the member temporarily fixed by the temporary fixing member 3,
It is an exterior molding resin that partially forms the casing of the waterproof connector 4. Next, FIG. 3 is a cross-sectional view showing an outer mold for the temperature sensor, 12 is a mold for forming the inside of the waterproof connector 4, and 12 a and 12 b are the molds 1.
A pair of convex subassembly support portions projecting from the front end of the second subassembly correspond to the concave portions 11a and 11b. Reference numerals 8 and 9 denote molds for forming the exterior of the temperature sensor and the external shape of the connector, 10 denotes a gate, and 7a and 7b denote square holes of the die 12.

Next, a method of manufacturing the temperature sensor will be described. A subassembly including the thermistor 1 and the terminals 2a and 2b and temporarily fixed by the temporary fixing member 3 having the concave portions 11a and 11b is formed.
2b is inserted into the square holes 7a and 7b of the mold 12 and fixed, and two concave portions 11a and 11b provided on both sides of the temporary fixing member 3 are provided in a pair of holes provided in the mold 12. Convex subassembly support portions 12a and 12b
The sub-assembly is positioned and fixed in the exterior mold by this fitting. Perform molding. At this time, the convex portions 12a and 12b of the one exterior molding die 12 are not exposed to the exterior of the exterior molding resin 5 unlike the conventional projections 3a and 3b, and are waterproof type connectors formed of the exterior molding resin. It is composed only of Further, the gate 10, which is an injection port of the exterior molding resin, is arranged in the horizontal direction and near the center with respect to the projections 12a and 12b of the exterior molding die 12 for fixing the member temporarily fixed by the temporary fixing member 3. In this case, the exterior molding resin easily flows around the member temporarily fixed by the temporary fixing member.

Next, the airtight structure of the temperature sensor manufactured as described above will be described. The subassembly temporarily fixed by the temporary fixing member 3 is entirely covered with the exterior molding resin except for the inside of the waterproof connector formed of the exterior molding resin. In other words, except for the inside of the waterproof connector formed of the exterior molding resin, since there is no interface between the resins serving as passages for water, oil, air, etc., the waterproof connector formed of the exterior molding resin has waterproof properties. The airtightness of the temperature sensor can be achieved only by fitting the mating connector.

Embodiment 2 FIG. 4 and 5 show a second embodiment of the present invention. FIG. 4 is a sectional view showing a temperature sensor.
6 is a cross-sectional view of FIG. 4 as viewed from the C side, and FIG. 6 is a cross-sectional view illustrating an exterior mold for the temperature sensor. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. In the first embodiment, the sub-assembly is fitted so as to be sandwiched between the two sub-assembly support portions 12a and 12b on both sides, and the sub-assembly is positioned and fixed in the exterior mold by this fitting. When the sub-assembly supporting portion is provided at two places on both sides of the sub-assembly as described above, it is necessary to increase the cross-sectional shape of the temperature sensor. If the cross-sectional shape of the temperature sensor is large, there is a problem that thermal insulation between the temperature sensing unit and the bracket unit deteriorates, causing an error in temperature measurement. Therefore, in the present embodiment, one concave portion 13 is provided at the center of the temporary fixing member 3, and the mold sub-assembly supporting portion 14 corresponding to the concave portion 13 is provided in the mold 12 forming the inside of the connector. The sub-assembly support portion 14 was fitted so as to be inserted into the concave portion 13 of the temporary fixing member, and the outer sub-assembly was positioned and fixed by this fitting during exterior molding. The cross-sectional shapes of the concave portion 13 and the sub-assembly support portion 14 of the temporary fixing member 3 are non-circular, so that they have the effect of preventing rotation. According to this structure, the first embodiment
In addition to obtaining the same sealing effect as described above, the cross-sectional shape of the sub-assembly supporting portion can be reduced, so that a highly accurate temperature sensor can be manufactured.

In the above embodiment, the provisional fixing member 3 is provided with a concave portion and the corresponding mold 12 is provided with a convex portion. However, the relationship between these concave and convex portions may be reversed.

[0017]

As described above, according to the present invention, a seal can be formed by a very simple method of merely fitting a waterproof type mating connector to a waterproof type connector formed on a temperature sensor. In this case, the adhesive sealing material application step and the drying step can be eliminated, and the production can be performed in a continuous line in a short time as compared with the conventional manufacturing method, and the cost can be reduced.

According to the second aspect of the present invention, the sub-assembly is sandwiched from both sides and firmly fixed at the time of exterior molding, so that there is an effect that the molding is stabilized.

According to the third aspect of the present invention, since the cross-sectional shape of the sub-assembly support portion can be reduced, the thermal insulation between the temperature sensing portion and the bracket portion is good, and a highly accurate temperature sensor can be obtained. .

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a temperature sensor according to Embodiment 1 of the present invention.

FIG. 2 is a view of the temperature sensor of FIG.

FIG. 3 is a cross-sectional view of an outer mold for the temperature sensor according to the first embodiment of the present invention.

FIG. 4 is a side sectional view showing a temperature sensor according to a second embodiment of the present invention.

5 is a view of the temperature sensor of FIG.

FIG. 6 is a cross-sectional view of an exterior mold for a temperature sensor according to Embodiment 2 of the present invention.

FIG. 7 is a side sectional view showing a conventional temperature sensor.

8 is a cross-sectional view of the conventional temperature sensor taken along the line BB of FIG.

FIG. 9 is a cross-sectional view showing an exterior mold for a conventional temperature sensor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Thermistor, 2a, 2b terminal, 3 temporary fixing member, 4 waterproof connector, 5 exterior molding resin, 7
a, 7b square hole, 8, 9, exterior mold, 10 gate, 11a, 11b, 13 recess provided in temporary fixing member, 12 exterior mold, forming inside of connector, 12a, 12b, 14 sub-assembly support Department.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-45517 (JP, A) JP-A-1-97822 (JP, A) JP-A-62-167129 (JP, U) JP-A-6-167129 (JP, U) 29010 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01K 7/00 G01K 7/22 G01K 1/08

Claims (3)

(57) [Claims] 1. Manufacture of a fluid temperature sensor including a temperature sensing element, a pair of terminals connected to both electrodes of the temperature sensing element, and a waterproof connector for connecting the terminal to an external measurement circuit. A method, comprising forming a sub-assembly in which the temperature sensing element and the terminal are fixed by a temporary fixing member, and forming the sub-assembly by covering the sub-assembly with an exterior mold. A convex portion is provided, and a sub-assembly supporting portion having a shape to be fitted to a concave portion or a convex portion of the temporary fixing member is provided in a portion forming the inside of the connector of the exterior molding die. By positioning and fixing the sub-assembly by fitting, it is possible to reduce the inflow pressure of mold resin during molding. A method of manufacturing a temperature sensor for a fluid, wherein the sub-assembly is prevented from being exposed except inside the waterproof connector, while the tilting and the movement of the sub-assembly are kept small. 2. A temporary fixing member having a pair of recesses on an inner surface thereof.
On the other hand, a portion forming the inside of the connector of the exterior mold is provided with a pair of convex sub-assembly supporting portions corresponding to the pair of concave portions, and the pair of convex sub-assembly supporting portions serves as the temporary fixing member. The sub-assembly is positioned and fixed by the fitting so as to sandwich the pair of recesses.
A method for manufacturing the fluid temperature sensor according to the above. 3. A temporary fixing member having a concave portion having a non-circular cross section at the center thereof, and a convex sub-portion corresponding to the concave portion having a non-circular cross section is formed in a portion forming the inside of the connector of the exterior molding die. An assembly support portion, wherein the convex sub-assembly support portion is inserted into and fitted to the concave portion of the temporary fixing member, and the sub-assembly is positioned and fixed by the fitting. Item 7. A method for manufacturing a fluid temperature sensor according to Item 1.