JP2003139621A - Temperature sensor and its fitting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a resin molded part 80 from coming off cut of a case 10. SOLUTION: This temperature sensor is provided with a cylindrical case 10 whose one end is stopped up, and a temperature detecting element 21 which is arranged in the case 10 and detects a temperature. The case 10 has a protrusion 11 which protrudes towards its periphery, and a part comprising the detecting element 21 and the protrusion 11 in the case 10 is filled with resin, and the molded part 80 is formed. Consequently, the molded part 80 is prevented from coming off cut of the case 10, by the locking between the protrusion 11 and the molded part 80, since the molded part 80 is formed also inside the protrusion 11 of the case 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor for detecting a temperature by a temperature detecting element arranged in a case and a mounting structure thereof.

[0002]

2. Description of the Related Art In a conventional temperature sensor of this type, a temperature detecting element is arranged in a cylindrical case whose one end is closed, and a resin is filled in the case to hold the temperature detecting element.

[0003]

However, in the conventional temperature sensor, the diameter of the tubular portion of the case is constant when a gap is created between the metallic case and the resin molded portion due to the difference in thermal expansion. , The resin mold part might come out of the case.

The present invention has been made in view of the above points, and it is an object of the present invention to prevent the resin mold portion from coming out of the case.

[0005]

In order to achieve the above object, according to the invention as set forth in claim 1, a cylindrical case (10) having one end closed and a temperature detected by being arranged in the case (10). In the temperature sensor including the temperature detecting element (21), the case (10) has a convex portion (11) that is convex toward the outer periphery, and the temperature detecting element (21) and the convex portion () are formed in the case (10). 11) is filled with resin to form a resin mold portion (80).

According to this, since the resin mold portion is also formed on the convex portion of the case, it is possible to prevent the resin mold portion from coming out of the case due to the engagement between the convex portion and the resin mold portion.

According to the second aspect of the invention, the temperature detecting element (2
1) two element-side conductors (30), two external conductors (70) connected to the element-side conductor (30) in the case (10), an element-side conductor (30) and an external conductor (7
0) to prevent contact between the two connections with the holder (5
0) and the holder (50) is characterized in that the sectional shape in the direction perpendicular to the axial direction thereof is S-shaped.

By the way, for example, when water penetrates into the case through a gap formed between the case and the resin mold portion, the water may cause a short circuit between the two connecting portions. Then, a holder having an S-shaped cross section and an E
Comparing with the letter-shaped holder, the S-shaped holder is
Since the creepage distance L between the two connecting portions becomes long (see FIG. 5), there is an advantage that it is difficult to cause a short circuit when water or the like enters.

Further, comparing an S-shaped holder and an 8-shaped holder in cross-sectional shape, in the case of the 8-shaped holder, the space in which the conductor wire is arranged communicates with the outside only at its axial end surface. On the other hand, in the case of the S-shaped holder, the space in which the conducting wire is arranged communicates with the outside not only in the axial end face but also in the side face, so that the S-shaped holder has a space to accommodate the conducting wire in the resin. Has the advantage that it can easily enter.

According to a third aspect of the present invention, there is provided a temperature sensor mounting structure for mounting the temperature sensor according to the first or second aspect to another member by a bracket (90), wherein the bracket (90) is a case ( It is characterized by having a fitting part (93) into which the convex part (11) of 10) is fitted.

According to this, since the convex portion of the case fits into the fitting portion of the bracket, the bracket and the case can be accurately positioned.

The reference numerals in parentheses of the above means indicate the correspondence with the specific means described in the embodiments described later.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention shown in the drawings will be described.

FIG. 1 is a sectional view showing the overall structure of the temperature sensor 1 according to the present invention, FIG. 2 (a) is a front view of the holder 50 of FIG. 1, and FIG. 2 (b) is a left side surface of FIG. 2 (a). Fig. 2 (c) is a right side view of Fig. 2 (a), Fig. 2 (d) is A- of Fig. 2 (b).
It is sectional drawing which follows the A line.

The temperature sensor 1 is used, for example, to detect the temperature of the fuel supplied to the engine of an automobile.

The temperature sensor 1 is provided with a bottomed cylindrical metal case 10, and a convex portion 11 which is convex toward the outer periphery (outer radial direction) is formed on the cylindrical portion of the case 10 by bulging. There is.

A thermometer 20 is arranged on the side of the bottom wall 12 in the case 10, and the thermometer 20 has a thermistor (corresponding to a thermometer element) 21 to which two element-side conducting wires 30 are connected.
Are embedded in the shell-shaped insulator 22 made of glass having electric insulation. Thermistor 21
Is mainly composed of ceramic or silicon semiconductor, and its resistance value changes according to temperature. The element-side conductive wire 30 is a single wire covered with an insulating tube.

The element-side conductive wire 30 extends through a protective tube 40 (described later in detail) into a holder 50 (described later in detail). The element-side conductive wire 30 is connected to the external conductive wire 70 in the holder 50 by a metallic connector 60. The external conducting wire 70 is a stranded wire covered with an insulating tube, and a metal terminal (not shown) is connected to an end of the external conducting wire 70.

The protective tube 40 is made of an electrically insulating ceramic (for example, aluminum oxide type, silicon magnesium type, forsterite) in a cylindrical shape.
It has two through holes 41 into which the two element-side conductive wires 30 are inserted (separately). Further, the protective tube 40 is hardened together with the insulator 22 in a state where the element-side conductive wire 30 is passed through the through hole 41, whereby one end of the protective tube 40 is hermetically coupled to the insulator 22.

The holder 50 is made of an electrically insulating resin (for example, nylon), and its concrete structure is shown in FIG.

In FIG. 2, the holder 50 has two spaces 51 in which the element-side conductor 30 and the connector 60 are arranged.
And two through holes 52 into which the external conductor wire 70 is inserted. On each side surface of the holder 50, one slit-shaped side surface opening 53 is formed along the axial direction of the holder 50, and the side surface opening 53 forms a space outside the side surface of the holder 50 and a space 51. Are in communication. Then, in the range where the side surface opening 53 is formed, the cross-sectional shape of the holder 50 in the direction perpendicular to the axial direction is S-shaped.

As shown in FIG. 1, in the two spaces 51 and the two through holes 52 of the holder 50, the element-side conductive wire 30,
One set of the connector 60 and one set of the external conducting wire 70 are arranged, whereby the two of the element side conducting wire 30 and the external conducting wire 70 are arranged.
It is designed to prevent contact between two connections.

Then, the temperature detector 20, the element-side conductor 30, the protective tube 40, the holder 50, the connector 60, and the external conductor 70.
1 is integrated as shown in FIG. 1, the integrated product is inserted into the case 10, and then a resin having electric insulation (for example, epoxy resin) is insert-molded to form a resin mold portion 80. The temperature sensor 1 shown in FIG. 1 is completed. In addition, the resin of the resin mold portion 80 is the thermometer 20.
The outer peripheral portion and the portion including the convex portion 11 are filled.

FIG. 3 shows the bracket 90, and FIG. 4 shows a state in which the temperature sensor 1 is mounted on the bracket 90. 3A is a front view of the bracket 90, and FIG.
3B is a left side view of FIG. 3A, and FIG.
It is a right view of (a).

The bracket 90 is formed by pressing a thin metal plate, for example, and as shown in FIG. 3, a through hole 91 into which a screw member (not shown) is inserted, and the temperature sensor 1.
Holding portion 92 having an arcuate cross section for holding
And a slit-shaped notch portion (corresponding to a fitting portion) 93 formed in the intermediate portion of the.

As shown in FIG. 4, the temperature sensor 1 is inserted into the holding portion 92 of the bracket 90, and at this time, the bracket 9 is inserted.
The convex portion 11 of the temperature sensor 1 is fitted in the notch 93 of 0. Then, for example, a bracket 90 is attached to a flange of a fuel pump mounted in a fuel tank (not shown), and the temperature of the fuel is detected by the temperature sensor 1.

In this embodiment, since the resin mold portion 80 is also formed on the convex portion 11 of the case 10, the resin mold portion 80 is engaged by the convex portion 11 and the resin mold portion 80.
Can be prevented from coming out of the case 10.

Further, in this embodiment, since the convex portion 11 of the case 10 fits into the notch portion 93 of the bracket 90,
The bracket 90 and the case 10 can be accurately positioned.

Further, the holder 50 of this embodiment has an S-shaped cross-section in the direction perpendicular to the axial direction in the range where the side opening 53 is formed. And FIG.
In the E-shaped holder 50 shown in FIG. 5B as a comparative example, the two side surface opening portions 53 are both located on one side surface of the holder 50, while as shown in FIG. S
In the character-shaped holder 50, the side surface opening portions 53 are located on the one side surface and the other side surface of the holder 50. Therefore, the S-shaped holder 50 has the element side conductive wire 30 and the external conductive wire 70.
The creepage distance L between the two connection parts becomes long, and there is an advantage that short-circuiting does not easily occur when water or the like enters.

On the other hand, holders 50 and 8 having an S-shaped cross section
Comparing with a letter-shaped holder, in the case of an 8-shaped holder,
The space in which the conductors 30, 70 and the connector 60 are arranged communicates with the outside only through the axial end face of the holder, whereas in the case of the S-shaped holder 50, the conductors 30, 70 and the connector 60 are arranged. Since the space 51 communicates not only with its axial end surface but also with the side surface through the side surface opening 53, the S-shaped holder 50 has an advantage that the resin can easily enter the space 51.

(Other Embodiments) In the above embodiment, the convex portion 11 of the temperature sensor 1 is fitted into the cutout portion 93 of the bracket 90, but instead of the cutout portion 93, the bracket 90 is replaced. A convex portion (corresponding to a fitting portion) having the same shape as the convex portion 11 of the temperature sensor 1 is formed on the holding portion 92, and the convex portion 11 of the temperature sensor 1 is fitted to the convex portion of the bracket 90. Good.

Further, in the above embodiment, the thermistor is used as the temperature detecting element, but the temperature detecting element is not limited to the thermistor, and various temperature detecting elements such as a temperature measuring resistance element and a thermocouple may be adopted.

Further, in carrying out the present invention, the present invention may be applied to a temperature sensor for detecting the temperature of various liquids, the temperature of a fluid or the temperature of a solid, not limited to the temperature of the fuel.

[Brief description of drawings]

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

2 is a diagram showing the holder 50 of FIG. 1. FIG.

FIG. 3 is a view showing a bracket 90.

4 is a diagram showing a state in which the temperature sensor 1 of FIG. 1 is mounted on a bracket 90 of FIG.

5A is a schematic diagram of the holder 50 of FIG. 1, and FIG. 5B is a schematic diagram of the holder 50 as a comparative example.

[Explanation of symbols]

10 ... Case, 11 ... Convex part, 21 ... Thermistor (corresponding to temperature detecting element), 80 ... Resin mold part.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shoji Ogawa             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO (72) Inventor Seisaburo Kawashima             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO (72) Inventor Takamasa Yoshihara             2-7-18 Machiya, Urawa City, Saitama Stock Association             Inside the Shibaura Electronics (72) Inventor, Fumichi Mashima             2-7-18 Machiya, Urawa City, Saitama Stock Association             Inside the Shibaura Electronics F-term (reference) 2F056 QF02 QF04 QF05

Claims (3)

[Claims] 1. A cylindrical case (10) with one end closed.
And a temperature sensor (21) arranged in the case (10) for detecting a temperature, wherein the case (10) has a convex portion (11) that is convex toward the outer periphery. A temperature sensor characterized in that a resin mold portion (80) is formed by filling resin in a portion including the temperature detecting element (21) and the convex portion (11) in the case (10). 2. The two element-side conductors (30) connected to the temperature detecting element (21) and the two outer conductors (7) connected to the element-side conductor (30) in the case (10).
0), the element side conductor (30) and the outer conductor (7)
0) to prevent contact between the two connections with the holder (5
0) and the holder (50) has an S-shaped cross-section in the direction perpendicular to the axial direction thereof. 3. A temperature sensor mounting structure for mounting the temperature sensor according to claim 1 or 2 to another member by a bracket (90), wherein the bracket (90) is a convex portion of the case (10). A mounting structure for a temperature sensor, comprising: a fitting portion (93) into which (11) fits.