JPH05266377A - Heat sensor and its manufacture - Google Patents

Abstract

PURPOSE:To improve working efficiency and assembling precision by simplifying the positioning of plural parts in assembling work in respect of a heat sensor using a semiconductor heat sensing element like a thermistor, etc., and its manufacture. CONSTITUTION:A printed board 4 is positioned to a main body 2 by the fitting of a positioning projection 10 and a positioning groove 11, and a back cover 6 assembled with a shield case 5 is positioned to the back side of the main body 2 by the fitting of the positioning projection 12 and the positioning groove 13. Further, an outer cover 1 is positioned to the lower side of the main body 2 by the fitting of the positioning projection 14 and the positioning groove 15, and in this positioned state, the back cover 6, the shield case 5, the printed board 4, the main body 2 and the outer cover 1 are fixed integrally by the screw joint of a fitting piece 8 to the back cover 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat sensor using a semiconductor thermosensitive element such as a thermistor and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, as a heat sensor of this type and a manufacturing method thereof, for example, the one disclosed in Japanese Patent Laid-Open No. 1-259494 is known. In this heat sensor, a printed circuit board with a heat sensitive element, a body for housing the printed circuit board, a cover for exposing the heat sensitive element of the printed circuit board mounted on the body to the outside, and a screw for the printed circuit board are provided. It has a structure provided with a middle cover which is interposed between the cover and the cover so as to penetrate the heat sensitive element for positioning and to prevent dust from entering.

[0003]

However, in such a conventional heat sensor, in the assembly of the body, the printed circuit board and the cover, the screw holes and the screw through holes formed in the respective bodies are aligned with each other. Since the screws are screwed together and fixed with, and the screwing work must be performed at the same time as the alignment, the assembly work is complicated.
In addition, there is a large variation in positioning due to the degree of screwing, and especially when trying to automate assembly work by a robot or the like, the work process is complicated, high positioning accuracy is required, and there is a problem that the yield of products decreases.

The present invention has been made in view of the above-mentioned problems of the prior art, and a heat sensor and a heat sensor for measuring the improvement of work efficiency and assembly accuracy by simplifying the positioning of a plurality of parts in the assembly work. It is intended to provide a manufacturing method.

[0005]

To achieve this object, the present invention is constructed as follows. The reference numerals in the drawings of the embodiments are also shown. First, the present invention is directed to an outer cover 1, a main body 2 integrally formed with a thermosensitive element 9 protruding outward, a printed circuit board 4 on which a sensor circuit is mounted, a shield case 5, a fitting metal fitting 8.
A heat sensor having an assembled structure in which a back cover 6 having the above is sequentially stacked is intended.

According to the invention of the heat detector having such a structure, the first positioning protrusion 10 is provided on either the back side of the main body 2 or the printed circuit board 4, and the other is fitted to the first positioning protrusion 10. A first positioning groove 11 for
The second positioning protrusion 12 is provided on one of the body 2 and the back cover 6.
And a second positioning groove 13 that fits into the second positioning projection 12 is provided on the other side, a third positioning projection 14 is provided on either one of the main body 2 and the outer cover 1, and a third positioning projection 14 is fitted on the other side. A matching third positioning groove 15 is provided, the first positioning protrusion 10 and the first positioning groove 11 are fitted to each other for positioning, and the printed circuit board 4 is assembled to the main body 2, and the second positioning protrusion 12 and the second positioning groove 13 are provided. Main body 2 in which printed circuit board 4 is incorporated by positioning by fitting with
Attach the back cover 6 incorporating the shield case 5 to the back side of the
Further, the third positioning protrusion 14 and the third positioning groove 15 are fitted to each other for positioning, and the outer cover 1 is assembled to the lower side of the main body 2. It is characterized by having a structure in which the lid 6, the shield case 5, the printed circuit board 4, the main body 2 and the outer cover 1 are integrally fixed.

The present invention also provides a method of manufacturing a heat sensor having such a structure, which comprises the following steps. [First Step] First Positioning Protrusion 10 and First Positioning Groove 1
The printed circuit board 4 is mounted on the main body 2 by positioning it by fitting with 1.
Temporarily assemble.

[Second Step] Second Positioning Protrusion 12 and Second
The back cover 6 incorporating the shield case 5 is temporarily assembled on the back side of the main body 2 in which the printed circuit board 4 is incorporated by positioning by fitting with the positioning groove 13. [Third process] Third positioning protrusion 14 and third positioning groove 1
The outer cover 1 is temporarily assembled on the lower side of the main body 2 after being positioned by fitting with 5.

[Fourth Process] The back cover 6, the shield case 5, the printed circuit board 4, the main body 2 and the outer cover 1 in the temporarily assembled state are integrally fixed by screws.

[0010]

According to the heat detector of the present invention having such a structure, the main body and the printed circuit board, the main body and the back cover, and the main body and the outer cover are temporarily assembled by fitting the positioning projections and the positioning grooves. It is possible to perform accurate positioning in the state, and after temporary assembly, the whole assembly can be assembled and fixed to one while maintaining a correct positional relationship through a fixing operation of the fitting metal fitting to the back cover with a tapping screw.

Therefore, the positioning in the assembling work can be easily and accurately performed, and the positioning can be performed in the temporary assembly prior to the screw fixing work, which facilitates the application of the automatic assembly by the robot or the like and stabilizes the high assembly accuracy. Obtainable.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an exploded view showing an embodiment of a heat sensor of the present invention. 1, the heat detector of the present invention is constructed by stacking an outer cover 1, a main body 2, an O-ring 3, a printed circuit board 4, a shield case 5 and a back cover 6 in this order from the bottom. A thermistor 9 is integrally formed in the lower center part of the main body 2. In addition, the shield case 5 has a contact piece 1
6 is erected so that it can be electrically contacted with the ground pattern of the print base 4.

Further, the back cover 6 is provided with a pair of terminal pins 17, and a pair of fittings 8 are fixed to the upper portions of the terminal pins 17. A through hole 18 is opened in a position of the shield case 5 facing the terminal pin 17 of the back cover 6, and a pin hole opened downward in a portion of the printed circuit board 4 facing the terminal pin 17 through the through hole 18. A terminal receiver (not shown) which is fitted on the pin 19 by pushing the tip of the pin is provided.

In the present invention, the heat detector comprising the outer cover 1, the main body 2, the printed board 4, the shield case 5 and the back cover 6 has the following positioning structure. First, the main body 2 is provided with the first positioning protrusions 10 at two locations inside the main body 2, as is apparent from the state shown in FIG. Corresponding to the first positioning protrusions 10 of the main body 2, first positioning grooves 11 are formed at two locations on the side surface of the printed circuit board 4 of FIG. Therefore, by fitting the first positioning groove 11 of the printed circuit board 4 into the first positioning protrusion 10 of the main body 2, both can be positioned.

Positioning members 20 are provided on both sides of the main body 2.
As is clear from FIG. 2, the positioning member 20 is formed with a second positioning groove 13 that opens upward. Corresponding to the second positioning groove 13 of the main body 2, second positioning protrusions 12 are integrally formed at two positions on the side surface of the back cover 6 of FIG. Therefore, the second body 2
By fitting the positioning groove 13 and the second positioning protrusion 12 of the back cover 6, both can be positioned at a prescribed position.

Further, a third positioning protrusion 14 is provided at the base of the positioning member 20 of the main body 2. This third
Corresponding to the positioning protrusions 14, as is apparent from the outer cover 1 shown in FIG. 3 in which the inside can be seen, third positioning grooves 15 are formed at two locations inside the outer cover 1. Therefore, by fitting the third positioning protrusion 14 of the main body 2 into the third positioning groove 15 on the inner side of the outer cover 1, both can be positioned at the specified positions.

As described above, according to the present invention, the positioning projection and the positioning groove for positioning the printed circuit board 4, the back cover 6 and the outer cover 1 with respect to the main body 2 have a specified positional relationship. The positional relationship between the printed circuit board 4, the back cover 6 and the outer cover 1 with respect to the main body 2 can be uniquely determined by fitting the positioning protrusion and the positioning groove.

Next, the process of assembling the heat detector of the present invention shown in FIG. 1 will be described in detail. Back cover 6 when assembling the heat sensor
The shield case 5 is built in and fixed in advance inside, and the fitting 8 is also fixed in advance on the opposite side of the terminal pin 17. In addition, electrical components forming a sensor circuit are mounted on the printed circuit board 4 in advance.

In this state, first, in the first step of the assembly work,
The first positioning groove 11 on the side surface of the printed circuit board 4 with respect to the first positioning protrusion 10 on the inner side of the main body 2 shown in FIG.
And the printed circuit board 4 is temporarily assembled to the main body 2. Subsequently, in the second step, the back cover 6 in which the shield case 5 and the fitting 8 are assembled in advance is assembled with the O-ring 3 fitted in the upper portion of the main body 2. At this time, the second positioning groove 1 of the positioning member 20 overhanging the side surface of the main body 2
3 is fitted to the second positioning protrusion 12 on the side surface of the back cover 6 to perform positioning and temporary assembly of both.

Subsequently, in the third step, the assembly of the main body 2, the O-ring 3, the printed circuit board 4, the shield case 5, the back cover 6 and the fitting 8 is assembled to the outer cover 1. At this time, the third positioning protrusion 14 at the bottom of the main body 2 is positioned in the third positioning groove 15 inside the outer cover 1 shown in FIG.
The outer cover 1, the main body 2,
The O-ring 3, the printed circuit board 4, the shield case 5, the back cover 6, and the fitting 8 are temporarily assembled.

Then, in the fourth step, as shown in FIG. 1, tapping screws are inserted into the through holes provided inside the outer cover 1 through the through holes 23 formed in the four overhanging portions 22 of the back cover 6. The main body 2, the O-ring 3, the printed circuit board 4, and the shield case 5, which are located between them, are integrally fixed by fastening the back cover 6 to the outer cover 1 by tightening while screwing.

As described above, according to the present invention, the printed circuit board 4, the back cover 6 and the outer cover 1 centering on the main body 2 are brought into a temporary assembled state in which the positioning groove and the positioning projection are fitted to maintain a prescribed positional relationship. Finally, the assembly can be performed by a simple operation of finally fixing the whole by using the tapping screw 7. In the above embodiment, the relationship between the positioning groove and the positioning protrusion for positioning the printed circuit board 4, the back cover 6 and the outer cover 1 with respect to the main body 2 is one of which is formed on the main body 2 side and the other is the printed circuit board 4,
It may be formed on the back cover 6 and the outer cover 1, and which of the positioning groove and the positioning protrusion is provided is not limited to the embodiment.

[0023]

As described above, according to the present invention,
Each of the printed circuit board, back cover, and outer cover for the main body can be accurately positioned in the temporarily assembled state by fitting the positioning protrusions and the positioning grooves between them, and positioning and final fixing work by screwing are separated. As a result, the alignment in the assembly work can be done easily and accurately.

[0024] Further, by performing the screw fixing finally after performing the positioning as the temporary assembly work, it is possible to easily apply the automatic assembly by the robot or the like and stably obtain a high assembly system. The yield can be improved.

[Brief description of drawings]

FIG. 1 is an exploded view showing an embodiment of the present invention.

FIG. 2 is an explanatory view showing the inside of the main body of FIG.

3 is an explanatory view showing the inside of the outer cover of FIG. 1. FIG.

[Explanation of symbols]

 1: Outer cover 2: Main body 3: O-ring 4: Printed circuit board 5: Shield case 6: Back cover 7: Tapping screw 8: Fitting metal fitting 9: Thermistor (heat sensitive element) 10: First positioning protrusion 11: First positioning Groove 12: Second positioning projection 13: Second positioning groove 14: Third positioning projection 15: Third positioning groove 16: Contact piece 17: Terminal pin 18: Opening hole 19: Pin hole 20: Positioning member 22: Overhanging piece 23 : Through hole

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[Procedure amendment]

[Submission date] December 16, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an exploded view showing an embodiment of a heat sensor of the present invention. 1, the heat detector of the present invention is constructed by stacking an outer cover 1, a main body 2, an O-ring 3, a printed circuit board 4, a shield case 5 and a back cover 6 in this order from the bottom. A thermistor 9 is integrally formed in the lower center part of the main body 2. In addition, the shield case 5 has a contact piece 1
6 is erected so that the ground pattern of the printed circuit board 4 can be electrically contacted.

Claims (2)

[Claims] 1. An outer cover (1), a main body (2) integrally protruding with a thermosensitive element (9), a printed circuit board (4) on which a sensor circuit is mounted, a shield case (5), and a fitting. In a heat sensor having an assembly structure in which a back cover (6) including (8) is stacked in order, a first positioning protrusion (on either the back side of the main body (2) or the printed circuit board (4). 10) and a first positioning groove (11) that fits in the first positioning protrusion (10) is provided on the other side, and a second positioning groove is provided on either the body (2) or the back cover (6).
A positioning protrusion (12) is provided, and a second positioning groove (13) that fits into the second positioning protrusion (12) is provided on the other side, and a second positioning groove (13) is provided on either one of the main body (2) and the outer cover (1). 3 locating protrusions (14) are provided and the other third
The third positioning groove (1) that fits into the positioning protrusion (14)
5) is provided, and the first positioning protrusion (10) and the first positioning groove (1) are provided.
The printed board (4) is positioned on the main body (2) by fitting the printed board (4) to the main body (2), and the printed board (4) is assembled by fitting the second positioning protrusion (12) and the second positioning groove (13). By positioning the back cover (6) incorporating the shield case (5) on the back side of the main body (2), and by fitting the third positioning protrusion (14) and the third positioning groove (15). The outer cover (1) is positioned on the lower side of the main body (2), and the back cover (6), the shield case (5), the printed circuit board (4) are fixed by screws in the positioned state.
A heat detector having a structure in which a main body (2) and an outer cover (1) are integrally fixed. 2. An outer cover (1), a body (2) integrally formed with a thermosensitive element (9) protruding outward, a printed circuit board (4) on which a sensor circuit is mounted, a shield case (5), and a fitting. (8), the first positioning protrusion (1) is provided on either the back side of the main body (2) or the printed circuit board (4).
0) is provided and the first positioning protrusion (10) is provided on the other side.
Is provided with a first positioning groove (11), and a second positioning protrusion (12) is provided on one of the main body (2) and the back cover (6) and the second positioning protrusion (12) is provided on the other. 12) is provided with a second positioning groove (13) to be fitted,
Furthermore, a third positioning protrusion (14) is provided on either one of the main body (2) and the outer cover (1), and a third positioning groove (15) that fits into the third positioning protrusion (14) is provided on the other. In the method of manufacturing a sensor having a structure provided, the first positioning protrusion (10) and the first positioning groove (1) are provided.
1) A first process of positioning by fitting with the main body (2) and temporarily assembling the printed circuit board (4), the second positioning protrusion (12) and the second positioning groove (1).
The shield case (5) is provided on the back side of the main body (2) in which the printed circuit board (4) is incorporated by positioning by fitting with 3).
Second step of temporarily assembling the back cover (6) incorporating the above, the third positioning protrusion (14) and the third positioning groove (1)
5) A third step of positioning by fitting with the main body (2) to temporarily assemble the outer cover (1), and the back cover (6) and the shield case (5) in the temporarily assembled state. A fourth step of integrally fixing the printed circuit board (4), the main body (2) and the outer cover (1) with screws.
A method of manufacturing a heat sensor, comprising: