JPS5838466Y2 - Waterproof thermal sensor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in the internal structure of a waterproof thermal sensor.

Conventionally, in order to prevent deterioration of the heat-sensitive operating performance of waterproof thermal sensors, the internal chamber in which the electrode connection section and circuit section of the heat-sensitive actuator are located is generally made waterproof to shield it from the outside air. ing.

On the other hand, in order to fix the lead wires drawn out from the heat-sensitive actuating body, it is common to fill the internal chamber with an adhesive to provide the above-mentioned waterproof structure.

However, the conventional sensor structure requires a large amount of the adhesive for waterproofing and fixing the lead wires, which is uneconomical, and it also takes a long time to solidify uniformly, which impedes workability. This had the disadvantage of causing deterioration.

Particularly in recent years, when a sensor is equipped with an alarm indicator light and its circuit section is installed, the internal chamber becomes even larger and it becomes necessary to use a large amount of adhesive, so the above-mentioned drawbacks become more noticeable. ing.

On the other hand, a sensor disclosed in Japanese Utility Model Application Publication No. 51-98090 has been devised to solve the above-mentioned drawbacks.

This sensor is equipped with a waterproof cover that covers the lead wire extraction part and has a hole for the lead wire to pass through.The lead wire connected to the electrode of the sensor is pulled out through the hole, and the gap between the hole and the lead wire is filled with silicone. Rubber is filled from the inside and the waterproof cover is glued or welded to the base.

However, in such sensors, the interval (length) at which the lead wire is glued to the hole in the waterproof cover is short, and the lead wire covering has low adhesion, making it easy to remove the lead wire. It has new drawbacks.

The present invention was made in view of the above points, and aims to propose a sensor that uses a small amount of adhesive to provide waterproofness and the ability to remove lead wires, thereby eliminating the above-mentioned conventional drawbacks. It is something.

To achieve this objective, the present invention forms an annular recess surrounding the inner chamber of the sensor, fits a waterproof cover into the recess to form a so-called labyrinth structure, and bends the lead wire into the U-shape. The object of the present invention is to provide a sensor which is inserted through the recess and filled with an adhesive.

The present invention will be described below based on an embodiment shown in the drawings.

As shown in FIGS. 1 to 3, the sensor according to the present invention has an annular recess 1 surrounding an internal chamber R of the sensor formed in a base 2, and a lead drawn out from the internal chamber R into the recess 1. The wires 3, 3 are bent into a U-shape, a waterproof cover 4 is fitted, and the recess 1 is filled with adhesive A to make it waterproof.

To explain this in detail, the recess 1 is composed of a ring-shaped peripheral wall 5 and a partition wall 6 of the internal chamber R, and a plurality of protrusions 7, 7 are provided at appropriate positions on the peripheral wall 5.

This protrusion I is connected to the lead wire 3 drawn out from the internal chamber R.
However, as shown in FIG. 3, it functions as a rising portion for drawing out the recess 1 to the outside.

Additionally, the recess 1 is provided with a protrusion 8 along its peripheral wall 5, and the protrusion 8 is provided with the recess 1 on the cylindrical wall of the waterproof cover 4.
2 are engaged, the cover 4 is securely fitted, and its removal 75 is prevented.

The waterproof cover 4 is a cylindrical cap with a bottom that is fitted into the recess 1 to shield the inner chamber R of the sensor from the outside air. 10
, a cylindrical wall 1 having an outer diameter matching the inner diameter of the recess peripheral wall 5;
1 is formed.

A recessed line 12 for engaging the above-mentioned peripheral wall protruding line 8 is provided on the outer periphery of this cylindrical wall 11, and on the other hand, the above-mentioned collar 9 has notches 13, 13 for wire passage corresponding to the protruding part 7 of the recessed part 1. is provided.

When the waterproof cover 4 is fitted into the recess 1, a so-called labyrinth structure is formed, and as shown in FIG. It comes into contact with the upper end 5a of the peripheral wall 5, and by filling the recess 1 with adhesive A, which will be described later, the internal chamber R is completely waterproofed.

The lead wire 3 is drawn out from the internal chamber R through the recess 1, as shown in FIG.

To explain this in detail, the lead wire 3 is pulled out from the internal chamber R, applied to wire passage notches 14, 14 provided in the upper end portion 6a of the partition wall, and inserted into the recess 1, as shown in FIG. TeU
It is bent into a letter shape and guided to the outside through the protrusion 7.

The lead wire 3 drawn out in this manner is fixed by fitting the waterproof cover 4, and is further secured by being filled with the adhesive A.

That is, when the waterproof cover 4 is fitted into the recess 1, the lead wire 3 further protrudes, with the cutout 14 portion at the lower flange surface 10 of the waterproof cover 4 and the U-shaped bent portion at the lower end of the cylindrical wall 11. The rising portion from the section 7 is clamped and restrained by the flange notch 13, and has a U-shaped bent section, so that the adhesive A
The length of the lead wire buried in the lead wire can be increased, and therefore, the situation where the lead wire comes off due to the low adhesion of the lead wire due to exposure to radiation can be sufficiently avoided.

Note that the lead wire 3 may be provided with a knot in the vicinity of the notches 13 and 14 or may be wrapped around an arbitrary protrusion to prevent the lead wire from coming off.

As described above, by bending the lead wires 3, 3 drawn out from the internal chamber R into a U-shape, fitting the waterproof cover 4 into the recess 1, and filling the recess 1 with the adhesive A, the internal chamber can be opened. R waterproofing can be applied and the lead wire can be prevented from coming off.

Note that the adhesive A may be filled before or after the waterproof cover 4 is fitted.

As explained above, the present invention has a configuration in which an annular recess is formed around the inner chamber of the sensor, a waterproof cover is fitted into this to form a so-called labyrinth structure, and the recess is filled with adhesive. Therefore, the waterproof function can be achieved with a small amount of adhesive, and the lead wire inserted through the recess is bent into a U shape and has a large length buried in the adhesive, which prevents the lead wire from coming out. This has the effect of avoiding the

[Brief explanation of the drawing]

Fig. 1 is a front view of the sensor according to the present invention, Fig. 2 is a sectional view taken along line XX in Fig. 1, Fig. 3 is an internal structure diagram of the sensor according to the invention, and Fig. 4 is a diagram showing how the sensor fits into the base. FIG. 3 is an exploded view of the waterproof cover. 1... recess, 2... base, 3... lead wire, 4...
...Waterproof cover, 5...Peripheral wall, 5a...Top end, 6
...Partition wall, 6a...Top end, T...Protrusion, 8.
... Protrusion, 9... Tsuba, 10... Tatami lower surface, 11... Cylindrical wall, 12... Concave strip, 13° 14... Notch for wire passage, R... Internal chamber, A...Adhesive.

Claims (1)

[Scope of utility model registration request] An annular recess surrounding the internal chamber of the sensor is formed in the base, and a cylindrical wall of a waterproof cover is fitted into the recess to cover the internal chamber, and a lead wire drawn out from the internal chamber is covered with the waterproof cover. A waterproof thermal sensor characterized by being bent into a U-shape and having a waterproof structure by filling the recess with an adhesive.