JPH0320736Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a liquid level detection device used in devices such as vehicle fuel level gauges, and particularly relates to a support structure of a shaft to which a detection sensor is attached. .

[Problems to be solved by conventional techniques and ideas]

The conventional device will be explained with reference to FIG.

A frame 1 is fixed to a fuel tank or the like and is made of a press-molded metal material. Some parts (not shown) are attached to the frame 1, and a support shaft 2 for a liquid level detection sensor is fixed to the center of the frame 1.

The shaft 2 has a sensor 3 made of a thermistor fixed at its tip, and the middle part is bent as appropriate.
Two thin-walled portions 2a are provided at the opposite end,
The frame 1 is screwed into the screw hole 1a of the frame 1 by a screw 4 passing through the thin portion 2a.

In such a liquid level detection device, when the thermistor element is in the fuel liquid, self-heating does not proceed due to large heat dissipation, and the resistance value of the element is high. As fuel decreases and the element is exposed to the air, heat dissipation becomes smaller and self-heating rapidly progresses. Therefore, the electric resistance value of the element decreases, the circuit current increases, and a warning lamp etc. lights up. In the figure, what is wound around the shaft 1 is a lead wire 5 that connects the sensor 3 to a meter.

However, in the conventional device described above, when force is applied to the sensor 3 or the shaft 2 due to the liquid in the tank, the force in all directions is directly applied to the shaft fixing part of the screw 4 (tap-in screw).
There is a risk that the thin wall portion 2a of the shaft 2 may be deformed. Further, due to impact force and heat during assembly, the screws 4 may become loose, and as a result, the shaft 2 may become loose or may come off from the frame 1. These phenomena end up causing inaccuracies in liquid level displays, warning displays, etc. due to the misalignment of the sensor position, and also cause abnormal noises within the tank.

The present invention was developed in view of the above points, and is a shaft for mounting a sensor in a liquid level detection device, which allows the shaft for mounting the sensor to be firmly attached to the frame without wobbling, and always provides stable and accurate liquid level detection operation. The purpose is to provide support structures for

[Means for solving problems]

In order to achieve the above object, the present invention includes a screw that penetrates the shaft in a direction perpendicular to the axial direction of the shaft and is screwed onto the frame to prevent the shaft from moving in the shaft axial direction, and a screw that is formed on the frame and that is screwed onto the frame to prevent the shaft from moving in the shaft axial direction. a first regulating portion that is formed on the frame and that comes into contact with the shaft and prevents the shaft from moving in the axial direction of the screw; and a second restriction portion that prevents movement of the shaft.

〔Example〕

FIG. 1 is a sectional view of essential parts of the first embodiment, and FIG. 2 is an exploded perspective view.

The frame 1 is an integrally molded synthetic resin product, and a U-shaped locking portion 1 is provided at the center of the bottom surface of the substrate 1a.
b. Two hanging legs 1c, 1d on both sides, a screw threaded part 1e on one side of one hanging leg 1c, and a locking part with a U-shaped cross section at the connecting part of the two hanging legs 1c, 1d. 1
f respectively.

The shaft 2 has a thin wall portion 2a at its tip, and a screw insertion hole 2b is formed in the thin wall portion 2a.

As shown in FIG. 1, the shaft 2 has a thin end portion 2a and an intermediate shaft portion engaged with the U-shaped locking portion 1b and the U-shaped locking portion 1f, respectively. Then, the thin portion 2a is screwed onto the screw threaded portion 1e of the frame 1 by the screw 4 inserted through the screw insertion hole 2b.

The shaft 2 mounted in this manner is prevented from moving in the axial direction (Y-axis direction in the figure) by the screw 4, and is attached to both side walls of the U-shaped locking portion 1b and the U-shaped locking portion 1b. Movement in the screw insertion direction (X-axis direction in the figure) is prevented by both side walls of the portion 1f, and the inner wall of the U-shaped locking portion 1b and the curved wall of the U-shaped locking portion 1f;
Furthermore, the projecting wall formed on the upper part of the U-shaped locking portion 1f prevents movement in a third direction (Z-axis direction in the figure) perpendicular to both the shaft axis direction and the screw insertion direction. Ru.

Therefore, the screw 4 is a restricting part in the shaft axial direction, and both side walls of the locking part 1b and both sides of the locking part 1f constitute a first restricting part A in the screw insertion direction. The back wall, the curved wall of the locking portion 1f, and the protruding wall constitute a second regulating portion B in the third direction.

In addition, when attaching shaft 2 to frame 1,
It is sufficient to simply insert the tip of the shaft 2 into the frame as shown by the arrow in FIG. 1 and screw it in with the screw 4.

In the above embodiment, the direction of the force applied to the screw 4 is
The axial direction of shaft 2 (Y
(axial direction), there is little possibility that the screw 4 will loosen even if it receives some force.

FIG. 3 is a sectional view of the second practical example, and FIG. 4 is a perspective view of the same example.

In this embodiment, the frame 1 is a press-molded product of metal material. Therefore, the U-shaped locking portion 1b, U-shaped locking portion 1f, etc. in the first embodiment are fixedly formed on the frame 1 by means such as screwing or welding. Further, the threaded portion 1e, the projecting wall, etc. are integrally formed by press molding. The structure is the same as that of the first embodiment except that the materials of the frame 1, the regulating portions A, B, etc., and the molding method are different from those of the first embodiment. Therefore, the operation is also similar to that of the first embodiment.

In the first and second embodiments described above, the hole 2b through which the screw 4 is inserted is a circular hole, but it may be a notch with one side open as long as the movement of the shaft 2 in the axial direction can be restricted. .

[Effect of idea]

As explained above, in the present invention, force is applied to the screw only in one direction perpendicular to its axial direction. Therefore, there is little possibility that the screw will loosen or that the thin walled portion through which the screw is inserted will deform, and stable and reliable liquid level detection can be performed at all times.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of main parts of the first embodiment of the present invention, Fig. 2 is an exploded perspective view of the first embodiment, Fig. 3 is a sectional view of main parts of the second embodiment of the invention, Fig. 4 5 is an exploded perspective view of the second embodiment, and FIG. 5 is an exploded perspective view of the conventional example. DESCRIPTION OF SYMBOLS 1... Frame, 2... Shaft, 1... Sensor, 4... Screw, A... First regulating part, B... Second regulating part.

Claims (1)

[Claim for Utility Model Registration] In a liquid level detection device in which a liquid level detection sensor is attached to the tip of a shaft fixed to a frame, the sensor is screwed to the frame by penetrating the shaft in a direction perpendicular to the axial direction of the shaft. , a screw that prevents the shaft from moving in the shaft axial direction; a first regulating portion that is formed on the frame and comes into contact with the shaft to prevent the shaft from moving in the axial direction of the screw; A support structure for a shaft for mounting a sensor, comprising a second restricting part that comes into contact with the second restricting part and prevents movement of the shaft in a direction perpendicular to both the axial direction of the shaft and the axial direction of the screw.