JPH0328340Y2 - - 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 electrical 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 play or the frame 2 may come off from the frame 1. These phenomena end up causing inaccuracies in liquid level displays, warning displays, etc. based on the sensor position shift, and also cause abnormal noises within the tank.

The present invention was developed in view of the above points, and is a sensor mounting shaft for a liquid level detection device that can firmly mount the sensor mounting shaft to the frame without wobbling and always provide stable and accurate liquid level detection operation. The purpose is to provide a support structure for

[Means for solving problems]

In order to achieve the above object, the present invention has a structure in which the shaft is screwed onto the frame in a direction perpendicular to the axial direction of the shaft,
A screw that comes into contact with the shaft to prevent the shaft from moving in directions perpendicular to both the shaft axial direction and the screwing direction is inserted, and the shaft tip formed on the frame and bent at a substantially right angle is inserted to tighten the shaft. a first restriction part that prevents movement of the shaft in the axial direction of the screw; and a second restriction part that is formed on the frame and comes into contact with the shaft to prevent movement of the shaft in the direction in which the screw is threaded. It is characterized by what it did.

〔Example〕

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

The frame 1 is an integrally molded product of synthetic resin, and has a hanging wall 1b on the lower surface of the substrate 1a.
A shaft insertion hole 1c parallel to the substrate 1a is formed in the center of the upper part of the shaft insertion hole 1c, a screw threaded part 1d and a locking wall 1e perpendicular to the threaded part 1d are formed below the shaft insertion hole 1c, and a cross section U is formed below these. A letter-shaped locking portion 1f and a projecting wall 1g above the locking portion 1f are provided.

The tip of the shaft 2 is bent into an L-shape, and this tip 2b is inserted into the shaft insertion hole 1c.
, the shaft body 2 is sandwiched between the locking wall 1e and the screw 4 on the screw threaded part 1d, and furthermore, one side of the lower part comes into contact with the projecting wall 1g, and the shaft body 2 is inserted into the U-shaped locking part 1f. It is inserted.

The shaft 2 mounted in this manner is prevented from moving in the axial direction (Y-axis direction in the figure) by fitting the shaft tip 2b into the shaft insertion hole 1c, and the distance between the shaft and the shaft insertion hole 1c is prevented. The movement of the screw 4 in the insertion direction (X-axis direction in the figure) is prevented by the engagement of the inlet portion and the side walls 1h of the U-shaped locking portion 1f, and the locking wall 1e, the screw 4, the projecting wall 1g, U
The rear wall 1i of the letter-shaped locking portion 1f prevents movement in a third direction (Z-axis direction in the figure) orthogonal to both the axial directions of the shaft and the screw.

Therefore, the screw insertion hole 1c is a first restriction portion A that prevents movement in the shaft axial direction, and the entrance portion of the shaft insertion hole 1c and both side walls 1h of the U-shaped locking portion 1f are second restriction portions. The screw 4 is attached to the locking wall 1e, the projecting wall 1g, and the inner wall 1i of the U-shaped locking portion 1f.
At the same time, movement in the third direction is restricted.

In addition, when attaching shaft 2 to frame 1,
Insert the tip of the shaft 2 from below the frame as shown by the arrow in Figure 1, and insert it into the shaft insertion hole 1c.
After inserting it into the holder, the screw 4 may be screwed on. Since the entrance of the screw insertion hole 1c has an elliptical shape that is elongated in the shaft axis direction (Y-axis direction) as shown in FIG. 1, the shaft can be easily inserted.

In the above embodiment, the direction of the force applied to the screw 4 is
Since the only direction (Z-axis direction) is perpendicular to both the screw tightening direction (screw axial direction) and the axial direction of the shaft 2, 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 embodiment, and FIG. 4 is an exploded perspective view of the same embodiment.

In this embodiment, the frame 1 is a press-molded product of metal material, and includes a shaft insertion hole 1c, a screw threaded part 1d, a locking wall 1e, a projecting wall 1g, and a U-shaped locking part 1f formed in the frame 1. etc., at the same time as press forming, or by welding, screwing, etc.
established in

However, the positioning action for the shaft 2 is exactly the same as in the first embodiment.

[Effect of idea]

The present invention is as described above, and the screw is designed to receive force only in one direction orthogonal 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 a main part of a first embodiment of the present invention, Fig. 2 is an exploded perspective view of the first embodiment, Fig. 3 is a sectional view of a main part of a second embodiment, and Fig. 4 is a sectional view of a main part of a second embodiment. FIG. 5 is an exploded perspective view of the embodiment. FIG. 5 is an exploded perspective view of the conventional example. DESCRIPTION OF SYMBOLS 1... Frame, 2... Shaft, 3... 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 sensor for liquid level detection is attached to the tip of a shaft fixed to a frame, the sensor is screwed onto the frame in a direction perpendicular to the axial direction of the shaft and comes into contact with the shaft. A screw that prevents the shaft from moving in a direction perpendicular to both the axial direction of the shaft and the screwing direction is inserted, and the tip of the shaft formed on the frame and bent at a substantially right angle is inserted and moved in the axial direction of the shaft. A sensor mounting shaft comprising a first restricting part that prevents movement of the shaft, and a second restricting part that is formed on the frame and comes into contact with the shaft to prevent movement of the shaft in the direction in which the screw is screwed. supporting structure.