JPH0547820U - Bottom reference type liquid level detector - Google Patents

Abstract

(57) [Abstract] [Purpose] To simplify the structure of the liquid level detection device that determines the position of the float base point with respect to the bottom of the tank, reduce the number of parts, and enable stable detection. [Structure] A support arm 2 is extended from a plate portion 1 to be attached to a tank, a sliding resistance type sensor unit 5 is fixed at an intermediate position thereof, and the support arm 2 itself is coiled on the upper side of the sensor unit 5 of the support arm 2. A spring part 8 wound around the tank is formed, and a free end 4 for contacting the bottom surface of the tank is formed.
Is urged by the elastic force of the spring portion 8. [Effect] The support arm 2 itself can be provided with an angle adjusting function and a spring function, and the number of components of the entire liquid level detection device can be reduced to simplify the assembly work.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention particularly relates to a liquid level detection device mounted on a vehicle, and more particularly to a bottom reference type liquid level detection device equipped with a detection position adjusting mechanism of a sensor unit based on the bottom face of a tank.

[0002]

[Prior Art]

 The fuel tank of a vehicle is equipped with a float type liquid level detection device that has a sliding resistance type sensor unit that detects the remaining amount of the fuel. Especially, the tank bottom is made thinner due to the weight reduction of the tank. That is, a so-called bottom-referenced liquid level detection device has been proposed in consideration of changes due to distortion of the bottom position caused by changes in remaining weight and temperature and changes in the shape of various tanks.

For example, as shown in Japanese Utility Model Laid-Open No. 63-73632 and Japanese Utility Model Laid-Open No. 61-1134, a structure in which a sensor unit is biased in the vertical direction, or Japanese Utility Model Laid-Open No. 60-193421 and actual Japanese Utility Model Publication No. As disclosed in Japanese Laid-Open Patent Publication No. 62-123522, there has been proposed a structure in which the support arm and the float position are interlocked with each other, and the support arm is brought into contact with the bottom surface of the tank to adjust the angle.

[0004]

[Problems to be solved by the device]

 However, the former has a problem that the vertical movement mechanism is complicated and the mounting position of the unit on the tank is limited.In the latter, the extension direction of the support arm can be set appropriately, so that the mounting position on the tank is free. However, even in the above proposed structure, the number of parts is still increased, and the structure is complicated compared to the unit structure without the bottom reference mechanism, and the cost is inevitably increased. That is, even in the latter structure, the sensor unit is rotatably mounted on the mounting plate part to the tank by bracket support, the support arm is fixed to the sensor unit, and the coil spring is mounted on the bracket part. Since the liquid level detection device was completed for the first time, there were problems that the number of parts was large and the work of assembling them was complicated and the device price eventually became expensive.

[0005]

[Means for Solving the Problems]

 According to the present invention, a support arm is extended and formed directly from a mounting plate portion to a tank, a sliding resistance type sensor unit is fixed at an intermediate position, and the support arm itself is wound in a coil shape on the upper side of the sensor unit of the support arm. The feature is that the turned spring part is provided.

[0006]

【Example】

 As shown in FIG. 1, a supporting arm 2 made of metal (for example, hard steel wire) is fixed to the plate portion 1 for mounting in the mounting hole portion of the tank by welding or appropriate fixing means such as bolts or caulking, and the tip thereof. A collar 3 made of resin is attached to the side and is extended with a predetermined length so as to form a free end 4 which comes into contact with the bottom surface of the tank.

The support arm 2 is made of a long rod-shaped metal material and is formed to have elasticity to some extent, and a slide resistance type sensor unit 5 is appropriately provided at a midway of its extension such as welding or caulking. It is fixed by the fixing means. The sensor unit 5 has a sliding resistor made up of a winding resistor and a printed resistor board inside a metal housing, and an electric signal corresponding to the liquid level is generated at the contact position of the sliding contact that comes into contact with the resistor. It has a well-known structure to generate. That is, a swing arm 7 having a float 6 attached to its tip is rotatably attached to the sensor unit 5, and the floating contact (floating position) of the float 6 (liquid The rotation angle of the swing arm 7 is converted according to the change in resistance value.

Further, a spring portion 8 wound in a coil shape is formed in the upper portion of the support arm 2 above the sensor unit 5 in advance when the support arm 2 itself is produced. Although the coil shape is four windings here, the number of windings may be freely selected according to the elastic modulus of the material of the support arm 2 or its thickness and the diameter of the coil. Then, the angle of the support arm 2 may be changed around the spring portion 8.

In the embodiment, a low-range warning level detection sensor 9 composed of a thermistor is provided at the tip of the support arm 2, and the connection cord 10 is entwined with the support arm 2 and drawn around to the plate section 1. It is connected to the electrical connection terminal 11 of the plate portion 1 together with a connection cord for electrically extracting the resistance value change of the sliding resistance type sensor unit 5.

With the above structure, the bottom-referenced liquid level detection device is completed. As described above, the conventional angle detection part, biasing spring, and support arm of this type of detection device have a plurality of parts. Since all of them are integrally formed by the support arm 2, the number of parts is extremely small, and therefore the assembling work of the detection device is also simplified.

The position of the present invention will be described with reference to the detection state when it is attached to the tank. As shown in FIG. 2, the plate portion 1 is attached to the attachment hole portion of the tank in a sealed state. As a result, the position of the sensor unit 5 of the support arm 2 is fixed while the free end 4 of the support arm 2 is in contact with the bottom surface of the tank. That is, when the swing arm 7 restricted by the rotation restricting piece of the sensor unit 5 within a predetermined rotation range is located at the lowermost point restriction position, that position is set with respect to the contact free end 4 of the support arm 2. Move in the confirmed state.

As a result, even if the bottom surface of the tank changes vertically, the contact free end 4 of the support arm 2 is urged downward by the elastic force of the spring portion 8 and the lower side of the support arm 2 is centered on the spring portion 8. Since the angle is adjusted, the contact free end 4 is always in contact with the bottom surface of the tank, and the sensor unit 5 including the float 6 that is interlocked with it is also given a constant detection base point based on the bottom surface of the tank. Therefore, the liquid level detection accuracy is stable and stable with respect to the bottom surface of the tank.

[0013]

As described above, in the detection device according to the present invention, the support arm itself can have the spring function and the angle adjustment function, and the number of parts is extremely small, which facilitates the assembly work of the device. It is possible to obtain the economic effect that the bottom reference function can be satisfied without increasing the cost of the device, and the number of parts is reduced by providing the supporting arm itself with various necessary functions. The size and characteristics of the entire device can be made stable without the need for precision in attachment. Especially, by designing the support arm itself with high precision, it has the advantage that it is suitable for stable mass production, and that assembly and adjustment with other parts is also extremely simple.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the device of the present invention.

FIG. 2 is an explanatory view showing a state in which the device of the present invention is attached to a tank.

[Explanation of symbols]

 1 Plate Part 2 Support Arm 4 Abutment Free End 5 Sliding Resistance Type Sensor Unit 6 Float 7 Swing Arm 8 Spring Part

Claims (1)

[Scope of utility model registration request] 1. A plate portion fixed to a wall surface of the tank,
A support arm extending from the plate portion to the bottom surface side of the tank, a sliding resistance type sensor unit fixed to an intermediate position of the support arm, a swing arm rotatably supported by the sensor unit, The support arm has a float attached to the tip side of the arm, and the support arm has a tip end extending downward from the sensor unit and having a contact free end with which the bottom surface of the tank abuts, and the support arm itself is provided between the sensor unit and the plate portion. A bottom-referenced liquid level, comprising a spring portion wound in a coil shape, wherein the angle of the support arm is adjusted around the spring portion in accordance with the contact of the free end with the bottom surface of the tank. Detection device.