JPS5942661Y2 - Liquid level detection device in a tank in a vehicle - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a device for detecting the liquid level in a fuel tank, mainly a fuel tank, in a vehicle.

Generally, a vehicle's fuel tank is equipped with a remaining fuel level detection device, and when the fuel contained in the tank falls below a certain level, it notifies the driver of the situation and prompts the driver to refuel. However, with conventional models, the sensors and floats are directly immersed in the liquid, so when the vehicle drives on rough, unpaved roads, the liquid level ripples and the lamp flashes, making it difficult to accurately check the remaining fuel level. If the vehicle cannot be detected and the vehicle turns, starts, or stops, the fluid level will fluctuate, and the fluctuating state will be reported via the sensor. It is not possible to accurately determine the remaining amount.

Therefore, this idea was devised to solve the above problem. Even if the liquid level in the tank ripples or fluctuates, the effect on the sensor is reduced, and the system can be used regardless of road conditions or driving conditions. The present invention provides a liquid level detection device that detects and detects a state of decrease in liquid.

FIGS. 1 and 2 show an embodiment of this invention, and 1 is a fuel tank in which the required amount of fuel f is accommodated. The case 2 of A is vertically immersed in the fuel f, and the bottom wall of the case 2 is provided with a liquid inlet hole 2a, and the upper part of both side walls is provided with an air vent hole 2b. A sensor 3 such as a thermistor or a reed switch with a float is disposed at the center of the inner side via an upright support plate 4 whose width is smaller than the thickness of the case 2a. The gap between the case 2 and the sensor 3 is filled with a porous filter member 5 such as open-cell foam, glass wool, steel wool, etc., except for the conductor part above the sensor 3.
A part of the liquid enters the case 2 through the liquid inlet hole 2a of the case 2, penetrates the filter member 5, and surrounds the sensor 3, and the liquid level is equal to the level of the fuel f outside the case 2 when the vehicle is stationary. matches.

The detection unit A is connected to a display circuit I that connects a pilot lamp t in the driver's seat via a terminal 6 on the mounting end plate.

Based on the above configuration, the ignition switch S is closed, the vehicle is running, and when the vehicle enters a rough road, the fuel f in the fuel tank 1 is
Even if it ripples violently as shown, the detection unit)
The fuel f that has entered the case 2 of A is blocked from the outside by the peripheral wall of the case 2 and is held by the porous filter member 5, so it remains constant without being directly affected by the ripples on the outside. Therefore, when the fuel f reaches a predetermined level, the sensor 3 accurately detects this state, and the pilot lamp t is activated.
lights up.

Furthermore, even if the liquid level of the fuel f changes rapidly when the vehicle turns, starts, or stops, the fuel f in the case 2 is retained in the filter member 5 and flows through the inlet hole 2a in the bottom wall. Since it is connected to the outside, the outflow is delayed in response to fluctuations, and the liquid level is maintained at a constant level.

Therefore, when the fuel f in the tank 1 falls below a certain level, the sensor 3 correctly detects this state, and the pilot lamp t lights up to notify the driver.

Note that this invention is not limited to detecting fuel in a fuel tank, but can also be applied to detecting the liquid level in an oil tank or the like.

As described above, in this invention, a porous filter member is interposed between the sensor and the casing in a device that detects the liquid level in the tank by suspending the casing with a sensor installed inside the tank earthen wall. Therefore, even if the liquid level in the tank ripples or changes suddenly due to driving on rough roads, turning, starting, stopping, etc., the liquid that has entered the detection device will be retained in the filter member. It is possible to always present an undisturbed liquid level without being affected by external ripples or rapid level fluctuations, and it is possible to accurately detect a certain level of liquid remaining. It can be produced on the floor.

[Brief explanation of the drawing]

Figure 1 is a vertical sectional view of an embodiment of this invention, and Figure 2 is its
- Sectional view along the X-ray. 1...fuel tank, 2...case, 2
a...Liquid inflow hole, 2b...Air vent hole, 3...Sensor, 4...Support plate,
5... Filter member, 6... Terminal, l
...Display circuit.

Claims (1)

[Scope of utility model registration request] In a device that detects the liquid level in a tank 1 by suspending a casing 2 with a sensor 3 disposed therein from the tank upper wall 1a, a porous filter member 5 is interposed between the sensor 3 and the casing 2. A liquid level detection device in a tank in a vehicle.