JPH05180438A - Device for sensing remained volume of oil in fuel tank - Google Patents

Abstract

PURPOSE:To provide a device for sensing a remained volume of oil in a fuel tank having a high general applicability capable of accommodating for any type of fuel tanks having different heights. CONSTITUTION:A device for sensing a remained volume of oil in a fuel tank is comprised of a pressure sensor 3 arranged at a discharging part of a fuel tank 1, a meter 9 varied in response to an output of the pressure sensor 3 and a variable resistor 13 connected in series with the meter 9. At the initial time of using this device, the variable resistor 13 adjusts the oscillation of the meter 9 in such a way that it shows the position of 'full volume' when the fuel tank is full of fuel. Accordingly, the remained volume of oil can be displayed linearly at the output of the pressure sensor 3 whatever type of fuel tank may be applied without having any relation with the height and shape of the fuel tank.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a residual oil amount detecting device for a separately installed fuel tank.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, a residual oil amount detecting device for a fuel tank has mainly used the buoyancy of a float. Pointer 103 provided at the tip
Alternatively, an arm 1 that is composed of a variable resistor or the like and that interlocks with a float 101 that moves up and down according to the oil level of the fuel tank.
The residual oil amount is detected by changing the resistance value of the pointer 103 or the resistor via 02.

[0003]

However, in the above-mentioned conventional structure, the movable range of the pointer 103 as the display unit and the sliding range of the variable resistor cannot be unnecessarily wide due to the structure of the mechanism. Limited to a given range.
Therefore, the operating ranges of the arm 102 and the float 101 connected to the display section are also restricted. In other words, since the operating range of the float 101 from "full" to "empty" varies depending on the size (height) of the fuel tank, it is necessary to set the movable range of the pointer with respect to the vertical movement of the float 101 each time, which is versatile. Only the fuel tank and the pair of residual oil amount detection devices could be provided. In addition, when a conventional mechanical type is used to detect the residual oil amount with versatility regardless of the size of the fuel tank, a complicated mechanical mechanism for amplifying or damping the vertical movement of the float. Was required, and a very high precision was required for the adjustment method.

The present invention solves the above-mentioned problems, and makes it possible to easily detect the residual oil amount in any fuel tank simply by adjusting the variable resistance provided in the display unit according to the size of the fuel tank. The purpose is to

[0005]

In order to achieve the above object, the present invention provides a pressure sensor at the outlet of a fuel tank,
This pressure sensor and a display that operates according to the output of the pressure sensor and a variable resistor for changing the current flowing through the display are provided, and display according to the output of the pressure sensor that changes depending on the size of the fuel tank. The "full capacity" position of the device can be arbitrarily adjusted by a variable resistor.

[0006]

According to the present invention, by adjusting the variable resistor connected in series to the indicator, the present invention can arbitrarily set the "full" position of the indicator according to the size of the fuel tank, that is, the oil level height. Therefore, it is possible to detect the residual oil amount with versatility regardless of the size of the fuel tank.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, the system configuration will be described with reference to FIG.
Reference numeral 1 is a fuel tank installed outdoors, 2 is a filter, and a pressure sensor 3 is provided at the outlet of the filter by branching with a T-shaped tube. Reference numeral 4 is a lead wire connecting the pressure sensor 3 and the indicator 6, reference numeral 5 is a pipe for supplying fuel from the fuel tank 1 to the combustor 8, and reference numeral 6 is an indicator, which corresponds to the output of the pressure sensor 3 as shown in FIG. It is composed of a meter 9 for displaying the tank residual oil amount and a lamp 11 for giving a notice of refueling when the tank residual oil amount becomes a predetermined value or less. 7 is a power cord, 8 is a combustor installed indoors, 9 is a meter, 11 is a refueling notice lamp, 12
Is a power lamp.

Next, the circuit configuration will be described with reference to FIG.
A variable resistor 13 is connected in series to the meter 9 and sets the deflection of the meter 9 to the “full” position according to the output of the pressure sensor 3 when the fuel tank 1 is full. 14, 1
Reference numerals 5 and 16 are resistors for setting a reference value for issuing a notice when the output of the pressure sensor 3 drops below a predetermined value. Reference numeral 17 is a comparator, and 18 is an oscillating circuit for blinking display of the refueling notice lamp 11. Reference numeral 19 denotes a diode for compensating for the meter shake when the pressure sensor 3 has a low output.

FIG. 4 is a graph showing the output characteristics of the pressure sensor 3, in which the output voltage changes substantially linearly according to the oil level height (H) of the fuel tank 1, that is, the pressure change. In the above configuration, first, with the fuel tank 1 being full, the variable resistor 13 incorporated in the display 6 is adjusted so that the deflection of the meter 9 is at the "full" position. For example, when the size of the fuel tank 1 is H = 450 mm, an output voltage of 3.1 V is generated in the full state, so that the meter 9 has a current showing a full scale at 3.1 V. Adjust the variable resistor 9. After the above adjustment, as long as the size of the fuel tank 1 does not change, the output voltage changes according to the oil level height (H), that is, the state of the residual oil amount, the swing of the meter 9 changes, and the residual oil amount changes. Can be detected. When the oil level height (H) decreases and the output voltage of the pressure sensor 3 becomes equal to or lower than the reference voltage set by the resistors 14, 15 and 16, the output of the comparator 17 is inverted and the oscillation circuit 18 starts operating. , Refueling notice lamp 11 starts blinking, and fuel tank 1
Notify you that the amount of residual oil in the tank has decreased.

Next, the size of the fuel tank 1 is H = 600 m.
The case of attaching to m. Even if the size of the fuel tank changes, the adjustment operation is performed in the same manner as described above, and the variable resistor 13 is adjusted with the fuel tank 1 being full so that the swing of the meter 9 is set to the "full" position. To do. When H = 600 mm, 3.9 V is generated as the output voltage of the pressure sensor 3, so the variable resistor 13 is adjusted so that the meter 9 has a full-scale current at 3.9 V. After that, the deflection of the meter 9 is changed by the output of the pressure sensor 3 which changes according to the oil level height,
It is possible to detect the change in the residual oil amount linearly.

As described above, by keeping the fuel tank full, and adjusting the deflection of the meter to full scale with the variable resistor, the state of the residual oil amount can be linearly adjusted regardless of the size of the fuel tank. It can be detected at the same time, and if it falls below a predetermined level, it is possible to give a notice of refueling with a lamp.

In the above embodiment, the method of displaying the residual oil amount by the meter is described, but a digital display by using A / D conversion is also possible.

[0013]

As described above, the fuel tank residual oil amount detecting device of the present invention detects the residual oil amount in the fuel tank by using the pressure sensor and displays the meter by the output thereof. With the configuration in which a variable resistor is connected in series, the fluctuation of the meter can be adjusted arbitrarily according to the output state of the pressure sensor, so the residual oil amount can be detected regardless of the size of the fuel tank. It is possible to provide a highly versatile residual oil amount detection device that can handle even the above.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a residual oil amount detection device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram for detecting a residual oil amount in a fuel tank using the same device.

FIG. 3 is a front view showing a display unit of the apparatus.

FIG. 4 is a graph showing an output characteristic of a pressure sensor of the device.

FIG. 5 is a configuration diagram of a conventional residual oil amount detection device.

[Explanation of symbols]

 1 Fuel tank 3 Pressure sensor 6 Indicator 9 Meter 11 Refueling notice lamp 13 Variable resistor

Claims (1)

[Claims] 1. A fuel tank, and a pressure sensor which is disposed at the outlet of the fuel tank and linearly outputs a signal depending on the oil level.
In a residual oil amount detection device including an indicator that displays according to the output of the pressure sensor and an alarm circuit that issues a notice of refueling when the output of the pressure sensor reaches a predetermined value, a variable resistor is connected in series with the indicator. A fuel tank residual oil amount detection device in which the "full" display position of the above-mentioned indicator can be arbitrarily adjusted by connecting the above with the upper limit output value of the pressure sensor depending on the size of the fuel tank.