JPH0526713A - Level gage for vehicle - Google Patents

Abstract

PURPOSE:To obtain a level gage for a vehicle wherein the indication of a meter shows little change and is stable not only at the time of a sudden start, a sudden stop or a suddenn turn, but also on a long upward or downward slope. CONSTITUTION:A level gage for a vehicle, which is constructed by combining a catch-in cross coil movable magnet type meter 1 with a time-limiting circuit making and breaking a power source intermittently at prescribed time intervals, is equipped with a first time-limiting circuit 2 making and breaking the power source intermittently at a period whereat the cross coil type and movable magnet type meter 1 can operate at the minimum in ordinary running, in particular, a second time-limiting circuit 3 making and breaking the power source intermittently at a period whereat the cross coil type and movable magnet type meter 1 can operate at the minimum at the time of stopping (or at a prescribed speed or below, and a vehicle speed determining circuit 4 determining a vehicle speed and selecting and changing over one of the first time-limiting circuit 2 and the second time-limiting circuit 3 corresponding to the vehicle speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle liquid level gauge capable of stably measuring the liquid level of a fuel tank of a vehicle such as an automobile.

[0002]

2. Description of the Related Art As a conventional liquid level gauge for vehicles, a needle-type crossed coil type movable magnet type instrument and a predetermined period (time interval)
In combination with a timed circuit that intermittently turns on and off the power, the liquid level temporarily changes due to sudden start / stop / turning of the vehicle.
Even when the resistance value of the liquid level detector changes, there is a device in which the power supply of the liquid level indicator is intermittently interrupted at a predetermined cycle by a time circuit to reduce and delay the instruction fluctuation by the interruption time.

However, there is a problem that this liquid level gauge for vehicles is not effective when the resistance value of the liquid level detector changes for a long time, such as when the vehicle is stopped on a slope.

[0004]

A problem to be solved by the invention is that a combination of a conventional needle-type crossing coil type movable magnet type instrument and a timed circuit for intermittently turning on and off the power supply at a predetermined cycle (time interval) If the resistance value of the liquid level detector changes for a long period of time, such as when the vehicle is stopped on a slope, a wrong instruction may be given.

[0005]

SUMMARY OF THE INVENTION A first aspect of the present invention is a liquid level gauge for a vehicle, comprising a needle-type crossed coil type movable magnet type instrument 1 and a time circuit for intermittently turning on and off a power supply at a predetermined time interval. , The first timed circuit 2 for intermittently turning on and off the power supply at a cycle in which the cross coil type movable magnet type instrument 1 can be operated at a minimum at the time of normal traveling, and the cross coil type movable magnet type instrument 1 is set to the minimum when the vehicle is stopped (or below a predetermined speed). A second time-limit circuit 3 for connecting and disconnecting the power supply in a cycle in which a limit operation is possible, and the first time-limit circuit 2 or the second time-limit circuit 3 for judging the vehicle speed and corresponding to the vehicle speed.
It is provided with a vehicle speed determination circuit 4 for selecting and switching any of the above.

The second aspect of the present invention is directed to a first time limit circuit 12 in which the ratio (DUTY) of the power source connection time to the cutoff time is increased in response to an increase in vehicle speed, and when the vehicle is stopped (or below a predetermined speed). The cross-coil movable magnet type instrument 1 is formed by combining a second time circuit 3 for connecting and disconnecting the power supply at a cycle in which it can operate at a minimum.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an embodiment of the first invention will be described with reference to FIGS. 1 and 3. Reference numeral 1 is a needle-type crossing coil type movable magnet type instrument, and 2 and 3 are for supplying electric power to the crossing coil type movable magnet type instrument 1. In the first and second time limit circuits, the first circuit 2 is used during normal traveling, and the second time limit circuit 3 is used when the vehicle is stopped (or below a predetermined speed). The meter 1 is configured to switch the power supply on and off at the minimum operable cycle. A vehicle speed determination circuit 4 has a function of determining the vehicle speed and selecting and switching between the first time limit circuit 2 and the second time limit circuit 3 in accordance with the vehicle speed. Note that, as shown in FIG. 3, when the vehicle is stopped (or below a predetermined speed), the power supply is intermittently connected to the power supply for a time T ₁ when a switch (not shown) is inserted, and then T ₂ , T or T ₃ , T ₄ is repeated in the cycle. The ratio of the power supply connection time to the disconnection time (DUTY) is set to the minimum value at which the instrument 1 can be operated at a predetermined speed or lower, but when it exceeds the predetermined speed, it is raised stepwise at a stroke, and thereafter the vehicle speed is increased. It is set to a constant value regardless of the increase of.

The second invention will be described. As shown in FIG. 2, the second time limit circuit 3 is the same as that of the first time invention, but the first time limit circuit 12 increases the vehicle speed. According to the above, the ratio (DUTY) of the power supply connection time to the cutoff time is increased.

The operation of the first invention is as follows.
By providing two time limit circuits, the instrument 1 is stable with a small change in the finger pointing not only for sudden start / stop / turn, but also for long uphill / downhill trips. There is no mistake. When the first invention is applied, the vehicle suddenly starts, and when the speed exceeds a predetermined speed, if the liquid level fluctuation is not stable even after switching to the first time limit circuit 2, the ratio of the power supply connection time to the cutoff time (DUTY) May be too large, and the pointer of the instrument 1 may fluctuate greatly. For this state, the ratio of the power supply connection time of the first time circuit 2 to the cutoff time (DUT
The second invention in which Y) is continuously changed according to the vehicle speed is effective, and the pointer of the instrument 1 is stable.

[0010]

Since the present invention is constructed as described above,
In addition to sudden start, sudden stop, and sharp turn, the instrument 1 is stable with little finger change even on long ascents and descents.

[Brief description of drawings]

FIG. 1 is a device configuration diagram showing an embodiment of a first invention.

FIG. 2 is a device configuration diagram showing an embodiment of the second invention.

FIG. 3 is a state diagram showing a cycle example of power supply interruption / interruption of the time-limit circuit of the first invention.

FIG. 4 is a state diagram showing the relationship between the vehicle speed and the ratio of the power source connection time to the interruption time of the time limit circuit of the first invention.

FIG. 5 is a state diagram showing the relationship between the vehicle speed and the ratio of the power supply connection time to the power supply cutoff time of the time limit circuit of the second invention.

[Explanation of symbols]

1 Crossing coil type movable magnet type instrument 2 First timed circuit 3 Second timed circuit 4 Vehicle speed judgment circuit 12 First timed circuit of the second invention

Claims (2)

[Claims] 1. A liquid level gauge for vehicles, comprising a needle type crossed coil type movable magnet type instrument (1) and a timed circuit for intermittently turning on and off a power source at a predetermined time interval, the crossed coil type movable magnet type during normal traveling. The first timed circuit (2) for connecting and disconnecting the power supply at the minimum operable period of the instrument (1), the minimum operable period of the cross coil type movable magnet type instrument (1) at a stop (or below a predetermined speed) Second to turn the power on and off with
Of the time limit circuit (3) and the vehicle speed, and the vehicle speed determination circuit (4) for selecting and switching either the first time limit circuit (2) or the second time limit circuit (3) according to the vehicle speed. )
A liquid level gauge for vehicles. 2. A first time circuit (12) for increasing a ratio of a power source connection time to a cutoff time according to an increase in vehicle speed, and a cross coil type movable magnet type instrument when the vehicle is stopped (or below a predetermined speed). A liquid level gauge for vehicles, which comprises a combination of a second time circuit (3) for intermittently turning on and off the power supply in a cycle in which (1) can be operated at a minimum.