JPS6232322A - Sensor for liquid level - Google Patents

Abstract

PURPOSE:To improve measuring accuracy of a liquid level and to lower the total height of a liquid-level sensor by constituting a float so as to move in an inclined direction with respect to a vertical direction to the liquid level. CONSTITUTION:When the liquid level is on the H level, the float 1 is situated near to the upper end part of a case 6 and a magnet 2 makes a reed switch 4a on. Further, when the liquid level is displaced to the L level, the float is moved in the inclined direction downward to the left to make a reed switch 4b on. Hereby, the H level and the L level are detected. In this way, since the float 1 is moved in the inclined direction from the vertical direction to the liquid level with respect to the vertical displacement of the liquid level, the quantity of movement of the float 1 becomes larger than the quantity of displacement of the liquid level and since the detection is performed by enlarging the quantity of displacement by that quantity, the measuring accuracy is improved. Further, since the magnet 2 is provided at the lower side of the float 1, a switch 4a which is long vertically can be provided in the case 6 at the lower side of the float 1 and the total height of the liquid-level sensor can be lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a liquid level sensor for detecting the amount of lubricating oil in an internal combustion engine with a reduced height.

(Prior Art) A liquid level sensor for detecting the amount of lubricating oil in an internal combustion engine is conventionally known (for example, Utility Model Application No. 103614/1983).
. FIG. 5 shows an example of this type of liquid level sensor, in which annular magnets 2a and 2b are attached to a cylindrical float 1, and flows 1 to 1 are connected to a vibrator. It is assembled so that it can freely slide in the vertical direction in FIG. 5 with 3 as an axis. Reed switches 4a and 4b are provided in the vibrator 3 at a height for detecting the liquid level, and are fixed by being filled with resin 5. The vibrator 3 has an upper end fixed to a positioning part 6a provided on the case 6, and a lower end fixed to a pedestal 7, and the case 6 is fixed to the pedestal 7 with screws 9. The pedestal 7 is screwed to a mounting seat 11 which is annularly connected to the oil pan 10 by welding or the like.

Inside the case 6, there is an opening 12a provided in the case 6.
The oil stored in the oil pan 10 enters through 12b and 12b. The openings 12a and 12b have a function of damping fluctuations in the oil level due to vehicle photography, engine vibration, etc. The oil level changes up and down due to the oil seal, and when it reaches H level as shown in Fig. 5, the reed switch 4a is closed by the magnetic force of magnet 2a, and when it reaches L level, it is closed by the magnetic force of magnet 2b. This is detected when the reed switch 4b closes. The on/off state of the reed switch 4a or 4b is taken out from the cord 14 and is used for warning display, etc.

(Problems to be Solved by the Invention) In such conventional liquid level sensors, when detecting the oil level in the oil pan of an engine, the difference in height between the H level and the L level is When the IQs is small, around IQs, there is a problem that measurement accuracy is difficult to obtain because it is impossible to distinguish between H level and L level.

Vehicles are often lowered to reduce air resistance while driving, but when lowering the vehicle height, the overall height of the engine must also be lowered accordingly. . As a result, the distance between the highest level of engine oil and the crankshaft becomes as small as possible. On the other hand, in order to detect the oil level without being affected by the tilt of the vehicle, it is desirable to provide a liquid level sensor in the center of the oil pan. From these viewpoints, it is necessary to reduce the overall height of the liquid level sensor so that it does not interfere with the crankshaft.

However, in the conventional liquid level sensor shown in FIG. 5, a magnet 2a is provided on the top of the float 1 in order to detect the H level, and a vertically elongated reed switch 4a is attached to the magnet 2a.
Since the pipe 3 is embedded in the pipe 3, the pipe 3 protrudes from the upper surface of the float 1, and the positioning part 6a for determining the position of the pipe 3 protrudes further upward. There is a problem that the overall height cannot be lowered.

(Purpose and Structure of the Invention) The present invention has been made in view of the above points, and aims to improve the accuracy of measuring the liquid level and reduce the overall height of the liquid level sensor, and to achieve this purpose. The float was configured to move in a direction oblique to the direction perpendicular to the liquid surface.

(Example) The present invention will be explained below based on the drawings.

FIG. 1 shows a sectional view of an embodiment of a liquid level sensor according to the present invention, in which the same components as in FIG. 5 are denoted by the same reference numerals. In this example,
A spherical float 1 is housed in an inclined case 6,
A magnet 2 is provided at the bottom of the float 1. magnet 2
is always below float 1 due to gravity. Reed switches 4a and 4 are located in the case 6 at a position facing the magnet 2.
bffi is provided and fixed by filling with resin 5. The height positions of reed switches 4a and 4b correspond to the H level and L level to be detected, respectively. The case 6 is fixed to a mounting seat 11 provided on the oil pan 10 by welding or the like with a screw 1°6.

When the liquid level is at the H level in Figure 1, the float 1 is near the upper end of the case 6, and the magnet 2 is connected to the reed switch 4a.
Turn on. Also, when the liquid level shifts to L level,
The float 1 moves diagonally to the lower left in FIG. 1 and turns on the reed switch 4b. As a result, H level and L level detection is performed.

In this way, the float 1
moves in a direction that is more inclined than perpendicular to the liquid surface, so
The amount of movement of the float 1 is larger than the amount of displacement of the liquid level, and the amount of displacement is magnified accordingly, so that measurement accuracy can be improved.

Furthermore, since the magnet 2 is provided below the float 1, the vertically elongated reed switch 4a can be provided in the case 6 below the float 1, and the overall height of the liquid level sensor can be reduced. .

FIG. 2 is a sectional view of another embodiment of the liquid level sensor according to the present invention, in which the same components as in FIG. 1 or 5 are designated by the same reference numerals. In this embodiment, the case 6 is curved, and the center line of the case 6 changes such that as the liquid level rises, the angle of inclination with respect to the perpendicular to the liquid level increases. In this way, the liquid level changes.
The measurement accuracy is improved by magnifying and detecting the position amount as the movement m of the float 1.

3 and 4 are cross-sectional views of other embodiments of the liquid level sensor according to the present invention, in which the same components as in FIG. 1 or 5 are denoted by the same reference numerals. be. FIG. 4 is a plan view of FIG. 3.

In this embodiment, the case 6 has a spiral shape, and the float 1 moves while rotating inside the case 6 in response to changes in the liquid level. In this way, the measurement accuracy is further improved by further enlarging and detecting the liquid level displacement I as the amount of rotational movement of the float 1.

(Effects of the Invention) As explained above, the present invention is configured such that the fo-4- moves in a direction oblique to the direction perpendicular to the liquid level, which improves the accuracy of measuring the liquid level and The height of the liquid level sensor can be lowered.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the liquid level sensor according to the present invention, FIG. 2 is a cross-sectional view showing another example of the liquid level sensor according to the present invention, and FIG. 3 is a cross-sectional view showing another example of the liquid level sensor according to the present invention. FIG. 4 is a plan view of FIG. 3, and FIG. 5 is a cross-sectional view of a conventional liquid level sensor.

Claims (1)

[Claims] A liquid level sensor comprising a float that moves according to the liquid level, a magnet attached to the float, and a switch that is opened and closed by the magnetic force of the magnet, wherein the float moves in a direction perpendicular to the liquid level. A liquid level sensor characterized in that it moves in a direction inclined to the surface.