JPS595848B2 - A device that indicates the level of liquid in a container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a device for indicating a predetermined liquid level in a container, particularly the lowest oil level in a crankcase of an automobile,
a float having a magnet and a magnetically operable electrical switch located within an indicating electrical circuit, the float and electrical switch being disposed within a tubular casing, the interior of the casing being relates to a type in which it is connected to an external chamber via at least one opening.

In order to indicate the minimum oil level in the crankcase of a motor vehicle, a float having a permanent magnet inside a tubular casing and sliding along a guide tube and a magnetic magnet installed in the lower region of the guide tube are used. Devices are known which are equipped with an operable switch. The tubular casing is closed at one end by an electrical connection and at the other end by a bottom, which is provided with an oil flow opening connecting the interior of the casing with the outside. The cross section and length of the oil flow openings are dimensioned in such a way that a certain throttling effect occurs, so that fluctuations in the height of the oil level outside the casing are transmitted to the interior of the casing with a time delay. It's getting old. In this way, short-term fluctuations in the oil level in the crankcase, in particular within the range of the minimum oil level, such as occur, for example, when a motor vehicle passes a curve at high speed or during acceleration and braking. Fluctuations in are prevented from being indicated. However, if the lubricating oil has not been heated to normal operating temperatures, especially in the case of short-distance driving, the reduction of the oil level from a predetermined minimum value may not be indicated or may be indicated very late. There was found.

This is because the oil has a high viscosity, so that the oil only slowly flows out of the casing interior after the engine is started. Moreover, as time passes, iron powder adheres to the oil flow opening, increasing its squeezing effect. The object of the invention is therefore to eliminate these drawbacks and to ensure that a device of the type mentioned at the outset reacts reliably when the liquid level reaches a predetermined value.

To this end, the invention provides at least one additional opening of large cross section connecting the housing interior to the outside, which additional opening is provided with a bimetallic snap element. It was made so that it could be closed.

The advantage obtained with this embodiment of the invention is that even when the oil is cold and viscous, there is a large through-flow cross-section hole - the bimetallic snap element is in a position to open an additional opening, so that oil and dust can be removed. On the other hand, when the oil is heated to operating temperature, only the normally provided through-flow cross section acts - the bimetallic snap element closes the additional opening. occupy a position.

The device according to the invention therefore responds reliably regardless of the temperature of the oil and thus the viscosity of the oil. Furthermore, in an embodiment of the invention a magnet is arranged on the outside of the housing in the area of the opening.

This prevents iron powder present in the oil from accumulating in the opening and gradually blocking it. In an embodiment which is advantageous for manufacturing and mounting technology reasons, the additional opening is formed in the housing bottom concentrically with respect to the housing axis, and a bimetallic snap element in the form of a curved disk is provided in the housing. located within a chamber-like addition of. An additional advantage of this embodiment is that the housing shell has no additional parts, so that the housing can be easily inserted into the opening provided for the housing in the crankcase. be. Furthermore, it is advantageous if the magnet is provided as the bottom of the chamber-shaped extension. The configuration of the present invention will be specifically explained below with reference to the drawings.

The signal generator of the device consists of a tubular metal casing 1, which is closed at one end with a plug 2, which has a thread 3, a hexagonal head 4 and an electrical connection 5. have.

The other end of the casing 1 transitions into the bottom 6. Concentrically arranged in the housing 1 is a guide tube 7 for a float 8, which float 8 has a permanent magnet 9. A magnetically operable switch 10, for example a reed switch, is mounted in the lower region of the guide tube 7.
When the permanent magnet 9 of the float 8 is located above the switch 10, the switch 10 is open and no current flows through the alarm circuit. However, when the float 8 reaches the position shown, the switch 10 is actuated by the permanent magnet 9 and current flows through the switch 10, the electrical connection 5 and a lamp (not shown) in the alarm electrical circuit. lights up to notify the driver that the minimum oil level has been reached. As can be seen in particular from FIG. 2, an opening 11 is formed in the bottom 6, through which the oil flows into the inner chamber 13 of the casing 1.
can be reached.

In this case, the channel 12 is formed by the groove in the holding element 14 for the guide tube 7 and the bottom 6 of the housing 1.
Furthermore, the bottom part 6 and the retaining element 14 are penetrated by openings 15 and 16 concentric to the longitudinal axis of the housing, the opening 15 being connected via a wide slot 17 to the interior of the housing. The opening 16 cooperates with a bimetallic snap disk 18, which is supported by a disk 19 of diamagnetic or paramagnetic material.
A permanent magnetic disk 20 is provided below the disk 19. Theoretically, the bimetallic snap disc 18 could be supported directly on the disc 20;
Therefore, there is a risk that the magnetic force acting on the bimetallic snap disc 18 will adversely affect the opening/closing function of the bimetallic snap disc 18. When the oil is heated to operating temperature, the bimetallic snap disc 18 is in the position A shown, the opening 16 is closed and the oil flows through the opening 11 and the passage 12.
only through the casing interior with a certain delay into or from the casing interior. On the other hand, when the oil is cold, the bimetallic snap disk 18 occupies position B and is curved in the opposite direction. In this state, the opening 16 is open and the oil can flow through the wide slot 21 of the extension 22 and the large cross-sectional openings 15 and 16 into or out of the housing interior almost without delay.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view of one embodiment of the invention, and FIG. 2 is an enlarged vertical sectional view of the lower portion of the device shown in FIG. 1...Casing - 2...Blug,
3...screw thread, 4...hexagonal head, 5...
...Electrical connection member, 6...Bottom, 7...
... Guide tube, 8 ... Float, 9 ...
・Permanent magnet, 10... Switch, 11...
... Opening, 12 ... Passage, 13 ... Inner chamber, 14 ... Holding member, 15, 16 ...
・Opening, 17...Slit, 18...
Bimetal snap disc, 19...Disc, 20
...Disk, 21...Slit, 22.
...Additional part, A-B...Position.

Claims (1)

[Claims] 1. A device for indicating a predetermined liquid level height in a container,
a float having a magnet and a magnetically operable electrical switch located within an indicating electrical circuit, the float and electrical switch being disposed within a tubular casing, the interior of the casing being is connected to the outer chamber via at least one opening, in which case at least one additional opening 15, 16 of large cross section is provided which connects the inner chamber 13 of the casing to the outside; Device for indicating the liquid level in the container, characterized in that this additional opening can be closed by a bimetallic snap element. 2. The device according to claim 1, wherein a magnet is arranged on the outside of the casing 1 in each case in the area of the openings 15, 16. 3. an additional opening 16 is formed in the bottom 6 of the casing concentrically with respect to the casing axis, and a disc-shaped bimetallic snap member is arranged in the chamber-shaped addition 22 of the casing 1; An apparatus according to claim 1. 4. Device according to claim 3, characterized in that a magnet arranged outside the housing 1 in the area of the openings 15, 16 is provided as the bottom of the chamber-shaped extension 22. 5. A disk 19 made of diamagnetic or paramagnetic material is disposed between the magnet and the bimetallic snap member.
An apparatus according to claim 4.