GB2062964A

GB2062964A - Float operated switch

Info

Publication number: GB2062964A
Application number: GB7920488A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-06-12
Filing date: 1979-06-12
Publication date: 1981-05-28

Abstract

A float operated electric switch comprises a fluid casing A for containing a fluid G and a switch casing H positioned above the fluid casing and inside which, the fixed contacts E1, E2 of the switch are mounted, a sleeve L housing a spindle C and connecting the switch and the fluid casing, a movable contact D mounted at one end of the spindle projecting inside the switch casing H and a float B connected to the other end of the spindle C, the arrangement being such that the float B descends due to the decrease in level of the fluid thereby to move the spindle C down to establish contact between the fixed contacts E1, E2 and the movable contact D. <IMAGE>

Description

SPECIFICATION Float operated switch An object of this invention is to propose a float operated switch which can make or break an electrical circuit on sensing the change in level of a liquid substance in a container.

Although float switches are known and in use, the novelty of this invention, which functions as a float switch is in its nonvel construction by which the cost of manufacture is reduced by using reseinous material such as high density polytheiene and/or polypropolene and the swtich can also be mounted in limited space, such as available in brake fluid reservoirs of motor vehicles and the switch can be used for indicating the depletion of brake fluid by audio/visual means to the driver and thus prevent brake failure due to depletion of brake fluid. The switch also finds application in boilerfeed water systems, in overhead storage tanks, in chemical process industries, in oil refineries, in motor tankers, oil tanker ships and chemical carrier ships.

According to this invention there is provided a float operated electric switch comprising of a fluid casing for containing a fluid and a switch casing positioned above the fluid casing and inside which, the fixed contacts of the switch are mounted, a sleeve housing a spindle and connecting the switch and the fluid casing, a movable contact mounted at one end of the spindle projecting inside the switch casing and a float connected to the other end of the spindle, the arrangement being such, that the float descends due to decrease in level of the fluid, thereby to move the spindle down to establish contact between the fixed contacts and the movable contact to operate an electrically operable actuating mechanism.

The float operated switch proposed herein will now be described with reference to the accompanying drawing in which Figure 1 represents the switch for use in hydraulic braking systems of vehicles.

Referring to Figure 1 A is a container within which is disposed a float B, and C is a spindle to one end of which is attached a circularly shaped movable contact member D. Two other fixed contact members isolated from each other and indicated as E1 and E2 are connected to an electrical circuit F.

H is a casing for segregating the contact members D, E1 and E2 from container A. Tare the two electric terminals, Ware lock washers. L is a sleeve housing the spindle C and connecting the switch casing to the container A. The container A receives the brake fluid G of the braking system of the vehicle and whenever possible or convenient, the brake fluid reservoir with which the braking system itself is equipped will be constituted into the container A, in other cases the brake fluid system will be connected suitable to the container A so that there is free movement of the fluid between the brake fluid system and the contain er A.

Assuming now that the brake fluid G in the container A falls to, or below, a predetermined unsafe level, the float, B descends with the level of the brake fluid G to cause the contact member D and the contact members E1 and E2 to establish contact and complete the electric circuit F.

The electric circuit F, when completed is such that it energises perceptable means of indication or warning, such as for instance, a warning lamp or a buzzer installed on the dashboard panel of the vehicle to caution the Driver about the depletion of brake fluid G to a predetermined unsafe level and possibility of brake failure.

Alternatively or additionally the electric circuit F when completed is such that it actuates a mechanism intended for the safety braking of the vehicle.

Alternatively or additionally the electric circuit F when completed is such that it actuates a mechanism intended for shutting off the engine.

It would be clear from the foregoing description relating to a specific application concerning vehicle braking systems working on Hydraulic braking system that the switch proposed herein can find other applications wherein a sensing device is required to actuate electrically operable mechanisms on sensing the change in level of a liquid substance.

The terms and expressions used in these specification are of description and not of limitation, since the switch proposed herein is not confined to its embodiments described and illustrated, but various other embodiments thereof are possible without departing from the scope and ambit of this invention.

1. A float operated electric switch comprising of a fluid casing for containing a fluid and a switch casing positioned above the fluid casing and inside which, the fixed contacts of the switch are mounted, a sleeve housing a spindle and connecting the switch and the fluid casing, a movable contact mounted at one end of the spindle projecting inside the switch casing and a float connected to the other end of the spindle, the arrangement being such that the float descends due to decrease in level of the fluid, thereby to move the spindle down to establish contact between the fixed contacts and the movable contact to operate an electrically operable actuating mechanism.

2. Afloat operated switch as claimed in claim 1 wherein the movable contact is circularly shaped to establish contact with the fixed contacts in any position when the float descends vertically.

3. Afloat operated switch substantially as herein described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Float operated switch An object of this invention is to propose a float operated switch which can make or break an electrical circuit on sensing the change in level of a liquid substance in a container. Although float switches are known and in use, the novelty of this invention, which functions as a float switch is in its nonvel construction by which the cost of manufacture is reduced by using reseinous material such as high density polytheiene and/or polypropolene and the swtich can also be mounted in limited space, such as available in brake fluid reservoirs of motor vehicles and the switch can be used for indicating the depletion of brake fluid by audio/visual means to the driver and thus prevent brake failure due to depletion of brake fluid. The switch also finds application in boilerfeed water systems, in overhead storage tanks, in chemical process industries, in oil refineries, in motor tankers, oil tanker ships and chemical carrier ships. According to this invention there is provided a float operated electric switch comprising of a fluid casing for containing a fluid and a switch casing positioned above the fluid casing and inside which, the fixed contacts of the switch are mounted, a sleeve housing a spindle and connecting the switch and the fluid casing, a movable contact mounted at one end of the spindle projecting inside the switch casing and a float connected to the other end of the spindle, the arrangement being such, that the float descends due to decrease in level of the fluid, thereby to move the spindle down to establish contact between the fixed contacts and the movable contact to operate an electrically operable actuating mechanism. The float operated switch proposed herein will now be described with reference to the accompanying drawing in which Figure 1 represents the switch for use in hydraulic braking systems of vehicles. Referring to Figure 1 A is a container within which is disposed a float B, and C is a spindle to one end of which is attached a circularly shaped movable contact member D. Two other fixed contact members isolated from each other and indicated as E1 and E2 are connected to an electrical circuit F. H is a casing for segregating the contact members D, E1 and E2 from container A. Tare the two electric terminals, Ware lock washers. L is a sleeve housing the spindle C and connecting the switch casing to the container A. The container A receives the brake fluid G of the braking system of the vehicle and whenever possible or convenient, the brake fluid reservoir with which the braking system itself is equipped will be constituted into the container A, in other cases the brake fluid system will be connected suitable to the container A so that there is free movement of the fluid between the brake fluid system and the contain er A. Assuming now that the brake fluid G in the container A falls to, or below, a predetermined unsafe level, the float, B descends with the level of the brake fluid G to cause the contact member D and the contact members E1 and E2 to establish contact and complete the electric circuit F. The electric circuit F, when completed is such that it energises perceptable means of indication or warning, such as for instance, a warning lamp or a buzzer installed on the dashboard panel of the vehicle to caution the Driver about the depletion of brake fluid G to a predetermined unsafe level and possibility of brake failure. Alternatively or additionally the electric circuit F when completed is such that it actuates a mechanism intended for the safety braking of the vehicle. Alternatively or additionally the electric circuit F when completed is such that it actuates a mechanism intended for shutting off the engine. It would be clear from the foregoing description relating to a specific application concerning vehicle braking systems working on Hydraulic braking system that the switch proposed herein can find other applications wherein a sensing device is required to actuate electrically operable mechanisms on sensing the change in level of a liquid substance. The terms and expressions used in these specification are of description and not of limitation, since the switch proposed herein is not confined to its embodiments described and illustrated, but various other embodiments thereof are possible without departing from the scope and ambit of this invention. CLAIMS