US1840691A - Switch - Google Patents

Description

Jan. 12, 1932. M, B BLOOM E1- A| 1,840,691

SWITCH Filed June 18, 1930.

VIII

@hoi/nuja Patented Jan. 12, 1932 UNITED sTATEs PATENT OFFICE f MORRIS B. BLOOM AND JOSETH L. BERNSTEIN, F HARTFORD, CONNECTICUT, ASSIGNORS OF ONE-THIRD T0 HARRY BLOOM, OF HARTFORD, CONNECTICUT SWITCH Application led June 18,

The invention relates to an improved device for completing an alarm circuit when a liquid in a tank reaches a predetermined level, the principal use of the invention being to indicate when the fuel in the supply tank of a liquid fuel burner (domestic or industrial), is low and requires replenishing, the construction being such that it may be effectively used w whether the tank bel below or above the ground or floor level.

When the switch is installed, it is controlled by a float in the tank, float and switch being connected by a chain or other flexible member passing through a pipe. This pipe supports the switch-containing casing and necessarily,

communicates with this casing and the tank, and it is one important aim of the invention to provide a novel constructionpreventing gas or fumes from the tank, from escaping to the building or furnace room by way of said pipe and casing, at the same time providing for enclosing all switch parts and electrical connections for safety and protective purposes.

A further aim of the invention is to provide a structure of extremely simple and inexpensive nature, one which cannot easily getout of order and one which will be long-lived and continuously eliicient.

With the foregoing in view, the invention resides in the novel subject matter hereinafter described and claimed, description being accomplished by reference to the accompanying drawings. l

Fig. 1 is a vertical sectional view partly in elevation showing the invention operativelyconnected with a tank, aremovable side wall of the switch containing casing, being detached in this view.

Fig. 2 is a horizontal sectional view on line 2-2 of Fig. 1. n Fig. 3 is a vertical sectional view on line 3-3 of Fig. 1.

Fig. 4 is a perspective view of the switch lever and associated elements.

The numeral 5 on the drawings denotes a liquid-containing tank with which a pipe 6 is rigidly connected, said pipe extending up- A wardly from said tank and being threaded 1930. serial No. `4.611,091.

into a neck 7 on the bottom 8 of a casing 9, which casing contains a switch and electrlcal connections therefor. A float 10 is provided in the tank 5 for closingthe switch when the liquid in said tank lowers to a predetermined level, said iioat being connected with the lower end of a chain 11 which passes through the pipe 6, the upper end of the chain being connected with the switch as hereinafterV described. This chain is preferably of the con-A ventional bead-like form, commonly used for pull chains on electrical xtures, and by providing a chain of this type, there is no liability of it becoming tangled or caught upon any parts.

The casing 9 is preferably of two-part construction and formed from alvanized, castiron or the like. One part o this casing constitutes the majority of the' latter and embodies the bottom 8, the top 12, two vertical side walls 13 and 14, a back wall 15, and a horizontal partition 16. The casing portions 8, 12, 13, 14 and 16 are of uniform width and are all integrally joined to each other. The other part of the two-part casing is constituted by a removable front side wall'17 which is secured in place by screws or the like 18, a packing sheet 19 being clamped between said wall 17 and the front edges of the casing parts 8, 12, 13, 14 and 16. The partition 16 divides the casing 9 into a lower switch chamber S and an upper conductorconnecting chamber C, chamber S being provided with the neck 7 and chamber 15 being provided with a similar neck 19 for connecting a conductor conduit 20 thereto. This conduit may of course be either a pipe or the conventional flexible armor. The conductors passing through the pipe are denoted at 21. Two openingIsJ 22 are formed through the partition 16. assing through these openings are two binding posts 23 provided not only with means 24 insulating them from the partition 16, but with packing means 25 preventing any gases or fumes from ascending to the chamber C from the chamber S, so that these fumes cannot travel on through the conduit 20 and escape into any portion of the building in which the invention `is used. The upper ends of the binding posts 23 are provided with nuts 26 in the chamber- C for the purpose of clamping the conductors 2l to said binding posts. T he lower ends of these binding posts are provided with nuts 27 in the chamber S, said nuts connecting said posts with two ilexible conductors 2S. These conductors 2S are provided with electrodes 29 in a tube 30 containing a quantity oi' mercury Si, and when said electrodes are bridged by the mercury, the circuit for the alarm is completed.

A lever 32 is provided to carry the tube 30. This lever is fulcrumed between its ends at 33 and is provided with a spring clip 34 which holds the tube 30. One end of lever 32 is disposed over the neck 7 and is connected with the upper end of the chain l1. The other end of lever 32 is provided with a weight 35 held in place by a screw or the like 36. This weightnormally overbalances the weight of the chain ll. and holds the lever 32 in the position shown in F ig. l, said weight then resting upon the bottom 8. In this position of the lever, the mercury 3l is at the end ot' the tube 8() remote from the electrodes 29, and the chain ll is slack within the tank 5, until the liquid level lowers beyond a predetermined extent. Vhen such lowering takes place, however, the float 10 descends, pulls upon the chain ll and overcomes the action of the weight 35, the result being that the lever .32 is tilted to cause the mercury 3l to descend by gravity against the electrodes 29. Thus, upon lowering of the liquid level beyond a predetermined extent, the alarm circuit is completed.

It will be seen from the foregoing that the invention is simple and inexpensive, may be readily manufactured and sold at small cost, will be ellicient and long-lived, will afford eliective protection for all electrical connections and switch parts, and will prevent escape ot any gases or fumes. On account ol these advantages, the details disclosed are preferably followed. However, within the scope of the invention as claimed, variations may of course be made.

We claim:

In a gas seal and level indicator switch for a fuel tank, a casing above said fuel tank comprising a vertical back wall, top and bottom walls, vertical side walls and a horizontal partition wall; said top, bottom, side and partition walls being of uniform width and being unitarily and gas-tightly connected with said back wall; said side walls being unitarily and gas-tightly connected also with said top, bottom and partition walls; and a one-piece removably secured front wall ly ing gas-tightly against the free edges of said top, bottom, Side and partition walls, removal of said front wall serving to give access to the interior of the casing both above and below said partition wall; said bottom having a pipe-connecting opening and one of said walls having a conductor entrance opening above said partition wall, a vertical pipe connected gas-tightly with and rising from the fuel tank, the upper end of said pipe being gas-tightly secured in said pipe-c011- necting opening, binding posts passing gastightly through and insulated from said partition wall, the upper ends of said binding posts being accessible for conductor connection when said front wall is removed, a switch mounted in said casing below said partition wall and conductively connected with said binding posts, a switch-operating member loosely received in said pipe and connected at its upper end with said switch, and a float in the fuel tank connected with the lower end of said switch-operating member.

In testimony whereof we affix our signa-

Images