US2074559A

US2074559A - Temperature responsive switch

Info

Publication number: US2074559A
Application number: US40199A
Authority: US
Inventors: Radtke Bruno
Original assignee: EXHIBIT SUPPLY Co
Current assignee: EXHIBIT SUPPLY Co
Priority date: 1935-09-12
Filing date: 1935-09-12
Publication date: 1937-03-23
Anticipated expiration: 1954-03-23

Description

TEMPERATURE RESPONS IVE SWITCH Filed Sept. 12, 1955 INVENTOR.

[77-5 ATTORNEYS,

Patented Mar. 23, 1937 PATENT OFFICE TEMPERATURE RE SFONSIVE SWITCH Bruno Radtke, Chicago, Ill., assignor to Exhibit Supply Company, Chicago, 111., a corporation of Illinois Application September 12, 1935, Serial No. 40,199

2 Claims.

This invention relates to a temperature-responsivc switch.

It is an object of this invention to provide an improved temperature-responsive switch which is relatively simple and inexpensive in construction and efficient in use.

Among the several objects of the invention is the provision of a novel temperature-responsive or thermostatic switch used in connection with electrical equipment where there is a possibility that the electrical apparatus may, during the course of operation, stick or stop and create a high current flow in the line and a consequent possibility of burning out some of the electrical apparatus, batteries or the like; or where there is a possibility of running the same down; the object of this invention being to provide a novel temperature-responsive switch vwhereby whenever an excessive current fiow is set up in the line, the switch will automatically open and thereby open the circuit in the line, thus protecting the electrical apparatus which may be arranged therein.

Other objects will appear hereinafter.

25 The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing showing 30 the preferred form ofconstruction, and in which:

Fig. 1 is a vertical sectional view showing a preferred form of the present invention;

Fig. 2 is a bottom plan view taken on line 2-4 in Fig. 1, and

Fig. 3 is a schematic wiring diagram illustrating the present invention in one of its typical uses.

In the operation of electrical devices in which there are moving parts-some of these may de- 40 velop a tendencyto bind or stick and thus create a condition in the circuit wherein the current fiow becomes excessive, causing a temperature rise in the conductors or in the mechanism in circuit,

' and thereby cause a drain on the source of 45 energy, and there also is a possibility that some of the equipment may also become over-heated and be ruined.

To prevent the difilculties enumerated above,

I have provided a temperature responsive switch 50 which is generally indicated at ID. This switch Ill has a central metal strip II, and formed integrally with the strip H is a metal contact I2 which is threaded, as at H, so that it may be.

adjusted relative to a movable contact H, the 55 contact l2--I3 having a slot l5 formedin one end thereof so as to facilitate the adjustment of the contact I2 relative to the movable contact l4. Also threaded upon the body I3 is a'locking device in the form of a nut IS.

The movable contact I! is mounted upon a bi-metallic strip of metal I'l, this bi-metallic strip I] being composed of two thin strips l8 and IQ of metal of different compositions held together in close relationship so as to form a. unitary member. This strip [1 is mounted upon a base by means of a rivet or the like 2|.

Separating the metal strip H from the base 20 is an insulating member 22 which may be composed of fibrous material, hard rubber, or the like, and this member 22 has a small raised portion 23 which is fitted into the opening 24 of the strip II. The members II and 20 are fastened together by means of screws or the like 25, the head 26 of the screw being insulated from the member I l by another strip 21 of fibrous material, hard rubber, or the like 2|, 'and this strip 2'! is also provided with raised portions 28 which are fitted into the opening 24.

An electrical conductor 29 is fastened to the metal strip II by means of a metal screw or they like 30, current thus passing from the conductor 29 through the screw 30 into the strip II and through its contact point l2, through the movable contact point l4, the bi-metallic strip [1, the base20, the screw 25, and back through the conductor 3|, the present switch being thus connected in series in the circuit 32 (Fig. 3) which shows diagrammatically how the switch I0 may be connected in series in a typical circuit 32,

' which may include a motor or some other electrical mechanism 33, and also a source of energy in the form of a battery .or the like 35; it being understood that the present switch I0 may be used in conjunction with any type of electrical apparatus.

It has been found that frequently 'when an electrical mechanism is in operation, the same will inadvertently stop and cause a dangerous rise in current in the circuit, and when such a contingency arises, the source of current 35 may be drained or the motor or other apparatus which may be embodied in the circuit may be burned out.

When such a contingency arises in the use of -the present protective switch, the excessively heavy current passing through the circuit 32 causes the bi-metallic strip I! to become heated the latter being dimensioned for predetermined loads or currents, and due to the difference in the expansionco-eflicients of the metals l8 and l9, the bi-metallic strip I1 is caused to expand (from full line to dotted line position, Fig. 1), thus separating the contact points l2 and M, and thereby opening the circuit 32. The circuit 5 32 being thus opened removes the load from the line. When the bi-metallic strip ll cools there being no current flow to heat it, the circuit 32 is again closed at that point since the strip l1 will return to its normal closed circuit condition, whereupon the operation of the mechanism may be resumed.

, While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to.be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A thermostatic switch for use with game apparatus and comprising a substantially elongated arm having a pair of oppositely directed orificed side wings extended from its sidesintermediate its longitudinal extremities, said wings being bowed adjacent the juncture with said elon- 3 gated arm to raise the latter above the plane of the wings, an elongated bi-metallic contactor extended from and secured to one of the longitudinal extremities of said arm, a second elongated.

contact arm insulated from and secured to said first arm, said second arm having an angled end portion overlying said bi-metallic member, an

adjustable contact member threaded through said angled end portion adjacent the outermost extremity thereof and threadable toward and away from said bi-metallic member, together with means including a member threadable onto said adjustable contact member and against said lastmentioned arm to lock said adjustable contactor in position.

2. Athermostatic switch for use with game apparatus and comprising a substantially elongated arm having a pair of oppositely directed orificed side wings extended from its sides intermediate its longitudinal extremities, said wings being bowed adjacent the juncture with said elongated arm to raise the latter above the plane of the wings, an elongated bi-metallic contactor extended from and secured to one of the longitudinal extremities of said arm, said extremity being tapered in a direction toward its juncture with said bi-metallic contactor, a second elongated contact arm insulated from and secured to said first arm, said second arm having an angled end portlon overlying said bi-metillic member, an adjustable contact member threaded through said angled end portion adjacent the outermost extremity thereof and threadable toward and away from said bi-metallic member, together with means including a member threadable onto said adjustable contact member 'and against said lastmentioned arm to lock said adjustable contactor in position, and said second contact arm having an elongated tapered tail portion at its extremity opposite said angled end portion and extended beyond the underlying extremity of said firstmentioned contact arm.

' BRUNO RADTKE.