US2228956A - Circuit breaker - Google Patents

Description

Jan. 14, 1941. J. H. HELLAND 2,228,956

CIRCUIT BREAKER Filed June 1, 1938 IN V EN TOR.

BY I

ATTORNEYS.

Patented Jan. 14, 1941 UNITED STATE CIRCUIT BREAKER John H. Helland, Newark, Ohio, assignor of onethird to William M. Pearson, Ncwark,-0hio Application June 1, 1938, Serial No. 211,300

2 Claims.

This invention relates to circuit breakers, and particularly to circuit breakers of the automati cally controlled type, the primary object of the invention being to provide a circuit breaker for use in the usual fuse plug socket, the device being so constructed that an overload current will automatically cause the operation of the de vice to break the circuit in which the circuit breaker is positioned, thereby protecting the line and appliances connected therein.

An important object of the invention is to provide a device of this character which will be sen sitive to abnormal heat caused by an overload current passing through the device.

A further object of the invention is to provide a circuit breaker which will operate instantaneously, and one which must be returned to its operative or reset position by an attendant, thereby preventing the operation of the device until the abnormal condition causing the overload current, has been corrected.

With the foregoing and other objects in view, which will appear as the description proceeds, the

invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein described, may be made within the scope of what is claimed, without departing from the spirit of the invention.

Referring to the drawing:

Figure 1 is a longitudinal sectional view through a circuit breaker constructed in accordance with the invention.

Figure 2 is a transverse sectional view taken on line 22 of Figure 1.

Figure 3 is a transverse sectional view taken on line 3-3 of Figure 1.

Referring to the drawing in detail, the housing or body portion of the circuit breaker is indicated generally by the reference character 5, the lower end of the housing being closed by the disk-like member 6, constructed of suitable insulating material, and held to the housing or body portion 5, by means of the screw shell 1, which is formed with an annular inwardly extended flange 8 that engages the disk-like member, and holds the disk-like member against one end of the housing or body portion.

Supported by the disk-like member 6, is the stationary contact member 9 of the circuit breaker, which is normally in contact with the movable contact member l0 carried at the lower end of the threaded rod I I, the contact member ID being in the form of a cap, threaded on the lower end of the rod l I.

As shown, the threaded rod H' is hollow and supports the expansible disk-like member l2 at its upper end, the member I2 being in communication with the hollow threaded rod and adapted to contain ether or other suitable liquid which will expand under the action of heat.

The member I 2 is connected with the member l3 which embodies a length of flat steel spring material that has its ends held within the groove l4 formed in theliner l5 constructed of iron held within the housing or body portion 5. The length of the member i3, is such that when positioned within the groove H, the member I3 is bowed. When the member i3 is bent downwardly, as shown by Figure 1 of the drawing, the contact member I0 is engaging the stationary contact member 9. It is obvious that when the member l3 moves upwardly, and the member l3 snaps past dead center, the movable contact member ill will be moved away from the member 9, breaking the circuit.

Mounted on the threaded rod l I, is a spoollike piston l6 constructed of iron which provides a support for the resistance coil I! which is wound therearound. One end of the electromagnetic coil i'l connects with the movable contact member ill, at I8, the opposite end of the electromagnetic coil i'l indicated at i9, extends through the insulating member of the piston Hi from where it passes between the lower end of the piston l6 and disk-like member 6, and connects with the copper strip 2| that extends along the housing 5 and connects with the screw shell I. The cover for the housing or body portion 5 is indicated by the reference character 22, and is constructed of suitable insulating material such as Bakelite or the like. This cover 22 is formed with a central opening in which the push button 23 extends, the push button 23 being designed to engage the spring member i3, to return the spring member to its normal active position, after it has been actuated to break the circuit.

Ventilating openings indicated at 24 are formed in the cover 22 and permit of a circulation of air through the housing or body portion.

Due to the construction shown and described, it will be seen that the contact member ID will rest against the stationary contact member 9, completng the circuit to the circuit breaker, under normal conditions. Should an overload occur, it is obvious that the electromagnetic coil I! will become heated, with the result that the ether or liquid contained in the rod it and'expansible disk-like member It, will become heated,

move away from the contest member 9, breaking the circuit through the housing or hody portion 5.

In order to reset the circuit breaker, it is only necessary to press the button 23 downwerdly against the member it, until the member is reeves past dead center end snaps to its active or operative position,

It might be further stated that due to the construction of the rod. iii, the piston, and contact member it may be adjusted with respect thereto to insure a true operation of the circuit breaker.

I claim:

l. A circuit breaker comprising a housing, a threaded shell on the housing and adapted to be positioned in a standard socket, contacting stetionary and movable contact members in the housing, a thermal element within the housing. a hollow rod movable with the thermal element and on which the movable contact member is secured, said rod and thermal element containing ether, a coil within the housing and in ciroverload current, expanding the thermal element and operating the rod whereby the circuit between the contact members is broken.

2. A circuit breaker comprising a. housing, a threaded shell on the housing and adapted to be positioned in a standard socket, a stationary contact member disposed at one end of the housing, a length of fiat spring steel material normally bent past dead center, mounted within the hensing, a thermal element mounted within the housing, and being connected to the length of flat steel material at a. point intermediate the ends thereof, said thermal, element comprising a hoilow rod and an expansible member connected to the rod, a, stationary contact member secured at one end of the casing, a, movable contact member secured to one end of the rod and engaging with the stationary contact member completing a circuit, said thermal clement containing ether, a. coil mounted on sold hollow tube and being in circuit with the shell and movable contact member, said coll adapted to heat the ether in the thermal element under an overload. current, expanding the thermal element, breaking the cir cultbetwecn the contact members, and said length of spring steel material adapted to bend past dead center in the opposite direction, holding the contact members separated.

JOHN H. HELLAND.

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