US840614A

US840614A - Electric-circuit breaker.

Info

Publication number: US840614A
Application number: US23859604A
Authority: US
Inventors: Stanley B Freiberg
Original assignee: Individual
Current assignee: Individual
Priority date: 1904-12-28
Filing date: 1904-12-28
Publication date: 1907-01-08
Anticipated expiration: 1924-01-08

Description

' No. 840,614. PATENTED JAN. 8, 1907;

s. B. PREIBERG. ELECTRIC CIRCUIT BREAKER.

' APPLICATION FlLED DBO. 2 1904. v

2 SHEETS-SHEBT 1.

No. 840,614. PATENTED JAN. 8, 1907.

S. B. PRBIBERG. ELECTRIC CIRCUIT BREAKER.

APPLICATION FILED DEC. 28, 1904.

2 SHEETS-SHEET 2.

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Specification of Letters Patent.

Patented Jan. 8, 1907.

Application filed December 28. 1904;. Serial No. 238,596.

To (tZZ whom it may concern:

Be it known that I, STANLEY B. FREIBERG, a citizen of the United States, residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Electric -,Circuit Breakers, of which the following is a specification.

My invention relates to circuit-breakers, and has for its object the providing of a circuit-breaker especially adapted for light work and is intended to take the place of fuses in house-wiring and the invention consists in providing the circuit, preferably the positive and negative conductors or wires thereof heretofore provided with fuses, with a pair of circuit-breakers so arranged that upon the occurrence of abnormal current in the circuit one or the other or both of the circuit-breakers will automatically disconnect for breaking the circuit, the circuitbreakers being so arranged, as hereinafter described, that upon the occurrence of abnormal current the same will open for disconnecting the circuit to which they may be connected, and thus prevent serious accident and fire.

My invention consists, further, in providing a circuit-breaker having metallic releasable contacts and also non-metallic releasable contacts, one of said non-metallic contacts secured directly to the releasing-blade and so constructed and arranged that upon occurrence of abnormal current or overload the non-metallic contacts will remain in contact until after the disengagement of the metallic contacts of the circuit-breaker for preventing burning or welding of the metallic contacts, and, further, in providing a combined manual and automatic circuit-breaker operated directly from an armature.

My invention will be further understood from the following description. and claims and from the drawings, in which- Figure 1 is a diagram view llustrating a circuit in which my improved circuit-breakers are located. Fig. 2 is a front elevatlon of my improved circuit-breakers Fig. 3 is a side elevation of the same, partly broken away. Fig. 4 is a detail in side elevation, showing the relation of the contacts in full lines when the blade is in fully-raised position and in dotted lines when the blade is only partially raised for disengaging the metallic contacts while the non-metallic contacts are still engaged. Fig. 5 is a detail in cross-section on theline a: 00 of Fig. 3, showing thenon-metallic contacts and manner of mounting the same. Fig. 6 is a detail in cross-section on the line i y y of Fig. 3, showing the manner of pivoting I the blade and coiling the spring therefor. Fig. 7 is a detail in perspective, showing the armature and spring for retracting the same. Fig. 8 is a perspective detail of the armaturespring; and Fig. 9 is a detail in section on the line 2 of Fig. 2', showing the manner of mounting the electromagnet.

A represents the translator, shown as an incandescent lamp, of which there may be any suitable number on the circuit, or the translator may consist of a motor or other suitable electrical device.

B is the positive conductor, and O is the In wiring the positive and negative conductors are in practice usually run side by side, although itis obvious that the same may be arranged in other suitable manner. In the conductors of a given circuit I place a pair of my improved circuit-breakers, as shown at E E, in the respective positive and negative conductors of the branch circuit, preferably side by side, although it is obvious that the circuit-breakers of a pairmay be connected in series in either the positiveor negative conductors.

The circuit-breakers of a pair are similarly constructed, and a particular description of one of the pair will suffice for cl'earness, similar parts of the other being referred to by similar reference-numerals bearing the eXponent prime, C.)

In the circuit breaker there is an electromagn'et 1, having a coil 2 and an armature 3, or a solenoid may be substituted therefor. The winding of the electromagnet connects at one end 2 with the binding-post 4, to which one terminal of the conductor of the circuit is secured. The electromagnet is secured to a bracket 5, secured to the baseplate 6 of the circuitbreaker, both circuit breakers of the pair being preferably mounted on this base-plate, which may be slate or suitable non-conducting material. The bracket 5 is U-shaped, having its base take into and guided by the walls of a groove 7 in the base-plate, the bracket being secured in place by a screw 8, which takes through a narrow slot 9 in the base-plate, thereby permitting adjustment of the coil and of the electromagnet toward and from the armature for regulating the capacity of the negative conductor, of the branch circuit D.

breaker, thus permitting the circuitbreaker to be adjusted and set to break at a certain current strength:

The armature is pivoted upon pivots 10 10 to a U-plate 11, secured to the base by a screw 12. The armature is normally retracted from the coil of the electromagnet by a spring 13. This spring is bent reversely upon itself, forming a median loop 14, taking about the screw 12, and each shank of the spring is bent to form a spiral or loop 16 intermediate of its length, the outer ends of the spring being preferably connected as shown at 18 and taking under thearmature, forming a cheap, effective, and delicate spring mechanism for retracting the armature. For limiting the retracting movement of the armature the U-plate 11 has a lug 19. The upper surface of the armature is provided with a lip 20, adapted to receive the blade 21. This lip is slightly above the pivotal point of the armature and has its contacting face slightly inclined rearwardly, the catch 23 of the blade having its contacting face correspondingly inclined forwardly in subst antially the are of swing of the armature for affording a delicate trip for the armature. The blade is released directly from the armature, insuring quick action and simple construction.

The blade 21 is pivoted on a rod 24, taking through an aperture in the end of the blade and through apertures in the sides of a U- shaped bracket 25, secured to the base by a screw 26, a conductor 27 connecting the screw 26 with the. bindingpost 28, to which the other terminal of the conductor of the circuit is secured. A dished washer 29 takes about the rod to each side of the bracket 25, nuts 30, shown as elongated round nuts, taking against the washers for securing the rod in place and delicately regulating the e'ectrical connection of the blade, the blade being thereby resiliently pressed between the sides of the bracket.

A metallic contact for the blade, shown as a U-clip, is secured to the base by a screw 36. A non-metallic contact 37 is secured di rectly on and moves with the blade, and a non-metallic contact 38 is secured to the base. These latter contacts are non-metal lie or non-welding and are preferably carbon. They are preferably pressed toward each other with spring-pressure. Thus the contact 38 is preferably mounted on a spring 39, secured to the base by a nut and screw 40. This spring is preferably a leaf-spring having a bulge 41 therein, giving it long life. The contact-faces 42 43 of the contacts 37 38 are preferably relatively inclined, the springpressure urging contact of those faces throughout the various positions which those contacts assume while side by side and permitting sharp breaking of contact when the blade 21 is retracted sufficiently to bring the contact 37 out of reach of the contact 38. The extreme ends of the contacts 37 38 are abruptly inclined or rounded, as shown at 44 45, so as to permit ready engagement and prevent binding of those contacts when the blade is reset. The other end 2 of the winding of the electromagnet connects with the screws 36 40, so that the metallic and nonmetallic contacts on the base connect with the same terminal of the conductor.

Referring to Fig. 4, it will be noted that when the blade is released for breaking contact the metallic contact is first released while the non-metallic contacts are still in contact, thereby avoiding arcing at the metallic contact, the electricity flowing through the non-metallic contacts for an instant after the metallic contact is released, one of the non-metallic contacts being carried directly by the knife to insure positive action, preventing burning or welding of those metallic contacts, and consequent injury to the same, and insuring safety and certainty in the op eration of the device. Normally the circuit is formed through both the metallic and carbon contacts; but upon breaking of the circuit the metallic contacts are first released. The blade 21 is retracted by a spring 51. This spring is bent at its central portion for forming inwardly-projecting stirrup 52, taking about the blade below the carbon contact 37 and forming shanks 53, taking beyond the pivotal point of the blade, the tail ends thereof being secured by screws 54 to the base. The shanks cross each other above the blade, as shown at 55, thereby acting as a stop for preventing the outward movement of the blade beyond the spring. The inner part of the stirrup takes across the inner edge of the blade and the crossing parts of the shanks take across the outer edge of the blade, thereby forming a loop within which the blade is confined, so as to prevent the blade from accidentally swinging back too far, owing to its momentum, when the blade is released from the armature. Each shank 53 is formed with a helix, loop, or coil 56, taking about one of the nuts 30 of the rod 24, forming a strong spring, providing quick break of circuit. Between the stirrup 52 and loop 56 each shank has an outward bulge for removing the spring from contact with the carbon 37. In order to prevent wear of the contacting face 23 of the blade, the blade being usually of soft metal, such as copper, I provide a reinforce face-piece 57 of harder metal, preferably taking about and riveted to the sides of the blade. The blade is provided with a push-button 58. The armature has an extension 59, on which there is an insulated push-button 60 for permitting the armature to be withdrawn from the blade by hand, making a simple combined manually-operated and automatic circuit-breaker.

IIO

My invention takes the place of fuses, which are expensive in maintenance and also dangerous, and also of the ordinary switch, combining the functions of both in one device. My improved circuitbreaker is not intended for switchboard use, but rather in branch lines carrying limited current. It has few parts and is of cheap and durable construction and capable of accurate adjustment for current strength, making it especially useful for current-circuits for low-current strength. It can be cheaply made, so as to be capable of being used in place of fuses, and is more accurate and delicate and safer than fuse construction, because each circuit-breaker can be definitely tested and adjusted for a given current strength, which is not the case with fuses, the testing of which would destroy the fuse.

During normal current circuit is formed through the circuit-breakers. Upon abnormal current, due to a ground, short circuit, overload, or other cause, the armature of one or both circuit-breakers in the circuit is attracted, thus breaking the circuit, the metallic contacts being first released, for the reason stated. Upon discovery and remedy of the supposed difficulty with the circuit one of the circuit-breakers is first connected. If connection in both has been broken, the blade of the mating circuit-breaker is then pushed into contact for closing this mating circuit-breaker. If the difiiculty with the circuit has been actually found and remedied, both circuit-breakers will now remain closed; but if there should still be abnormal current, ground, or overload in the circuit the firstnamed circuit-breaker will instantly fly open, thus preventing injury to any part of the circuit. There being at least one of the circuit-breakers from which manual resistance to opening or breaking has been removed when the circuit is finally closed and the circuit-breakers breaking independently, injury and danger are removed, because the circuit cannot remain closed while there is abnormal current in it.

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

1. In an electric-circuit breaker, the corrbination with an electromagnet having an armature, a support for said arn'iature, and a base, of a spring for nori'nally retracting said arniature, said spring having a central loop below said armature-support and for ring a pair of strands, a screw 12 taking through said armature-support and loop and into said base for securing said support and spring to said base, each of said strands having a spiral intermediate of its ends, the ends of each of said strands projecting upwardly from one side of said spiral toward said armature-support and armature respectively, and said strands having their outer ends take against said armature for normally retracting the sad; e, a pivoted blade with contacts therefor,

lIBLIlS normally connecting said blade and arniature, and nteans normally acting to separate said blade and armature, substantially as described.

2. In an electric-circuit breaker, the combination of a base, a blade, said blade having a pivot, a spring for said blade, said spring having a central stirrup in which the blade rests at one edge of said blade and forming a pair of strands, said strands being bent across the other edge of said blade and thereby forming a loop about said blade at said stirrup for forming a stop against undue retraction of said blade, said strands extending from said loop toward the pivot of said blade and being coiled substantially coincident with the aXis of said pivot, and nleans for securing the ends of said strands rigidly in position, substantially as described.

3. In an electric-circuit breaker, the combination of a base, a blade, said blade having a pivot, a nietallic contact and a non-metallic contact spaced apart and secured to said base, a nietallic contact and a non-metallic contact spaced apart and secured to said blade, a spring for the blade, said spring having a central stirrup located between said metallic and non-rtetallic contacts on said blade, the inner edge of said blade taking against said stirrup, said spring thereby forming a pair of strands, said strands crossing the outer edge of said blade between said nietallic contact and said non-oi etallic contact thereon and thereby forming a loop within which said blade is confined, said strands spreading from said crossed position outwardly for forming bulges 50 and thereby clearing the non-1r etallic contact on said blade, said strands extending from said bulges toward the pivot of said blade and being coiled coincident with the pivotal axis of said blade, and iiieans for securing the ends of said strands rigidly in position.

In witness whereof I have hereunto subscribed my name in the presence of two subscribing witnesses.

STANLEY B. FREIBERG.