US1985573A

US1985573A - Mounting for circuit breakers

Info

Publication number: US1985573A
Authority: US
Publication date: 1934-12-25
Anticipated expiration: 1951-12-25

Description

Dec. 25, 1934. MALLQRY MOUNTING FOR CIRCUIT BREAKERS Filed Oct. 24, 1953 Patented Dec. 25, 1934 UNITED STATES MOUNTING FOR CIRCUIT BREAKERS Marion Mallory, Detroit, Mich, assignor to The Mallory Research Company, Toledo, Ohio, a corporation of Delaware Application. October 24,

9 Claims.

This invention relates to a mounting for circuit breakers, such as are usedin ignition systems for automobile motors.

In the operation of automobiles, a great deal of ignition trouble has resulted from the flashing, heating and fusing of the contact points of the circuit breaker, due largely to the creeping of the movable contact or to its rebound when the motor'isoperating at a comparatively high speed.

30 The object of the present invention is to provide a construction whereby such creeping or rebound will be effectually prevented.

In carrying'outmy invention, therefore, provision is made for accurately guiding the free 15 end of the circuit breaker arm in its opening and closingmovements, to insure perfect registration of the contact pointseven though the bearing for the lever arm may be loose or worn. At the same time, the spring which closes the contacts is so shaped and ten-sio ned' as to interpose a slight frictional resistance to the movement of the lever arm, resulting in a snubbing action, which effectively prevents rebound of the arm and the movable contact carried thereby.

The present specific embodiment of the invention will be more particularly described in connection with the accompanying drawing, in which,-

Fig. 1 is a plan view of one adaptation of the invention.

Fig. 2 is a front elevation thereof.

Fig. 3 is a perspective view of the circuit breaker and parts associated therewith.

Fig. 4 is a plan View of another adaptation of the invention.

Fig. 5 is a front elevation of the circuit breaker shown in Fig. 4.

Fig. 6 is a perspective view of the circuit breaker shown in Fig. 4.

As illustrated in the drawing, the invention is associated with an ignition timer, which comprises a rotatable shaft 8 disposed centrally of the shell 9. A circuit breaker cam 10 is secured to a sleeve 11 which is adjustable circumferentially of the shaft 8 and on which the rotor 12 is mounted.

In the adaptation shown in Figs. 1, 2 and 3, the stationary contact points 13 are mounted within the shell 9 and the movable contact points 14 are secured to opposite branches of a spring 15. The central portion of the spring is secured to a lug 16 within the shell 9 and each branch of the spring passes about a circuit breaker arm 1'7 of insulating material which is pivotally mounted on a pin 18. The tension of the spring nor- 1933, Serial No. 695,037 (01. 200 30) mally maintains each set of contact. points closed, except when they are opened by the action of, the cam 10 against the opposite end of the circuit breaker arm 17.

As stated above, a great deal of trouble in the operation of ignition circuit breakers, as heretofore constructed, has been caused by the creeping of the points, and this has been more apt to occur if the circuit breaker arm is long and has a tight spring tension. The tendency to creep, of course, is greatly increased if the pin 18 is slightly under size or the bushing worn.

In the present construction, however, the possibility of creeping is substantially eliminated by providing an accurate guide for the free ends of the spring 15. This guide comprises a dielectric or insulated spool 19 having flanges 20, between which the ends of the spring 15 are received, the distance between these flanges being substantially equal to the width of the spring, so that the only movement of the end portion or" the spring must be directly toward or away from the fixed contact point 14.

It is also to be noted that the upstanding flange of the lug 16, to which the spring 15 is secured, is inclined inwardly, so that the attached central portion of the spring is warped, thereby causing a downward pressure of the free ends of the spring against the lower flange 20 of the spool 19. This creates sufficient friction between the spring and the spool flange to effect a snubbing action which prevents rebound of the contact point 14 when it is closed by the cam 10.

In a four cylinder engine, the circuit breaker cam, of course, has only four lobes, as shown in 10 in Fig. 5, and in many cases a single straight circuit breaker arm 17 is used. In adapting the invention to this type of circuit breaker, the shape of the spring 15 is modified as illustrated in Figs. 4, 5 and 6, the other details of the invention remaining the same as in the first described adaptation.

From the foregoing description, it will be apparent that my invention effectively prevents both creeping and chattering of the contact points of the circuit breaker, with a resultant elimination of the flashing, heating and pitting, which is a most frequent cause of faulty ignition. It is also obvious that the invention is not limited to the specific embodiments herein described, but is capable of adaptation, within the scope of the appended claims, to any type of circuit breaker which is used on automobiles of the present day.

What I claim is:

1. In a circuit breaker for ignition timers, a

fixed contact point, a pivoted circuit breaker arm with a cooperating contact point carried thereby, a cam for opening the contacts, a spring for closing them, said spring having a free end extending beyond the free end of said arm, and means for accurately guiding the free end of the spring to prevent creeping of the movable contact point with reference to the fixed contact point.

2. In a circuit breaker for ignition timers, a fixed contact point, a pivoted circuit breaker arm with a cooperating contact point carried thereby,

a cam for opening the contacts, a spring for clos-' ing them, said spring having a free end extending beyond the free end of said arm, and means for frictionally engaging the free end of the spring, thereby efiecting a snubbing action to prevent rebounding of the movable contact point.

3. In a circuit breaker for ignition timers, a fixed contact point, a pivoted circuit breaker arm with a cooperating contact point carried thereby, a cam for opening the contacts, a spring for closing them, said spring having a free end extending beyond the free end of said arm, and means for accurately guiding the free end of the spring and at the same time exerting a frictional resistance against it to prevent creeping or rebounding of the movable contact point.

4. In a circuit breaker for ignition timers, a pair of contact points, a pivoted arm on which one of the contact points is carried, a cam for opening the contact points, a spring for closing them, and a guide for the side edges of the spring, said spring being warped laterally so as to exert pressure against one side of the guide, thereby effecting a snubbing action which prevents rebounding when the contact points close.

5. In a circuit breaker for ignition timers, a pair of contact points, a pivoted arm on which one of the contact points is carried, a cam for opening the contact points, a flat spring for closing them, and a guide having flanges between which the spring is accurately guided to prevent creeping of the contact points, said spring being warped so as to exert pressure against one of said flanges, thereby effecting a snubbing action which prevents rebounding when the contact points close.

6. In a circuit breaker for ignition timers, a pair of contact points, a pivoted arm on which one of the contact points is carried, a cam for.

opening the contact points, a flat spring for closing them, a lug to which one end of the spring is secured, said spring extending about said arm longitudinally thereof with its free end projecting beyond the same, and a spool having flanges between which the free end of the spring is guided to prevent creeping of the movable contact point with reference to the fixed contact point.

7-. In a circuit breaker for ignition timers, a pair of contact points, a pivoted arm on which one of the contact points is carried, a cam for opening the contact points, a flat spring for closing them, a lug to which one end of the spring is secured, said spring extending about said arm longitudinally thereof with its free end projecting beyond the same, and a spool having flanges between which the free end of the spring is guided to prevent creeping of the movable contact point with reference to the fixed contact point, the surface of the lug to which the spring is secured being inclined to the axis of the pivoted arm, thereby causing the free end of the spring to exert pressure against one of said flanges to effect a snubbing action which prevents rebounding when the contact points close.

8. An ignition circuit breaker comprising a base, a rocker arm mounted on said base, an elongated spring extending about said rocker arm and from both ends thereof, means for fixedly anchoring one end of the spring to said base, and means on said base for slidably holding the other end of the spring for the purpose described.

9. An ignition circuit breaker comprising a base, a rocker arm mounted on said base, an elongated spring extending about said rocker arm and from both ends thereof, means for fixedly anchoring one end of the spring to said base, and means on said base for slidably holding the other end of the spring, the last mentioned means comprising a stop with two shoulders thereon, said spring being adapted to slide between said shoulders.

MARION MALLORY.