US2035621A - Circuit breaker - Google Patents

Description

H. G. SMITH, JR ZWSEEI CIRCUIT BREAKER March 31, 1936.

Filed Nov. '7, 1934 INVENTOR Harry 6 sm/r/z J77 ATTORNEY Patented Mar. 31, 1936 UNITED STATES PATENT OFFICE CIRCUIT BREAKER Harry G. Smith, Jr., Union,

Edison-Splitdorf Corporation,

N. J., assignor to West Orange,

6 Claims.

This invention relates to circuit breakers particularly of the type used in connection with ignition systems for internal combustion engines, and may be used in connection with a magneto or battery system.

In either system of ignition, it is highly essential that the contact points of the circuit breaker make contact over the entire surfaces which are in engagement when the breaker is closed. In ignition circuit breakers, the movable element carries a bumper which is adapted to engage or be engaged by a cam member to open the contacts at the proper time. Due to the wear of the bumper and the cam or cams, and the contact points themselves, it becomes necessary after a time to adjust the contacts so that the breaker opens only a certain amount in order to obtain the best results.

In many types of ignition circuit breakers the stationary contact point is usually carried on an adjustable screw and when the screw is turned to make the adjustment previously referred to, the parallelism between the contact faces of the points is lost, and to bring these faces back into parallelism, the contacts have to be filed or sandpapered or otherwise operated on to bring back the parallelism of the contact faces. This is objectionable for the reason that in many types of circuit breakers very valuable material such as platinum and iridium is used, and a less expensive metal such as tungsten. Yet in each case this material is wasted and considerable time is lost in making adjustment, which while .5. it looks simple, is not readily carried out. 3

In Ratcliff Patent 1,305,165, issued May 27, 1919, there is shown and described a circuit breaker which overcomes, by a patent construction, the difficulties previously described. In the Ratcliff construction, however, a separate piece for carrying the stationary contact is required and it is mounted around the same axial center as the circuit breaker arm, so that its adjustable movement together with the movement of the circuit breaker arm, and consequently the points carried by these parts, are along the arc of the same circle.

I have found, however, that a much simpler breaker can be made without these points being movable on the same are to accomplish the same purpose; or, stated in another way, I have accomplished the main object of maintaining the parallelism of the contact faces while adjusting the distance of opening of the contacts, in a different manner than disclosed in the Ratcliff patent.

My invention will be readily understood by reference to the annexed drawing, wherein:

Figure 1 is a plan view of my improved type of circuit breaker included in a suitable support or breaker housing, together with a cam for 5 operating the movable part of the breaker.

Figure 2 is a section on the line 2-2 of Figure 1. Figure 3 is a view on the line 33 of Figure 1. Figure 4 is a view similar to Figure 1, but showing a modified form of means for mounting and 0 adjusting one of the circuit breaker members.

Figure 5 is a separate view of the breaker mechanism shown in Figure 4, but showing in dotted lines an adjusted position of the parts.

In the different views, I is a mounting mem- 15 her which may be generally referred to as a breaker housing having a lever 2 for shifting the mounting member to advance or retard position. Pivoted in any satisfactory manner as by a pivot screw 3, is a breaker member 4, the free 20 end of which has an outwardly projecting end or lug 5 to which is securely anchored a contact point 6 which may be of any suitable material satisfactory for use with the apparatus to which it is related. 26 The breaker member 4 has securely anchored thereto a pivot pin or stud l on which is mounted a movable breaker arm 8 carrying on its free end a contact 9 that is adapted to cooperate with the contact 6. The breaker arm 8 is insulated 0 from the piece or stud l as by a suitable insulator l8 so that current may be conducted to the breaker arm 8 through the spring H, which may have an extra current-carrying member associated therewith, both of which are connected to 5 a terminal stud l2 fastened to the mounting member I but insulated therefrom. The arm 8 carries the usual bumper l3 and is adapted to be engaged by cam I 4 carried on an operating shaft connected with the mechanism. The cam 40 I4 is preferably made of some self-lubricating material such as aggregates formed of finely divided metal and subsequently soaked in lubricant. The contacts 6 and 9 are normally held in closed position by the spring I l. 4

The breaker member 4 is provided with an oblong opening I5 to receive a locking screw l6 which is used to hold the member 4 in adjusted position. The breaker member 4 is also provided with a second elongated hole ll within which is positioned an adjusting screw having an eccentric head IE, so that as the head I8 is turned, it engages the side Walls of the hole I! to move the breaker member 4 about its pivotal screw 3.

It will be seen from this construction that since allelism of their contact faces.

the movable breaker arm 8 is carried on the breaker member 4, when the latter member is adjusted as above described, no change in the position of the contacts 6 and 9 takes place as the breaker arm 8 is moved simultaneously with the member 4, and consequently the contact points 6 and 9 maintain the same relative par- The reason for adjusting the breaker member 4 is, of course, so that the distance of the openings between the points 6 and 9 may be set to the desired distance. In other words, it is common practice to adjust the ignition circuit breaker so that the contacts open approximately twenty thousandths of an inch. This adjustment may vary somewhat from this figure in accordance with the type of apparatus with which the breaker is used. Furthermore, adjustment is needed to take up or compensatefor wear on the contact points and on the bumper I3 In the form of device shown in Figures 4 and 5, the breaker member 4, instead of being pivoted. in the manner shown in Figure l, is provided with an additional oblong hole [9 similar to I5, so that after the set screws l6 are loosened, the member 4 may be adjusted laterally and then the screws l5 tightened up, looking the member 4 in its newly adjusted position; but as before, the breaker arm 8 maintains its same relative position and no change in the parallelism of the faces of the contact points 6 and 9 takes place. This is clearly indicated by the tWo positions of the circuit breaker parts shown in Figure 5.

From what has been said,.it will be seen that the breaker member 4 and movable contact arm 8 constitute a unit assembly which can be put together entirely separate from the mounting member or house, or a breaker face plate some-- times used for carrying these par-ts. The arrangement thus provides a construction which will enable the fixed contact 6 carried on the lug 5 to be adjusted by slightly bending the lug 5 so as to bring the faces of the contact points into substantially perfect parallelism before any part of this assembly is put into the apparatus with which it is to be used, whereby, after it is assembled in the said apparatus, only the adjustment of the member 4 with respect to the cam is required. 7

What I claim is:

1. In a device of the character described, the combination of two cooperating members, one pivotally mounted on the other, and each carrying a contact for conjoint action one on the other, means for moving said pivotally mounted member to open and close said contacts, said one member, carrying the other pivoted thereto, being adjustable primarily for varying the amount of separation of the contacts.

2. In a device of the character described, the combination of a mounting member, a circuit breaker member carrying a contact and being adjustably mounted on said mounting member, an arm pivotally mounted on said breaker member and having a contact cooperating with said first-mentioned contact, the adjustable mounting of said circuit breaker member being primarily for varying the amount of separation of the contacts.

3. In a device of the character described, the combination of a mounting member, a circuit breaker member carrying a contact and being adjustably mounted on said mounting member, a post carried on said breaker member, an arm pivotally mounted on the post, said arm having a contact for cooperation with said firstmentioned contact, the adjustable mounting of said circuit breaker member being primarily for varying the amount of separation of the contacts.

4. In a device of the character described, the combination of a mounting member, a circuit breaker member carrying a contact and being shiftably mounted on said mounting member, a movable member carried on said breaker member and having a contact cooperating with said first-mentioned contact, the shiftable mounting of said circuit breaker member being primarily for varying the amount of separation of the contacts.

5. In a circuit breaker having cooperative contacts, means for opening and closing said contacts, means for retaining the contacts in para]- lelism while varying the amount of opening of the contacts'which comprises a shiftable member carrying one of the contacts and a member movably carried on said shiftable member and carrying the other contact, said breaker member being adjustable primarily for varying the amount of separation of the contacts.

6. In a device of the character described, the combination of amounting member, a circuit breaker member having a relatively stiff yet adjustable lug carrying a contact, said breaker member being adjustably mounted on said mounting member, a movable member carried on said breaker member and having a contact cooperating with the contact on said lug, said breaker member being adjustably mounted primarily for varying the amount of separation of the contacts.

' HARRY G. SMITH, JR.

Images