US2777909A - Pre-positioned contact set - Google Patents

Description

S. WEIL PRE-POSITIONED CONTACT SET Jan, 15, 1957 Filed Feb. 3, 1955 INVENTOB 50 man, Wzl

iwzw/ ATT RNEY v PRE-POSITIONED CONTACT SET Solomon Weil, Jersey City, N. J., assignor to Kern Manufactoring Company, Inc., a corporation of New Jersey Application February 3, 1955, Serial No. 485,910

' 2 Claims. Cl. 200-31 My invention relatesto contact or point sets commonly used in ignition systems of internal combustion engines,

and more particularly to a pre-positioned contact set.

Ignition contact points generally comprise a spring biased movable arm and a stationary bracket, each provided with contact buttons, all supported on a breaker plate in the distributor. These parts are separately installed, requiring considerable skilled labor in the assembly and adjustment of the parts, and in establishing the electrical connections thereto.

With the present forms of construction, it is difiicult to assemble and install the component parts. For example, the spring pressure forces the bracket and the contact arm to become misaligned, making installation on the breaker plate diificult and inaccurate.

An object of the invention is to simplify the construction and arrangement of the parts to permit prepositioning the component parts, and thus permit installation on the breaker plate as a unit, thereby avoiding the time and skill required for separate installation and subsequent alignment.

I accomplish these and other objects and obtain my new results as will be apparent from the device described in the following specification, particularly pointed out in the claims, and illustrated in the accompanying drawing in which:

Fig. l is a top plan view of a typical breaker plate with the pre-positioned contact set of my invention installed thereon.

Fig. 2 is a side elevation thereof.

Fig. 3 is a sectional view taken in the plane 33 of Fig. 1.

Fig. 4 is a sectional view taken in the plane P4 of Fig. 2.

Fig. 5 is a top plan View of one end of the bracket.

Fig. 6 is a plan view of one end of the spring.

In Fig. 1 of the drawing, I have illustrated a typical breaker plate 10, one of the many types known, and it will be understood that my invention is adapted to be used with other types. Upon the breaker plate is mounted the condenser 12, with ground lead 14, primary lead 16, and a bracket 18 upon which is mounted a contact arm 20.

The bracket is apertured at 22 and 24 to receive bolts 26 and 28 for adjusting and attaching the bracket to plate 10. The apertures are angularly disposed and elongated to make possible adjustment in the position of the bracket on the plate, for controlling the dwell period.

One end of the bracket is provided with an upstanding flange 30 having a contact button 32 aifixed thereto. Another flange 34 is provided, to which is affixed a fiber insulating support 36 by rivet 38, as shown in Fig. 4. The lead wire 40 from the condenser 12 is connected to primary lead 16, on terminal post 42, as will be further described.

The contact arm comprises the button 44 (engaging button 32 of the bracket 18), rubbing block 46 and spring 48 which is mounted to terminal post 42.

The distributor cam (not shown) operating on the United States Patent 2,777,909 Patented Jan. 15,, .1957

. 2 rubbing block, opens the contact buttons against action of spring 48 which may be conductively secured to the contact by the same rivet 50 which holds the rubbing block to the contact arm.

The contact arm swings on its insulating bushing 52 secured tightly to the contact arm. The latter may be made of sheet metal folded along edge 54 and outwardly flanged as at .56 to receive the bushing in the aperture .8- h ge p rtions 56 are pressed about the bushing to anchor it securely, as shown in Fig. 3.

The contact arm and associated bushing ith .its exposed inner surface are fitted .over .a pivot post 60,, which is riveted as at 62 against shoulder 64 of the pivot post to the breaker plate 1.0. In order .to pre-align the position of the contact arm with respect to the bracket 18; a projecting retainer comprising the sleeve 66 is welded as at 6,8, .or otherwise formedon the bracket about aperture 70 therein. In the mouth of the sleeve .66, a flanged insulating retainer72 is pressed fitted to insure that the adjacent flange 5.6 of the contact arm is properly insulated from sleeve 66. The lateral surface of he bushing engages the integrally formed projecting retainer. "Ihe pivot post is provided with a shoulder 74 to position the contact arm bushing 52 thereon.

The fixed end of spring 48 may be slotted, as at 76, and is secured to the terminal post 42. A form of such securement is shown in cross-section in Fig. 4. The terminal post 42 is provided with a head 78 fitting against insulating support 36. A deformable flange 80 may be formed on the other side of the spring to permanently secure the post and spring against the insulating sup port. The other end of post 42 is threaded, as at 82, to receive the primary lead 16, and condenser lead wire 40 by means of nut 84. The electrical conductivity of the spring may be supplemented by a strip of flexible copper (not shown).

The internal diameter of the retainer 72 is sufficiently larger than the external diameter of the contact arm bushing 52 to minimize friction contact during operation. A side clearance of about .004" has been found satisfactory without loss of the pre-positioned benefits.

By this construction it is possible to pre-position the contact arm on the bracket so that both the contact arm and the bushing are held in operating position with respect to the bracket, and all parts unitarily positioned with respect to the pivot post. Thus, the buttons are properly and fixedly aligned with respect to each other. All that is necessary thereafter is to attach the bracket and assembled parts on the breaker plate and adjust its position so that the rubbing block is engaged with the cam to open and close the contact buttons with the proper spacing to control the dwell period. Installation of the parts is easier, and much of the labor ordinarily required to properly install and align these parts is eliminated. By manufacturing the parts as a unitary assembly, it is thereafter unnecessary to adjust the spring tension and separately align the parts at the time of installation on the breaker plate. The electrical connections are easier to make, and without danger of knocking the parts out of alignment. The spring tension is factory controlled and the alignment is with factory precision, and with an accuracy difiicult to obtain in the field.

My construction makes it unnecessary to touch the spring upon installation of the contact set into the distributor.

My construction obtains the foregoing advantages with out increasing the diameter of the parts which rotate one on the other. Increasing the diameter increases the friction and thus reduces the eiiiciency of the contact set.

Another advantage is the ability to function as desired, without increasing the weight of the moving parts. By using a permanently positioned terminal post 42, I lessen the possibility of loose connections and facilitate the attachment of the primary and condenser leads. By fixing the contact spring permanently to the bracket, I have made a unitary assembly of contact arm and bracket, and fixed a predetermined tension in the spring when assembled.

I have thus described my invention, but I desire it understood that it is not confined to the particular forms or uses shown and described, the same being merely illustrative, and that the invention may be carried out in other ways without departing from the spirit of my invention, and, therefore, I claim broadly the right to employ all equivalent instrumentalities coming within the scope of the appended claims, and by means of which, objects of my invention are attained and new results accomplished, as it is obvious that the particular embodiments herein shown and described are only some of the many that can be employed to attain these objects and accomplish these results.

I claim:

1. A contact set for installation onto the breaker plate of an ignition system having a conventional cylindrical pivot post extending therefrom, said contact set comprising a contact arm provided with a spring, contact button, rubbing block and an insulated pivot bushing fixed to said arm having a lateral surface and an inner exposed surface for mounting directly on the pivot post for rotation thereon, and a bracket having a contact button, an insulated terminal and an aperture through which the pivot post may extend, said bracket provided with an integrally formed projecting retainer positioned about said aperture and engaging the outer lateral surface of the contact arm insulating bushing for locating the bushing directly over said aperture, whereby when said contact set is positioned over the breaker plate, the pivot post will enter the aperture of the bracket and automatically center itself in the pivot bushing with the contact button in exact position for use. I

2 The contact set of claim 1 wherein the projecting retainer comprises a tubular portion encircling the pivot bushing.

References Cited in the file of this patent UNITED STATES PATENTS 2,290,078 Thomas July 14, 1942 2,518,560 McCormick Aug. 15, 1950 2,635,150 Spang Apr. 14, 1953 2,697,762 Burch Dec. 21, 1954

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