US1738764A - Switch construction - Google Patents

Description

Dec. 10, 1929.

Filed A ril l. 1927 II/L l/ Petentet i men as, i222 CGETSTEIUGTIQE Appticetion riled t,

' @ur invention relates to an improved switch construction such as is commonly mounted on. the steering wheel of motor vehicle to actuate the horn or warning signal lit has for its principal object the provision of a switch of simple and inexpensive con-- struction in which the hand button is independent of the electricai circuit,- but which will engage contact mechanism properly insulated and enclosed to conceal any sparking that may occur between the contacts.

A. second object is to provide a switch con struction in which the gap between the fixed and movable contact members may he made small and yet exact. In constructions where the width or the gap is dependent upon the relation or parts which may be disassembled. there is apt to be considerable variation and the gap has to be made comparatively large.

A stilliurther object is to provide a switch in which the normal position oi the button is determined by a wide flat surface of comparatively large diameter. This will serve to always hold the button in a straight posi tion with respect to the steering wheel instead of permitting the button to assume various tilted positions which detract from its appearance.

With the above and other objects in View, our invention. will be more clearly understood by referring to the specification and accompanying drawings, in which:

Figure 1 is a fragmentary section through a steering wheel, showing our improved switch construction associated therewith.

Figure 2 is a section taken on the line 22 of Figure 1.

Figure 3 is a perspective detail view of one of the parts.

The numeral is used to indicate a steering wheel upon which is carried a control 7 member 12 and a cap 14. This cap is provided with a recess 16 into which fits a switch base 18 made of any suitable insulating material. Molded into this base is a stationary contact member 20 having an aperture 22 adapted to receive the end of a wire 24 whichextends down through the hollow steering column and is connected with the horn. This edge.

Serial lilo. 122,233

wire is heid in place in member 20 by a screw 26 threaded into the member 20..

Secured to the base 18 by tongues 28 bent into grooves 30 is a cup-shapeol-member 32 within which is housed the switch mechanism. A. hand operable button 34 has a shanlr portion 36 which extends through an opening 38 in the cup-shaped member. Secured to the shank portion 36 by means of hollow rivet 40 imbedded in the button, is a frat washer 42 which seats against portion 44 of the cup-shaped member on the inside thereof to iimit the upward movement of the button. The washer 42 rests on top oi a dished disc 46 which is just enough smaller in diameter than the inside of the cup-shaped member 82 to permit free axial movement. A contact member 48, adapted to engage the stationary contact member 26 when the button is depressed, is riveted at its upper end in a centrai orifice in the dished center or" the disc 46. This movable contact member passes through a comperatively close fitting openlng 5G in a base washer 52 which is clamped between the base 18 end the cupshaped member'32. it compression spring 54 bears against the base washer 52 and the disc 46 to normally hold the contact members apart, The assembly is held in place in the recess 16 of the cap l4 by means of screw 56 which passes through the cap and is threaded into 2. lug 58 on the cup-shaped member. i

In operation, the button may be depressed by touching it either in the center or at the In the latter case it will tilt or rock about a pivot point where the Washer 42 bears against the portion 44. The opposite side of the washer 42 will then engage the disc 46 and force the latter down making a, contact between the member 48 and the member 20.. Due to the fact that the member 48 is uided by washer 52 and is held in disc 46 whiche-n ages the inside of cup-shaped member 32, it is impossible for member 48 to move in an direction except in a straight path up an down. Thus it always makes contact with. member 20 in exactly-the same manner and with the same amount of movement. The electric current flows from the wire 24 and contact 20 to the contact 48, spring 54, base washer 52, lug

58 of the cuprshaped member 32 andf'screw 56 which might cause the button to assume a tilted or crooked position, thus sppilipg its appearance.

As the width of the gap between the contact members 20 and 48 is determined solely by the de th of the cup-shaped member 32,

it is possi 1e to make this gap smaller than .usual, because this depth may be depended upon to be always the same, whereas if the width of the gap de ended upon how various Earts were assemble, in the cap 14 there might e considerable variation between diiferent switches; Iifthe latter case it would be neces-' sary to-provide a fairly large gap to take care of all conditions. A small gap is desirable because the horn can be operated quicker than when a large gap is provided.

Another advantage in our construction is that due to the fact that a comparativel large movable contact member is provide there is less damage done by sparking when breaking the circuit. When small areas are in contact they are apt to be burnt away, thus spoiling the contacts by burning, changing the width of the gap and varying the opera tion of the switch- A still further advantage is that in our construction the contact members are enclosed in a housing which is held in the recess 16 of the cap 14. This effectively encloses and hides any spark that may occur when the contact members separate and prevents the possibility of its being seen. It is thought from the foregoing taken in connection with the accompanying drawing that the construction and operation of the device will be apparent to those skilled in the art, and that various changes in size, shape, and proportion and details of construction may be made without departing from the spirit and scope of the appended claims.

We claim:

1. A switch construction comprising an insulating base, a cup-shaped member secured to said base, a washer having a central opening, a movable contact member passing through said opening, and a disc to which said contact member is secured, said disc fit: ting within said cup-shaped member and co operating with said central opening to preggnt rocking movement "of said contact memr.

2. A switch construction comprising an in sulating base including a stationary contact member, a cup-shaped member secured to said base, a washer having a central opening,

,disc fitting within said cup-shaped memberi ;a movable contact member secured in sai base, a base washer having a central opening,

said washer being held between said base and said cup-shaped member, a button,a flat washer secured'to said button, a disc, a movable contact member held in said disc and guided by said opening, and a spring serving to normally keep said contact members apart and to seat said flat washer against said cupshaped member.

4'; A switch construction comprising an insulating base including a stationary contact member, a cup-shaped member secured to said base, a base washer having a central opening, a movable contact member passingl through said opening, a disc to which sai movable contact member is secured, said disc fitting within said cup-shaped member and co-operating; with said central opening to.

prevent roc ing movement of said movable contact member, a hand operable button, and a washer secured to said button and fitting within said cup-shaped member, said button and the last-named washer being arranged to permit rocking movement to engage said disc and said movable contact member.

In testimony whereof I afiix my signature.

HARRY C. DOANE. In testimony whereof I aflix my signature.

LLOYD BLACKMORE.

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