US2405679A - Push-button switch - Google Patents

Description

PUSH BUTTON-SWITCH Filed Sept. 1l, 1944 G. lA. wAHLsTRM n' ,405,679

Patented Aug. 13, 1946 Gustaf Adolf Whlstrm, Akeshov, signor to Telefonaktiebolaget L.

Stockholm,

Sweden, as- M. Ericsson,

Sweden, a company of Sweden Application September 11, 1944, Serial No. 553,609 In Sweden July 30, 1941 4 Claims.

The invention relates to a push button switch provided with an operating finger pivoted in the push button, said linger being adapted upon depression of the button alternately to operate a cradle to two different positions, said cradle being pivoted in the base. It is an object of the invention to provide a switch of the present type giving an effective, momentary closing and interruption of the current and preventing the stationary contacts from being burnt when the current is interrupted.

The invention will be more closely described with reference to the enclosed drawing.

Fig. 1 is a vertical section through the push button axis.

Figs. 2 4 are vertical sections along the line A-A in Fig. 1 showing the elements of the switch in different positions. Fig. 5 is a front View of the contact arms and the stationary contacts when the arms are in the position shown in Fig. 2.

A push button I is movably arranged in two standards 2, a two-armed operating finger 3 of insulating material being pivoted in the push button. Upon depression of the push button the two arms of the operating finger cooperate with the cradle 6, said cradle being mounted to oscillate on the pivot 'I in the base 5. The cradle 6 consists of two sector-formed plates 6a, 6b and a cross-piece 8. The plates are each provided with cams 9, I0. The cradle is turned in a known manner per se from one end position to the other upon depression of the button I, A double, twoarmed lever I3 is mounted on the pivot I2 in the cradle 6, the arms I3a., I3b thereby being provided with contacts I4 cooperating with stationary contacts I5, each of said contacts being provided with a plane surface II for making the circuit (making-position) and a surface for breaking the circuit (breakingposition), said last mentioned surface being provided with a swell I6. The lever I3 is operated by a device I'I consisting of two rollers I'Ia and I'Ib fastened on a pivot I8. The pivot I8 is mounted in an arm I9 being movable in the direction of the depression of the button in notches 20 in the base. Said arm I9 also carries a bar 23 of insulating material, a coil spring 25 being arranged around said barand xed between the cross-piece 26 of the arm 3 and a flange 24. The rollers I'I consequently engage the lever I3 under spring tension and on movement of the arm 3 the roller I'Ia will roll on the lever I3a and the roller I'Ib on the lever I 3b.

Fig. 2 shows the lever I3 in the making position, the cradle 6 thereby occupying its right end- Ylus position. The rollers I I thereby press against the left portion of the lever I3 and the contact device I4 takes the making position II. If the button is now pressed down, the cradle 6 is turned round the pivot 'I to the left as shown in Fig. 3 and the rollers I'I thereby roll on the lever I3, pressing against the part of the lever I3 lying to the right of the pivot I2 in such a way that this part of the lever gets a turning moment directed downwards. The contact member I4 on the lever I3 thereby has been brought from the making position II to the breaking position I6 as appears from Figs. 2 and 3. This displacement happens immediately before breaking of the circuit. When the different elements have obtained the positions shown in Fig. 3, the part of the lever I3 lying to the right of the pivot I2 will suddenly be turned downwards thereby causing the interruption of the current. The cradle 6 is thereby turned to the position shown in Fig.

4. Said displacement of the contact member I 4' from making-to breaking position is very advantageous since the contact plate I5 then can not be burnt in the making position. The lever I3 thus performs an angular movement in relation to the contact plate at the breaking of the circuit. On account of this movement it is possible to provide the contact plate with the above mentioned swell I6 inthe breaking position. The contact springs are thereby more tensioned in this position and the breaking of the circuit will occur more quickly. Upon repeated depression of the push button the arm 3 will cooperate with the edge I0 of the cradle thereby turning the cradle to the position shown in Fig. 2. The rollers II are thereby rolling along the lever I3 from the position shown in Fig. 4 until they occupy such a position on that part of the lever I3 lying to the left of the pivot I2, that a turning moment is obtained which is sulicient to turn the lever I3 and the cradle 6 to the positions shown in Fig. 2.

Through thefcombination of cradle 6 and the lever I3 which is carried by a pivot I2, mounted in the upper part of said cradle and being moved on the turning of the cradle 6, it also is rendered possible to make the base very low through maintaining the remaining ordinary dimensions.

I claim:

1. A push button switch comprising a base, a push button, a cradle pivotally mounted in the base, stationary contacts on said base, means operable during successive actuations of said button to alternately turn said cradle into two difthe sector-formed (from one position to the other.

2. A push button switch as claimed in claim 1 wherein said spring meansnormally tends to restore the push button to its initial position.

3. A push button switch as claimed in claim 1 wherein said spring means includes a bar movable in the direction of movement of the push button, a roller on said bar engaging said lever, and a spring operable to apply said roller to said lever and to restore the push button to its initial position. y

4. A push button switch as claimed in claim 1 wherein Vat least said stationary contacts are provided with raised portions coacting with the contact members at the moment the contact between Y-saiclcontacts and contact members is broken.

GUsTAF ADOLF WHLsTRM.

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