Electric switch with an actuator

Abstract

An electric switch has a housing with an upper surface through which a actuating plunger extends at a position close to a side surface. The actuating plunger is arranged to operate a switching element disposed inside the housing. An actuating lever is fixed to the side surface adjacent the plunger such that the actuating lever extends over and beyond the upper surface of the housing. A stop for the actuating plunger is arranged inside the housing. With this switch the actuating travel is extended solely in relation to the switch. Furthermore a long over-travel exists following switching, wherein any forces which might occur through improper use in relation to the switch do not cause any damaging effects to the switching element.

Claims

1. An electric switch with a housing comprising an upper surface through which a actuating plunger extends and an actuating lever fixed to the housing and arranged to operate the actuating plunger, wherein the actuating plunger is disposed adjacent a side surface of the housing and in that the actuating lever is fixed to said side surface, wherein the actuating lever extends across and beyond the upper surface of the housing and that a stop for the actuating plunger is arranged inside the housing, and wherein the upper surface of the housing is deformable when the actuating lever is forced by an external force to move downwardly and depress the actuating plunger.

2. The switch of claim 1, wherein the actuating lever is inserted into a gap arranged in the housing in an area of said side surface.

3. The switch of claim 2, wherein the actuating lever comprises at least one barb in the area provided for insertion into the gap.

4. The switch of claim 1, wherein the actuating lever is configured as a spring made of a resilient material.

5. The switch of claim 4, wherein the spring of the actuating lever is manufactured of metal.

6. The switch of claim 1, wherein the actuating lever comprises at least one material weakening in an area extending away from its articulation with regard to the actuating plunger.

7. The switch of claim 6, wherein the material weakening is formed by lateral indents in the extension of the actuating lever.

8. The switch of claim 1, wherein a spring switching element is arranged between the actuating plunger and the stop inside the housing.

9. The switch of claim 2, wherein the actuating lever has a bend in a portion corresponding to an edge between the said side surface and the upper surface of the housing, a portion of the bend is disposed within the gap, and a remaining portion of the bend is outside of the gap.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) A preferred embodiment of the invention will now be described, by way of example only, with reference to figures of the accompanying drawings. In the figures, identical structures, elements or parts that appear in more than one figure are generally labeled with a same reference numeral in all the figures in which they appear. Dimensions of components and features shown in the figures are generally chosen for convenience and clarity of presentation and are not necessarily shown to scale. The figures are listed below.

(2) FIG. 1 is a perspective view of an electric switch according to the invention;

(3) FIG. 2 is a side view of the switch of FIG. 1; and

(4) FIGS. 3 to 6 are sectional views of the switch of FIG. 1, in different switching positions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) The switch of FIG. 1 comprises an approximately rectangular housing 1. The housing 1 has side surfaces and an upper surface 2. An actuating plunger 3 is arranged in the upper surface 2. The actuating plunger 3 is positioned close to one of the side surfaces, and in the area of this side surface an actuating lever 4 is attached to the housing 1. The actuating lever 4 extends above, over and beyond the upper surface 2 of the housing 1. In an area between the point of contact of the actuating lever 4 with the actuating plunger 3 and the free end of the actuating lever 4, the actuating lever 4 comprises indents 5, forming a narrowed and thus more flexible portion of the lever. Contacts 6 protrude from the underside of the switch.

(6) Preferably, the actuating lever is a strip of resilient metal that is pre-shaped and mounted to the housing by being inserted in a gap 10 in the side of the housing. It has a bend in a portion corresponding to an edge between the said side and the upper surface of the housing. This bend creates an articulation point or hinge about which the actuating lever moves or pivots under normal operating conditions.

(7) The switch is shown with three contacts 6, common, upper and lower, extending through the bottom of the housing and forming a common terminal, a normally closed terminal and a normally open terminal, respectively.

(8) FIG. 2 shows the actuating lever 4 resting on the actuating plunger 3. This rest position of the switch is also shown in FIG. 3. A spring switching element 7 arranged inside the housing 1 is supported against the upper contact 6.

(9) In FIG. 4 the actuating lever 4 has been moved downward by an extent indicated by arrow S, this movement was transferred to the actuating plunger 3, whereupon the spring switching element 7 has detached itself from the upper contact 6 and changed into another switching state, optionally in contact with the lower contact 6. The upper surface 2 of the housing 1 has become slightly indented.

(10) In FIG. 5 the actuating lever 4 has been moved by a greater extent as indicated by arrow S. Thereupon the actuating plunger 3 was moved towards a stop 8 arranged inside the housing 1. The stop 8 limits the possible movement of the actuating plunger 3 in such a way as to prevent damage to the spring switching element 7 and contacts 6. The upper surface 2 of the housing 1 has become somewhat more indented than shown in FIG. 4.

(11) FIG. 6 shows an over-stroke or possible over-travel of the actuating lever 4 due to the impact of even greater forces indicated by arrow S. The actuating lever 4 is nearly touching the edge 9 of the housing 1 formed by the upper surface 2 and a side wall. The upper surface 2 is still indented, and the actuating plunger 3 is still resting on the stop 8. If the actuating lever 4 is moved still further along arrow S the actuating lever 4 will come to rest on the edge 9. Then the point of leverage for the actuating lever 4 will shift its position. In FIGS. 3 and 4 this point of leverage is the first corner of the housing adjacent to the attachment of the actuating lever. In FIGS. 5 to 6 this point of leverage lies on the actuating plunger 3, for a further movement of the actuating lever 4 the point of leverage will shift again to the edge 9. This causes the effective length of the actuating lever 4 to be shortened, in any case on the portion of the actuating lever 4, which can still be acted upon by the force S. The shorter actuating lever 4 can now oppose the force S with a greater force.

(12) In order to ensure that the actuating lever 4 is connected securely with the housing 1, the actuating lever 4 is inserted into the gap 10 of the housing 1, the actuating lever 4 additionally comprises a barb 11 to prevent accidental removal of the actuating lever 4 from the gap 10.

(13) In the description and claims of the present application, each of the verbs comprise, include, contain and have, and variations thereof, are used in an inclusive sense, to specify the presence of the stated item or feature but do not preclude the presence of additional items or features.

(14) It is appreciated that various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

(15) The embodiment described above is provided by way of example only, and various other modifications will be apparent to persons skilled in the field without departing from the scope of the invention as defined by the appended claims.