GB1577989A

GB1577989A - Pushbutton electric switch

Info

Publication number: GB1577989A
Application number: GB13712/78A
Authority: GB
Original assignee: Schoeller and Co Elektrotecnische Fabrik GmbH and Co
Current assignee: Schoeller and Co Elektrotecnische Fabrik GmbH and Co
Priority date: 1977-04-14
Filing date: 1978-04-07
Publication date: 1980-10-29
Also published as: IT1097053B; DE2716483A1; FR2387503B1; ES235262Y; DE2716483B2; DE2716483C3; BR7802280A; JPS5851649B2; ES235262U; JPS53128786A; IT7822132A0; FR2387503A1

Description

(54) PUSHBUTTON ELECTRIC SWITCH (71) We, SCHOELLER & CO ELEK TROTECHNISCHE FABRIK GmbH & Co. of Mörfelder Landstrasse 115-119, Postfach 701140, 6000 Frankfurt am Main 70, West Germany; a German body corporate do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a pushbutton switch having a snap-action mechanism, more especially a mains switch for colour television receivers and the like, in which the pushbutton slider and the contactcarrying slider are mounted one above the other oppositely displaceable in a housing on which the fixed contacts are secured, and mechanically interconnected via two torsion springs.

In a known switch the pushbutton slider has a guide groove and the insulating panel supporting the fixed contacts has a slot into which the contact-carying slider, supporting spring-mounted contact bridges in windows, projects. The torsion springs are located outside the housing and on the insulating plate and on the actuation free end of the switch. At the end of the pushbutton slider a holder for the springs is mounted which is provided with a slot for pressing onto a web of the pushbutton slider. The pushbutton slider and contact-carrying slider are biased towards one another by the upwardly projecting springs, so that, due to the friction caused thereby, a fast switching speed cannot be attained. Moreover, the friction reduces the life of the switch. The arrangement of the springs on the rear end of the switch also has the disadvantage that no additional contacts may be incorporated into the mains switch. Moreover, leads or laced wire harnesses in the receivers obstruct the exposed springs in their switching function.

It is therefore an object of the invention to seek to provide a switch in which the pushbutton sliders, contact-carrying sliders and springs are arranged in such a manner that they may be substantially totally enclosed ensuring a perfect guidance of the sliders in the switch housing and no pressure is applied between sliding parts so that maximum switching speed can be achieved.

According to the present invention there is provided a pushbutton electric switch having snap-action mechanism, more especially a mains switch for colour television receivers and the like, said switch comprising a pushbutton slider and a contactcarrying slider which are mounted one above the other in a housing supporting fixed contacts, said sliders being oppositely displaceable and mechanically interconneted by two wire overcentre torsion springs such that displacement of the pushbutton slider cuases displacement of the contactcarrying slider in the opposite direction. The contact-carrying slider being provided with two lateral extensions for guiding the contact-carrying slider and the pushbutton slider in the housing and the torsion springs, interconnecting with the two sliders, being located below the two lateral extensions of the contact slider.

The switch in accordance with the invention has the advantage that it is of simple construction and cheap to produce and, due to the minimum friction of the moving parts, has a high operating reliability and a long life. Its structure is such that additional contacts for increasing its possible uses may be inserted in the switch housing, In favourable futher development of the invention it is preferable to provide the torsion springs with right angle bends for insertion into bores or slots of the extensions of the contact-carrying slider and into bores or slots of the pushbutton slider. The pushbutton slider may be provided with a projection acting as a stop which projects into a recess of the housing. To attain auxiliary functions for the switch additional contacts may be provided in the region of the rear end of the housing, which contacts are actuated by the pushbutton slider or the contact-carrying slider and the connecting terminals of which face the same direction as the connecting terminals of the fixed contacts of the switch. The contact-carrying slider may be provided with an extension which can act on the springs of the additional contact(s). To enable the additional contact(s) to be readily interchanged and renewed, they are preferably mounted in a contact holder which is insertable in an aperture at the rear of the housing.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a longitudinal section through a mains switch in accordance with the invention having a contact slider acting on an additional contact; Figure 2 shows the switch of Figure 1 in the "on" position; Figure 3 is a cross-section through the switch taken on the line III-III of Figure 1; and Figure 4 is a mains switch in which the button slider acts on the additional contact.

A pushbutton switch according to the invention comprises: a housing 1 with fixed contacts 2, a pushbutton slider 3 with a return spring 4 and a pin 5 for mounting an actuating button; a contact-carrying slider 6 having contact bridges 9 and 10 springmounted by springs 7 and 8; torsion springs 11 and 12 which form the snap-action mechanism; and an additional contact 15 with a contact holder 16 located at the rear end of the switch. The contact-carrying slider 6 is provided with two lateral extensions 20 and 21, which guide the contactcarrying slider 6 and the pushbutton slider 3 in the housing 1. The two springs 11 and 12 engaging with the sliders 3 and 6 are located, horizontally, below the two lateral extensions 20 and 21 of the contact-carrying slider 6. The springs 11 and 12 are bent at right angles and engage by means of angled parts 17 and 18 in bores of the pushbutton slider 3 and the contact-carrying slider 6.

The pushbutton slider 3 is provided with a projection 22 acting as a stop, which projects into a recess 23 of the housing 1. The contact-carrying slider 6 has a longitudinal extension 25 which acts on the additional contact 15, which is normally open in the rest position, in such a manner that the contact is closed at the switching speed of the snap-action mechanism. The additional contact 15, provided as an additional switch (e.g. battery switch) for a further circuit, is mounted on a U-shaped contact holder 16 which is adapted to be inserted into an aperture 26 of the housing 1 and the holder 16 has a projection 27 which engages in a recess in the housing 1 so that it is readily removed from the housing 1 for insertion of an additional contact, for example, having a different function.

By suitable formation of the additional contact in the contact holder 16 a pin 28 of the pushbutton slider 3 may act on an additional contact 29 instead of the contactcarrying slider 6, as shown by Figure 4.

Instead of one additional contact several such contacts may be provided. The additional contacts provide a considerable modification possibility of the switch in accordance with the invention, so that it will be suitable for a variety of purposes. Unipolar or bipolar make, break, change-over or battery switching contacts may be used as additional contacts. A modification of the switch in accordance with the invention from bipolar to tripolar is possible without having to change the external dimensions, which is of particular advantage. The switch may then be soldered or connected from one side, since all the connecting lugs face in the same direction. The additional contacts are completely screened, inaccessible to external influences and securely integrated with the switch housing, and their mounting is simple and space saving.

A stop, not shown, in combination with a detent mechanism for the pushbutton slider ensures that the pushbutton slider has two possible switch positions.

WHAT WE CLAIM IS; 1. A pushbutton electric switch having snap-action mechanism, more especially a mains switch for colour television receivers and the like, said switch comprising a pushbutton slider and a contact-carrying slider which are mounted one above the other in a housing supporting fixed contacts, said sliders being oppositely displaceable and mechanically interconnected by two wire overcentre torsion springs, such that displacement of the pushbutton slider causes displacement of the contact-carrying slider in the opposite direction, the contactcarrying slider being provided with two lateral extensions for guiding the contactcarrying slider and the pushbutton slider in the housing and the torsion springs, interconnecting the two sliders, being located below the two lateral extensions of the contact slider.

2. A pushbutton electric switch according to claim 1, in which the springs are provided with right angle bends for insertion into bores or slots of the lateral extensions of the contact-carrying slider and in bores or slots of the pushbutton slider.

3. A pushbutton electric switch according to claim 1 or 2, in which the pushbutton

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. projection acting as a stop which projects into a recess of the housing. To attain auxiliary functions for the switch additional contacts may be provided in the region of the rear end of the housing, which contacts are actuated by the pushbutton slider or the contact-carrying slider and the connecting terminals of which face the same direction as the connecting terminals of the fixed contacts of the switch. The contact-carrying slider may be provided with an extension which can act on the springs of the additional contact(s). To enable the additional contact(s) to be readily interchanged and renewed, they are preferably mounted in a contact holder which is insertable in an aperture at the rear of the housing. The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a longitudinal section through a mains switch in accordance with the invention having a contact slider acting on an additional contact; Figure 2 shows the switch of Figure 1 in the "on" position; Figure 3 is a cross-section through the switch taken on the line III-III of Figure 1; and Figure 4 is a mains switch in which the button slider acts on the additional contact. A pushbutton switch according to the invention comprises: a housing 1 with fixed contacts 2, a pushbutton slider 3 with a return spring 4 and a pin 5 for mounting an actuating button; a contact-carrying slider 6 having contact bridges 9 and 10 springmounted by springs 7 and 8; torsion springs 11 and 12 which form the snap-action mechanism; and an additional contact 15 with a contact holder 16 located at the rear end of the switch. The contact-carrying slider 6 is provided with two lateral extensions 20 and 21, which guide the contactcarrying slider 6 and the pushbutton slider 3 in the housing 1. The two springs 11 and 12 engaging with the sliders 3 and 6 are located, horizontally, below the two lateral extensions 20 and 21 of the contact-carrying slider 6. The springs 11 and 12 are bent at right angles and engage by means of angled parts 17 and 18 in bores of the pushbutton slider 3 and the contact-carrying slider 6. The pushbutton slider 3 is provided with a projection 22 acting as a stop, which projects into a recess 23 of the housing 1. The contact-carrying slider 6 has a longitudinal extension 25 which acts on the additional contact 15, which is normally open in the rest position, in such a manner that the contact is closed at the switching speed of the snap-action mechanism. The additional contact 15, provided as an additional switch (e.g. battery switch) for a further circuit, is mounted on a U-shaped contact holder 16 which is adapted to be inserted into an aperture 26 of the housing 1 and the holder 16 has a projection 27 which engages in a recess in the housing 1 so that it is readily removed from the housing 1 for insertion of an additional contact, for example, having a different function. By suitable formation of the additional contact in the contact holder 16 a pin 28 of the pushbutton slider 3 may act on an additional contact 29 instead of the contactcarrying slider 6, as shown by Figure 4. Instead of one additional contact several such contacts may be provided. The additional contacts provide a considerable modification possibility of the switch in accordance with the invention, so that it will be suitable for a variety of purposes. Unipolar or bipolar make, break, change-over or battery switching contacts may be used as additional contacts. A modification of the switch in accordance with the invention from bipolar to tripolar is possible without having to change the external dimensions, which is of particular advantage. The switch may then be soldered or connected from one side, since all the connecting lugs face in the same direction. The additional contacts are completely screened, inaccessible to external influences and securely integrated with the switch housing, and their mounting is simple and space saving. A stop, not shown, in combination with a detent mechanism for the pushbutton slider ensures that the pushbutton slider has two possible switch positions. WHAT WE CLAIM IS;

1. A pushbutton electric switch having snap-action mechanism, more especially a mains switch for colour television receivers and the like, said switch comprising a pushbutton slider and a contact-carrying slider which are mounted one above the other in a housing supporting fixed contacts, said sliders being oppositely displaceable and mechanically interconnected by two wire overcentre torsion springs, such that displacement of the pushbutton slider causes displacement of the contact-carrying slider in the opposite direction, the contactcarrying slider being provided with two lateral extensions for guiding the contactcarrying slider and the pushbutton slider in the housing and the torsion springs, interconnecting the two sliders, being located below the two lateral extensions of the contact slider.

slider is provided with a projection acting as a stop, which projects into a recess of the housing.

4. A pushbutton electric switch according to any of the claims 1 to 3, in which at the rear of the- housing additional contacts are provided which are actuated by the pushbutton slider or by the contact-carrying slider and the connecting terminals of additional contacts extend in the same direction as the connecting terminals of the said fixed contacts of the switch.

5. A pushbutton electric switch according to claim 5, in which the contact-carrying slider is provided with an extension which acts on the springs of the additional contact at the switching speed of the snap-action mechanism.

6. A pushbutton electric switch according to claim 4 or 5. in which the additional contacts are located in a contact holder which is inserted engageable in an aperture at the rear of the housing.