GB2051481A

GB2051481A - Electrical switch

Info

Publication number: GB2051481A
Application number: GB7921799A
Authority: GB
Original assignee: AB Electronic Components Ltd
Current assignee: AB Electronic Components Ltd
Priority date: 1979-06-22
Filing date: 1979-06-22
Publication date: 1981-01-14
Also published as: ES8101811A1; DE3022380A1; JPS566328A; ES492677A0; FR2460031A1; IT8012575A0; BE883926A; IT1133447B

Abstract

In order to enable a push button mains switch to be remotely operable from the "on" to the "off" position, there is provided an electromagnetically operated arm (30) which sweeps a trip catch (9) out of the "on" position to allow a contact carrying slide (2) to return the "off" position under the influence of its spring (3). The electromagnet may have a coil (20) and may be operated by any suitable power supply under a remote control. <IMAGE>

Description

SPECIFICATION Electrical switch This invention relates to push button switches.

Push button switches of the trip catch type, i.e. push to activate, push to deactivate, are frequently used as mains (or other power supply) switches in domestic entertainment equipment and other applications. Remote control is available for channel switching, volume control and various other functions, and there is a demand for a switch which could be remotely operated to effect switching off of a T.V. set or other appliance from a remote location, by deactivating the power supply.

According to this invention there is provided a push button electrical switch having a spring loaded slider adapted to be retained in activated and de-activated positions by a strip catch engageable with a cam track traversed by the trip catch as the slider is successively depressed, in which means is provided for displacing the trip catch in the cam track in one of the said positions without depression of the slider so as to release the slider to return to the other position under its spring loading.

Normally, the displacing means will operate to displace the trip catch from the activated position.

A preferred mode of operation is to have a solenoid-operated displacing means which may be energized from a remote location using power derived from the power source.

The displacing means may be spring returned.

The invention will be further described with reference to the accompanying drawings which show a preferred embodiment of the invention, and in which: Figure 1 is a side elevation of a preferred form of switch according to the invention with some parts cut away and others which are omitted from the subsequent figure, shown dotted; Figure 2 is a plan view of the switch of Fig.

1; Figure 3 is a bottom plan view of the switch of Figs. 1 and 2; Figure 4 is an end elevation of the switch of Figs. 1, 2 and 3; and Figure 5 is an enlarged plan view illustrating the operation of the trip catch.

Figs. 1 to 4 show a switch body 1 which houses a slide loaded outwardly by a spring 3 and actuable by means of a push button 4 formed integrally with the slide 2 and projecting out of the body 1. In addition, Fig. 1 shows an upper body moulding 5 carrying fixed contacts 6 and surmounted by a cover 7. These components are shown dotted only and are omitted from the remaining figures as their functions are generally conventional and form no part of the present invention. It suffices to say that pairs of fixed contacts 6 on either side of the upper body moulding 5 are bridged by contacts carried by the slide 2 when the latter is in an activated position, and are not so bridged when it is in a de-activated position.According to the function of the switch, it is possible for different sets of contacts to be bridged in two different positions, but when the switch is a power switch for a domestic entertainment equipment, such as a television sets, this will not be the case.

The slide carries, as is conventional, a cam track 8 which is co-operable with a trip catch 9 in the form of a length of steel wire pivoted at its end 10 in the body 1, and having a down-turned end slidable in the track. The track is shown in more detail in Fig. 5,-with the down-turned end of the trip catch indicated at varying positions by different reference numerals. The cam track 8 is formed between a peripheral wall 11 and an island 1 2. The normal operation is that in the off or de-activated position, the trip catch is in the position 1 3 and a first depression of the push button 4 causes it to travel round the cam track as indicated by the arrows to a first hole position 14.Release of the push button 4 allows the spring 3 to return the slide and the trip catch comes to rest in the on position 1 5 against the island 1 2. This position is that which is illustrated in Fig. 2. A succeeding depression of the push button 6 causes the trip catch to move to the second hold position 16, and subsequent release allows the spring to return the slide to its outermost position while the trip catch returns, following the arrow, to the off position 1 3. This much is a generally conventional form of trip catch switch.

In order to provide for a remotely operable return from the position 1 5 to the position 13, using power which is available in the equipment at the on position, the island 1 2 is provided with a surface 1 7 which is substantially transverse to the direction of axial movement of the slider 2 so that the trip catch 1 5 will have no normal tendency to slide across this service 1 7 from the position 15, but can be slid thereacross without undue effort to a position 1 8 where it will allow the spring to move the slider and the trip catch will return to the position 1 3.

For this purpose, a mild steel frame 19, shown partially cut-away in Fig. 1 is secured in the body 1 and carries a solenoid coil 20 having a core, one end of which is shown at 21 projecting from the coil 20. Power to the coil is fed in via terminals 22 whose supply may be controlled by a relay or other switch controlled by a suitable form of remote control device. An armature for the coil is in the form of a mild steel flap 23 having a first tongue 24 extending through a slot in the frame 1 9.

A steel spring 25 acts as a retainer for the flap 23 and also urges it to a position, as illustrated particularly in Fig. 3, away from the core end 21.

The flap 23 also carries a second tongue 26 which engages in a slot at one end 27 of a lever 28 pivoted at 29 on the body 1 and having a second arm 30 located above the slide 2 in the region of the trip catch 9.

When the coil 20 is energized, the flap 23 is attracted towards the core end 21 to complete the magnetic circuit and this causes the lever 28 to pivot in a counter-clockwise direction as shown in Fig. 2 so that its arm 30 engages the trip catch 9 and sweeps its end from the position 1 5 towards the position 1 8 of Fig. 5 so as to release the slide 2 and cause the switch to be moved to its off position by the spring 3.

Various modifications may be made within the scope of the invention. For instance, the actual mechanism for moving the trip catch may vary to a considerable extent.

Claims

1. A push button electrical switch having a spring loaded slider adapted to be retained selectively in activated and de-activated positions by a trip catch engageable with a cam track traversed by the trip catch as the slider is successively depressed, characterised in that means is provided for displacing the trip catch in the cam track in one of the said positions without depression of the slider so as to release the slider to return to the other position under its spring loading.

2. A push button electrical switch as claimed in claim 1, characterised in that the displacing means operates to displace the trip catch from the activated position.

3. A push button electrical switch as claimed in claim 1 or 2, characterised in that the displacing means is solenoid operated.

4. A push button electrical switch as claimed in claim 2 and 3, characterised in that the solenoid uses power derived from a source controlling by the switch.

5. A push button electrical switch as claimed in claims 1, 2, 3 or 4, characterised in that the displacing means is spring returned.

6. A push button electrical switch as claimed in any of the preceding claims, characterised in that the displacing means comprises a pivotable arm adapted to sweep the trip catch laterally from the said one position.