GB2041662A

GB2041662A - Improvements in or relating to lampholders

Info

Publication number: GB2041662A
Application number: GB7903838A
Authority: GB
Original assignee: CHING MEI ELECTRIC MANUFACTURI
Current assignee: CHING MEI ELECTRIC MANUFACTURI
Priority date: 1979-02-02
Filing date: 1979-02-02
Publication date: 1980-09-10

Abstract

A lampholder comprises a body 1, 2 and an on-off switch 5, 14, 21-25 disposed between a first pair of terminals 3 for connection to electrical conductors for supplying power and a second pair of terminals 12 for connection to terminals of a lamp. The on-off switch 5, 14, 21-25 is substantially completely enclosed by the body 1, 2 and may include a straight push-bar 21 for actuation thereof. The push-bar 20 has a transverse portion 22 having conductive studs 25 therein which receive an end of respective springs 14 each biassing a terminal 12. A projection 26 on portion 22 cooperates with a spring metal member 27 to provide a toggle action. <IMAGE>

Description

SPECIFICATION Improvements in or relating to lampholders The present invention relates to lampholders, for instance for use in table lamps or standard lamps or for suspension from cables or flex supplying power thereto.

According to the invention, there is provided a lampholder comprising a body and an on-off switch disposed between a first pair of terminals for connection to electrical conductors for supplying power and a second pair of terminals for connection to terminals on a lamp, the on-off switch being substantially completely enclosed by the body.

Preferably, the on-off switch includes a straight push-bar for actuation thereof.

Preferably, the body is made of plastics material.

Preferably, the terminals of the second pair are movable and urged outwardly of the body by electrically conductive springs which, with the on-off switch in the on position, connect together electrically respective ones of the first pair of terminals and the second pair of terminals.

Preferably, the push-bar includes at least one conductive stud in which the end of a corresponding one of the springs distant from the corresponding one of the second terminals engages, the conductive stud contacting the corresponding one of the first terminals with the push-bar in the on position and being out of contact therewith with the push-bar in the off position.

The invention will be further described, by way of example, with reference to the accompanying drawing, in which: Figure 1 is a cross-sectional view of a preferred lampholder; Figure 2 is a view from below of the lampholder of Figure 1; Figure 3 is a plan view of the lampholder of Figure 1 with a cover thereof removed; Figure 4 is a plan view of a push-bar of the lampholder of Figure 1; Figure 5 is a cross-sectional view on the line V-V of Figure 4; Figure 6 is a cross-sectional view of part of the lampholder of Figure 1 with an on-offswitchthereof in the off position; and Figure 7 is a cross-sectional view of part of the lampholder of Figure 1 with the switch in the on position.

With reference to the accompanying drawings, the preferred lampholder comprises a body formed in two parts 1 and 2 held together by a pair of bolts (not shown). The part 2 of the body carries on an end thereof a first pair of terminals 3 provided with screws 4for clamping electrical conductors in holes formed in the terminals 3. The terminals 3 are secured to the end of the part 2 of the body by means of electrically conductive extensions in the form of rivets 5 which pass through holes in the end of the part 2. There is also provided on the end of the part 2 between the terminals 3 a cable clamp 6 in the form of a generally hook-shaped projection formed on the part 2. The part 2 is provided with a screw thread 7 on which is screwed a cover 8 having formed therein a hole 9 to allow passage into the lampholder of electrical conductors for supplying power to a lamp.

The cover 8 is also provided with a recessed portion having a screw thread 10 to allow the lampholder to be mounted on, for instance, the base of a table or standard lamp.

The part 1 of the body has formed therein two bores 11 in which are mounted a second pair of elongate terminals 12 for movement parallel to their axes. Shoulders 13 provided by the part 1 of the body prevent the terminals 12 from falling out of the body, while a pair of electrically conductive springs 14 urge the terminals 13 outwardly of the body.

The part 1 has a generally annular extension 15 in which are formed a pair of L-shaped holes 16 extending away from the end of the part 1 distant from the part 2. Each of the holes 16 has an edge defined by a portion 17 so as to allow the lampholder to function as a bayonet lock with a lamp provided with corresponding studs. The part 1 has formed thereon a screw thread 18 on which is mounted a sleeve 19.

Between the first pair of terminals 3 and the second pair of terminals 12, there is provided a push-bar 20 having an elongate straight portion 21 and a transverse portion 22. The straight portion 21 extends through holes 23 formed in the part 2 of the body and is slidable between a first position and a second position, the push-bar forming part of an on-off switch which, in Figure 6 is shown in the off position and, in Figure 7, is shown in the on position, and which is substantially completely enclosed by the body. The transverse portion 22 has formed therein a pair of holes 24 which accommodate conductive studs 25. The ends of the springs 14 distant from the second pair of terminals 12 are retained in the studs 25 and urge the studs towards the rivets 5.

The transverse portion 22 has formed at its middle part a projection 26. The projection 26 cooperates with a bent piece of springy metal 27 to provide a toggle action for the on-off switch of the lampholder whereby the push-bar 20 is urged into one of two stable positions corresponding to an on position and an off position.

Figure 6 shows the switch mechanism in the off position in which the push-bar is retained at its right-most position by the springy piece of metal 27 with the studs 25 being urged by the springs 14 into a channel 28 formed in the part 2 of the body. When the push-bar 20 is pressed to the left, the springy piece of metal 27 provides a toggle action which eventually holds the push-bar over at its left-most position, as shown in Figure 7. In this positiOn, the studs 25 mounted in the transverse portion 22 contact respective rivets 5 of the terminals 3 so that a conductive path is provided by each spring 14 between respective ones of the first pair of terminals 3 and the second pair of terminals 12. Thus, power supplied via conductors when connected to the first pair of terminals 3 is supplied to a lamp via the second pair of terminals 12 when a lamp is held by the lampholder.

Claims

1. A lampholder comprising a body and an on-off

switch disposed between a first pair of terminals for connection to electrical conductors for supplying power and a second pair of terminals for connection to terminals on a lamp, the on-off switch being substantially completely enclosed by the body.

2. A lampholder as claimed in claim 1, in which the on-off switch includes a straight push-bar for actuation thereof.

3. A lampholder as claimed in claim 1 or 2, in which the body is made of plastic material.

4. A lampholder as claimed in any one of the preceding claims, in which the terminals of the second pair are movable and urged outwardly of the body by electrically conductive springs which, with the on-off switch in the on position, connect together electrically respective ones of the first pair of terminals and the second pair of terminals.

5. A lampholder as claimed in any one of the preceding claims, in which the push-bar includes at least one conductive stud in which the end of a corresponding one of the springs distant from the corresponding one of the second terminals engages, the conductive stud contacting the corresponding one of the first terminals with the push-bar in the on position and being out of contact therewith with the push-bar in the off position.

6. A lampholder substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.