IE80609B1

IE80609B1 - Improvements in and relating to circuit breakers

Info

Publication number: IE80609B1
Application number: IE940049A
Authority: IE
Inventors: Desmond Regan; Shay Lavelle; Thomas O'carroll
Original assignee: Square D Co
Priority date: 1994-01-21
Filing date: 1994-01-21
Publication date: 1998-10-21
Also published as: GB2285890A; IE940049A1; GB2285890B; GB9419931D0

Abstract

A handle interlock 1 for interlocking the handle 4 of a circuit breaker with the operating handle 4 of an adjacent circuit breaker or auxiliary device comprises a central handle portion 10 and a pair of spigots 11, one on either side of the handle portion 10. Each of the spigots 11 includes a tapered lead-in portion 12 for engagement of the spigot 11 in an engagement socket 5 of an operating handle 4. The spigots 11 include alternating steps and grooves 11a, 11b for non-rotatable engagement with complementary steps and grooves 5a, 5b of the socket of the operating handle 4. By virtue of the handle interlock 1, all of the handles 4 operate substantially simultaneously.

Description

“IMPROVEMENTS IN AND RELATING TO CIRCUIT BREAKERS” The invention relates to improvements in and relating to multipole circuit breakers and in particular to a handle interlock for a circuit breaker and another circuit breaker or an ancillary or auxiliary device each having separate handles and each handle having an interlock engagement socket.

It is well known to provide a circuit breaker for each phase of an electrical supply and to interlink the circuit breakers by means of handle interlock devices to provide a multipole circuit breaker. In most cases the handle interlock devices are inserted on assembly of the multipole circuit breaker in a factory. In other cases the handle interlock is fitted on site, particularly when a circuit breaker is to be coupled to an ancillary or auxiliary device such as a command, control or indicating device. In either case however with existing handle interlock devices there is a risk that the circuit breaker or breakers and/or auxiliary devices may not operate simultaneously.

This invention is directed towards providing an improved interlock for a circuit breaker which will overcome this difficulty.

The invention is characterised in that the handle interlock comprises a handle portion and a pair of projecting spigots, one on either side of the handle portion, for non-rotatable engagement with engagement sockets of adjacent operating handles so that the interlinked operating handles move substantially simultaneously on operation of at least one operating handle wherein each spigot includes alternating steps and grooves for non-rotatable engagement with complementary steps and grooves of the engagement socket.

In a particularly preferred embodiment of the invention, the handle portion is aligned in use with and is contoured to substantially follow the shape of an -2operating handle. This has the advantage of allowing the operating handle and/or portion of the interlock to be presented in the same way to an operator, thus improving the operation of the handles of the multipole circuit breaker.

In a particularly preferred embodiment of the invention each spigot includes a lead-in tapered portion for engagement of the spigot in the engagement socket of an operating handle. This feature is particularly important in allowing an extremely tight interference fit to be achieved between the handle interlock and the associated operating handles. This is important in ensuring non-rotatable interengagement between the interlock and the adjacent operating handles. In this way the simultaneous operation of the interlinked operating handles is assured.

The invention also provides a multipole circuit breaker comprising a circuit breaker and another circuit breaker or auxiliary device, each having separate operating handles and each provided with an interlock engagement socket and a handle interlock according to the invention extending therebetween.

The invention will be more clearly understood from the following description thereof, given by way of example only with reference to the accompanying drawings in which:Fig. 1 is an exploded perspective view of a handle interlock according to the invention with two associated operating handles; Fig. 2 is an exploded perspective view of the handle interlock with one associated operating handle; Fig. 3 is a perspective view similar to Fig. 2 with the handle interlock in position; -3Fig. 4 is a perspective view of a handle interlock in position in two adjacent operating handles; and Fig. 5 is a perspective view of a multipole circuit breaker incorporating a handle interlock according to the invention.

Referring to the drawings there is illustrated a handle interlock according to the invention indicated generally by the reference numeral 1 for a circuit breaker such as a circuit breaker 2 illustrated in Fig. 5. The circuit breaker 2 is of the type comprising at least two individual circuit breakers 3, each having separate operating handles 4. Alternatively or additionally, an auxiliary device may be mounted to the circuit breaker. Each operating handle 4 has an interlock engagement socket 5 at each end which may extend through the handle 4.

In more detail, the handle interlock 1 comprises a central handle portion 10 and a pair of spigots 11, one on either side of the handle portion 10, for non-rotatable engagement with the engagement sockets 5 of adjacent operating handles 4. Each of the spigots 11 includes a tapered lead-in portion 12 for engagement of the spigot 11 in the engagement socket 5 of the operating handle 4. Each spigot 11 includes alternating steps and grooves 11a, lib for engagement with complementary steps and grooves 5a, 5b of the socket 5 of the operating handle 4.

The handle portion 10 of the interlock 1 is aligned in use and is contoured to substantially follow the shape of the operating handles 4 of the adjacent circuit breakers in a multipole circuit breaker device. This ensures that the handle interlock is blended with and essentially forms an integral part of the adjacent operating handles 4. A user recognises no difference in operation between the handle 4 and interlock 1 so that regardless of which part of the integral operating handles and interlocks of the multipole circuit breaker that a user operates, because the spigots 11 are non-rotatably engaged in the sockets 5 of the operating handles 4, all of the handles will operate substantially simultaneously ensuring -4that all phases of the electrical supply are turned off at the same time. Thus, the action of one operating handle 4 results in simultaneous operation of all of the ’ handles 4. The same interlock component 1 may be used for all multipole devices with or without auxiliary devices regardless of the number of poles involved. t In addition, the handle interlock 1 acts as a spacer between adjacent operating handles and because the interlock 1 may have the same profile as the adjacent operating handles 4, it camouflages the gap between the handles. The handle interlock 1 according to the invention is essentially an integral mating component rather than a link pin or spacer.

Many variations on the specific embodiments of the invention described will be readily apparent and accordingly the invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail.

Claims

1. A handle interlock for coupling a circuit breaker of the type having an operating handle to another circuit breaker or ancillary device having an operating handle, each operating handle having an interlock engagement socket, the handle interlock comprising a handle portion and a pair of projecting spigots, one on either side of the handle portion, for nonrotatable engagement with engagement sockets of adjacent operating handles so that the interlinked operating handles move substantially simultaneously on operation of at least one operating handle, wherein each spigot includes alternating steps and grooves for non-rotatable engagement with complementary steps and grooves of the engagement socket.

2. A handle interlock as claimed in claim 1 wherein the handle portion is aligned in use with and is contoured to substantially follow the shape of an operating handle.

3. A handle interlock as claimed in claim 1 or 2 wherein each spigot includes a lead-in tapered portion for engagement of the spigot in the engagement socket of an operating handle.

4. A handle interlock substantially as hereinbefore described with reference to the accompanying drawings.

5. A circuit breaker comprising a circuit breaker and another circuit breaker or auxiliary device, each having separate operating handles and each provided with an interlock engagement socket and a handle interlock as claimed in any preceding claim extending therebetween.

6. A circuit breaker substantially as hereinbefore described with reference to the accompanying drawings.