Improvements in and relating to circuit breakers

Abstract: The invention relates to circuit breakers and to adapters for circuit breakers, more particularly, although not exclusively, to miniature circuit breakers. This adapter comprises an electrically conductive member formed to be attachable to a circuit breaker, having a portion (12) to be clamped and electrically connectable within a cable entry of the circuit breaker, a downwardly dependable connection portion (13a), and an upwardly dependable support portion (13a, 13b) for engagement with the circuit breaker casing, in use.

Description: The invention relates to adapters for circuit breakers, more particularly, although not exclusively, to miniature circuit breakers (m.c.b's). The invention further relates to an adapter and circuit breaker in combination. Standard m.c.b's at the present have screw terminals for both the incoming and outgoing electrical connections. However, load centres and consumer units for example as disclosed in European Patent no 0,325,370, have provisions for m.c.b's to plug onto bus bars to provide the incoming electrical connection thereto. United Kingdom patent application no 2301940A discloses a simple and inexpensive adapter for converting standard m.c.b' s for plug on or plug in usage. It is an object of the present invention to provide such an adapter which has an improved location and support arrangement and is simple and inexpensive to manufacture. According to one aspect of the invention there is provided an adapter which comprises an electrically conductive member formed to be attachable to a circuit breaker of a type having a casing and a cable entry formed in an end wall of the casing, the electrically conductive member comprising: a central body portion; a first part extending from said body portion to be clamped and electrically connected within the cable entry of the circuit breaker; a second part including an electrical connector portion and extending from the body portion in a direction substantially normal to said first part; and a third part including a support portion extending from said body portion in a direction opposite to the second part and adapted to extend in use along the end wall of the circuit breaker casing and to engage the casing so as to provide mechanical support. The adapter may be formed from a blank of electrically conductive material. The blank may comprise a generally sheet-form member having: a portion to form said central body portion; a first portion extending coplanar with said central body portion and which can be bent to lie normal to said body portion to form said first part to be clamped and electrically connectable within a cable entry of the circuit breaker; first and second wing portions extending from opposite sides of said central body portion and each being bendable in a direction opposite to said first portion to lie in a respective plane normal to both said body portion and said first portion; wherein each wing portion includes first and second arms extending in opposite directions away from said body portion, wherein the first arms of said wing portions form said support portion and the second arms of said wing portions can be further arcuately bent to form said connector portion. Parts of the first arms distal to said central body portion may be formed with a nose portion for engagement with the circuit breaker casing, in use. The adapter may be provided in combination with an electrically insulative cover member engageable with the casing of the circuit breaker and adapted to cover the adapter when said first part is clamped in said cable entry. Said first part may join said body portion at the same end as the third part, opposite to the end to which the second part joins the body portion. The invention in a second aspect provides an adapter according the first aspect of the invention as set forth above, in combination with a circuit breaker of the type described. The foregoing and further features of the invention may be more readily understood from the following description of a preferred embodiment thereof by way example, with reference to the 5 accompanying drawing, in which:- Fig 1 shows a plan view of a blank for forming an adapter; Fig.2 shows a front elevational view of an adapter formed from the blank of Fig.1; Fig.3 shows a side elevational view of the adapter of Fig.2; Fig.4 shows a plan view of the adapter of Figs 2 and 3, and Fig.5 is an exploded perspective view of an adapter of Figs 1 to 4 on reduced scale attachment to a circuit breaker. Referring now to Fig.1 of the drawing there is shown a blank 10 for a circuit breaker adapter. The blank 10 comprises a generally sheet - form member with a central body portion 11, an upwardly extending portion 12 and two wing portions 13 extending upwardly and downwardly from opposed sides of the body portion 11. Referring now also to Figs 2,3 and 4 of the drawings portion 12 of the blank is bent upwardly from body portion 11 to lie in a plane normal to the plane of body portion 11. The two wing portions 13 are bent downwardly from body portion 11 to lie in coplanar relationship normal to the plane of body portion 11. The upper arms 13a of wing 13 are each formed with a nose portion 13b extending in the direction of portion 12. The lower leg portions 13c of wings 13 are bent in arcuate fashion adjacent extremities 13d to provide plug on contacts. Referring now to Fig.5 of the drawing there is shown an exploded perspective view of an m.c.b. 14 an adapter and an electrically insulative cover 15. The adapter is located with portion 12 inserted into the cable entry of m.c.b. 14 with arms 13a and nose portion 13b abutting the edge of m.c.b. 14 and legs portions 13c depending downwardly therefrom. The cover 15 is located over the edge of m.c.b. 14 to cover the adapter and cable entry. The provision of the arm and nose portions 13a 13b provide a more rigid connection of the adapter to an m.c.b. and formation of the adapter from blank provides a simple and inexpensive form of manufacture.

Claims: An adapter which comprises an electrically conductive member formed to be attachable to a circuit breaker of a type having a casing and a cable entry formed in an end wall of the casing, the electrically conductive member comprising: a central body portion; a first part extending from said body portion to be clamped and electrically connected within the cable entry of the circuit breaker; a second part including an electrical connector portion and extending from the body portion in a direction substantially normal to said first part; and a third part including a support portion extending from said body portion in a direction opposite to the second part and adapted to extend in use along the end wall of the circuit breaker casing and to engage the casing so as to provide mechanical support. An adapter as claimed in claim 1 formed from a blank of electrically conductive material. An adapter as claimed in claim 2 wherein said blank comprises a generally sheet-form member having: a portion to form said central body portion; a first portion extending coplanar with said central body portion and which can be bent to lie normal to said body portion to form said first part to be clamped and electrically connectable within a cable entry of the circuit breaker; first and second wing portions extending from opposite sides of said central body portion and each being bendable in a direction opposite to said first portion to lie in a respective plane normal to both said body portion and said first portion; wherein each wing portion includes first and second arms extending in opposite directions away from said body portion, wherein the first arms of said wing portions form said support portion and the second arms of said wing portions can be further arcuately bent to form said connector portion. An adapter as claimed in claim 3 wherein parts of the first arms distal to said central body portion are each formed with a nose portion for engagement with the circuit breaker casing, in use. An adapter as claimed in any preceding claim in combination with an electrically insulative cover member engageable with the casing of the circuit breaker and adapted to cover the adapter when said first part is clamped in said cable entry. An adapter as claimed in any preceding claim wherein said first part joins said body portion at the same end as the third part, opposite to the end to which the second part joins the body portion. An adapter as claimed in any preceding claim in combination with said circuit breaker.

Inventors: BAKER ANDREW PURDIE, BALL KEITH WRAY, COLE ANTHONY ROBERT, BAKER, ANDREW PURDIE, BALL, KEITH WRAY, COLE, ANTHONY ROBERT
Applicants: SCHNEIDER ELECTRIC IND SAS, SCHNEIDER ELECTRIC INDUSTRIES SAS
Application year: 1998
Main classification: H01H71
IPC codes: H01H71, H01H11, H01H9