Magnetically Actuated Illuminating Warning Device for Circuit Breakers

1. Field of the Invention

The present invention relates to overload circuit indicators for circuit breakers, and more particularly, to such indicators that are magnetically activated and battery powered.

2. Description of the Prior Art

The need for an illuminated indicator for circuit breakers is quite obvious and it has been documented in several U.S. and foreign patents. In particular, one of the present inventors attempted to solve the problem in U.S. Pat. No. 4,056,816 and the above referenced parent application followed after numerous problems with safety testing agencies (UL, CSA, etc.) because the patented device borrows electricity from the very same source that is being regulated. The device disclosed in the parent application does not take any electricity from the source being regulated but rather it is battery powered and designed to be easily adapted to conventional circuit breakers. The invention in the parent application, however, is susceptible to wear and tear and, more important, it can not be used in flammable atmospheres because the electric contacts activated by the switch lever are exposed. The present invention provides for a device that solves the problem outlined, is more reliable and can be safely operated inside spaces with flammable atmospheres.

Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention.

It is the main object of the present invention to provide a magnetically actuated illuminated device warning for circuit breakers that can be readily installed to existing circuit breakers installations.

It is another object of the present invention to provide such a warning device that is self-powered and does not take any electricity from the source being regulated.

It is yet another object of the present invention to provide such a device that is inexpensive to manufacture and maintain while retaining its effectiveness.

Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.

With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which:

FIG. 1 represents a front view of a conventional circuit breaker including the present invention.

FIG. 2 shows a side view of the breaker represented in FIG. 1.

FIG. 3 is a schematic representation of the circuit of the warning device with the magnetic switch and battery.

Referring now to FIGS. 1 and 2, where the improved circuit breaker is generally referred to with numeral 10, it can be observed that it corresponds to a conventional circuit breaker with the addition of illuminated warning device assembly 20, magnetic switch assembly 30 and permanent magnet assembly 40.

Circuit breaker 10 has internally the commonly known mechanism that provides three possible positions for lever 18, namely, ON, OFF and tripped, as illustrated in FIG. 2. Reset 15 brings circuit breaker 10 back to the OFF position from the tripped position.

Illuminated warning device assembly 20 is schematically represented in FIG. 3 and it includes battery element 24, LED element 22 and current limiting resistor 26, all connected in series with magnetic switch assembly 30. Magnetic switch assembly 30 is similar to the ones used for home security alarms to secure openings against intruders. Basically, when a dwelling opening is forced open, the magnetic switch is activated. Switch assembly 30 is normally open and the circuit is closed when permanent magnet assembly 40 comes within a predetermined close distance of switch assembly 30. This causes the switch leaves of assembly 30 to come in contact with each other. Magnetic assembly 40, in the preferred embodiment, consists of magnetic element 45 and sleeve 12 that secures element 45 in position on top of lever 18. The relative position of permanent magnet assembly 40 and switch assembly 30 thus becomes critical and it is to be selected so that switch assembly 30 can only be activated when lever 18 is in the middle which corresponds to the tripped or overload position. The strength of magnetic element 45 is also a factor to be taken into consideration together with the relative position of assembly 30 with respect to assembly 40. Permanent magnet element 45 may be mounted on lever 18 by using a tight bag or sleeve 12, as in the preferred embodiment, or glued to lever 18 or it may be integrally built within lever 18 or lever 18 itself may be magnetized. The last option, of course, being open only to newly manufactured circuit breakers incorporating the present invention. Existing installations will need to mount the present invention to lever 18 and place illuminating warning assembly on a conspicuous place, preferably on the front plate 11 of breaker 10. Button 15 is the conventional reset button found in breakers 10.

It is believed the foregoing description conveys the best understanding of the objects and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense, except as set forth in the following appended claims.