The invention relates to an electrical switchgear apparatus comprising a fixed frame and a circuit breaker movable in the fixed frame between a plugged-out position and a plugged-in position, the circuit breaker comprising at least one pair of main contact means at least one of which is movable and can take with respect to the other a closed position corresponding to electrical conduction and an open position corresponding to breaking.
The Patent application FR-A-2,416,575 describes a switchgear apparatus of this type comprising in addition a state indicating device with an input terminal, a first output terminal and operating means designed to electrically connect the input terminal and the first output terminal when the circuit breaker is in an indexed position with respect to the frame--i.e. the plugged-in position--and that the circuit breaker main contacts are in their closed state. The state indicating device comprises a junction unit secured to the frame and a kinematic link with the main contact means of the circuit breaker. The junction unit comprises the input terminal and the output terminal, which are connected as a bridge by a corresponding pair of movable contacts securedly united and connected to one another. According to the position given to the pair of movable contacts, the bridge is conducting or not. The kinematic link comprises a lever pivoting around a spindle secured to the frame of the switchgear, one end of which acts on the pair of movable contacts of the junction unit and the other end of which is shaped as a fork which engages in a crank secured to the main movable contact means of the circuit breaker when the circuit breaker reaches its plugged-in position. When the circuit breaker is not in its plugged-in position, the lever is not biased by the crank and is blocked in a rest position by a slide. When the slide reaches the plugged-in position, it is repelled by a stop securedly affixed to the circuit breaker and releases the lever. The position of the lever is then imposed by that of the crank: if the main contact means are open, the crank is in a position such that the lever remains in its rest position. When the main contact means are reclosed, the crank pivots driving the lever which modifies the position of the pair of movable contacts of the junction unit.
To modify the choice of the indexed position, the size of the lever can be modified in such a way that cooperation with the crank begins earlier, for example in the test position in which the main terminals of the circuit breaker are separated whereas auxiliary terminals of control circuits of the circuit breaker are connected. In this case, the information supplied by the junction unit is different: the bridge is conducting if the Circuit breaker is situated somewhere between its test position and its plugged-in position and if at the same time the main contact means are closed.
The indicating device therefore has limited functions: it is not designed for example to deliver information characteristic of the fact that the circuit breaker is in the test and closed position. Moreover, it is bulky, which limits its use in practice. Indeed, today it is required to be able to meet various user requirements, and in particular to be able to juxtapose different state indicating devices giving different information on the state of the switchgear apparatus: one for example on the fact that the circuit breaker is closed and plugged-in; another on the fact that the circuit breaker is in the test and closed position; another on the fact that the circuit breaker is situated between the plugged-out position and the test and open position. With the device of the prior state of the technique, such a juxtaposition would involve a multiplicity of kinematic links, and therefore levers of large dimensions. Such a device would be too bulky, too fragile and too costly. Furthermore, the device described up to now does not enable the state indicating device to be positioned with sufficient freedom with respect to the frame. However all the auxiliary contacts of a frame, of which the indicating device is a part, are now required to be disposed on a single terminal block, which in practice imposes positioning constraints incompatible with the architecture described.