FR2691574A1 - Electrical contact device for high intensity direct current circuit - has two sacrificial contacts on elastic strips which maintain button contacts until after principal double contacts separate - Google Patents

Abstract

The device includes principal contacts (1) which have a contact zone of lowest possible resistance, and are held together by the movement of an insulating block (9) acting through guide rods (3) and compression springs (4). The block moves to separate the principal contacts while each sacrificial contact (5) is closed by a single leaf spring (8) acting on the connecting strip (7). The sacrificial contact is broken when there is no risk of breakdown except at the sacrificial contacts which are damage resistant and replaceable. The sacrificial contacts are self-clearing by relative displacement. The fixed contacts (2,11) may be welded in bimetallic material to allow different materials to connect the contacts. USE/ADVANTAGE - Electrolysis chambers, assay stations, using 2 to 5000 Amperes. Mechanically simple with small size (15cm x 5cm x 3cm).

Description

The present invention relates to a double electrical contact device with integrated breaking system for "high intensity" electrical circuits.

Traditionally, these circuits are opened and closed using articulated contacts or double contacts with sequential opening. The contact opening last is the "sacrificial" contact. It is equipped with arc-resistant materials, to the detriment of its conductivity.

For such a system to be effective, a large number of sacrificial contacts are required, which increases the bulk and the mechanical complexity.

The device according to the invention overcomes this drawback.

 In fact, according to a first characteristic, it comprises a sacrificial system directly adapted to each of the ends of the double contact.

This "sacrificial" system, due to its elasticity, keeps the current flowing during the start of the opening of the main contact. It then receives all the intensity as well as the manifestations of arc.

The opening continues until a sufficient isolation distance is obtained to stop any flow of current.

According to particular embodiments.

* The connection of the sacrificial system on the main contact can be
produced by a conductive leaf spring.

* An additional spring can be added to strengthen the pres
contact information.

* The flexible connection system of the sacrificial contact can be
inclined to cause relative sliding of the contacts when
pressurization and thus obtain a self-cleaning.

* The contact keys (5-6) can be interchangeable, whether the
system either open or closed, power off or on.

* Fixed contacts (2/11) can be made of materials
bimetallic for example welded by explosion to allow the
connection of the contact system by welding to the main circuit
cipal with different materials.

All the contacts can be secured to an insulating beam
guided, animated by a translational movement causing their
opening and closing.

* The contacts can be kept pressed by their spring on the
insulating beam to reduce their travel relative to this
beam and increase the isolation distance.

* The insulating beam (9) can constitute an insulating barrier during
opening of contacts preventing the establishment of a court
circuit with a metallic object.

The accompanying drawings illustrating the invention.

Figures 1 to 3 show in section the device according to the invention in the three main states: open, being closed, closed.

FIG. 4 represents the association of several devices according to the invention.

With reference to these drawings, the device comprises a double contact (1) made of conductive metal, each of the contact zones of which is provided with pads having the lowest possible contact resistance.

The translation of the insulating beam (9) allows, by means of guide rods (3) and springs (4) to pressurize the contacts and maintain it.

When opening the beam (9) pushes the contact (1) while the sacrifice systems (5) maintain pressure by their flexible conductor (7) and their spring (8) until the pellets (10 ) are far enough apart to avoid any risk of priming.

Arc manifestations are limited to interchangeable pads (5) and (6).

The total opening is adapted to the desired level of insulation.

When closing, the beam (9) pulls the contact (1) by the intervention of the springs (2) and the guide rods (3).

The sacrificial contacts touch the fixed parts with a relative movement of self-cleaning. Then the pellets (10) come into contact with a rapid increase in pressure until the beam is stabilized, leaving a clearance under the contacts. Any geometric deviations are compensated for by the springs (4).

According to a variant not illustrated, the insulating beam (9) can be driven in a translational movement perpendicular to the closure of the contacts in order to create a self-cleaning of the pellets (10).

According to a variant not illustrated, the opening mechanism could be surrounded by a sealed envelope allowing operation under vacuum or under inert gas.

By way of nonlimiting example, the contact (1) will have dimensions of the order of 15 cm for the length, 3 cm for the width and 5 cm for the height with a current flowing therefrom from 2 to 5000 amperes.

The device according to the invention is particularly intended for the direct current electrical circuit of electrolysis rooms and test stations.

Claims (6)

1. The double electrical contact device characterized in that it comprises a sacrificial system (5, 7) directly adapted on each of its ends ensuring the protection of its contact pads (10) -when the circuit is opened. 2. Device according to claim 1 characterized in that the flexible connection system (7) of the sacrificial contact (5) on the double contact (1) is inclined. 3. Device according to claim 1 and 2 characterized in that the flexible connection system (7) is electrically conductive. 4. Device according to any one of the preceding claims, characterized in that the sacrificial contact keys (5, 6) are interchangeable. 5. Device according to claim 1 characterized in that the contact is actuated by an insulating beam (9) establishing an insulating barrier between the live parts during opening. 6. Device according to claim 1 characterized in that it comprises fixed parts (2 and 11) made of bimetallic materials adapted to the nature of the circuits to which they are going to be connected.