FR2758410A1 - Ejector mechanism for overvoltage or lightning protection adaptor - Google Patents

Abstract

The ejector has a cylindrical chamber (9) in which lies a cylindrical concave piston (1). The piston stem passes through a collar (3) at the head of the chamber where it is soldered (8) to copper braid wiring (2) thereby compressing a helical spring (8). At the end of the life of a varistor or gas discharger in a protection circuit, an excessive current flows to earth. The current melts the solder and releases the piston which is unable to return because of an elbowed sprung strip riveted to the chamber wall to prevent reconnection. Alternatively, a deformed concave washer or turn of a spring may be used to prevent resetting.

Description

 The present invention relates to an arrester and surge arrester adapter ejection device connected to a wall outlet or modular support when these are at the end of their life.

 Protection is currently achieved by devices which short circuit the supply conductors to earth.

 After several operations of the current devices, the varistors or the gas sparklers contained therein allow excessive current to flow, causing the tripping of the supply circuit breaker. The installation is in permanent fault preventing any resetting of the circuit breaker. Some manufacturers provide a cut-off device upstream of the surge arrester allowing the system to be re-energized in order to change it. In these wall or modular systems the user must call in a professional to identify the faults and his installation remains unusable for an indefinite period. Each resetting of the circuit breaker also leads to energizing of the accessible earths of the installation with a possible risk of indirect contact.

 The device according to the invention overcomes this drawback because it in fact has the particularity of separating the surge arrester or surge protector from the wall base or modular support when the protective components are at the end of vic.

 This device is integrated into the two-pole male sector plug plus earth, in which a cylindrical chamber is arranged intended to receive the male earth pin from the wall or modular socket. In this chamber is housed an ejector assembly composed of a cylindrical insulating part which is in abutment against the ground pin and crimped on a copper braid passing through a helical spring. The braid and the pusher compresses the helical spring against the wall of the chamber opposite the ground pin. The braid passing through an orifice at the end of the chamber is kept stretched through a metal flange positioned on the external body of the chamber in the axis of the orifice of the earth pin by means of a weld. This fuse-forming weld therefore maintains only the spring in compression.

 At the end of the life of the varistors or the gas spark gaps contained in the arrester, these allow excessive current to pass to the ground. The resulting instantaneous high energy heating melts the solder and releases the braid.

The spring relaxes and the insulating part, pressing on the earth pin, ejects the adapter from the wall or modular socket completely separating it from the network. The insulating part is locked in the extended position by a bent spring leaf, riveted on the chamber thus preventing the user from reconnecting the adapter.

 The invention and an embodiment will be better understood on reading the description below and on examining the appended figures which accompany it, illustrating: FIG. 1 comprises 2 sectional views of the system ejector fit into a plastic case of a surge arrester or surge protector whose housing of the ejector plug is provided for this purpose.

FIG. 2 represents a view of the ejector system according to FIG. I installed in a wall outlet before the system is triggered. FIG. 3 represents a view of the ejector system according to FIG. 1 having undergone an overvoltage and being ejected from the wall outlet, 4 shows a sectional view of the ejector alone before triggering the system, FIG. 5 represents a sectional view of the ejector alone after triggering of the system due to an overvoltage.

 With reference to these drawings, as can be seen in FIG. 1, the ejector plug device 1) is embedded inside a lightning or surge arrester adapter box (10) in a female housing (14) provided for this purpose. effect. The ejector plug is fitted with two male phase and neutral sector pins (5) and an earth input comprising two spacers (6) establishing contact.

 As seen in Figure 4 the ejection system is composed of a cylindrical chamber (9) in which is located on the sector side a cylindrical and concave pusher (1). Inside it is a crimped copper braid (2) passing through a helical spring (4). The braid (2) and the pusher (1) compresses the coil spring (4) against the wall of the chamber (9) in the axis of the coil spring (4). The braid (2) passing through an orifice at the end of the chamber (9) is held taut through a metal collar (3) located outside in the axis of the orifice of the wall by means of 'a weld (8). This weld (8) forming a fuse therefore maintains the helical spring (4) in compression.

 At the end of the life of the components contained in the surge arrester or surge arrester, these allow excessive current to flow, causing the solder (8) to melt and release the braid (2). Under this action the hecoidal spring (4) relaxes by pressing on the pusher (1). The latter is locked in the extended position by a bent spring leaf (7), riveted on the body of the chamber (9) as can be seen better in FIG. 5.

 To understand this system well, FIG. 2 represents the device before tripping of the ejector plug connected to the socket (12) and FIG. 3 represents this same device after tripping of the ejector plug which comes to bear on the pin (13) and ejects the adapter from the wall or modular outlet.

 According to a variant not illustrated, the non-return blade (7) can be replaced by a deformed concave washer or by a deformed turn of the spring.

 According to a variant not illustrated, the ejection device can be incorporated into the plug of the power cord of existing devices.

 The ejector plug device according to the invention is particularly intended for ejecting adapters or modular assemblies relating to surge arresters or surge protectors.

Claims (3)

 REVEN DICA'I'IONS  1) Arrester and surge arrester ejection device characterized in that it comprises an ejector consisting of a chamber (9) containing a pusher (1) integral with a braid (2) now compressing a spring (4) which will be released during an overvoltage by the fusion of a weld (8) causing the ejection of the defective element by pressing the pusher (1) on the supply base (12).  2) Device according to claim 1 characterized in that it comprises  a leaf spring (7) locking the pusher (1) in the extended position and preventing the  re-energizing the defective element in the power supply base (12).  3) Device according to claim 1 or 2 integrated into a modular arrester  of the table and allowing disconnection to earth.