Field of Invention

The invention belongs to the field of devices intended for electronic surge protection, more precisely to the field of a mechanism that makes it possible to lock a detachable module in a base part of a surge protective device. Technical Problem

The technical problem solved by the present invention is a constructional solution to locking a detachable module, which allows securing the module against falling out from the base part of a surge protective device. The constructional solution must secure the module against falling out or from getting displaced after it has been inserted into the base part. The module may fall out or get displaced due to vibrations during transport or general handling. Mechanical security against falling out must also be operative during a lightning strike, when electromagnetic forces are so high that they cause ejection of the module from the base part.

Prior Art

A solution to mechanical protection of a module is known from patent DE102008017423A1 , wherein the solution is based on an insert having a specific shape and being inserted into a base part of a surge protective device. The insert is pivotably arranged in its seat. When no module is present in the base part, the insert is oriented in a way to allow free insertion of the module into the base part. In order to keep the right position of the module or to lock the module in proper place after it has been inserted, the insert must be rotated in a way that its specific shape due to suitable geometry on the module prevents the module from moving in vertical direction. The insert is rotated by a screwdriver. To release the movement of the module in vertical direction, the same steps are performed in reverse order. The solution from WO2008009507A1 refers to a use of a special wedge-shaped element on the module, wherein flexibility of a plastic material and an inverse shape on the wedge receiving base part are taken advantage of. When the module is inserted into the base part of the surge protective device, the wedge-shaped part automatically retracts to the interior of the module, where space is provided, due to friction and snaps in place immediately when the inverse shape on the base part allows it. The module is thus prevented from getting further displaced in vertical direction. When the plastic part on the module side is pushed, the wedge displaces from the position, in which the inverse shape of the base part is present, thus allowing an unhindered displacement of the module in vertical direction.

Description of the Solution to the Technical Problem The essence of the lock of the detachable module in the base part of the surge protective device of the invention lies in that locking buttons of a symmetrical assembly run along a specially shaped recess while the module is positioned and said buttons engage in the end position with a semi-circular horizontal section. When the buttons are simultaneously moved, the external side of the module indicates the mode »locked« or »unlocked«.

The lock of the detachable module in the base part of the surge protective device of the invention will be described in the continuation by way of figures, representing in: Figure 1 - top view of the module

Figure 2 - lock assembly

Figure 3a - indication of the mode »locked«

Figure 3b - indication of the mode »unlocked«

Figure 4a - base part and module

Figure 4b - detail A

The present solution to the lock of a base part 2 and a module 1 is embodied by a characteristic construction of a lock system in the module 1 and a characteristic retaining shape on receiving walls of the base part 2. A housing 1a of the module 1 is provided at its longer side by a special barrier 1 b having a shorter side wall 1 b' adjacent to an external side wall 1 a'. Into a gap formed by the side walls 1 b and 1 b' there is arranged a plate 3 provided with a circular opening 3a at one side and with an oblong slanting gap 3b at the other side. A spring 6 is arranged between the side wall 1 b' and the plate 3, said spring being fastened at one side to the gap 3b with a button 4' of an actuator 4 provided with an external button 4" arranged into a groove 1 a'" on a side wall 1 a" of the housing 1 a. The spring 6 is fastened at its other side by a button 5' of a slider 5. The side wall 1 c has a mirror image of the previously described assembly.

The base part 2 is provided in its internal part with a characteristic recess 2a whose , upper section 2a' is shaped as the upper part of the letter V having at its bottom an oblong recess 2a" with side walls terminated in a semi-circular manner. When the module 1 is inserted into the base part 2, the external button 4" of the actuator 4 runs along the upper section 2a' of the recess 2a and ends in the semi-circular side wall of the oblong recess 2a". Simultaneously, a button 7' of an actuator 7 runs along a recess at the other side of the base part. When the buttons 4' and 7' are present in the semi-circular section of the recess 2a, the module is locked in the base part, wherein the button 5 and the button 8 at the other side get displaced with the movement of the plate 3 into the position »locked«. Displacement of the module 1 in vertical direction is herewith prevented. The module can be taken out from the base part by pulling the buttons 5 and 8 at the sides of the module in vertical direction. When the module 1 is to be taken out of the base part 2, it is pulled upwards, wherein the plate 3 returns to the initial position by means of the spring 6. The movement of the buttons 5 and 8 is performed in reverse order as in the case of insertion.

The above-described constructional solution to the lock of the detachable module in the base part of the surge protective device solves the problem of an uncontrolled displacement of the module and of mode indication.