High-security quick-release fastener

Abstract

A device forming a coupler including a coupler, or quick-release fastener, and a connection device; the connection device including at least one, preferably two, trunnions, front and back respectively; the coupler including a base body from which, on a front side, at least one hook originates having a region forming a rod and a region forming a hook head extending upwards from the region forming a rod to form, with the base body, at least one receiving cavity for the trunnion or trunnions, having an opening at the top extending between the base body and the region forming the respective head of the respective hook. When the trunnion or trunnions in the receiving cavity comes into contact with the region forming a rod, the region forming a head extends upwards beyond the centre of the circular section of the trunnion.

1 . A device forming a coupler comprising a coupler ( 1 ), or quick-release fastener, which is intended to be attached to a construction machine, such as a mechanical shovel, and a connection device ( 2 ), which is intended to be attached to a tool such as a bucket;
 the connection device comprising at least one trunnion ( 5 ;  6 ;  5 ,  6 ), preferably two trunnions ( 5 ,  6 );   the coupler comprising a base body from which, on a front side, at least one hook originates, the or each hook ( 7 ) having a part forming a rod and a part ( 72 ) forming a hook head, which extends upwards from the part forming a rod to define at least one receiving cavity ( 200 ) for the trunnion or one of the trunnions, having an opening ( 201 ) at the top which extends between the base body and the part forming the respective head of the respective hook:   characterised in that, when the trunnion or one of the trunnions in the receiving cavity comes into contact with the part forming a rod, the part forming a head extends upwards beyond the centre of the circular section of the trunnion, the or each receiving cavity comprising, on the rear side, a recessed area created in the base body in which the trunnion can penetrate at least in part, the or each hook ( 7 ) not being mobile in relation to the base body.   
     
     
         2 . The device according to  claim 1 , characterised in that the part forming the head extends upwards beyond the trunnion. 
     
     
         3 . The device according to  claim 1 , characterised in that the recessed area has a shape that, in longitudinal section, complements substantially at least half of the circular section of the trunnion. 
     
     
         4 . The device according to  claim 1 , characterised in that the connection device ( 2 ) comprises a lower base plate and on the upper side two lateral flanks, two trunnions spaced apart from one another being attached to the two flanks so as to extend between them, at a distance from the base plate, to allow the or each front hook of the quick-release fastener to pass between them and the base plate. 
     
     
         5 . The device according to  claim 1 , characterised in that the coupler ( 1 ) or quick-release fastener, comprises an upper base plate ( 101 ) from which two lateral flanks ( 102 ) protrude downwards, each flank ( 102 ) terminating on the front side in a respective hook ( 7 ). 
     
     
         6 . The device according to  claim 1 , characterised in that, in longitudinal section, the highest point of the part forming the hook head is beyond the trunnion when said trunnion is located in the cavity, in contact with the part forming a rod. 
     
     
         7 . The device according to  claim 1 , characterised in that, in longitudinal section, the highest point of the inner wall of the part of the cavity formed by the part forming the hook head is beyond the centre of the trunnion section, and in particular substantially at a level between the radius and diameter of the trunnion section. 
     
     
         8 . The device according to  claim 1 , characterised in that the connection device comprises two trunnions and, in the base body of the coupler, at least one second rear cavity for receiving the trunnion is defined, intended to receive the other trunnion once the first trunnion is attached to the hook or to each hook, said second rear cavity being open at the bottom, i.e. in the opposite direction to the direction towards which the opening of the first front receiving cavity faces. 
     
     
         9 . A quick-release fastener forming part of a device according to  claim 1 .