FR2486134A1 - Plug for retaining key in door lock - comprises resilient bung inserted into key-hole after key bit - Google Patents

Abstract

The plug for retaining a key in a door lock comprises a front face (6) the exterior of which is slightly curved and a resilient rear plug (7) inserted into the key-hole after the key. The rear part (7) is hollow and trapezoidal in cross-section. The inclined side (10) of the trapezoidal rear part (7) is separated from the front part (6) by a gap (12). The external surfaces of the sides (8,10) of the trapezoidal rear part (7) carry anchorage grooves.

Description

 The present invention relates to door locks and their cleanliness plates, it aims to avoid the retcur and the fall of the keys of all locks carrying a cleanliness plate on all door systems.

 Among the proposed devices of this type, there are systems for closing the keyholes, but no anti-return devices for the door key adaptable to all cleaning plates.

 Until now, very often, when opening and closing doors, the keys fall. Falls frequently cause damage to the floor, damaged tiles and parquet and can even lead to the loss of the key.

 The purpose of the intention is to remedy these drawbacks which have just been mentioned above.

 The subject of the invention is a plastic key anti-return part with a polished front face carrying on the back an elastic fixing system.

 The invention may in any case be well understood with the aid of the additional description which follows as well as of the appended drawings, which supplements and drawings relate to a preferred embodiment of the invention and of course do not include any limiting character.

 Figure 1 of these drawings shows a front view of the cleanliness plate 2 having in its key passage orifice a key non-return part, Figure 3-object of the invention.

 2 shows a schematic cross section of Figure 1 along the axis A-A-. It shows a key 3 in its housing 5 in position, it is blocked by the non-return device, Figure 3 - object of the invention.

 Figure 3 is a perspective view of the key non-return part object of the invention.

 Figure 4 shows a section of Figure 3 along the axis B - B.

 Figure 5 is a perspective of a variant of the invention.

 Figure 6 shows a section of a variant of the invention.

 FIG. 7 represents a section of another possible variant of the key non-return part in FIG. 3.

 Figure 1 of these drawings which shows a front view of the cleanliness plate 2 having in its key passage opening 1 a key non-return part shown in Figure 3 object of the invention.

In Figure 2 showing a cross section of Figure I in
AA, a key 3 is shown in its housing 5 in position and blocked by the device of Figure 3 object of the invention.

 This device (Figures 3 and 4) consists of a plate 6 face of cleanliness slightly curved across the width, secured to a part 7 in the shape of a rectangular trapezoid prism (allowing the key to stop and its attachment to the plate of cleanliness) whose large base rests on the face 6. This part 7 is made integral with the plate 6 by the side 8 rigid wall and perpendicular side of the trapezoid. The height of the rib 8 of the rectangular trapezoid defines the key locking clearance in the operating position.

 This trapezoidal part has in its middle a recess 9 which crosses it in the longitudinal direction. The inclined wall 10 of the trapezium is cut at 12 so that its end is separated from the plate 6, by this fact, the wall 10 becomes elastic. The marker 11 represents the cradle for the key rod 3. The walls 8 and 10 are ridged to prevent any slipping.

 Figure 5 is a perspective of a variant of the invention. The cradle 11 is eliminated and the plate 6 lengthened 13 which makes it possible to plug the key passage hole on the cleanliness plate.

 Figure 6 is a section of a variant of the invention with a central support 14 welded by its base to the cleanliness face 6 and carrying 2 inclined elastic lips 15 which thus form a clip-on system anti-key return.

 Figure 7 is a section through another possible variant of the invention.

The rectangular trapezoid prism 16 welded by its large base to the cleanliness face 6. Unlike the other variants, this trapezoid is not hollow,
Massi @ in very elastic material. The sides 17 of the trapezium have small bosses which allow the removable elastic fixing on the key passage hole in the cleanliness plate of a door.

Claims (9)

 1. Key anti-return piece characterized in that it comprises a front plate, slightly curved cleanliness face bearing on its rear part an elastic means fitting into the opening (1) of the cleanliness plate of a door. the  2. key anti-return piece according to claim 1 caraetérisde in that the elastic means consists of a piece in the form of a trapezoidal prism (7) resting on the piece (6) by its large base.  3. key anti-return piece according to claims 1 and 2 characterized in that the trapezoidal part has a recess (9) in its middle in the longitudinal direction.  4. Anti-return key piece according to claims 1 to 3 is characterized in that the inclined wall (10) of the trapezoid is cut at 12 so that its end is detached from the plate 6 and makes it elastic .  5. anti-return key piece according to claims 1 to 4 taken as a whole is characterized in that the outer surfaces of the walls (8) and (10) carry streaks of attachment.  6. anti-key return piece according to claims 1 to 5 taken as a whole is characterized in that it comprises a cradle (11) of a semi-round shape supporting a part of the key rod.  7. Key anti-return piece according to claims 1 to 5 taken as a whole is characterized in that the plate (6) curved front face extends on either side of the trapezoidal prism (7).  8. key anti-return piece according to claims 1 is characterized in that the elastic fixing means consists of a leg (14) provided with two elastic lips (15) inclined and striated on the hooking faces.  9. key anti-return piece according to claims- let 6 is characterized in that the elastic fixing means is constituted by a prism 16 massive rectangular trapezoidal very elastic material, such as rubber whose surfaces 17 carry bosses hanging.