GB2136046A

GB2136046A - Lock with means for shutting off the key channel

Info

Publication number: GB2136046A
Application number: GB08404115A
Authority: GB
Inventors: Ralph J A Marsh
Original assignee: RHONE ISERE
Current assignee: RHONE ISERE
Priority date: 1983-03-03
Filing date: 1984-02-16
Publication date: 1984-09-12
Also published as: GB2136046B; FR2542033A1; FR2542033B1; GB8404115D0

Abstract

The invention relates to a lock with a member 4 secured at its rear, and a shutter 9 for shutting off the key channel outlet opposite to the key inlet mounted on the member 4. As shown the shutter is pivotably mounted at 10 but in another embodiment the shutter slides on the member 4. <IMAGE>

Description

SPECIFICATION Lock with movable cam with means for shutting off the key channel The invention relates to a lock with a movable cam, comprising means for shutting off the key channel, in order to prevent the lock from being used in certain circumstances.

For post office boxes certain locks are known in which the key channel is open opposite to the key inlet and a shutter of which the pivotal point is a shaft integral with the internal wall of the box is able to shut off the key channel at the point where it leads into the box. The key then cannot be inserted in its entirety and the lock cannot be operated. The shutter is placed in position from inside the box after a door in the rear face of the box has been opened, when the user of the box, for example, has failed to pay the rental due, so that he is thus deprived of access thereto.

These known locks suffer from a number of drawbacks. In particular, their assembly is a fairly delicate operation, as the pivoting shutter has to be articulated to the wall of the box and adjusted so that it can perform its function. Furthermore, the pivotal point is at a considerable distance from the key channel, so that the movement easily becomes subject to play or clearance, thus rendering the system less secure.

The purpose of the present invention is to improve the locks of the aforementioned type, rendering them easier to assemble and more reliable in operation.

For this purpose, the invention relates to a lock with a movable cam, the key channel being open opposite to the key inlet, a shutter being provided for shutting off the channel outlet opposite to the key inlet, characterized by the fact that the said shutter is mounted on the movable cam.

The lock according to the invention is mounted like a normal lock, while the method by which the movable cam is secured also provides the means for mounting and positioning the shutter.

The invention will be clearly understood from a study of the following description, which is given by reference to the attached drawing, wherein: Fig. 1 is a schematic plan view of a lock according to one embodiment of the invention, in the normal position of use; Fig. 2 is a plan view analogous to that of Fig. 1, the lock being shown in the blocked position; Fig. 3 is à side elevation, in the blocked position, of a lock according to a second embodiment of the invention; Fig. 4 is an analogous view to Fig. 3, the lock occupying the normal operating position.

In the two versions described and shown as examples the same reference number for a given component is retained throughout.

The lock comprises a bar 1 or rotor 1 journalled in a stator 2 secured by means of a nut 3 in a door (not shown). A movable cam 4 is affixed by means of a nut 6 to that end of the barrel 1 which is opposite to the key entry 5.

Opposite the key entry 5 the key channel is open. In the case of Figs. 1 and 2 the opening 7 of the key channel is unobstructed, whereas in the case of Figs. 3 and 4 it contains a sliding pin 8.

According to the invention a shutter 9 mounted on the movable cam 4 can occupy a normal operating position in which it leaves the opening 7 of the key channel unobstructed and a blocked position in which it re-covers the opening 7 of the key channel. In the first position the key (not shown) can be inserted in its entirety into the key channel, either with its point projecting from the opening 7 (as in Figs. 1 and 2) or thrusting the pin 8 out of the key channel (as in Figs. 3 and 4). In the blocked position, on the other hand, the key cannot be completely inserted in the key channel and the lock cannot be operated.

In the embodiment shown in Figs. 1 and 2 the shutter 9 is pivotably mounted on a shaft 10 and is held in the blocked position by a stop 11.

In the variant shown in Figs. 3 and 4 the shutter 9 is slidably mounted on the movable cam 4 and is guided by bent parts 1 2 sliding against the two edges of the movable cam 4. The shutter 9 includes a crank-shaped section 1 3 which, when situated opposite the lock shaft (Fig. 4), enables the point of the key or of the pin 8 to emerge.

1. Lock with a movable cam, the key channel being open opposite to the key inlet, with a sbutter off the key channel outlet opposite to the key inlet, characterized by the fact that the said shutter 9 is mounted on the movable cam 4.

2. Lock in accordance with claim 1, characterized by the fact that the said shutter 9 is pivotably mounted on the movable cam 4.

3. Lock in accordance with Claim 1, characterized by the fact that the said shutter 9 is slidably mounted on the movable cam 4.

4. Lock in accordance with one of Claims 1-3, characterized by the fact that the outlet 7 of the key channel opposite the key inlet 5 is unobstructed.

5. Lock in accordance with one of Claims 1-3, characterized by the fact that the outlet 7 of the key channel opposite the key inlet 5 comprises a sliding pin 8.

6. Lock substantially as described by way of example with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Lock with movable cam with means for shutting off the key channel The invention relates to a lock with a movable cam, comprising means for shutting off the key channel, in order to prevent the lock from being used in certain circumstances. For post office boxes certain locks are known in which the key channel is open opposite to the key inlet and a shutter of which the pivotal point is a shaft integral with the internal wall of the box is able to shut off the key channel at the point where it leads into the box. The key then cannot be inserted in its entirety and the lock cannot be operated. The shutter is placed in position from inside the box after a door in the rear face of the box has been opened, when the user of the box, for example, has failed to pay the rental due, so that he is thus deprived of access thereto. These known locks suffer from a number of drawbacks. In particular, their assembly is a fairly delicate operation, as the pivoting shutter has to be articulated to the wall of the box and adjusted so that it can perform its function. Furthermore, the pivotal point is at a considerable distance from the key channel, so that the movement easily becomes subject to play or clearance, thus rendering the system less secure. The purpose of the present invention is to improve the locks of the aforementioned type, rendering them easier to assemble and more reliable in operation. For this purpose, the invention relates to a lock with a movable cam, the key channel being open opposite to the key inlet, a shutter being provided for shutting off the channel outlet opposite to the key inlet, characterized by the fact that the said shutter is mounted on the movable cam. The lock according to the invention is mounted like a normal lock, while the method by which the movable cam is secured also provides the means for mounting and positioning the shutter. The invention will be clearly understood from a study of the following description, which is given by reference to the attached drawing, wherein: Fig. 1 is a schematic plan view of a lock according to one embodiment of the invention, in the normal position of use; Fig. 2 is a plan view analogous to that of Fig. 1, the lock being shown in the blocked position; Fig. 3 is à side elevation, in the blocked position, of a lock according to a second embodiment of the invention; Fig. 4 is an analogous view to Fig. 3, the lock occupying the normal operating position. In the two versions described and shown as examples the same reference number for a given component is retained throughout. The lock comprises a bar 1 or rotor 1 journalled in a stator 2 secured by means of a nut 3 in a door (not shown). A movable cam 4 is affixed by means of a nut 6 to that end of the barrel 1 which is opposite to the key entry 5. Opposite the key entry 5 the key channel is open. In the case of Figs. 1 and 2 the opening 7 of the key channel is unobstructed, whereas in the case of Figs. 3 and 4 it contains a sliding pin 8. According to the invention a shutter 9 mounted on the movable cam 4 can occupy a normal operating position in which it leaves the opening 7 of the key channel unobstructed and a blocked position in which it re-covers the opening 7 of the key channel. In the first position the key (not shown) can be inserted in its entirety into the key channel, either with its point projecting from the opening 7 (as in Figs. 1 and 2) or thrusting the pin 8 out of the key channel (as in Figs. 3 and 4). In the blocked position, on the other hand, the key cannot be completely inserted in the key channel and the lock cannot be operated. In the embodiment shown in Figs. 1 and 2 the shutter 9 is pivotably mounted on a shaft 10 and is held in the blocked position by a stop 11. In the variant shown in Figs. 3 and 4 the shutter 9 is slidably mounted on the movable cam 4 and is guided by bent parts 1 2 sliding against the two edges of the movable cam 4. The shutter 9 includes a crank-shaped section 1 3 which, when situated opposite the lock shaft (Fig. 4), enables the point of the key or of the pin 8 to emerge. CLAIMS