LOCK

Abstract: An automatic mechanical lock, particularly for a vehicle door or doors comprises two body portions, one body portion to be mounted on the door at an edge thereof and the other body portion to be mounted adjacent the door and overlapping the edge of the door, a first of the body portions carrying a hasp (12) to receive a spring-mounted bolt (22), and the second body portion (20) carrying the spring-mounted bolt (22) and having an aperture (25) to receive the hasp (12), the bolt (22) being biased by the spring (23) to a position where it can engage the hasp (12) to lock the door, a key mechanism (32, 32A), which when the key is turned in the lock from a first position to a second position, slides the bolt (22) away from the hasp (12) against the action of the spring (23) whereby the door may be opened, an arm (27) movable to engage a slot (24) in the bolt (22) when the key is returned from the second position to the first position to prevent the bolt (22) re-engaging the hasp (12), whereby the door can still be opened, and an actuator (29) spring-biased (30) to block the passage of the bolt (22) when the hasp (12) is removed on opening the door and to allow the hasp (12) to re-enter the aperture (25) on closing of the door, the actuator (29) releasing the arm from the slot in the bolt when the actuator moves to block to the passage of the bolt, whereby when the door is closed, the hasp (12) moves the actuator (29) from its blocking position and the bolt is sprung through the hasp (12).

Description: LOCK This invention relates to a lock and particularly to a mechanical lock for a door or the like, which closes automatically to provide a high degree of security. The lock of the invention is particularly useful, for example, on rear doors of commercial vehicles but its use is in no way limited thereto. However, for convenience, it will be further described below with particular reference to commercial vehicle doors. There is a need currently for a secure lock on the rear doors of commercial vehicles so that the doors will lock automatically when closed. Thus, for example, when the driver or other person removes goods from the vehicle and carries them away from the vehicle, merely pushing the doors to the closed position or allowing them to close under other positive action will lock the vehicle and render it inaccessible to unauthorised access in the driver's absence. Accordingly, the invention provides a lock for a door, wherein the lock comprises two body portions, one body portion to be mounted on the door at an edge thereof and the other body portion to be mounted adjacent the door and overlapping the edge of the door, a first of the body portions carrying a hasp to receive a spring- mounted bolt, and the second body portion carrying the spring-mounted bolt and having an aperture to receive the hasp, the bolt being biased by the spring to a position where it can engage the hasp to lock the door, a key mechanism, which when the key is turned in the lock from a first position to a second position, slides the bolt away from the hasp against the action of the spring whereby the door may be opened, an arm movable to engage a slot in the bolt when the key is returned from the second position to the first position to prevent the bolt re-engaging the hasp, whereby the door can still be opened, and an actuator spring - biased to block the passage of the bolt when the hasp is removed on opening the door and to allow the hasp to re-enter the aperture on closing of the door, the actuator releasing the arm from the slot in the bolt when the actuator moves to block the passage of the bolt, whereby when the door is closed, the hasp moves the actuator from its blocking position and the bolt is sprung through the hasp. Thus, when the key is turned to the second position to render the door openable, it may then be turned back to the first position and, if desired, removed from the lock. The door is still then openable and, when opened, the bolt is prevented from moving to its biased locked position by the actuator. The bolt, therefore, cannot prevent re-entry of the hasp into the second body portion when the door is re- closed and closure of the door moves the actuator to allow the bolt to spring into the locked position. The hasp may be of conventional construction to receive the spring-mounted bolt but equivalent mechanical means may also be employed. For example, the hasp may take the form of a notched arm or bolt wherein the spring-mounted bolt may be engaged by being received in the notch. The lock may advantageously be used on a pair of co-operating doors with one body portion mounted adjacent the respective edge of each door. Alternatively, one body portion may be mounted on a door or the other on a frame of the door. In one specific form of this latter embodiment the invention has particular applicability as a lock for a so-called plug-fit vehicle door. Such doors are well known and are side-mounted, sliding doors which, on opening, move outwardly and then slide in a track parallel to the side of the vehicle. In this embodiment one body portion of the lock is mounted on the sliding door and the other on a fixed portion of the vehicle body, e.g. a pillar, adjacent an edge of the sliding door. It will be appreciated that in such usage, the dimensions of one or both of the lock body portions may need to be restricted and the aforementioned construction using a hasp in the form of a notched arm or bolt has been found to be particularly suitable, particularly with the first body portion (carrying the hasp) mounted on the sliding door and the second body portion mounted, preferably internally, on the door pillar. The spring-mounted bolt may conveniently pass through a hole in a buttress attached to the second body portion and positioned adjacent the aperture for the hasp. The arm to engage the slot in the bolt may then conveniently be positioned to operate on the side of the buttress away from the aperture and the actuator on the opposite side of the buttress in line with the aperture. The actuator and the arm may be connected by any convenient means. Thus, they may be pivotally connected together so that the arm can move to engage the slot on the bolt by spring bias means while the actuator is prevented from moving by the hasp in the aperture. When the hasp is removed, the actuator is biased to move to block movement of the rod while overcoming the bias of the arm to move the arm from the slot in the bolt. An internal release device may be fitted if desired, particularly in the case of commercial vehicles. The key mechanism may conveniently rotate an arm to engage a plate attached to the bolt whereby the plate and hence the bolt is moved against the spring bias when the key is turned from the first position to the second position. Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 and Figure 1A are a side and a rear view respectively of the second body portion in the locked position; Figure 2 is a top view of the second body portion after the key has turned the lock to the second position; Figure 3 and Figure 3A illustrate the configuration when the key has been returned from the second to the first position while still in the 'door closed' position; and Figure 4 and Figure 4A illustrate the next, i.e. 'door open' stage. In Figures 1 and 1 A second body portion 20 comprises a housing 21 containing a bolt 22 which is biased by spring mechanism 23 into the locked position. Bolt 22 is also shown in Figure 1A passing through a hasp 12. As shown, hasp 12 has entered aperture 25 in housing 11. The hasp 12 is attached to a first body portion (not shown for clεuity). The body portions may be mounted on adjacent opening doors (not shown). Adjacent its end to engage the hasp 12, bolt 22 has a slot 24. Bolt 22 passes through a hole in a buttress 26 mounted in housing 21. An arm 27 is mounted by spring 28 on buttress 26 and biased into contact with bolt 22. On the opposite side of buttress 26 an actuator 29 is also mounted to the buttress by spring 30 into contact with the opposite side of bolt 22. Arm 27 is pivotally connected to actuator 29 by pin 31 which also passes through buttress 26 and springs 28 and 30. The key mechanism is operated by a key (not shown) inserted into a keyhole 32 (Figure 2) in the face of housing 21 at the opposite end of lock barrel 32A. An arm 33 is mounted on barrel 32A and carries on its opposite end a wheel 34 which is to bear on a plate 35 through which bolt 21 passes. When the key is turned through 90° in the lock, the position shown in Figure 2 is reached. Arm 33 has rotated with the turning of the key to bear wheel 34 against plate 35 and move plate 35 to the left, thereby moving bolt 22 to the left against the spring 23, which is thereby compressed. The bolt is thereby removed from the hasp. In Figures 3 and 3A, the next position is shown. The key has been turned back through 90°, i.e. from its second position back to its first position. Hasp 12 is still in aperture 25 as the door has not been opened. Arm 27 has been biased by spring 28 to engage slot 24 in bolt 22. Hence the bolt cannot return to engage hasp 12. Actuator 29 is spring biased to contact the far side of hasp 12. The key may be removed. If the door is now opened the configuration of Figures 4 and 4A is achieved. Hasp 12 moves out of body portion 20 allowing actuator 29 to be sprung across the end of bolt 22. In the same movement actuator 29 overcomes the bias of spring 28 and moves arm 27 out of the slot 24 in bolt 22. Thus, the bolt is held in the open position by actuator 29 with the door open. When the door is closed hasp 12 will force actuator 29 away from the end of bolt 22 which under the force of spring 23 will enter the hasp to return to the door locked position of Figures 1 and 1A.

Claims: CLAIMS A lock for a door, wherein the lock comprises two body portions, one body portion to be mounted on the door at an edge thereof and the other body portion to be mounted adjacent the door and overlapping the edge of the door, a first of the body portions carrying a hasp (12) to receive a spring- mounted bolt (22), and the second body portion (20) carrying the spring- mounted bolt (22) and having an aperture (25) to receive the hasp (12), the bolt (22) being biased by the spring (23) to a position where it can engage the hasp (12) to lock the door, a key mechanism (32, 32A), which when the key is turned in the lock from a first position to a second position, slides the bolt (22) away from the hasp (12) against the action of the spring (23) whereby the door may be opened, an arm (27) movable to engage a slot (24) in the bolt (22) when the key is returned from the second position to the first position to prevent the bolt (22) re-engaging the hasp (12), whereby the door can still be opened, and an actuator (29) spring - biased (30) to block the passage of the bolt (22) when the hasp (12) is removed on opening the door and to allow the hasp (12) to re-enter the aperture (25) on closing of the door, the actuator (29) releasing the arm from the slot in the bolt when the actuator moves to block the passage of the bolt, whereby when the door is closed, the hasp (12) moves the actuator (29) from its blocking position and the bolt is sprung through the hasp (12). 2. A lock according to Claim 1, wherein the hasp (12) is in the form of a notched arm or bolt wherein the spring-mounted bolt (22) may be engaged by being received in the notch. 3. A lock according to Claim 1 or 2, wherein it is mounted on a pair of cooperating doors with one body portion mounted adjacent the respective edge of each door. 4. A lock according to Claim 3, wherein one body portion is mounted on a door and the other body portion is mounted on a frame of the door. 5. A lock according to Claim 4, wherein the second body portion (20) is mounted on the door frame. 6. A lock according to any preceding claim, wherein the spring-mounted bolt (22) passes through a hole in a buttress (26) attached to the second body portion (20) and positioned adjacent the aperture (25) for the hasp (12). 7. A lock according to Claim 6, wherein the arm (27) to engage the slot (24) in the bolt (22) is positioned to operate on the side of the buttress (26) away from the aperture and the actuator (29) is on the opposite side of the buttress (26) in line with the aperture (25). 8. A lock according to any preceding claim, wherein the actuator (29) and the arm (27) are pivotally connected together so that the arm can move to engage the slot (24) in the bolt (22) by spring bias means while the actuator (29) is prevented from moving by the hasp (12) in the aperture. 9. A lock according to any preceding claim, wherein the key mechanism (32 A) rotates an arm (33) to engage a plate (35) whereby the bolt (22) is moved against the spring bias when the key is turned from the first position to the second position.

Inventors: DYKE ROBERT WILLIAM HENRY, DYKE, ROBERT, WILLIAM, HENRY
Applicants: DYKE ROBERT WILLIAM HENRY, EXPRESSLOCK LIMITED, DYKE, ROBERT, WILLIAM, HENRY
Application year: 1998
Main classification: E05B63
IPC codes: E05B63, E05B65, E05C19