GB2213863A

GB2213863A - Door Securing Mechanism

Info

Publication number: GB2213863A
Application number: GB8729582A
Authority: GB
Inventors: Frederick George Dover
Original assignee: Dover Roller Shutters Ltd
Current assignee: Dover Roller Shutters Ltd
Priority date: 1987-12-18
Filing date: 1987-12-18
Publication date: 1989-08-23
Also published as: GB8729582D0

Abstract

A door securing mechanism, particularly for a roller shutter door, comprises a hook (15) and a keep bar (16), the hook (15) being mounted on the door (10) by way of shaft (13) and the keep bar (16) being mounted on the floor (11). A handle (14) is connected to the hook (15) and is movable with the hook (15) between a secured position in which the hook (15) is engaged with the keep bar (16) and an opening position in which they are out of mutual engagement. The handle (14) has a recessed cylinder (17) attached into which recess (18) a bolt (20) may move, biassed by spring (22), thus locking the door. The door may be unlocked by inserting a key into lock (24); turning of the key moves arm (26) thus withdrawing the bolt (20) from the recess (18) and allowing the handle (14) to be pivoted to open the door (10). <IMAGE>

Description

DOOR SECURING MECHANISM This invention relates to a door securing mechanism, and has particular but not exclusive application to roller shutter doors or other sliding doors.

Roller shutter doors or other forms of sliding doors are often used in commercial rather than domestic situations, in which case the closing of the door may be the responsibility of any number of people. In such situations there is a risk of the person closing the door not ensuring that the door is properly closed and locked through either carelessness or lack of understanding of the necessary operation of whatever closing and locking system is provided on a particular door.

In the case of roller shutter doors or other sliding doors, it is often the case that locking is effected by means of a padlock which secures together either two brackets or bosses which are mutually adjacent when the door is closed, one bracket or boss being attached to the door and one to the door jamb, cill or other surrounding structure, or the door handle and a bracket or boss which is adjacent the handle when the door is in the closed position, the bracket or boss being on the door jamb, cill or other surrounding structure. With such an arrangement often people omit or forget to engage the padlock or the padlock is not available so that the door remains unlocked. In addition, even if the door is locked in this way, it is often not too-difficult to either prise the lock or bracket off the assembly or cut the lock with bolt cutters.Such a door securing mechanism does not therefore provide a wholly satisfactory security arrangement in many circumstances.

It is an object of the present invention to provide a door securing mechanism-which avoids, at least to a substantial extent, the disadvantages-referred to above.

The invention provides a door securing mechanism for securing a door to an adjacent structure, comprising mutually engageable members adapted to be mounted each on one of said door and said adjacent structure, a handle connected to one of said engageable members and movable with said one engageable member between a secured position in which said engageable members are mutually engaged and an opening position in which said engageable members are out of mutual engagement, said handle having a retaining part and said mechanism comprising retaining means operable to engage said retaining part to prevent movement of said handle from said secured position thereof, and locking means operable to move said retaining means out of engagement with said retaining part.

Preferably said locking means is a key operated locking means, and may comprise a cylinder locking means.

In that case the cylinder of said locking means may have an arm which engages said retaining means. Said retaining means may comprise a bolt slidably mounted in a housing, and said retaining means may be resiliently biassed towards said retaining part.

Said handle may be mounted to rotate about an axis of a shaft, and said retaining part may comprise a cylinder rotatable about said axis. In that case said retaining part may have a recess in the cylindrical surface thereof adapted to receive said retaining means therein.

Said one of said engageable members may comprise a hook. Said handle may be connected to said door, in which case the other of said engageable members may be connected to said adjacent structure. Said other of said engageable members may comprise a keep bar disposed to be engaged by said hook when said door is in a door closed position, and said keep bar may be located in a floor upwardly and downwardly relative to which said door is adapted to move.

One embodiment of door securing mechanism in accordance with the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a front elevation, and Fig. 2 is a rear elevation partly in section.

Referring now to the figures there is shown part of a door 10 which in this case is a roller shutter door of the type which may be fitted to the rear or sides of a motor vehicle, for example delivery vans, fire engine lockers or the like. Such a door 10 is adapted to move upwardly and downwardly relative to a floor 11. When the door 10 is in the closed position as shown in the figures, the bottom edge 12 of the door 10 abuts or is closely adjacent the floor 11. Mounted in the door 10 is a shaft 13 to which is secured a handle 14.Connected to the handle 14 is a hook 15 whereby the hook 15 moves with the handle 14 when the latter is pivoted about the axis of the shaft 13. When-the door 10 is in the closed position as shown, rotation of the handle 14 in a clockwise direction causes the hook 15 to engage a keep bar 16 secured in the floor llo With such an arrangement the door 10 would be closed but not locked.

Also secured to the shaft 13, but at the rear of the door 10, as shown in Fig. 2, is a retaining part 17 in the form of a cylinder having a recess 18 in the cylindrical surface thereof. Mounted on the rear of the door 10 is a bolt housing 19 which is shown partly cut away in Fig. 2 to show a bolt 20 slidably received in the bolt housing 19. A peg 21 which passes through the bolt 20 provides a stop for one end of a compression spring 22, the other end of which abuts the end of a slot 23 provided in the bolt housing 19 to accommodate the spring 22. By this means the bolt 20 is resiliently biassed towards the retaining part 17 whereby the end of the bolt 20 is received in the recess 18 when the handle 14 and hook 15 are in the door closed position as shown.

Also mounted in the door 10 is a lock 24 of the cylinder type. Attached to the cylinder 25 of the lock 24 at the rear of the door 10 is an arm 26, the free end of which is received in a slot 27 provided in the bolt 20. With the complete arrangement as has now been described in the configuration shown in the figures, the door 10 is both closed and securely locked. The handle 14 cannot be pivoted so as to allow disengagement of the hook 15 from the keep bar 16 since such movement is prevented by the presence of the end of the bolt 20 in the recess 18 in the retaining part 17. Since the bolt 20 is at the rear of the door 10, it cannot be withdrawn from the recess 18 without penetration of the door itself by some means, and such an operation would be very difficult if the door 10 and the door securing mechanism are made of suitably strong materials and of substantial dimensions.

To open the door 10 a key (not shown) is inserted in the lock 24 and is turned in a clockwise direction.

This causes rotation of the barrel 25 and movement of the arm 26 through an arc sufficient to withdraw the bolt 20 from the recess 18 against the force of the spring 22. The handle 14 may then be pivoted to cause the hook 15 to disengage from the keep bar- 16 so that the door 10 may be opened. Releasing the key allows the spring 22 to force the bolt 20 into contact with the cylindrical surface of the retaining part 17, so that when the door 10 is next closed and the handle 14 returned to the closing position, the bolt 20 will automatically enter the recess 18 under the force of the spring 22, thereby locking the door 10 in the door closed position. No further action on the part of the operative, other than removal of the key from the lock 24, is required to ensure secure locking of the door 10.

To prevent unintentional locking of the door in the door open position, a parrot keeper 28 is provided pivotally mounted on the outside of the door 10. A keeper part 29 is provided on the rear of the handle 14 and is of cylindrical form having a recess 30 provided in the cylindrical surface thereof. When the handle 14 is pivoted in an anti-clockwise direction sufficiently to ensure that hook 15 is completely disengaged from keep bar 16, the parrot keeper 28 can be pivoted so that the beak 31 thereof engages the recess 30 of the keeper part 29, thereby preventing pivoting of the handle 14 in a clockwise direction. The parrot keeper 28 may be resiliently biassed towards the keeper part 29 if desired so that such latching of the handle 14 in the open position occurs automatically.when the handle 14 is pivoted sufficiently.

Other embodiments of door securing mechanism in accordance with the invention will be readily apparent to persons skilled in the art. For example, the barrel 25 may be formed as a pinion and the bolt 20 as a rack in engagement therewith. Instead of the provision of spring 22, movement of the bolt 20 may be effected in both directions by turning of the key in the appropriate sense. As a further alternative, the arm 25 engages the retaining part 17 directly without the intermediary of a bolt 20c By means of the invention a door securing mechanism is provided whereby locking of the door in the door closed position is automatic or semi-automatic, the only action required on the part of the operative being removal of a key. The invention, although described in relation to a roller shutter door, is equally suitable for use with sliding doors or conventionally opening pivoting doors if desired.

Claims

1. A door securing mechanism for securing a door to an adjacent structure, comprising mutually engageable members adapted to be mounted each on one of said door and said adjacent structure, a handle connected to one of said engageable members and movable with said one engageable member between a secured position in which said engageable members are mutually engaged and an opening position in which said engageable members are out of mutual engagement, said handle having a retaining part and said mechanism comprising retaining means operable to engage said retaining part to prevent movement of said handle from said secured position thereof, and locking means operable to move said retaining means out of engagement with said retaining part.

2. A door securing mechanism according to claim 1 wherein said locking means is a key operated locking means.

3. A door securing mechanism according to claim 2 wherein said locking means comprises a cylinder locking means.

4. A door securing mechanism according to claim 3 wherein the cylinder of said locking means is provided with an arm which engages said retaining means.

5. A door securing mechanism according to any one of claims 1 to 4 wherein said retaining means comprises a bolt slidably mounted in a housing.

6. A door securing mechanism according to any one of claims 1 to 5 wherein said retaining means is resiliently biassed towards said retaining part.

7. A door securing mechanism according to any one of claims 1 to 6 wherein said handle is mounted to rotate about an axis of a shaft.

8. A door securing mechanism according to claim 7 wherein said retaining part is a cylinder rotatable about said axis.

9. A door securing mechanism according to claim 8 wherein said retaining part has a recess in the cylindrical surface thereof adapted to receive said retaining means therein.

10. A door securing mechanism according to any one of claims 1 to 9 wherein said one of said engageable members comprises a hook.

11. A door securing mechanism according to claim 10 wherein the other of said engageable members comprises a keep bar disposed to be engaged by said hook when said door is in a door closed position.

12. A door securing mechanism according to claim 11 wherein said keep bar is located in a floor upwardly and downwardly relative to which said door is adapted to move.

13. A door securing mechanism substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

14. A door provided with a mechanism according to any one of claims 1 to 13.

15. A roller shutter door provided with a mechanism according to any one of claims 1 to 13.