GB2385882A

GB2385882A - A lockable door operating mechanism

Info

Publication number: GB2385882A
Application number: GB0204804A
Authority: GB
Inventors: Stephen Tinsley
Original assignee: EUROSPEC ARCHITECTURAL HARDWAR
Current assignee: EUROSPEC ARCHITECTURAL HARDWAR
Priority date: 2002-03-01
Filing date: 2002-03-01
Publication date: 2003-09-03
Also published as: GB0204804D0

Abstract

A locking means 14 comprises stop means 20 including an actuator plate 22, a stop plate 24, abutment means 32, and displacement means 26. The actuator plate 22 is attached to a lever handle 16 which operates a conventional bolt and bolt receiver (not shown). To lock the mechanism a cam 44 is rotated which raises stop plate 24 so that abutment mean 32 contacts actuator plate 22 disabling rotation.

Description

A lockable door operating mechanism. The present invention relates to door operating mechanisms and particularly to lockable door operating mechanisms.

Doors, of the type used to cover openings in external and internal elevations of buildings, are generally retained in a closed position by means of a latch mechanism having a bolt which is moveable into, to thereby engage, a bolt receiver disposed in framework adjacent the door.

The mechanism is usually biassed to retain the latch bolt in the engaged position.

The latch bolt is shaped so that, on closing the door, it abuts and rides over a receiver plate, overcoming the bias until it engages the receiver wherein it retains the door in a closed position. The latch bolt remains engaged with the receiver until the handle or knob is rotated to overcome the bias and thereby withdraw the latch bolt sufficiently to overcome the depth of the receiver, before carrying the receiver over the receiver plate, to open the door.

In addition to a latch mechanism, a lock mechanism is often used to secure a door in a closed position. A commonly used lock mechanism is known as a sash lock. A sash lock comprises a manually slidable bolt, disposed on the door, and slidable into a receiver disposed on a frame adjacent the door, to secure the door in a closed position.

Another type of lock mechanism is a dead lock which comprises a moveable bolt, disposed on the door, which is moveable into a bolt receiver, disposed on a frame adjacent the door, to secure the door closed. The bolt is usually moved into the receiver by turning a key or a knob clockwise and withdrawn from the receiver by turning the key or knob anticlockwise.

The abovementioned latch and lock mechanisms have the disadvantage of requiring two separate mechanisms and bolts, increasing the cost of manufacturing and installation thereof.

It is also known to combine a latch mechanism and a dead lock. An example of such a lock mechanism is a type which is commonly known as a"YALE"lock. This type of lock generally comprises a moveable bolt operable to engage a receiver, disposed on a frame adjacent the lock mechanism. The bolt is shaped and biassed as the abovementioned latch bolt, that is, to engage the receiver, and may be secured in either a position which engages or disengages the receiver. The bolt is moved from the engaged position to the disengaged position by rotating a lever or knob. The bolt is secured in either position by activating a mechanism which physically prevents movement of the bolt.

These combined latch and lock mechanisms are relatively complex and therefore relatively expensive and prone to jamming after prolonged use.

It is an object of the present invention to provide a lockable door operating mechanism which is inexpensive to manufacture and install, and is mechanically simple and enduring.

According to the present invention a lockable door operating mechanism for use with latching means having a bolt operable to engage a bolt receiver disposed on a door frame to thereby retain a door in a closed position, the mechanism comprising disengaging means having a rotatably displaceable actuator, operable to withdraw the bolt thereby disengaging it from the receiver, and locking means adapted to secure the bolt in a predetermined position, characterised in that the locking means comprises stop means operable to prevent substantial rotational displacement of the actuator thereby securing the bolt in a predetermined position.

The stop means advantageously comprises an actuator plate adapted to communicate with the actuator, a stop plate having abutment means, and displacement means operable to displace the stop plate between a first position, spaced apart from the actuator plate thereby allowing rotational displacement of the actuator, and a second position in which the abutment means abuts the actuator plate preventing rotational displacement of the actuator thereby locking the bolt in a predetermined position.

The stop plate may comprise a cam following surface. The displacement means may comprise a cam, mounted on a pivot pin, having a cam surface. The cam is arranged so that the cam following surface communicates with the cam surface. In use, the cam may be rotated causing

the cam following surface to ride over the cam surface displacing the stop plate between the first and second positions.

Advantageously, at least one of the abutment means and the actuator plate may be shaped to bias the rotatably displaceable actuator to secure the bolt in one or more predetermined positions. The predetermined positions may be an engageable position or an unengageable position.

The actuator plate may be attached to the rotatably displaceable actuator and is preferably adapted to rotate relative to the rotation of the rotatably displaceable actuator.

The abutment means may form part of the stop plate and preferably comprises at least one raised region thereof.

The stop plate may also comprise a slot through which the pivot pin, carrying the cam, extends and travels relative to the stop plate during displacement thereof between the first and second positions.

The displacement means may also comprise travel limitation means operable to restrict the travel of the plate between predetermined positions. The limitation means may comprise an elongate arm, operable to rotate relative to the rotation of the cam, and at least one abutment, each operable to prevent arm travelling beyond a predetermined position. The elongate arm is

preferably disposed on the cam and the, or each, abutment is preferably disposed on the stop plate.

The rotatably displaceable activator may be a lever handle. Alternatively, the rotatably displaceable activator may be a knob. The rotatably displaceable activator may comprise biassing means operable to bias the activator into a position which activates engagement of the bolt with the receiver. The biassing means may comprise a spring.

The present invention will be described further, by way of example, with reference to the accompanying drawings in which: Figure 1 is an elevation of a lockable door operating mechanism, disposed in a disengaged and unsecured arrangement, according to the present invention; Figure 2 is an elevation of the lockable door operating mechanism shown in Figure 1, disposed in an engaged and secured arrangement; Figure 3 is an elevation of the stop plate shown in Figures 1 and 2; Figure 4 is a side elevation of the stop plate shown in Figure 3; and, Figure 5 is a plan view of the stop plate shown in Figures 3 and 4.

Referring to the drawings, according to the present invention a lockable door operating mechanism 10 comprises standard latching means (not shown), disengaging means 12 and locking means 14.

The latching means comprises a bolt operable to engage a bolt receiver disposed on a standard door frame (not shown) to retain a door in a closed position.

The disengaging means 12 comprises a lever handle 16 operable to disengage the bolt from the receiver. The lever handle 16 is biassed by a spring 18 into a position which activates engagement of the bolt with the receiver.

The locking means 14 comprises stop means 20 including an actuator plate 22, a stop plate 24 and displacement means 26.

The actuator plate 22 is attached to the lever handle 16 and comprises an engaged securing edge 28 and a disengaged securing edge 30.

The stop plate 24 comprises abutment means 32, having a first abutment edge 34 and a second abutment edge 36, a cam following surface 38, a slot 40 and travel limiting means 42.

The displacement means 26 comprises a cam 44, mounted on a pivot pin 45, having a cam surface 46 operable to communicate with the cam following surface 38 and thereby displace the stop plate 24 between a first position, in which it allows movement of the lever handle 16 (Figure

1), and therefore the bolt, and a second position in which it secures the lever handle 16 (Figure 2) thereby locking the bolt in either an engaged position or a disengaged position, relative to the receiver.

The travel limiting means 42 comprises an elongate arm 48 disposed on the cam 44 to extend radially outwards therefrom, and first, second and third abutments, 50,52 and 54, respectively, operable to abut the elongate arm 48 and part of the cam surface 46 to restrict the rotational travel of the cam 44.

Figure 1 shows the door operating mechanism 10 in an unlocked arrangement whereby the lever handle 16 is free to be rotated to engage or disengage the bolt with the receiver. Figure 1 actually shows the lever in a position, against the bias of the spring 18 (out of view), which actuates the disengagement of the bolt from the receiver. The cam 44 is at rest and is prevented from travelling in an anti-clockwise direction by the first abutment 50, abutting the cam surface 46, and the second abutment 52, abutting the elongate arm 48.

From the arrangement shown in Figure 1, to lock the door operating mechanism 10 so that the bolt is secured in an engaged position relative to the receiver, the cam 44 is rotated so that the cam surface 46 communicates with the cam following surface 38. Further rotation of the cam 44 causes the cam following surface 46 to ride over the cam surface 46 thereby raising the stop plate 24, on which the cam following surface 46 is disposed, towards the actuator plate 22.

Once the cam 44 has been rotated about approximately 900 the elongate arm 48 abuts the third abutment 54 thereby preventing further rotation of the cam 44 in a clockwise direction, as shown in Figure 2. In this arrangement, the stop plate 24 is raised to a maximum height whereby the first abutment edge 34, disposed on the stop plate 24, abuts the engaged securing edge 28, disposed on the actuator plate 22, thereby locking the lever handle 16 in a position which actuates engagement of the bolt with the receiver.

To lock the door operating mechanism 10 (from an unlocked arrangement as shown in Figure 1) so that the bolt is secured in a disengaged position, relative to the receiver, the abovementioned procedure is carried out whilst retaining the lever handle 16 in a position which actuates the bolt in a position which does not engage the receiver.

The lever handle 16 is released from either locked position by rotating the cam 44 anticlockwise thereby lowering the stop plate 24 thereby allowing rotation of the lever handle 16.

Claims

Claims: 1. A lockable door operating mechanism for use with latching means having a bolt operable to engage a bolt receiver disposed on a door frame to thereby retain a door in a closed position, the mechanism comprising disengaging means having a rotatably displaceable actuator, operable to withdraw the bolt thereby disengaging it from the receiver, and locking means adapted to secure the bolt in a predetermined position, characterised in that the locking means comprises stop means operable to prevent substantial rotational displacement of the actuator thereby securing the bolt in a predetermined position.
2. A lockable door operating mechanism as claimed in Claim 1, wherein the stop means comprises an actuator plate, adapted to communicate with the actuator, a stop plate having abutment means, and displacement means operable to displace the stop plate between a first position, spaced apart from the actuator plate thereby allowing rotational displacement of the actuator, and a second position in which the abutment means abuts the actuator plate preventing rotational displacement of the actuator, thereby locking the bolt in a predetermined position.
3. A lockable door operating mechanism as claimed in Claim 2, wherein the stop plate comprises a cam following surface and the displacement means comprises a cam, having a cam surface, mounted on a pivot pin, whereby rotation of the cam causes the

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cam following surface to ride the cam surface thereby displacing the stop plate between the first position and the second position.
4. A lockable door operating mechanism as claimed in Claims 2 and 3, wherein the abutment means and the actuator plate is shaped to bias the rotatably displaceable actuator and thereby secure the bolt in one or more predetermined positions.
5. A lockable door operating mechanism as claimed in Claim 4, wherein the abutment means and the actuator plate is shaped such that the bolt may be secured in an extended position or a withdrawn position.
6. A lockable door operating mechanism as claimed in Claims 2 to 5, wherein the actuator plate is attached to the rotatably displaceable actuator.
7. A lockable door operating mechanism as claimed in Claims 2 to 6, wherein the actuator plate is adapted to rotate relative to the rotation of the rotatably displaceable actuator.
8. A lockable door operating mechanism as claimed in Claims 2 to 7, wherein the abutment means comprises at least one raised region of the stop plate.
9. A lockable door operating mechanism as claimed in Claims 3 to 8, wherein the stop plate comprises a slot through which the pivot pin is disposed and travels, relative to the stop plate, during displacement of the stop plate between the first position and the second position.

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10. A lockable door operating mechanism as claimed in Claims 3 to 9, wherein the displacement means comprises travel limitation means operable to restrict travel of the stop plate between predetermined positions.
11. A lockable door operating mechanism as claimed in Claim 10, wherein the limitation means comprises an elongate arm operable to rotate relative to the rotation of the cam, and at least one abutment operable to prevent travel of the arm beyond a predetermined position.
12. A lockable door operating mechanism as claimed in Claim 11, wherein the elongate arm is disposed on the cam and the, or each, abutment is disposed on the stop plate.
13. A lockable door operating mechanism as claimed in any of the preceding claims, wherein the rotatably displaceable activator is a lever handle.
14. A lockable door operating mechanism as claimed in Claims 1 to 12, wherein the rotatably displaceable activator is a knob.
15. A lockable door operating mechanism as claimed in any of the preceding claims, wherein the rotatably displaceable activator comprises biassing means operable to bias the activator in a position which activates engagement of the bolt with the receiver.
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j. A lockable door operating mechanism as claimed in Claim 15, wherein the biassing means is a spring.
17. A lockable door operating mechanism as claimed in any of the preceding claims in combination with latching means having a bolt operable to engage a bolt receiver disposed on a door frame.
18. A lockable door operating mechanism as herein described with reference to, as shown in, the accompanying drawings.