GB2106979A - Door locks - Google Patents

Abstract

A door lock comprises a lockable, linearly moving latch bolt 6, having a single operating member 3 on the inside of the door, by which all the operating actions of the lock can be performed. The single operating member comprises a rotatable first part 3A and a linearly movable second part 3B, with the first part co-axially surrounding the second part. Retraction of the latch bolt against the force of a latch spring is performed by rotation of the first part of the knob. Locking means for locking the latch bolt in the retracted position is constructed and arranged to be operated by depression of the second part of the knob. <IMAGE>

Description

SPECIFICATION Door locks This invention relates to door locks provided with lockable latches.

According to the present invention, from one aspect, a door lock with a lockable linearly-moving latch bolt has an operating member, e.g. a knob, by which all the operating actions of the lock can be performed from inside the associated door when in use, the operating member having a first part in the form of an outer body and a relativelymovable second part surrounded by the outer body.

Viewed from another aspect, the invention comprises a door lock with a lockable linearlymoving latch bolt, and has a single operating member, e.g. knob, by which all the operating actions of the lock can be performed from inside the associated door when in use, the single operating member comprising a rotatable first part and a linearly-movable second part, the first and second parts together forming the complete member.

In a preferred construction, the said first part of the operating member coaxially surrounds the second part, forming a convenient operating knob.

In one form of the invention, the retraction of the latch bolt against the force of a latch spring is performed by rotation of the said first part of the knob.

Preferably the lock includes locking means for locking the latch bolt in the retracted position, the locking means being constructed and arranged to be operated by depression of said second part of the knob. This locking means may be arranged to be released, to unlock the retracted latch bolt, by rotation of the said first part of the knob in the opposite direction to that required in retraction of the latch bolt.

The lock may also include a second locking means operable to deadlock (block) the latch bolt in its latched position. This deadlocking means may be operated by rotation of the said first part of the operating member in the opposite direction to that required for retraction of the latch bolt, and is released by rotation of the said first part in the same direction as required for retraction of the latch bolt and prior to retraction.

For example, the lock may include a pivotally mounted rocker having an eccentric pin engaged in the slot in the guide plate and coupled to the said first part of the knob for rotation therewith whereby rotation of the first part of the knob is transformed by the pin and slot connection into linear retraction movement of the guide pin and latch bolt assembly. The rocker may be rotatable into a dead-centre position with respect to the guide plate, in which position by the engagement of its eccentric pin in the slot it deadlocks the latch bolt in the latched position. A spring-loaded locking plate may be provided to bear on the rocker and hold it resiliently in this dead-centre position.

With the use of a symmetrical slot in the guide plate, the rocker may be preset by means of a selectively positioned stop member to be free to rotate in only one or the other angular direction out of its dead-centre position, so that the lock can thus be very simply preset for use with either a left-hinged or a right-hinged door simply by the insertion of the stop member in the corresponding position in the lock; and it may be arranged for the position of the stop member to be changeable without any need to open the lock housing.

The lock may be arranged to be used in conjunction with a cylinder lock and keyhole mounted in the door, so that the latch can be retracted or deadlocked by rotation of a key inserted from outside the door into the cylinder block, as well as being operable in all its functions by means of the operating member inside the door.

The invention may be carried into practice in various ways, but one specific embodiment thereof will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 is a view of the exterior of a lock with an associated keeper, as it would be seen from inside a door when mounted thereon, Figure 2 is a view of the opposite face of the lock to that of Figure 1, namely the face which would be applied to a door when mounted thereon, Figure 3 is a view similar to Figure 2 but with the cover plate 2 removed to show the interior of the lock, showing the latch bolt and associated mechanism in the unlocked latching position of the bolt, Figure 4 is a view similar to Figure 3 but showing the latch bolt and associated mechanism in the withdrawn and lock-back setting of the bolt, Figure 5 is a view similar to Figures 3 and 4 but showing the latch bolt and associated mechanism in the advanced and deadlocked setting of the bolt, Figure 6 is a cross-section on the line A-B in Figure 5, but with the cover plate in position and with the latch bolt and associated mechanism in the setting shown in that Figure, and Figure 7 is a sectional view similar to Figure 6 but with the latch bolt and associated mechanism in the withdrawn and deadlocked setting of Figure 4.

In the illustrated embodiment, a door lock with a lockable latch comprises a housing 1 closed by a removable cover plate 2, the housing containing the whole operating and locking mechanism for the latch apart from the rotary knob 3, and the cover plate 2 protecting the internal mechanism.

Screws 4 secure the cover plate to the housing 1, as seen in Figures 2 and 6, the screws 4 being received by tapped bores in bosses 4A formed in the interior of the housing 1.

The lock shown is intended to be mounted on the inner face of a door, with that side of the housing 1 which is closed by the cover plate 2 being applied to the face of the door near its outer edge, remote from the hinge. A keeper 5 shown in Figure 1 will be mounted on the adjacent door jamb, the keeper providing a recess for engagement by the outer end of the latch bolt 6 when advanced into its latching position. The housing 1 and cover plate 2 are provided with registering holes 7 to receive screws for fixing the lock to the door and the keeper 5 has similar holes, A rotatable bush 9 is journalled in an aperture in the cover plate 2, and is secured by a circlip 10. A central aperture 11 of narrow parallel-sided form is formed in the bush.In use, a cylinder lock (not shown) incorporating a rotary lock cylinder with an outwardly accessible keyhole is mounted in the thickness of the door beneath the bush 9. A blade projects from the rotary lock cylinder so as to engage in the aperture 11, when the lock is mounted in the door, so that when a key is inserted in the keyhole from outside the door and is turned, the corresponding rotation of the lock cylinder and blade will rotate the bush 9.

The bush 9 is rivetted to a slotted cam plate 1 2 (see Fig. 6) in whose slot 13 is engaged the tip of an eccentric pin 14 carried by a pivoted rocker member 1 5 forming part of the internal mechanism in the housing 1, whereby the bush 9 and its cover plate 2 transmit a turning movement of the key to the mechanism for operating the latch.

The latch bolt 6 extends through an opening in the end wall of the housing 1 and is rigidly secured by screws 1 6 within the housing to a slidable guide plate 17. The guide plate 1 7 can slide to and fro in the direction of arrows X (Fig. 3) between fixed side guides 1 8 in the housing 1, and is formed with a transverse slot 1 9 of symmetrical profile through which extends the pin 14 of the rocker 1 5, whereby the sliding movement of the assembly of the latch bolt 6 and guide plate 1 7 is controlled. Tags 20 struck from the cover plate 2 and bent inwardly retain the guide plate 17 against disengagement from the pin 14.

The rocker 15 is journailed in a bearing 22 in the housing 1, and the operating knob 3 is fixedly mounted on a spigot portion 23 of the rocker 1 5 which projects outside the housing. The transverse slot 1 9 in the guide plate extending symmetrically on either side of the axis of symmetry 24 of the guide plate and latch bolt (which passes through the pivoted axis of the rocker 15) enables the lock to be preset very simply for retraction of the guide plate and latch bolt assembly by rotation of the rocker 8 in either angular direction.This enables the lock to be adapted very simply for use either with a door hinged along its left-hand edge or with a door which is hinged along its right-hand edge, simply by inserting a stop screw 25 through one or other of two holes 26 and 27 in the cover plate 2 and screwing the screw 25 into the corresponding one of two tapped sockets 26' and 27' in the interior of the housing 1. Thus when the stop screw 25 is inserted into the right-hand hole 26 and 26' as seen in Figures 2 and 5, the rocker 1 5 can only be turned from the centralised position of Figure 5 in the clockwise direction as seen in that figure, because the tail 1 5A of the rocker will engage the stop screw to prevent anti-clockwise rotation of the rocker beyond the centralised position.

Similarly, if the stop screw 25 is removed from the hole 26 and socket 26' and is inserted into the hole 27 and socket 27', its engagement with the tail 5A will prevent the rocker 1 5 being turned in the clockwise direction beyond the centralised position of Figure 5. Thus the lock can be quickly and easily converted for use with either left-wing or right-wing doors simply by changing the position of the screws 25, instead of having to dismantle the lock housing as is usual in known locks.

The slot 1 9 has a straight upper edge 28, as seen in Figures 3 to 5, and its opposite edge has an arcuate central portion 29, which is concentric with the rocker pivotal axis, and flat end portions 30 parallel to the upper edge 28. The width of the slot 1 9 at its centre is just greater than the diameter of the rocker pin 14, and at its two ends is greater than at the centre, forming enlarged end portions of the slot.

The latching bolt 6 and guide plate 17 assembling can be retracted by rotation of the rocker 1 5 from the up-tilted position of Figure 3 to the down-tilted position of Figure 4, the rocker pin 14 bearing on the flat end portion 30 at one end of the slot 1 9 to effect this withdrawal by a camming action. Stops 31 in the housing limit the travel of the guide plate 1 7. Moreover, when the rocker 1 5 is turned into its centralised dead-centre position shown in Figure 5, along the axis of symmetry 24 of the guide plate 1 7, it will effectively block, i.e. deadlock the latch bolt 6 in its projecting latched position. In this blocking position the axis 24 passes through the centre of the pin 14 and through the pivot axis of the rocker 15, and the pin 14 is abutted against the straight upper edge 28 of the slot 19.

A locking plate 32 is slidably mounted on the guide plate 1 7 for limited relative sliding movement thereon in the direction parallel to the axis 24 and is spring-biassed in the direction away from the bolt 6 by one portion of a double spring.

The spring-loaded lock plate 32 is of T-shape and is formed with a re-entrant V-shaped edge 34 whose apex lies on the axis of symmetry 24, so that with the rocker in the blocking position of Figure 5, the rocker pin 14 will lie as a close fit in the narrow central portion of the slot 1 9, abutted against the apex portion of the V-shaped edge 34 of the spring-loaded locking plate 32 so that the latter will hold the rocker 1 5 biassed into that dead-centre position deadlocking the latch bolt in its projecting latched position.

The spring 33 is of the double-V shape shown.

Its end 33A bears against the fixed socket portion 4A in the housing 1, its larger coil 33B freely surrounds a bracket 35 bent up from the guide plate 17, its smaller coil 33C closely surrounds an anchorage post 36 fixed on the guide plate 17, and its other end 33D bears against the head 37 of a T-shaped end bracket bent up from the end of the locking plate 32 with its stem extending at right angles to the plate 32 through a slot 38 in the guide plate 1 7. Thus the spring 33 by reacting against the fixed anchorage 4A biasses the post 36 and with it the guide plate 1 7 and latch bolt 6 in the outward direction towards the latched position, whilst the end 32D of the spring biasses the locking plate 32 in the other direction relative to the guide plate 1 7.

The knob 3 on the inner face of the housing 1 is formed in two parts, namely a cup-shaped outer part 3A which is rigidly mounted on the rocker spring at 23 and has a serrated frusto-conical circumferential surface 29, and a coaxial inner push-button portion 3B which fits closely in the outer part 3A and can be depressed against the force of a helical spring 40. The push-button 3B is mounted on a coaxial spindle 41 which is rotatable and longitudinally slidable in an axial bore in the hub of the rocker 1 5, and which has a head 42 at its inner end. When the push-button 3B is depressed with the latch bolt 6 and guide plate 1 7 in the retracted position shown in Figure 4, the head 42 will enter the narrow central portion of the transverse slot 1 9 as a close fit therein, thus locking the latch bolt in the retracted position.Moreover, as the rocker pin 14 now lies against the flat 30 in the enlarged end portion of the slot 19, this allows the locking plate 32 to be moved by the spring end 33D along the guide plate 17 until the margin of the V-shaped edge 34 of the spring-loaded locking plate 32 engages behind the head 42 of the spindle 41, thus locking the spindle and the knob 38 in the depressed position holding the bolt 6 locked in its retracted position.When the rocker 1 5 is next turned by rotation of the knob portion 3A in the "latching" direction, anticlockwise in Figure 4, the pin 14 will lift the locking plate 32 to allow the spindle 41 to be retracted by the spring 40 until the head 42 is clear of the slot 19 in the guide plate and underlies the apex of the V-shaped edge portion 34 of the locking plate 32, thus freeing the guide plate 17 for return movement to the latching position of the bolt under the force of the spring 33.

The operation of the lock described and illustrated will now be briefly described. Assume that the lock is initially in the "latched" position shown in Figure 3, with the latch bolt 6 protruding into the keeper 5 to prevent the door being opened. If it is required to deadlock the latch bolt from inside the door, the outer portion 3A of the knob 3 is rotated manually in the direction to turn the rocker 1 5 from its position in Figure 4 into its dead-centre position of Figure 5 in which it blocks the guide plate 1 7 and latch bolt 6 against movement in either direction. The edge 14 of the spring-loaded locking plate 32 now holds the rocker in its blocking position.

To unlock and release the latch, the outer knob portion 3A is rotated in the opposite direction to turn the rocker 1 5 back into the tilted position of Figure 3, the pin 14 camming back the locking plate 32 against the force of the spring end 33D, to allow the pin to travel above the arcuate edge portion 29 of the slot, into the enlarged end portion thereof. Further rotation of the knob portion 3A turns the rocker into the position of Figure 4 and retracts the lock bolt 6 from the keeper 5.

If it is desired to lock the latch in this retracted position, the central push-button 38 of the knob 3 is now depressed to advance the head 42 of its spindle 41 into the narrow central portion of the slot 19, thus locking the guide plate 17, and the spring-loaded locking plate 32 engages behind the head 42 to hold the push-button in that depressed locking position. As already described, the pushbutton can be freed by rotation of the outer knob portion 3A in the reverse direction to cause the rocker pin 14 to lift the locking plate 32 clear of the head 42, when the spring 40 will retract the spindle 41 and the spring 33 will move the guide plate 1 7 and latch bolt 6 into the protruding latching position.

It will be understood that it is also possible to deadlock the latch bolt 6, and to release and retract it from the keeper by corresponding turning movements of a key inserted from outside the door into the cylinder lock. It is not possible however to lock the latch in its retracted position by the use of the key, although it is possible to release the locking spindle 41 of the depressed pushbutton 38 by means of the key to unlock the retracted latch.

It will also be understood that if the lock is mounted with the stop screw 25 inserted into the hole 27 and socket 27', the operation of the locking mechanism will take place as described above except that the rocker 1 5 will be turned by the knob or key so that its spindle travels above the left-hand half of the guide plate slot 1 9, instead of along the right-hand slot into which its entry is prevented by the engagement of the rocker tail 15A against the screw 25.

Claims (23)

1. A door lock with a lockable linearly-moving latch bolt having an operating member by which all the operating actions of the lock can be performed from inside the associated door when in use, the operating member comprising a knob having a first part in the form of an outer body and a relatively-movable second part surrounded by the outer body.

2. A door lock with a lockable linearly-moving latch bolt, having a single operating member by which all the operating actions of the lock can be performed from inside the associated door when in use, the single operating member comprising a rotatable first part and a linearly-movable second part, the first and second parts together forming the complete member.

3. A door lock as claimed in Claim 1 or Claim 2, in which the said first part coaxially surrounds the said second part.

4. A door lock as claimed in any one of the preceding claims, in which the retraction of the latch bolt against the force of a latch spring is performed by rotation of the said first part of the knob.

5. A door lock as claimed in any one of Claims 1 to 4, including locking means for locking the latch bolt tn the retracted pos;t;on, the locking means being constructed and arranged to be operated by depression of the said second part of the knob.

6. A door lock as claimed in Claims 4 and 5, in which the said locking means is arranged to be released, to unlock the retracted latch bolt, by rotation of the said first part of the knob in the opposite direction to that required in retraction of the latch bolt.

7. A door lock as claimed in Claim 5 or Claim 6, in which the said locking means comprises a locking shaft secured to the second part of the knob and longitudinally movable therewith transversely to the direction of movement of the latch bolt, the shaft having a head arranged to engage with an abutment surface on the latch bolt or a part rigidly secured thereto, to lock the bolt in its retracted position, when the second knob part is depressed.

8. A door lock as claimed in Claim 7 in which the abutment surface comprises an edge of a slot formed in a guide plate rigidly secured to the latch bolt for movement therewith, the head of the locking shaft entering the slot when the second knob part is depressed.

9. A door lock as claimed in Claim 8 which includes a return spring acting on the second knob part to tend to return it from its depressed position, and a spring-loaded detent member arranged to move in engagement behind the head of the locking shaft when the head enters the slot and to prevent the withdrawal of the head from its locking engagement in the slot until the detent member is lifted against its biassing spring.

10. A door lock as claimed in Claims 6 and 9, in which the rotation of the first part of the knob in the said opposite direction is arranged to lift the detent member and release the said locking means.

11. A door lock as claimed in Claim 9 or Claim 10, in which the spring-loaded detent comprises a locking plate slidably mounted on the guide plate and acted on by a biassing spring.

12. A door lock as claimed in any one of the preceding claims, which includes second locking means operable to deadlock the latch bolt in its latched position.

13. A door lock as claimed in Claim 4 and Claim 12, in which the second locking means is operated by rotation of the said first part of the knob in the opposite direction to that required for retraction of the latch bolt, and is released by rotation of the said first part in the same direction as required for retraction of the latch bolt and prior to retraction.

14. A door lock as claimed in Claim 8, which includes a pivotally-mounted rocker having an eccentric pin engaged in the slot in the guide plate and coupled to the said first part of the knob for rotation therewith whereby rotation of the first part of the knob is transformed by the pin and slot connection into linear retraction movement of the guide plate and latch bolt assembly.

1 5. A door lock as claimed in Claims 12, 1 3 and 14 in which the seeker in rotatable into a dead-centre position with respect to the guide plate, in which position by the engagement of its eccentric pin in the slot it deadlocks the latchbolt in the latched position.

1 6. A door lock as claimed in Claims 11 and 15 in which the spring-loaded locking plate is arranged to bear resiliently at one edge against the eccentric pin of the rocker when the latter is in its dead-centre dead locking position, that edge of the locking plate being formed with a recess in which the pin is then engaged whereby the locking plate resiliently locates the rockers in its dead-centre position.

17. A door lock as claimed in any one of Claims 14 to 16, in which the slot is symmetrical about its transverse axis and in which when the rocker is in its dead-centre position its eccentric pin is engaged in the central portion of the length of the slot, and which includes a stop member removably mounted in a selected one of two positions in each of which it prevents rotation of the rocker in a respective angular direction out of its deadcentre position, and allows the pin to travel only along one or other of the two halves of the length of the slot depending upon the position in which the pin is fixed, whereby the lock can be preset for use with either a right-hand-hinged or a left-handhinged door by the selective positioning of the stop member.

18. A lock as claimed in Claim 17, in which the stop member comprises a stop screw selectively insertable into one or other of the two spaced holes in a housing of the lock, and in which the rocker has a tail portion one or other of whose opposite sides engages the screw when in the respective hole to prevent rotation of the rocker out of the dead-centre position in the respective angular direction.

19. A lock as claimed in Claim 18 in which the stop screw can be removed from one hole and inserted in the other without opening the housing of the lock, the housing containing the operating mechanism of the lock.

20. A lock as claimed in any one of the preceding claims, constructed and arranged to be operated additionally from outside the associated door by means of a key inserted in an associated cylinder lock, the dead-locking and release of the latch bolt and the retraction of the bolt being effected by appropriate rotation of the key.

21. A lock as claimed in Claim 20 when dependent on any one of Claims 14 to 1 9, including a rotatable bush journalled in the lock on the side which in use will be applied to the associated door, the bush being coupled coaxially to the rocker for rotating the latter and being adapted to be coupled to a rotary part of the associated cylinder lock for rotation by the key.

22. A lock as claimed in Claim 21, in which the coupling between the bush and the rocker comprises a disc coaxially secured to the bush and formed with a radial slot in which the outer end of the eccentric pin of the rocker is engaged.

23. A door lock with a lockable latch, substantially as specifically described herein with reference to the accompanying drawings.