GB2322902A - Latch and deadbolt locksets - Google Patents

Abstract

A lockset for a door (D) comprises a cylinder mortice sash lock (L), a locking cylinder (17) for the sashlock comprising a rotatable thrower (13) to extend or retract the dead bolt (8) of the sashlock, a tumbler mechanism in one end of the cylinder to turn the thrower by key operation from outside the door, and a rotatable plug (33) in the other end of the cylinder to turn the thrower from inside the door without a key. An operating assembly fitted to the inside face of the door comprises a handle (23), a first rotary transmission member(27) adapted to be linked to the plug (33), a second rotary transmission member (28) adapted to be linked to the latch bolt (3) of the sashlock, and a mechanism providing lost motion, so that turning the handle through 90‹ above the horizontal extends and retracts the dead bolt without retracting the latch bolt, while turning the handle downwards below the horizontal retracts the latch bolt.

Description

Locksets The present invention relates to locksets and more particularly to locksets incorporating so-called cylinder mortice sashlocks.

By "cylinder mortice sashlock" we mean a lock of the well-known kind comprising a casing adapted to be mounted into an aperture in a door edge and bearing both a latch bolt and a dead bolt. The latch bolt is spring-biased to extend its head from the casing, the bolt head being bevelled or otherwise shaped to permit slam closure of the door. A follower within the casing retracts the latch bolt when the follower is turned through a specified angle in a specified sense of direction, the follower being configured to receive a spindle from one or more handles mounted to the door. The dead bolt is configured to be extended and retracted by the turning through a specified angle in opposite senses of a thrower which forms part of a locking cylinder mounted transversely through the casing. In the normal arrangement the latch bolt follower is coupled to be turned by respective handles mounted on each side of the door, and the dead bolt thrower is adapted to be turned by key operation from each side of the door, the locking cylinder thus comprising a respective tumbler mechanism in each of its ends. Where a so-called "nightlatch" function is provided, the outside handle is omitted and a linkage is provided within the casing to permit retraction of the spring bolt from the outside by means of an additional rotation of the dead bolt thrower with the key. In another variant, the locking cylinder comprises a tumbler mechanism in one end only, thus requiring key-operation only from the outside of the door, while its other end comprises a thumb turn to enable manual rotation of the dead bolt thrower from the inside. In the first two cases above, opening of the door from either side from its fully locked condition is impossible without a key. In the third case a key is not required on the inside, but the user must perform two separate manipulations (of the dead bolt thumbturn and the latch bolt handle) to open the door.

The present invention seeks to provide a lockset in which a cylinder mortice sashlock is adapted to provide an "escape" or "anti-panic" function - that is to say where both bolts can be retracted from the inside by the manipulation of a single operating member and without the need of a key. Such a function is essential for locks fitted to emergency exit doors, to permit rapid egress of the region closed by the door in the case of fire or other emergency while still preventing unauthorised entry into that region. Locksets according to the invention may, however, be used more generally, for example on the doors of flats (apartments) or other dwellings where handle-only operation from the inside is chosen for convenience without prejudice to the security afforded by key-operation from the outside.

The invention accordingly resides in a lockset for a door comprising: a cylinder mortice sashlock; a locking cylinder for the sashlock, comprising a rotatable thrower adapted to extend and retract the dead bolt of the lock, a tumbler mechanism in one end of the cylinder whereby said thrower can be turned by means of a proper key from the outside of the door, and a rotary transmission member in the other end of the cylinder through which said thrower can be turned from the inside of the door without a key; and an operating assembly adapted to be attached to the inside face of the door, comprising a handle or the like operating member, a first rotary transmission member adapted to be linked to the aforesaid rotary transmission member of the cylinder, a second rotary transmission member adapted to be linked to the latch bolt follower of the lock, and mechanism within said assembly whereby turning of said operating member in opposite senses through a first specified angle is effective to turn said first rotary transmission member in opposite senses through a specified angle to extend and retract the dead bolt of the lock but without turning said second rotary transmission member, and turning of said operating member in a specified sense through a second specified angle beyond the first is effective to turn said second rotary transmission member in a specified sense through a specified angle to retract the latch bolt of the lock.

The invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: Figure 1 illustrates one embodiment of a sash lock which may be used with the invention, with its cap removed; Figure 2 is a partial section through a preferred embodiment of lockset according to the invention as fitted to a door; Figure 3 shows part of the operating mechanism within the inside furniture plate of Figure 2, when the dead bolt is extended; Figure 4 is a view similar to Figure 3 when the dead bolt is retracted; Figure 5 is a view similar to Figures 3 and 4, when the latch bolt is retracted; Figure 6 shows the exterior of the furniture plate of Figures 3 to 5; and Figure 7 illustrates two different forms of locking cylinder which may be used with this embodiment of the invention.

Referring to Figure 1, this illustrates the internal mechanism of one known form of cylinder mortice sash lock L with which the invention may be used. It comprises a case 1 normally closed by a cap (not shown) and having an attached forend 2. A latch bolt 3 is borne for extension and retraction in an upper part of the case 1, being biased to its extended position by a spring 4.

The head 3A of the latch bolt is bevelled as usual to permit slam closing of the door in conjunction with an associated striking plate (not shown). A follower 5 is borne within the case and linked to the latch bolt 3 to retract the same when the follower is turned through approximately 450 in the clockwise sense as viewed in Figure 1, the follower having a square-sectioned hole 5A by which it is adapted to be linked to a spindle from internal and external handles (not shown in Figure 1).

A separate spring 6 biases the follower 5 to its illustrated rest position, against a stump 7 which also serves as a guide for the tail of the latch bolt and to receive a cap fixing screw.

A dead bolt 8 is borne for extension and retraction in a lower part of the case 2, being shown retracted in Figure 1. A detainer 9 for the dead bolt is borne for movement at right angles thereto, being guided by a stump 10 which also serves as a guide for the tail of the dead bolt, and by a stump 11 which also receives a cap fixing screw.

The detainer 9 is biased to its illustrated rest position by another leg of the spring 4, and serves to detain the dead bolt by means of a stump 8A on the latter engaging in one of two pockets of a racking slot 9A in the detainer depending on whether the dead bolt is extended or retracted. For extending and retracting the dead bolt a locking cylinder (not shown in Figure 1) is received transversely through apertures 1A in the case and cap and fixed in position by a set screw 12, the cylinder having a rotatable thrower notionally indicated at 13 in Figure 1. In order to extend the deadbolt 8 from its illustrated position the thrower 13 is turned through approximately 1800 in the anticlockwise sense as viewed in Figure 1. In so doing it lifts the detainer 9 to free the stump 8A for forward movement, and then engages in a drive slot 8B in the tail of the dead bolt to extend the same, finally releasing the detainer to fall with the stump 8A trapped in the forward pocket of the racking slot 9A. Retraction of the dead bolt is the reverse of this process, with the cylinder thrower 13 being turned back 1800 to its position shown in Figure 1.

Figure 2 illustrates a lockset in accordance with the invention as fitted to a door D, the position of the sash lock L of Figure 1 being indicated in phantom. To the outside face of the door is fitted a furniture plate 14 bearing a lever handle 15 on a fixed rose 14A. The handle 15 is connected through a spindle 16 to the follower 5 of Figure 1, and is normally held in a horizontal position by the action of the follower spring 6. Depressing the handle 15 from this position through approximately 45" therefore retracts the latch bolt 3 in conventional fashion. A locking cylinder 17 incorporating the thrower 13 and fitted to the lock L in the manner described above is also seen in Figure 2.

That part of the cylinder 17 which is directed towards the outside face of the door incorporates a rotatable plug 18 which is normally blocked against rotation by a conventional tumbler mechanism of which details are not shown. That part of the cylinder 17 which is directed towards the inside face of the door incorporates a second rotatable plug 33 with no associated tumbler mechanism and which is permanently coupled to the thrower 13.

Insertion of a correct key from the outside of the door into the keyway 18A of the cylinder plug 18 frees that plug for rotation, and the tip of the key also presses in a coupling 19 against the bias of a spring 20 to connect the plug 18 to the plug 33. With the key thus inserted, rotation of the plug 18 in either sense is effective to turn the thrower 13 via the plug 33 in a corresponding direction to extend or retract the deadbolt 8 accordingly. In this respect, the transmission between the plug 18 and thrower 13 will provide sufficient lost motion that the usual 3600 rotation of the key 8 turns the thrower 13 through only the 1800 required to shift the bolt.

To the inside face of the door D is fitted a furniture plate 21, being fixed in place by set screws 22 passing through the door into threaded bosses 14B on the outside plate 14. The plate 21 incorporates an operating mechanism for both bolts of the lock L in accordance with the invention, components of which are also seen in different phases of operation (and with the position of the thrower 13 superimposed) in Figures 3 to 5.

The plate 21 bears a lever handle 23. The handle 23 is fastened by a pin 24 to a rotatable boss and rose assembly 25A,25B,25C on which are keyed a stop plate 26 and gear plate 27. An inner boss 28 is mounted coaxially within the member 25B, with lost motion therebetween as described hereinafter, and receives the end of the latch bolt spindle 16. The gear plate 27 meshes with an intermediate cog 29 (Figures 3 to 5) which in turn meshes with a pinion 30. For a reason to be described hereinafter the pinion is connected through a so-called Oldham's coupling 31 to a rectangular-sectioned drive member 32. The drive member 32 is received in a complementary socket 33A in the rotatable plug 33. For a reason to be described hereinafter, the plug 33 is also slidable through a limited distance within the cylinder 17 but is normally biased to the illustrated position by a spring 34 (being stiffer than the spring 20). In all axial positions, however, the plug 33 is coupled to transmit rotation directly to the thrower 13. A fixed peg 35 extends from the inside furniture plate assembly into a bore 36 in the cylinder 17 to assist in the correct relative location of these components.

Figure 3 illustrates the position of the operating mechanism within the furniture plate 21 in the fully locked condition of the door D, i.e. with both bolts 3 and 8 of the lock L extended. In this condition the handle 23 is oriented vertically and prevented from turning in one direction by a peg 37 in the path of the stop plate 26. The peg 37 is mounted on a fixed plate 37A (Figure 2) the position of which can be changed to reverse the "hand" of the furniture. The handle 23 is also yieldably detained against turning in the opposite direction in Figure 3 by a detent plate 38 biased by a spring 39 against a lobe 26A of the stop plate. To retract the dead bolt 8 of the lock from the inside, the handle is turned through approximately 900 from the position of Figure 3 to the position of Figure 4, in which the handle is yieldably detained in a horizontal orientation by the detent plate 38 acting against another lobe 26B of the stop plate. Turning the handle 23 through this angle in this direction drives the gear train 27/29/30 to turn the drive member 32 through a 1:2 ratio in the same sense. The drive member 32 accordingly turns the plug 33 and thereby the thrower 13 through 1800 to retract the dead bolt 8 as described above with reference to Figure 1. Returning the handle 23 to the vertical from this position drives the mechanism in the opposite sense to correspondingly extend the dead bolt 8.

As will be appreciated from Figures 3 and 4, in turning the handle 23 between the horizontal and vertical positions to extend or retract the dead bolt 8 there is lost motion between the members 25B and 28 so that the latter remains stationary under the bias applied to the latch bolt follower 5. In other words, use of the inside handle 23 to operate the dead bolt 8 in either sense does not cause any movement of the spindle 16, outside handle 15 or latch bolt 3. Neither is there any effect on the plug 18 which remains locked in the cylinder 17 and disconnected from the thrower 13.

Assuming now that the inside handle 23 is in the horizontal position of Figure 4 (i.e. with the dead bolt 8 retracted but the latch bolt 3 still extended), further depression of that handle through approximately 450, to the position of Figure 5 in which the handle is again stopped by engagement of the plate 26 with the peg 37, causes the member 25B to turn the inner boss 28. The spindle 16 is thereby turned to retract the latch bolt as described above with reference to Figure 1. During this movement the thrower 13 will also be turned through the gear train and plug 33 to the downward position shown in Figure 5. This movement of the thrower occurs in free space, however, so has no effect on the dead bolt 8.

It will thus be appreciated that the operation of the sash lock L from the outside is conventional, with the handle 15 operating the latch bolt and a key in cylinder 17 operating the dead bolt. Operation from the inside is solely by means of the handle 23, however, with movement between the horizontal and vertical operating the dead bolt and movement below the horizontal operating the latch bolt. Latch bolt operation from the outside does not have any effect on the inside handle 23 by virtue of the lost motion between members 28 and 25B.

Dead bolt operation from the outside does, however, result in corresponding movement of the handle 23 by virtue of its permanent linkage through to the thrower.

Thus whenever the key is used to extend the deadbolt the handle is driven by the plug 33 through a 2:1 reduction ratio from the Figure 4 position to the Figure 3 position and vice versa. The position of the handle 23 therefore represents at any time whether the dead bolt is extended or retracted, irrespective of from which side of the door it was last operated. If desired, however, an additional status indicator may be incorporated as shown in Figure 6. Thus the pinion 30 may be marked with two coloured fields visible through a window 40A in a fitment 40 on the furniture plate 21, red showing when the door is locked and green when it is only latched.

Operation of the lockset is "failsafe", in the sense that no misalignment of the operating mechanism from either side of the door will prevent authorised entry or exit.

For example, if the inside handle 23 is inadvertently left in an intermediate position between the vertical and horizontal, the plug 3 (and thrower 13) will be partially turned so as to be misaligned with the coupling 19.

Upon insertion of a key into plug 18, however, the coupling 19 will be pressed against the end of plug 33 to displace the latter against its spring 34. The plug 18 is still free to turn, therefore, and when the coupling 19 reaches the angular position of the plug 33 the latter will snap back into engagement with the coupling to complete the requisite shifting of the dead bolt. If a key is inadvertently left in the plug 18 with the coupling 19 engaged with the plug 33 in any rotary position, this will not impede operation from the inside in any way because of the permanent drive train between the handle 23 and thrower 13.

Figure 7 shows two different types of locking cylinder with which the same operating mechanism within the furniture plate 21 may be used. Figure 7A depicts a cylinder 27 of Europrofile form as shown also in Figure 2 and for which the lock case is shown prepared in Figure 1. Figure 7B depicts a cylinder 17 of oval form which is functionally equivalent to cylinder 17 but which when mounted in a suitable lock case has the axis of its socket 33A' for the drive member 32 offset by the dimension d from where the axis of the corresponding socket 33A of cylinder 17 would be. It is for this reason that the Oldhams coupling 31 is incorporated, as it permits the rotational axis of the drive member 32 to be altered relative to that of the pinion 30 by a certain dimension without affecting the transmission of rotation between them.

The method of fitting the illustrated embodiment of lockset to the door D is as follows. The door is prepared as necessary and the lock L and cylinder 17 are installed in conventional fashion. The outside furniture plate and rose 14/14A are fitted, and the spindle 16 is fed from the inside through the follower 5 and plate 14 until a stop 16A on the spindle abuts the exterior of the lock case 1. The outside handle 15 is then fitted to the spindle 16 and secured by a grub screw 15A. The dead bolt 8 is extended with the key and the plug 33 is manipulated if necessary to bring its socket 33A horizontal. The inside furniture plate 21, already assembled with its handle 23 and operating mechanism, is taken, the plate 37A is set to give the desired "hand", the handle 23 is set to the deadlocked (vertical) position and the spindle boss 28 is centralised. That assembly is then presented to the door so that the spindle 16 locates in the boss 28, the drive member 32 locates in the socket 33A and the peg 35 locates in the bore 36, and the furniture plate 21 is clamped to the door by means of the screws 22 into the furniture plate 14. Figure 2 shows this lockset as fitted to a relatively thick door, from which there is no protrusion of the cylinder 17 on the inside. The couplings between the parts 16/28, 32/33A and 35/36 permit a range of door thicknesses to be accommodated, however, the respective depths of insertion between these components increasing with doors thinner than illustrated.

Claims (8)

1. A lockset for a door comprising: a cylinder mortice sash lock; a locking cylinder for the sash lock, comprising a rotatable thrower adapted to extend and retract the dead bolt of the lock, a tumbler mechanism in one end of the cylinder whereby said thrower can be turned by means of a proper key from the outside of the door, and a rotary transmission member in the other end of the cylinder through which said thrower can be turned from the inside of the door without a key; and an operating assembly adapted to be attached to the inside face of the door, comprising an operating member, a first rotary transmission member adapted to be linked to the aforesaid rotary transmission member of the cylinder, a second rotary transmission member adapted to be linked to the latch bolt follower of the lock, and mechanism within said assembly whereby turning of said operating member in opposite senses through a first specified angle is effective to turn said first rotary transmission member in opposite senses through a specified angle to extend and retract the dead bolt of the lock but without turning said second rotary transmission member, and turning of said operating member in a specified sense through a second specified angle beyond the first is effective to turn said second rotary transmission member in a specified sense through a specified angle to retract the latch bolt of the lock.

2. A lockset according to Claim 1 wherein said operating assembly includes a gear train between said operating member and first rotary transmission member arranged such that turning said operating member through said first specified angle is effective to turn said first rotary transmission member through an angle greater than said first specified angle.

3. A lockset according to Claim 1 or Claim 2 wherein said first rotary transmission member is associated with coupling means whereby the position of the rotational axis thereof is adjustable within said operating assembly.

4. A lockset according to any preceding claim wherein said second rotary transmission member is coaxial with the axis upon which said operating member turns, and the axis of said first rotary transmission number is parallel thereto.

5. A lockset according to Claim 4 wherein said second rotary transmission member is borne coaxially within an intermediate rotary transmission member through which motion is transmitted from said operating member to said first rotary transmission member, there being lost motion between said intermediate and second rotary transmission members.

6. A lockset according to any preceding claim wherein said rotary transmission member of the cylinder is permanently linked to transmit rotation to said thrower and said cylinder includes a key-releasable plug in said one end thereof and a coupling member adapted to transmit rotation from said plug to said rotary transmission member when a proper key is inserted into said plug.

7. A lockset substantially as hereinbefore described with reference to the accompanying drawings.

8. An aforesaid operating assembly for use in a lockset according to any preceding claim.