AU3353689A - A door lock - Google Patents

Description

A DOOR LOCK Background of the Invention .

This invention relates to door locks and in particular relates to key and cylinder lock sets that are adaptable to suit a range of applications.

The lock of this invention has been defined to conform in general, to the requirements specified by the U.S. Hardware Manufacturers Association Standard No. A156.2-1983. To fulfil the requirements of this Standard the lock must be able to carry out a large variety of functions depending on the environment in which.the lock is used. Discussion of Prior Art

Most cylindrical lock sets have a latch which extends about 1/2 inch from the front of the lock-. It is well known to add a deadbolt that extends considerably further into the door jamb to provide a deadlocking feature. The deadlock is often actuated by the keyed cylinders that are positioned in each handle- Sometimes the deadlock bolt is actuated by a reverse turn of the handle. The 1 inch throw of the deadlocking bolt gives the door a considerably higher security rating since it becomes virtually impossible to lever the door open. Furthermore, in the case of fire where the door and door jamb may distort, the 1 inch throw of the deadbolt normally ensures that the door remains locked. A problem with using an auxiliary deadbolt is that an additional lock mechanism and fitting is required with the necessity to provide an extra hole in the door jamb. It has thus been proposed to provide key and cylinder cylindrical lock sets that include a locking bolt that is displaceable from three positions, namely a fully retracted position to a latching position whereby the locking bolt extends from the lock case to approximately 1/2 inch to a fully extending deadlock position in which the locking bolt extends 1 inch from the lock. Examples of this type of lock can be seen from U.S. Patents

4,255,953 and 4,594,864. As can be seen from U.S. Patent 4,594,864 it has also been proposed to provide either keyed cylinders in each handle or a keyed cylinder in one handle with a turn screw in the opposite handle. The keyed cylinder or turn screws are interconnected by a spindle.

The lock of the present invention has been designed to provide a wide variety of features while still using the same basic lock configuration. It is the aim of the present invention to provide an assembly that can be simply- adapted by the removal or addition of an extra component to provide any of the functions designated by the applicable U.S. standard. The same lock can be used to provide the full sophistication of a high security lock to the simpler, effective and easy-to-use locks that would be used in, for instance, a conventional bathroom door.

Summary of the Invention

According to the present invention there is provided a door lock comprising a locking bolt assembly coupled to a handle assembly positioned on one side of the door; the handle assembly including a rotatable handle, a drive shaft and a clutch to selectively engage or disengage drive from the handle to the drive shaft; actuating means positioned on the other side of the door operable to actuate the clutch by a spindle connected therebetween; and a drive mechanism driven by said handle assembly to cause a locking bolt of the locking bolt assembly to move between a partially extended latching position, an extended deadlocked position and a retracted position, the drive mechanism including a crank pivotally secured to a connecting arm to impart linear movement to the bolt. According to a further aspect of the present invention there is provided a door lock comprising a pair of handle assemblies arranged to be positioned coaxially one on each side of a door, a locking bolt assembly located within the door, a drive mechanism interconnected to the handle assemblies, whereby each handle assembly provides independent drive to the drive mechanism, the drive mechanism being operable to cause a locking bolt of the locking bolt assembly to move between a partially extended latching position, an extended deadlocked position and a retracted position, each handle assembly including a locking actuating means coupled to a clutch; a spindle interconnecting the locking actuating means of both handle assemblies, whereby actuation of the clutch causes disconnection of the drive from either handle to the drive mechanism, the drive mechanism including a crank that allows the locking bolt to assume a deadlocked position with the crank over-centre when in the extended position.

Description of the Drawings Various embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a plan view of a lockset assembly showing it mounted in a steel door; Figure 2 is a cross-sectional view along the lines XX in Figure 3;

Figure 3 is a horizontal exploded plan view showing the various subassemblies of the lockset assembly; Figure 4 is a perspective exploded view of one half of the actuating hub assembly;

Figure 5 is a schematic view of the hub with a slide at one extremity;

Figure 6 is a schematic view of the hub with the slide fully forward at the other extremity;

Figure 7 is a plan view of a lock bolt assembly when in the fully extended deadlocked position;

Figure 8 is a side view of the lock bolt assembly when in the fully extended deadlocked position and a flap in a position corresponding to an unlocked clutch in the exterior handle assembly;

Figure 9 is a side view of the lock bolt assembly when in the fully extended deadlocked position with the flap rotated to the position corresponding to a locked clutch in the exterior handle assembly; Figure 10 is a plan view of the lock bolt assembly when in the latching position;

Figure 11 is a plan view of the lock bolt assembly in the unlatched position with the bolt fully withdrawn;

Figure 12 is a side view of the lock bolt assembly when fully retracted as Figure 11;

Figure 13 is an exploded view of the components of the lock bolt assembly; Figure 14 is an exploded view of the internal components of a handle assembly;

Figure 15 is a cross-sectional view of the handle assembly;

Figure 16 is a cross-sectional view taken along the lines 16-16 of Figure 15;

Figure 17 is a cross-sectional view taken along the lines 17-17 of Figure 15;

Figure 18 is a cross-sectional view taken along the lines 18-18 of Figure 15; Figure 19 is a plan view of a tail type 1;

Figure 20 is a plan view of a tail type 2;

Figure 21 is a plan view of a washer used in conjunction with a tail type 2;

Figure 22 is a plan view of a recess in tail extension type 1;

Figure 23 is a plan view of a recess in tail type 2; and

Figures 24 to 39 illustrate schematically the various functions of the lock when used in different roles. Detailed Description

Referring to the Figures 1 to 23 and in particular to Figures 1 to 3 a locking bolt assembly 2 and central hub 3 are mounted within a door 4 while an exterior handle assembly 5 and its lever extension 6 and interior handle assembly 7 and its lever extension 8 are mounted on the faces of the door with, as is customary, the hand operated levers 6 and 8 extending horizontally. The exterior and interior levers are used to retract a locking bolt 2a from a strike plate 9 mounted on the door jamb 10. The exterior handle assembly 5 may be provided with a removeable core 20 mounted in a recess 21 and the interior handle assembly 7 may also be provided with a removeable core 22 which locates in a recess 23. The cores may take the form of a keyed locking cylinders or a thumbturn or a coin slotted turn depending on the function of the lock. For an entry lock the exterior lever has a keyed core while the interior lever has a thumb turn and each of these can be used to lock the exterior lever and disengage a clutch-in the exterior handle assembly 5 thereby disengaging the exterior lever from its drive shaft 24. A drive shaft 25 of the interior lever 7 usually transmits lever torque to the meshing hub member 3 at all times. Figure 3 shows the exterior handle assembly 5 rotatably mounted in a rose 30 while interior handle assembly 7 is rotatably mounted in rose 31. These roses 30 and 31 are threadably fastened together by screws 33 which pass through the periphery of the hub 3 thereby preventing relative rotation between the hub and roses. The latch bolt assembly 2 is located in a slot 34 in the hub 3 by a fastener 35 which may take the form of a screw. The roses have inwardly pointing tabs 36 (Figure 1) which locate in slots in steel doors to prevent rotation of the roses relative to the door. A spindle 40 rotationally couples the cores of the handle assemblies. Splined drive shafts 24 and 25 are rotationally coupled to actuating members 41 and 42 respectively which are rotationally mounted within the hub 3. The splined engagement accommodates various door thicknesses since rotational motion is conveyed irrespective of the length -of splined engagement.

Figures 2 and 4 illustrate details of the hub 3 which includes means to impart drive to either side of the bolt assembly 2. Since both sides are identical only one is described here with reference to Figures 2 and 4. The actuating member 41 is rotatably mounted within the hub said member being a disclike plate with a V-shaped wedge 45 protruding from an interior face to fit within a mating slot 42 in a slide plate 50, the slot 42 having the shape of a two dimensional funnel with lead-ins 43 and 44 each having a cam follower surface 46 adapted to be engaged by the V-shaped wedge 45 of the actuating member. The exterior face of the actuating member takes the form of a round cylindrical boss 48 (Figure 2) with an internally splined aperture 49 to mate with the splined drive shaft 24 of the handle assembly.

The slide plate 50 is constrained for linear movement in a direction of bolt movement by a pair of parallel spaced apart rails 51 formed on the interior of the hub case 3a. The face of the plate 50 adjacent the lock bolt assembly 2 is provided with a substantially rectangular projection 53 having a central elongate slot 54 through which the spindle 40 freely extends and an elongate recess 35a to accommodate the screw 35 (Figure 3). The end of the projection 53 nearest the bolt is provided with a squared projection that defines shoulders 57a and 57b. The opposite end has a T-shaped projection that also defines shoulders 58a and 58b with either side of the walls of the rectangular projection 53. The shoulders 58a and 57a engage a pin 78 and 79 respectively that projects from a rack 77 forming part of the actuating mechanism. The location of the shoulders is such that linear movement of the plate towards the bolt drives the rack yet return of the rack does not drive the plate 50. The other shoulders 57b and 58b allow the 5 assembly to be used with a door of reverse hand where the lock bolt assembly 2 will be reversed with the pins 78 and 79 adjacent the upper surface and not in the lower position as shown in Figure 4.

Each side of the hub 3 is identical so that 0 rotation of either actuating means in either direction causes at least one slide 50 to move in a direction parallel to bolt movement and towards the bolt end of the hub 3.

In Figure 5 the hub components are shown 5 schematically in the configuration where the slide 50 is fully biased back by a spring force and where the actuating member 41 is in its unrotated position while in Figure 6 the slide 50 is shown driven fully forward by rotation of the actuating member 41 as would correspond 20 to a bolt being fully withdrawn.

Referring to Figures 7 to 13 the latch bolt assembly 2 is shown in its various positions. The assembly includes a latch case 61 having two parallel - spaced latch plates 67 and 68 extending rearwardly from 25 it. The latch plates are held mounted spaced apart by means of a bush 82 and by hook like protrusions which connect the plates to the case 61.

A crank 93 is rotationally mounted between the plates via protruding bosses 94 integral with the crank 30 93 that locate within holes 97 in the plates. The crank 93 meshes with a geared rack 77 Which is constrained and guided by two pins 78 and 79 which are fastened the rack and which pass through two elongated slots 80 and 81 in the adjacent plates 47 & 68 whereby defined limited 35 linear movement of the rack is accommodated. The crank 93 is connected to a connecting arm 66 via a pivot point 96 and the other end of the connecting arm locates freely in an elongated slot 100 (Figure 3) in the rear of the main bolt and it connects pivotally to the bolt by a pin 63 which locates in a circular recess in the walls of the slot and which passes through a circular hole in the arm 66. The pin is also provided with an axial bore in which locates a spring 64 and ball 65. In one end of the slot 100 is a spring recess 98 locates an auxiliary spring 70 and a ? cylindrical pin 71 which provides a spring force to the end 72 of the arm to exert a tongue which tends to drive the arm and crank over-centre when the bolt is fully extended thereby effecting deadlocking. Deadlocking is further ensured by a protrusion 74 near the pivot 96 which, at deadlocking, locates behind a ledge 75 in the rear of the bolt case 61. During fire or other abuse where the lever and hub assemblies and rack and crank may be destroyed, the bolt will be maintained deadlocked. The drive from the handles to the bolt includes conversion of a rotating drive of the drive shaft 24 to a linear drive of the slide 50 to the rack 77 that imparts rotary movement to the crank 93 that is finally translated into linear movement of the bolt 60 by the connecting arm 66, this drive mechanism provides a stepped up gearing of approximately 2:1.

The bolt components are illustrated in detailed in Figure 13. The main bolt 60 is of circular cross-section but has a flat side 80 opposite the tapered latch portion 81. An auxiliary bolt 82 is a sliding fit on the flattened side 80. The auxiliary bolt 82 has a central longitudinal slot 10 and a pair of shoulders 108 at the inner end. The shoulders 108 engage similar abutments 84 on the flat part 81 of the bolt 60 to prevent movement of the auxiliary bolt 82 outward of the main bolt. The opposite or other end of the auxiliary bolt is stepped down at 104 to define a trigger latch 85. Although not shown, the apertures in the front of the bolt case 62 is such that the trigger latch 85 can project outwardly of the aperture with the stepped shoulders 104 engaging the aperture to prevent further outward movement. The underside of the auxiliary bolt has a transverse slot 110 of semi-circular cross-section that crosses the longitudinal slot 101. The main bolt 60 includes a transverse slot 100 into which the end of the connecting arm is pivotally supported by the pin 63. The side of the main bolt opposite to the flat side 80 has a longitudinal recess 86 into which the main spring 73 is located, the main spring 73 acting to urge the bolt 60 outwards of the casing. As shown in Figure 7 the main spring 73 extends rearwardly of the recess to engage the rear face of the case 62.

- A slide 87 having parallel sides 88 and a ramp 106 at one end locates within the longitudinal slot 101 in the auxiliary bolt 82 and is urged rearwardly of the slot 101 by a small spring (not shown) that lies within the slot 101. To illustrate the operation of the bolt assembly reference is made to Figures 7 to 11 that illustrate the bolt in various positions. In Figure 11 the bolt 60 is shown fully retracted against the main spring 73, the auxiliary bolt 82 is also drawn back by the engagement of the shoulders 108 against the abutments 84 on- the main bolt. In this position the ramp 106 on the plate slide 87 has pushed the ball 65 down into the recess against the spring 64. As the handle is released the main spring 73 urges the bolt 60 outwardly driving the bolt and the auxiliary bolt 82 to the position shown in Figure 10. The auxiliary bolt 82 engages the wall of the aperture in the front of the case 62 and is prevented from further outward movement. At this stage the auxiliary bolt 82 is clear of the slide 87 which allows the spring 64 to urge the ball.65 upwards to engage the transverse slot 110 in the underside of the auxiliary bolt 82. With the ball 65 nestling between the main and auxiliary bolt 60 & 82 the main bolt 60 is held by the auxiliary bolt in the latch at position shown in Figure 10. As the door is closed the inclined face 81 on the tongue of the bolt 60 rides up the strike plate (not shown) forcing the main bolt 60 and auxiliary bolt 82 back into the case 62 resulting in the ramp 106 on the slide 87 forcing the ball 65 back into the recess against the spring 6 . Once the door has closed and thus moved clear of the strike plate, the auxiliary bolt 82 is held inside the case 62 by the door jamb but the main bolt 60 is free to be urged out by the main spring 73 to the deadlocked position shown in Figures 7 to 9. Thus the lock as the advantageous feature that the bolt is automatically thrown out for about 1 inch every time the door is closed regardless of whether a key is used on either handle. The main bolt 60 thus assumes the deadlocked position every time the door is closed. However, it is understood that a suitable latch may be provided to hold the main bolt in the latched position on closure of the door and this latch (not shown) may be released by a key or a press button on either handle to thereby effect the deadlocking feature. The handle assemblies 5 & 7 are illustrated with particular reference to Figures 14 to 23 which illustrate a handle assembly which may be an exterior or interior assembly but for descriptive purposes an exterior assembly is described. As shown with particular reference to Figure 15 the assembly comprises a circular rose 30 into which the boss 201 of a cylindrical body 5 is located to be rotatable thereto by a circlip 202. The cylindrical boss 201 forms part of a handle assembly that includes, as shown in Figure 1, a lever 6. The body 5 of the handle assembly is provided with a centrally positioned internal bore 21 which is generally of circular cross-section but sometimes is of a figure eight cross-section. The bore 21 houses a removable core that,^' in the case of the exterior handle^' 5, is a key operated cylinder or in the case of the interior handle 7, may be a keyed cylinder, or turn screw. In either case the core has a tail 205 that extends into the central area of the handle assembly. The tail 205 is located within a coaxially mounted tail extension 230 to which it imparts rotational motion. The tail extension 230 is rotationally coupled coaxially to one end of a connecting spindle member 207 to impart drive at certain relative angular orientations. As shown with particular reference to Figure 14 the tail extension 230 is provided with a arcuate segment 206 on one side that engages a projection formed on the adjacent side of the connecting spindle member 207 so that a certain amount of rotation of the tail extension 230 allows free movement or, float between the two members, but once the projection and segment 206 engage rotational movement is transmitted. The number and position of the projections may vary so that the degree of free movement of float can vary depending on the type of lock that is required. The spindle connecting member 207 has a cylindrical end 208 with a bore 214 of rectangular cross-section which is arranged to mate with and impart rotation movement to a similarly cross-sectioned spindle 40 which interconnects and imparts drive between the cylindrical ends 208 of the spindle connecting members 207 in both handle assemblies 5 and 7. The handle assembly also includes a clutch mechanism that includes a splined main drive shaft 24 comprising a hollow cylindrical spigot 209 through which the cylindrical end 208 of the spindle connecting member 207 is arranged to extend for free rotation. The splined exterior of the free end of the drive shaft 24 is connected as described earlier to impart drive to the hub assembly 3 (Figure 3). The tail extension 230 and the spindle connecting member 207 are also located within a cylindrical clutch cage 216 that is positioned within the interior of the cylindrical boss 201. The interior of the clutch cage 216 is provided adjacent one end with a land or arcuate projection that is arranged to engage the external periphery of the tail extension 230 so that rotation of the tail extension 230 can, on certain relative orientations, impart rotation to the clutch cage. In a manner similar to the manner in which rotation is imparted between the tail extension and the connecting spindle member, a capacity for free movement or float is provided between the spindle tail extension 230 and the cage 216. In the latter case of free movement between the cage 216 and the tail extension 230 the free movement takes the form of a spring overload where only under abnormal or infrequent circumstances does relative motion take place against a spring bias (not shown) . As shown with particular reference to Figure 14 the periphery of the cage 216 is provided with a pair of substantially triangular cut-outs 250 on each side. Each triangular cut-out 250 embraces two mutually perpendicular side portions 251 and 252 joined by an inclined portion 253 via small steps 254. A cross-member 219, again shown in detail in Figure 14, comprises an annular washer with an internally splined aperture 223 and a pair of diametrically extending projections 229. The diametrically extending projections 229 are arranged to extend through the triangular cut-outs 250 in the side wall of the cage 216. The washer of the cross-member 219 is located within the central aperture of the cage against a spring 260 which rests on an internal angular ledge 261 shown in Figure 15. In this manner rotation of the cage 216 causes the cross-member 219 to move along the inclined wall 253 longitudinally of the cage from two positions; one adjacent one leg 251 of the triangular cut-out and another adjacent the other leg 252.^' The cylindrical boss 201 of the handle is provided with a pair of diametrically opposed longitudinal slots 222, through which the projections 229 of the cross-member extend. .When the cross-member 219 is in the full line position shown in Figure 15 the. cross-member 219 and the projections 229 locate within recesses 221 within the wall of the rose thereby locking the boss and handle against the rose. -' At the same time the internally splined aperture 323 of the cross-member is clear of the end of splines on the drive shaft 24 so that the shaft is disconnected from the clutch assembly and handle. If the handle is forced, the projections distort but drive to the shaft to release the bolt is not effected. Rotation of the cage 216 by rotation of the tail 205 or spindle 40 has the effect of causing longitudinal displacement of the cross-member 219 from the full line position to the dotted configuration shown below the full line configuration. As can be seen in Figure 18 which is a cross-section taken through the dotted configuration, in this situation the projections 229 of the cross-member locate within an annular recess 261 in the rose thereby allowing relative rotation of the handle to the rose and imparting rotational drive through the splined location of the cross-member on the end of the drive shaft. In the dotted profile the internally splined aperture on the cross-member is in positive engagement with the splines on the drive shaft. Although not shown in detail in Figure 15 a spring 270 is positioned between the inner end of the rose 30 and the handle boss 201 to cause the handle to return to the neutral (horizontal) position after rotation in either direction.

Outwardly of the tail extension is a flat washer 231 with a central hole which permits the passage of the tail but for some functions it will not allow the tail to locate in the slot in the tail extension until the tail has been axially rotated and for these functions the core is spring biassed outwardly and after rotation the core and tail are pushed inwardly to engage the extension.

Different functions employ a selection of the following variations relating to the cores and tail types.

In Figure 19 the most commonly used type 1 tail 330 is shown with legs 331 and a rectangular blade 332. In Figure 20 a type 2 tail with side slots 334 and ears 337 is shown said tail is used in conjunction with a. type 2 washer 230 where the washer hole takes the form of circular hole 335 with slots 336 and the diameter is sufficient to allow rotation of the tail once the ears 337 on the tail have passed through the slots that is the distance a is less than diameter b.

Figure 22 shows tail slot type 1 in tail extension which is a slot parallel to the unrotated tail in which the tail under spring bias is held with negligible free movement between the two parts.

Figure 23 shows tail slot type 2 in tail extension which is a slot orthogonal to the unrotated tail. After rotation of the tail extension by 90° by turning the inside core 90° and locking the exterior operating handle simultaneously rotates this type of extension so that the tail can then be moved into engagement for the purpose of temporarily unlocking the exterior handle. Key removal relocks the handle. For the hotel function a spindle with integral ratchet spring biassed inwardly is provided whereby when the flap is rotated the ratchet disengages the spindle which translates inwardly thereby allowing the tail under other spring bias to move into re-engagement with the tail extension so allowing the tail and associate core to actuate the adjacent clutch. Cores are provided as a means of driving rotationally the adjacent clutch or as a means of driving the spindle so as to drive the clutch in the opposite operating assembly. Cores in some case may be immoveable. The rotation links 206 and 207 accommodate lever rotation and rotation of the core locking device while ensuring that this rotation does not crosslink with lever rotation.

On an interior or passageway handle or lever where the lever must always drive the bolt and the clutch is never disengaged, this feature can be achieved by not employing a cross-member 219 and employing feet 227 or by uncoupling the spindle 40 from the cage 216 and placing the cross-member 219 into the engaged position. As shown with particular reference to Figures 8 and 9, a flap 400 is mounted on the spindle 40 adjacent the crank 93. The crank includes an abutment 401 that has the effect of imparting motion of the bolt 60 to the spindle 40 by the abutment moving the flap 400 from the position shown in Figure 8 to the position shown in - Figure 9. This movement causes the spindle 40 to drive the clutch in the exterior handle from the disengaged position to the engaged position. Furthermore the flap 400 can also be used to ensure that the crank 93 is fully rotated to a position corresponding to a fully locked position since if the arm is restricted from full rotation the spindle drive flap 400 will exert a force on the crank 93 as it moves the clutch to the locked position. The flap 400 may be utilized in functions having thumbturns or keyed cores but a direct implication being that each time the latch is retracted the clutch is simultaneously positioned in the drive position. The lock described above is capable of fulfilling many varying functions which generally conform to the U.S. standard relating to knob assembly locks. Operation of various components of the lock vary depending on the use of the lock but one consistent feature is that the lock bolt always deadlocks on full extension which occurs when the auxiliary bolt is held depressed.

A brief summary of the various functions of the lock now follows with reference to Figures 24 to 39 which are schematic illustrations of the lock components with reference numerals used in Figure 24 according to the references used earlier in the specification. Unless specified the tail 205, tail extension 20 and washer 231 are type 1 illustrated in Figures 19 and 22.

(a) Privacy Lock - Figure 24

Lever unlocking from both sides. Thumbturn locking of external lever from internal lever. Flap 400 unlocks external lever when bolt retracted. Emergency unlocking from exterior by one of coin slot to turn coin operated core. Interior lever always unlocked and free to retract bolt.

(b) Corridor Lock - Figure 25

Lever on one side of a door can be locked by a keyed core on other side after door has been closed. Bolt withdrawal unlocks clutch in key cored lever. Other lever always unlocked and free to retract bolt.

(c) Exit Lock - Figure 26

Lever on exterior can be locked by thumbturn on interior lever. Once locked must be unlocked by thumbturn. Internal lever always unlocked and free to retract bolt.

(d) Exit Latch - Figure 27

Outside lever fixed. Internal lever always unlocked and free to retract bolt. (e) Passage Lock - Figure 28

Both levers always free to retract bolt.

(f) Classroom Lock - Figure 29

Internal lever always unlocked and free to retract bolt. External lever has locking core which can be unlocked and left unlocked.

(g) Store Room Lock - Figure 30

Same as (f) but there is no float so that on key removal locking of exterior lever occurs.

(h) Entrance Lock - Figure 31

Internal lever always free to withdraw bolt. Thumbturn in internal lever can lock clutch in exterior lever. Once locked the recess in the tail extension is parallel and adjacent the tail so tail can be pushed against spring bias into the recess and once rotation occurs the wings of the tail in conjunction with the washer recess hold the tail in the recess even if the core is not maintained fully inwardly. Tail is moved inwardly by core movement against 'spring bias. Retraction of key relocks clutch in exterior lever.

Mechanism allows clutch to be unlocked while key is in exterior lever.

(i) Apartment - Figure 32 As for (h) but locking of external lever is effected by locking core in internal lever.

(j ) Asylum - Figure 33

Each lever can be unlocked but relocks on key removal. When unlocked, unlocked lever can withdraw bolt. (k) Communicating door - Figure 34

As for (j) but float allows lever to remain unlocked on key removal.

(1) Store Door Lock - Figure 35 Levers simultaneously locked and unlocked by key from either side. Levers can remain unlocked on key removal.

(m) Communicating Door Lock - Figure 36

As for (1) but no locking or unlocking facility on one side. Keyed core one side only.

Note: For apartment lock (i), the stone door (1) and the communicating door (m) , the direction of rotation of the clutch or clutches during locking must be in the same direction as its lever when turned downwardly for bolt withdrawal.

(n) Patio Lock - Figure 37

Exterior uncored lever can be locked by thumbturn on internal lever. Bolt withdrawal unlocks clutch in exterior lever. Internal lever always free to retract bolt.

(o) Hotel Lock - Figure 38

External lever is always locked unless its clutch is rotated by keyed core in external lever. Key removal relocks clutch. Push button 503 in internal lever drives spindle 40 longitudinally to displace the driving part of the tail from the recess 509 in the tail extension 530. Depressed spindle is held depressed by a ratchet type device 500 comprising a slide 505 spring biased 501 orthogonally to the spindle and which lodges in a recess on the spindle once it is depressed.

Rotation of internal lever causes bolt withdrawal which rotates flap 400 which rotates spindle to disengage ratchet slide 500 thereby allowing spring bias 504 to drive spindle away from tail extension 530 in exterior lever. When displaced the tail cannot drive clutch.

(p) Alternative Hotel Lock - Figure 39

As for Figure 338, but bolt is driven directly by tail in external lever. Spindle depression drives . tail from its recess in shaft end.

It is understood that the expression "core" as used herein embraces removable and non-removable keyed cylinders, thumbturns and coin turns and any other locking actuating means.

Claims (26)

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A door lock comprising a locking bolt assembly coupled to a handle assembly positioned on one side of the door; the handle assembly including a rotatable handle, a drive shaft and a clutch to selectively engage or disengage drive from the handle to the drive shaft; actuating means positioned on the other side of the door operable to actuate the clutch by a spindle connected therebetween; and a drive mechanism driven by said handle assembly to cause a..locking bolt of the locking bolt assembly to move between a partially extended latching position, an extended deadlocked position and a retracted position, the drive mechanism including a crank pivotally secured to a connecting arm to impart linear movement to the bolt.

2. A door lock according to Claim 1, wherein the drive mechanism includes means to rotate the crank.

3. A door lock according to Claim 2, wherein a cam driven by the drive shaft imparts linear motion to a slide and the slide imparts rotary motion to the crank.

4. A door lock according to Claim 3, wherein the crank is driven by a rack which is, in turn, driven by the slide.

5. A door lock according to any one of the preceding claims, wherein said actuating means comprises a rotatable handle driving a drive shaft.

6. A door lock according to Claim 5, wherein each handle is coupled to a separate slide that independently drives the crank.

7. A door lock according to any one of the preceding claims wherein a locking actuating means is provided in the handle assembly, said means being coupled to the clutch and the spindle.

8. A door lock according to any one of the preceding claims, wherein the locking bolt is .driven to the deadlocked position by the crank, said crank assuming an over-centre position when the bolt is in the extended position.

9. A door lock according to Claim 8, wherein a biasing means is provided to urge the crank into the over-centre position.

10. A door lock according to any one of the preceding claims, wherein the drive mechanism allows the locking bolt to assume the extended deadlocked position whenever the door is closed.

11. A door lock according to Claim 10, wherein the locking bolt assembly comprises a detent that when the door is open, holds the bolt in the latching position against biasing means, closure of the door against a strike plate causing displacement of the detent to allow the biasing means to urge the bolt to the extended deadlocked position.

12. A door lock according to any one of Claims 1 to - 9, wherein a catch is provided to cause the locking bolt to move to the latching position when the door is closed, the operation of the catch being controlled by the actuating means.

13. A door lock according to any one of the preceding claims, wherein the drive shaft of the handle assembly has splined engagement with the drive mechanism to accommodate for doors of varying thicknesses.

14. A door lock according to any one of the preceding claims, wherein each handle assembly includes a locking actuating means in the form of keyed cylinder or turn screw that causes rotation of the spindle that extends across the lock, the spindle being coupled to the keyed cylinder or turn screw in the opposite handle assembly.

15. A door lock according to any one of the preceding claims, wherein at least one handle assembly incorporates a clutch actuated by either a lock actuating means in said assembly or by rotation of the spindle to cause drive from the handle incorporating the clutch to the drive mechanism to be disconnected.

16. A door lock according to Claim 15, wherein the clutch comprises a clutch cage and a cross-member, the cross-member being displaceable axially of the cage as the clutch cage is rotated relative to the handle assembly from one position in which rotation of the handle causes rotation of the drive shaft and a second position in which the drive is disconnected.

17. A door lock according to either Claim 15 or 16, wherein when the drive has been disconnected the handle is locked against rotation.

18. A door lock according to any one of Claims 1 to 14, wherein an exterior handle assembly has a clutch according to either Claim 15 or 16, the interior handle being coupled to the drive mechanism to ensure that the lock can always be unlocked by turning the interior handle.

19. A door lock according to Claim 14, wherein the lock actuating means includes a tail that drives the spindle which, in turn, drives the clutch cage whereby there is selected lost motion between the drive between the tail and the spindle and the spindle and the clutch cage.

20. A door lock according to any one of the preceding claims, wherein the spindle and crank are interconnected so that in certain circumstances movement of the locking bolt actuates the mean to engage drive from the handle to the drive shaft.

21. A door lock according to Claim 20, wherein the interconnection between the spindle and the crank is in the form of a flap connected to the spindle, the flap being driven by movement of the crank against the flap to thus cause the spindle to turn.

22. A door lock according to Claim 21, whereby rotation of the locking actuating means causes the rotation of the spindle which drives the flap to assist rotation of the crank to cause the bolt to assume the extended deadlock position.

23. The door lock according to any one of the preceding claims, wherein the spindle is longitudinally displaceable by actuation of a button on the interior handle assembly to cause the lock actuating means in the exterior handle assembly to be disconnected from the clutch in that assembly-.

24. A door lock comprising a pair of handle assemblies arranged to be positioned coaxially one on each side of a door, a locking bolt assembly located within the door, a drive mechanism interconnected to the handle assemblies, whereby each handle assembly provides independent drive to the drive mechanism, the drive mechanism being operable to cause a locking bolt of the locking bolt assembly to move between a partially extended latching position, an extended deadlocked position and a retracted position, each handle assembly including a locking actuating means coupled to a clutch; a spindle interconnecting the locking actuating means of both handle assemblies, whereby actuation of the clutch causes disconnection of the drive from either handle to the drive mechanism^", the drive mechanism including a crank that allows the locking bolt to assume a deadlocked position with the crank over-centre when in the extended position.

25. A door lock according to Claim 8, wherein the connecting arm has an abutment that engages the body of the bolt assembly when deadlocked to prevent inward forced movement of the bolt.

26. A door lock substantially as described herein with reference to and as illustrated in the accompanying drawings.