AU2002300101B2 - A Lock - Google Patents

Description

Title A Lock (div of 59403/00).

A Lock Field of the Invention This invention relates to door locks and in particular relates to locks for security doors.

Summary of the Invention According to the invention there is a lock for a door or the like, including a strike plate, a casing, a locking means including a key operable cylinder, a latching means including a latch bolt displaceable against resilient biassing means between an engagable extended configuration and an intermediate partly extended configuration in which the latch bolt is restrainable to enable latching and a disengaged retracted configuration where the latch bolt is substantially within the casing, an operating means by which to operate the latch bolt including at least one hand operable member in an external assembly, said hand operable member being operable to retract the latch bolt, said lock being lockable by the locking means whereby to render the hand operable member unable to cause retraction of the latch bolt, said lock being characterized by a latch bolt leading portion which is similarly curved or bevelled on both sides to facilitate inward displacement by the strike plate when being engaged by the strike plate from either side.

Preferably, the hand operable member comprises a lever comprising part of an exterior handle assembly Preferably, locking of the lock is characterized by the lever being restrained against displacement.

Preferably, the lever is removal by rotation beyond the operating limits.

Preferably, the operating means includes and operating arm that operably interconnects the latch bolt and lever, said operating arm retains the latch bolt partly extended to enable latching.

Preferably, the lock includes an outwardly biassed auxiliary bolt operably engagable with the operating arm to retain the operating arm to retain the latch bolt partly extended against biassing means.

Preferably, the auxiliary bolt has a leading portion which is similarly curved or bevelled on both sides to facilitate inward displacement by the strike plate when being engaged by the strike plate from either side.

Preferably, the locking means includes an interior hand operable locking lever io that is actuateable to lock the lock Preferably, the locking lever supported in a recess.

Preferably, the locking means includes an angularly cam operably connected to the cylinder and a deadlocking member operably coupled to a locking lever and coupled within a first range of displacement to the cam whereby the deadlocking member can be displaced to and from the locking configuration by the cylinder and locking lever and the cam can be rotationally displaced by deadlocking member displacement, said first range corresponding to the lock being lockable and unlockable by both the locking lever and cylinder, and when the deadlocking member is in a position corresponding to a locked lock the cam can be further rotated by the cylinder to prevent the deadlocking member from being displaceable by the locking lever.

Preferably, the lock includes an auxiliary bolt supported by the casing and having a leading portion displaceable from an extended position where it protrudes from the casing, an outwardly biassed displaceable latch bolt supported by the casing and having a leading portion displaceable between a fully extended position where it protrudes from the casing and a retracted position where it is substantially within the casing, the lock having a pre-latching configuration in which the auxiliary bolt is in the extended position and the latch bolt is restrained from displacing to the fully extended position by a first moveable member itself restrained in relation to the casing by means including the auxiliary bolt said means including the auxiliary bolt being rendered inoperative by displacement of the auxiliary bolt from the extended position, operating means by which !1.

3 to retract the latch bolt including the first moveable member and a hand operable member urged by slide means towards an undisplaced position and operable to cause the first moveable member to displace to cause the latch bolt to displace towards the retracted position, locking means to restrict the bolt from displacing to the retracted position including a key operable barrel and a hand operable locking lever.

Preferably, the latch bolt is supported within the casing for rectilinear sliding movement.

Description of the Drawings Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is an isometric view of a lock in a door with a fully extended latch bolt, where the front edge of the lock body and the interior lever assembly is shown with the "snib" locking lever Figure 2 is schematic side view of a deadlocked lock body showing the latch bolt supported between casing ribs extending from the front edge of the casing, Figure 3 is a schematic side view of the lock body with the latch bolt held partly retracted, Figure 4 is a schematic plan view of the lock body, Figure 5 is a partial front edge view of the lock body showing the latch bolt aperture wholly within a single casting and having radiussed comers; this single casting including the front edge of the casing, Figure 6 is a side edge schematic view of a lever assembly having a slide, Figure 7 is a partial sectional schematic view of the lever assembly of Figure 6 from the back sectioned through the slide, Figure 8 is a partial sectional schematic view of the lever assembly of Figure 6 from the back sectioned through the driven cam, Figure 9 is a is a side edge schematic view of an interior lever assembly, 4 Figure 10 is a partial view of the back of the lever plate of Fig. 9 showing the barrel and surrounding cylinder housing, Figure 11 is the sectional view BB Figure 9, Figure 12 is the sectional view AA Fig 9, Figure 13 is a schematic plan sectional view of a lock body with a protruding bolt located within a strike plate, Figure 14 is a schematic plan sectional view of a lock body with a protruding latch bolt located within a strike plate where the bolt has been forced against the edge of the strike plate aperture and the lock has been forced away from the door 1O jamb.

Figure 15 is a partial sectional schematic side view of a lock body with a pivotally displaceable latch bolt, Fig 16, is a partial plan view of the lock of Fig Description of the Preferred Embodiments The accompanying drawings illustrate a number of embodiments of the invention which provides a number of locks and portions of locks which are applicable to other types of locks without being limited to locks for security doors. Generally, the same reference numerals are used for like components in all embodiments as shown. The positional prepositions such as rear forward used with reference to the accompanying figures and are used to assist in description of the preferred embodiments and have in general no absolute meaning One embodiment of the invention as shown in Figures 1 and 2 comprises in summary, a lock comprising a lock body assembly, a pair of handle assemblies and a strike plate. The lock body includes a casing 10 supporting other component parts, including a latch bolt 20 supported within the casing and displaceable under biasing of spring 30 to extend from the casing where it can engage in a recess 2 within the strike plate 1, as shown in Figure 13, which has a fin 1A engageable by the latch bolt to facilitate latching during which process the latch bolt is driven inwardly as the leading portion slides up the ramped portion of the fin. The latch bolt is retractable by operation of a lever 61 in a lever assembly 60 connected to the lock body by a shaft 55 as shown in Figure 9. In a preferred embodiment there is within the casing a deadlocking slide Figure 2, which can be moved into engagement with a shoulder on the latch bolt to restrict inward displacement of the latch bolt. This is caused by actuation of a key operable barrel 112, Figure 1, or actuation of other actuating means.

In preferred embodiments the lock has a pre-latching configuration to enable latching with the strike plate. In this pre-latching configuration the latch bolt is retained in a partly extended position, outwardly biased but restrained from outwardly displacing by means including the auxiliary bolt 70; in normal operation inward displacement of the auxiliary bolt and latch bolt during latching causes the auxiliary bolt to displace to a configuration where it cannot act to cause restraint of the latch bolt thereby enabling the io latch bolt to displace to the fully extended position when it becomes aligned with an aperture in the strike plate.

The locks provided by the invention are different from those described in the prior art both in construction and in function. The invention provides locks which include some or all of the following features: unlatching when inverted by having levers that function in either angular direction, reduced manufacturing cost by combining the cylinder with the lever assembly, levers that can be quickly dismantled for packaging reasons, a casing of increased strength, resistance to forced entry, improved means of restraining the latch bolt partly retracted to facilitate latching.

In an embodiment and as shown in Figures 2 and 5, the lock casing 10 is box like having a front wall 16, a rear wall 19 and upper and lower walls 18 and an upper tab and a lower tab by which the casing is attachable to a door. Within the front wall 16 there is an aperture 11 through which a latch bolt 20 has passage to be displaceable to an extended position where it protrudes from the casing.

In a preferred embodiment there is also an aperture 14 through which the auxiliary bolt 70 has passage to be displaceable to an extended position where it protrudes from the casing.

Within the side walls of the casing there are apertures which support lock body internal component parts. The casing comprises a front portion and a rear portion abutting at a plane orthogonal to the direction of displacement of the latch bolt and intersecting the casing; the front portion comprising the front wall 16 with the aperture 11, the fixing tabs, side wall portions on each side and upper and lower end wall portions which together comprise a single casting to provide greater strength.

The front portion preferably has blades 13 extending rearwardly which pass through mating apertures in the rear casing portion and which are preferably peened over to secure the two portions together as shown in Figure 2. Within the front portion there are preferably internal webs 12 joining the front wall 16 to a side wall to strengthen the casing adjacent the aperture 11 while the aperture 11 has radiussed comers, Figure to resist cracking the additional casing strength providing greater support for the bolt so io that the extended bolt and casing are better able to resist the side loadings that occur during attempted forced entry.

In preferred embodiments the latch bolt 20 is of a solid box like construction with radiussed top and bottom edges to mate with the radii in aperture 11 and it is supported between the webs 12 which are elongated rearwardly to provide therebetween a substantially parallel walled recess in which to support the latch bolt while enabling it to be freely, substantially rectilinearly, slideable. This latch bolt has a leading portion 22 which is displaceable between a retracted position where it is within the casing and a fully extended position where it protrudes from the casing. The latch bolt is outwardly biassed and moveable by spring 30 and inwardly moveable by a first moveable member said first moveable member including an operating arm 40, which is operably connected to the lever 61. The latch bolt rearwardly has a recessed portion 24 within which the operating arm 40 locates in front of a protruding drive shoulder 23 of the latch bolt.

Rearward movement of the operating arm 40 causes the arm to engage the drive shoulder 23 and move it rearwardly to retract the latch bolt.

In preferred embodiments, Figures 3 and 4, where the lock has a "pre-latching" configuration in which the latch bolt is retained partly extended prior to latching, the latch bolt leading portion has both sides similarly curved as shown in Figure 4, progressively reducing in width by being curved, radiussed and/or bevelled on the sides), to facilitate inward displacement by the strike plate when engaging the leading portion on either side. This is to accommodate both left and right hand opening doors. In this embodiment, the operating arm 40 passes across the latch bolt so that a shoulder 7 41 on its free end is engageable by a shoulder 71 of the auxiliary bolt 70 to restrain the portion of the operating arm 40 which engages shoulder 23 from displacing in a forward direction Depression of the auxiliary bolt causes the shoulder 71 to move out of the path of movement of shoulder 41 to preclude engagement between the said shoulders and so enable the latch bolt to displace, under the action of spring bias, to the fully extended position.

In another preferred embodiment, Figure 15, the latch bolt comprises a pivotal bolt 29 angularly displaceable and supported on a pin 29A within the casing which 1O passes from one side to the other to be supported in both sides of the casing. It is similarly spring biased to displace towards an engageable position and moveable away from this position by the operating arm acting similarly as described above.

In an embodiment configured for sliding doors, the pivotal latch bolt operates entirely or substantially within the confines of the casing and the strike plate comprises a catch plate with a protruding portion with an engageable recess which has passage through the aperture 11 to be engaged by the latch bolt.

In an embodiment configured for a hinged door the pivotal latch bolt has a leading portion 22 which is displaceable between a retracted position where it is within the casing and a fully extended position where it protrudes from the casing; the leading portion preferably having a hooked end which engages in and behind the strike plate aperture. This latch bolt leading portion preferably has both sides similarly contoured as shown in Figure 16, and as described above in relation to the rectilinearly displaceable latch bolt, to facilitate inward displacement by the strike plate when engaging the leading portion on either side. This is to accommodate both left and right hand opening doors.

In preferred embodiments where the lock has a "pre-latching" configuration in which the pivotal latch bolt is retained partly extended prior to latching to facilitate latching, the operating arm 40 passes across the latch bolt so that a shoulder 41 on its free end is engageable by shoulder 71 of the auxiliary bolt 70 as described above in relation to the rectilinearly moveable latch bolt. Depression of the auxiliary bolt causes the shoulder 71 to move out of the path of movement of shoulder 41 to preclude engagement between the said shoulders The auxiliary bolt, Figure 3, preferably comprises a leading portion 75 which is displaceable to extend from the casing under the action of biasing spring 73 and a rear portion comprising an angled face 72 adjacent the shoulder 71 extending towards the latch bolt. The casing has a ramped rib portion 17 which when the auxiliary bolt is fully extended is adjacent the angled face 72 whereby inward displacement of the auxiliary bolt by strike plate fin engagement during latching causes face 72 to slide up the ramp 17 to displace the shoulder 71 away from the latch bolt operating arm shoulder 41 and out of the path of movement of the shoulder. The rear portion of the auxiliary bolt is free to move vertically to a limited extent against biasing means derived from the biassing spring 73. The auxiliary bolt leading portion preferably has both sides similarly contoured as shown in Figure 4, progressively reducing in width by being curved, radiussed and/or bevelled on the sides), to facilitate inward displacement by the strike plate when engaging the leading portion on either side.

In an embodiment, the latch bolt, Figure 3, is driven inwards against biasing by spring 30 by the operating arm 40 which is supported on a cylindrical portion of operating cam 50 which is supported in circular apertures in the side walls of the casing. The operating arm has an engageable, preferably substantially opposite, shoulder 42 radially displaced from, and preferably on the opposte side of its axis of rotation, whereby forward displacement of the shoulder 42 causes the operating arm to rotate to engage the drive shoulder 23 of the latch bolt to drive the latch bolt rearwardly and inwardly. The operating cam 50 being coupled to the lever 61 in the external lever assembly 60 by the substantially rectangular shaft 55, is caused to rotate when the lever is rotated by lever operation. The shaft 55 engages in a mating coaxial recess in the operating cam.

In an embodiment, there is an operating slide 90 operably interspaced between the lever 61 and operating arm 40 to enable the latch bolt to be displaced rearwardly by lever rotation in either direction. The operating slide 90 may be within the lever assembly, Figures 6 to 8, but it is preferably within the casing 10, Figures 3. In the latter case, the operating cam 50 has two, (preferably substantially opposite) shoulders 53 one on each side of its axis of rotation and the operating slide has a corresponding shoulder 91 one on each side of the axis of rotation of the operating cam adjacent the said operating cam shoulders 53 and engageable by the corresponding shoulder.

The operating slide is supported between webs 12 and web 13 in the casing and is free to slide. It is biassed by springs 92 which locate within elongated recesses within the operating slide, towards the operating cam. In the undisplaced position the shoulders 91 are held pressed against the shoulders 53 to cause the operating cam to adopt an undisplaced position. Preferably the shoulders 53 are winged extensions of the io operating cam and the shoulders 91 mate with shoulders 53 in the undisplaced positions of the operating cam and operating slide. On the operating slide is a pinned protrusion 93, preferably being an extension to the lower shoulder 91, which is engageable with the operating arm shoulder 42. Rotation of the lever 61 in either direction causes one of the shoulders 53 to displace the operating slide away from the cam 50 to cause the portion of the operating arm which engages the drive shoulder 23 to displace rearwardly.

Although shown sliding in a direction parallel to the direction of latch bolt displacement, and this is the preferred direction of movement), the operating slide can move in any direction within the plane of the latch bolt; provided the pinned protrusion 93 and shoulder 42 are radially displaced from the axis of rotation of the operating arm and provided the pinned protrusion 93 displaces in a direction having a component tangential to the axis of rotation of the operating arm.

In another embodiment Figures 6, 7, 8, operating slide 90 is within the lever assembly 60 and the operating cam 50 is coupled directly to the lever 61 by splined engagement as shown in Figure 7. In this embodiment the operating arm 40 is attached directly to a cylindrical boss which has a recess to receive to operably couple to the shaft said boss being supported within apertures in the side walls of the lock body casing.

In this embodiment the operating arm is caused to angularly displace by boss angular displacement itself angularly displaced by angular displacement of the drive shaft.

The operating slide 90 on one layer, Figure 7, has the shoulders 91 and the cam has wings 53 on the same vertical layer, so rotation of the lever and cam in either direction causes one of the wings 53 to drive the operating slide away from the axis of r rotation of the cam 50 against urging by the biassing means comprising spring 92A. (A layer being a vertical plane parallel with a side of the casing). On another layer, Figure 8, the slide has has a protrusion 93 which locates in a recess 56 in a disc-like cam 100 member. This cam 100 has an integrally attached shaft portion 55, which in useage connects to the boss connected to the operating arm within the lock body. The disc-like cam 100 peripheral recess 56 has clearance below the protrusion 93 and a radial shoulder 101 adjacent the top of the protrusion 93 so that operating slide movement in response to lever rotation in either direction causes the operating slide to displace away from the axis of rotation of the cam 50 against urging by the spring 92A to rotate the cam 100 in the same direction, a direction corresponding with actuation of the operating arm to retract the latch bolt. As described above in relation to a previously described embodiment, in the undisplaced positions of the operating slide and operating cam, the shoulders 91 are held pressed against the shoulders 53.

In an embodiment, the latch bolt is securable in the fully extended position by a deadlocking slide supported adjacent the latch bolt within the casing and having a leading portion 81 which can be actuated by one or other actuating means to displace towards the latch bolt to engage it wherein the leading portion 81 engages behind the shoulder 28 of the latch bolt, Figure 2, to restrain the latch bolt from being moved inwardly. It can be seen from Figs 2, 3 and 15 that the deadlocking slide also has a sideways protruding pin 80A that locates in front of a stopping shoulder 90A of the actuating slide to restrain the actuating slide against displacement in a forward dircetion whereby causing the exterior lever to be unable to be rotated to cause the latch bolt to retract.

The actuating means includes a key operable barrel 112, Figure 1 and Figure 9, comprising a portion of a locking cylinder operably coupled to an angularly displaceable cam 110, Figure 3. This cam has an armed extension 111 which locates within a concave recess 82 in the deadlocking slide which is bounded by a lower shoulder 83 and an upper shoulder 84. The deadlocking slide can be moved towards and away from the latch bolt by cam rotation by the armed extension 111 engaging one of the shoulders 84 or 83 respectively and the cam can be rotationally displaced, within limits, by deadlocking slide movement. While the armed extension remains within the bounds of 11 the shoulders 84 and 83 it remains operably coupled to the deadlocking slide, for convenience called a first range of coupled movement but when the deadlocking slide is substantially fully travelled towards the latch bolt and is in the deadlocking position, for convenience called a second locking configuration, the cam can be partially further rotated to effect a surface of contact between the extension 111 and an angled shoulder 84A of the deadlocking slide extending from shoulder 84 which is substantially orthogonal to the cam centre of rotation thereby preventing the deadlocking slide from driving the cam, for convenience called a first locking configuration, at which position the the deadlocking slide cannot be actuated by the other actuating means and the lock can only be released from this configuration by cam rotation. In a preferred embodiment, the cylinder comprises a double cylinder having two barrels, one on each side of the cam, and connected to the cam, said cam being operable by either barrel.

In a preferred embodiment the key operable cylinder comprises the angularly displaceable cam 110 supported in apertures within the side walls of the casing and a key operable angularly displaceable barrel 112 supported in a cylinder housing 152 comprising a portion of the lever assembly 60, Figure 9. The barrel preferably has a peripheral end side protrusion 151 in line with the wafers 153 and similar in form to an extended wafer. The housing has the normal longitudinal elongated slotted 155 recesses to facilitate wafer movement as is well known; however in this case one recess has an end wall 156 while the other has an aperture 157 to permit passage of the end side protrusion so that when the barrel is inserted through the aperture and rotated it cannot be removed. Preferably the barrels and cam are coaxially supported and the barrel extension engages in a recess 158 in the cam, Figure 3, to operate the cam.

Once assembled the barrel movement is restricted by its engagement with the cam to positions where the protrusion 151 does not become aligned with the aperture 157 thereby ensuring the barrel cannot be removed in normal usage. In some embodiments the lock body is mounted within a frame having thin walls and the lever assemblies are mounted on the external surface of the frame and the barrels extends through the frame to communicate with the lock body. To accommodate variation in the distance between the lever assemblies and the lock body the engagement between the barrels and cam recess is splined in form.

The "snib" actuating means, comprises a cylindrical cam 121, Figure. 3, having a coaxial recess engageable by the shaft 163 of a snib lever 164, Figure 1,9 in the interior lever assembly. The cam 121 has an armed extenstion 122 with a protruding pin which protrudes sideways to locate within a substantially horizontal recess 85 in the deadlocking slide so that the slide is moveable between extreme positions by snib lever rotation subject to the deadlocking slide not being restrained in the first locked configuration.

The lever 61, Figure 9, is removeably retained within the lever assembly 60. It comprises a hand operable ball or lever 62 integrally connected to a cylindrical shaft 63 which is retained free to rotate within a substantially cylindrical aperture 64 in a boss of the lever assembly backplate 66. The shaft has peripheral end protrusions 67 and the boss has elongated slotted apertures 68 to permit pasage of the protrusions 67. When the lever is assembled onto the back plate and is rotated the lever is retained by the protrusions. Preferably there are two opposite protrusion and the coupled operating cam requires less than 90 degree movement so that once the lever is connected by the shaft to the operating cam its movement is restricted so that the apertures 68 and protrusions 67 do not align in normal usage. It will be appreciated that prior to assembly of the lever assembly to the casing both barrels and levers can be inserted and/or changed as is required.

In a preferred embodiment a snib locking lever, Figure 1, 9 comprises a cylindrical boss portion 161 integrally connected to its associated shaft 163 which extends from the underside of the back plate and has a hand operable portion 164 within a concave recess 165 in an end of the back plate as distinct from "snib" levers in common use which sit on the face of the back plate and protrude from the form of the back plate the recess providing protection from exterior operation of the member.

Preferably the hand operable member 164 comprises two arms which are angularly displaced in relation to each other and project substantially radially from the cylindrical boss portion. They are relatively disposed at approximately the same angle as the cam 121 moves between its limits of rotation and angularly disposed so that when the deadlocking slide is in the deadlocked position a side of the operable portion 164 is adjacent a side of the recess while when the deadlocking slide is at the other extent of its 12 13 travel, the unlocked position, another side of the operable portion 164 is adjacent a side of the recess these obviously recognizable configurations providing a visual indication of the configuration of the lock; i.e. locked or unlocked This member is substantially supported by the shaft 163.

In a preferred embodiment the lock includes a latch bolt supported within a casing and having a leading portion displaceable between a retracted position and a fully extended position, the latch bolt being engageable within an aperture in the strike plate in catching engagement and also being in longitudinal engagement to restrain the latch io bolt from being longitudinally removed from the strike plate. This is achieved by having a channel 400 in the side of the latch bolt which, in relation to an extended latch bolt, comprises an exposed orthogonal elongated concave recess extending from top to bottom of the side of the latch bolt. This channel, preferably has an inclined wall 401 on the leading side of the latch bolt engageable by the edge 402 of the strike plate recess when the latch bolt is forced against the edge 402 of the recess. The inclined wall enables the latch bolt to be retracted during normal unlatching, without catching on the edge of the aperture whereas a recess having "straight" side walls may catch and impede the latch bolt from retracting. It will be appreciated that the steeper the angle the better the longitudinal engagement but the greater the risk of fouling a satisfactory trade off has been achieved with the design shown in the figures. In the case of the pivotal latch bolt 29 the hooked portion 213 engages behind the aperture in the strike plate.

In a preferred embodiment the strike plate, Figure 13 and Figure 14, comprises a fixable first portion 460 connected to a second portion 461 by a deformable interconnecting portion 462 said second portion including the engageable aperture within and behind which the latch bolt is engageable; the second portion being displaceable relative to the first portion to restrain relative displacement between the bolt and plate aperture. Such a strike plate enables the latch bolt and strike plate aperture to remain engaged while they are displaced together relative to the fixed portion attached in usage, to a doorjamb. This mutual displacement can occur during attempted forced entry when a door is subjected to side loadings.

The positional prepositions such as rear forward are used in reference to the accompanying drawings to assist in description of the preferred embodiments and have in general no absolute other significance.

Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers or steps but not the exclusion of any other integer or group of integers.