Field

[0001] The present invention relates to a privacy mode device for a lock assembly, and also to a lock assembly having such a privacy mode device for locking an external door handle against rotation.

[0002] The present invention has particular application to a lock assembly that is able to operate in different modes. In the case of the lock assembly being employed on a door, the modes of operation will typically include: (i) a latching mode or passage mode in which the turning of either the inner door handle or outer door handle can move a bolt of the lock assembly between an extended position for latching engagement in a complementary recess provided in a frame of the doorway, and a retracted position for disengagement from that recess; and (ii) a privacy mode in which retraction of the bolt by a door handle on the outer side of the door is prevented. It will be convenient to describe the invention with reference to such an embodiment, although it will be appreciated by persons skilled in the art that the invention is not limited to this particular context.

[0003] The privacy mode device of the invention can be employed in a range of different types of lock assemblies and lock arrangements and may be used in domestic as well as in commercial and/or industrial security applications.

Background

[0004] Locks that are able to function in multiple modes are known. Indeed, the present applicant already markets lock assemblies for doors that are configured to operate in any one of (i) a passage or latching mode, (ii) a privacy mode, and/or (iii) a deadlock mode. As noted above, in the passage mode, the turning of either door handle withdraws the bolt from a first extended position to a retracted position to enable the door to be opened. In the privacy mode, which may be activated by a button provided on an inner side of the door, retraction of the bolt by the door handle on the outer side of the door is prevented. Turning the inner door handle disables the privacy function, again permitting the door to be opened from the outer side. In the deadlock mode, a key may be used to lock the bolt against retraction from the latched state; e.g. by either door handle. For example, the key may throw the bolt to a further extended position to lock the door securely and make forced entry more difficult.

Summary of Invention

[0005] It is an object of the present invention to provide a lock assembly with an improved privacy mode, especially a lock assembly in which a privacy mode can be more easily and/or more reliably operated by a user.

[0006] According to one aspect, the present invention provides a privacy mode device for a lock assembly, comprising: an actuator element for manual input of an actuation force by a user for activating a privacy mode of the lock assembly, whereby the actuator element is configured for movement from a start position to an activated position; and a force transfer mechanism for transferring the actuation force from the actuator element to a snib member of the privacy mode device to move the snib member to lock an external door handle of the lock assembly against rotation in the privacy mode. The force transfer mechanism is configured to modify the force transferred to the snib member progressively as the actuator element moves from the start position to the activated position.

[0007] In this way, the force transfer mechanism of the privacy mode device can be configured to provide or impart a large initial mechanical actuation force to the snib member as the actuator element moves from the start position to the activated position. A large initial force can be required for overcoming or breaking a magnetic attraction that holds or retains the snib member in a non-activated position.

[0008] In a preferred embodiment, the force transfer mechanism comprises a lever mechanism. The force transfer mechanism preferably includes a force output member configured to pivot about an axis, the force output member extending from the pivot axis for engagement with the snib member. An area of contact between the force output member and the snib member progressively moves radially outwardly from the pivot axis as the actuator element moves from the start position to the activated position.

[0009] In a preferred embodiment, the force transfer mechanism includes a force input member configured to pivot about the pivot axis, the force input member extending from the pivot axis for engagement by the actuator element as the actuator element moves from the start position to the activated position. Preferably, the force input member is integrally or unitarily formed with the force output member for common pivoting movement about the pivot axis. Thus, the force input member and the force output member may be configured in the force transfer mechanism as a lever arrangement which operates to create or generate a mechanical advantage in imparting or transferring the actuation force from the actuator element to the snib member.

[0010] In a preferred embodiment, the snib member is configured to move essentially linearly between a retracted position in a non-activated state and an extended position when activated in the privacy mode. In this regard, the force output member engages with the snib member to move the snib member from the retracted position to the extended position as the actuator element moves to the activated position. Because the snib member may be held or retained in the retracted position by a“keep” magnet or solenoid in the non-activated state, there may be a certain threshold force required to overcome or break the magnetic attraction holding the snib member in the retracted position when the privacy mode is activated.

[0011] In a preferred embodiment, respective contact surfaces of the force output member and the snib member form camming surfaces over which the area of contact between the respective contact surfaces progressively moves radially outwardly from the pivot axis as the snib member is moved from the retracted position to the extended position. In this way, the force transferred to the snib member via the force transfer mechanism may be initially high to overcome the keep force holding the snib member in the retracted position and may progressively decrease as the actuator element moves from the start position to the activated position. The degree or extent of displacement of the snib member may increase, however, as the actuator element moves from the start position to the activated position. The area of contact between the force output member and snib member preferably essentially comprises or approaches point contact or line contact. This reduces or minimizes friction between the respective contact surfaces or camming surfaces of the force output member and the snib member.

[0012] In a preferred embodiment, the actuator element is configured for generally linear movement between the start position and the activated position. The actuator element is preferably configured to be pressed by a user in the manner of a button for movement from the start position to the activated position to activate the privacy mode of the lock assembly. The actuator element is preferably in a captive relationship with the force transfer mechanism, which in turn is preferably in a captive relationship with the snib member. In this way, the actuator element may thereby provide a visual indication of the privacy mode status.

[0013] According to another aspect, the present invention provides a lock assembly for a door, comprising:

a handle mechanism having an inner door handle that is manually movable about a handle axis and an outer door handle that is manually movable about the handle axis;

a latch bolt that is movable between an extended position for latching in a recess of a door frame adjacent the door in or upon which the lock assembly is mounted, and a retracted position for unlatching the door;

a bolt retractor mechanism for moving the latch bolt from the extended position to the retracted position upon manual movement of the inner door handle or the outer door handle about the handle axis in a passage mode of the lock assembly; and

a privacy mode device of the invention according to any of the embodiments described above for locking the outer door handle of the lock assembly against rotation in a privacy mode.

Brief Description of Drawings

[0014] For a more complete understanding of the present invention and the advantages thereof, exemplary embodiments of the invention will be explained in detail in the following description with reference to the accompanying drawings, in which like reference signs designate like parts, and in which:

[0015] Fig. 1 is a first perspective view of a lock assembly according to a preferred embodiment of the invention as it would be assembled on a door, but without the door being shown, and with the privacy mode device in a non-activated state;

[0016] Fig. 2 is a second perspective view of the lock assembly of Fig. 1, with the privacy mode device in a non-activated state;

[0017] Fig. 3 is the first perspective view of the lock assembly in Fig. 1, shown with the privacy mode device in an activated state;

[0018] Fig. 4 is the second perspective view of the lock assembly in Fig. 1 and Fig. 2, with the privacy mode device shown in an activated state; [0019] Fig. 5 is a cross-sectional view through the lock assembly of Fig. 1 taken in the direction of arrows V-V in Figs. 3 and 4, showing the privacy mode device in the non-activated state;

[0020] Fig. 6 is a cross-sectional view of the lock assembly of Fig. 1 in direction of arrows V-V, with the actuator element moved from the start position into contact with the force transfer mechanism;

[0021] Fig. 7 is a cross-sectional view of the lock assembly of Fig. 1 in direction of arrows V-V, with the force transfer mechanism transferring an actuation force from the actuator element to the snib member as the actuator element moves from the start position to the activated position;

[0022] Fig. 8 is a cross-sectional view of the lock assembly of Fig. 1 in direction of arrows V-V, with the force transfer mechanism further transferring the force from the actuator element to the snib member as the actuator element moves from the start position to the activated position; and

[0023] Fig. 9 is a cross-sectional view of the lock assembly of Fig. 1 in direction of arrows V-V, showing the privacy mode device in the activated state.

[0024] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate particular embodiments of the invention and together with the description serve to explain the principles of the invention. Other embodiments of the invention and many of the attendant advantages of the invention will be readily appreciated as they become better understood with reference to the following detailed description.

Description of Embodiments

[0025] With reference firstly to Figs. 1 to 4 of the drawings, a preferred embodiment of a lock assembly 1 for installation in a door is illustrated. The lock assembly 1 is configured to operate in any one of a passage or latching mode, a privacy mode, and a deadlock mode. As will become apparent, the privacy mode is particularly relevant for the purposes of the present invention, but features relating to the deadlock mode will also be briefly identified later.

[0026] As can be seen in Figs. 1 and 2 of the drawings, the lock assembly 1 comprises a handle mechanism 10, a latch bolt 20, a bolt retractor mechanism 30, and a privacy mode device 40. The handle mechanism 10 includes an inner door handle 11 that is manually movable about a handle axis H and an outer door handle (not shown) that is manually movable about the handle axis H. The latch bolt 20 is movable via the handle mechanism 10 and bolt retractor mechanism 30 between an extended position protruding from a fascia plate 21 of a latch casing 22 (as seen in Fig. 1) for receipt in a recess of a strike plate provided on a door frame adjacent the door in or on which the lock assembly 1 is mounted, and a retracted position withdrawn into the casing 22 level with the fascia plate 21 for opening the door. In particular, the latch bolt 20 is movable by manually turning either the inner handle 11 or the outer handle (not shown) about the axis H.

The lock assembly 1 shown is configured to be mounted within a recess formed within the door, as will be understood by persons skilled in the art. When installed in the door (not shown), most parts of the lock assembly 1 (e.g. other than door handles 11, latch bolt 20, fascia plate 21, and key barrel) will be covered and/or enclosed by a housing including escutcheon plates P, shown in pale lines, which are to be securely mounted on the door.

[0027] The handle mechanism 10 includes a shaft 12 for transferring rotary motion of the inner handle 11 or outer handle (not shown) about the axis H to the bolt retractor mechanism 30 which in this case is essentially enclosed within the latch casing 22. As seen in Fig. 1 and Fig. 3 of the drawings, the handle mechanism 10 includes a torsion spring 13 for resiliently biasing the inner handle 11 about the handle axis H to the neutral or non-rotated position shown. Thus, when the inner handle 11 is manually turned about the axis H, it is turned against the bias of the torsion spring 13, which acts to return the handle 11 when released. Further, the handle mechanism 10 includes a hub member 14 that is non-rotatably fixed or keyed with respect to the shaft 12 and with respect to the outer handle (not shown).

[0028] The privacy mode device 40 includes an actuator element 41 in the form of a button for the manual input of an actuation force by a user for activating the privacy mode of the lock assembly 1. The actuator button 41 is configured for generally horizontal movement from a start position to an activated position when it is pressed by a user to activate the privacy mode of the lock assembly 1. The actuator element or button 41 is configured to seat within and project through an opening in the inner escutcheon plate P of the lock assembly 1 for operation by a user. The privacy mode device 40 further includes a snib member 42 configured for movement between an upper, retracted position (seen in Figs. 1 and 2) in a non-activated state, and a lower, extended position (seen in Figs. 3 and 4) when activated in the privacy mode. In this regard, the snib member 42 has a downwardly projecting nose 43, and is movable generally vertically between the upper, retracted position and the lower, extended position.

[0029] With reference to Figs. 2 and 4, it will be noted that the hub member 14 comprises a disc-like plate having a recess 15 formed in a periphery thereof. When the snib member 42 is moved vertically downwards from the retracted position to the extended position, the projecting nose 43 is received in and engages with the complementary recess 15 in the edge of the disc-like hub member 14. Because the hub member 14 is non-rotatably fixed or keyed with respect to the shaft 12 and with respect to the outer handle (not shown), this thereby locks the outer door handle of the lock assembly 1 against turning or rotation about the handle axis H. As will be explained in more detail later, however, turning the inner door handle 11 operates to disable this privacy function by moving the snib member 42 vertically upwards back to the retracted position, thereby permitting the door to be opened by the outer door handle again.

[0030] With reference now to Figs. 5 to 9 of the drawings, the privacy mode device 40 of this preferred embodiment will be illustrated and explained in more detail. In particular, it will be seen that the privacy mode device 40 includes a force transfer mechanism 44 for transferring the actuation force from the actuator element or button 41 to the snib member 42. In this regard, the force transfer mechanism 44 is configured and arranged to pivot about an axis X and includes a force input member 45 that extends from the pivot axis X for engagement by the actuator button 41 as the actuator button 41 is moved or pressed inwards from the start position to the activated position upon application of force F. The force transfer mechanism 44 also includes a force output member 46 that extends from the pivot axis X for engagement with the snib member 42. That is, the force output member 46 engages with the snib member 42 to move the snib member from the upper retracted position to the lower extended position as the actuator element or button 41 moves to the activated position. The force input member 45 is integrally formed with the force output member 46 for common pivoting about the pivot axis X. As such, the input and output members 45, 46 of the force transfer mechanism 44 form a lever arrangement or a lever mechanism that operates to generate mechanical advantage in imparting or transferring the actuation force F from the button 41 to the snib member 42. This is particularly useful because the snib member 42 is held or retained in the retracted position by a magnet of a solenoid 50. Thus, in the non-activated state, a certain threshold force is typically required to overcome or break the magnetic attraction holding the snib member 42 on the plunger of the keep solenoid 50 in its retracted position when the privacy mode is activated. [0031] In fact, it will be noted that the force transfer mechanism 44 in this embodiment of the privacy mode device 40 is configured with two force output members 46 which extend like prongs symmetrically of a central plane extending through the force input member 45, as is apparent from Figs. 1 to 4. For this reason, the force output member 46 shown in Figs. 5 to 9 does not have section lines, because it does not lie in the central section plane V-V as the force input member 45 does. For the purposes of the further description of the privacy mode device 40 reference will be made to the one force output member 46 that is shown in Figs. 5 to 9. It will be appreciated, however, that the same features and description apply to the second symmetrical force output member 46 of the force transfer mechanism 44.

[0032] Referring further to the drawing Figs. 5 to 9, the interrelationship between the actuator button 41, the force transfer mechanism 44, and the snib member 42 will be seen more clearly.

In the non-activated state of the privacy mode device 40 shown in Fig. 5, the actuator button 41 is in the start position and is spaced by a small gap g from a contact area Ai of the force input member 45 designed for engagement by the button 41. When the actuator button 41 is pressed by a user with a force F to activate the privacy mode, the button 41 is moved inwards into engagement with the contact area Ai of the force input member 45, as shown in Fig. 6. Further inward movement of the button 41 then acts to pivot the force input member 45 about the pivot axis X, as shown in drawing Figs. 7 and 8, as the actuator button 41 moves horizontally to the activated position. The contact area Ai between the button 41 and input member 45 is designed to approach point contact or line contact for minimizing friction between the button 41 and the input member 45. The contact area Ai is spaced at a distance di from the pivot axis X.

[0033] Because the input member 45 is integrally formed with the output member 46 for common pivoting about the axis X in the force transfer mechanism 44, as the actuator button 41 is pressed inwards from the start position to the activated position as shown in Figs. 6 to 8, the force output member 46 engages the snib member 42, thereby transferring the actuation force F from the actuator button 41 for moving the snib member 42 from the retracted position to the extended position. In this regard, respective contact surfaces of the force output member 46 and the snib member 42 form camming surfaces that are in engagement with one another at a contact area A _0. The contact area A ₀ is spaced at a distance d ₀ from the pivot axis X and the respective contact surfaces of the force output member 46 and the snib member 42 are configured such that this distance d ₀ varies as the output member 46 pivots. In particular, the contact area A ₀ moves progressively radially outwardly from the pivot axis X, thereby increasing the distance d ₀ , as the actuator button 41 is moved from the start position in Fig. 5 to the activated position in Fig. 8.

In this way, the force input member 45 and the force output member 46 are configured in the force transfer mechanism 44 as a lever arrangement and generate mechanical advantage as they impart or transfer the actuation force from the button 41 to the snib member 42. Thus, the force transferred or imparted to the snib member 42 by the output member 46 is in a ratio of di/d ₀ to the force F applied to the input member 45 by the button 41. When the contact area A ₀ is located closer to the pivot axis X at the initial actuation of the button 41, a larger mechanical advantage is generated to transfer or impart a larger force to the snib member 42 and this, in turn, is useful for overcoming a retaining force of the solenoid 50 holding the snib member 42 in the retracted position. As the contact area A ₀ moves progressively radially outwardly from the pivot axis X, thereby increasing the distance d ₀ , the mechanical advantage of the force transfer mechanism 44 reduces, although the degree of displacement of the snib member 42 increases.

[0034] As the actuator button 41 approaches the end of its path of travel, at which it is fully depressed and reaches the activated position, the force output member 46 has moved the snib member 42 vertically downwards from the retracted position and fully overcome the magnetic attraction of the keep solenoid 50. At this point, a force applied by a spring 48, such as a coil spring, acting on the snib member 42 also assists downward movement of the snib member 42 to its fully extended position, as seen in Fig. 9. At the extended position, the square projecting nose 43 is received in and engages with the recess 15 in the edge of the disc-like hub member 14 to activate the privacy mode in which the outer door handle (not shown) is locked against rotation about the handle axis H.

[0035] It will be noted that a distal or free end 47 of the force input member 45 extends into and resides within a recess or opening Oi formed within the actuator element 41, providing a captive relationship. Similarly, the force output member 46 extends through and is retained within a recess or opening 0 ₂ formed within the snib member 42, again ensuring a captive relationship. This can be clearly seen, for example, in Fig. 5 and Fig. 6. As a result, the actuator element or button 41 is not able to return to its start position when the snib member 42 is in the extended position with the projecting nose 43 in latched engagement with the recess 15 formed in the hub member 14. Instead, the actuator element or button 41 remains depressed and thereby provides a visual indication of the activated status of the privacy mode to a user on an inner side of the door. [0036] Briefly, it will be explained how turning the inner door handle 11 operates to disable this privacy function, thereby permitting the door to be opened by the outer door handle again. In this regard, we refer briefly back to Figs. 1 to 4 of the drawings, which show that the handle mechanism 10 includes a disc-like drive member 18 having an upwardly extending lobe 19 that presents an inclined upper surface. This lobe 19 and its inclined surface are configured and arranged for interaction with a tapered follower 49 provided on a side of the snib member 42 opposite the projecting nose 43. When the lock assembly 1 is in privacy mode, as is shown in Figs. 3 and 4, and the inner door handle 11 is turned slightly from the neutral position, the drive member 18 turns with the inner door handle 11 and moves the lobe 19 such that the follower 49 on the snib member 41 comes into engagement with the inclined upper surface of the lobe 19. Significantly, during this initial turning of the inner handle 11, the hub member 14 remains unmoved because the disc-like drive member 18 is movable within a dead angle (e.g. of about 15 to 25 degrees) relative to the hub member 14. Turning the inner door handle 11 through the full extent of this dead angle operates to move the lobe 19 further into contact with and against the follower 49, which acts to push the snib member 42 back upwards into its upper, retracted position. By designing the components of the lock assembly 1 appropriately, the projecting nose 43 of the snib member 42 disengages the hub member 14 just before the drive member 18 finishes moving through the dead angle. The upward movement of the snib member 42 back to the retracted position via interaction between the lobe 19 and the follower 49 acts to compress the spring 48 and pivots the output member 46 (and thus also the input member 45) back about the pivot axis X. Because of the captive relationship of the actuator button 41 with the force transfer mechanism 44, the button 41 is also returned to its start position shown in Fig. 5. In this regard, a spring bias may optionally act on the button 41 to assist return of the button 41 to its start position. It will be noted that drive member 18 includes a second upwardly extending lobe 19’ with an inclined surface. However, this lobel9’ only finds application when the lock assembly 1 is installed on an opposite edge of the door to that shown in Fig. 1, with the inner handle 11 arranged to turn in the anti-clockwise direction.

[0037] Referring again to Figs. 1 to 4 of the drawings, it will be noted that the lock assembly 1 includes a deadlock mode device 60 for activating and deactivating the deadlock mode of the lock assembly 1. The deadlock mode device 60 includes a key barrel 61 with cylinder cam 62, a deadlocking and privacy kick-off drive 63, a deadlocking lever 64, a deadlock solenoid 65, a deadlocking block 66 for blocking retraction of the latch bolt 20, and an anti-knock cam 67. Details of the operation of the deadlock mode device 60 are not described here. [0038] Although specific embodiments of the invention are illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternative and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are examples only and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

[0039] It will also be appreciated that in this document the terms "comprise", "comprising", "include", "including", "contain", "containing", "have", "having", and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms "a" and "an" used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms "first", "second", "third", etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.