THUMB-OPERATED MULTILATCH DOOR LOCK

Abstract: A multipoint lock assembly includes a central latch (20) and at least one remote latch (24) vertically spaced therefrom. The retraction of all the latches is controlled by a central latch driving mechanism (18) in response to a manual operation either of an exterior thumb-operated latch lever (32) or of an interior doorknob (48). A deadbolt (30) is also located proximate the central latch (20). The deadbolt (30) is controlled either by an externally accessed cylinder lock (68) or by a manual rotation of an interior-mounted thumb-turn (70). While the deadbolt (30) is extended, the thumb-operated latch lever (32) and the doorknob (48) are inoperable. At least one of the latches includes a latch trigger (66). This is tripped when the door is closed, allowing the latch (24) of which it is a part to assume a superextended position. When in this position the latch (24) cannot be forced into its retracted position unless the thumb-operated latch lever (32) or the doorknob (48) has been operated.

Description: THUMB-OPERATED MULTILATCH DOOR LOCK TECHNICAL FIELD This invention relates to door lock assemblies having a plurality of latches disposed at separate locations and that is retractable from a single location by a thumb lever. BACKGROUND ART Door lock assemblies for use on doors having a hinged edge and an opposite, swingable free edges have been known for some time. The need for security and improved sealing qualities led to the development of door lock sets having more than one independently operated latches, and these have also become well known. While the independently operated latches represent an improvement, they also exhibit some disadvantages. For example, persons in a hurry may not notice all the latches. Even if they do, they might not want to take the extra time required to set them all. Worn or damaged latches might suffer the same fate when persons feel they do not have time to make them work or to repair them. Whatever the reasons, the security and/or integrity sought will be, to some extent, compromised. Addressing these problems are door lock assemblies having more than one latch, each latch being retractable by manually operating a centrally located mechanism. These lock assemblies have become relatively common as well, but common problems attend them in that they can be difficult to assemble and install in a cost-effective manner. A remaining problem is the fact that, while many persons want door lock assemblies that match period or otherwise unique building or room designs, assemblies having thumb-operated multilatch door locks are reportedly not available for this application. While the prior techniques function with a certain degree of efficiency, none discloses the advantage of the improved thumb-operated multilatch door lock of the present invention as is hereinafter more fully described. DISCLOSURE OF INVENTION An object of the present invention is to provide a multilatch door lock for securing a door at a plurality of locations with latches that are all retractable from one location by a thumb-operated latch lever. Another object is to provide a thumb-operated multilatch door lock that is easy to assemble and install. An advantage of the present invention is that its assembly and installation are cost effective. A feature of the present invention is that it uses a popular and distinctive hardware element not previously associated with multilatch door locks. In realizing the aforementioned and other objects, advantages and features, the multilatch door lock includes a central latch that is slidable between retracted and extended positions. At least one remote latch is spaced apart from the central latch and is also slidable between retracted and extended positions. A thumb- operated latch lever is operably connected to the central latch and to the at least one remote latch to force each respective latch into its retracted position in response to a downward movement of the thumb-operated latch lever. A central latch driving mechanism is operably connected to the thumb- operated latch lever and to the central latch to force the central latch into its retracted position in response to a downward movement of the thumb-operated latch lever. A remote latch driving mechanism is operably connected to the at least one remote latch. An action bar operably connects the central latch driving mechanism to the at least one remote latch driving mechanism to communicate movement of the thumb-operated latch lever to the at least one remote latch driving mechanism. Each of the central and remote latches is resiliently biased toward its extended position. The at least one remote latch includes an upper and a lower remote latch. The at least one remote latch driving mechanism includes an upper remote latch driving mechanism and a lower remote latch driving mechanism. At least one of the latches includes a trigger mechanism to provide an additional latch extension when the latch trigger engages a strike. The objects and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS A more complete appreciation of the invention and many of the attendant advantages thereof may be readily obtained by reference to the following detailed description when considered with the accompanying drawings in which like reference characters indicate corresponding parts in all the views, wherein: FIGURE 1 is a perspective view indicating a representative configuration of a central latch a central latch driving mechanism, two remote latches and two remote latch driving mechanisms of a door lock assembly of the present invention; FIGURE 2 is a perspective view of the central latch driving mechanism, a thumb-operated latch lever and a D-handle; FIGURE 3 is an exploded perspective view of the central latch mechanism and a thumb-operated latch lever; FIGURE 4 is a perspective view of a remote latch of FIG. 1 shown mounted in a fragment of a door, the remote latch having a latch trigger and being shown in an extended position; FIGURE 5 is a perspective view of a remote latch of FIG. 1 shown mounted in a fragment of the door, the remote latch having a latch trigger and being shown in a superextended position; FIGURE 6 is a fractional view of the exterior of the door and shows a representative cylinder lock and D-handle; FIGURE 7 is a fractional view of the interior of the door and shows a representative thumb-turn and door knob; FIGURE 8 is a view similar to that of FIG. 6 and further including an exterior trim plate; and FIGURE 9 is a view similar to that of FIG. 7 and further including an interior trim plate. BEST MODE FOR CARRYING OUT THE INVENTION FIGURE 1 of the drawing is a perspective representation of a first subassembly, generally indicated by the reference numeral 12, of a preferred embodiment of the present invention. An elongate mounting plate 14 is provided with a plurality of mounting holes 16 to facilitate securing the mounting plate 14 to a free edge of a door (FIG's. 4 and 5) with any of a number of well-known fastening devices such as screws 17 (FIG's. 4 and 5). Secured to the mounting plate 14 is a central latch driving mechanism, generally indicated by the reference numeral 18. A central latch 20 extends from the central latch driving mechanism 18 and through the mounting plate 14. Also secured to the mounting plate 14 is an upper remote latch driving mechanism 22 having an upper remote latch 24 extending therefrom and through the mounting plate 14. Similarly secured to the mounting plate 14 is a lower remote latch driving mechanism 26 having a lower remote latch 28 extending therefrom and through the mounting plate 14. A deadbolt 30 also extends from the central latch driving mechanism 18 and through the mounting plate 14. The central latch driving mechanism 18 and the upper and lower remote latch driving mechanisms 22 and 26 are, as is well known, mountable within a mortise provided in a free edge of a door 34 (FIG's. 4 through 9). The mounting plate 14 is typically mountable within a shallow mounting plate channel 35 (FIG's. 4 and 5) in the free edge of the door by using screws 17 (FIG's. 4 and 5) or the like inserted through holes 16 provided in the mounting plate 14. FIGURE 2 shows the central latch driving mechanism 18 and a representative thumb-operated latch lever 32 and a D-handle 36. The D-handle 36 is attachable to a door, as shown in FIG. 6. FIGURE 3 is an exploded perspective representation of the central latch driving mechanism 18 and the thumb-operated latch lever 32. The central latch driving mechanism 18 is shown without a cover to illustrate a mechanism used to convert the lever action of the thumb lever 32 into a linear movement of the central latch 20 and of upper and lower action bars 38 and 40. A spindle 42, having an interior end, generally indicated by the reference numeral 44 and an exterior end, generally indicated by the reference numeral 46, extends through the central latch driving mechanism 18. The interior end 44 protrudes through the door (FIG. 7) so that a doorknob 48 (FIG's. 7 and 8), or the like, can be mounted thereon. The spindle 42 passes through an actuator 50, and its exterior end 46 is connected to a sector pinion 52. A double rack, or rack in slide, 54 is slidably disposed with its teeth 56 engaging the teeth 58 of the sector pinion 52. A downward movement of the thumb-operated latch lever 32 creates an upward movement of the rack in slide 54. This upward movement is resiliently opposed by a rack spring 60. The upward movement of the rack in slide 54 rotates the sector pinion 52 and the actuator 50. This retracts a central latch shaft 62 against the resilient force of the rack spring 60, which in turn retracts the central latch 20 to which it is attached. A slidably disposed connector plate 64 extends vertically from the central latch driving mechanism 18. The slidably disposed upper action bar 38 extends from an upper end of the connector plate 64 to the upper remote latch driving mechanism 22 (FIG. 1). The connector plate 64 and the upper action bar 38 operably connect the central latch driving mechanism 18 to the upper remote latch driving mechanism 22 to communicate movement of the thumb-operated latch lever to the upper remote latch driving mechanism 22 and thus to the upper remote latch 24 (FIG. 1). Movement of the thumb-operated latch lever 32 is communicated by a lower action bar 40 to the lower remote latch driving mechanism 26 and thus to the lower remote latch 28 (FIG. 1). Each of the central and remote latches is resiliently biased toward an extended position. The central latch driving mechanism 18, the central latch 20, the deadbolt 30, the upper and lower remote latches 24 and 28, the upper and lower latch driving mechanisms 22 and 26, the upper and lower action bars 38 and 40, and the mounting plate 14 cooperate to form the first subassembly 12. Being preassemblable, the first subassembly 12 facilitates time-, labor- and cost-effective manufacturing and installation. FIGURE 4 shows a fractional, perspective view of the upper free edge of the door 34 and includes a view of the upper remote latch 24. As seen in detail, the upper remote latch 24 includes a latch trigger 66. In the position shown, the upper remote latch 24 is shown in an extended position, as it would appear after the door 34 had been opened and the thumb-operated latch lever 32 had been released. The upper remote latch 24 is in a position that allows the door 34 to be closed, the slanted portion of the upper remote latch 24 promoting its smooth retraction as it is wiped across a striker plate (not shown) as the door 34 is being closed. The foregoing description of Figure 4 is also applicable to the lower remote latch 28. FIGURE 5 is similar to that of FIGURE 4. The upper remote latch 24, however, is shown in a superextended position. This is the position it is allowed to assume after the door has been closed and the latch trigger 66 has been tripped by that action. While in the superextended position, the upper remote latch 24 is typically prevented from being forced to its retracted position unless the thumb- operated latch lever 32 is depressed. The foregoing description of Figure 5 is also applicable to the lower remote latch 28. FIGURE 6 illustrates a central, exterior portion of the free edge of the door 34 and includes a view of the thumb-operated latch lever 32, of the D-handle 36 and of a key-operated lock, preferably a cylinder lock 68. The cylinder lock 68 controls the extension of the deadbolt 30 in response to the insertion and rotation of a key (not shown) therein. It will be appreciated by those skilled in the art that the cylinder lock 68 shown represents any of a number of well-known key-operated locks having a movable member capable of extending and retracting a deadbolt in response to a suitable motion of the key. Shown in FIGURE 7 is a view of the opposite side, that is, the interior side, of the portion of the free edge of the door 34 shown in FIGURE 6. The view shows the doorknob 48, torque applied to rotate the doorknob 48 being applied thereby to the spindle 42. The view also shows a thumb-turn 70, which is a counterpart of the cylinder lock 68 in that it controls the extension of the deadbolt 30 in response to a rotation of the thumb-turn 70. While the deadbolt 30 is extended, either by rotating a key in the exterior-mounted cylinder lock 68 or by rotating the interior-mounted thumb-turn 70, neither the thumb-operated latch lever 32 nor the doorknob 48 is operable to retract the central latch 20, the upper remote latch 24 or the lower remote latch 28. FIGURES 8 and 9 are similar to those of FIGURES 6 and 7 but further include views of exterior and interior trim plates 72 and 74 respectively. In FIGURE 8, the exterior trim plate 72 is shown mounted between the D-handle 36 and the door 34 and with the cylinder lock 68 extending through. In FIGURE 9, the interior trim plate 74 is shown mounted between the doorknob 48 and the door 34 and with the thumb-turn 70 extending through. While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and that various changes may be made without departing from the spirit and scope of the invention.

Claims: WHAT IS CLAIMED IS: 1. A thumb-operated multilatch door lock, comprising: a central latch being slidable between retracted and extended positions; at least one remote latch spaced apart from the central latch and being slidable between retracted and extended positions; an action bar interconnecting the central latch and the at least one remote latch; and a thumb-operated latch lever operably connected to the central latch and to the at least one remote latch to force each respective latch into its retracted position in response to a downward movement of the thumb-operated latch lever. 2. A thumb-operated multilatch door lock, comprising: a thumb-operated latch lever; a central latch slidable between retracted and extended positions; a central latch driving mechanism operably connected to the thumb- operated latch lever and to the central latch to force the central latch into its retracted position in response to a downward movement of the thumb-operated latch lever; at least one remote latch being slidable between retracted and extended positions; a remote latch driving mechanism operably connected to the at least one remote latch; and an action bar operably connecting the central latch driving mechanism to the at least one remote latch driving mechanism to communicate movement of the thumb-operated latch lever to the at least one remote latch. 3. The thumb-operated multilatch door lock as defined by claim 2, further including: an elongate mounting plate upon which the central latch driving mechanism and the at least one remote latch driving mechanism are mounted, the mounting plate being mountable to a free edge of a swingable door having an exterior side and an interior side, the mounting plate having apertures through which the central latch and the at least one remote latch can pass while they are extended. 4. The thumb-operated multilatch door lock as defined by claim 3 , wherein: the at least one remote latch includes an upper remote latch and a lower remote latch; and the at least one remote latch driving mechanism includes an upper remote latch driving mechanism and a lower remote latch driving mechanism, the upper and lower remote latches and the upper and lower remote latch driving mechanisms being respectively disposed above and below the central latch and the central latch driving mechanism. 5. The thumb-operated multilatch door lock as defined by claim 4, wherein the at least one action bar includes: an upper action bar operably connecting the central latch driving mechanism to the upper remote latch driving mechanism; and a lower action bar operably connecting the central latch driving mechanism to the lower remote driving mechanism. 6. The thumb-operated multilatch door lock as defined by claim 5, further including: a deadbolt slidable between a retracted position within the central latch driving mechanism and a position extending therefrom and through the mounting plate; a key-operated lock disposed within the door proximate the central latch driving mechanism, the key-operated lock having an exposed end formed to receive a key, the exposed end being accessible from the exterior side of the door, the key-operated lock effecting an extension and a retraction of the deadbolt when a key is inserted into the exposed end of the key-operated lock and rotated; a thumb-turn mounted on the interior side of the door and effecting an extension and retraction of the deadbolt when the thumb-turn is rotated; and a doorknob disposed on the interior side of the door and connected to the central latch driving mechanism to effect a retraction of the central and remote latches when the doorknob is rotated, neither the thumb-operated latch lever nor the doorknob being operable to retract the central or remote latches while the deadbolt is extended. 7. The thumb-operated multilatch door lock as defined by claim 6, wherein the central latch driving mechanism, the central latch, the deadbolt, the upper and lower remote latches, the upper and lower latch driving mechanisms, the upper and lower action bars, and the mounting plate cooperate to form a first subassembly. 8. The thumb-operated multilatch door lock as defined by claim 7, wherein each of the central and remote latches is resiliently biased toward its extended position. 9. The thumb-operated multilatch door lock as defined by claim 8, wherein the upper and lower remote latches each have a retracted, an extended and a superextended position, the upper and lower remote latches each further including a latch trigger mounted therein, the latch triggers releasing the remote latches to extend to their superextended positions when the door is fully closed. 10. The thumb-operated multilatch door lock as defined by claim 9, further including a D-handle disposed proximate the thumb-operated latch lever and mounted on the exterior surface of the door. 11. A thumb-operated three-point door lock comprising: a thumb-operated latch lever; a central latch slidable between retracted and extended positions; a central latch driving mechanism operably connected to the thumb- operated latch lever and to the central latch to force the central latch into its retracted position in response to a downward movement of the thumb-operated latch lever; an upper remote latch being slidable between retracted and extended positions; an upper remote latch driving mechanism operably connected to the upper remote latch; an upper action bar operably connecting the central latch driving mechanism to the upper remote latch driving mechanism to communicate movement of the thumb-operated latch lever to the upper remote latch; a lower remote latch being slidable between retracted and extended positions; a lower remote latch driving mechanism operably connected to the lower remote latch, each of the central and remote latches being resiliently biased toward its extended position, each of the upper and lower remote latches having a retracted, an extended and a superextended position, the upper and lower remote latches each further including a latch trigger mounted thereto, the latch triggers releasing the remote latches to extend to their superextended positions when the door is fully closed; a lower action bar operably connecting the central latch driving mechanism to the lower remote latch driving mechanism to communicate movement of the thumb-operated latch lever to the lower remote latch; an elongate mounting plate upon which the central latch driving mechanism and the at least one remote latch driving mechanism are mounted, the mounting plate being mountable to a free edge of a swingable door having an exterior side and an interior side, the mounting plate having apertures through which the central latch and the at least one remote latch can pass while they are extended; a deadbolt slidable between a retracted position within the central latch driving mechanism and a position extending therefrom and through the mounting plate; a key-operated lock disposed within the door proximate the central latch driving mechanism, the key-operated lock having an exposed end formed to receive a key, the exposed end being accessible from the exterior side of the door, the key-operated lock effecting an extension and a retraction of the deadbolt when a key is inserted into the exposed end of the key-operated lock and rotated; a thumb-turn mounted on the interior side of the door and effecting an extension and retraction of the deadbolt when the thumb-turn is rotated; and a doorknob disposed on the interior side of the door and connected to the central latch driving mechanism to effect a retraction of the central and remote latches when the doorknob is rotated, neither the thumb-operated latch lever nor the doorknob being operable to retract the central or remote latches while the deadbolt is extended, and the central latch driving mechanism, the central latch, the deadbolt, the upper and lower remote latches, the upper and lower latch driving mechanisms, the upper and lower action bars, and the mounting plate cooperating to form a first subassembly.

Inventors: DAVIS EUGENE R III, DAVIS, EUGENE, R., III
Applicants: THERMA TRU CORP, THERMA-TRU CORPORATION
Application year: 2000
Main classification: E05B59
IPC codes: E05B7, E05B53, E05B63, E05C9