1. Field of the Invention
This invention relates to interconnected locks. Interconnected locks are locks in which the outside of the door appears to have two separate conventional locks comprising a latchbolt lock mechanism on the bottom and a deadbolt lock mechanism on the top. On the inside of the door, however, the latchbolt and deadbolt are interconnected so that rotating the inner handle automatically retracts the deadbolt as the latchbolt is retracted.
2. Description of Related Art
From the locked outer side, a door fitted with an interconnected lock appears to have two separate conventional locks. Typically the upper lock appears to be a conventional deadbolt operated by a key to drive a deadbolt and the lower lock appears to be a standard cylindrical or tubular lock that drives a latchbolt. On the inside however, the two locks are interconnected.
A principal advantage of interconnected locks is that they simplify exiting a locked area. With separately installed deadbolt and latchbolt locks, exiting a locked area requires two motions—rotating a thumb turnpiece to retract the deadbolt and rotating the inner handle to retract the latchbolt. To exit through an interconnected lock requires only a single motion. Rotating the inner handle of the interconnected lock simultaneously retracts the deadbolt and the latchbolt.
The convenience provided by the interconnection described above, however, is a security disadvantage for conventional prior art interconnected locks. If a vandal is able to break off or remove the outer handle it may be possible to gain access from outside the locked area through the failed latchbolt lock to the inside spindle or other latchbolt lock components turned by the inner handle. In such a case, the interconnection of a prior art interconnected lock between the latchbolt lock components and the deadbolt lock will allow the vandal to retract the deadbolt as well as the latchbolt by manipulating the components of the interconnected lock on the inner side of the door. When the deadbolt and latchbolt are separately installed, failure of the latchbolt lock mechanism does not affect the security of the deadbolt lock mechanism.
Because latchbolt locks, such as cylindrical locks and tubular locks, are generally less resistant to attack than deadbolt locks, the overall security of prior art interconnected locks is less than for an installation using a completely separate and independent deadbolt and latchbolt lock. There is a need for an interconnected lock design where the deadbolt and latchbolt lock mechanisms interact to provide the advantages of an interconnected lock, yet which is as secure as separately installed and independently operated deadbolt and latchbolt lock mechanisms.
Because of the ease with which a locked area may be exited, interconnected locks are often installed for use by the elderly or infirm. The speed of operation and simplicity of use of the interconnected lock is particularly valuable in an emergency, such as a fire. The benefits may be greatest when the occupant of the locked room is elderly and/or has reduced mental capabilities, as they may not remember to rotate the thumb turnpiece of a separately installed deadbolt before attempting to exit via the locked door.
However, these advantages for the elderly and mentally disabled are offset by the current design of interconnected locks for those who are physically disabled, weak, injured or infirm. Conventional interconnected locks simultaneously retract the latchbolt and the deadbolt as the inner handle is turned. The simultaneous operation of the latchbolt and deadbolt mechanisms requires more torque than operating these elements separately. The elderly and infirm may not be able to easily produce the increased torque required, making the interconnected lock more difficult to operate by those for whom the lock offers some of the greatest advantages.
The use of lever handles to provide more handle torque, as used in public buildings to improve access by the disabled, exacerbates the security disadvantage described above because a vandal can use a lever handle to produce more torque and break the latchbolt lock portion of an interconnected lock. Accordingly, there is a need for an interconnected lock that does not require more torque to operate than the torque required to separately operate a conventional deadbolt or a conventional cylindrical lock.
Another disadvantage of conventional interconnected locks is that they simplify the process of exiting a locked area, but not the process of locking the door. The deadbolt portion of the interconnected lock must still be separately locked by rotating the thumb turnpiece on the inside of the door after the door is closed. Often, this is not done. It would be desirable for an improved interconnected lock design to allow the deadbolt to be extended as easily as it is retracted.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide an interconnected lock that is more secure than conventional interconnected locks, particularly when lever handles are installed.
It is another object of the present invention to provide an interconnected lock that requires less handle torque to operate the lock than is required to operate conventional interconnected locks that simultaneously retract the latchbolt and the deadbolt.
A further object of the invention is to provide an interconnected lock that simplifies the process of locking by extending the deadbolt with the inner handle, as well as retracting it.
It is yet another object of the present invention to provide an interconnected lock that allows the state of the lock to be quickly determined from the position of the inner handle.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The above and other objects, which will be apparent to those skilled in the art are achieved in the present invention which is directed to an independently interactive interconnected lock having a latchbolt lock mechanism, a deadbolt lock mechanism and an interconnecting mechanism connected between the latchbolt and the deadbolt lock mechanisms.
The latchbolt lock mechanism is mountable in a first bore through a door, and the deadbolt lock mechanism is mountable in a second bore through the door offset from the first bore. The latchbolt lock mechanism includes a latchbolt and an outer handle that moves the latchbolt between latched and unlatched positions.
The deadbolt lock mechanism is mountable in a second bore through the door offset from the first bore. The deadbolt lock mechanism includes a deadbolt movable between bolted and unbolted positions.
The interconnecting mechanism is operable by an inner handle to drive the latchbolt between the latched and unlatched positions and the deadbolt between the bolted and unbolted positions. The inner handle is movable between an up position, an intermediate position and a down position. The interconnecting mechanism drives the deadbolt to the bolted position when the inner handle is moved to the up position. It drives the deadbolt to the unbolted position when the inner handle is moved to the intermediate position, and it drives the latchbolt to the unlatched position when the inner handle is moved to the down position.
In the preferred design of the independently interactive interconnected lock, the inner handle drives the deadbolt from the bolted position to the unbolted position as the inner handle moves from the up position to the intermediate position and the inner handle drives the latchbolt from the latched position to the unlatched position as the inner handle moves from the intermediate position to the down position.
An aspect of the invention is that the interconnecting mechanism disconnects the latchbolt lock mechanism from the deadbolt lock mechanism when the inner handle is moved to the up position. Thus, manipulation of the latchbolt lock mechanism from the outside to move the latchbolt to the unlatched position does not move the deadbolt to the unbolted position.
Another aspect of the invention is that the inner handle and outside handle rotate on different axes of rotation. The axis of rotation of the outer handle is through the first bore and the axis of rotation of the inner handle is located between the first and second bores, which correspond to the positions of the latchbolt and deadbolt mechanisms.
In the most highly preferred embodiment of the invention, the interconnecting mechanism includes two deadbolt drivers, which may be deadbolt gears. The two deadbolt drivers are offset from the axis of rotation of the outside handle by distances that correspond to two industry standard bore offset distances for installing separate latchbolt locks and deadbolt locks. This allows the lock to be used with existing installations, pre-bored doors and templates and tools for boring doors at either of the industry standard offset distances.
In the preferred design of the invention the inner handle drives a handle gear that is a partial gear. The handle gear engages and drives at least one deadbolt gear as the inner handle moves from the up position to the intermediate position to drive the deadbolt from the bolted to the unbolted position. The handle gear does not drive the deadbolt gear as the inner handle moves from the intermediate position to the down position. A reengagement spring acts to apply a force to reengage the deadbolt gear and the partial handle gear as the inner handle moves through the intermediate position when moving from the down position to the up position.
The deadbolt gear drives two secondary deadbolt gears preferably via an intermediate deadbolt gear. The two secondary deadbolt gears form two alternative deadbolt drivers offset from an axis of rotation of the outside handle by distances that correspond to two industry standard bore offset distances.
In order to drive the latchbolt lock mechanism independently of the deadbolt lock mechanism, the inner handle drives a first latchbolt lever with lost motion from a latchbolt extended position to a latchbolt retracted position. The inner handle does not drive the first latchbolt lever as the inner handle moves from the up position to the intermediate position during the lost motion interval. The inner handle begins to drive the first latchbolt lever to retract the latchbolt as the inner handle moves from the intermediate position to the down position.
The latchbolt lever drives a latchbolt slide vertically. The latchbolt slide, in turn, drives a second latchbolt lever connected to a latchbolt hub, which is connected to drive the latchbolt lock mechanism and retract the latchbolt. To reduce friction between the first latchbolt lever and the latchbolt slide, the latchbolt slide includes a roller at the point of contact between the first latchbolt lever and the latchbolt slide.
The latchbolt slide preferably engages the second latchbolt lever with a rotating bearing having a slide channel formed therein. The rotating bearing rotates in the latchbolt slide and the second latchbolt lever slides in the slide channel of the rotating bearing.
In an alternative embodiment of the invention, the handle gear interferes with the latchbolt hub when the inner handle is in the up position to prevent the outside handle from turning when the inner handle is in the up position and the deadbolt is extended.
The invention is also directed to a bored lock interconnecting mechanism for driving a latchbolt lock mechanism in a first bore of a door and a deadbolt lock mechanism in a second bore of the door. The interconnecting mechanism includes a handle gear rotated by an inner handle movable between an up position, an intermediate position and a down position. At least one deadbolt gear is connected to drive the deadbolt lock mechanism between bolted and unbolted positions.
The deadbolt gear is driven by the handle gear as the inner handle moves between the up position and the intermediate position and is not driven by the handle gear as the inner handle moves between the intermediate position and the down position.
A latchbolt hub is connected to drive the latchbolt lock mechanism between latched and unlatched positions. The latchbolt hub is driven by the handle gear with lost motion such that the latchbolt hub is not driven by the handle gear as the inner handle moves between the up position and the intermediate position and the latchbolt hub is driven by the handle gear as the inner handle moves between the intermediate position to the down position.
The features of the invention believed to be novel and the elements characteristic of the invention are set forth with particularity in the appended claims. The figures are for illustration purposes only and are not drawn to scale.
The invention itself, however, both as to organization and method of operation, may best be understood by reference to the detailed description which follows taken in conjunction with the accompanying drawings in which:
a is a right side elevational view of an interconnected lock according to the prior art showing the lock installed in a portion of a door. The view is from the edge of the door and shows that the inner handle on the left rotates on the same axis as the outer handle on the right. The thumb turnpiece required for a prior art interconnected lock is also shown.
In describing the preferred embodiment of the present invention, reference will be made herein to
Referring to
The latchbolt lock mechanism 14 includes an outer handle 22 and an outer portion 24 mounted on the outer surface 26 of door 20. The latchbolt lock mechanism 14 is a substantially conventional bored lock, such as a cylindrical lock or tubular lock, that includes a conventional lock core (not shown) installed in a first bore 28 (see
The deadbolt lock mechanism 16 includes a key operated outer portion 32 that is conventionally installed in a second bore 34 (see
a shows a prior art installation of an interconnecting mechanism 10′ operating a deadbolt lock mechanism 16 and a latchbolt lock mechanism 14. It can be seen that the interconnected lock of this invention and an interconnected lock of the prior art appear from the outside to be a conventional separately installed deadbolt 16 and latchbolt 14. The outer portions of the deadbolt and latchbolt lock mechanisms, as well as the latchbolt and deadbolt themselves are the same in
However, on the inside of the door, the present invention, as seen in
In interconnected locks of the prior art, as exemplified in
As will be described in detail below, by placing the inner handle on a different axis from the rest of the latchbolt lock mechanism 14 and outer handle 22, it is possible to operate the latchbolt lock mechanism and deadbolt lock mechanisms independently, yet allow them to interact as necessary. This independent operation improves security by decoupling the inner handle 12 and the deadbolt lock mechanism 16 from the outer handle 22 and the latchbolt lock mechanism 14. The deadbolt is isolated from the inside components of the latchbolt lock mechanism and the hub 80 (see
Even if the outer handle 22 is broken off or removed, and even if the inside components of the latchbolt lock mechanism are manipulated from the outside to retract the latchbolt, the decoupling design of the present invention prevents the deadbolt from being simultaneously retracted with the latchbolt.
In
As the handle continues to move from the intermediate position 42 to the down position 44, the latchbolt 30 is retracted. As can be seen in
As the inner handle moves between the up position 40 and the intermediate position 42, the deadbolt moves between the bolted and unbolted positions. Unlike prior art interconnected locks, as in
In addition to improving security, the design of this invention decreases the maximum torque required to operate the lock mechanism. Because the deadbolt and latchbolt retraction occur at different sectors of the inner handle's rotation, at no point is it necessary to simultaneously drive both the deadbolt and the latchbolt.
The torque required to operate the handle as it moves from the up position 40 to the intermediate position 42 depends solely upon the friction and spring pressure required to operate the deadbolt lock mechanism. The torque required to rotate the inner handle from the intermediate position 42 to the down position 44 depends solely upon the design of the latchbolt lock mechanism. Accordingly, unlike the prior art which retracts both the deadbolt and latchbolt simultaneously, the interconnected lock of the present invention does not increase the torque required to operate the lock above that required for a separate deadbolt or latchbolt lock mechanism.
In addition to the security advantage, the simplified deadbolt extension advantage and the reduced torque advantage, the present invention makes it much easier to verify that the door is locked. Those who have poor eyesight, and those who are far away from the door can easily see if the door is properly bolted simply by referring to the position of the inner handle.
The details of the interconnecting mechanism 10 are shown in
The interconnecting mechanism in
Referring to
The handle gear 52 drives a deadbolt gear train whenever the geared portion engages that gear train, but does not drive the deadbolt gear train when the smooth sector reaches the point of geared contact with the deadbolt gear train.
The deadbolt gear train is composed of a primary deadbolt gear 54, an intermediate deadbolt gear 56, mounted on the same shaft as the primary deadbolt gear, and a pair of secondary deadbolt gears 58, 60 that lie above and below the primary and intermediate deadbolt gears.
As the inner handle 12 moves from the up position in
As the inner handle moves from up to level, from
This design allows the interactive mechanism to be installed with either of the two standard offsets between the deadbolt and latchbolt and permits the use of standard templates and fixtures. The interconnected lock can be used in preexisting installations with preexisting standard offset bores for the latchbolt and deadbolt.
Accordingly, the outer portion of the deadbolt lock mechanism will be axially aligned with the axis of rotation of secondary deadbolt gear 58 or secondary deadbolt gear 60. The slot in the center of the axis of deadbolt gear 58 or deadbolt gear 60 receives a shaft from the deadbolt lock mechanism. The rotation of the deadbolt gear train as the inner handle moves between the intermediate and up positions will drive the deadbolt between the bolted and unbolted positions. Raising the inner handle extends the deadbolt and lowering the handle retracts it.
The smooth segment portion of the handle gear 52 and the partial gear design of the primary deadbolt gear 54 ensure that rotation of the inner handle between the intermediate position and the down position has no effect on the deadbolt lock mechanism.
Because the primary deadbolt gear 54 disengages from the handle gear 52 as the smooth portion of the handle gear reaches the point of contact, a reengagement spring 64 is provided. As can be seen in
The reengagement spring 64 provides a rotation torque to the primary deadbolt gear to ensure that the first tooth on the partial portion of the primary deadbolt gear 54 properly reengages the first tooth in the toothed sector of the handle gear 52 as the inner handle is rotated from below the intermediate position past the intermediate position toward the up position.
During the operation of the deadbolt lock mechanism described above, the latchbolt is unaffected. To operate the latchbolt lock mechanism a first latchbolt lever 66 is mounted to freely rotate on the same axis as the handle gear 52. The handle gear 52 drives the first latchbolt lever 16 with a lost motion interaction such that rotating the handle gear 52 from the position in
However, as the handle gear reaches the position in
As the inner handle moves past the intermediate position to the down position, and the first latchbolt lever moves from the latchbolt extended position in
The latchbolt slide 72 drives a second latchbolt lever 78, which rotates a latchbolt hub 80. The latchbolt hub 80 includes a notch 82 and a tab 84 that engage and drive the latchbolt lock mechanism to retract the latchbolt as the inner handle moves from the intermediate position to the down position.
The latchbolt slide 72 drives the second latchbolt lever 78 with a rotating bearing 86 having a slide channel 88 formed therein. As the slide moves down, the distance between the axis of rotation 62 of the outer handle and the bearing 86 changes. The second latchbolt lever slides axially in the slide channel 88 of the rotating bearing 86 to accommodate this changing distance. This design provides a solid feel to the interconnected lock while simultaneously reducing friction.
The latchbolt hub 80 is biased to bring the latchbolt slide 72 back to its initial position with spring 90, which also biases the inner handle back toward the intermediate position.
In the alternative design shown in
As can be seen by comparing
It will be seen from the description above that the objectives of this invention have been achieved. The deadbolt lock mechanism and latchbolt lock mechanism operate independently, yet they interact as desired for an interconnected lock. Security has been improved, handle torque has been reduced as compared to prior art interconnect locks, and deadbolt extension has been simplified, allowing the removal of the thumb turnpiece of prior art locks. Finally, the status of the lock can easily be determined by visual inspection of the position of the inner handle.
While the present invention has been particularly described, in conjunction with a specific preferred embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. It is therefore contemplated that the appended claims will embrace any such alternatives, modifications and variations as falling within the true scope and spirit of the present invention.