Patent Application
20220333414
The present disclosure relates to door locks and latches intended for child safety, and in particular to locks and latches for mounting on a residential door top. In one embodiment, a door top sliding lock provides increased resistance to opening due to shaking of the door.
A variety of child-resistant door locks and latches are known for deterring small children from opening residential doors. Preferably a child-resistant door lock should be easy for an adult to operate but difficult or impossible for a child to operate.
One example of a child-resistant door lock is a door top sliding child lock mechanism sold by Predictable Solutions, LLC under the trademark GLIDELOK®. The GLIDELOK® door lock mechanism is suitable for use on most residential doors that swing on hinges. The GLIDELOK® door lock mechanism comprises a metal body for mounting on a door top and a metal peg for mounting on the door jamb or door frame. The GLIDELOK® body comprises a channel configured to slidably mount on a door top with the web of the channel resting on the door top and flanges of the channel hanging from the web on either side of the door. A lock plate extends horizontally from one flange of the channel, typically on the jamb side of the door, and defines a straight-sided U-shaped slot extending from a lateral edge and running parallel to the face of the door. The GLIDELOK® peg is rigidly mounted to the door jamb or door frame such that, when the GLIDELOK® body is positioned on the door top, the body can slide along the door top between a locked position, wherein the peg is disposed within the U-shaped slot thereby preventing the door from moving away from the peg (i.e., effectively locking the door), and an unlocked position, wherein the peg is disposed outside the U-shaped slot thereby allowing the door to move away from the peg (i.e., effectively unlocking the door). The GLIDELOK® mechanism is thus very simple for an adult to operate from either side of the door by merely pushing the exposed flange to slide the body back and forth along the door top between the locked position and the unlocked position and vice-versa. A small child cannot operate the GLIDELOK® mechanism because they are not tall enough to reach the mechanism on the door top to slide it. The GLIDELOK® mechanism can be adapted for doors of exceptional height or adults of lesser stature by attaching extension rods to the flanges of the GLIDELOK® mechanism. The extension rods hang down along each side of the door to a height where the adult can reach them to slide the GLIDELOK® body while a small child cannot reach them.
The existing GLIDELOK® mechanism is a simple and effective child-resistant lock; however, under some unusual circumstances the lock may be defeated (i.e., inadvertently unlocked) by repeated pushing, striking or shaking of the door. It is believed that sometimes pushing against a door locked with the GLIDELOK® mechanism causes the peg to exert a small lateral force against the lock plate on the door top due to the slight angle present between the door frame and the partially opened door (i.e., it has moved in a slight arc around the hinges). The lateral force may inadvertently move the lock plate a small distance. Normally, such small movement would be inconsequential. However, with repeated pushing, shaking or striking of the locked door, the succession of small lateral movements may progressively move (i.e., “walk”) the lock plate across the door top until the peg disengages from the U-shaped slot. At this point, the GLIDELOK® would no longer prevent the door from opening. In other cases, the lateral walking of the lock plate may be the cumulative effect of successive random movements of the lock plate caused by shaking the door against the peg rather than from uniform lateral forces. But the end result may be the same, i.e., the lock plate walks, i.e., moves laterally, until the peg disengages from the U-shaped slot, and the door can then be opened.
A need therefore exists, for an improved sliding door top lock that is resistant to unintended movement caused by repeated shaking or striking of the door, while remaining simple to install and operate by adults.
In one aspect, a door top sliding child safety lock mechanism is disclosed for mounting on a door assembly comprising a door hingedly connected to a door frame. The safety lock mechanism comprises a body slidably mountable on a door top of a door, the body including a channel section and a locking plate. The channel section includes a web extending between a first flange and a second flange, the second flange is disposed parallel to the first flange. The lock plate extends perpendicularly from an outer face of the first flange and defines a locking slot extending between an open end disposed along a lateral edge of the lock plate to a closed end along a slot axis running parallel to the flanges. The lock plate further defines an interlock cut-out formed along a distal edge, relative to the first flange, of the locking slot, wherein a first width WG measured perpendicular to the slot axis at the interlock cut-out is greater than a second width WL. measured perpendicular to the slot axis in a region of the lock plate that is laterally intervening between the interlock cut-out and the open end of the locking slot. A peg is mountable to a door frame and configured to slide through the open end of the locking slot and between the proximal and distal edges of the locking slot.
In one embodiment, the interlock cut-out comprises an arcuate notch formed along the distal edge of the locking slot.
In another embodiment, the interlock cut-out comprises a rectangular notch formed along the distal edge of the locking slot.
In still another embodiment, the interlock cut-out comprises a rectangular notch formed along the distal edge of the locking slot and a leading incline portion disposed towards the open end of the locking slot.
In yet another embodiment, the lock plate further comprises an anti-walk feature formed along the distal edge of the locking slot. The anti-walk feature is a profile that biases the lock plate laterally towards the open end of the locking slot when pushed against the peg.
In a further embodiment, the anti-walk feature is a portion of the interlock cut-out.
In a still further embodiment, the anti-walk feature is separate from the interlock cut-out.
In another aspect, a safety lock mechanism is disclosed, comprising a body slidably mountable on a door top of a door assembly comprising a door hingedly connected to a door frame, the door being rotatable relative to the door frame about a hinge axis, the door top extending between a frame-side face of the door and an open-side face of the door. The body comprises a channel section including a web extending between a first flange and a second flange, the second flange being disposed parallel to the first flange. The channel section is configured so that the web can rest on the door top with the first flange depending from the web adjacent to the frame-side face of the door and the second flange depending from the web adjacent to the open-side face of the door. The frame-side and open side faces of the door define a lateral direction parallel thereto. A lock plate extends perpendicularly from an outer face of the first flange, the lock plate configured to extend horizontally away from the frame-side face of the door when the body is mounted on the door top. The lock plate defines a locking slot extending between an open end disposed along a first lateral edge of the lock plate to a closed end along a slot axis parallel to the frame-side face of the door. The lock plate further defines an interlock cut-out formed along a distal edge, relative to the first flange, of the locking slot, wherein a first width WG measured perpendicular to the slot axis at the interlock cut-out is greater than a second width WL measured perpendicular to the slot axis in a region of the lock plate that is laterally intervening between the interlock cut-out and the open end of the locking slot. A peg is configured to slide into the locking slot and fixedly mountable to a portion of the door frame adjacent to a frame-side edge of the door top to extend downward from the door frame. When the body is positioned on the door top of a door adjacent the door frame and the peg is fixedly mounted on the door frame with the peg aligned with the slot axis, the lock mechanism can move between an unlocked configuration and a locked configuration by sliding the body laterally on the door relative to the peg. When the lock mechanism is in the unlocked configuration, the peg is disposed outside the locking slot of the lock plate, thereby allowing the body to rotate around the hinge axis away from the peg and allowing the door to rotate away from the door frame. When the lock mechanism is in the locked configuration, the peg is disposed within the locking slot of the lock plate, thereby restricting the body from rotating around the hinge axis away from the peg and restricting the door from rotating away from the door frame. The lock mechanism can move between the locked configuration and an interlocked configuration by rotating the body relative to the peg around the hinge axis. When the lock mechanism is in the locked configuration, the peg is not disposed within the interlock cut-out of the lock plate, thus allowing the body to slide laterally far enough to release the peg from the locking slot. When the lock mechanism is in the interlocked configuration, the peg is at least partially disposed within the interlock cut-out, thereby restricting the body from sliding laterally far enough to release the peg from the locking slot.
In one embodiment, the lock mechanism cannot move directly from the unlocked configuration into the interlocked configuration.
In another embodiment, the lock plate further comprises an anti-walk feature formed along the distal edge of the locking slot, the anti-walk feature being a profile that biases the lock plate laterally towards the open end of the locking slot when pushed against the peg.
In yet another aspect, a door top sliding child safety lock mechanism comprises a body slidably mountable on a top of a door, the body including a channel section and a locking plate. The channel section includes a web extending between a first flange and a second flange, the second flange being disposed parallel to the first flange. The lock plate extends perpendicularly from an outer face of the first flange and defines a locking slot extending between an open end disposed along a lateral edge of the lock plate to a closed end along a slot axis running parallel to the flanges. A peg is mountable to a door frame and configured to slide through the open end of the locking slot and between the proximal and distal edges of the locking slot. The lock plate further defines an anti-walk feature formed along one side of the locking slot, the anti-walk feature being a profile that biases the lock plate laterally towards the open end of the locking slot when pushed against the peg.
In one embodiment, the anti-walk feature comprises a notch formed along a distal edge of the locking slot relative to the first flange, and the distal edge of the notch slopes towards the first flange viewed in a direction towards the open end of the locking slot.
In another embodiment, the lock plate further defines an interlock cut-out, the interlock cut-out being a profile formed along a distal edge of the locking slot. A first width WG measured perpendicular to the slot axis at the interlock cut-out is greater than a second width WL measured perpendicular to the slot axis in a region of the lock plate that is laterally intervening between the interlock cut-out and the open end of the locking slot.
In yet another embodiment, the interlock cut-out comprises an arcuate notch formed along the distal edge of the locking slot.
In still another embodiment, the interlock cut-out comprises a rectangular notch formed along the distal edge of the locking slot.
In a further embodiment, the interlock cut-out comprises a rectangular notch formed along the distal edge of the locking slot and a leading incline portion disposed towards the open end of the locking slot.
For a more complete understanding, reference is now made to the following description taken in conjunction with the accompanying Drawings in which:
Referring now to the drawings, wherein like reference numbers are used herein to designate like elements throughout, the various views and embodiments of a door top sliding child safety lock are illustrated and described, and other possible embodiments are described. The figures are not necessarily drawn to scale, and in some instances the drawings have been exaggerated and/or simplified in places for illustrative purposes only. One of ordinary skill in the art will appreciate the many possible applications and variations based on the following examples of possible embodiments.
Referring to
Referring in particular to
The body 102 of the lock mechanism 100 further includes a lock plate 116 extending perpendicularly from an outer face of the first flange 110. As best seen in
Referring now in particular to
The lock plate 116 of the body 102 is further configured to define an interlock cut-out 130 formed on the distal edge 132 of the locking slot 118. The distal edge 132 is the laterally-oriented edge of the locking slot 118 farthest from the first flange 110, whereas the laterally-oriented edge closest to the first flange is denoted as the proximal edge 134. The interlock cut-out 130 is a profile enlarging the width of the locking slot 118 (measured perpendicular to the slot axis 126) in a region of the locking plate 116 that is laterally spaced apart from the open end 120. In other words, between the interlock cut-out 130 and the slot open end 120, there is always portion of the locking slot 118 of narrower width than the interlock cut-out.
The interlock cut-out 130 does not contact the peg 104 during normal operation (i.e., lateral sliding) of the body 102 for locking and unlocking the lock mechanism 100 with the door 202 closed adjacent the door jamb 214. However, when the door 202 is moved ajar (i.e., slightly open in the circumferential direction around the door hinges) with the lock mechanism 100 in the locked configuration, the peg 104 moves into the interlock cut-out 130 and the lock mechanism moves from the locked configuration to the interlocked configuration. The difference between the locked configuration and the interlocked configuration of the lock mechanism 100 is very distinct: When the lock mechanism 100 is in the locked configuration, the peg 104 mechanically blocks rotational movement of the body 102 (i.e., around the hinge axis) but the peg does not mechanically block lateral movement of the body (i.e., sliding on the door 202) into the unlocked position, and thus the body is held in the locked position only by friction between the body and the door and peg. In contrast, when the lock mechanism 100 is in the interlocked configuration, the peg 104 mechanically blocks both rotation movement of the body 102 and lateral movement of the body into the unlocked position because of mechanical interference between the edge of the interlock cut-out 130 and the peg. Thus, when in the locked configuration, the body 102 can slide into the unlocked position if enough lateral force is applied to overcome friction, whereas in the interlocked configuration, the body will not slide into the unlocked position regardless of the lateral force applied because the peg is mechanically trapped within the interlock cut-out 130.
In the embodiment of
The lock plate 116 of the body 102 may be further configured to define an anti-walk feature 136 provided along one side of the locking slot 118. The anti-walk feature 136 does not contact the peg 104 during normal (i.e., sliding) motion for locking and unlocking of the lock mechanism with the door 202 closed adjacent the door jamb 214. However, when the closed door 202 is moved ajar, as when shaken or pushed when the lock mechanism 100 is engaged, the anti-walk feature 136 can contact the peg 104. The anti-walk feature 136 biases the lock plate 116 laterally towards the open end 120 of the locking slot 118 (i.e., the biasing force on the locking plate is in the direction of the open end) each time the peg 104 contacts the anti-walk feature. Thus, if the door 202 is pushed or shaken, the anti-walk feature 136 can push the lock plate 116 in the direction of the open end 120 each time the peg 104 contacts the anti-walk feature. Movement of the lock plate 116 in the direction of the bias caused by the anti-walk feature 136 can prevent the peg (which is fixed to the door jamb 214) from leaving the open end 120 of the locking slot so that the peg stays engaged with the locking plate despite the pushing or shaking.
In the illustrated embodiment of
The body 102 can further comprise hanger eyes 138 extending from the flanges 110, 112 and/or lock plate 116. The hanger eyes 138 provide holes on each side of the door for attachment of extension handles (not shown) that hang down to an adult-accessible level when the lock mechanism 100 is used on tall doors.
Referring now to
In
If the peg 104 is positioned within the locking slot 118 (e.g.,
In
If the peg 104 is not positioned within the locking slot 118 (e.g.,
Referring now to
The locking mechanism 100 can move directly between the locked configuration and the interlocked configuration, and vice versa, by rotating the body 102 about the hinge axis to move the pin 104 into or out of, respectively, the interlock cut-out 130. However, the lock mechanism 100 cannot move directly between the interlocked configuration and unlocked configuration or vice versa. Rather, an intervening movement to the locked configuration is required to move the lock mechanism 100 from the interlocked configuration to the unlocked configuration.
Referring now to
It will be appreciated by those skilled in the art having the benefit of this disclosure that this door top sliding child safety lock provides increased reliability while retaining ease of installation and operation. It should be understood that the drawings and detailed description herein are to be regarded in an illustrative rather than a restrictive manner, and are not intended to be limiting to the particular forms and examples disclosed. On the contrary, included are any further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments apparent to those of ordinary skill in the art, without departing from the spirit and scope hereof, as defined by the following claims. Thus, it is intended that the following claims be interpreted to embrace all such further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments.
