Door lever lock

A child safety lock for a lever door handle is rotatably mounted on a first side of a door and is biased in a first position. The child safety lock has a holder adapted to engage the door handle so that rotating the door handle rotates the holder. A cover is pivotally mounted on the holder and is shaped to cover the holder. A lock assembly is disposed in a vicinity of the door handle. The lock assembly selectively engages the cover for preventing rotation of the cover.

FIELD OF THE INVENTION

The present invention is generally related to child safety door locks and, in particular, to a child safety lock for lever door handles.

BACKGROUND OF THE INVENTION

Known lever door handles or knobs operate by turning the handle on the door which removes a latch from a recess in the door jamb. While sometimes these lever handles have locks, the locks are frequently automatically unlocked when the door handle is rotated from the interior side of the door (i.e. inside of the building or room). Thus, the only way to prevent unlocking and opening of the door by a small child is to prevent turning of the door handle.

One such safety device, offered by G2 Products of Franklin, Wis., has a collar and clip that fit over a lever door handle located close to a door jamb. The collar has two arms that extend radially relative to the axis of rotation of the handle. When a child attempts to rotate the handle, the arms collide with the door jamb preventing rotation of the door handle. This design, however, does not work with French or double doors where no door jamb is positioned close to the door handle.

In addition, this type of safety lock will only provide entry from the opposite side of the door when opposing lever door handles on the same door operate independently. For door handles on the opposite sides of a door that must rotate simultaneously in order to open the door, this kind of safety lock will prevent entry from both sides of the door. With such a door handle arrangement, turning the lever handle from the outside of the door would also turn the lever handle on the inside of the door and, as a result, the lock would be broken if an individual forced the handle to turn so as to gain entry.

Furthermore, this type of lock must be manually reset every time an individual passes through the door. This may be problematic in that some individuals, such as visitors or older children, may forget to reset the lock.

Another known child safety door lock, offered by Safety 1stof Canton, Mass., includes a collar that is mounted to the door and fits around the axial shank of the lever door handle. This design has a spring loaded button that is placed along the circumference of the collar and biased outward from the collar and door surface. The button blocks the rotational pathway of the lever door handle so that the handle cannot be rotated unless the button is depressed and slid on the collar away from the handle. The device features an override, however, that permits the door handle to be turned, even when the lock is activated, if a turning force of over approximately five kilograms is applied. This level of force is believed to be greater than what a young child could provide and permits entry into the room from the opposite side of the door by adults and older children.

A disadvantage of this lock, however, is that the door handle mechanism must be disassembled to install the product. In addition, this type of lock also must be manually reset every time an individual passes through the door.

Another child safety door lock on the market is the LEVER LOK product offered by Mommy's Helper, Inc. of Witchita, Kans. This product features a bowl-shaped cover or shield that is mounted on the door and surrounds the sides and bottom of a door lever handle. As a result, the door lever handle may only be activated by reaching down through the open top of the cover. This prevents young children from accessing the door lever handle due to their limited reach. A disadvantage of this arrangement, however, is that the door latch plate must be disassembled for the product to be installed. In addition, the effectiveness of the product is limited by the height of the door lever handle.

Accordingly, it is an object of the present invention to provide a child safety lock for lever door handles.

It is another object of the present invention to provide a child safety lock that permits a door to be locked on one side while unlocked on the other side.

It is another object of the present invention to provide a child safety lock that automatically resets.

It is still another object of the present invention to provide a child safety lock for a door handle that may be installed without disassembling the door handle.

These and other objects and advantages will be apparent from the following specification.

SUMMARY OF THE INVENTION

The present invention is directed to a lever door handle child safety lock that locks the side of the door where a child is located while permitting adults to open the door from the opposite side.

More specifically, in accordance with the present invention, a child safety lock for a lever door handle is rotatably mounted on a first side of a door and is biased in a first position. The child safety lock has a holder adapted to engage the lever door handle so that rotating the door handle rotates the holder. A cover is pivotally mounted on the holder and is shaped to cover the holder. A lock assembly is disposed in a vicinity of the door handle. The lock assembly selectively engages the cover for preventing rotation of the cover.

The lock assembly includes a lock housing that is mounted above the cover. An activator including a latch and a button slides within the housing and is biased by a spring so that the latch engages an indent formed in the cover when the device is locked. The button extends through an opening in the front of the lock housing and is lifted up by a user to raise the latch out of the cover indent. As a result, the device is unlocked so that the cover and holder may be rotated to open the door.

The following detailed description of embodiments of the invention, taken in conjunction with the appended claims and accompanying drawings, provide a more complete understanding of the nature and scope of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown inFIGS. 1 and 2, a child safety lock, generally indicated at10, is mounted on a lever door handle12that itself is mounted on a first side14(FIG. 2) of a door16that also has an opposite, second side (not shown). It will be understood that the invention can be used for a door with a door handle on only one side of the door or a door with a second handle on the second side of the door. The handle on the second side can be a lever door handle, a round door knob or any other type of door handle. The invention also works whether or not the second door handle operates independently of the door handle12on the first side of the door as explained below.

As also illustrated inFIGS. 1 and 2, the lever door handle12has a shank18extending from the first side14of the door and an elongated lever member20extending from a distal end of the shank and generally parallel to the door.

Referring toFIG. 1, the child safety lock10has a lever holder24engaging, and substantially enclosing, the door handle12so that both the holder and the lever member may be rotated about an axis of rotation ‘A’. A cover26is shaped to cover the holder and is pivotally mounted on the holder24so that it pivots about axis ‘A’. As illustrated inFIG. 1, the handle12is biased in a first position, or counter-clockwise, so that the holder24remains covered by cover26. A lock assembly28is disposed in a vicinity of the door handle12where, as will be explained in greater detail below, it can engage the cover26in order to lock it in place.

As shown inFIGS. 3 and 4, the holder24has an elongated body or housing30cooperatively formed by an upper half32, that fits over a top of the lever member20, interlocking with a lower half34that fits over the bottom of the lever member20. A cushion pad36and38is made of a soft, compressible material, such as foam rubber, that will not scratch or damage the lever member20. The pads36,38are placed between sides of the lever member20and the interior surfaces40of the holder halves32,34. The pads36,38provide a snug fit for the lever member20within the assembled holder24in addition to preventing damage to the lever member.

As illustrated inFIGS. 3 and 4, the housing30has a generally cylindrically shaped first end composed of portions42aand42b, an opposing distal, second end composed of portions44aand44b, and sidewalls46a,46b,48aand48bformed by halves32,34. A lip70is provided on a top edge72of one of the halves to mate with a groove (not shown) on the sidewall of the opposite half in order to maintain alignment of the sidewalls46a,46b,48aand48b. The cylindrical end of the holder24has curvilinear extensions50a,50b,52aand52bextending laterally in opposite directions and outward from the sidewalls of the holder. Each end of an extension defines one of two opposing circular openings54,56.

The holder24also has a key-hole cover or cap58dimensioned to alternatively cover a selected one of the openings54,56. A rim64on the cap has a groove66engaging a circular edge68on cylindrical end42that defines either opening54,56. Thus, either of the openings54,56can receive the shank18of the door handle12while the other opening54or56can receive the cap58. With this configuration, the holder24is adaptable to alternatively fit on either a left-hand or a right-hand lever handle.

As shown inFIGS. 3 and 4, the upper half32of the housing30has a locking slot60at housing end44afor receiving a hooked locking tab62positioned on half34in order to secure the two halves32and34to each other. The other end42aof half32also has a locking slot (not shown) that receives tab63positioned on the end42bof half34.

It will be appreciated that although the holder24encloses the entire lever member20(i.e. none of the lever member20is visible from the exterior of the holder20) configurations that merely enclose a substantial portion, or even a small part, of the lever member20are still within the scope of the invention. Holder24, however, must engage the lever member20, rotate with the lever member and provide a way for cover26to attach to, and pivot relative to the holder24while preventing operable access to the lever member20.

As shown inFIGS. 4 and 5, the cover, indicated in general at26, has a top wall74, a curvilinear first end76, and a back wall78at a distal second end80. The first end76of the cover26is curvilinear to align with the curved surface of the cylindrical end of the holder and to avoid interference with lock assembly28(FIGS. 1 and 2) as it is rotated when the lock assembly is unlocked.

As illustrated inFIG. 4, the cover26also has generally triangular sidewalls82,84that are sized to cover at least a substantial portion of the exterior of the sidewalls of the holder24. The cover back wall78also covers the second or distal end of the holder24. In the illustrated embodiment, everything but the bottom and cylindrical end of the holder24is covered by cover26so that a child cannot extend his or her fingers between the holder24and the cover26when the cover is locked and the door handle is not being operated. With this configuration, it is impossible to grasp the holder24to rotate it. Only the cover26is accessible and it cannot be rotated, so as to rotate the holder24and open the door, unless it is unlocked.

Cover26has concave, circular edges86(FIGS. 4 and 2) and88(FIG. 2) positioned below the first end76of the cover26. The two edges86,88are spaced from and aligned with each other for respectively engaging, and rotating about, the extensions50a,50b,52aand52bof holder24.

The first end76of top wall74of the cover26features an indent90that, as will be explained below, is engaged by lock assembly28. The portion150of the top wall76forming the indent90is shallow so that it does not interfere with rotation of the holder24.

Referring toFIG. 5, the lock assembly28has a lock housing92with a base plate94that is mounted on a door above the door handle. The base plate94has holes152for receiving screws154shown inFIG. 2in phantom, but could be mounted to the door in any manner sufficient to hold the lock assembly28on the door, including other types of fasteners, adhesives, etc.

As illustrated inFIGS. 5 and 6, the lock housing92also has a front cover96with a top wall98, a bottom wall100, a front wall102and sidewalls104,106. The sidewalls104,106have slots108,110for receiving tabs112,114extending horizontally from edges of the base plate94to distal hooked-ends156and157to secure the front cover96to the base plate94. The tabs112,114are respectively positioned between interior walls116,117and sidewalls104,106to maintain the hooked ends of the tabs in slots108,110. It will be appreciated that while two tabs are shown, in the alternative more than two tabs may be used. Of course, many other ways of securing the front cover96to the base plate94without the use of tabs is also contemplated.

As illustrated inFIG. 5, a mounting plate118is placed between the base plate94and front cover96. The mounting plate118has two vertical inner guide walls120and121that slide within outer guide walls148and149extending from the front cover96(shown onFIGS. 1 and 5). A horizontal stopper wall122(FIG. 5) also extends from the mounting plate118forming a portion of the bottom wall of the housing92. As illustrated inFIG. 5, an activator124is positioned between the mounting plate118and the front cover96. The activator124is slidably positioned between the outer guide walls148and149and has a button126extending through an aperture128formed in the front wall102of the front cover96.

The activator124also has a downwardly extending, integrally formed latch130that extends through an aperture132formed in the bottom wall100of the housing92. The stopper wall122of the mounting plate is positioned below a portion of the activator124behind the bolt130. As a result, the stopper wall122prevents the activator from falling out of the bottom of the housing92.

The activator124also has a cut-out134defining a seat136with an upward extending mounting pin138(FIG. 1) which aligns with a mounting pin140(FIG. 1) extending downward from the top wall98of the housing92. A helical spring142has a lower end144engaging the seat136and mounted on the pin138, and an upper end146engaging the pin140. As illustrated inFIGS. 1 and 2, the spring biases the activator124downward and the bolt130out of the lock housing92through aperture132, where it engages indent90of the cover26.

In order to secure the locking assembly28above the cover26, as illustrated inFIG. 1, the base plate94(FIG. 5) is first mounted on the door. The user then moves the front cover96, within which the remaining components ofFIG. 5have been assembled, so that bolt130slides through indent90of the cover26until the front cover fully engages tabs112,114securing the front cover96to the base plate94. The indent90must be elongated to provide enough space for the bolt130to be received while the front cover96is vertically aligned with, and horizontally spaced from, the base plate94so that the tabs156,157of the base plate94may be inserted into the front cover96for engagement with tabs112,114.

As shown inFIG. 1, the locking assembly28defaults to a locked position where bolt130is biased downward and engages indent90, which prevents the cover26from being rotated, effectively preventing the opening of the door from the first side of the door. A child attempting to turn the handle from the first side of the door cannot move the holder24since it is covered by cover26, and must attempt to rotate the handle by applying force on the locked cover26.

As shown inFIG. 7, lifting the button126on the lock assembly28upward compresses spring142(FIGS. 1 and 2) and moves the activator124upward. This action disengages bolt130from indent90permitting the cover26, holder24and lever handle20to rotate clockwise when cover26is turned clockwise so that the door may be opened.

The door, however, can still be opened from the opposite or second side of the door even if the door handles on opposite sides of the door rotate together. As shown inFIG. 8, when a door knob or handle on the second side of the door is turned, the holder24is free to rotate clockwise and away from cover26since the lock assembly28only engages the cover26and not the holder24. As a result, the door may be opened from the opposite or second side even though it is locked on the first side.