Patent Publication Number: US-2015082840-A1

Title: File cabinet drawer locking device

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a locking device for drawers of a file cabinet. 
     BACKGROUND OF THE INVENTION 
     Lower-priced file cabinets are commonly sold without a built-in lock. Some other cabinets may originally have a built-in lock, but the keys may be malfunctioning or the key may be lost. In these cases, a replacement lock provided by a locksmith may be expensive. It is desirable to have an inexpensive non-built-in locking device to lock a drawer of the file cabinet, in order to store and secure valuable, sensitive or confidential documents. 
     SUMMARY OF THE INVENTION 
     The present invention provides a locking system and a locking device for a file drawer of a standard file cabinet, and in particular a steel-constructed file cabinet. The locking system includes the locking device and a locking means. The locking device includes an elongated bar that includes a locking end and an opposed attaching end, and means for engaging a portion of file drawer frame that is fixed to the attaching end. The locking system of the invention is used with a file cabinet having a file drawer frame, wherein an upper portion of a file drawer frame includes an interior vertical wall that is engaged by the engagement means of the locking device. A locking means is then applied and secured to the locking end of the locking device that extends forward through an upper slot between the file drawer and the file drawer frame. The locking means prevents the locking device from being pulled through an upper slot formed when the file drawer is closed within the file drawer opening defined by the drawer frame, and prevents the file drawer from being pulled open. 
     In one aspect of the invention, the engagement means includes an upturned wall that extends perpendicularly from the elongated bar at the attaching end. The upturned wall has a laterally extending dimension that is at least as wide as, and typically wider than, the elongated bar, to provide a stable engagement with the interior vertical wall. The upturned wall has a height that covers at least a portion of the height of the interior vertical wall of the drawer frame, and typically extends to or beyond the upper edge of the interior vertical wall of the file drawer frame. 
     In another aspect of the invention, the upturned wall of the locking device has a forward-facing surface that faces the locking end. A fastener can be provided that is fixed or attached to the forward-facing surface of the upturned wall, for attachment to the interior vertical wall of the file drawer frame. The fastener is selected from the group consisting of a pressure-sensitive adhesive layer, a hook and loop mechanical fastener, and a magnetic fastener. 
     The locking device can optionally include a downturned wall extending perpendicularly from the attaching end and substantially parallel with the upturned wall, to prevent manipulating of the locking device through an upper slot of the drawer opening after the locking means has been applied and secured to the locking device. 
     The present invention also provides an engagement means that includes a hinge fixed to the attaching end of the elongated bar, and a hooking member extending from the hinge. The hooking member includes an extending member having a proximal end fixed to the hinge, and a distal end, and a return clasping member extending from the distal end of the extending member and extending toward the hinge. The return clasping member is spaced apart from the extending member by a gap having a dimension, wherein the gap accommodates the thickness of the vertically extending interior wall of a file cabinet when the return clasping member is hooked over the top edge of the interior vertical wall. 
     The present invention also provides an engagement means that includes a hooking member fixed to and extending perpendicularly from the attaching end. The hooking member includes an extending member having a proximal end fixed to the attaching end, and a distal end, and a return clasping member extending from the distal end of the extending member and extending toward the attaching end. The return clasping member is spaced apart from the extending member by a gap having a dimension, wherein the gap accommodates the thickness of the vertically extending interior wall of a file cabinet when the return clasping member is hooked over the top edge of the interior vertical wall. 
     In an aspect of the invention, the locking end can include a plurality of teeth along a side edge of the elongated bar. The locking means can comprise a ratcheting lock that engages ratchetingly the teeth to secure the locking means to the locking end of the locking device. The ratcheting lock ratchetingly and releasably engages the row of teeth along an edge of the elongated bar. A non-limiting example of a ratcheting lock is described in U.S. Pat. No. 4,617,810, the disclosure of which is incorporated by reference in its entirety. 
     In a further aspect of the invention, the locking end is typically configured to extend at least about 2 inches to about 2.5 inches (about 5 cm to about 6 cm), and up to about 3 inches to about 4 inches (about 8 cm to about 10 cm), from the upturned wall. The dimension is sufficient to minimize the length of the locking end of the elongated bar that will extend away from the front surface of the file cabinet drawer when secured. 
     In an aspect of the invention, the attaching end can include a transverse base portion extending laterally with and parallel to the plane as the elongated bar, wherein the upturned wall or the hinge extends from a rearward edge of the transverse base portion. The transverse base portion can extend from either or both side edges of the attaching end. 
     The present invention also provides a method for securing closed a file drawer within a drawer opening of a file cabinet, comprising the steps of: a) opening a file drawer of a file cabinet disposed within drawer opening defined by a file drawer frame; b) securing releasably the attaching end of a locking device described herein, to a vertically extending interior wall of an upper portion of the file drawer frame of the file cabinet; c) extending forward the locking end of the locking device through the drawer opening while closing the drawer, to expose the locking end through an upper slot between the file drawer and the file drawer frame; and d) attaching a locking means to the locking end to prevent the file drawer from opening within the drawer opening. 
     The present invention also provides an article of manufacture comprising: a) a locking device and optionally a lock and one or more keys; b) instructions for use by a consumer of the locking device with a file cabinet, for locking and securing a drawer of the file cabinet using the locking device; and c) a package for securing together the locking device, the optional lock and one or more keys, and the instructions. The instructions can direct the consumer to attach the locking device to the file cabinet, and for closing and locking the drawer in the file cabinet. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  shows a first embodiment of a locking device of the invention. 
         FIG. 2  shows a side elevation view of the locking device of  FIG. 1  to be installed into a file cabinet with the drawer in the open position. 
         FIG. 3  shows the locking device of  FIG. 2  installed into the file cabinet with the drawer in the closed position. 
         FIG. 4  shows a side elevation view of the locking device of  FIG. 3  with a ratcheting lock installed 
         FIG. 5  shows a top plan view of the locking device of  FIG. 4 , viewed along line  5 - 5 . 
         FIG. 6  shows a second embodiment of a locking device of the invention. 
         FIG. 7  shows the locking device of  FIG. 6  installed in a file cabinet, with the ratcheting lock installed, using a guard. 
         FIG. 8  shows the locking device of  FIG. 1  using an alternative two-member fastener to attach the locking device to the file cabinet. 
         FIG. 9  shows a third embodiment of a locking device of the invention that includes a hinge and a hooking member. 
         FIG. 10  shows the third embodiment of the locking device of  FIG. 9  with the hinge pivoted to an installed position. 
         FIG. 11  shows a top plan view of the locking device of  FIG. 9 . 
         FIG. 12  shows a side elevation view of the locking device of  FIG. 9  in the installed position attached to the file cabinet with the drawer in the open position. 
         FIG. 13  shows the locking device of  FIG. 12  installed into the file cabinet with the drawer in the closed position with the ratcheting lock installed. 
         FIG. 14  shows a fourth embodiment of a locking device of the invention that includes a hooking member. 
         FIG. 15  shows the locking device of  FIG. 14  installed into the file cabinet with the drawer in the closed position with the ratcheting lock installed. 
         FIG. 16  shows an article of manufacture including the locking device, a ratcheting lock, fastener elements, and instructions for use. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As used herein, the term “forward” refers to the front face of a file cabinet, and to a direction toward the front face of the file cabinet, while the term “rearward” refers to the rear of the file cabinet, and to a direction toward the rear of the file cabinet. 
     As used herein, the term “vertical” or “vertically”, refers to a direction between the top surface and the bottom of a standard file cabinet, while the term “horizontal” or “horizontally” refers to a direction generally parallel with a floor or other surface on which a standard file cabinet in placed. 
       FIG. 1  shows a first embodiment of a locking device  50  including an elongated planar bar  51  having an attaching end  52  and a locking end  53 . The attaching end  52  includes a transverse base  55  that extends from both side edges of the attaching end  52 , and at least one upturned wall  56 , illustrated as a pair of upturned walls  56   a  and  56   b  extending from the rearward edge  58  of the transverse base  55  on both sides of the bar  51 , and extending in a direction transverse to the long axis  98 , and perpendicular from the plane of the bar  51 . 
     The locking end  53  comprises a rounded edge for easier insertion into the slot  72  of a ratcheting lock  70 , described below. The bar  51  includes a plurality of lock engaging elements  54  (teeth or ridges) disposed along a portion of one side edge. The transverse slot  72  of the ratcheting lock  70  has a shape and size suitable to receive slidably the locking end  53  and the elongated bar  51  of the locking device, and a cylinder lock portion  74  having a keyway (not shown) to receive the blade of an operable key  78 . 
     In one aspect of the invention, the locking device  50  is useful in locking the drawer of a file cabinet shown in  FIGS. 2 through 5 . The file cabinet includes a top surface  100 , a front cabinet surface  102  having a file drawer frame  101 , and a file drawer  110  disposed and movable laterally within the file drawer frame  101 . The upper portion of file drawer frame  101  includes a horizontal wall  103  defining a portion of the drawer opening  104 , and an interior vertical wall  105  extending perpendicularly from an inner edge of the horizontal wall  103 .  FIG. 2  shows the file drawer  110  in the open position, allowing a user to install the locking device  50 . As shown in  FIG. 3 , after insertion into the opened file drawer  110 , the upturned walls  56   a  and  56   b  are placed flush against the interior vertical wall  105 , and the file drawer  110  is closed into the file drawer frame  101  with the locking end  53  of the elongated bar  51  extending through the upper slot  106  formed when the file drawer  110  is fully closed within the file drawer frame  101 . 
     To temporarily fix the locking device  50  to the interior vertical wall  105 , and prevent it from falling due to gravity, an attaching means  90  is secured to the forward-facing surface of the upturned walls  56   a  and  56   b,  and attached temporarily to the rearward-facing surface of interior vertical wall  105 , to temporarily hold the locking device  50  in place, without manual support or holding, while the file drawer  110  is being closed. The attaching means  90  can include an adhesive material having a pressure-sensitive adhesive, or a magnetic material. A suitable magnetic material is a neodymium magnet. 
     Optionally the attaching end  52  can include at least one downturned wall  57  extending perpendicularly from the plane of the bar  51  at the attaching end  52 . The upturned walls  56   a  and  56   b  and the downturned wall  57  provide a stop wall at the attaching end  52 , which extends both above and below the planar bar  51 . The upwardly extending wall(s) engages the interior vertical wall  105  of the file cabinet to anchor the locking device from being pulled through the drawer opening once the locking means has been applied to the device. The interior vertical wall  105  of a conventional file cabinet can be about 0.5-1 cm in height, such as 0.8 cm. Likewise, the downwardly extending wall prevents manipulating the locking device  50  through the upper gap  106  of the drawer opening once the locking means has been applied to the device. 
     One can appreciate that various configurations of an upwardly extending wall(s) can be employed that engage the interior vertical wall  105  to anchor the locking device from being pulled through the drawer opening once the locking means has been applied to the device. Likewise, various configurations of a downwardly extending wall can be employed that to prevent manipulating the locking device  50  through the drawer opening once the locking means has been applied to the device. 
     Once the locking device  50  is inserted into the drawer opening  104  and temporarily attached to the file drawer frame  101  using the attaching means  90 , the file drawer  110  is closed, and a locking means, illustrated as a ratcheting lock  70 , is installed over the rounded locking end  53  of the elongated bar  51  to engage ratchetingly the teeth  54  along the side edge of the bar  51 , thereby securing closed the drawer  110 . The ratcheting lock  70  can be disengaged from the teeth  54  by inserting and rotating the key  78  within the keyway of the cylinder lock portion  74 , thereby allowing the ratcheting lock  70  to be slid off and removed from the locking end  53 . 
     The width of the transverse base  55  of the locking device  50  is typically about 5 cm to about 12 cm, preferably from about 8 cm to about 10 cm. The upturned walls  56  and the downturned wall  57  are typically about 1 cm to about 2 cm in height. 
     Non-limiting examples of a material for the locking device include aluminum, hardened steel, tempered steel, chrome-plated steel, stainless steel, other metals and alloys, thermoplastic materials, including polycarbonate, acrylic, etc., and laminates and components thereof. 
       FIGS. 6 and 7  show an alternative embodiment of a locking device  60  including an elongated planar bar  61  having an attaching end  62  and a locking end  63 . A perpendicular wall  66  is fixed to the attaching end  62  proximate the transverse center and slightly below the vertical center of the wall  66 . An attaching means  90  can be fixed or attached to the inner surface of the wall  66 , just above the bar  61 . 
     Also illustrated in  FIGS. 6 and 7  is a planar barrier plate or guard  80  having a transverse slot  82  sized to accommodate the size and shape of the bar  61  of the locking device. The guard  80  can be made of a plastic or any of the materials used for constructing the locking device. The planar surfaces of the guard can also be coated with a plastic material to reduce chipping or scratching of the surfaces of the file cabinet. The guard  80  protects against the lock  70  from marring the outer surface of the file drawer  110  and file drawer frame  101 , as illustrated in  FIG. 7 . It is understood that a guard can be used with the first embodiment of the locking device shown in  FIG. 1 , or with any other embodiment herein. 
       FIG. 8  illustrates an alternative embodiment of the locking device wherein the attaching means is a hook and loop mechanical fastener. The fastener  92  is either the loop fastener member or the hook fastener member, which is typically attached adhesively to the forward-facing surface of the upturned walls  56   a  and  56   b.  The mating mechanical fastener  94  attached to the rearward-facing surface of the interior vertical wall  105  is the other of the loop fastener member or the hook fastener member, and is likewise typically attached adhesively. 
       FIGS. 9-13  illustrate a third embodiment of the locking device  150  that employs a hooking member to grasp the top edge of the interior vertical wall  105  to prevent its withdrawal. The locking device  150  includes an elongated bar  151  that includes a locking end  153  and an opposing attaching end  152 . A hinge  155  is secured to the attaching end  152  and to a hooking member  160  for pivoting movement of the hooking member  160  between an extended position shown in  FIG. 9 , and a hooked or installed position shown in  FIG. 10 . The hinge  155  can be any hinging member that allows the hooking member  160  to be moved or manipulated between the two positions. In the illustrated embodiment, shown in  FIG. 11 , the hinge  155  includes a plurality of circular loops  158  fixed to the distal edge of the attaching end  152  along an axis line  99 , and a plurality of corresponding circular loops  168  extending from the proximal edge of the extending member  162  of the hooking member  160 , and spaced between the loops  158 . The loops  158  and  168  are interlaced pivotally along the axis  99  with an elongated pin  170 .  FIGS. 9 and 10  show the extending member  162  extending from the hinge  155 , and the shorter clasping member  164  extending from the distal end  163  of the extending member  162  back toward the hinge, and spaced apart from the extending member  162  by a gap  169  having a dimension. The gap dimension is typically about 1 mm to about 2 mm. The gap accommodates insertion of the hooking member over a thickness of the upper edge of the interior vertical wall  105  of the file cabinet. Once hooked over the interior vertical wall  105 , as shown in  FIG. 12 , any downward force or torque upon the locking device  150  ensures that the hooking member  160  does not disengage during use. The user grasps the locking end  153  of the bar  151  and holds it along the upper horizontal wall  103  while closing the file drawer  110 , and locks the device with the locking means  70 . The clasping member  164  can extend any distance back toward the hinge  155  that is sufficient to easily clasp the interior vertical wall  105 , while remaining engaged with the top edge thereof. The confronting surfaces of the extending member  162  and the clasping member  164  do not need to grip the interior vertical wall  105 , although the gap  169  should not be so large that the device could tilt over and off of the interior vertical wall  105 . 
       FIGS. 14 and 15  illustrate a fourth embodiment of the locking device  250  that employs a hooking member to grasp the top edge of the interior vertical wall  105  to assist in installation of the locking device, and to help prevent its withdrawal. The locking device  250  includes an elongated bar  251  that includes a locking end  253  and an opposed attaching end  252 . A hooking member  260  includes an extending member  262  that extends from the attaching end  252 , and a shorter return clasping member  264  that extends from the distal end  263  of the extending member  262  back toward the attaching end  252 , and is spaced apart from the extending member by a gap  269  having a dimension, similar to that of the third embodiment. The attaching end  252  includes a transverse base  255  that extends from both side edges of the attaching end  252 . The extending member  262  extends from the rearward edge  258  of the transverse base  255  on both sides of the elongated bar  251 . 
     Once hooked over the interior vertical wall  105 , any downward force or torque upon the locking device  250  ensures that the hooking member  260  does not disengage from the vertical wall  105  during the initial placement of the locking device  250  to the file drawer frame. The user manipulates the locking end  253  of the bar  251  and holds it along the upper horizontal wall  103  while closing the file drawer  110 , and locks the device  250  with the locking means  70 . The return clasping member  264  can extend any distance back toward the attaching end  252  that is sufficient to easily clasp the interior vertical wall  105 , while remaining engaged with the top edge thereof and while providing a clearance to allow the forward-facing surface of the extending member  262  to fully contact the rearward-facing surface of the interior vertical wall  105 . The confronting surfaces of the extending member  262  and the clasping member  264  do not need to grip the interior vertical wall  105 , although the gap  269  should not be so large that the device could tilt over and off of the interior vertical wall  105 . 
     The invention also relates to instructions associated with the use of the locking device with a file cabinet, directing the consumer as to the manner and means to insert and attach the locking device to the file cabinet, and to close and lock closed the drawer in the file cabinet. The invention also relates to a method of closing and locking a drawer of a file cabinet using the locking device. Typically the method for securing closed a drawer within a drawer opening of a file cabinet comprises the steps of: a) opening a drawer of a file cabinet; b) attaching the attaching end portion of the locking device to the file drawer frame of the file cabinet; c) closing the drawer to expose the locking end portion; and d) attaching a locking means to the locking end to prevent the drawer from opening within the drawer opening. 
     As illustrated in  FIG. 16 , the invention also relates to an article of manufacture  140  comprising the locking device  50 , the locking means  70  and one or more keys  78 , and optional fasteners  90 , packaged in association with instructions  120  with a board  142  and clear overwrap  144 , for use by a consumer of the locking device with a file cabinet, and with a method of locking and securing a drawer of the file cabinet using the locking device.