US 3883200 A
A file drawer lock to automatically lock other drawers when one is opened, including a vertical locking bar spanning a plurality of file drawers mounted for reciprocal movement, latch levers mounted thereon for each drawer, and cam means cooperating between the vertical locking bar and drawers to actuate the latch levers for locking and unlocking of other drawers when one is opened.
Description (OCR text may contain errors)
United States Patent 11 1 Latham i May 13, 1975 1 1 FILE DRAWER LOCK  Inventor: Ernest W. Latham, North Aurora,
 Assignee: Bentson Industries Inc., Aurora, 111.
 Filed: Dec. 12, 1973  Appl. No.: 424,003
[52} US. Cl. 312/216; 312/221; 312/319  Int. Cl. E051) 65/46  Field of Search 312/216-219, 312/221, 222, 322, 323, 319
 References Cited UNITED STATES PATENTS 2,842,419 7/1958 Howard 312/222 2386392 5/1959 Stegmaier 312/217 3.378.321 4/1968 Frederick et a1. 312/319 3,404,929 10/1968 Wright et a1 312/216 FOREIGN PATENTS OR APPLICATIONS 6,291 3/1908 United Kingdom 312/221 Primary Examiner-Casmir A. Nunberg Attorney, Agent, or FirmErnest S. Kettelson  ABSTRACT A file drawer lock to automatically lock other drawers when one is opened, including a vertical locking bar spanning a plurality of file drawers mounted for reciprocal movement, latch levers mounted thereon for each drawer, and cam means cooperating between the vertical locking bar and drawers to actuate the latch levers for locking and unlocking of other drawers when one is opened.
5 Claims, 10 Drawing Figures PMENIEU MAY 1 3i975 SHEET 1 BF 2 PATENIED RAY I 31975 SHEU 2 BF 2 3 WWW I my vii A. I I I f IE I I i F IG.5
FILE DRAWER LOCK BACKGROUND OF THE INVENTION This invention relates to a mechanism for automatically locking other drawers in a file cabinet when one is opened.
Lateral file drawer cabinets have become increasingly popular in recent years for various reasons, including less space required to open drawers for access to files. However lateral files have a greater tendency to tip when drawers are opened than conventional file cabinets with drawers which open and close longitudinally. Thus it is desirable to provide a locking mechanism that automatically locks all other drawers and keeps them closed when one drawer is opened.
A number of attempts have been made to solve this problem but most have so far involved complicated ap paratus which is expensive, parts wear out quickly, the mechanism breaks down and all drawers might be locked accidentally so none can be opened.
It is therefore an object of this invention to provide a sturdy locking mechanism spanning a plurality of drawers, of simple design for trouble free operation throughout the entire useful life of the file cabinet, comprising a vertical locking bar spanning a plurality of drawers. latch means operable thereon to lock each drawer, and cam means associated with said drawers and said vertical locking bar to lock and unlock a plurality of drawers selectively.
It is an object of this invention to provide a file drawer lock for multiple drawers which automatically locks all other drawers in closed position when one is opened and keeps them locked until the opened drawer is closed whereupon they are automatically unlocked.
It is an object of this invention to provide a file drawer lock for automatically locking a plurality of drawers when one is opened which also serves the combined function of a security lock for all drawers.
SUMMARY OF THE INVENTION A vertical locking bar is provided which spans a plurality of file drawers in a vertical tier. Latch levers are mounted vertically in spaced apart relation along said vertical locking bar, hinged to the file cabinet wall or other fixed member to raise the vertical locking bar against gravity. Each latch lever is positioned so it may co-act with a receiving element on a respective drawer to lock it in closed position. Cam means are provided to co-act between the vertical locking bar and each drawer, to move and hold the latch levers in locking position when one drawer is opened. When such drawer is closed, the locking bar moves by gravity to an unlocked position releasing the latches from engagement with each drawer so any one of them may be opened.
The same mechanism may be used as a security lock for all drawers. A key lock of any conventional design may be coupled to a lever to raise the vertical locking bar, causing all latch levers to engage theri respective drawers in locked engagement when the key lock is moved into locking position. When the key lock is moved to unlocking position, the vertical locking bar moves downward by gravity causing the latch levers to release their respective drawers.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a file cabinet, partially broken away, incorporating the invention.
FIG. 2 is an enlargement of a broken away portion shown in FIG. 1.
FIG. 3 is a side elevation of the cabinet in FIG. I with the side wall removed to show the interior.
FIG. 4 is a side elevation of the front part ofthe cabi net shown in FIG. 3 illustrating the position of the lock ing mechanism when one of the drawers is opened.
FIG. 5 is a section taken on line 5 5 of FIG. 4.
FIG. 6 is a section taken on line 66 of FIG. 3.
FIG. 7 is a perspective view ofa portion of the upper interior of the cabinet of FIG. 1 showing the security lock mechanism incorporated as part of this invention.
FIG. 8 is a side elevation of the front upper part of the cabinet in FIG. 1 with the side wall removed and showing the upper drawer to be a shelf drawer.
FIG. 9 is the side elevation of FIG. 8 showing all of the drawers closed and the mechanism in unlocked position.
FIG. I0 is a section taken on line 10 10 of FIG. 9.
DESCRIPTION OF PREFERRED EMBOODIMENTS The drawings illustrate a preferred mechanism embodying this invention. A vertical locking bar I is mounted for limited reciprocal movement along the inner wall of a file cabinet 2 near the front thereof, spanning a plurality of drawers 3 in said cabinet.
Positioned adjacent each drawer along said vertical locking bar I are latch levers 4, whose fulcrums 5 are hinged to a fixed member 6 and at hinge points 7 to the vertical locking bar I, lever 4 being pivotal on hinge point 7 with respect to guide bar 1.
One of the latch levers 4 is shown in detail in FIG. 2. The other latch levers include identical elements and parts. A projecting roller 8 is journalled on pin 9 to the latch lever 4, forward of fulcrum hinge 5 or to the left thereof as shown in FIG. 2. A hook I0 is formed on the free end of latch lever 4 as shown to the left in FIG. 2.
Each drawer 3 includes a recess 1] in the inner face of front wall 12, aligned to received the hook 10 of a corresponding latch lever. The bottom edge I3 of recess 11 forms a lip to engage and bear against hook 10 when the drawer is closed and latch lever 4 is moved to a substantially horizontal position, thus retaining drawer 3, and locking it in closed position.
Along the side of each drawer 3 is a projecting rib 14 which extends longitudinally the length of the drawer and projects somewhat beyond the rear of the drawer. Nearthe front of the drawer the projecting rib l4 joins a cam surface 15 sloping upward from projecting rib 14.
The rollers 8 on latch levers 4 are positioned to cooperate with cam surface 15 when drawer 3 is opened by being pulled outward. Cam surface 15 forces roller 8 downward as the drawer is moved outwardly until engagement with projecting rib 14 which holds roller 8 depressed until drawer 3 is moved inwardly to closed position thereby disengaging rib l4 and cam I5 from roller 8. The weight of vertical locking bar I to which latch levers 4 are hinged causes locking bar I and hinge point 7 to move downward by gravity thereby raising the opposite end of latch levers 4 carrying rollers 8 and latch hooks 10. When a roller 8 on a latch lever 4 is depressed by engagement with cam 15 and rib l4 as one drawer 3 is moved outwardly, hinge point 7 and vertical locking bar 1 are lifted upwardly causing hinge points 7 of the other latch levers to move upwardly and the opposite ends of latch levers 4 which form books 10 move downwardly to enter recesses 11 in corresponding drawers and bear against lips 13 therein to hold said drawers locked in closed position until the one opened drawer 3 is moved to closed position releasing roller 8 of its corresponding latch lever 4 allowing vertical lock bar 1 to drop downward which simultaneously releases the other latch levers 4 and unlocks the other drawers of the cabinet 2.
Vertical locking bar 1 is mounted along the inside of a side wall 16 of cabinet 2. near the front wall 17. It is mounted for reciprocal movement vertically by hinged attachment to latch levers 4 at hinge points 7. The ful crums 5 of latch levers 4 are hingedly attached to fixed member 6 which extends vertically from the top to bottom of cabinet 2 along the inside of side wall 16 near front wall 17. Fixed member 6 is preferably spaced apart inwardly from side wall 16 a small distance to provide clearance for vertical locking bar 1 between the portion of latch levers 4 to which it is attached and side wall 16. Projecting rollers 8 are mounted on the inward facing side of latch levers 4, aligned for engagement with cam surfaces projecting from the side walls of corresponding drawers 3 and for continuous engagement with projecting rib 14 of a drawer 3 when moved outwardly to an open position.
A vertical locking bar 1 with cooperating latch levers 4 may be mounted on both sides of a cabinet 2 with corresponding elements as described to lock both sides of drawers 3 in closed position when one of said drawers is opened.
The drawers 3 may be mounted within the cabinet 2 for opening and closing on carriage and track of conventional design. The projecting ribs 14 and cam surfaces 15 in accordance with this invention may be easily mounted along the side of drawers without interfering with carriage and track on which the drawers slide for opening and closing.
The projecting ribs 14 extend longitudinally beyond the rear wall 18 of drawers 3 to form extending ledge 1411. When drawer 3 is fully withdrawn to the completely open position so rear wall 18 of drawer 3 is sub stantially in the same vertical plane as front wall 17 of cabinet 2, extending ledge 14a projects inwardly of cabinet 2 to continue depression of rollers 8 oflatch levers 4 thereby maintaining vertical lock bar 1 in raised position to lock the other drawers in closed position in the manner described.
The selective locking mechanism as described for selectively locking all other drawers in a cabinet when one is opened may also be utilized as a security lock in accordance with this invention. Vertical locking bar 1 is provided with a flange 19 at the top. A conventional spring loaded lever mechanism 20, biased toward a disengaged or unlocking position. is mounted to engage flange l9 and raise the vertical locking bar l upward when push lock 21. to which lever mechanism 20 is connected. is pushed inward to locking position. When vertical locking bar 1 is held in such raised position. the hooks [0 of latch bars 4 are lowered to engage the lips 13 of recesses ll of drawers 3 to hold them locked in closed position. The drawers remain locked until a key is inserted in push lock 21 and turned to unlock. where upon the spring loaded lever mechanism 20 is drawn to its disengaged position permitting vertical lock bar 1 to drop. raising lever latches 4 and thereby unlocking drawers 3. Push lock 21 is urged outwardly to unlock- 4 ing position by the spring loading of lever mechanism 20 to which it is connected.
The locking mechanism in accordance with this invention may also be utilized for filing systems which in clude one or more shelf drawers 3a in combintation with drawers having integrally fixed front walls 12. A shelf drawer 3a is one which slides in and out of a cabinet, but a lift door may be raised to permit access thereto without necessarily sliding the shelf drawer out. Since it is not integrally connected to a fixed front wall 12 as other drawers are for locking in the manner described, a lug 22 is provided on the inward facing side of vertical locking bar 1 in position to cooperate with flange 23 mounted on the side wall of shelf drawer 3a. Lug 22 alternately blocks and clears flange 23 as vertical locking bar 1 is raised and lowered to locking and unlocking position. When lug 22 blocks flange 23, shelf drawer 3a is restrained from moving outward and is held in its fully inward position. Such locking of shelf drawer 30 occurs automatically when one of the other drawers 3 of cabinet 2 is opened causing its corresponding latch lever 4 to be depressed upon engage ment with cam surface 15 and projecting rib 14 thereby raising vertical locking bar 1 to locking position with respect to other drawers as described.
The lift door 12a fronting shelf drawer 3a may include a locking recess 1] to receive a corresponding hooked end 10 of a latch lever 4 as described with respect to other drawers. so lift door 12a can be held in closed position by this means and shelf drawer 3a by means of the lug 22 cooperating with flange 23 when vertical locking bar 1 is raised to locking position. When vertical locking bar 1 is lowered to unlocking position, as when all drawers are closed allowing rollers 8 to ride along cam surfaces 15 permitting hook ends 10 oflatch levers 4 to move upwardly and the opposite ends at pivotal hinge points 7 to move downwardly, the door 12a is then released and may be opened to move shelf drawer 3a outwardly.
It is self evident that lugs 22 and cooperating flanges 23 may be provided on each side of a shelf drawer 3a to lock each side thereof in the manner described.
The vertical locking bar 1 in this invention may be sufficiently weighted to automatically lower itself by gravity to the unlocking position when upward force is released A separate mechanism is not needed to move vertical locking bar 1 to the unlocking position. The invention contemplates raising the vertical locking bar by leverage, whether by the latch levers 4 or the lever mechansim 20 of the security lock. Such levers can be de signed and dimensioned to provide whatever mechanical advantage desired to easily lift a vertical locking bar I of any appropriate weight calculated to automatically return it to unlocking position by gravitational force upon release of the upward force exerted through said levers.
The projecting rollers 8 on latch levers 4, which provide rolling friction as opposed to sliding friction. and the inclined slope of cam surfaces 15, further combine to minimize and reduce the manual force required to pull the drawers 3 outward which raises vertical locking bar 1 to locking position as described.
The weight of vertical locking bar 1 as exerted through latch levers 4 and projecting rollers 8 against cam surfaces 15 of drawers 3 when closed, also pro vides the advantage of biasing the drawers 3 against accidental or unintended outward movement until a positive force is exerted to cause one of such drawers to open.
Operation of the invention is as follows. When one drawer 3 in a tier of associated drawers is moved out' wardly. cam surface 15 projecting from the side of that drawer engages projecting roller 8 on the latch lever 4 which is mounted for cooperation with such drawer. As the drawer is moved outwardly, roller 8 is depressed by cam surface 15 until it is engaged by projecting rib 14 which holds roller 8 depressed while the drawer is open and until it is closed. When roller 8 is depressed, the end of latch lever 4 on which it is mounted is moved downward thereby raising the opposite end of latch lever 4 which is connected to vertical locking bar 1. The corresponding latch levers 4 similarly mounted with respect to the other associated drawers likewise move upward at the end connected to vertical locking bar 1 and downward at the opposite end on which hook 10 is formed. The hook 10 of each latch lever facing each drawer 3 which remains closed. enters recess 11 in the inner face of front wall 12 of each drawer and latches against the lower edge 13 of said recess thereby locking each of the other associated drawers closed when one of such drawers is opened. Such other drawers remain locked until the opened drawer is closed, whereupon roller 8 disengages from projecting rib l4 and rides upward along the slope of cam surface 15 until the opened drawer 3 is fully closed. The weight of vertical locking bar 1 connected to the opposite end of latch lever 4 moves that end down and the opposite end of latch lever 4 up as roller 8 becomes disengaged from projecting rib l4 and cam surface 15. All latch levers 4 connected to vertical lock bar 1 move in like manner drawer 3 is fully closed, thereby disengaging hooks 10 on the latch levers from recesses 11 and unlocking all associated drawers.
The invention described herein may be utilized in any file cabinet having a plurality of two or more drawers, either for lateral filing or for traditional longitudinal filing, in desks having one or more pedestals of drawers, and in any fixture having a plurality of associated drawers. The invention is most commonly used for vertical tiers of drawers simply because most cabinets having a plurality of drawers are arranged in that manner. However. the invention may be readily adapted for use with a horizontal tier of drawers by providing the elements described along one or both sides of each drawer and interconnecting a lateral bar across the top of the horizontal drawers to the vertical locking bars extending alongside of each drawer whereby the selective locking of the other drawers is accomplished when one of the drawers in the horizontal tier is opened. In like manner, the invention may be adapted for use in cabinets having both vertical and horizontal tiers of drawers. The lever age feature of this invention, which uses latch levers to raise the vertical locking bar 1 and operate the elements connected thereto, can provide the mechanical advantage needed or desired to easily lift and operate a plurality of co acting vertical locking bars and connected elements which would be required for a horizontal tier of drawers or cabinets having both vertical and horizontal tiers of associated drawers.
The particular forms of the invention described herein and illustrated in the accompanying drawings are preferred embodiments, and various changes in the size. shape. materials and arrangement of parts may be made without departing from the spirit ofthe invention or the scope of the attached claims.
Having thus set forth my invention, what I claim is:
l. A lock mechanism for a plurality of associated drawers, including selective restraining means operable to hold other 05 said drawers in pre-selected alignment upon movement of one of said drawers out of alignment, guide means operable throughout the path of movement of each of said drawers. follower means cooperating with said guide means. connecting means between said follower means and said selective restraining means. said connecting means including a gravity biased locking bar connecting said follower means and said selective restraining means and being mounted for reciprocal movement between a locking position and an unlocking position, a weight incorporated in said connecting means adapted to adequately bias said connecting means toward one of said positions, and lever means operably mounted between said drawers and said weighted connecting means, said lever means providing a selected mechanical advantage proportional to the weight provided for said connecting means to enable convenient movement of said drawers.
2. A lock mechanism for a plurality of associated drawers, including a latch lever having a latch end and a lift end associated with each drawer. a latch catch mounted for latching cooperation with each of said latch levers. a projecting cam and a projecting rib mounted to form a continuous guide along each drawer, a following roller element rotatably mounted near the latch end of each of said latch levers for guidable engagement with a corresponding said projecting cam and projecting rib, and a gravity biased locking bar inter-connecting the lift ends ofsaid latch levers associated with each drawer. said locking bar being mounted for reciprocal movement between a locking position and an unlocking position, said locking bar being raised to locking position upon movement of a drawer out of said pre-selected alignment whereby said projecting cam and rib engage said corresponding following roller element and depress the latch end of said latch levers, said locking bar being lowered to unlocking position by virute of its gravitational bias upon disengagement of said following roller element from said projecting rib and cam when said drawer is moved back into said preselected alignment.
3. A lock mechanism for a plurality of associated drawers as set forth in claim 2, including a projecting lug mounted on said locking bar adjacent one of said drawers. and an abutting flange mounted on said drawer to butt against said projecting lug when said locking bar is in locking position.
4. A lock mechanism for a plurality of associated drawers set forth in claim 3, including a security key lock mounted for association with said locking bar, and lever means operably connected between said key lock and said locking bar for moving said locking bar and associated latch lever into locking position with respect to all of said associated drawers.
5. A lock mechanism for a plurality of associated drawers as set forth in claim 3, wherein said locking bar, latch levers, latch catches and projecting cams and ribs are operably mounted along one side ofsaid associated drawers, and mirror images of said locking bar, latch levers, latch catches and projecting cams and ribs are operably mounted along the opposite side of said associated drawers.