GB2062082A

GB2062082A - Storage Cabinet

Info

Publication number: GB2062082A
Application number: GB7935101A
Authority: GB
Original assignee: Vickers Ltd
Current assignee: Vickers Ltd
Priority date: 1979-10-10
Filing date: 1979-10-10
Publication date: 1981-05-20
Also published as: BE881233A; GB2062082B

Abstract

In a storage cabinet comprising a plurality of drawers arranged one above the other, an autolock mechanism comprises a locking bar 4 to be raised by cam action during the initial opening of any drawer for locking the remaining drawers shut. Teeth on the bar turn a pinion 22 to carry spring 13 through an over- centre position between positions for holding the bar in its locking and unlocking positions. If the cabinet is tilted forward substantially a ball 42 inhibits rotation of pinion 22 and therefore movement of bar 4. <IMAGE>

Description

SPECIFICATION Storage Cabinet This invention relates to a storage cabinet having a plurality of drawers arranged one above the other, and more particularly to an autolock mechanism in such a cabinet, for locking the remaining drawer(s) shut when one of them is opened.

Storage cabinets are known, including drawers arranged one above the other, in which the drawers can be opened and closed independently of one another. A disadvantage is that more than one drawer can be opened at once and if the drawers are sufficiently laden, this can result in the cabinet toppling over about the front edge of its base. This presents a serious hazard to users of such storage cabinets.

In the present Applicants' earlier British Patent Application No. 28190/77, there is disclosed a storage cabinet having a plurality of drawers arranged one above the other, an autolock mechanism for locking the remaining drawer(s) shut when one of them is opened, the autolock mechanism comprising an upright locking bar which is displaceable longitudinally of itself between upper and lower positions, one of which is a drawer-locking position ad the other a drawer-releasing position, means associated with the drawers and operative to bring about locking bar displacement to lock the remaining drawer(s) shut during the initial part of opening one of the drawers and retaining mechanism, including a spring, operable by the locking bar and arranged so that when the locking bar is moved from the drawer-releasing position to the drawer-locking position the spring passes through an over-centre position from a first state in which it tends to hold the locking bar in the drawer-releasing position to a second state in which it retains the locking bar in the drawer-locking position, the retaining mechanism being arranged so that the spring returns to the first state when the locking bar is returned to the drawer-releasing position.

The aforesaid earlier invention may include a key-lock mechanism which is operatively coupled to the locking bar and which is so constructed and arranged to permit the bar to be raised and lowered when the key-lock mechanism is unlocked but to raise the bar to lock all the drawers shut when the key-lock mechanism is locked.

It has been found that when the drawers have not been locked shut by the key-lock mechanism and when, for example, the cabinet is being carried up or down stairs in a position in which it is turned from the upright position to a position in which the locking bar can slide under its own weight or inertia towards its locking position, all the drawers will be locked shut by this movement.

Then when the cabinet is returned to the upright position, the drawers will remain locked and cannot be unlocked by the lock because this will be held in the unlocked position by the locking bar in its raised position. It is therefore, an object of the present invention to provide simple means whereby this action can be avoided.

According to the invention, a storage cabinet comprises a plurality of drawers arranged one above the other, an autolock mechanism for locking the remaining drawer(s) shut when one of them is opened, the autolock mechanism comprising an upright locking bar which is displaceable longitudinally of itself between upper and lower positions one of which is a drawerlocking position and the other a drawer-releasing position, actuating means associated with each drawer operative to bring about locking bar displacement to lock the remaining drawer(s) shut during the initial part of opening the drawer, and retaining mechanism, including a spring operable by the locking bar and arranged so that when the locking bar is moved from the drawer-releasing position to the drawer-locking position it retains the locking bar in the drawer-locking position, and a gravity responsive device operative on the retaining mechanism to inhibit longitudinal movement of the locking bar if the cabinet is tilted in such a way as to cause the locking bar to travel to its drawer locking position, the gravity responsive device thereby preventing all the drawers from becoming locked by such movement of the locking bar. The gravity responsive device may conveniently comprise a ball arranged to run along a track to a position in which it obstructs the operation of toothed gearing which would otherwise transmit the movement of the locking bar to the spring, this obstruction occurring when the locking bar is moved towards the horizontal position.

In order that the invention may be clearly understood and readily carried into effect, one storage cabinet in accordance therewith will now be described, by way of example, with reference to the accompanying drawings, in which Figure 1 is a perspective view of part of a drawer autolock mechanism; Figure 1 A is an exploded perspective view showing details of a drawer key-lock device; Figure 1 B is a perspective view of part of a cabinet drawer, Figure 1C is an elevation of a detail of the mechanism shown in Figure 1; Figures 2 and 3 are respectively a front elevation and plan of part of the mechanism shown in Figure 1; Figures 4 and 5 illustrate diagrammatically the operation of the drawer autolock mechanism; Figure 6 illustrates different working positions of the details shown in Figure 1A; and Figures 7 and 8 respectively show different operative conditions of a portion of the mechanism shown in Figure 1.

Referring to Figures 1, 1 B and 3 to 5, filing cabinet (illustrated diagrammatically in Figures 4 and 5 only) comprises a number of drawers 1 (for example two drawers) arranged one above the other, the top drawer being shown in Figure 1. It is to be understood that the following description of the top drawer and its associated components of the autolock mechanism applies equally to all the drawers 1.

Arranged just inside the drawer opening in the front of the filing cabinet, on one side (e.g., the right-hand side) of the opening, is an upright channel member 2 which has outwardly directed side wing portions providing feet 3 on opposite sides of the channel by which the channel member is secured to the surface of the side wall of the filing cabinet.

Arranged within the channel of the channel member along one of its sides so as to lie between the base wall of the channel member and the facing wall of the filing cabinet is a locking bar 4 which is U-shaped in cross-section and can slide vertically within the channel member. One of the side walls of the locking bar is cut at locations spaced along its length to provide actuating tags 5 for the drawers, respectively. As can be seen in Figure 1, the tag 5 for the top drawer is bent outwardly at right angles to the locking bar 4 to project through an aperture in the base wall of the channel member 2.

Each actuating tag 5 cooperates with an associated cam track 7, secured to the side wall of the associated drawer 1, in certain positions of the drawer as will be explained hereinbelow, and for this purpose, the upper and lower faces of the tag are inclined downwardly at a small angle, typically 1 5 degrees, to the horizontal for good bearing contact with the cam track 7.

Conveniently, the cam track can be formed from a sheet metal blank which is bent to provide the required shape and then welded, for example, to the drawer side.

The locking bar 4 is formed along one edge with teeth 8 (Figure 2) engaged with the teeth of a pinion 22 which is rotatably mounted on the channel member 2 and which bears a radially projecting arm 33. Conveniently, the pinion and arm can be formed by a single sheet steel pressing. The free end of the arm 33 is bent over to form a tag 24 around which is fitted one end of a tension spring 1 3 whose other end is fitted around a tag 25 which is stamped from the base wall of the channel member and then bent out of the plane of the base wall.

When all the drawers of the filing cabinet are shut but not locked by a key-lock mechanism to be described hereinbelow, the bar 4 is in its lower position and the spring 13 is in the position illustrated in Figure 4. As the bar 4 is raised by the cam track 7 on opening one of the drawers, the bar rotates the pinion 22 anti-clockwise, and thereby cause the arm 33 to move from the full line position of Figure 2 so that the spring 13 goes beyond its over-centre position. As the drawer is opened further, the locking bar 4 arrives at its uppermost position, in which the spring 13 adopts the position shown in Figures 2 and 5.

Then the spring, still under tension, exerts by way of a substantial turning moment on the arm 33 a sufficient upward force on the locking bar to retain it in that position as the drawer is opened further.

Referring to Figures 1, 1 A and 6 a key-lock mechanism comprises a flag 16 welded to the top end of the locking bar 4, this flag being formed from a length of strip metal bent to the required shape. A roller 1 8 eccentrically mounted relative to a barrel 1 9 of a key-operated lock 20, on an arm 21, cooperates with the flag as will be explained in detail hereinbelow with reference to Figure 6.

Operation of the autolock mechanism will now be described in detail with particular reference to Figures 4 and 5. In Figure 4, both drawers 1 of the.

fIling cabinet are closed. It will be seen that the actuating tags 5 are positioned at the entrances to their cam tracks 7. As the top drawer is opened, relative movement between its inclined cam track 7 and actuating tag 5 causes the locking bar 4 to slide vertically in the channel member, thereby bringing the actuating tag 5 associated with the lower drawer into the position shown in Figure 5 where it is opposite a shoulder 9 at the entrance to the cam track. The spring 13 holds the locking bar 4 in its raised position even when the upper drawer 1 is opened fully and the actuating tag 5 is no longer urged upwardly by the cam track 7. It will be noted that any attempt to open the bottom drawer of the filing cabinet will fail because the shoulder 9 abuts with the actuating tag 5 associated with the lower drawer.

Thus, while the drawer 1 is open, the lower drawer is locked shut.

When the upper drawer 1 is pushed back towards its closed position, the cam track 7 comes into engagement with the actuating tag 5, a lower boundary 1 5 of the cam track ensuring that even if the locking bar should drop at all whilst the drawer is fully open, the necessary engagement between the cam track and actuating tag can be guaranteed as the drawer is shut. Owing to the engagement the cam track forcibly displaces the locking bar 4 downwardly and in so doing causes the tension in spring 1 3 to increase and to pass eventually through its centre state and finally return to the position shown in Figure 4. Then the bottom drawer can be opened, if desired, since the actuating tag 5 associated with it is no longer opposite the shoulder 9 but is in fact aligned with the entrance to its cam track 7. Clearly, the autolock mechanism functions in an analogous way, when the bottom drawer is opened, to lock the top drawer shut.

The key-lock mechanism will now be described with reference to Figures 1 and 6. The roller 1 8 is shown in its unlocked position in Figure 1. With all the drawers shut as shown by a broken line in Figure 6, the roller 1 8 is positioned at the entrance to a channel 23 formed in the flag. If one of the drawers is opened, the resulting vertical displacement of the locking bar causes the flag 1 6 to move into the position 1 6t indicated in full lines, while the roller 1 8 remains stationary. On closing the drawer, the flag 1 6 returns to its original position with the roller at the entrance to the channel 23.

When (with all the drawers shut) a key is inserted into the lock 20 and turned, the arm 21 rotates through a half revolution anti-clockwise so that the roller 1 8 follows the arcuate path 26 to arrive at the position 18'. It will be appreciated from Figure 6 that as the roller 1 8 moves along the path 26 it initially enters the channel 23, then it moves right to the bottom of the channel and then returns to a position 18' at the entrance to the channel 23. During this time, the flag has been raised by the roller 1 8 from the position indicated in broken lines to the position 16'. Thus, all the actuating tags on the locking bar are positioned opposite their respective shoulders 9 along side the entrances to the cam tracks 7 and so none of the drawers can be opened.To unlock the cabinet, it is merely necessary to rotate the arm. 21 through a half-revolution in the anticlockwise sense to lower the locking bar and thereby release the drawers.

Of course, although the description and drawings herein relate to a two-drawer cabinet, the autolock mechanism can be adapted to a filing cabinet with many more drawers merely by providing additional actuating tags on the locking bar and cam tracks on the additional drawers.

Then, opening of any one drawer will cause all the others to be locked shut.

In addition to the described autolock mechanism having a positive over-centre locking action, it is simple and cheap to produce in mass production, in particular because the pinion and its arm, and also the locking bar formed with its teeth, can be made in a sheet metal stamping process. In the case of the locking bar, the stamping process is followed by an appropriate bending operation.

It will be appreciated that when, for example, the cabinet is being carried up or down stairs in a position in which it is turned from the upright position to a position in which the locking bar 4, in the absence of some restraining device, can slide under its own weight or inertia towards what is normally the top end of the cabinet, all the drawers will be locked shut by this movement, it being assumed that the drawers have not previously been locked by the lock 20. Then when the cabinet is returned to the upright position, the drawers will remain locked and cannot be unlocked by the lock 20 because this will be held in the unlocked position by the locking bar 4 in its raised position.

A gravity actuated device is, therefore, mounted adjacent the pinion 22 for holding the locking bar down in such conditions. This gravity actuated device comprises a plastics member 40 fixed to the channel member 2 and formed with a bush 41 for the pinion 22. When the channel member 2 is upright a metal ball 42 lies at the bottom of a recess 43 in the member 40, the ball then being in the position A in Figures 7 and 8.

The recess 43 lies between a depression 44 formed in the channel member and a depression 45 in the member 40. Depending on whether the channel member 2 happens to be at the top of the tilted cabinet (Figure 7) or at the bottom of the tilted cabinet (Figure 8), when the cabinet is turned over to the horizontal or nearly horizontal position, the ball 42 will run along one or other of the sides 46, 47 (Figure 1 C) of the recess 43 into one of the depressions 44, 45 to take up the position B or C. When in a depression 44 or 45, the ball locks the pinion against rotation because the ball projects slightly out of the depression to engage a pinion tooth 48 so that the ball is held between the tooth and one side of the depression.

The locking bar 4 is, therefore, held against longitudinal movement so that the actuating tags 5 cannot engage the shoulders 9.

The inclination of the sides 46, 47 of the recess 43 is such that the ball 42 reaches its locking position before the locking bar 4 reaches the horizontal position.

Claims

1. A storage cabinet comprising a plurality of drawers arranged one above the other, an autolock mechanism for locking the remaining drawer(s) shut when one of them is opened, the autolock mechanism comprising an upright locking bar which is displaceable longitudinally of itself between upper and lower positions one of which is a drawer-locking position and the other a drawerreleasing position, actuating means associated with each drawer operative to bring about locking bar displacement to lock the remaining drawer(s) shut during the initial part of opening the drawer, and retaining mechanism, including a spring operable by the locking bar and arranged so that when the locking bar is moved from the drawer-releasing position to the drawerlocking position it retains the locking bar in the drawer-locking position, and a gravity responsive device operative on the retaining mechanism is inhibit longitudinal movement of the locking bar if the cabinet is tilted in such a way as to cause the locking bar to travel to its drawer locking position, the gravity responsive device thereby preventing all the drawers from becoming locked by such movement of the locking bar.

2. A storage cabinet according to Claim 1, in which the retaining mechanism comprises toothed gearing arranged so that when the locking bar is moved from the drawer-releasing position to the drawer-locking position the toothed gearing is actuated to cause the spring to pass through an over-centre position from a first state in which it tends to hold the locking-bar in the drawer-releasing position to a second state in which it retains the locking bar in the drawerlocking position, the gravity responsive device comprising a member free to move under gravity to a position such that it engages the toothed gearing and holds the locking bar against movement when the cabinet is moved from its upright position to a horizontal position, and free to move away from the holding position to an idle position when the cabinet is returned to the upright position.

3. A storage cabinet according to Claim 2, in which the freely movable member is a ball free to run under gravity along a track leading between the holding position and the idle position, the track being fixed with respect to the cabinet.

4. A storage cabinet according to Claim 3, in which the toothed gearing comprises a pinion in mesh with compiementary teeth on the locking bar, the spring being attached to an arm on the pinion and the track being so located that the ball engages a tooth on the pinion to inhibit its rotation when the cabinet is moved towards the horizontal position. ~~~~~~~~~~~~~~~~

5. A storage cabinet according to Claim 3 or Claim 4, in which depressions are formed on opposite sides of the toothed gearing, in one of which the ball is received when the cabinet is tilted with the autolock mechanism at the top of the cabinet and in the other of which the ball is received when the cabinet is tilted with the autolock mechanism at the bottom of the cabinet, and from either of which the ball will project into engagement with the gearing to hold the locking bar against movement.

6. A storage cabinet substantially as hereinbefore described with reference to the accompanying drawings.