GB1584777A

GB1584777A - Autolock mechanism in a storage cabinet

Info

Publication number: GB1584777A
Application number: GB32952/76A
Authority: GB
Original assignee: Vickers Ltd
Current assignee: Vickers Ltd
Priority date: 1977-10-18
Filing date: 1977-10-18
Publication date: 1981-02-18

Description

(54) AUTOLOCK MECHANISM IN A STORAGE CABINET (71) We, VICKERS LIMITED, a British Company of P.O. Box 177, Vickers House, Millbank Tower, Millbank, London, SWiP 4RA., do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following state ment - 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 so that more than one drawer cannot be opened at once thereby eliminating the risk of the cabinet toppling over about the front edge of its base under the action of heavily laden drawers.

According to the invention, there is provided, in 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 mechanism comprising an upright locking bar which is displaceable longitudinally of itself between upper and lower positions which are respectively a drawer-locking position and a drawerreleasing position, respective cam tracks on the drawers and operative to efect and control such upward and downward longitudinal displacement of the locking bar by acting on respective portions of the locking bar and a latch associated with each drawer and operative to engage with a respective part of the locking bar, the arrangement being such that during the initial part of opening any one of the drawers, the bar is moved longitudinally in one direction by one of said cam tracks and the latch associated with said drawer is caused to engage with its respective locking bar part to lock the remaining drawer(s) shut, and such that the closing of the said drawer releases the latch from its respective locking bar part and moves the locking bar to unlock the remaining drawer(s).

A particular advantage of this construction is that it enables springs to be completely eliminated from the mechanism thereby reducing manufacturing costs and increasing the reliability of the action of the mechanism.

The said portions of the locking bar that are acted on by the cam tracks may be actuating tags each also providing a said respective part of the locking bar to be engaged by the associated latch. Each cam track may be provided with a shoulder such that during the initial part of opening of the said one drawer, the or each actuating tag associated with the or each remaining drawer engages with the said shoulder of the cam track of that drawer to lock the same shut.

In a preferred construction, each latch includes a release tongue which is so arranged that on closing the said one drawer, a part of the cam track of that drawer strikes the said release tongue to release the latch from engagement with the associated actuating tag. A preferred arrangement is one in which an upright channel member is included in the storage cabinet and the locking bar is mounted in the channel of the channel member for longitudinal displacement, and in which each latch includes a body part and a tag connected to the body part by a neck part, the channel member being formed with a plurality of apertures, one for each latch, and each latch being mounted with an edge of its neck part bearing on a bottom edge or corner of the associated aperture to provide a knife-edge pivot for the latch, Conveniently, each aperture may then be sectorshaped with the V of the sector at the bottom and the width of the neck part of the associated latch is then substantially the same as the radial dimension of the said aperture. A radial slot preferably extends from one upper corner of each aperture to terminate at a distance from the bottom corner of the said aperture which corresponds to the width of the associated tag as taken parallel to the width of the neck part.

The arrangement of each said aperture and its radial slot may be such that the tag is never aligned with the said radial slot in any working position of the associated latch.

Expediently, each latch includes a lobe which is so arranged that any tendency to misalignment of the latch is resisted by the lobe coming into contact with an adjacent surface of the channel member. Each latch may conveniently consist of a sheet metal pressing.

In a further preferred arrangement, a key-lock mechanism, associated with the autolock mechanism, is provided in the storage cabinet, the key-lock mechanism being operatively coupled to the locking bar and being so constructed and arranged as to leave the bar free to be displaced between its drawer-locking and drawerreleasing positions when the key-lock mechanism is unlocked but to displace the bar into its drawer-locking position when the keylock mechanism is locked. The keylock mechanism may comprise a flag of generally inverted L-shape secured to the upper end of the locking bar, and a keyoperated lock incorporating a roller adapted to cooperate with the flag and being mounted eccentrically relative to an axis of the key-operated lock to be angularly displaceable about that axis between locking and unlocking positions.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a side view of a part of one form of autolock mechanism, in accordance with the invention, incorporated in a filing cabinet (not shown), Figure 2 is a sectional view along the line A-A of Figure 1, Figure 3 is a perspective view of a latch included in the autolock mechanism, Figures 4 and 5 are side views of the filing cabinet, illustrating diagrammatically operation of the autolock mechanism, these views being taken in the opposite direction to the view of Figure 1, Figure 6 is an exploded, perspective view of a key-lock mechanism asociated with the autolock mechanism, and Figure 7 illustrates the different working positions of a flag which is associated with the autolock mechanism.

Referring to Figures 1 to 5 and Figures 1 and 2 in particular, the filing cabinet (illustrated diagrammatically in Figures 4 and 5 only) comprises a number of drawers (for example two drawers) arranged one above the other, the top drawer being shown at 1 in Figure 2. It is to be understood that the following description of the drawer 1 and its associated components of the autolock mechanism applies equally to all the drawers.

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 betyeen 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. The tag for the drawer 1 is designated 5 and as can be seen it is bent outwardly at right angles to the locking bar to project through an aperture 6 in the base wall of the channel member 2.

The actuating tag 5 co-operates with a cam track 7, secured to the side wall of the drawer 1, in certain positions of the drawer as will be explained hereinbelow. 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 autolock mechanism additionally comprises a latch for each drawer, the latch associated with the drawer 1 being indicated at 8. Conveniently, the latch is formed from a pressing in sheet metal to provide a body part 80, a tail part 81, including a latching portion 82, a release tongue 83, a lobe 86, and a tag 84 connected to the body part by a neck part 85 (see Figure 3 in particular), the tongue 83 and tag 84 being bent at right angles to the plane of the body part.

In order to attach each latch to the channel member 2, a number of apertures (such as the aperture 9 for the latch 8) are formed in the base wall. The aperture 9 is sector-shaped with the V of the sector at the bottom as Figure 1 shows, and its radial dimension is substantially the same as the width of the neck part 85 of the latch 8. From one upper corner of the aperture a radial slot 10 extends so as to terminate at a distance from the bottom edge or corner 12 of the aperture 9 which corresponds to the width of the tag 84 taken in a direction parallel to the width of the neck part 85.

To assemble the latch 8 to the channel member 2, the tongue of the latch is slipped through the base wall of the channel member, using the aperture 9 and slot 10, until the neck part 85 is located within the thickness of the base wall, when the lower side edge of the neck part can be brought into contact with the corner 12 of the aperture 9. Because the width of the neck part is the same as the radial dimension of the aperture 9, the latch can now pivot about the bottom corner 12. It will be appreciated that the lower side edge of the neck part bearing on the bottom corner 12 constitutes a knife edge pivot for the latch.

The position of the latch ilustrated in Figure 1 is a latching position, in which the latching portion 82 of the tail part 81 is engaged under the actuating tag 5. The latch can pivot rearwardly into a released position indicated in outline at 11 in Figure 1, in which the lower edge of the release tongue 83 of the latch rests on the top surface of the cam track 7. The purpose of the lobe 86 is to ensure that the latch 8 remains correctly aligned in all positions of the latch, any tendency to misalignment being resisted by the lobe 86 coming into contact with the adjacent surface of the base wall of the channel member. It should be noted that even in the released position of the latch, the tag 84 is not brought into alignment with the slot 10 and so for all working positions the latch is held captive in the aperture 9 by the tag 84.

Operation of the autolock mechanism will now be described with particular reference to Figures 4 and 5. In Figure 4, both drawers of the filing cabinet are closed. It will be seen that both latches are in their released position with their release tongues resting on the cam tracks of the drawers, and that the actuating tags are positioned at the entrances to their cam tracks. As the top drawer is opened, relative movement between the inclined cam track 7 and the actuating tag 5 causes the locking bar 4 to slide vertically in the channel member.Just as the locking bar approaches its uppermost position, the rear edge 13 of the upper part of the cam track moves clear of the release tongue 83 so that, as the drawer 1 is further opened, the latch 8 pivots forwardly under gravity and its hook engages under the tag 5 to lock the locking bar in its uppermost 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 seen from Figure 5 that in this position the actuating tag associated with the lower drawer is situated opposite a shoulder 22 at the entrance to the cam track of this drawer. It will be noted that any attempt to open the bottom drawer of the filing cabinet will fail because the shoulder 22 abuts with the actuating tag 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 rear edge 13 of the cam track 7 strikes the release tongue 83 and pushes it rearwardly to release the hook of the latch from beneath the actuating tag 5, which then rests on the cam track. As the drawer is shut further, the locking bar is lowered by the actuating tag 5 following the downward path of the cam track 7. When the drawer 1 is fully shut, the bottom drawer can be opened if desired, since the actuating tag associated with it is no longer opposite the shoulder 22 but is in fact aligned with the entrance to its cam track. Clearly, the autolock mechanism functions in an analogous way, when the bottom drawer is opened, to lock the top drawer shut.

It is to be noted that the cam tracks have downwardly sloping portions (such as the portion 15 of the cam track 7) to ensure that even if the locking bar should drop at all while any drawer is fully open, the necessary engagement between the cam track and actuating tag to lower the locking bar can be guaranteed as the drawer is shut.

Referring to Figure 6, a key-lock mechanism comprises a flag 16 of bent strip metal having a generally inverted L-shape welded to the top end of the locking bar 4, and a roller 18 adapted to cooperate with the flag. The roller 18 is eccentrically mounted, relative to the axis of the barrel 19 of a key-operated lock 20, on an arm 21.

Operation of the key-lock mechanism will now be described with reference to Figures 6 and 7. The roller 18 is shown in its unlocked position in Figure 6 with all the drawers shut when, as shown in Figure 7, the roller 18 is positioned at the entrance to a channel 26 formed in the end portion of the bent strip metal constituting the flag.

If one of the drawers is opened, the resulting vertical displacement of the locking bar causes the flag 16 to move into the position 16' indicated in dotted lines in Figure 7 while the roller 18 remains stationary. On closing the drawer, the flag 16 returns to its original position with the roller 18 at the entrance to the channel 26.

When (with all the drawers shut) a key is inserted into the lock 20 and turned, the arm 21 rotates through a half revolution anticlockwise so that the roller 18 follows the arcuate path 23 to arrive at the locking position 18'. It will be appreciated from Figure 6 that as the roller 18 moves along the path 23 it initially enters the channel 26, then it moves right to the bottom of the channel and then returns to the position 18' at the entrance to the channel 26. During this time, the flag has been raised by the roller 18 from the position indicated in full lines to the position 16'. Thus, all the actuating tags on the locking bar are posi- tioned opposite their respective shoulders alongside the entrances to the cam tracks 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 any number of 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.

WHAT WE CLAIM IS:- 1. In 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 mechanism comprising an upright locking bar which is displaceable longitudinally of itself between upper and lower positions which are respectively a drawer-locking position and a drawer-releasing position, respective cam tracks on the drawers and operative to effect and control such upward and downward longitudinal displacement of the locking bar by acting on respective portions of the locking bar and a latch asociated with each drawer and operative to engage with a respective part of the locking bar, the arangement being such that during the initial part of opening any one of the drawers, the bar is moved longi tudinally in one direction by one of said cam tracks and the latch associated with the said drawer is caused to engage with its respective locking bar part to lock the re maining drawer(s) shut, and such that clos ing of the said drawer releases the latch from its respective locking bar part and moves the locking bar to unlock the re maining drawers).

2. An autolock mechanism according to Claim I, in which said latch is caused by gravity to engage with its respective locking bar part after the associated drawer has been opened by a predetermined amount.

3. An autolock mechanism according to Claim 1 or Claim 2, in which said portions of the locking bar that are acted on by the cam tracks are actuating tags also providing a said respective part of the locking bar to be engaged by the associated latch.

4. An autolock mechanism according to claim 3, wherein each cam track is provided with a shoulder such that during the initial part of opening the said one drawer, the or each actuating tag associated with the or each remaining drawer engages with the said shoulder of the cam track of that drawer to lock the same shut.

5. An autolock mechanism according to claim 3 or 4, wherein each latch includes a release tongue which is so aranged that on closing the said one drawer, a part of the cam track of that drawer strikes the said release tongue to release the latch from engagement with the associated actuating tag.

6. An autolock mechanism according to any one of claims 3 to 5, wherein an upright channel member is included in the storage cabinet and the locking bar is mounted in the channel of the channel member for longitudinal displacement and wherein each latch includes a body part and a tag connected to the body part by a neck part, the channel member being formed with a plurality of apertures, one for each latch, and each latch being mounted with an edge of its neck part bearing on a bottom edge or corner of the associated aperture to provide a knife-edge pivot for the latch.

7. An autolock mechanism according to claim 6, wherein each aperture is sectorshaped with the V of the sector at the bottom, and wherein the width of the neck part of the associated latch is substantially the same as the radial dimension of the said aperture.

8. An autolock mechanism according to claim 7, wherein a radial slot extends from one upper corner of each aperture to terminate at a distance from the bottom corner of the said aperture which corresponds to the width of the associated tag as taken parallel to the width of the neck part.

9. An autolock mechanism according to claim 8, wherein the arrangement of each aperture and its radial slot is such that the tag is never aligned with the said radial slot in any working position of the associated latch.

10. An autolock mechanism according to any one of claims 6 to 9, wherein each latch includes a lobe which is so arranged that any tendency to misalignment of the latch is resisted by the lobe coming into contact with an adjacent surface of the channel member.

11. An autolock mechanism according to any one of claims 3 to 10, wherein the latch consists of a sheet metal pressing.

12. An autolock mechanism according to any preceding claim, wherein a keylock mechanism, associated with the autolock mechanism, is provided in the storage cabinet, the key-lock mechanism being operatively coupled to the locking bar and being so constructed and arranged as to leave the bar free to be displaced between its drawer-locking and drawer-releasing positions when the key-lock mechanism is unlocked but to displace the bar into its drawer-locking position when the key-lock mechanism is locked.

13. An autolock mechanism according to claim 12, wherein the key-lock mech

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. 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 any number of 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. WHAT WE CLAIM IS:-

1. In 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 mechanism comprising an upright locking bar which is displaceable longitudinally of itself between upper and lower positions which are respectively a drawer-locking position and a drawer-releasing position, respective cam tracks on the drawers and operative to effect and control such upward and downward longitudinal displacement of the locking bar by acting on respective portions of the locking bar and a latch asociated with each drawer and operative to engage with a respective part of the locking bar, the arangement being such that during the initial part of opening any one of the drawers, the bar is moved longi tudinally in one direction by one of said cam tracks and the latch associated with the said drawer is caused to engage with its respective locking bar part to lock the re maining drawer(s) shut, and such that clos ing of the said drawer releases the latch from its respective locking bar part and moves the locking bar to unlock the re maining drawers).

13. An autolock mechanism according to claim 12, wherein the key-lock mech

anism comprises a flag of generally inverted L-shape secured to the upper end of the locking bar, and a key-operated lock incorporating a roller adapted to cooperate with the flag and being mounted eccentrically relative to an axis. of the key-operated lock to be angularly displaceable about that axis between locking and unlocking positions.

14. An autolock mechanism in a storage cabinet substantially as hereinbefore described with reference to Figures 1 to 7 of the accompanying drawings.