GB2259942A

GB2259942A - Catch mechanism; drawer interlock

Info

Publication number: GB2259942A
Application number: GB9219941A
Authority: GB
Inventors: David Seagrove Atkins
Original assignee: WIJK ARNOLDUS ADRIAAN
Current assignee: WIJK ARNOLDUS ADRIAAN
Priority date: 1991-09-25
Filing date: 1992-09-21
Publication date: 1993-03-31
Anticipated expiration: 2012-09-21
Also published as: ZA917646B; GB2259942B; IT1258490B; FR2681518A1; ITRM920692A1; CA2078257A1; GB9219941D0; DE4231946A1; ITRM920692A0

Abstract

A catch and a locking system for a cabinet with a plurality of drawers (10) which includes a number of catch mechanisms (25) each of which is associated with a respective drawer. Each catch mechanism has a retaining member (28), a biasing member (30) and a spring (48) which acts on the biasing member. All the retaining members are mounted on a shaft (39) which is biased by a second spring (61). When the drawers are closed cams (18) on the drawers act against the biasing members (30) and the retaining members (28) are urged to inoperative positions by the second spring (61) so that any drawer can be opened. If one drawer is opened the associated biasing member (30) is freed from the cam (18) and urges the retaining member (28) and all the remaining retaining members (28) to operative positions at which the remaining retaining members (28) engage behind the respective cams (16) and so prevent the remaining drawers (10) from being opened. <IMAGE>

Description

v Catch Mechanism This invention relates generally to a catch mechanism

and more particularly to a catch mechanism suitable for use with a cabinet of the kind described in the applicant's South African patent No.89/1875. (European patent application No.89307466.6).

The specification of the aforementioned patent primarily relates to a cabinet which includes a frame, at least one drawer wnich is movable into or out of the frame between closed and opened positions, and a catch mechanism which includes a first member adapted to be secured to the drawer, a shaft which is rotatably mounted to the frame, a catch which is fixed to, and which is rotatable with, the shaft, the catch being movable between a first position at which it engages with a locking formation on the first member when the drawer is closed thereby to, prevent the drawer from being opened and a second position at. the catch is disengaged from the first member, and biasing means which acts on the catch when the drawer is opened, thereby causing movement of the catch to the first position.

It is an object of the present invention to provide a catch mechanism of simplified construction and ease of operation.

2 The invention provides a catch mechanism which includes a body, a retaining member which is pivotally mounted to the body on a first axis, a biasing member which is pivotally mounted to the body on a second axis which is parallel to the first axis and which bears against the retaining member, and biasing means which acts between the body and the biasing member urging the biasing member towards a first position relatively to the body.

1 The retaining member may include two luas which engage with a snap action respectively in two spaced slots. The retaining member may thus pivot about the first axis which is formed by the interconnection of the lugs with the slots.

The biasing member may have two spaced opposed wings and the retaining member may be slidably posil.ior-.,G:-- between the wings.

The retaining member may include a passage which is adapted to engage with a shaft so that pivotal movement of the shaft is transferred to the retaining member, and vice versa. For this purpose the passage may include a flat or any suitable formation which engages with a complementary formation on the shaft.

If 3 The body may include a flexible portion which permits the body to be positioned in a cutout in sheet metal and which then acts as a stop to prevent the body from being withdrawn from the cutout.

The invention also extends to a locking system for a drawer which is mounted in a cabinet which includes a catch mechanism of the aforementioned kind fixed to the cabinet, a cam which is fixed to the drawer and which engages with and moves the biasing member to an inoperative position, when the drawer is in a closed position, and a biasing device which acts on the retaining member urging it out of engagement with the cam, when the biasing member is in the said inoperative position, so that the drawer can be opened, and the cam engaging with the retaining member., when the retaining mernber is in the said first position, whereby the drawer is prevented from being opened.

The invention is further described by L.,ay of example with reference to the accompanying drawings in which:

Figure 1. illustrates a locking system for a drawer which includes a catch mechanism according to the invention, with the drawer in a closed but openable position, 4 Figure 2 is a view similar to Figure 1 but with the drawer partly opened, and Figure 3 is a side view of the catch mechanism which is illustrated in plan in Figures 1 and 2.

is The accompanying drawings illustrate portion of a drawer 10 which is mounted in a cabinet not shown in detail but which includes a frame leg 12. The drawer is mounted in the cabinet in any appropriate way, which is known per se, and which for this reason is not further described herein.

The drawer 10 is made at least partly from sheet metal and on one side the sheet metal has an aperture 14 cut from it. A cam member 16 is engaged with the aperture. The cam member includes a cam formation 18, an undercut projection 20 which engages with a rim of the sheet metal, shown in dotted ou;'ne. adjacent the aperture, and a retaining clip 22 which has a hook formaiion 24 which also engages with a rim of the sheet metal adjacent the aperture.

Alongside the drawer, mounted to the frame leg 12, is a catch mechanism 25. The catch mechanism is shown in plan in Figures 1 and 2 and from the side in Figure 3.

1 t The catch mechanism includes a body 26, a retaining member 28 and a biasing member 30.

1 The body 26 is formed with two spaced slots 32, only one of which is visible in Figures 1 and 2, and the retaining member 28 has two circular lugs 34 which project from opposing sides of the retaining member and which are engageable with a snap action in the slots 32. The retaining member 28 is then pivotal to a limited extent relatively to the body 26 about a first axis which is defined by the interconnection of the lugs with the slots.

A passage 36 extends through the retaining member 28, concentrically with the lugs. The passage has an inner flat surface 38. A shaft 39. shown in Figure 3, is insertable into the passage. This shaft is complementary in outline to the crossr sectIonal sh.ape of the passage. Consequently rotational movement of the shaft is transferred to the member 28, and vice versa.

The retaining member at an end remote from the passage includes a catch formation 40, see Figure 2.

The biasing member 30 is mounted to the body for pivotal movement about a second axis 42 shown in dotted outline in Figures 1 and 2. This 6 axis is defined by spigots on the biasing member which engage with complementary formations in opposed surfaces 44 and 46 of the body, see Figure 3. A spring 48 mounted on one of the spigots has extension pieces 50 and 52 which act on surfaces of the body and the biasing member.

The biasing member further includes opposed wings 54, only one of which is visible in Figures 1 and 2, and the catch formation 40 and the portion of'the retaining member 28 adjacent the catch formation, are slidably engaged with the biasing member between the wings 54.

The body 2e includes a flexible portion 56 on a spigot 58 of square cross section. As shown in Figures 1 and 2 the spigot 58 is insertable into complementarv f ormations in the frame leg 12 and the flexible portion 56 then engageS a spring action with a surface of the frame leg adjacent one of the aDertures to keep the catch mechanism firmly secured to the frame leg.

A number of the catch mechanisms 24 are located on the shaft 39 at spaced intervals. Each catch mechanism is engageable with a respective cam member 16 mounted to a respective drawer in the cabinet. Each of the drawers is movable independently of the other drawers. The catch mechanisms are mounted one above the other to the frame leg 12. As 7 relative movement between any retaining member 28 and the shaft is not permitted it follows that all of the retaining members 28 are movable in unison. On the other hand the biasing members 30 are independently movable. The spring 48 which acts on each biasing member tends to rotate the biasing member in an anti-clockwise direction as shown by an arrow 60 in Figure 2. On the other hand the shaft 39 has a spring 61 connected to it, see Figure 3, which tends to rotate the retaining member 28 in a clockwise direction 62, as shown in Figures 2 and 3. The body 26 is, as has been noted. fixed to the frame leg.

When all the drawers in the cabinet are closed, as shown for the drawer 10 in Figure 1, the cam 18 on the cam memb-er 16 acts on the wings 54 of the biasing member and moves the biasing membel in a clockwise direction to the position shown in Figure 1. The spring 61 which acts on the shaft 39 automatically causes each of the retaining members to move together with the biasing members so that the catch formations 40 are contained within the wings 54. Thus, as is shown in Figure 1, each of the drawers 10 can be withdrawn and the respective catch mechanism 24 does not impede the movement of the drawer.

On the other hand when a drawer is moved to an open position the respective cam 18 is moved out of engagement with the respective wings 54 and the respective biasing member 30 then pivots in an anti-clockwise 8 direction 60 about the second axis 42. The biasing member thus acts on the respective retaining member 28 and urges it in an anti-clockwise direction as well. The shaft 39 is rotated by the same angular extent, in an anti-clockwise direction, and each of the retaining members is simultaneously rotated in an-anti-clockwise direction. The various catch formations 40 of the retaining members 28 are thus moved to dotted line positions 40A shown in Figure 1. At these positions each of the catch formations 40 is positioned so that it is in line with the cams 18 on each of the respective drawers and, if any attempt is made to open any of these drawers. the respective cam is brought into abutment with the associated catch formation and the drawer is restrained from being opened.

It follows from the aforementioned description that if one drawer is opened all; of the retaining members 28 are moved to positions at which -=.-na:ning drawers are prevented from being opened. On the other hand when the open drawer is closed the respective retaining member 28 is moved away from the dotted line position 40A shown in Figure 1 to the retracted position between the wings 54 shown in Figure 1, and, in so doing. the shaft and all of the retaining members which are engaged with the shaft are rotated in a clockwise direction so that the respective catch formations 40 are moved away from the positions at which they are in line with the respective cams 18 and at which the various drawers are prevented from being opened, to retracted positions at which any one of i- t, 9 the drawers can be opened.

The catch mechanism of the invention thus provides a safety device in that it permits only one drawer in a cabinet of drawers to be opened at a time. Any other drawer can only be opened when all of the remaining drawers are moved to closed positions.

Claims

1. A catch mechanism which includes a body, a retaining member which is pivotally mounted to the body on a first axis, a biasing member which is pivotally mounted to the body on a second axis which is parallel to the first axis and which bears against the retaining member, and biasing means which acts between the body and the biasing member, urging the biasing member towards a first position relatively to the body.

2. A catch mechanism according to claim 1 wherein th e retaining member includes two lugs which engage with a snap action respectively in t\..,vo spaced slots in the body thereby defining the first axis.

3. A catch rnechanism according to claim 1 or 2 wherein the biasing member has two spaced opposed wings and the retaining member is slidably positioned between the wings.

4. A catch mechanism according to claim 1, 2 or 3 wherein the retaining member includes a passage which is positioned on the first axis and which is adapted to engage with a shaft so that pivotal movement of the shaft is transferred to the retaining member, and vice versa.

11 1 5. A catch mechanism according to any one of claims 1 to 4 wherein the body includes a flexible portion which permits the body to be positioned in a cutout in sheet metal and which then acts as a stop to prevent the body from being withdrawn from the cutout.

6. A locking system for a drawer which is mounted in a cabinet which includes a catch mechanism according to any one of claims 1 to 5 fixed to the cabinet, a cam which is fixed to the drawer and which engages with and moves the biasing member to an inoperative position, when the drawer is in a closed position, and a biasing device which acts on the retaining member urging it out of engagement with the cam, when the biasing member is in the said inoperative position, so that the drawer can be opened, and the cam engaging with the retaining member. when the retaining member is in the said first position, whereby the dravier is prevented from being opened.

7. A locking system for a cabinet which has a plurality of drawers, the locking system including a plurality of cams, each cam being fixed to a respective drawer, a plurality of catch mechanisms, each catch mechanism being according to claim 4, and each catch mechanism being associated with a respective drawer and a respective cam, a shaft which is engaged with each said passage in the retaining members, and a biasing device which acts on the shaft in a direction which is opposite to 12 is the direction in which the respective said biasing means act on the respective biasing members, and wherein, when all the drawers are closed, each cam is engaged with the respective biasing member so that all the retaining members are urged, by the biasing device which acts on the shaft, out of engagement with the respective cams, and wherein, when any one drawer is opened, the respective cam is moved out of engagement with the respective biasing member which then acts on the respective retaining member urging it, and all the remaining retaining members, against the action of the biasing device which acts on the shaft, to positions at which the said remaining retaining members are engageable with the respective cams to prevent the associated drawers from being opened.

8. A catch mechanism substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.

9. A locking system as claimed in Claim 6 wherein the catch mechanism is as claimed in Claim 8.

10. A locking system as claimed in Claim 7 wherein the catch mechanism is as claimed in Claim 8.

11. A locking system substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.

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