GB2173850A - Child-proof catch - Google Patents

Abstract

A child-proof catch for releasably securing e,g. a door to e.g. a door frame, the catch comprising: a first portion 5 secured to the door 3 and providing a hook 7 biassed by spring 10 having a strip of magnetizable material 11 rigidly associated therewith; a second portion 12 secured to the door frame 4 and providing an engagement plate 14 and a magnet 16; the first and second portions being dimensioned and arranged such that the hook is pivotable between a first position in which the magnetizable material 11 and the magnet 16 are spaced apart and the hook is engaged with the engagement plate Fig. 1, and a second position (Fig. 2) in which the magnetizable material contacts the magnet and the hook is disengaged from the engagement plate; the catch further comprises a resilient stop 15 secured to either the door or the frame against which the door is pushed to bring material 11 and magnet 16 together. <IMAGE>

Description

SPECIFICATION Child-proof catch Background of the Invention 1) Field of the Invention The present invention relates to a catch for a door (especially a cupboard door,) or a drawer, or a gate said catch being 'childproof' in the sense that it is impossible, or at worst extremely difficult, for a young child to undo the catch.

A satisfactory child-proof catch must not only be extremely diiiicult (preferably impossible) ior a young child to undo, but must also be easily operated by older children and adults:- if the catch is difficult for all ages to use, it will have little advantage over simply securing the cupboard or drawer with a lock and key or with a padlock. Further, the catch should not disfigure the furniture to which it is fitted, because many people are reluctant to mark expensive furniture, even in the interest of safety.

The catch also should be capable of being fitted to existing furniture:- clearly, there is a limited scope of usefuliness for a catch which can be incorporated only in a specially-designed piece of furniture.

2) Description of the Prior Art US patent no: 3888525 discloses a cupboard or drawer catch which comprises a curved spring one end of which is secured at one end to a drawer or cupboard door and the other end of which is biassed into engagement with a rigid projection secured to the drawer-frame or door-frame. A user must apply force to the spring against the biassing force to release the catch and open the drawer or cupboard.

This catch has proved to be reasonably convenient for drawers, but inconvenient to use on most cupboards, and indeed, impossible to fit to some designs of cupboard.

US patent no: 3909050 discloses a cupboard catch which includes a pivoted hook secured to a cupboard door frame, the hook being releasably engaged with an abutment secured to the cupboard door. The door can be opened by manually disengaging the hook from the abutment. The whole catch is concealed and made child-proof by a housing; access to the hook can be obtained only by opening the front door of the housing, which is designed to be difficult or impossible for small children to open.

This design has the drawback that the catch must be mounted on the outside of the door, thus disfiguring the furniture.

Brief Summary of the Invention An object of the present invention is the provision of a child-proof safety catch for doors, (especially cupboard doors) or gates or drawers,which is easy to fit, does not disfigure the furniture, and is reliable and easy to use by an adult or older child.

The present invention provides a child-proof catch for releasably securing a first member such as a door or gate or drawer to a second member, such as a door frame, shelf gatepost or drawer frame, said catch comprising: a first portion securable to one of said first or second members and a second portion securable to the other of said first or second members, said first portion comprising: a hook having one of a magnet or a strip of magnetizable material rigidly associated therewith; said second portion comprising an engagement plate and the other of a magnet or a strip of magnetizable material; said first and second portions being dimensioned and arranged such that said hook is pivotable between a first position in which the magnetizable material and the magnet are spaced apart and the hook is engaged with the engagement plate so as to secure said first and second members together, and a second position in which the magnetizable material and the magnet are closer together than in said first position and the hook is disengaged from the engagement plate; said hook being biassed towards said first position; and a resilient stop securable to the first or the second member so as to prevent the first and second members being in contact adjacent the catch when said hook is in said first position.

Brief Description of the Drawings By way of example only, a preferred embodiment of the present invention is described in detail, with reference to the accompanying drawings, in which: Fig. 1 is a plan view of a catch in accordance with the present invention fitted to the side edge of a cupboard door and the corresponding portion of the door frame. For clarity, the upper horizontal member of the door frame has been removed: the catch is in the 'closed' position Fig. 2 is a plan view as in Fig. 1 but with the catch in the 'open' position.

Fig. 3 is a side view of the part of the catch secured to the frame.

Description of the Preferred Embodiment Referring to the drawings, a safety catch 2 in accordance with the present invention is shown fitted to a cupboard door of the facehung type, in which the door 3 overlaps the frame 4. The catch may be secured at any position around the perimeter of the door, but preferably is secured to the side edge of the door, adjacent the top edge, as shown. This position of the catch makes the catch as difficult as possible for a young child to undo.

The portion of the catch 2 which is secured to the door 3 includes a first mounting plate 5, the plane of which is parallel to the plane of the door 3; the mounting plate is provided with holes through which nails or screws are inserted to secure the mounting plate to the door. A pair of spaced parallel support plates 6 are formed integrally with the mounting plate; the plane of each plate 6 is perpendicular to the plane of the mounting plate. A hook 7 and arm 8, formed integrally, are pivotally mounted between the support plates 6 by a pivot pin 9, so as to be pivotable between the closed position shown in Fig. 1 and the open position shown in Fig. 2. The hook is biassed towards the closed position by a coil spring 10 mounted between the plates 6 and engaged between the mounting plate 5 and the portion of the hook 7 adjacent the pivot pin 9.

The hook 7 comprises a stalk 7a supporting an engagement face 7b which extends perpendicular to said stalk. In the closed position, the face 7b is inclined slightly towards the plane of the mounting plae 5. The rear face 7c of the hook is smoothly curved.

The arm 8 curves round to extend beyond the face 7b, substantially parallel to the mounting plate. The end of the arm 8 carries a strip 11 of magnetizable material (e.g. ferritic steel).

The portion of the catch 2 secured to the door frame 4 includes a second mounting plate 12 which ends flush with the front edge 8 of the frame and is formed with one or more pairs of holes through which screws or nails are inserted to secure the mounting plate to the frame. One pair of holes may be slots.

The plate 12 supports a housing 13 which contains a permanent magnet 16 arranged op polite the strip 11 of magnetizable material.

The surface of the housing opposite the plate 12 is provided with a wedge-shaped engagement plate 14 which is arranged with the thin edge of the wedge adjacent the edge of the housing 13 which is closest to the door.

A resilient stop 15 is secured to the door frame vertically below the plate 12 and spaced a short distance below said plate. The stop 15 is arranged so as to project a short distance beyond the frame 4 so that when the door is closed, the interior surface of the door rests on the stop rather than contacting the frame, as shown in Fig. 1 and 2. The stop 15 may be made of any suitable tough, resilient material (e.g. rubber, plastics). The stop 15 could be of any shape, providing it can form a firm but resilient stop, but preferably the stop 15 comprises a washer which is circular in plan and is formed with an off-centre hole through which a screw is inserted to secure the washer two the frame.If the hole is formed off-centre, the distance by which the washer projects beyond the edge of the frame can be altered simply by loosening the screw, rotating the washer to the desired position, and retightening the screw.

The further the stop projects beyond the frame, and the closer the stop is to the plate 12, the more difficult it is to release the catch, as described below.

The surface of the washer which contacts the frame may be formed with a step in- its circumference, so that the step engages with the edge of the frame and ensures correct positioning of the washer for a specified type of door.

An alternative embodiment of the stop 15 comprises part of a helical coil of plastics material, secured to the door through the first turn of the coil.

The above-described catch operates as follows: when the door is open, the hook 7 is biassed by the spring towards the position of Fig. 1. When the door is swung towards the frame, to close the door, the curved rear face 7c rides up the wedge-shaped engagement plate 14 until the engagement face 7b of the hook passes beyond the rear of the plate 14 and said face 7c lies behind the flat rear face of the thick end of the wedge, thus holding the hook in engagement with the plate 14 and fastening the door closed. In this position, the stop 15 holds the door 3 a short distance (typically 4mm) away from the frame 4, and the magnetizable strip 1 1 is spaced a sufficient distance from the magnet 16 that said strip is not moved towards the magnet. In this position, the door is securely latched, and cannot be opened simply by pulling on the door handle.

To release the catch and open the door, it is necessary to press the door towards the frame against the resilience of the stop 15, (i.e. in the direction of arrow F) to close the gap between the door and the frame and bring the magnetizable strip 11 close enough to the magnet 16 for the magnet to attract the strip 11 to it, thus pivoting the hook 7 in the direction of arrow A of Fig. 1, and releasing the face 7b from engagement with the plate 14. The door can now be opened by pulling on the handle with sufficient force to break the magnetic attraction between the strip 11 and the magnet 16. Once this attraction is broken, the spring 10 automatically returns the hook 7 to the position shown in Fig.

1.

The above-described catch is difficult or impossible for a small child to operate because the force required to press the door towards the frame against the resilience of the stop 15 is greater than can easily be exerted by a small child. Also, said force must be applied at some point above the stop 15, and it is not easy for a small child to apply force so precisely. Ciearly, the greater the spacing between the door and the frame caused by stop 15, the greater the force required to release the catch. Also, the closer the stop 15 is to the plate 12, the greater the force needed to release the catch, because a smaller portion of the door is available to be flexed towards the frame.

Another safety feature of the catch of the present invention is that the door does not spring open once the hook 7 has been disengaged from the plate 14:- the door is still held closed by the magnetic attraction between the strip 11 and plate 12, and a person opening the door must pull on the door handle to break this attraction. This means that it is not obvious to a small child that pressing the door towards the frame releases the catch, because the door still appears latched even after the correct pressure has been applied.

The catch may be secured along the top or bottom edges of a door or at any point along the side edge, with the 'frame' portion of the catch secured either to the corresponding portion of the frame or to an interior shelf or similar fitting. However, it is preferred to secure the catch in the position described with reference to the drawings, because that location of the catch reduces the possibility of a small child falling against the door and accidentally applying the necessary pressure in the correct place.

The catch can be fitted to flush-hung doors as well as to face-hung doors, and can also be fitted to drawers. It will be appreciated that more than one catch could be fitted to a door or drawer.

As an additional safety precaution, it is preferred that the cupboard door be hung with self-closing hinges, so that the door cannot be left open accidentally.

The catch (excluding the strip 11 and magnet 16) may be may of any suitable material e.g. glass-filled nylon or acetal resin.

The above described catch may be secured to the door and frame by adhesive instead of, or as well as, screws or nails. Double-sided adhesive tape is particularly easy to use for this purpose.

The catch is designed to be easy to fit even by the unskilled. It is of course essential that the spacing between the strip 11 and magnet 16 is correct, because otherwise the catch will not work properly, and to ensure that the catch is always fitted correctly, the plate 12 is so dimensioned that if the edge of that plate is flush with the edge of the frame (or shelf), the strip 11 and magnet 16 will be the correct distance apart. To ensure that the hook is correctly positioned, a guide channel 17 is formed in the plate 12. A sharp-pointed marker (e.g. a nail) is snapped into channel 17, the plate 12 is secured to the frame, and the door is closed gently to the frame, so that the marker marks the opposite surface of the door. This mark is then aligned with a reference mark on plate 5 or a protrusion formed on the underside of plate 5, to ensure that the plate 5 is secured in the correct position on the door. The marker is removed before the catch is used.

The catch may be fitted the opposite way round to that described i.e. the portion including the hook 7 mounted on the frame, and the plate 12 and magnet 16 on the door, if this suits the furniture to which the catch is to be fitted.

Claims (11)

1. A child-proof catch for releasably securing a first member such as a door or gate or drawer to a second member such as a door frame, shelf, gatepost, or drawer frame, said catch comprising: a first portion securable to one of said first or second members and a second portion securable to the other of said first or second members, said first portion comprising: a hook having one of a magnet or a strip of magnetizable material rigidly associated therewith; said second portion comprising an engagement plate and the other of a magnet or a strip of magnetizable material; said first and second portions being dimensioned and arranged such that said hook is pivotable between a first position in which the magnetizable material and the magnet are spaced apart and the hook is engaged with the engagement plate so as to secure said first and second members together, and a second position in which the magnetizable material and the magnet are closer together than in said first position and the hook is disengaged from the engagement plate; said hook being biassed towards said first position; and a resilient stop securable to the first or the second member so as to prevent the first and second members being in contact adjacent the catch when said hook is in said first position.

2. A catch as claimed in Claim 1 wherein in said first portion, the magnet or magnetizable material is mounted upon an arm which is rigidly secured to the hook; and the pivot about which said hook pivots between said first and second positions is located between said hook and said magnet or magnetizable material.

3. A catch as claimed in Claim 1 or Claim 2 wherein said engagement plate is substantially wedge-shaped and said hook in said first po- sition engages the face of the thick end of the wedge.

4. A catch as claimed in any preceding claim wherein in said second position the magnet is in contact with the magnetizable material.

5. A catch as claimed in any preceding claim wherein the resilient stop is circular in plan and is formed with an off-centre hole through which said stop is securable to said first or second member.

6. A catch as claimed in any one of Claims 1-4 wherein the resilient stop comprises a portion of a helical coil spring which is securable to said first or second member at the inner end of said coil.

7. A catch as claimed in any preceding claim wherein said second portion further comprises a mounting plate the outer edge of which lies flush with the edge of said first or second member when said second portion is secured thereto.

8. A catch as claimed in Claim 7 wherein said mounting plate is adapted to receive a removable sharppointed marker for correctly positioning said first portion of the catch relative to said second portion.

9. A method of releasably securing a first member to a second member by means of a child-proof catch, said method comprising:

1. Providing a catch as claimed in Claim 1;

2. Securing the first portion of the catch to one of the first or second members;

3. Securing the second portion of the catch to the other of the first or second members; 4.Securing the resilient stop to the first or the second member, said stop being located and arranged such that when said hook is in said first position, said first and second members are spaced apart adjacent the catch; wherein said hook is pivoted from said first position to said second position by external force applied to urge first and second members together so that the magnet and the magnetizable material approach each other sufficiently closely for the magnetizable material to be pivoted closer to the magnet, thus pivoting the hook out of engagement with the engagement plate and release said catch.

10. A child-proof catch substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

11. A method of releasably securing a first member to a second member by means of a child-proof catch substantially as hereinbefore described with reference to and as shown in the accompanying drawings.