GB2155092A

GB2155092A - Door safety device

Info

Publication number: GB2155092A
Application number: GB08404142A
Authority: GB
Inventors: Gerald Arthur Oatley
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-02-16
Filing date: 1984-02-16
Publication date: 1985-09-18
Also published as: GB8404142D0

Abstract

A hinged door 1 has a safety device to reduce the risk, when the door closes, of fingers being trapped, particularly at the hinged end of the door. The safety device comprises a bolt 4 which is spring-loaded so that it normally protrudes beyond the edge of the door and strikes the door frame 2 before the door closes to a dangerous extent. The bolt 4 is coupled by a Bowden cable 7 or other linkage to the door handle 3. The bolt 4 can be withdrawn, to allow the door to close, by turning the door handle to retract the latch. A deliberate act of retracting the door latch is therefore required before the door can be shut. The bolt 4 may be made up of rubber or other resilient material to avoid damage to the frame. The actuating mechanism 6 for withdrawing the bolt 4 may be separate from the latch mechanism and mounted between the door surface and the usual face plate surrounding the spindle of the door latch. <IMAGE>

Description

SPECIFICATION Door safety device This invention relates to a safety device for hinged doors to reduce the risk, when the door closes, of fingers being trapped, particularly, though not exclusively at the hinged edge of the door.

The present invention consists in a safety device for hinged doors comprising means normally preventing closure of the door, at least to a dangerous extent, and means operatively coupled to means for retracting a door latch for rendering the safety device inoperative when the door latch is retracted.

The safety device thus requires a deliberate act of retracting the door latch before the door can be shut.

The means normally preventing closure of the door may be a bolt mounted on the door and spring urged towards an operative position in which the bolt engages the frame to which the door is hinged and so prevents closure. The bolt may be coupled to a handle for operating the door latch by a Bowden cable or other convenient means.

in one embodiment of the invention suitable for mounting on a door already provided with a latch a Bowden cable is connected at one end to the spring loaded bolt and at the other end to an actuating device coupled to a spindle of the latch. The actuating device may be interposed between the handle and the face of the door and comprise a radial arm movable angularly by the latch spindle and arranged at its radially outer end to operate the Bowden cable.

An embodiment of the invention will now be describded by way of example with reference to the accompanying drawings, in which: Figure 1 shows a door fitted with a safety device according to the invention; Figure 2 is a plan view of a bracket incorporated in the safety device; Figure 3 is an end view of the bracket; Figure 4 is a fragmentary plan view showing a bolt of the safety device in an operative position; Figure 5 is a section on the line A-A of Figure 4; Figure 6 is a fragmentary end view of the safety device showing the bolt in an inoperative position; Figure 7 is a front view partly in section of an actuating mechanism of the safety device; Figure 8 is an inverted plan view of the actuating mechanism; Figure 9 is a section on line B-B of Figure 7;; Figure 10 is an enlarged fragmentary plan section of part of the actuating mechanism; Figure 11 is a plan view of the safety device in the operative position; and Figure 12 is a plan view of the safety device in the inoperative position.

The door shown in Figure 1 and indicated by the reference 1 is hinged on one side to a door frame 2 and has a door handle 3 for operating a latch (not shown). The bolt, actuating mechanism and bracket are indicated by reference numerals 4, 6 and 8 respectively. The safety device comprises the bolt 4 housed in a casing 5, and the actuating mechanism 6, interconnected by a Bowden cable 7.

Slack in the cable is taken up by the bracket 8, so that the same length of cable can be used with a variety of sizes of doors. The bracket 8, which is preferably formed of poiypropylene, is shown in detail in Figures 2 and 3. It has an attachment part 9 of L-shaped cross-section which fits over and is fixed to the top edge of the door 1, and a tubular guide part 10 through which the cable 7 passes.

The bolt 4 and the casing 5 are shown in detail in Figures 4,5 and 6. The bolt is of a resilient material such as rubber and the casing is of metal or a suitable plastics material such as polypropylene.

The casing 5 has an attachment part 11 which, like the attachment part 9 of the bracket 8, is of L-shaped cross-section and fits over and is fixed to the top edge of the door 1. Integrally formed with the attachment part 11 is a main body part 12 for housing the bolt 4. The main body part is of generally D-shaped cross-section, having a peripheral wall 13 comprising a straight part 14, which rests against a face of the door 1, and a curved part 15, integral with a base 16. At its upper edge the curved part 15 has, on opposite sides close to the straight part 14, D-shaped cut-away portions 17. Two spaced, longitudinally extending guide ribs 18 and 19 project inwardly from the straight part 14 of the peripheral wall.

The bolt 4 is also of generally D-shaped crosssection and fits with clearance within the main body part 12 of the casing 5. The bolt has two grooves 20 and 21 which receive the guide ribs 18 and 19 respectively.

The bolt has an axial bore 22 of stepped diameter, comprising an inner bore 23 opening onto the inner face of the bolt, an outer bore 24 opening onto the outer face of the bolt and an intermediate bore 25 of reduced diameter interconnecting the inner and outer bores.

One end of a compression spring 26 abuts the bolt at a first step between the inner bore 23 and the intermediate bore 25. At its other end the spring abuts the base 16 of the casing. The base incorporates a tubular socket 27 which is co-axial with the stepped bore 22 and the end of the spring abutting the casing surrounds the socket.

The socket 27 receives the Bowden cable 7 comprising an inner cable 28 and an outer tubular sheath 29. The inner cable extends through an opening 30 in the socket, and through the stepped bore 22. A nipple 31 at one end of the inner cable is retained in the outer bore 24 by means of a washer 32 having a U-shaped slot 33, which rests against a second step between the outer bore 24 and the intermediate bore 25.

Referring now to Figures 7 to 10, the actuating mechanism 6 comprises a moulding 34 of a plastics material. The moulding has a base part 35 of generally circular outline which is fixed to the face of the door 1, and a casing part 36 which is integral with and arranged at one side of the base part 35.

The base part has a circular opening 37 at its centre. A square spindle 38 for operating the latch of the door 1 extends through the circular opening with sufficient clearance to allow the spindle to rotate freely.

The base part 35 is of two different thicknesses, comprising a thinner part 39 and a thicker part 40.

The thinner part acts as a spacer between the door 1 and an arm 41 providing a bearing surfaceforthe arm. The arm has an enlarged end portion 42 of generally circular shape. A square opening 43 at the centre of the end portion 42 fits over the spindle 38, so that rotation of the spindle can be transmitted to the lever arm, the end portion 42 covering the opening 37 in the moulding.

The thicker part 40 of the base part acts as a spacer between the door 1 and a face plate (not shown), the spindle 38 extending through the face plate to be attached to the door handle 3. Clearances 44 are provided in the thicker part 40 for screws for fixing the face plate to the door. A face plate is usually provided between a door handle and the door to which it is attached. Many face piates are round but if the face plate is rectangular, the screws fixing the face plate to the door will generally be arranged outside the area of the base part 35, rather than passing through the clearances 44. In that case, a filler strip, for example of plastics or wood, could be cut to support the face plate outside the base part.

Two angularly spaced steps, an upper step 45 and a lower step 46, between the thinner part 39 and the part 40 of the base part act as stops for limiting the rotation of the lever arem 41.

The lever arm 41 extends into the casing part 36 of the moulding 34. At its end within the casing part the lever arm has a circular aperture 47.

The pivotable stud 48 shown in detail in Figure 10 passes through the aperture 47 and is retained on the lever arm by a circlip 49. A U-shaped slot 50 extends th rough the stud.

The casing part 36 has cable locating means 51 at its upper and lower ends, each comprising a socket 52 having a base 53. A U-shaped slot 54 in the base 53 and a corresponding slot 55 extending along the length of the socket 52 open onto that face of the casing part which is adjacent to the door 1.

The inner cable 28 and the outer tubular sheath 29 of the cable 7 are located in the socket 52 of the upper cable locating means. The inner cable passes with clearance through the U-shaped slot 54 in the base of the socket and the U-shaped slot 50 in the stud 48, and is retained within the slot 50 in the stud by means of a nipple 56 provided at that end of the cable which is within the casing part 36.

The arrangement shown in the drawings is a right-hand fitting. A left-hand fitting, suitable for a door hinged on the side opposite to that shown, is obtained simply by rotating the moulding 34 through 180 about the spindle 38 and turning the lever arm 41 over, to obtain a mirror image of the arrangement illustrated. The cable is then received in the other of the cable locating means to that used for the left-hand fitting.

In the operative position shown in Figures 4, 5 and 11, the bolt 4 is urged by the compression spring 26 into a position in which it projects from the casing 5, so that it abuts against the side of a rebate 57 at the top of the door frame 2 to prevent closure of the door 1. The bolt is so positioned on the door that in the operative position it maintains a large enough gap between the hinged edges of the door and the door frame to prevent fingers from being trapped therein.

The material of the bolt is soft enough not to cause any damage to paintwork on the door frame, but this means that the bolt deforms when squeezed between the door 1 and the step 57. It is desirable to minimise the stresses produced in the casing 5 due to deformation of the bolt, particularly since a light casing is preferred. That is why the bolt is not closely confined, but fits with clearance, within the casing. When squeezed between the door and the door frame, the bolt tends to move towards the side of the casing having the cut-away portion 17 but this tendency is resisted by engagement of the channel grooves 20 and 21 in the bolt with the guide ribs 18 and 19 in the casing. In this way, some clearance is preserved between the bolt and that side of the casing, to provide for deformation of the bolt, which can expand through one or both of the cut-away portions 17.

When the bolt 4 is in the operative position, the actuating mechanism 6 is as shown in Figure 7, with the lever arm 41 abutting against the upper step 45.

A positive action is required in order to close the door 1. The door handle 3 has to be turned, so that the spindle 38 and the arm 41 are rotated. As the arm 41 rotates, the stud 48 pushes the nipple 56 downwards, pulling the inner cable 28 further into the casing part 36 of the moulding 34, the stud pivoting within the aperture 47 in the lever arm. The inner cable 28 is thereby withdrawn from the casing 5, the nipple 31 exerting a downward force on the bolt 4 through the washer 32, so that the bolt is itseif withdrawn into the casing to clear the rebate 57 in the door frame. Of course, turning the door handle on the opposite face of the door has the same effect.

When the door is closed and the door handle is released, the spring on the door latch causes the spindle 38 and the arm 41 to return to their original positions. However, the bolt 4 is prevented from returning to its operative position by engagement with the door frame close to the rebate 57, so that the inner cable 28 remains in a lowered position within the casing part 36 of the moulding. The inoperative position is shown in Figures 6 and 12 of the drawings.

Normally, when the door is closed there will be a gap between the door and the top of the door frame providing enough room for the attachment parts 9 and 11 of the bracket 8 and the casing 5 respectively.

When the door handle is turned to allow the door 1 to be opened the lever arm 41 again rotates and picks up the nipple 56 retracting the bolt to the fully inoperative position against the action of the spring 26. When the door handle is released the spring 26 urges the bolt 4 into the extended, operative position.

The safety device is easy to install and to remove from the door. As the casing 5 and the bracket 8 are fixed to the top edge of the door, and the moulding 34 is fixed to the door behind the face plate forthe door handle, no disfiguring marks are visible on the door when the safety device is removed.

Claims

1. A safety device for hinged doors comprising means normally preventing closure of the door, at least to a dangerous extent, and means operatively coupled to means for retracting a door latch for rendering the safety device inoperative when the door latch is retracted.

2. A.safety device according to claim 1 wherein the means for rendering the safety device inoperative comprises an actuating device coupled to a rotary spindle actuating the door latch.

3. A safety device according to claim 2 wherein the actuating device is adapted to be used with a separate door latch.

4. A safety device according to claim 3 wherein the actuating device is adapted to be interposed between the handle and the face of the door.

5. A safety device according to claim 4 wherein the actuating device comprises a body adapted to be mounted between the face of the door and a face plate through which the spindle of the door latch extends to a handle and which covers the body of the actuating device.

6. A safety device according to any one of preceding claims 2 to 5 wherein the actuating device comprises a radial arm movable angularly by the latch spindle and arranged at its radially outer end to be operatively coupled to the means for preventing closure of the door.

7. A safety device according to claim 6 wherein the spindle of the door latch by which the radial arm is movable angularly, or adapted to be moved angularly, is of non-circular cross-section which is engaged by a complementary opening at the radially inner end of the radial arm.

8. A safety device according to claim 7 wherein the spindle cross-section is symmetrical about a transverse axis of symmetry and the radial axis of the arm is angularly displaced with respect to a corresponding transverse axis of symmetry of the complementary opening, the arrangement being such that, by turning the radial arm over, the radial arm can be engaged with the spindle in either of two angular positions in which its radial axis is angularly displaced on opposite sides of the axis of symmetry of the spindle cross-section.

9. A safety device according to any one of claims 6 to 8 wherein the or a body of the actuating means is adapted to be mounted on the face of the door and includes at least one mounting for a member forming part of the operative coupling between the outer end of the radial arm and the means for preventing closure of the door.

10. A safety device according to claims 8 and 9 wherein the body can receive the radial arm in each of its two angular positions with respect to the spindle, the arrangement being such that the actuating device can be suitably assembled for mounting on a door hinged on the right or the left.

11. A safety device according to any preceding claim wherein the means normally preventing closure of the door is a bolt mounted on the door and movable towards an operative position in which the bolt protrudes beyond the edge of the door to engage the frame to which the door is hinged, and so prevent closure.

12. A safety device according to claim 11 wherein the bolt is spring urged towards the operative position.

13. A safety device according to claim 11 or claim 12 wherein for movement towards its operative position the bolt is slidably mounted in a casing adapted to be secured to the door.

14. A safety device according to claim 13 wherein the bolt is of D-shaped cross-section and the casing has a cavity of complementary shape in which the bolt is slidably received, the casing being adapted to be mounted on the door with the flat side of the Dshaped cavity parallel to the face of the door.

15. A safety device according to claim 14 wherein at least one guide rib and a groove to receive it is provided between the confronting flat surfaces of the bolt and the cavity of the casing, the rib and groove being directed and axially slidable one in the other in the direction of sliding movement of the bolt.

16. A safety device according to any preceding claim wherein the bolt is made of flexible, resilient material.

17.Asafetydevice according to claim 16 as appendant to claim 13 wherein the wall of the cavity in the casing has a cut-away portion or portions through which material of the bolt can expand when deformed by being squeezed between the door and the frame.

18. Asafety device according to any one of preceding claims 13 to 17 wherein the casing is arranged to be mounted on the door by an attachment portion which is adapted to fit over and be fixed to the top edge of the door.

19. A safety device according to any preceding claim wherein lost motion is provided between the means normally preventing closure of the door and the means for retracting the door latch, the arrangement being such as to allow independent movement of the means for preventing closure of the door and the means for retracting the door latch except in the direction for rendering the safety device inoperative on retracting the door latch.

20. A safety device according to any preceding claim wherein the operative coupling between the means normally preventing closure of the door and the means for retracting the door latch is a Bowden cable.

21. A safety device sunstantially as herein described with reference to and as illustrated by the accompanying drawings.