GB2318383A

GB2318383A - Shoot bolt mechanism for a door

Info

Publication number: GB2318383A
Application number: GB9621519A
Authority: GB
Inventors: Giuseppe Megna
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-10-16
Filing date: 1996-10-16
Publication date: 1998-04-22
Anticipated expiration: 2016-10-16
Also published as: GB2318383B; GB9621519D0

Abstract

A security system 10 for a door comprises a box 11 and rectilinear rods 46,47 extending upwardly and downwardly from the box and each being movable, by a rotary mechanism 30 comprising arms 32,33, the ends 34,35 of which engage in guides 26 (slots) to operate further arms 22,23. The arms 22,23 engage sliders 42,43 which in turn move the rods 46,47 longitudinally against spring biasing 44,45 so that remote end portions of the rods 46,47 locate in tracks which thereby restrict opening of the door beyond a pre-determined limit. A pawl 38 can be engaged in a detent 36 in the rotary mechanism 30 to lock the rods 46,47 in the extended position, but if the pawl 38 is not engaged and the turning force applied to the rotary mechanism 30 to extend the rods 46,47 (ie lock the door) is removed, the rods 46,47 are retracted under the biasing of springs 44,45.

Description

A security system for a door This invention relates to a security system for a door.

It is known to provide security systems for doors of houses.

Once such system comprises a chain, one end portion of which is secured to a door frame and the other end portion of which is provided with a slider adapted to be received in a slide located on a rear surface of a door. The arrangement is such that the door can be opened for a short distance but is restrained from opening any further by the chain.

However, the slider is adapted to be disengaged from the slide from a position behind the door so that the door can be fully opened.

A disadvantage of such a system is that it is not secure because, once the door has been opened with the chain in place, it is possible to break the chain or pull the chain away from the door frame if sufficient force is applied to the door from outside of the door.

According to the present invention, there is provided a security system for a door comprising a rotary mechanism adapted to turn on an axis and rod members extending in upward and downward directions of the door and movable in longitudinal directions of the rod members wherein the rotary mechanism is linked to the rod members so that, when the mechanism turns on the axis, an upper end portion of an upwardly extending rod member and a lower end portion of a downwardly extending rod member extend beyond corresponding upper and lower edges of the door.

The system may include upper and lower guides fixed in relation to a door frame which guides receive the respective upper and lower end portions of the rod members when they extend beyond the corresponding upper and lower edges of the door.

The system thus is more secure than door security systems known hitherto because it is only possible to open the door to the extent provided by the guides and it would not generally be possible to provide sufficient force to the door such as to move the rod members out of the corresponding guides when in engagement therewith.

Following is a description, by way of example only and with reference to the accompanying drawings of one method of carrying the invention into effect.

In the drawings: Figure 1 is a diagrammatic representation of an embodiment of a security system in accordance with the present invention, Figure 2 is a view similar to Figure 1 of another embodiment of a security system in accordance with the present invention, Figure 3 is a view similar to Figures 1 and 2 of another embodiment of a security system in accordance with the present invention, Figure 4 is a perspective view of a guide member for cooperation with a security system in accordance with the present invention, Figure 5 is an elevation of an embodiment of a tubular guide for use with a security system in accordance with the present invention, Figure 6 is an elevation of another embodiment of a tubular guide for use with a security system in accordance with the present invention, and Figures 7,8 and 9 are perspective views of corner units for mounting on a door which is also provided with a security system in accordance with the present invention.

Referring now to Figure 1 of the drawings, there is shown an embodiment of a security system in accordance with the present invention which is adapted to be secured to a door adjacent an existing door securing device. The security system 10 comprises a rectangular box 11 having upper and lower walls 12, 13 and side walls 14, 15. The box 11 also includes two internal walls 16, 17 located at diagonally opposite corners of the box 11 each extending parallel to and spaced from an adjacent side wall 14, 15. The upper and lower walls 12, 13 are provided with apertures 18, 19 intermediate a corresponding internal wall 16, 17 and adjacent side wall 14, 15. The box 11 is provided with internal posts 20, 21 located adjacent corners of the box 11 opposed to the internal walls 16,17. The posts 20, 21 have pivotally located thereon a corresponding one of two arms 22, 23 each being resiliently biased by a corresponding one of two springs 24, 25 and each arm 22,23 is provided with a guide 26, 27 and a pin 28, 29 located at an extremity of the arm 22, 23.

The box member 11 also comprises a centrally located rotary mechanism 30 for turning on a central axis 31. The mechanism 30 comprises a pair of arms 32, 33 extending in diametrically opposed directions from the axis 31 and each arm 32, 33 having at an extremity thereof a pin 34, 35. The mechanism 30 also comprises a detent 36 and a cam 37.

The box 11 also comprises a pawl 38 having a cam surface 39, the pawl 38 being pivotally located on a pin 40 and being biased by a spring 41 so that the pawl 38 is urged into the path of the detent 36.

The internal walls 16,17 and the adjacent side walls 14, 15 provide guides for a pair of sliders 42,43 having tapped recesses 44,45 each for receiving a screw threaded end portion of a corresponding one of a pair of rods 46,47 which extend through a corresponding one of the pair of apertures 18,19. Each of the sliders 42,43 is provided with a guide 48,49.

The arrangement is such that the pins 34,35 of the rotary mechanism 30 are each located in a corresponding one of guides 26,27 of the arms 22,23 and the pins 28,29 of the arms 22,23 are each located in a corresponding one of the guides 48,49 of the sliders 42,43. The springs 24,25 have the effect of biasing the corresponding arms 22,23 about the corresponding posts 20,22 towards the central axis of rotation 31 of the rotary mechanism 30. The rods 46,47 are thus moved to a retracted position, as shown in Figure 1.

When, however, the rotary mechanism is turned on the axis 31 so that the arms 32, 33 thereof turn the pivotally mounted arms 22, 23 causing the sliders 42, 43 to move towards adjacent upper and lower walls 12, 13 of the box 11 against the bias of the springs 24, 25, the rods 46, 47 respectively move upwardly and downwardly relative to the box 11.

The rods 46,47 are of such dimension that, when the box 11 is located on a rear surface of a door, remote end portions of the rods 46,47 are located inwardly within a perimeter of the door when the rods 46,47 are in the retracted position shown in Figure 1, but, when in an extended position in which the sliders 42,43 are adjacent a corresponding upper or lower wall 12,13 of the box 11, the remote end portions of the rods 46,47 extend beyond corresponding upper and lower edges of the door.

Preferably, the upper and lower edges of the rods 46,47 are screw threaded, as shown at 48,49, and are received in tapped recessed of cylindrical end caps 50,51 each of which is slidably received a corresponding one of a pair of tubular guides 52,53 mounted at corresponding locations adjacent the upper and lower edges of the door.

The end caps 50,51, when the rods 46,47 are in an extended position, locate in a corresponding one of a pair of arcuate guides, one of which is shown at 54 in Figure 4, located in a fixed position relative to a door post (not shown).

In use, the rotary mechanism 30 is turned on the axis 31 so that the arms 22,23 pivot relative to the posts 20,21 and move the rods 46,47 from their retracted position shown in Figure 1 to the extended position in which the end caps 50,51 are received in the corresponding guides 54. As the rods 46,47 approach the extended position, the pawl 38 engages the detent 36 thereby restraining reverse movement of the rotary mechanism 30 relative to the axis 31, due to the bias of the springs 24,25 when the turning force on the rotary mechanism 30 is released. The extent to which the door is openable, therefore, is determined by the arcuate dimension of the guides 54, which dimension would be a distance comparable with the extent to which a door having a chain security mechanism in place could be opened.

When it is necessary to release the rods 46,47, the rotary mechanism 30 is turned in an opposite direction from outside of the door about the axis 31, ie in an anti-clockwise direction in Figure 1, as a result of which the cam 37 of the rotary mechanism 30 engages the cam surface 39 of the pawl 38 causing the pawl 38 to pivot on the pin 40 away from the axis of rotation 31 of the rotary mechanism 30 thereby effecting disengagement of the pawl 38 with the detent 36.

In consequence, the arms 22,23 are biased by the springs 24,25 about their posts 20,21 thus returning the components to the position shown in Figure 1.

Referring now to Figure 2 of the drawings, there is shown a security system 55 which is similar to the security system 10, except that it is turned through 180 degrees, and corresponding components are provided with the same reference numerals. In the security system 55, however, the arm 22 and corresponding post 20 and spring 24 are moved closer to the internal wall 17 thereby to provide room for a third rod 56 and corresponding slider 57. A third internal wall 58 is provided to form, with the side wall 14, a guide for the slider 57, which slider 57 also includes a guide 59.

The rotary mechanism 30 is provided with a third arm 60 having at a location thereof remote from the axis 31 a pin 61 which is located in the guide 59 of the slider 57. The wall 13 is provided with a second aperture 62 for locating the rod 56.

The system 55 thus provides additional security of the third rod 56.

Referring now to Figure 3 of the drawings, there is shown a security system 63 which is similar to the system 55 except that the rod 47 and accompanying slider 43, and the associated arm 22 have been removed and replaced by an elongate slidable catch 64 having an elongate slot 65, in which is located the post 20, and having a notch 66 in which is located the pin 34 of the arm 22 and having an end wall 67 provided with an abutment surface 68. The side wall 14 is provided with an aperture 69 through which projects a striker surface 70 of the catch 64 and the catch 64 is resiliently biased by means of springs 71 engaging with the internal wall 17 so that the catch 64 is urged in a direction away from the wall 17.

The rotary mechanism 30 includes a coaxial shaft 72 having a radial projection 73, the shaft 72 being turnable on the axis 31 independently of the rotary mechanism 30.

The arrangement is such that a door carrying the security system 63 may be opened without operating the rods 46,56 by turning the coaxial shaft 72 relative to the rotary mechanism 30 thereby causing the catch 64 to move towards the wall 17 due to the radial projection 73 moving in an arcuate direction relative of the axis 31 and engaging the abutment surface 68 of the end wall 67 of the catch 64 and effecting longitudinal movement of the catch 64 relative to the post 20. When the turning force causing the arcuate movement of the projection 73 is released, the mechanism returns to the position shown in Figure 3 due to the bias of the springs 71.

In another embodiment of the invention (not shown) the catch 64 is located to the left of the pin 34 in the configuration shown in Figure 3 such that, when the door is closed and the catch 64 moves towards the wall 17 on striking a strike plate, the end wall 67 engages the pin 34 causing rotation of the rotary mechanism 30 so that the rods 46,56 move to operative positions and are maintained in those positions by the pawl 38 engaging the detent 36 until released by turning the rotary mechanism 30 in an opposite direction as described above. The operation of turning the rotary mechanism 30 in the opposite direction is effected by inserting a key into the mechanism 30 from outside of the door.

Referring to Figure 5 of the drawings, there is shown an elevation of one of the tubular guides 52 which is located on a corner bracket 74 adapted to be secured to two adjacent surfaces of a door which surfaces extend at 90 degrees one to another. The other tubular guide 53 would be similarly formed. However, it will be appreciated that a mechanism in accordance with the present invention may be located within a door. With such an arrangement, each tubular guide 52; 53 may be formed integrally with a corresponding one of a pair of corner units, one of which is shown at 75 in Figure 6, whereby, when mounted on a door, the tubular guide 52 locates within a perimeter of the door.

Referring now to Figure 7 of the drawings, there is shown a corner unit 76 for attaching to a corner of a door which is also provided with a security system in accordance with the present invention. The corner unit 76 is not provided with a tubular guide 52 and is purely for decorative purposes so as to provide a corner of the door remote from the security system with a decorative component which aesthetically complements a corresponding component located at an opposite corner of the door and which component carries a tubular guide 52. The corner unit 76 comprises a front plate 77 of arcuate configuration, corresponding in configuration with a front plate of the corner unit 75, and two elongate rectangular face plates 78,79 extending in planes at right angles one to another and at right angles to the plane of the front plate 77.

An alternative corner unit 80 is shown in Figure 8 which is similar to the corner unit 76 except that the corner unit 80 includes a triangular front plate 81. A further alternative corner unit 82 is shown in Figure 9 and comprises a rectangular plate 83 which is secured to a corner of a door (not shown) by three screws 84,85 and 86.

Claims

1. A security system for a door comprising a rotary mechanism adapted to turn on an axis and rod members extending in upward and downward directions of the door and movable in longitudinal directions of the rod members wherein the rotary mechanism is linked to the rod members so that, when the mechanism turns on the axis, an upper end portion of an upwardly extending rod member and a lower end portion of a downwardly extending rod member extend beyond corresponding upper and lower edges of the door.

2. As system as claimed in Claim 1 wherein there is provided resilient means or returning the rod members to retracted positions when a turning force applied to the rotary mechanism is released.

3. A system as claimed in Claim 2 wherein there is provided restraining means fo restraining movement of the rod members to the retracted positions when the turning force applied to the rotary mechanism is released.

4. A system as claimed in Claim 3 wherein there is provided release means for releasing the restraining means.

5. A system as claimed in Claim 4 wherein the restraining means comprises a detent carried on the rotary mechanism.

6. A system as claimed in Claim 5 wherein the restraining means further includes a pawl adapted to engage the detent.

7. A system as claimed in Claim 6 wherein the release means comprises a cam operable by the rotary means and a cam surface carried by the pawl, the cam surface being adapted to be engaged by the cam so as to move the pawl away from the detent.

8. A system as claimed in any one of Claims 3 to 7 wherein the turning force applied to the rotary mechanism is effected by operation of a slidable catch.

9. A security system for a door substantially as hereinbefore described and as illustrated in Figure 1 or Figure 2 or Figure 3 of the accompanying drawings.