GB2272246A

GB2272246A - Security door or shutter latching mechanisms

Info

Publication number: GB2272246A
Application number: GB9223159A
Authority: GB
Inventors: Peter Charles Remnant
Original assignee: STEELSPACE LYDNEY Ltd
Current assignee: STEELSPACE LYDNEY Ltd
Priority date: 1992-11-05
Filing date: 1992-11-05
Publication date: 1994-05-11
Anticipated expiration: 2012-11-05
Also published as: GB9223159D0; GB2272246B

Abstract

A latching mechanism comprises a male member 8 for mounting on the inside of the door or shutter 1, 2, and a female member 9 for mounting on a fixed frame 3 and adapted to receive the male member 8 therein when the male member is moved inwardly towards the frame as the door or shutter is closed. A catch element 12 is engageable in a recess 25 to retain the male member within the female member holding the door or shutter closed. Furthermore a catch release 13 is actuable from inside the frame 3 to release the catch element 12 from the recess 25 so as to permit the opening of the door or shutter. The catch element 12 automatically locks the male member 8 within the female member 9 when the door or shutter is closed, thus enabling the door or shutter to be locked from the outside, whilst the catch release 13 on the inside of the frame may subsequently be used to release the door or shutter. <IMAGE>

Description

"Security Door or Shutter Latchina Mechanisms" This invention relates to security door or shutter latching mechanisms and is concerned more particularly, but not exclusively, with shutter latching mechanisms for security site cabins.

Temporary cabins are commonly installed on construction sites for providing on-site offices and other accommodation for personnel. Such cabins are conventionally of prefabricated construction based on wood or wood-based materials. However, particularly where the construction site is at a remote location, such cabins are prone to be broken into or vandalised. Theft and vandalism on construction sites is an increasing problem, and accordingly there is a need for such cabins to be made as secure as possible. It has already been proposed to base the construction of such cabins on that of steel site storage containers but with windows being provided in the sides of the containers so as to make them of generally similar form to conventional cabins.

As well as being provided with a securely lockable door, such cabins are provided with conventional windows over which steel shutters are fitted which may be securely locked from the inside when the cabin is not in use. However existing locking mechanisms for such shutters are cumbersome to operate. Closing of the shutters requires a substantial degree of strength, and, after the shutters have been closed from the outside of the cabin, they must then be locked from the inside, so that it is not possible for the shutters to be locked after the door has been locked.

It is an object of the invention to provide a novel shutter latching mechanism which is considerably more convenient to use.

According to the present invention, there is provided a security door or shutter latching mechanism comprising a male member for mounting on the inside of the door or shutter to be latched so as to project inwardly of the door or shutter, a female member for mounting on a fixed frame in relation to which the door or shutter is to be latched and adapted to receive the male member therein when the male member is moved inwardly towards the frame as the door or shutter is closed, a catch element extending through a slot in a wall of the female member and engageable in a recess in the male member when the male member is received within the female member to retain the male member within the female member, and a catch release actuable from inside the frame to release the catch element from the recess in the male member so as to permit the male member to be moved outwardly of the female member to open the door or shutter.

The catch element will automatically lock the male member within the female member when the door or shutter is closed, thus enabling the door or shutter to be locked from the outside, whilst the catch release provided on the inside of the frame may subsequently be used to release the door or shutter. Thus the latching mechanism is both convenient in use and does not require any particular degree of strength on the part of the operator.

The male member is conveniently a projecting pin having a peripheral groove constituting said recess adjacent to its tip.

The female member is conveniently a tubular sleeve having a lateral slot for the catch element extending through its wall over part of its periphery.

The spring-biased catch element is preferably a torsion spring having an end leg which extends through the slot in the wall of the female member. In this case the catch release may be in the form of a flexible elongate member connected to the end leg of the torsion spring.

Furthermore the mechanism preferably also includes a spring-biased ejector element which is loaded when the male member is retained within the female member by the catch element and which serves to eject the male member from the female member when the catch element is released from the recess in the male member.

The spring-biased ejector element is preferably a compression spring in which case the compression spring is advantageously mounted on the male member so as to be compressed by a washer on the male member when the male member enters the female member.

When the latching mechanism is installed in the security container or cabin with the male member mounted on the door or shutter and the female member mounted on the frame, it is convenient for the female member to extend through the frame so as to project from the inside of the frame and for the catch element and catch release to be located on the inside of the frame.

In a preferred embodiment two latching mechanisms are installed with their male members mounted at the top and bottom of the door or shutter and their female members mounted at corresponding positions on the frame, and a common catch release in the form of a flexible elongate member is connected between the catch elements of the two mechanisms so as to be actuable to effect simultaneous release of the two catch elements.

where the latching mechanism is used on a pair of window shutters, the male member of the latching mechanism may be mounted on one of the shutters, and a part of said one shutter may be arranged to overlay a part of the other shutter when the shutters are closed so that the latching mechanism serves to secure both shutters simultaneously.

In order that the invention may be more fully understood, a latching mechanism according to the invention for the window shutters of a site cabin will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows the window frame and associated shutters from above; Figure 2 is an inside view of the window frame; Figure 3 is a side view of a detail of the latching mechanism in the closed position; and Figure 4 is a detail of the inside of the window frame showing the catch element of the latching mechanism.

Referring to Figure 1 two shutters 1 and 2 are pivotally connected to a window frame 3 by hinges 4. The frame 3 has a surrounding side flange 5 which lies closely adjacent the corresponding sides of the shutters 1 and 2 when the shutters are closed so as to prevent the introduction of a tool between the frame and the shutters to force the shutters open. Two latching mechanisms 6 and 7 are mounted at the top and bottom of the shutter 1 (as will be appreciated from Figure 2) and each comprises a projecting pin 8 mounted on the shutter 1 and a tubular sleeve 9 extending through the corresponding part of the frame 3 so as to project from the inside of the frame.

The shutter 1 also has a vertical channel member 10 welded to its free edge and providing flanges 11 arranged to overlay the free edge of the shutter 2 so that, when the shutters are closed, the two latching mechanisms 6 and 7 serve to secure both shutters simultaneously.

Referring to Figure 2, each latching mechanism 6 or 7 is provided with a spring-biased catch element 12 in the form of a torsion spring which serves to retain the pin 8 within the sleeve 9 when the shutters are closed and which will be described in more detail below. Furthermore a common catch release wire or cord 13 is connected between the catch elements 12 of the two latching mechanisms 6 and 7 so as to be capable of effecting simultaneous release of the two catch elements when the wire or cord 13 is pulled in the direction of either of the arrows 14 and 15.

Figure 3 shows the pin 8 within the sleeve 9 of the latching mechanism 7 at the bottom of the shutter 1 when the shutters are closed. The pin 8 extends through an aperture in the shutter 1 and is secured therein by a nut 16 over which a cover plate 17 is welded to make it captive. The sleeve 9 extends through the angle-section bottom member 3A of the frame 3 so as to project inwardly of the frame. An ejector spring 18 is provided on the pin 8 between the inside of the shutter 1 and a washer 19 which is retained on the pin 8 but which is capable of being forced inwardly to compress the spring 18 when the pin 8 is received within the sleeve 9 on closing of the shutters.

Referring to Figures 3 and 4, the catch element 12 is in the form of a torsion spring fixed to the inside of the frame 3 by a bolt 20 and having a first end leg 21 bearing against the wall of the sleeve 9 on one side and a second end leg 22 extending through a slot 23 in the wall of the sleeve 9 on the other side. The pin 8 has a pointed tip 24 such that, when the pin 8 initially enters the sleeve 9 and the tip 24 contacts the leg 22 of the catch element 12, the leg 22 is initially forced outwardly against the spring bias and is then caused by the spring bias to snap into an annular groove 25 provided on the pin 8 behind the tip 24. In this final position, shown in Figure 3, the pin 8 is securely locked within the sleeve 9.

When the catch element 12 is subsequently released from the groove 25 by pulling on the catch release wire 13 which is secured to an extension part 26 of the leg 22, the spring force due to previous compression of the ejector spring 18 on the pin 8 will immediately cause the pin 8 to be ejected from the sleeve 9 and will thus automatically cause release of the shutters.

It will be appreciated that window shutters fitted with such latching mechanisms may be locked simply by closing the shutters from the outside, and, when locked, provide a high degree of security against forcing or tampering. Furthermore release of the shutters can be achieved in straightforward manner simply by pulling a release wire on the inside of the window frame.

Claims

1. A security door or shutter latching mechanism comprising a male member for mounting on the inside of the door or shutter to be latched so as to project inwardly of the door or shutter, a female member for mounting on a fixed frame in relation to which the door or shutter is to be latched and adapted to receive the male member therein when the male member is moved inwardly towards the frame as the door or shutter is closed, a catch element extending through a slot in a wall of the female member and engageable in a recess in the male member when the male member is received within the female member to retain the male member within the female member, and a catch release actuable from inside the frame to release the catch element from the recess in the male member so as to permit the male member to be moved outwardly of the female member to open the door or shutter.

2. A latching mechanism according to claim 1, wherein the male member is a projecting pin having a peripheral groove constituting said recess adjacent to its tip.

3. A latching mechanism according to claim 1 or 2, wherein the female member is a tubular sleeve having a lateral slot for the catch element extending through its wall over part of its periphery.

A A latching mechanism according to claim 3, wherein the catch element is a torsion spring having an end leg which extends through the slot in the wall of the female member.

5. A latching mechanism according to claim 4, wherein the catch release is in the form of a flexible elongate member connected to the end leg of the torsion spring.

6. A latching mechanism according to any preceding claim, which also includes a spring-biased ejector element which is loaded when the male member is retained within the female member by the catch element and which serves to eject the male member from the female member when the catch element is released from the recess in the male member.

7. A latching mechanism according to claim 6, wherein the spring-biased ejector element is a compression spring mounted on the male member so as to be compressed by a washer on the male member when the male member enters the female member.

8. A security door or shutter latching mechanism substantially as hereinbefore described with reference to the accompanying drawings.

9. A security container or cabin incorporating a latching mechanism according to any preceding claim, wherein the male member is mounted on a door or shutter of the container or cabin, the female member is mounted on a frame of the container or cabin and extends through the frame so as to project from the inside of the frame, and the catch element and catch release are located on the inside of the frame.

10. A security container or cabin according to claim 9, wherein two latching mechanisms are installed with their male members mounted at the top and bottom of the door or shutter and their female members mounted at corresponding positions on the frame, and a common catch release in the form of a flexible elongate member is connected between the catch elements of the two latching mechanisms so as to be actuable to effect simultaneous release of the two catch elements.

11. A security container or cabin according to claim 9 or 10, in which the or each latching mechanism is used to latch a pair of window shutters, wherein the male member of the or each latching mechanism is mounted on one of the shutters, and a part of said one shutter is arranged to overlay a part of the other shutter when the shutters are closed so that the or each latching mechanism serves to secure both shutters simultaneously.

12. A security container or cabin substantially as hereinbefore described with reference to the accompanying drawings.