A locking device

Abstract: A locking device 1 comprising a link 9, a portion of which is adapted to pass through an opening 50 of a keep 52, during use, and a bolt 5, wherein the bolt 5 is moveable between a first position in which it is inactive (figures 2 and 4) and a second position in which it blocks the opening 50 to prevent retraction of the link 9 from the keep 52 (figures 1 and 5). Such a locking device is particularly suitable for use in a sliding patio door system, since it provides a very firm lock and ensures that the sliding patio door cannot be forced open.

Description: This invention relates to locking devices, and in particular to a locking device for use with a sliding patio door system. Many forms of locking device are known, such as deadlocks, spring-loaded locks, bolts, etc. Such devices are perfectly adequate when used in conjunction with hinged doors and door frames. However, other forms of locking device must be utilised if the door, or other vent, is of the sliding kind, such as a sliding patio door. It is known to lock a sliding patio door by engaging a hook, mounted on the door and activated by a handle, over a bar mounted in the stationary support frame. The hook and handle are then locked in position by means of any suitable locking device, such as a deadlock engaging the handle. Unfortunately, it has been shown that it can be possible to overcome such a locking device by simply raising the whole patio door so that the hook disengages from the bar, thereby allowing the door to be opened. It is also known to use a series of mushroom pins arranged along the leading edge of a sliding patio door. As the door is closed fully, the pins enter openings in a channel mounted on the stationary door frame. A handle on the sliding door is then turned to raise or lower the pins, such that they pass behind flanges formed on the channel in the frame. In this way, the patio door is prevented from sliding open until the mushroom pins are moved back to their initial positions opposite the openings in the channel. Once again, however, it is possible to force open such a patio door. This can be achieved, for example, by inserting a flat heavy object, such as a spade, between the sliding door and the support frame, thereby opening up the channel or simply breaking the mushroom pins, which have relatively weak necks. In the light of the foregoing, it will be appreciated that there is a distinct need for a locking device which is suitable for use with a patio door system, and which, when in its active position, provides a very strong lock between the patio door and its stationary support frame. The present invention aims to satisfy this need, but is also readily usable in many other applications. According to the present invention, there is provided a locking device comprising a link, a portion of which is adapted to pass through an opening of a keep, during use, and a bolt, wherein the bolt is moveable between a first position in which it is inactive and a second position in which it enters the opening to prevent retraction of the link from the keep. Preferably the locking device comprises a drive means for moving the bolt between its first position and its second position. The drive means may take many different forms, but preferably includes a drive rod for attachment to a handle. The link may include a flattened region which abuts a wall of the opening when the bolt is in its second position, during use. Alternatively, the link may simply include an enlarged end portion which is able to pass through the opening, but which cannot pass back through the opening when the bolt is in its active, second position. In a preferred embodiment of the invention, the link is shaped from a flat sheet of metal. If this is the case, an end region of the link is bent to provide an enlarged effective area for preventing retraction of the link when the bolt is in its second position. The bolt is preferably substantially planar and moves in a plane substantially parallel to the plane of the link. As will be appreciated, a locking device according to the present invention is preferably utilised in a sliding vent. However, it is possible for the locking device to be mounted in a support frame and for a keep to be mounted on a sliding vent for mating therewith. If the locking device is mounted on a sliding vent, the vent preferably slides along a track within a support frame such that, when closed, the link of the locking device penetrates a keep mounted on a substantially vertical portion of the frame. The locking device may be mounted within a hollow portion of the vent adjacent an aperture through which only the link and bolt extend. Such a mounting of the locking device ensures that the locking device cannot be readily broken away from the sliding vent itself. In a preferred embodiment of the invention, there is provided means to prevent the bolt moving to its active second position until the link has penetrated the keep. The prevention means may include a spring-biased protrusion which cooperates with a bearing plate only when the vent is closed. It is also preferable that, as the bolt enters the opening in the keep to lock the vent, a swing bolt engages a second keep in a horizontal part of the support frame. If such a swing bolt is included, additional locking strength is provided. As will be appreciated, a sliding vent will preferably include a plurality of locking devices according to the present invention. If many locking devices are utilised, a single handle preferably actuates them all at the same time. More preferably, a lock and key are included to enable the handle to be locked when the bolt or bolts are in the active position. A particularly preferred use of a locking device according to the present invention is in a sliding patio door system. Other uses can of course be envisaged. Finally, each keep defines an opening having two sides, a top and a bottom, and includes grooves for engaging flanges of a channel in a support frame of a vent. During assembly, the grooves in the or each keep preferably engage the flanges of the channel, thereby preventing the or each keep from being pulled away from the support frame. Furthermore, by being in sliding engagement with the support frame. The positions of the keep can be readily adjusted as necessary during installation. A specific embodiment of the present invention is now described, by way of example only, with reference to the accompanying drawings, in which:- Figure 1 is a side view of a locking device in its active position, partially cut-away, and with its shaped link removed for clarity; Figure 2 is a side view as shown in figure 1, but with the bolt in its inactive position (the active position of the bolt is shown in chain line); Figure 3 is a rear view of the locking device shown in figures 1 and 2; Figure 4 is a view in the direction A-A of figure 2, but with the shaped link included; Figure 5 is a partial view corresponding to figure 4, but with the locking device in its active position as shown in figure 1; Figure 6 shows the parts of the locking device, excluding the shaped link and screws, separated for clarity; and Figure 7 is a schematic representation of a sliding patio door system including four locking devices according to the present invention. With reference to the drawings, a locking device 1 according to the present invention includes a shoot bolt case 2, a drive rod 3, a shoot bolt 5, a shoot bolt cover 7 and a shaped link 9. The shoot bolt case 2 includes a deep channel 11 for receiving the drive rod 3 in sliding relation thereto. The shoot bolt case 2 further includes a recessed portion 13 for receiving the shoot bolt 5. The shoot bolt 5 includes an arm 5a having a nose portion 5b which engages in a recessed track 15 in the shoot bolt case 2. The recessed track 15 is perpendicular to the deep channel 11. The drive rod 3 includes a pin 17 mounted thereon for engagement with a corresponding aperture 19 in the shoot bolt 5. Due to this arrangement, as the drive rod 3 moves up or down along the deep channel 11, the pin 17 forces the shoot bolt 5 between its active (figure 1) and inactive (figure 2) positions. The nose portion 5b of the shoot bolt 5 helps to ensure smooth movement of the shoot bolt 5 perpendicular to the drive rod 3. The shoot bolt cover 7 is fixed via screws 21 to the shoot bolt case 2, thereby holding the drive rod 3 and shoot bolt 5 in position. The shoot bolt cover 7 also includes two flanges 23 extending substantially perpendicularly to its main plane. These flanges dictate the position of the shaped link 9 by ensuring that the link 9 always extends over the edge of the shoot bolt case 2 (as shown in figures 4 and 5), irrespective of whether the shoot bolt 5 is in its active or inactive position. With specific reference to figure 7, a sliding patio door system 30 includes a fixed door 32 and a sliding door 34. Each door 32,34 includes a large pane of glass or double glazing. The sliding door 34 runs in a track 36 which engages both the top and bottom of the door 34. As shown, the sliding door includes four locking devices 1 according to the present invention. The four locking devices 1 are all activated by means of a single drive rod 3 which is driven by a handle 38. When the handle 38 is in its locking position, it can be prevented from turning if a dead-lock 40 is activated by a key (not shown). Such a handle 38 and dead-lock 40 mechanism is well known in the art. The handle 38 can only be turned into its locking position when a spring-loaded release catch engages a bearing plate 42 on the track 36. Hence, the patio door can only be locked when it is in its fully closed position. Further, when the handle 38 is turned into its locking position, it drives the drive rod 3 upwards and this urges a swing-bolt 44 into a recess in the bearing plate 42. In this way, additional locking of the patio door is effected. The four locking devices 1, according to the present invention, are positioned within a hollow portion of the vertical frame 46 of the sliding door 34. The devices 1 are held in position by means of screws (not shown) passing through a metal skin of the vertical frame 46 and engaging threaded holes 48 (c.f. figure 3) in the shoot bolt case 2. The hollow vertical frame 46 also includes apertures adjacent the locking devices 1 through which the shoot bolts 5 and shaped links 9 extend. Due to the size of these apertures and the flanges 23 of the shoot bolt covers 7, the shaped links 9 are held in position. In use, as the patio door 34 slides closed and the shaped links 9 pass through apertures 50 in keeps 52, the shoot bolts 5 are all in their inactive positions (c.f. figure 2). This is because the handle 38 has not been allowed to move into its locked position, as described above. However, when the door is fully closed, the handle 38 can be swung into its locked position, thereby driving the drive rod 3 upwards. The drive rod 3, via its pins 17, urges each shoot bolt 5 into its active position (c.f. figure 1) and through the aperture 50 in its respective keep 52 mounted on the stationary support frame 54 of the patio door system. As can be seen from figures 4 and 5, the position of the shaped links 9 is altered slightly as the shoot bolts 5 engage the apertures 50. As this occurs, the links 9 abut the edge of the apertures 50 and, due to the shaped ends of the links 9, cannot be retracted from the apertures 50 because the shoot bolts 5 are filling the remaining space. Hence, the patio door 34 cannot be opened until these locking devices are once again released, which is a simple reverse of the locking procedure. Although four locking devices 1 have been shown incorporated in the patio door system of figure 7, more or less locking devices 1 could equally well be used. Furthermore, although the shaped links 9 are shown manufactured from flat sheets of metal, other shapes or materials could also be used. It will of course be understood that the present invention has been described above purely by way of example, and that modifications in detail can be made within the scope of the invention as claimed.

Claims: A locking device (1) comprising a link (9), a portion of which is adapted to pass through an opening (50) of a keep (52), during use, and a bolt (5), wherein the bolt is moveable between a first position in which it is inactive and a second position in which it enters the opening (50) to prevent retraction of the link (9) from the keep (52). A locking device as claimed in claim 1, further comprising a drive means for moving the bolt (5) between the first position and the second position. A locking device as claimed in claim 2, wherein the drive means includes a drive rod (3) for attachment to a handle (38). A locking device as claimed in any preceding claim, wherein the link (9) includes a flattened region which abuts a wall of the opening (50) when the bolt (5) is in its second position, during use. A locking device as claimed in any preceding claim, wherein the link (9) is shaped from a flat sheet of metal. A locking device as claimed in any preceding claim, wherein the bolt (5) is substantially planar and moves in a plane substantially parallel to the plane of the link (9). A sliding vent (32,34) including a locking device (1) as claimed in any preceding claim. A vent as claimed in claim 7, which slides along a track (36) within a frame (54) such that, when closed, the link (9) penetrates a keep (52) mounted on a substantially vertical portion of the frame (54). A vent as claimed in claim 7 or claim 8, wherein the locking device (1) is mounted within a hollow part of the vent frame adjacent an aperture in the frame through which the bolt (5) and link (9) extend. A vent as claimed in any one of claims 7-9, wherein means is provided to prevent the bolt (5) moving to its active second position until the link (9) has penetrated a keep (52). A vent as claimed in claim 10, wherein the prevention means includes a spring-biased protrusion which cooperates with a bearing plate (42) only when the vent (32,34) is closed. A vent as claimed in any one of claims 7-11, wherein as the bolt (5) enters the opening (50) in the keep (52) to lock the vent (32,34), during use, a swing bolt (44) engages a keep (42) in a horizontal part of a support frame. A vent as claimed in any one of claims 7-12, wherein a plurality of locking devices (1) are provided, all activated by single handle (38). A vent as claimed in claim 13, wherein a lock (40) is provided for locking the handle (38) when the bolts (5) are in their active second position. A vent as claimed in any one of claims 7-14, wherein the vent (32,34) is a patio door.

Inventors: TAYLOR ANDREW MARTIN, TAYLOR, ANDREW MARTIN
Applicants: SECURISTYLE LTD, SECURISTYLE LIMITED
Application year: 1992
Main classification: E05B65
IPC codes: E05B65, E05C9