AUTOMATIC TWO POSITION LOCKING DEVICE FOR WINDOWS

Abstract: A latching device for locking an openable frame (14) relative to a fixed frame (12) of a glazed panel assembly (10) in either of a fully closed position or an ajar position, comprises a fixed latch (16) carried by the one of the frames which passes through an opening (32) in the other of the frames and engages a displaceable keeper (48) carried by the other frame. The keeper engages the latch in either of two positions automatically as the openable frame is moved in a closing direction.

Description: AUTOMATIC TWO POSITION LOCKING DEVICE FOR WINDOWS - 1 - TECHNICAL FIELD This invention relates to a secur ity latching device for locking an openable frame relative to a fixed frame of a. * glazed panel assembly, preferably in either of .a fully closed position or an ajar position , locking being achieved in either case automatically consequent upon closing movement of the openable frame. The invention is particularly useful for provid ing a secur ity lock for windows in which a glazed open able frame automa ically can be locked in fully closed position simply by closing the openable frame, or alternatively, in a so-called night venting position in which the openable frame is locked relative to the fixed frame in an aj ar position . BACKGROUND ART A security device for latching a window shutter is disclosed in GB-2 080 377 in which a fixed catch carried by the shutter engages a spring loaded latch secured in a wall cavity adjacent the window to lock the shutter. Once the shutter has been closed it can be released only by means of a knob located inside the building. However, this security device requires the wall of the building to be bored through to accommodate the release means and also is susceptible to tampering from outside the building. Furthermore, this security device is not concerned with locking an openable window frame. DISCLOSURE OF THE INVENTION The present invention is concerned with a security latching device which automatically locks together and openable window frame and a fixed window frame and has the advantage that the whole device is carried by the frames themselves, and can be installed in a new building o ~ a-s part of a replacable window assembly without modification to the building itself. Moreover, when in its locked position, the locking engagement is internal of the building and is inaccessible to tampering from outside the buil ing. To this end, one aspect of the invention provides in a g aze 1 panel assembly comprising a fixed frame and an openable frame an automatic latching device for locking the openable frame to the fixed frame automatically consequent upon closing movement of the openable frame relative to the fixed frame, said device comprising a fixed latch carried by one of said fixed or openable frames, an opening in the other of said fixed or openable frames through which the fixed latch extends to lock the frames together, displacable locking means provided by the other of said fixed or openable frames disposed adjacent said opening and remote from said one frame operable automatically to engage the fixed latch as the openable frame is moved to a closed position relative to the fixed frame, and release means for disengaging the locking means and the fixed latch. Preferably, the fixed latch is adapted to engage the displacable locking means in either of two different locations and thereby to lock the openable frame relative to- the fixed frame in a closed position or in at least one- ajar position. In some constructions, the fixed latch is carried by the fixed frame and the displacable locking means is provided by the openable frame whereas in other constructions the fixed latch is carried by the openable frame and the displacable locking means is provided by the fixed frame. Normally, in a so-called " ilt- n -turn" window assembly, it is envisaged that the fixed latch would be carried by the fixed frame of the assembly and in the locking mode, pass through an opening in the openable frame for locking engagement with the displacable locking means. Conversely in a casement window, it is envisaged that the fixed latch would be carried by the openable frame of the assembly and, in the locking mode, pass through an opening in the _> fixed frame for locking engagement with the displacable locking means. - The fixed latch may include a lead ing cam surface for displac ing the displacable locking means and a leading locking recess into which a locking edge of the displacable means engages to lock the fixed latch and the displacable locking means together, the d isplacable locking means, comprising a keeper plate including _ an aperture defining the locking edge, the keeper plate being resiliently sl idable with respect to said other of the frames from a locked position in which the aperture is partially out of register with said frame open ing so " that the locking edge is located in the leading locking recess to a released position in which the aperture substantially is in register with the frame opening so that the locking edge is clear of the leading locking recess. In constructions where these features are adopted, the fixed latch may include a trailing cam surface aligned with said leading cam surface and forming an edge of said leading locking recess and a trailing locking recess spaced from said leading locking recess whereby the locking edge of keeper plate can be caused to ride over both said cam surfaces and engage in the trailing locking recess thereby to lock the openable frame in an ajar position relative to the fixed frame. Preferably, the keeper plate is disposed in superposed relationship with respect to a guide plate by which the slidable plate is held for sliding movement relative thereto, the guide plate having a slot in registry with the frame opening sized to receive said fixed latch. Tili . disengaging means may comprise a portion of the keeper" plate accessible for manipulation to bring the locking edge into and out of engagement with the or each locking recess provided by the fixed latch. Another aspect of the invention provides a latching device one for a glazed panel assembly comprising a fixed frame and an openable frame, which device comprises a fixed latch on the openable frame, an opening in the fixed frame through which a portion of the fixed latch extends when the openable frame is moved to approach a closed position and displacable locking means provided by the fixed frame automatically to engage the fixed latch in either of two different locations thereby to lock the openable frame relative to the fixed frame in a closed position or in an ajar position, and release means for disengaging the locking means and the fixed latch. Yet another aspect of the invention provides in a glazed panel assembly comprising a fixed frame and an openable frame, an automatic latching device for locking the openable frame to the fixed frame in a closed position or in an ajar position, locking of the frame together being effected in said closed position or said ajar position automatically consequent upon closing movement of the openable frame_relative to the fixed frame. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described , by way of example, with reference to the accompanying drawings , in which : - FIGURE 1 is a sectional plan view of a part of a glazed panel assembly incorporating a latching device according to the invention in which the openable frame is in an open position with the latching device unlocked; FIGURE 2 is a view similar to Figure 1 but in which the openable frame is in a closed po sition with the latching device locked; FIGURE 3 is a part-sectional perspective view of a preferred version of a latching device according to the invention; and FIGURE 4 is a part- sectional side view of the latching device shown- in " Figure 3 . ^ BEST MODE FOR CARRYING OUT THE INVENTION Referring to the drawings, a glazed panel assembly 10 providing a window comprises a fixed frame 12 and an 5. openable frame 14 which is glazed and hinged to the fixed frame so that it can be pivoted relative thereto from a closed position to an open position and also to an intermediate ajar position. In either of the first or latter positions, the openable frame is locked to the 10 fixed frame. The openable frame 14 carries a fixed latch 16 of the latching device and the fixed frame 12 is provided with the remaining components (the keeper assembly) of the latching device. 1'5 " The fixed latch 16 is in the form of a steel 'T' -shaped plate which may be straight or cranked intermediate its ends depending on the frame configuration to which it is mounted. The head of the 'T' latch is secured to an outer side edge face 14a of the openable frame by suitable 20 fasteners 18 so that the free leading end portion of the stem of the 'T l projects proud of the frame periperhy towards the fixed frame. Adjacent the free end portion of the stem, its upper edge is formed with two locking recesses 20 and 22 spaced apart by a tooth 24 which has a 25 backwardly raked cam surface 24a. Likewise, the tip of the stem is formed with a leading tooth 26 with a backwardly raked cam surface 26a. Thus, the leading locking recess 20 is generally 'V'-shaped as seen in the side view of Figure 4 being defined partly by cam surface 24a whereas the trailing locking recess 22 is 'U'-shaped. The keeper assembly comprises an elongate guide plate 28 which is adapted to be secured onto a face 12b of the fixed frame remote from the latch i.e. the perimeter face of the fixed frame which is intended to be internal of a building. The guide plate is formed with a longitidinal slot 30 appropriately positioned so that when the guide plate is secured to the fixed frame, slot 30 is in registry with a slotted opening 32 in the fixed frame 12. Opening 32 is positioned to receive latch 16 when the openable frame is closed or ajar. Guide plate 28 includes overturned elongate side flanges which form spaced guide channels 34 and 36 respectively. The guide plate is drilled at upper and lower locations only, the lower 38 of which is shown in Figure 13 to receive fasteners e.g. 40 by which the guide plate is secured to the -fixedr frame. A cover 42 is a snap fit onto the periphery of the guide plate. The guide plate receives a displacable keeper plate 48 whose opposite side edges 50 and 52 are received in the guide channels 34 and 36 respectively whereby the keeper plate can slide longitudinally in opposed directions 5; relative to the guide plate. The keeper plate includes a slotted elongate portion 'p' which normally extends beyond one end of the guide plate and passes through an opening 54 formed in an end wall 56 of the cover 42. The slot ' s' allows the keeper plate to move relative to the fastener 10 40. The elongate portion terminates in an upturned lip 60 by which the keeper plate can be manipulated. The keeper plate moves relative to the guide plate from a locked position (shown in Figures 2 and 4) in which lip 60 ' is remote from end wall 56 of the cover 42 to a release 1.5, position in which the lip 60 is adjacent end wall 56. The keeper plate is formed with a slot 62 which is in registry with slot 30 of the guide plate and opening 32 in the fixed frame when the keeper plate is in the release position. Slot 62 is however, positioned partially to 20 secure slot 30 and opening 32 when the keeper is in the locked position so that a locking edge 64 of the slot: can engage in one or other of the leading or trailing locking recesses 20 or 22. The keeper plate resiliently is biased into the locked position by a leaf spring 66 provided in 25 the guide plate between that end remote from the lip ' 60 and the adjacent end of the keeper plate. Cover 42 provides a. housing for the leading edge of the fixed latch 16 when it is in locked engagement with the keeper plate. In order to lock the openable frame in its fully closed or ajar position to the fixed frame, the openable frame is pivoted into a closed position whereby the free end portion of the fixed latch stem passes through the opening 32 in the fixed frame and slot 30 of the guide plate whereby the leading cam surface 26a engages the locking edge 64. The keeper plate is thereby upwardly displaced upon continued closing movement of the openable frame against its spring bias to bring slot 62 into registry with opening 32 and slot 30 so that the free end portion of the latch passes through the keeper plate. When leading cam surface 26a has passed beyond the locking edge, the keeper plate is spring urged back to its locked position whereby the locking edge 64 of the keeper plate is engaged in the leading 'V' locking recess 20 of the latch. Thus, the openable frame automatically locks in an ajar position relative to the fixed frame. Further closing movement of the openable frame causes the trailing cam surface 24a to engage the locking edge 64 of the keeper plate so that the locking edge rides up the cam surface- 24a and again upwardly displaces the keeper plate into its release position against the bias of spring 66. When the stem of the latch is fully home, the keeper plate is spring urged back to its locked position whereby the locking edge of the keeper plate is engaged in the trailing 'U' locking recess 22 of the fixed latch. Thus, the openable frame automatically locks in a fully closed position relative to the fixed frame. If it is desired to put the openable frame into the locked ajar position ' from the fully closed position i.e. a so- called night venting position, it is simply necessary to push against lip 60 and manually displace the keeper plate upwardly so that the locking edge 64 can ride over tooth 24 and cam surface 24a and relocate in the 'V locking recess 20. It may be necessary also to exert an opening force against the openable frame. However, in many window frame assemblies, notably those formed from plastics material, a sealing member which surrounds the fixed frame opening and which is interposed between the fixed and openable frames when the openable frame is closed provides sufficient resilience automatically to displace the openable frame into its ajar position when the keeper plate is put into its release position. Of course, in order to shift the openable frame into an openable position so that it is not locked to the fixed frame, the keeper plate is manipulated into, or held in its release position while opening movement of the openable frame is effected. Figures 1 and 2 show the latching device in unlocked and locked positions respectively. The fixed frame is attached to an outer frame F of a building and the openable frame carries a glazed assembly G. When the openable frame 14 is in the closed position as shown in Figure 2 and the latching device locked, it will be seen that the fixed latch is inaccessible being partially within the cavity CV created between the frames and partially within the keeper assembly. In some constructions it is envisaged that the fixed latch 16 may be attached to the fixed frame 12 and the keeper assembly carried by the openable frame 14.

Claims: CLAIMS - 14 - 1. In a glazed panel assembly comprising a fixed frame (12) and an openable frame (14) an automatic latching device for locking the openable frame to the fixed frame automatically consequent upon closing movement of the openable frame relative to the fixed frame, said device being characterized by a fixed latch (16) carried ,by one of said fixed or openable frames, an opening (32) in the other of said fixed or openable frames through which the fixed latch extends to lock the frames together, displacable locking means (48) provided by the other of said fixed or openable frames disposed adjacent said opening and remote from said one frame and being operable automatically to engage the ^ixed latch as the pp ^ enable frame is moved to a closed position relative to the fixed frame and release means (60) for disengaging the locking means and the fixed latch. 2. A glazed panel assembly according to claim 1, further characterized in that said fixed latch is adapted to engage said displacable locking means in either of two different locations thereby to lock the openable frame relative to the fixed frame in a closed position or in an ajar position. 3. A glazed panel assembly according to claim 1 or claim 2 further characterized in that the fixed latch is carried by the fixed frame and the displacable locking means is provided by the openable frame. 4. A glazed panel assembly according to claim 1, further characterized in that the fixed latch includes a leading cam surface (26a) for displacing said displacable locking means and a leading locking recess (20) into which a locking edge (64) of said displacable locking means engages to lock the fixed latch and the displacable locking means together, said displacable locking means comprising a keeper plate including an aperture (62) providing, said locking edge, the keeper plate "being ' resiliently slidable with respect to said other of the frames from a locked position, in which the aperture is partially out of register with said frame opening so that the locking edge is located in the leading locking recess to a released position in which the aperture substantially is in register with the frame opening so that the locking edge is clear of the leading locking recess. 5. A glazed panel assembly according to claim 4, further characterized in that the fixed latch includes a trailing cam surface (24a) aligned with said leading cam surface and forming an edge of said leading locking recess and a trailing locking recess (22) spaced from said leading locking recess whereby the locking edge of the keeper plate can be caused to ride over both said cam surfaces and engage in the trailing locking recess thereby to lock the openable frame in an ajar position relative to the fixed frame. 6. A glazed panel assembly according to claim 4 or claim 5, further characterized in that the.slidable keeper plate is disposed within a guide plate 28 in which the keeper " plate is disposed for sliding movement relative thereto, the guide plate having a slot (30) in registry with the frame opening and sized to receive said fixed latch. 7. A glazed panel assembly according to any of claims 4 to 6, further characterized in that the disengaging means comprises a portion of the keeper--plate-(60T; accessible for manipulation to bring the locking edge into and out of engagement with the or each locking recess provided by the fixed latch. 8. A latching device for a glazed panel assembly comprising a fixed frame (12) and an openable frame (14) which device comprises a fixed latch (16) on the openable frame and is characterized by an opening (32) in the fixed _ frame through which a portion of the fixed latch extends when the openable frame is moved to approach a closed position and by displacable locking means (48) provided by the fixed frame automatically to engage the fixed latch in either of two different locations thereby to lock the 0 openable frame in a closed position or in an ajar position and release means (60) for disengaging the locking means and the fixed latch. 9. In a glazed panel assembly comprising a fixed frame 5 (12) and an openable frame (14), an automatic latching device for locking the openable frame to the fixed frame in a closed position or in an ajar position characterized in that locking of the frames together being effected in said closed position or said ajar position automatically 0 consequent upon closing movement of the openable frame relative to the fixed frame.

Inventors: KING DEREK, KING, DEREK
Applicants: KING DEREK, KING, DEREK
Application year: 1987
Main classification: E05C1
IPC codes: E05B15, E05C1