Espagnolettes

Abstract: A locking mechanism is provided for use with an espagnolette, the locking mechanism comprising at least one locking member 10, at least one strike member 16 having a recess 17 therein, and operating means to move the locking member 10 into the recess 17 and then behind the strike member 16, to lock the members together. The locking mechanism according to the invention enables an espagnolette to be made more secure against unauthorised entry. The invention includes espagnolettes and panels fitted with a locking mechanism according to the invention.

Description: The invention relates to espagnolettes. Espagnolettes are well known and comprise a fastening for a panel such as a door or window in which two long bolts can be moved into sockets at the top and bottom, or each side, of a surrounding frame to lock the panel in the closed position. The bolts are usually operated by a member rotatable by a handle, the inner ends of the bolts being connected to the member at a point offset from the axis of rotation of the member. The object of the invention is to provide an espagnolette which provides more secure locking against unauthorised entry. EP-A-0 578 004 discloses a locking mechanism comprising at least one locking member, at least one strike member having a recess therein, and operating means to move the locking member into the recess and then behind the strike member to lock the members together. The locking member has a return spring, but movement of the locking member into the locking position is controlled by movement of a pin 20 along a track. Thus, the locking member moves along a predetermined path which is fixed. If this locking mechanism is used with a door assembly where the door has not been very accurately positioned within the door frame, the locking member may come into contact with the door frame before it has reached the end of its predetermined travel, thus preventing the locking member from moving into the locking position. EP-A-0 789 121 also discloses a locking mechanism in which movements are controlled in a fixed manner which can lead to the jamming of components against a door frame. The invention provides a locking mechanism for use with an espagnolette, the locking mechanism comprising at least one locking member, at least one strike member having a recess therein, and operating means to move the locking member into the recess and then behind the strike member, to lock the members together, there being spring means to bias the locking member into the locking position. Preferably there are a plurality of locking members spaced apart, each associated with a cooperating recess. The recesses may be provided by slots in a unitary strike plate. Each locking member may comprise a tooth pivotally mounted on a support, for movement between a locking position in which the tooth projects into and behind a recess, and a retracted position in which the tooth is flush with the support. The operating means may be arranged to move the, or each tooth from the retracted position, in which the tooth is held retracted, against the action of the spring means, by inter-engagement with part of the support, through an extended position, in which the tooth is free to extend into the associated recess under the action of the biasing means, and then on into the locking position. The operating means is preferably connected to an operating device for the espagnolette. The strike member may be provided with at least one auxiliary recess, laterally spaced from the main recess, such that a panel may be locked in an alternative, slightly open position, for example to provide night ventilation. The invention includes an espagnolette provided with a locking mechanism as defined above. The invention includes a panel provided with an espagnolette according to the invention. The panel may comprise a door or window. By way of example, a specific embodiment of the invention will now be described, with reference to the accompanying drawings, in which :- Figure 1 is a perspective view of an embodiment of locking mechanism according to the invention, in the configuration which will be adopted when the associated window or door is open; Figure 2 is a perspective view of the underside of the locking mechanism shown in Figure 1; Figure 3 is a perspective view of the mechanism in the position in the configuration which will be adopted when the window or door is closed; Figure 4 is a view of the underside of the locking mechanism of Figure 3; Figure 5 is a view of the locking mechanism in the configuration of Figure 3 with an upper plate removed; Figure 6 shows the locking mechanism associated with a strike plate of a surrounding frame; Figure 7 is a perspective view illustrating how several locking teeth may be provided, spaced apart along the length of the mechanism; and Figure 8 is a diagrammatic cross section through part of a window and frame, showing how the locking mechanism is positioned in use. The mechanism shown in Figure 1 operates utilising a plurality of teeth 10 spaced apart along an edge of a window or door. Only one tooth is described in detail, but it will be appreciated from Figure 7 that there may be any desired number of teeth, dependent on the size of the window or door. Each tooth 10 is mounted in a tooth housing 12. The tooth housing 12 is attached to a drive bar 13. These components are housed within a outer channel 14 which has a plurality of slots 15 therein, one for each tooth 10. The drive bar is attached to a gear box for operating the locking mechanism, and the gear box (not shown) may, for example, be mounted on the fixed channel 14. The teeth 10 are arranged to cooperate with slots in a striker plate 16 which is fixed to the surrounding window frame or door frame. There is one slot 17 for each tooth 10. As best seen in Figure 5, each tooth 10 has a shoulder 18 near to its pivot point, a side lip 19 and a front lip 20. When the window is to be opened, the teeth have the configuration shown in Figures 1 and 2, in which they are retracted into the channel 14, so that they are not performing any locking function. The teeth are, in fact, spring loaded by springs (not shown) into the configuration shown in Figures 3 and 4, but when the handle attached to the gear box is turned to the open position, the drive bar 13, together with the tooth housing 12, is moved to a position such that the channel 14 overlies each tooth shoulder 18 so the teeth are held in the retracted position shown in Figures 1 and 2. When it is desired to lock the window or door, the window or door is moved to the closed position, and the handle is then turned to the locking position. This action moves the drive bar and tooth housing relative to the channel 14. Firstly, the shoulder 18 of each tooth moves from underneath the channel 14, enabling the teeth to pivot, under the action of the springs, into the projected position shown in Figures 3 and 4. In this position, the teeth extend into the slots 17 of the striker plate. As movement of the drive bar and tooth housing is continued, the leading ends of the teeth pass over the striker plate 16. In this position the teeth 10 cannot move back out of the slots 17 until the handle is returned to the open position. If desired, one or more additional slots 21 may be provided in the striker plate 16, offset from the slots 17, for example to provide a night vent position for a window, in which the window can be locked against unauthorised entry, but is not fully closed, so that ventilation can take place. It will be seen from Figure 6 that each slot 17 is narrower at its right hand end. In the closed position, the narrower end of the slot cooperates with the leading end of the associated tooth to reduce the risk of a window or door being forced open by an unauthorised person using a screwdriver or other tool. The reason why the tooth cannot be forced back out of the slot 17 is because of the side lip 19. This means that the leading end of each tooth is wider than the narrow portion of each slot 17. The front lip 20 projects at a slight angle from the rest of the tooth to reduce the risk that the tooth will dig in to the strike plate as it moves along the strike plate. Figure 8 shows the locking mechanism in use. Part of the openable window is shown at 22 and part of the fixed surrounding frame is shown at 23. The striker plate 16 is fixed to the frame 23 and the channel 14 is fixed to the window section 22. The mechanism is shown in the locked position in which the teeth 10 are engaging underneath the striker plate 16. When it is desired to open the window the operating handle is turned, moving the drive bar 13 in a direction perpendicular to the plane of the paper, as viewed in the figure. This movement firstly moves the teeth out from under the striker plate 16 and then retracts the teeth into the position shown in figures 1 and 2. The window can then be pushed open in the direction of arrow A. The locking mechanism according to this embodiment has advantages which include the following: 1. The teeth are fully retracted in the open position, allowing greater tolerance when fixing the window or door in the frame. The tolerances may for example be plus or minus 5mm. 2. Since the teeth are spring loaded, they automatically find the correct working position, again easing manufacturing and fitting tolerances. 3. The teeth are flush with the window lock and there is no need for protruding members such as the cams of prior art devices. 4. Because the teeth form a substantial interlock with the striker, they form a very strong connection. The locking surface area may be up to 20 times greater than with a prior art cam. 5. The striker may be made from a one piece steel pressing, including stainless steel. This allows more fixing points to be made with reinforced steel within the window component. The one piece striker can also butt up against plastic window or door webs and can take advantage of the natural strength of the frame by spreading the load. 6. Because of advantages 1, 2 and 6, this embodiment of locking device saves considerable assembly time. Other arrangements are possible. For example in stead of engaging with the striker plate, the teeth may engage behind a keep or any other appropriate device attached to the surrounding frame. The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

Claims: . A locking mechanism for use with an espagnolette, the locking mechanism comprising at least one locking member (10), at least one strike member (16) having a recess (17) therein, and operating means (13) to move the locking member into the recess and then behind the strike member, to lock the members together; characterised in that there is spring means to bias the locking member into the locking position. A locking mechanism as claimed in claim 1, in which there are a plurality of locking members (10) spaced apart, each associated with a cooperating recess (17). A locking mechanism as claimed in claim 2, in which the recesses are provided by slots (17) in a unitary strike plate. A locking mechanism as claimed in claim 2 or claim 3, in which each locking member (10) comprises a tooth pivotally mounted on a support, for movement between a locking position in which the tooth projects into and behind a recess (17), and a retracted position in which the tooth is flush with the support. A locking mechanism as claimed in claim 4, in which the operating means (13) is arranged to move the, or each tooth (10) from the retracted position, in which the tooth is held retracted, against the action of the spring means, by inter-engagement with part of the support, through an extended position, in which the tooth is free to extend into the associated recess under the action of the biasing means, and then on into the locking position. A locking mechanism as claimed in any one of the preceding claims, in which the operating means (13) is connected to an operating device for an espagnolette. A locking mechanism as claimed in any one of the preceding claims, in which the strike member (16) is provided with at least one auxiliary recess, laterally spaced from the main recess, such that a panel may be locked in an alternative, slightly open position, for example to provide night ventilation. An espagnolette provided with a locking mechanism as claimed in any of the preceding claims. A panel provided with an espagnolette as claimed in claim 8. A panel as claimed in claim 9, comprising a door or window.

Inventors: PARKER TERENCE, WALLIS GLEN WILLIAM, PARKER, TERENCE, WALLIS, GLEN WILLIAM
Applicants: MILA HARDWARE LTD, MILA HARDWARE LIMITED
Application year: 2000
Main classification: E05C9
IPC codes: E05B15, E05B17, E05C9