AU2004203558B2 - A Louvre Assembly Locking Mechanism - Google Patents

Description

1 TITLE OF THE INVENTION "A Louvre Assembly Locking Mechanism" 5 BACKGROUND TO THE INVENTION This invention relates to a locking mechanism and more particularly a locking mechanism suited for locking a moveable louvre assembly. 10 According to known louvre constructions, a plurality of louvre blades are mounted at each end to a louvre blade carrier which are in turn pivotally mounted to a pair of opposed side frame elements. Louvre windows are 15 traditionally formed so that the louvre blades pivot about horizontal axes thus the side frames are in a vertical orientation. However, it is also known to have the louvre blades pivot about vertical axes thus the side frame elements are horizontal and located top and bottom in the 20 window opening. However, for the purposes of the present disclosure the more traditional approach of having the louvre blades pivot about horizontal axes will be referred to herein.

2 According to traditional constructions an operating mechanism is employed to simultaneously rotate the louvre blade mounts on one of the side frame elements (the "driven side") . This causes the blade elements to rotate about the 5 horizontal axis which in turn rotates the blade mounts coupled to the other of the side elements (the "non-driven side"). A locking or latching mechanism is provided at the driven 10 side of the louvre window. This mechanism generally includes an over centre action of an operating lever. This over centre action is generally sufficient to prevent manipulation of the louvre window from outside the building by someone wishing to gain unlawful access to the building. 15 When the louvre blades are sufficiently long, or are less structurally rigid e.g. the type of material used to form the blade or the blade being of relatively thin cross sectional thickness, the locking of the louvre window at 20 the driven side does not necessarily provide good latching characteristics at the non-driven side. Also, the weather sealing characteristics, which may be quite adequate at the driven side due to the over centre action ensuring that the louvre blade mounts are drawn tightly together, may not 25 necessarily exist at the non-driven side.

3 While the present invention is particularly directed to louvre windows which would typically be used on the exterior of the building, the invention is not limited to 5 such constructions. The louvre construction may be for an internal "window" or may equally be part of a partition or form a louvre door. The present invention is applicable to all such applications as well as to louvres where the louvre blades pivot about both horizontal and vertical 10 axes. Reference to any prior art in this specification does not constitute an admission that such prior art forms part of the common general knowledge. 15 SUMMARY OF THE INVENTION It would be desirable to provide a locking mechanism which is suitable for locking the non-driven side of a louvre 20 window. It would also be desirable to provide a locking mechanism for the non-driven side of a louvre window wherein the locking mechanism ensures a good seal between the louvre 25 blades at the non-driven side.

4 (Followed by 4a) Broadly according to one aspect of the present invention there is provided a locking mechanism for the non driven side of a moveable louvre assembly, said non 5 driven side having a plurality of louvre mounts pivotally coupled to a side member, the locking mechanism having an unlocked position and a locking position and including: at least one control member engageable with the 10 louvre mounts to form a drive train whereby the louvre mounts can be moved simultaneously, a handle, coupling means coupling the handle to the drive train whereby an angular displacement of the louvre 15 mounts can be effected by a movement of the handle, and a latching means operative in response to movement of the handle to lock the drive train in the locking position, 20 wherein in the unlocked position the control member is disengaged from the louvre mounts. According to a preferred form of the invention the handle is a pivotally mounted lever- 4a (Followed by 5) Preferably the handle is moveable between unlocked and locked positions and the coupling means is arranged to induce movement of the at least one control member during 5 movement of the handle between said positions. Preferably the handle causes operation of the latching means to occur at after completion of an angular sealing displacement of the louvre mounts.

5 Preferably the latching means includes a latch element which is engageable with the handle control member to lock the control member against movement. 5 According to one form of the invention there is also provided a key lock mechanism to effect operation of the locking mechanism to an unlocked state. BRIEF DESCRIPTION OF THE DRAWINGS 10 In the following more detailed description of the preferred embodiment of the present invention, reference will be made to the accompanying drawings in which: 15 Figure 1 is a perspective view of a partial length of the non-driven side of a louvre window construction, the view being such as to look into the interior of the side member and showing a locking mechanism 20 according to the present invention, the locking mechanism being in the unlocked state, Figure 2 is an elevation view of the arrangement as shown in Figures 1, 25 6 Figures 3 is a view similar to Figure 2 but showing the locking mechanism moved toward a closed position, Figure 4 is a perspective view of the locking 5 mechanism in the closed (locked) position, Figure 5 is an elevation view of the arrangement as shown in Figure 4, 10 Figure 6 is an exploded view of the components of the locking mechanism, and Figure 7 is an exploded view in an opposite direction to Figure 6. 15 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION According to a typical louvre window construction, the non 20 driven side of the louvre window consists of a vertical side member 10 which typically will be of channel cross section shape as shown in the accompanying drawings. The end of each louvre blade (not shown) is coupled to the side member 10 by a louvre blade mount M. The louvre blade 25 mount M can have a spigot which is engaged through an opening in the floor 11 of the side member 10 as for 7 example shown in New Zealand patent specifications 195283 or 328726. According to the constructions disclosed in NZ 195283 and 5 328726 the spigot can be provided with a pair of opposed projections which are able to engage through similarly disposed and shaped cut outs formed with the opening in the floor 11. The arrangement is such that the spigot is inserted into the opening and then rotated whereupon in 10 normal use of the louvre window the mount never returns to an angular position whereupon the projections align with the cut outs. The louvre blade mount is therefore captured with the side member 10. 15 Other arrangements can be used. For example, according to the arrangement illustrated, the louvre blade mount M can have a pair of finger elements 12 which extend through a central opening 13 in the floor 11 of the side member 10 and snap lock within the central opening 13 in a disc 14. 20 The disc 14 is located within the confines of the channel shape of the side member 10. The disc 14 has a plurality of teeth 14a. A cap (not shown) snap locks onto the turret or curved walls 14b of disc 14.

8 In the driven side of the louvre window it is usual to have one or a pair of control bars which connect the various spigots of the louvre mounts so that linear movement of one control bar, by an external handle, causes simultaneous 5 movement all of the louvre blade mounts. Such an arrangement is not required in the non-driven side of the louvre window as the mounts simply rotate in response to movement of the louvre blades resulting from operation of the driven side of the louvre window. 10 According to the present invention, however, there is provided in the side member 10 at least one, but preferably a pair, of linearly moveable bars 15 which span over the discs 14 of the louvre blade mounts M. The moveable bar 15 15 is provided with cutouts 15a which, as shown in Figures 1, 2 and 3 provide a clearance so that the bar 15 does not interfere with the rotation of discs 14 of the louvre blade mounts. Thus each louvre blade mount M is free to rotate in response to the movement of the louvre blade with which 20 it is associated. As can be seen in the drawings, bars 15 are located adjacent legs 16 and 17 of the side member 10. A cut-out portion in the leg 17 forms an opening to which further 25 reference will be made in the following. This permits 9 installation of the locking mechanism which includes a first cover portions 18 and a second cover portions 18a. These cover portions are, in the assembled mechanism, coupled together by fasteners 48 and 49 (see Figures 6 and 5 7). Cover portions 18 and 18a combine to form a housing which contains and mount the majority of the operational element of the locking mechanism. Pivotally mounted between covers 10 18 and 18a is a lever 19. The lever handle 19 is able to pivot about a pivot axis of pivot boss 20 (see Figure 6). As shown the lever 19 can be pivoted from an unlocked position (Figures 1, 2 and 3) to a locked position (Figures 4 and 5). It will be appreciated that in Figures 1 to 5 15 the cover section 18a is removed to enable the lock mechanism to be viewed. A link 21a has an end thereof located in a bifurcated portion of lever handle 19. The link 21a, which is 20 pivotally mounted by pivot 21b to lever 19, extends from one side of the lever 19 to couple with plate 21. Plate 21 has, at its distal end, a substantially U-shaped slot 22. Engaged in this slot 22 is a pin 23 projecting from control bar 15. Adjacent to the end of plate 21 where it couples 10 to link 21a is an aperture 24 in which is engaged pin 23a of the other control bar 15. A pivot 26 couples plate 21 to a fixture 27 which projects 5 from cover 18. Slidingly mounted, adjacent the leg 17 of the channel shaped side member 10 is a slide member 30. A spring S is engaged between an end of slide member 30 and an 10 abutment 38 of the cover section 18. The spring S biases the slide member 30 in a direction away from abutment 38. A rebate 31 in the top end of slide member 30 engages with pin 42 of a lock barrel 43 (located in lock housing 41). 15 The engagement of pin 42 and rebate 31 at least in part limits the distance by which the slide member 30 can slide upwards under the influence of spring S (see Figures 1, 2 and 3). The lock barrel 43 can be a standard pin or wafer lock barrel operable, in the normal manner, by a key K to 20 move lock pin 42. The slide member 30 further includes a pair of aligned spaced apart elongate slots 32 and 33 which engage over elongate guide elements 33 and 34 of the cover section 18. 25 An offset portion 36 of the slide member 30 furthermore 11 sliding engages in a channel shaped guide 37 of fixture 37. The slide member 30 can thus slide in a stable and secure manner relative to cover section 18. 5 At the end of the slide member 30 adjacent the connection point with spring S there is provided a transversely disposed locking abutment 39. This abutment 39 has an inclined surface 44. 10 Lever handle 19 incorporates a tongue 45. This tongue 45 includes an inclined surface 46. Accordingly, when the lever 19 is moved from an open position toward a closed position the inclined surfaces 44 and 46 engage. This engagement results in a sliding movement of slide 30 15 against the bias of spring S. The tongue 45 thus rides over the transverse abutment 39 until the surface 44 thereof clears the inclined surface 46 of tongue 45 whereupon the biasing effect of spring S forces the slide member upwardly so that the abutment 39 engages into recess 20 47 of lever 19. The lever 19 thus becomes locked into the locked position. This movement of the lever 19 from an open position (say the position of Figure 2) to the locked position, as shown 25 in Figure 5, causes plate 21 to pivot about the axis of 12 pivot 26. The control bars 15 are thus caused to move in contra-directions to lock (as hereinafter described) the louvre mounts M in the closed position (Figure 5). 5 The contra-longitudinal movement of the bars 15 (when the mounts M have moved to the closed position) will result in edge 15b of each cut-out 15a coming into engagement with a tooth 14a of each of the discs 14. This starts to occur as the lever 19 moves to the position shown in Figure 3. This 10 corresponds to the louvre mounts M being in a closed position having been moved to such position from the driven side of the louvre window. However, as lever 19 moves into its locked position the Mounts M will be moved (angularly displaced) further because the engagement of edges 15b with 15 tooth 14a cause rotation of disc 14 to occur. Consequently the louvre blade mounts M will be assured of moving into a fully closed position because of this additional angular displacement. This will thereby optimise 20 the weather sealing of the louvre blades at and adjacent the non-driven side of the louvre assembly. Due to the engagement of transverse abutment 39 with tongue 45 the movement of lever 19 to a closed position 25 automatically results in locking of the louvre mounts M in 13 the closed and sealed position. To enable the louvre mounts M to be moved to an open position the key K of the lock cylinder 43 is operated so as to rotate pin 42 (relative to the longitudinal axis of the lock cylinder 5 43). This rotation of pin 42 effectively causes the pin 42 to move in a downward arc. Due to the engagement of pin 42 in rebate 31 the downward movement of pin 42 causes the slide member 30 to move downwardly against the biasing effect of spring S. 10 This downward movement of the slide member 30 moves the transverse abutment 39 to a position below the lowermost extremity of tongue 45. As a consequence the lever handle 19 is now able to be moved to an open position. Release of 15 the key K results in pin 42 reverting to its normal position thereby allowing the slide member 30 to move upwardly under the influence of spring S. The locking mechanism is thus ready to automatically re-engage when the lever 19 when the lever is next moved to the fully closed 20 position. The locking mechanism, according to the present invention, thus provides a means of locking the non-driven side of a louvre window construction. It also ensures good sealing 25 between the louvre blades.

14 The mechanism is also one which applies a pre-load during final movement to the locked position to thereby cause the louvre blades to move into an optimised sealing position. 5 This pre-load is provided in an attempt to compensate for the manufacturing tolerances that are evident with the typical manufacturing processes associated with the production of louvre blade systems. As louvres are typically produced of multiple blades it is common for 10 "tolerance stacks" to affect the overall way that elements interact with each other. This is particularly evident with respect to the sealing action of the louvre blades. Accordingly, the previously described opening formed by the 15 cut out in leg 17 of the louvre channel 10 is dimensioned such that the cover portions 18 and 18a, that contain the majority of the elements of the locking mechanism, are not fully constrained in the vertical direction. However, the mounting of the housing 18 and 18a is such that the housing 20 is retained from movement in a direction perpendicular to the plane of leg 17. This retention against movement in a direction perpendicular to leg 17 can be achieved by suitable positioning of flanges in the cover portions 18 and 18a which engage either side of the leg 17 when the 25 housing is located in position on the channel 10.

15 The action of moving the locking mechanism from an unlocked position to a locked position by movement of the lever handle 19 initiates a pivotal movement of plate 21 which 5 generates a corresponding contra-directional movement of the control bars 15 (as previously described). The effect of generating this movement towards the end of the action of the lever handle 19 is to apply a pre-load on the louvre mounts M which are in engageable contact with the control 10 bars 15 and interact with each other. The effect of this action may require the housing 18,18a to move vertically upwards or downwards to allow equal load to be applied to the opposing control bars 15. 15 This ability of the construction, as described and illustrated herein, to apply an equal load in opposite directions ensures that an optimum sealing action is achieved in the louvre window assembly. It also has the affect of reducing the accuracy of the position and size of 20 the opening formed in legs 17 of the louvre channel 10, thereby reducing the cost to produce the mechanism reliably in a commercialised form. Consequently, not only does the mechanism provide a means 25 of locking but also a means of ensuring that the non-driven 16 ends of the louvre blades are moved into a good sealing position. It will be apparent to those skilled in the art that the 5 invention is open to modification within the scope and spirit of the invention. For example the drive train formed by bars 15 and discs 14 could be moved by a different mechanism. Also the lock pin could engage with some other part of the drive train rather than bar 15 e.g. 10 one of the louvre mounts.

Claims (19)

1. A locking mechanism for the non-driven side of a 5 moveable louvre assembly, said non-driven side having a plurality of louvre mounts pivotally coupled to a side member, the locking mechanism having an unlocked position and a locking position and including: at least one control member engageable with the 10 louvre mounts to form a drive train whereby the louvre mounts can be moved simultaneously, a handle, coupling means coupling the handle to the drive train whereby an angular displacement of the louvre 15 mounts can be effected by a movement of the handle, and a latching means operative in response to movement of the handle to lock the drive train in the locking position, 20 wherein in the unlocked position the control member is disengaged from the louvre mounts.

2. A locking mechanism as claimed in claim 1 wherein the handle is a pivotally mounted lever. 25 18

3. A locking mechanism as claimed in claim 1 further including a housing which is attachable to the side member, said handle pivotally coupled to the housing. 5

4. A locking mechanism as claimed in claim 1, 2 or 3 wherein the handle is moveable between locked and unlocked positions and the coupling means is arranged to induce movement of the at least one control member during movement of the handle between said locked and 10 unlocked positions.

5. A locking mechanism as claimed in any one of the preceding claims wherein the handle causes operation of the latching means to occur after completion of 15 said angular displacement of the louvre mounts.

6. A locking mechanism as claimed in any one of the preceding claims wherein the latching means includes a latch element which is engageable with the handle to 20 lock the handle against movement.

7. A locking mechanism as claimed in claim 6 wherein the latch element is a slideable element which is biased by a biasing means into a latching position, the latch 19 element having an engagement element which engages with the handle to lock the handle against movement.

8. A locking mechanism as claimed in any of the preceding 5 claims further including a key lock mechanism to effect operation of the locking mechanism to an unlocked state.

9. A locking mechanism as claimed in claim 7 further 10 including a key operable lock mechanism to cause the slideable element to move against the biasing effect of the biasing means to move the engagement element out of engagement with the handle. 15

10. A locking mechanism as claimed in claim 7 or 9 wherein the handle includes an engagement surface which is contactable with the engagement element as the handle moves toward the locked position to cause the slideable element to move against the biasing effect 20 of the biasing means, the handle further including a recess into which the engagement element moves upon the engagement surface moving clear of the engagement element. 20

11. A locking mechanism as claimed in any one of claims 1 to 10 wherein the or each control member is an elongate element which is moveable in a direction of a longitudinal axis of the elongate member. 5

12. A locking mechanism as claimed in claim 11 wherein the or each control member has a recessed portion which includes a contact surface engageable with a part of the louvre mount to cause said angular displacement to 10 occur.

13. A locking mechanism as claimed in claim 11 or 12 wherein there are two spaced apart parallel control members, the coupling means being a link pivotal about an axis located between the control members, the link 15 being coupled to each control member and coupled to said handle.

14. A locking mechanism as claimed in claim 13 wherein the link is pivotally coupled to a second link, said 20 second link being pivotally coupled to the handle.

15. A locking mechanism as claimed in claim 13 or 14 wherein the link has a pair of elongate apertures, a spigot on each control member being engaged in 25 respective ones of the elongate aperture. 21

16. A louvre window assembly including a locking mechanism as claimed in any one of the preceding claims incorporated at the non-driven side of the assembly. 5

17. A louvre window assembly including a driven side and a non-driven side, each side having a plurality of louvre mounts, louvre blades, in use, being engaged between opposed pairs of louvre mounts of the driven 10 and non-driven sides, the non-driven side having a channel element with which the louvre mounts are rotatably engaged, a locking mechanism as claimed in claim 1 incorporated with the non-driven side, said locking mechanism including a housing with. which the 15 handle is mounted, said housing being restrained against substantial movement laterally to a side of the channel element with which it is mounted but retained for limited movement longitudinally with respect to the length of the channel element. 20

18. A louvre window assembly incorporating a non-driven side in combination with a locking mechanism substantially as herein described with reference to the accompanying drawings. 25 22

19. A locking mechanism for the non-driven side of a louvre assembly substantially or herein described with reference to the accompanying drawings. 5 DATED this 4th day of August 2004 Assa Abloy Financial Services AB 10 PATENT ATTORNEYS FOR THE APPLICANT DON HOPKINS & ASSOCIATES