GB2055955A

GB2055955A - Restricted movement pivots

Info

Publication number: GB2055955A
Application number: GB7927834A
Authority: GB
Original assignee: MELLOWES METFAB Ltd
Current assignee: MELLOWES METFAB Ltd
Priority date: 1979-08-09
Filing date: 1979-08-09
Publication date: 1981-03-11
Also published as: GB2055955B

Abstract

A friction pivot assembly for a window has a pivot (1) securable to a fixed frame and a spring biassed sliding chute (14) mounted on the window, the chute having a profiled slot (13) cooperable with the upper shaped end 12 of the pivot(1). In a first position of the chute, the slot non-rotatably engages the pivot at 21, in a second position the pivot may rotate (righthand end of the slot), and in a third position the relative rotation of the pivot is restricted by a predetermined amount. The cylindrical body of the pivot is located in a bearing provided with friction liners which may be adjusted to vary the frictional force opposing the rotation of the pivot. By these means, a reversible window may be locked in a closed or fully reversed position or may be limited to a restricted opening for ventilation purposes. <IMAGE>

Description

SPECIFICATION Friction pivot assembly This invention relates to a friction pivot assembly for use with windows, particularly reversible windows.

BS 4873 :1 972 prescribes inter alia security and safety standards for aluminium alloy windows. For instance, large opening lights that may need to be left open by small amounts for ventilation shall be provided with fittings which restrict the lights in their ventilating position without loss of security. Further, for safety purposes, it may be specified that iimit catches shall check the opening of any large opening light at an aperture of about 100 mm. To permit the windows to be opened more widely, the catches shall be capable of being released by means that are not readily operable by small children, and the catches shall reengage automatically when the windows are closed.Reversing catches, where specified, shall hold pivoted windows firmly when reversed, and shall need some deliberate action to undo them when the window is to be closed.

These and further requirements may be satisfied by a pivot assembly according to this invention.

In one aspect this invention consists in a friction pivot assembly comprising a pivot securable at one end to a first frame member, the other end having an axial extension and between the ends, a cylindrical body portion rotatably retained by a bearing mounted in a second frame member, the bearing frictionally opposing the relative rotation of the pivot, the extension being cooperable with a radially movable chute retained by a guide on the second frame member, the chute having a profiled slot which in a first radial position non-rotatably retains the pivot, in a second radial position is disengaged from the extension and in a third radial position constrains the relative angular rotation of the pivot by a predetermined amount, and means being provided for radially moving the chute.

In order that the invention may be more clearly understood one embodiment will now be described by way of example only with reference to the accompanying drawings in which Figure 1 is a cross sectional elevation of a friction hinge assembly fitted between a fixed and an openable window frame, and Figures 2 to 5 are isometric views of the components of the assembly illustrated in Figure 1.

Referring to the drawings, a pivot (1) fitted to a load bearing base plate (2) is seated in the channel of an extruded aluminium alloy glazed window frame (3). The cylindrical body portion of the pivot (1) is rotatably retained in a bearing formed by support blocks (4) and (5) which are radially adjustabie with respect to the pivot (1) by means of adjustment screws (7) and (8) the inner ends of which are threaded into tapped holes in blocks (4) and (5), the outer ends abuting fixed anchor blocks (9) and (10). Semi-cylindrical friction liners (11) are urged into contact with pivot (1), frictionally opposing the relative rotation of the pivot during use.

The upper end of the pivot (1) has an axially directed extension (12) which enters a profiled slot (13) formed in a chute (14) retained by guide (1 5) housed within the channel of the fixed window frame (6). A manually operable slide control (16), which is operatively connected to the chute (14) by means of a pin (20), is retained by a guide (17), is attached by means of screws passing through the wall of frame (6), to the tapped end blocks (18) of securing blocks (4) and (5).

The slide control (16) is provided with a depressible spring actuated catch (19) which engages the edge of slot (24) formed in the guide (17). The slide control (16) is biassed to a central position of slot (24) by means of a spring, not illustrated, housed within the guide (17).

The profiled slot (13) formed in chute (14) has a parallel sided central portion into which the extension (12) may be non-rotatably received constituting a first operative position, with frame (3) being either in the closed position, or rotated by 1800 to the fully open reversed position.

With the window frame (3) locked in the closed position, the window may be fully opened and reversed by depressing the safety catch (19) and moving the slide control to the left, as seen from Figure 5 constituting a second operative position.

Chute (14) slides in guide (15) to the left, the extension (12) entering the circular end portion of the profile the diameter of which is greater than the width of extension (12), thus permitting free relative rotation between pivot (1) and the chute (14).

The rotation of frame (3) to which the pivot (1) is secured may therefore be continued for 1 800 until the extension (12) is again aligned with the central parallel sided portion (21) of slot (13).

Since the slide control (16) is spring biassed towards its central position, chute (14) automatically slides to its first operative position in which the extension (12) is non-rotatably retained by the slot position (21) so as to lock the window in its fully reversed position, the safety catch (19) automatically springing into its engaged position once more.

A third operative position is obtained by moving slide control (16) to the right, as seen from Figure 5. Chute (14) moves to the right, the extension (12) entering the opposite end portion of the slot (13) having pitched abutment surfaces (22). The angle 0, through which the extension (12) may rotate may be selected to provide a required ventilation gap, suitably 100 mm, at the edge of the window. The slide control (16) is retained in this position by the engagement of a ball catch (23) in a depression machined in the back face of the front wall of guide (17).

1. A friction pivot assembly comprising a pivot securable at one end to a first frame member, the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Friction pivot assembly This invention relates to a friction pivot assembly for use with windows, particularly reversible windows. BS 4873 :1 972 prescribes inter alia security and safety standards for aluminium alloy windows. For instance, large opening lights that may need to be left open by small amounts for ventilation shall be provided with fittings which restrict the lights in their ventilating position without loss of security. Further, for safety purposes, it may be specified that iimit catches shall check the opening of any large opening light at an aperture of about 100 mm. To permit the windows to be opened more widely, the catches shall be capable of being released by means that are not readily operable by small children, and the catches shall reengage automatically when the windows are closed.Reversing catches, where specified, shall hold pivoted windows firmly when reversed, and shall need some deliberate action to undo them when the window is to be closed. These and further requirements may be satisfied by a pivot assembly according to this invention. In one aspect this invention consists in a friction pivot assembly comprising a pivot securable at one end to a first frame member, the other end having an axial extension and between the ends, a cylindrical body portion rotatably retained by a bearing mounted in a second frame member, the bearing frictionally opposing the relative rotation of the pivot, the extension being cooperable with a radially movable chute retained by a guide on the second frame member, the chute having a profiled slot which in a first radial position non-rotatably retains the pivot, in a second radial position is disengaged from the extension and in a third radial position constrains the relative angular rotation of the pivot by a predetermined amount, and means being provided for radially moving the chute. In order that the invention may be more clearly understood one embodiment will now be described by way of example only with reference to the accompanying drawings in which Figure 1 is a cross sectional elevation of a friction hinge assembly fitted between a fixed and an openable window frame, and Figures 2 to 5 are isometric views of the components of the assembly illustrated in Figure 1. Referring to the drawings, a pivot (1) fitted to a load bearing base plate (2) is seated in the channel of an extruded aluminium alloy glazed window frame (3). The cylindrical body portion of the pivot (1) is rotatably retained in a bearing formed by support blocks (4) and (5) which are radially adjustabie with respect to the pivot (1) by means of adjustment screws (7) and (8) the inner ends of which are threaded into tapped holes in blocks (4) and (5), the outer ends abuting fixed anchor blocks (9) and (10). Semi-cylindrical friction liners (11) are urged into contact with pivot (1), frictionally opposing the relative rotation of the pivot during use. The upper end of the pivot (1) has an axially directed extension (12) which enters a profiled slot (13) formed in a chute (14) retained by guide (1 5) housed within the channel of the fixed window frame (6). A manually operable slide control (16), which is operatively connected to the chute (14) by means of a pin (20), is retained by a guide (17), is attached by means of screws passing through the wall of frame (6), to the tapped end blocks (18) of securing blocks (4) and (5). The slide control (16) is provided with a depressible spring actuated catch (19) which engages the edge of slot (24) formed in the guide (17). The slide control (16) is biassed to a central position of slot (24) by means of a spring, not illustrated, housed within the guide (17). The profiled slot (13) formed in chute (14) has a parallel sided central portion into which the extension (12) may be non-rotatably received constituting a first operative position, with frame (3) being either in the closed position, or rotated by 1800 to the fully open reversed position. With the window frame (3) locked in the closed position, the window may be fully opened and reversed by depressing the safety catch (19) and moving the slide control to the left, as seen from Figure 5 constituting a second operative position. Chute (14) slides in guide (15) to the left, the extension (12) entering the circular end portion of the profile the diameter of which is greater than the width of extension (12), thus permitting free relative rotation between pivot (1) and the chute (14). The rotation of frame (3) to which the pivot (1) is secured may therefore be continued for 1 800 until the extension (12) is again aligned with the central parallel sided portion (21) of slot (13). Since the slide control (16) is spring biassed towards its central position, chute (14) automatically slides to its first operative position in which the extension (12) is non-rotatably retained by the slot position (21) so as to lock the window in its fully reversed position, the safety catch (19) automatically springing into its engaged position once more. A third operative position is obtained by moving slide control (16) to the right, as seen from Figure 5. Chute (14) moves to the right, the extension (12) entering the opposite end portion of the slot (13) having pitched abutment surfaces (22). The angle 0, through which the extension (12) may rotate may be selected to provide a required ventilation gap, suitably 100 mm, at the edge of the window. The slide control (16) is retained in this position by the engagement of a ball catch (23) in a depression machined in the back face of the front wall of guide (17). CLAIMS

1. A friction pivot assembly comprising a pivot securable at one end to a first frame member, the other end having an axial extension and between the ends, a cylindrical body portion rotatably retained by a bearing mounted in a second frame member, the bearing frictionally opposing the relative rotation of the pivot, the extension being cooperable with a radially movable chute retained by a guide on the second frame member, the chute having a profiled slot which in a first radial position non-rotatably retains the pivot, in a second radial position is disengaged from the extension and in a third radial position constrains the relative angular rotation of the pivot by a predetermined amount, and means being provided for radially moving the chute.

2. A hinge as claimed in Claim 1 wherein the means for radially moving the chute consists in a slide control retained by a guide disposed on the exterior of the second frame member, the slide control being operatively connected to the plate, and biassing means being provided to biass the control slide towards the first operative position.

3. A hinge as claimed in Claim 2 wherein the slide control is provided with a spring actuated catch which, in the engaged position, cooperates with the guide preventing the movement of the slide between the first and second operative positions.

4. A hinge as claimed in any preceding Claim wherein the bearing consists in a pair of support blocks retaining semi cylindrical friction liners in contact with the cylindrical body portion of the pivot, the blocks being radially adjustable with respect to the body whereby the frictional force opposing the relative rotation of the pivot may be varied.

5. A friction hinge assembly substantially as described with reference to the accompanying drawings.