WO1998014680A1

WO1998014680A1 - A pivot

Info

Publication number: WO1998014680A1
Application number: PCT/NZ1997/000129
Authority: WO
Inventors: John Fischer; Umberto Figliola; Kostadin Boris Kondev
Original assignee: Interlock Group Limited
Priority date: 1996-10-04
Filing date: 1997-10-03
Publication date: 1998-04-09
Also published as: CN1233310A; AU4638897A

Abstract

A pivot for use in the mounting of a window sash and a window frame. The pivot includes a link arm (12) mounted at one end (12a) for mounting to a window frame mounting plate (10) and at the other end (12b) to the window sash mounting plate (11). A sash guide (22) is mounted with the sash plate (11) and a frame guide (23) is mounted with the frame plate (10). The frame and sash guides have interacting guide surfaces (28 and 29) which are in sliding contact and between which relative movement occurs during opening and closing of a window sash mounted by the pivot.

Description

A PIVOT

BACKGROUND OF THE INVENTION

This invention relates to a pivot, more particularly a window

pivot. The pivot is primarily intended for use with large

and consequently heavy openable windows.

In Asia in particular, large and heavy openable windows have

become common especially in high rise buildings. Due to

regulation the windows in such buildings must be openable for

(a) ventilation in the event the ventilation systems fails,

and (b) egress in the event of emergency such as fire. These

windows have come to be referred to as "curtain walling"

because typically they extend from floor to ceiling. Such

windows can therefore typically be in the order of two metres

wide and high and be double-glazed with, for example, 8mm

panes of glass. Thus a single window can typically weigh

about 150kg.

Also due to regulation the window must be openable to a

minimum of 300mm at the lowermost edge (the windows being

awning hung) . Thus typically the window is openable to about 15° . As a result of the limited degree of opening and the

weight of the window it is usual to simply hinge the window

sash to the window frame so that the top edge of the sash

hinges about a fixed pivot. This, however, results in the

window rubbing or sliding over the window seals at final

closing and initial opening of the window with consequential damage to the seals .

A further requirement with such windows is to hold the window

against negative pressures which can pull the window out

under extreme wind conditions. Therefore, any hinge or pivot

must be able to lock the head (ie the hinged side) of the

window sash against negative pressures .

SUMMARY OF THE INVENTION

The object of the present invention is to provide a pivot for

the pivotal mounting of a heavyweight window sash.

A further object is to provide a pivot for a heavyweight

window sash which provides control of the hinged side of the

sash to minimise damage to window seals. It is a further object to provide a pivot for a heavyweight

window sash which provides resistance against the effect of

negative pressures.

Broadly in one aspect of the invention there is provided a

pivot for the mounting of a window sash and a window frame,

the pivot comprising a link arm adapted for pivotal mounting

at one end to the window frame and at the other end to the

window sash, a sash guide adapted for mounting with a window

sash and a frame guide adapted for mounting with the window

frame, said frame and sash guides having interacting guide

surfaces which are in sliding contact and between which

relative movement occurs during opening and closing of a

window mounted by the pivot .

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a plan view of the pivot in the fully closed

position,

Figure 2 is a plan view of the pivot in an open

position, Figure 3 is a perspective view of the pivot in an open

position,

Figure 4 is a plan view of the pivot in the fully closed

position as shown in Figure 1 but with the sash plate 11

removed,

Figure 5 is a plan view similar to Figure 2 but with the

sash plate removed, and

Figure 6 is a plan view similar to Figure 2 of an

opposite handed pivot to that of Figures 1 to 5 and

showing various stages of the opening/closing action of

the pivot .

DESCRIPTION OF THE PREFERRED EMBODIMENT

The pivot comprises a frame plate 10 and a sash plate 11

which are joined by a link arm 12. The frame plate 10 is

adapted for mounting to the frame of a window by mechanical

fasteners (not shown) engaging through openings 13.

Similarly, openings 14 are provided in the sash plate 11 for

mounting of the sash plate to the window sash. With curtain walling a pivot is mounted each side of the sash near the top

of the sash so that the sash is mounted in an awning

configuration .

While shown in one piece each of plates 10 and 11 could be

formed (in a least preferred embodiment) in two separate

pieces as is known in the art.

In a preferred form of the invention the sash and frame

plates are of die cast zinc while the link arm 12 is formed

of stainless steel. Similarly, in a preferred form of the

invention, the rivets 15 and 16 which couple the ends 12a and

12b of link arm 12 to the sash and frame plates are of

stainless steel construction.

In the preferred form of the invention the heads of the

rivets 15 and 16 are formed as large as possible to provide

maximum bearing surfaces so that the pivot bearings are

robust and not prone to wearing. Because the head of the

rivet 16 projects beyond the surface of link arm 12 a groove

17 is formed in the face of the frame plate 10 to accommodate

the head of the rivet as the pivot moves between open and

closed positions. The shank of the rivet 15/16 passes through aligned openings

in the link arm 12 and plate 10/11 with the tail thereof

enlarged in a counterbore in the plate 10/11. A wear

resistant washer, eg of nylon, locates about the shank and

preferably between the opposing faces of the link arm 12 and

plate 10 and 11 respectively to prevent surface to surface

contact where surfaces move relative to one another. This is

substantially in accordance with known window pivot bearing

techniques .

Substantial and positive end stops are provided to limit the

degree of opening of the pivot . These are formed by an

inclined edge 18 at end 12a of the link arm 12 (ie. that

mounted by the pivot bearing 15) engaging against a shoulder

19a formed by end 19 of the frame plate 10. Similarly, an

inclined edge 20 at the other end of the link arm 12 abuts

against surface 21 of sash guide 22.

A frame guide 23 is mounted at what, in use, is the upper end

of the frame plate 10. An opening 24 in the frame guide 23

fits over a pin 25 projecting from the frame plate 10. The

frame guide 23 also engages with an upstand 26 of the frame plate 10, the upstand having a profiled edge 27 which engages

with a similarly profiled edge 30 of the frame guide 23.

Profiled edge 27 provides a recess 31 into which a tongue 32

of profiled edge 30 engages.

The interfitting of edges 27 and 30 and tongue 32 in recess

31 combined with the interaction of opening 24 and pin 25

locks the frame guide 23 against lateral movement as a

consequence of the opening or closing action of a window

mounted by the pivot. The frame guide 23 is further locked

in place by a mechanical fastener which passes through

opening 13 ' in the frame guide 23 which is aligned with an

opening 13 in the frame plate 10 this fastener being

installed at the time of fitment of the frame mounting plate

10 to the window frame.

The frame guide 23 has a curved guide surface 28 while sash

guide 22 has a curved guide surface 29. In the preferred

form of the invention the guide surfaces 28 and 29 are of the

same radius though the centre of radius of the two surfaces

do not coincide. As a consequence, there is only part

contact between surfaces 28 and 29 when the pivot is in the

fully closed position and throughout relative movement between the guides 22 and 23 during opening and closing of

the pivot .

The sash guide 22 is similarly mounted to the sash plate 11

by a pin (not shown) engaging in a correspondingly shaped

elongate opening 33 in the sash guide 22. An opening 14'

enables a mechanical fastener to engage through the sash

guide 22 and an aligned opening 14 in the sash plate 10 and

into the sash of the window when the sash plate 10 is mounted

thereto.

As can be seen in Figure 6, the interaction of the sash guide

22 and frame guide 23 via the sliding guide surfaces 28 and

29 controls the head of the sash and provides the necessary

pull-in characteristics at final closing to ensure that the

sash contacts window seals with minimal or no sliding action.

Thus, not only is damage to the seals minimised but also a

good sealing action between the head end of the sash and the

seals is achieved. Furthermore, the contact of the sliding

guide surfaces 28 and 29 when the window is in the closed

position provides a maximum resistance against movement of

the head of the window in negative pressure situations. The end stops at the open position formed by the interaction

of edges 18 and 20 of the link arm 12 with shoulder 19a and

surface 21 provide substantial end stops in the event that

the window is rapidly forced under windy conditions to its

fully open position.

The pivot according to the present invention thus provides a

substantial mounting for the hinged end of a heavy window

frame and provides for good control of the head of the window

in both negative pressure situations and during final closing

and initial opening of the window so as to minimise damage to

window seals .

Claims

1. A pivot for the mounting of a window sash and a window

frame, the pivot comprising a link arm (12) adapted at

one end (12a) for mounting to the window frame and at

the other end (12b) to the window sash, a sash guide

(22) adapted for mounting with the window sash and a

frame guide (23) adapted for mounting with a window

frame, said frame and sash guides having interacting

guide surfaces (28 and 29) which are in sliding contact

and between which relative movement occurs during

opening and closing of a window sash mounted by the

pivot .

2. A pivot as claimed in claim 1 wherein the link arm (12)

is coupled at said other end (12b) to a sash mounting

member (11) .

3. A pivot as claimed in claim 1 wherein the link arm (12)

is coupled at said one end (12a) to a frame mounting

member (10) .

4. A pivot as claimed in claim 2 wherein the sash guide

(22) is carried by said sash mounting member (11) .

5. A pivot as claimed in claim 3 wherein the frame guide

(23) is carried by said frame mounting member (10) .

6. A pivot as claimed in claim 5 wherein the guide surfaces

(28 and 29) are curved but are not in full surface to

surface contact .

7. A pivot as claimed in claim 5 wherein the guide surfaces

(28 and 29) are curved and are of the same radius of curvature but the centres of radii of the guide surfaces

do not coincide .

8. A pivot as claimed in claim 5 wherein the frame guide

(23) is engaged with an upstand (26) and is at least in

part thereby restricted from movement relative to the

frame mounting member (10) .

9. A pivot as claimed in any one of claims 3 to 8 wherein

there is included stop means (18, 19a and 20, 21) to limit the extent to which the pivot can move in one

direction.

10. A pivot as claimed in claim 9 wherein the stop means

includes an end surface (18 or 20) of the link arm (12)

engaging with a surface (19a or 21) fixedly located with

the sash mounting member (11) or frame mounting member

(10) .

11. A pivot for the mounting of a window sash and a window

frame, the pivot comprising an elongate frame mounting

member (10) , a sash mounting member (11) , a link arm

(12) pivotally mounted by a first end (12a) to the frame

mounting member (10) and by a second end (12b) to the

sash mounting member (11), a sash guide (22) carried by

the sash mounting member (11) said sash guide (22)

having a sliding surface (29) disposed beyond the second

end of the link arm (12) , said sliding surface (29)

being in sliding contact with a fixed contact surface

(28) which extends across at least part of the width of

the elongate frame mounting member (10) .

12. A pivot as claimed in claim 11 wherein the sliding

surface (29) and contact surface (28) are both of curved

configuration .

13. A pivot as claimed in claim 11 wherein the sliding

surface (29) and contact surface (28) are curved and are

of the same radius of curvature but the centres of radii

of the surfaces do not coincide .

14. A pivot as claimed in claim 11 wherein the contact

surface (28) is formed with a frame guide (23) which is

engaged with a mounting means (26) of the frame mounting

member (10) , said contact surface projecting

substantially normal to a surface of the frame mounting

member (10) and extending substantially at an angle

across the width of the frame mounting member (10) .

15. A pivot as claimed in claim 14 wherein the contact

surface (28) and sliding surface (29) are only partially

in surface to surface contact.

16. A pivot as claimed in claim 15 wherein the contact

surface (28) and sliding surface (29) are curved and are