GB2169953A

GB2169953A - Stays for windows

Info

Publication number: GB2169953A
Application number: GB08601079A
Authority: GB
Inventors: John H T Williams
Original assignee: WEST ALLOY DIECASTINGS
Current assignee: WEST ALLOY DIECASTINGS
Priority date: 1985-01-18
Filing date: 1986-01-17
Publication date: 1986-07-23
Also published as: GB8501356D0; GB2169953B; GB8601079D0

Abstract

A window stay for a caravan window or the like comprises two link arms (1 and 2) pivotally interconnected (at 22) with a pivot interconnection (7a) also to a window fixture (4) and a further pivot interconnection (20) to a fastening device connected with the window frame. The pivot interconnection (7) between the two links (1 and 2) has a roller (24) urged by a spring (26) into contact with undulations (23) carried by a radiused end of link (2) such that pivotal movement is accompanied by an alternate assisting and resisting force. The arrangement enables the stay to be held open in one of a selected number of angular positions including the fully open over centre position shown. <IMAGE>

Description

SPECIFICATION Stays for windows This invention relates to an improved stay chiefly to be used for supporting a window, the stay comprising two links interconnected through the one ends of each link by a common pivot shaft thus allowing angular movement of one link relative to the other.

The opposite ends of each of the links are respective ly and directly or indirectly connected through pivots to a hinged window frame or like construction on one hand and a supporting frame or like construction on the other hand.

In such a stay the links may be pivoted to an open position wherein they are in longitudinal alignment and then beyond to an over-centre position where further pivoting movement is prevented by a stop.

An object of this invention is to provide an improved construction of stay wherein there is controlled resistance to pivotal movement between the two links. A further and preferred object is to provide a construction wherein one link may nest inside the other.

According to this invention there is provided a stay having two link arms pivotally interconnected at their one ends, the other ends of each of the arms being pivotally connected to respective fastening means, the pivotal joint between the arms having means giving controlled and defined resistance to angular motion between the two arms about the joint.

There may be provided, during the initial opening motion, a defined angular movement wherein the resistance to angular motion is minimal.

The means giving controlled and defined resistance to angular motion may comprise detents such as teeth and a means such as a roller or ball engaging therewith.

Preferably the arrangement is such that one link arm folds and nests between two side webs of the other link when the window frame is in the closed position.

Controlled resistance and assistance to angular movement of one link relative to the other link may be provided by a series of teeth on one, preferably the nested, link around the periphery of a radiused end.The radius centre being the same as the common shaft centre; whilst the other, preferably the webbed, link is provided with a recess for housing a compression spring and side guides on the webs for locating each end of a floating roller, allowing movement only along the longitudinal axis of the compression spring so that force can be induced by the compression spring on to the circumferential surface of the roller at a mid point along the length, when the roller is pressed against the spring.

In the mid angular positions (between the fully closed and fully opened positions) the roller engages between the teeth of the nesting link, thus lying between the sides of the valley created by two adjacent teeth. The valley tapers at the base or root to prevent the roller from touching the bottom, thus providing firm and positive location and preventing any slack or free angular movement from taking place.

The tooth profile is designed in such a way that when manually applied angular movement is imparted to one link relative to the other, the roller rides up the tooth producing a gradual decreasing resisting torque until it reaches top level centre, where the torque is at its lowest intensity caused by friction only. Past this point a torque is produced that assists angular movement gradually increasing until the roller is firmly engaged between the walls of the second valley. Continuation of th is manually applied angular movement repeats the cycle a number of times creating a wave effect of alternating resisting and assisting torques each time the roller rides over a tooth.

A construction of an over centre window stay in accordance with this invention is described by way of example with reference to the accompanying drawings: Figure 1 shows a typical in situ arrangement of an over centre window stay in the mid angular position, Figure 2 shows a cross-sectional view of the stay assembly showing the links in the fully open position, Figure 3 shows a plan view of the stay assembly showing the links in the fully open position, Figure 4 shows a cross-sectional view of the stay assembly showing the links in the fully closed position, Figure 5 shows a detail of a quick release attachment of a linkto a window before engagement, Figure 6 shows a detail of the quick release attachment after engagement of the link with the window, Figure 7shows an exploded view of a pin attachment, and Figure 8 shows the pin attachment connected.

Referring firstly to Figure 1 of the drawings this shows a typical installation of window stay according to the invention wherein a window frame unit 101 is pivotally connected at 102 to the side wall 103 of a caravan or the like. The lower side edges of the window have a fixing 104 with a pivot 105 serving to couple a first link 106 with the window. This link is further coupled via a pivot 107 with a second link 108 in turn connected with a further pivot 109 to a mounting bracket 110 attached also to the side wall 103 of the caravan. In the position shown the stay is in the process of opening and when fully opened the links 106 and 108 lie in a position which is just past that of longitudinal alignmentthusgiving an over centre action preventing forces acting on the window 101 from thereafter closing same.To close the window the links 106 and 108 are pivoted so that they "break" whereafter the window may be closed.

Two links can be provided, one on each side of the window.

Referring now to Figures 2, 3 and 4 of the drawings, these show a construction of window stay according to the invention using a first link 1 having at its one end a pivot 7a connecting same with a mounting 4 attached to the window W this link having a further pivot 7 at its other end which connects with one end of a second link 2 having at its other end a pivot 20 connecting with a bracket attached to the side wall of a caravan or the like. The window mounting comprises a part 8 which engages a part 3 including a spigot passing through an aperture in the windowwith the two parts retained together by means of a bolt 6. Washers 5 forming load bearing elements are provided on each side of the window W.The link 1 comprises a base portion with two webs 21 forming a U-shape channel in cross section and the second link 2 is arranged so that it may be received within the channel when fully folded as illustrated in Figure 4. The end 22 of link 2 is rounded with a radius of curvature centred on the pivot axis 7 and this end is further provided with a series of undulations 23 forming detents in the nature of teeth. The undulations 23 are engaged by means of a roller 24 movable within a recess 25 on the base of the link 1,the roller being forced into engagement with the undulations 23 by means of spring 26. The roller and spring assembly 24, 26 is trapped when the link 2 is assembled to the link 1, these two links being retained by the common pivot pin 7.With this arrangement and in the position shown in Figure 2, the link 2 abuts the edge 27 of the link 1 and a force exists holding the link in this position by virtue of roller 24 acting on the inclined surface of the tooth 28 being the first in the series of teeth forming the undulations 23. As the link arm 2 is pivoted an increasing force is required to deflect the roller 24 until same lies on the apex of tooth 28 whereafter an assistance to the pivoting movement is provided through the roller 24 moving down the opposite inclined surface until it lies within the valley formed between the tooth 28 and tooth 29. It will be appreciated that the spring 26 assists the movement in this phase and there is thereafter resistance to movement as the roller again rides up the flank of the adjacent tooth 29.This arrangement thus, produces a series of alternating resisting and assisting forces during the closing movement of the link 2.

On the other hand in the fully closed position shown in Figure 4the roller 24 lies on a side surface of the link 2 and there thus exists a certain free angular movement before the roller meets the inclined ramp surface of the tooth 30. By this means entry and exit to and from the resting closed position is obtainable with a minimal resisting torque. The end of link 1 having the pivot 7 is profiled so as to form a toggle 31 to enable the stay to be manually opened or closed. The pivot 7 connecting link 1 to the window attachment 4 comprises a pin 32 which in this embodiment, is non-detachable. A similar pin (not shown) may form the pivot 20 and passes tough the bifurcated end 33 of the arm 2.

In an alternative construction shown in Figures 5 and 6 the attachment pin 7 on the end of the link arm 1 is arranged to engage a recess 50 which is formed by an extension 51 of the end fitting 8. This extension is curved and has a catch member 52 whereby the part may be flexed to open up the recess 50 sufficiently to enable the pin 7 to be engaged or disengaged therewith. In the engaging position the pin 7 may be pressed into the recess 50 which deforms to thereafter snap back thus forming an easy means of connection. Force applied to the portion 52 enables the pivot 7 to be disengaged and thus released in a simple manner.

In a further arrangement shown in Figures 7 and 8 a pin 70 is provided which passes through the apertured end 71 of arm 1. The window fixing 4 includes a correspondingly apertured part 72 and the pin 70 further includes waisted portions 73 which are arranged to provide an interlocking fit when the stay is under load. The pin 70 may be withdrawn by applying a force to the end 74 only when loading is removed from the two parts engaged thereby.

This arrangement therefore provides an over centre window stay which has a controlled resisting and assisting torque built into the assembly so that the torque fluctuates at defined intervals between the fully closed and fully open positions whereby various degrees of opening angle for the window can be obtained whilst full movement of the window is still available without actuating any release latches or the like. A further feature of the construction is the quick release pin or latch which enables the stay to be disengaged from the window completely in a simple manner. The resisting torque is arranged so that light or moderate winds or accidental contact are resisted without angular movement occurring between the window and the frame but the torque is sufficiently low so that it may be moved by manual force or should a heavier impact occur.

Claims

1. A stay for a window or the like opening member, the stay having two link arms pivotally interconnected at their one ends, the other ends of each of the arms being pivotally connected to respective fastening means, the pivotal joint between the arms having means giving controlled and defined resistance to angular motion between the two arms about the joint.

2. A stay in accordance with Claim 1 wherein during the initial opening movement of the arms there is provided a defined angular movement wherein resistance to angular motion is minimal.

3. A stay in accordance with Claim 1 or 2 wherein one link arm nests within the other link arm when the two arms are in the closed position, the arms being able to pivotally move to an open position through an angle exceeding 1800 and to thereafter come into abutment to form an over centre lock.

4. A stay in accordance with any preceding claim wherein the means giving controlled and defined resistance to angular motion comprises a plurality of detents on one of the link arms and a means engaging said detents on the other link arm.

5. A stay in accordance with Claim 4 wherein the detents comprise a series of teeth positioned concentrically about the pivotal joint between the arms.

6. A stay in accordance with Claim 4 or 5 wherein the means engaging the detents comprises a roller or ball urged into contact therewith by spring means.

7. A stay in accordance with Claim 6 wherein the roller or ball is housed together with the spring in a cylindrical recess provided in the link arm.

8. A stay in accordance with any preceding Claim wherein the means connecting one link arm to a fastening means includes a releasable pivotal coupling formed by a pin.

9. A stay in accordance with any preceding Claim 1 to 7 wherein the means connecting one link arm to the fastening means comprises a pin engaging a slot with a snap action.

10. A stay for a window or the like substantially as herein described and as illustrated in Figures 2, 3 and 4 of the accompanying drawings.

11. A means for releasably engaging a window stay with a window fixture substantially as herein described with reference to Figures 5 and 6 or 7 and 8 of the accompanying drawings.