GB2260161A - A stay restricting device - Google Patents

Abstract

A restricting device 21 for a stay of the type including a slider 9 mounted in a support track 1 comprises a body portion held by the slider 9 of a stay and being free to turn about an axis through a central region of the body portion. The body portion has a tooth for engagement with the support track 1 of the stay and a release lever attached to the body portion 25 for turning the body portion about the axis to move the tooth between a restricting position, wherein the tooth engages the support track to prevent the slider 9 moving further along the support track 1, and a release position, wherein the tooth is disengaged from the support track 1. <IMAGE>

Description

A RESTRICTING DEVICE This invention relates to restricting devices which limit the opening of a stay, such as a friction stay, and which can be released to allow full opening of the stay.

Stays, such as window friction stays, are well known and have many different configurations. In certain applications, it is important that the opening of a stay be restricted, thereby preventing a vent mounted on the stay from opening fully. This is particularly important where young children have access to the vent, which may be a window. It is likely, however, that the window will have to be opened fully at certain times, such as for cleaning, and therefore the stay cannot be permanently restricted.

In the light of the foregoing, it is sometimes desirable for a window stay to incorporate means for restricting the opening of the window, which means can be overcome to enable the window to be opened fully. Such restricting means are known in the art, but they are in general complicated to manufacture, install and use. The present invention aims to improve upon the prior art and to provide a restricting device which is very simple to manufacture and easy to install, and yet is reliable and efficient in its functional capabilities.

According to the present invention, there is provided a restricting device for a stay of the type including a slider mounted in a support track, the restricting device comprising a body portion adapted to be held by a slider of a stay, the body portion being free to turn about an axis through a central region of the body portion, during use, a first tooth extending from the body portion for engagement with the support track of the stay and a release lever attached to the body portion for turning the body portion about the axis to move the tooth between a restricting position, wherein the tooth engages the support track to prevent the slider moving further along the support track, and a release position, wherein the tooth is disengaged from the support track.Such a restricting device is particularly compact and far more simple to manufacture, install and use than those of the prior art, and yet still provides an efficient and reliable restricting function.

Preferably the body portion is substantially planar and sits within the support track of a friction stay, during use.

The release lever is preferably off-set from the body portion and extends over an edge of the support track, during use.

Preferably the tooth is positioned such that it can only be disengaged from the support track, during use, if the slider is moved backwards from its restricted position.

Although only a small movement of the slider may be necessary, this contributes greatly to preventing young children from releasing the restricting device, especially if there are two stays supporting a window, each with restricting devices.

During use, the body portion may be attached to the slider by a pivot acting through the central region of the body portion, the body portion being free to turn about the pivot axis. Alternatively, the restricting device may be held in position by virtue of the shape of the slider, the body portion being shaped to rotate in co-operation therewith.

Preferably the pivot, if included, is formed integrally with the body portion, the pivot engaging a hole in the slider when installed in a stay. Alternatively, the pivot may be mounted on the slider of the stay and engage a hole in the body portion of the restricting device.

The pivot axis is preferably slightly off-centre with respect to the body portion, the axis being between the centre of the body portion and the tooth. By placing the pivot axis in this position, it is necessary for the slider to be backed-off further to enable the tooth to be released from the support track.

Preferably a second tooth extends from the body portion on the opposite side of the pivot axis to the first tooth such that, when the first tooth engages a side of the support track, during use, the second tooth engages the opposite cide of the support track. By including two teeth which engage opposite sides of the support track, additional strength is provided to prevent movement of the slider and hence opening of the window.

Preferably the body portion includes an indent on its edge for receiving a detent mounted on the slider, the detent entering the indent to hold the restricting device in its release position. This feature enables a user of the restricting device to feel a positive movement between the restricting position of the restricting device and its release position. The detent may be a resilient plastics nib or, alternatively, the pivot may be sufficiently flexible to allow engagement and disengagement of the indent and a rigid detent.

More preferably, the body portion includes a second indent on its edge for receiving the detent mounted on the slider, the detent engaging the second indent when the restricting device is in its restricting position.

The release lever preferably includes a contact region which is designed to interact with a strut of the stay, during use, to re-set the restricting device into its restricting position as the stay is closed. This automatic re-set feature ensures that when the stay is opened from its closed position, it always becomes restricted until the user positively moves the restricting device to its release position by pushing on the release lever.

The or each tooth of the restricting device may be made of steel. The remaining parts of the restricting device may also be made of steel, but other materials could also be used, such as plastics.

A specific embodiment of the present invention is now described, by way example only, with reference to the accompanying drawings, in which: Figure 1 is a plan view of a friction stay incorporating a restricting device according to the present invention; Figure 2 is a plan view of a restricting device according to the present invention; Figure 3 is view from below of a friction slider adapted to receive the restricting device of Figure 2; and Figure 4 is a schematic plan view showing the restricting device, the friction slider and a strut mounted on the slider interacting.

With reference to Figure 1 of the drawings, a friction stay comprises a support track 1, having a bottom 3 and two upstanding sides 5 with inwardly facing flanges 7, a friction slider 9, a vent support arm 11, a fixed link 13, a first link 15, a second link 17 and a support strut 19.

Such a configuration of friction stay is well known in the art.

Figure 1 also shows a restricting device 21 according to the present invention attached to the slider 9 by means of a pivot 23. The pivot 23 is integral with the restricting device 21 and engages a whole in an end of the friction slider 9. The restricting device 21 is able to move along the track 1 as the slider 9 moves.

With reference to Figures 1, 2 and 4, the restricting device 21 comprises a body portion 25 upon which the pivot 23 is formed integrally therewith. The body portion 25 is substantially planar and is shaped to fit within the support track 1 of the friction stay. A first tooth 27 and second tooth 29 extend from opposite edges of the body portion 25 and are shaped to engage the edges of slits (not shown) in the sides 5 of the support track 1 when the restricting device 21 is in it restricting position (as shown in full line in Figure 4).

The restricting device 21 further includes a release lever 31 attached to the body portion 25. The release lever 31 is off-set from the plane of the body portion 25 by means of a shoulder 33, to enable the release lever to extend outside the support track 1 over one of the flanges 7. The release lever 31 includes an enlarged finger-activation area 34 and is preferably formed integrally with the body portion 25, but could also be formed separately and attached thereto.

With reference to Figure 3 of the drawings, a friction slider 9 adapted to receive the restricting device of Figure 2 comprises a stem 35 having upper flanges 37 and lower flanges 39 extending therefrom. The upper flanges 37 overlie the flanges 7 of the support track 1, whereas the lower flanges 39 engage under the flanges 7 of the support track 1 within the support track 1. The slider 9 includes two holes 41 to enable the slider 9 to be attached to the first and second links 15, 17. A friction adjusting screw 43 is provides at one end of the slider 9 and a hole 45, for receiving the pivot 23 of the restricting device 21, is provided at the opposite end of the slider 9. The lower flanges 39 are cut away to define an opening for receiving the restricting device 21.Further, the cut-away portion defines a nib 47 for engagement in a first indent 49 or a second indent 51 formed on the edge of the body portion 25 of the restricting device 21.

During manufacture of the friction stay, the restricting device 21 is simply attached to the slider 9 by passing the pivot 23 through the corresponding hole 45 in the slider 9 before these two components are slid into and along the support track 1. The restricting device 21 is then held in position due to the bottom 3 of the support track 1 preventing the pivot 23 from exiting the hole 45.

With reference to Figure 4, when the friction stay is in its fully closed position, the second link 17 overlies the support track 1 and forces the release lever 31 outwards away from the support track 1. This occurs because the second link 17 bears against the shoulder 33 of the release lever 31. When the release lever 31 is in this position, the two teeth 27, 29 are in their most extended positions and engage in slits (not shown) formed in the sides 5 of the support track 1. At this time, the nib 47 of the slider 9 engages the first indent 49 in the body portion 25 of the restricting device 21. As the friction stay is opened, the slider 9 and restricting device 21 move along the support track 1 with the teeth 27, 29 travelling along the slits.

At a predetermined angle of opening of the vent arm 11, the teeth 27, 29 engage the ends of their respective slits and the slider 9 can move no further. Hence, the friction stay is now in its restricted position.

To enable the stay to open further, the release lever 31 must be pushed inwardly towards the support track 1.

However, due to the engagement of tooth 27 on the end of its respective slit, it is not possible to force the release lever 31 inwardly unless the slider 9 and restricting device 21 are moved backwards slightly towards the closed position of the stay. The tooth 27 is then free to disengage from its slit as the body portion 25 rotates about the pivot 23 due to the release lever 31 being moved inwards. At the same time the tooth 29 disengages from its respective slit on the other side of the support track 1.

In the release position (as shown in dotted lines in figure 4), the nib 47 engages the second indent 51 to hold the restricting device 21 in this position. Further, when in the release position, the teeth 27, 29 have been moved away sufficiently from the side 5 of the support track 1 for the slider 9 and restricting device 21 to move freely along the support track. Thus, the friction stay can be opened fully.

As the friction stay is moved towards its closed position, as mentioned previously, the second strut 17 bears against the shoulder 33 of the release lever 31 and urges the release lever 31 outwards. This occurs when the teeth 27, 29 of the restricting device 21 are adjacent the slits in the sides 5 of the support track 1. Hence, the body portion 25 is able to rotate about the pivot 23 as the release lever 31 is moved outwardly, such that the restricting device 21 automatically takes up its restricting position once again. When this has occurred, the stay cannot be fully opened again until the restricting device 21 is moved back into its release position.

As will be appreciated, the restricting device 21 according to this invention is very simple and compact, and does not require the inclusion of any springs as are often used in the prior art devices. Furthermore, the restricting device 21 can be released relatively easily, assuming that the user knows that the stay must be closed slightly before release can occur, and automatically re-sets itself when the stay closes. The nib 47 is provided primarily to enable a user of the restricting device 21 to feel when the device has moved from its restricting position to its release position as the indent passes the raised portion between the two indents 49, 51.

In the drawings, the pivot 23 is positioned slightly off-centre from the central region of the body portion 25.

Indeed, the pivot 23 is positioned between the centre of the body portion 25 and the first tooth 27 nearest the release lever 31. By positioning the pivot 23 in this way, it is necessary for the slider 9 and restricting device 21 to be backed-off further (in order to release the restricting device 21) than would be the case if the pivot 23 were in the centre of the body portion 25.

As will be appreciated, by positioning the pivot in the central region of the body portion 25, the size of the restricting device 21 is substantially smaller than anything envisaged or used in the prior art. This is a distinct advantage of the present invention.

The whole restricting device 21 may be formed in one piece. Alternatively, since the teeth 27, 29 contact the edges of the slits and wear thereagainst, these alone could be made of a particularly hard-wearing material, such as steel. Other suitable materials could equally well be used.

The present invention has been described in conjunction with a friction stay including a number of struts and links.

However, the restricting device 21 could be used with a number of other devices or hinges which require the motion of a slider along a track to be restricted.

It will of course be understood that the present invention has been described above purely by way of example, and that modifications of detail can be within the scope of the invention.

Claims (17)

1. A restricting device for a stay of the type including a slider mounted in a support track, the restricting device comprising a body portion adapted to be held by a slider of a stay, the body portion being free to turn about an axis through a central region of the body portion, during use, a first tooth extending from the body portion for engagement with the support track of the stay and a release lever attached to the body portion for turning the body portion about the axis to move the tooth between a restricting position, wherein the tooth engages the support track to prevent the slider moving further along the support track, and a release position, wherein the tooth is disengaged from the support track.

2. A device as claimed in claim 1, wherein the body portion is substantially planar and sits within the support track of a friction stay, during use.

3. A device as claimed in claim 1 or claim 2, wherein the tooth is positioned such that it can only be disengaged from the support track, during use, if the slider is moved backwards from its restricted position.

4. A device as claimed in any preceding claim, wherein, during use, the body portion is attached to the slider by a pivot acting through the central region of the body portion, the body portion being free to turn about the pivot axis.

5. A device as claimed in claim 4, wherein the pivot is formed integrally with the body portion, the pivot engaging a hole in the slider when installed in a stay.

6. A device as claimed in any preceding claim, wherein the axis, about which the body portion is free to turn, is slightly off-centre with respect to the body portion, the axis being between the centre of the body portion and the tooth.

7. A device as claimed in any preceding claim, wherein a second tooth extends from the body portion on the opposite side of the axis to the first tooth such that, when the first tooth engages a side of the support track during use, the second tooth engages the opposite side of the support track.

8. A device as claimed in any preceding claim, wherein the release lever is off-set from the body portion and extends over an edge of the support track, during use.

9. A device as claimed in any preceding claim, wherein the body portion includes an indent on its edge for receiving a detent mounted on the slider, the detent entering the indent to hold the restricting device in its release position.

10. A device as claimed in claim 8, wherein the body portion includes a second indent on its edge for receiving the detent mounted on the slider, the detent engaging the second indent when the restricting device is in its restricting position.

11. A device as claimed in any preceding claim, wherein the release lever includes a contact region which is designed to interact with a strut of the stay, during use, to re-set the restricting device into its restricting position as the stay is closed.

12. A device as claimed in any preceding claim, wherein the or each tooth is made of a hard-wearing material, such as steel.

13. A device as claimed in any preceding claim, which is formed in one piece.

14. A restricting device substantially as hereinbefore described with reference to and as shown in Figures 1, 2 and 4 of the accompanying drawings.

15. A slider for a friction stay adapted to receive and interact with a restricting device as claimed in any preceding claim.

16. A friction stay including a restricting device as claimed in any one of claims 1 to 13.

17. A friction stay substantially as hereinbefore described with reference to and as shown in the accompanying drawings.