GB2318384A - Sash window:motor drive - Google Patents

Abstract

One or both vertically-sliding sash windows 1, 2 may be driven by a motor via a winch and a cable 5 or via a rack and pinion. The motor and winch may be located in a housing in the window frame. The motor may be remotely controlled, and by sensors detecting the end points of window movement.

Description

SASH APPARATUS DESCRIPTION The present invention relates to sliding sash apparatus and is particularly, but not exclusively, concerned with such apparatus for operating a vertically slidable window sash.

As is well known, traditional sash windows comprise a pair of sashes either or both of which is or are vertically slidable within a surrounding frame.

One or both of the sashes may be connected, at each vertical side thereof, to a respective sash cord which runs over an associated pulley to a counterbalance weight housed within a hollow side member of the frame. An alternative to the counterbalance weight is the provision of a spring. The purpose of the counterbalance weight or spring is to enable the sash(es) to be opened to a desired position of opening relative to the frame and to be retained thereat without the provision of any special retaining means.

This traditional form of sliding sash window suffers from a number of disadvantages. Firstly, the raising and lowering of the sash(es) requires manual effort for which there is no alternative. Despite the provision of the counterbalance mechanism, the required manual effort may be considerable in some circumstances, for example if the window has remained unused for a considerable period of time or if the woodwork has become wetted and swollen as a result.

The pulley(s) may not rotate smoothly and may be prone to squeaking. The sash cords are commonly provided by appropriate lengths of rope and are also inclined to rot. Counterbalance weights, where used, may not ride smoothly up and down within the hollow side frame member, whilst counterbalance springs are inclined to make creaking noises as they expand and contract in operation. Unless a separate mechanism is provided for locking the or each sash in a desired open position, it will be held in such position solely by the counterbalancing effect of the weight(s) or spring(s), and, thus, may readily be moved from such position to a wider open position from externally of a building. This presents an obvious security risk.

The present invention aims to provide slidable sash apparatus which eliminates, or substantially reduces, the disadvantages of the traditional sliding sash windows.

According to the present invention, sash apparatus comprises a window sash slidable vertically within a surrounding fixed frame and a motor arranged, when activated, to cause the sash to slide with respect to the frame.

In one embodiment of the present invention, the motor is arranged to drive the window sash directly.

This may be through the medium of appropriate tooth gearing or, alternatively, a flexible operating member.

In another embodiment of the present invention, the motor is arranged to drive the window sash indirectly by means of a flexible operating member which passes over a suitable guide and transmission member.

Where, in either embodiment of the present invention, the motor is arranged to operate the window sash via a flexible operating member, the motor is associated with a rotatable winch drum on to and from which the flexible operating member may be paid in or out.

In any event, the flexible operating member is made of any suitable material, such as stainless steel, in which case, it may be in the form of a stainless steel cord or rope.

The motor, and, where provided, the winch drum, is/are locatable or located within a suitable housing provided within the sash frame. Sensors may be provided to detect the end points of sliding movement of the window sash to stop the motor automatically.

The motor may be activated directly or by remote control.

The present invention will now be described in greater detail, and by way of example only, in the following description of embodiments of sash apparatus, which is given with reference to the accompanying diagrammatic drawings in which: Figure 1 shows an embodiment of the present invention in which a motor operates on a window sash indirectly; and Figures 2 and 3 show different arrangements of an embodiment of the present invention in which the motor operates a window sash directly.

As seen in Figures 1, 2 and 3 of the drawings, slidable sash window apparatus comprises an upper window sash 1 and lower window sash 2 individually and separately vertically slidable within a surrounding frame generally indicated at 3 in a manner which is well known in the art.

The frame 3 comprises respective left hand and right hand frame parts 33, 3b, a top part 3c and a window sill 3d.

In accordance with the present invention, an electric motor is provided for the purpose of operating a window sash and, in the present embodiment, is associated with a rotatable winch drum to form a unit 4 which is housed within part of the window frame 3. A flexible operating member 5, which is preferably in the form of a stainless steel cord, extends from the winch drum unit 4 to a connection point 6 on the window sash 1 and/or 2. During rotation of the winch drum by the motor, the flexible operating member 5 will be either paid on to or paid out from the winch drum depending upon its direction of rotation. Accordingly, the window sash 1 and/or 2 will be either raised or lowered.

In the arrangements shown in Figures 1 and 3, it is the upper window sash 1 to which the flexible operating member 5 is connected, for the purpose of slidably moving that sash 1 between its uppermost, closed condition (as shown), and a lowered, at least partially open condition in which it will be retained automatically by the unit 4 described. If desired, the flexible operating member 5 may be connected, additionally or alternatively, to the lower window sash 2 in order to drive it slidably between its lowered, closed condition (as shown), and a raised, at least partially open condition in which it can be retained. If desired, both the upper and lower window sashes 1, 2 may be so-operable.

In the arrangement shown in Figure 1, the window frame part 3b is a box frame in which the motor-winch unit 4 and flexible operating member 5 are housed. A suitable aperture (not shown) is provided in an upper region of this box frame 3b for passage therethrough of the operating member 5 and, within the box frame 3b and adjacent the aperture, there is provided a suitable guide and drive transmission means (not shown), for example a pulley, over which the flexible operating member 5 is entrained. In this arrangement the window sash 1, 2 is, therefore, operable indirectly by the motor-winch unit 4.

In the arrangement shown in Figure 2, the top window frame part 3c forms of a top box in which the motor-winch unit 4 is housed and from which the flexible operating member 5 passes directly, that is without passage over any form of guide and drive transmission means, such as the pulley of Figure 1, to the connection point 6 of the upper window sash 1.

In the arrangement of Figure 3, the motor-winch unit 4 is housed within an upper region of the window frame part 3b and the flexible operating member 5 again passes directly therefrom to its connection point 6 on the upper window sash 1.

In an alternative embodiment (not shown) of sash apparatus of the present invention, the flexible operating member, as described in the foregoing embodiment, is dispensed with, as is the rotatable winch drum. Instead, the motor is arranged to rotate a toothed element, such as a pinion or worm wheel, which is so-disposed as to contact and engage a toothed element, such as a toothed rack, provided on an edge of the window sash 1, 2. In this case, rotation of the toothed element by the motor is translated into vertical sliding motion of the window sash 1, 2, the direction of such motion depending on the direction of rotation of the motor. In this embodiment, the motor may be housed in either a side box frame part of the window frame or a top box part of the window frame, such that the toothed element to be driven thereby may be housed within a suitable cavity in a side frame part of the window frame. The rotatable toothed element can project through an aperture in the side frame part of the window frame, in order to engage the associated toothed element on the window sash 1, 2. The rotatable toothed element may be mounted directly on the rotatable spindle of the motor or may be connected thereto by suitable gearing, for example, toothed gearing.

In the present invention, the motor, or motors in the case of both sashes 1, 2 being driven, may be operated directly by the provision of manual "open" and "close" electrical switches which may be sited on or adjacent the window frame, or elsewhere, as desired by a user. Alternatively, a remote control handset may be provided and the motor may be associated with an appropriate sensor for sensing signals transmitted from the handset for the purpose of activating the motor in the desired manner.

The or each motor used in the sliding window gear of the present invention will have a maximum weight lifting capacity selected to cope with the demand which arises when raising or lowering its associated window sash, and if desired, a limit of lifting capacity lower than this available maximum may be preset.

Suitable detectors may be provided in the apparatus of the present invention for the purpose of stopping the motor when its associated slidable window sash reaches the respective end points of its allowable motion within the surrounding window frame.

These detectors may be constituted by respective microswitches positioned to detect directly the end points of motion of the window sash 1, 2, or to detect such end points indirectly, for example, by reference to the length of flexible operating member paid out or paid in, or by some other means which will readily be apparent to those skilled in the art. Alternatively, the detectors may be directly associated with the motor and may be arranged to sense significant changes in resistance to rotation of the motor for the purpose of controlling the same. In the case of the upper window sash 1 being driven from the motor, one such detector will sense an increased resistance when the sash 1 reaches its fully raised position in which it abuts the top frame part 3c of the window frame, and another such detector will sense decreased resistance when the sash 1 reaches its lowermost position at which it abuts the window sill 3d.

If desired, means may be provided in order to enable regulation, or adjustment, to the speed of raising and/or lowering of the window sash 1, 2 by appropriate regulation or adjustment of the motor or its electrical supply.

Again, if desired, and for safety reasons, a manually operable emergency cut-out may be provided to enable immediate deactivation of the motor should any emergency arise during its operation to raise or lower the window sash 1, 2. Additionally or alternatively, one or more automatic cut-out devices may be provided to shut off the motor immediately in emergency situations. Thus, for example, should the presence of an intruding object or person interfere with the opening or closing of the window sash 1 2, the motor would automatically be stopped immediately in order to prevent any injury and in order to protect the motor and its associated drive gear from damage.

In that embodiment of the present invention in which the flexible operating member is dispensed with and drive is transmitted directly from the motor to the window sash 1, 2 by way of interengaged toothed elements, the arrangement may be such that any attempt to move the window sash 1, 2 by manual effort applied thereto will be blocked, this affording an increased measure of security against the sash being forced from the outside. Such blocking may be afforded by the gearing ratio of the toothed elements. If desired, additional or alternative, security measures may be applied in order to prevent the window sash(es) 1, 2 from being forced open manually.

Whilst the apparatus of the present invention has been described hereinabove in relation to its currently preferred embodiments, the scope of the present invention is not to be limited thereto, but is to extend to all such variants as fall within the scope of the broadest statement contained herein of the present invention.

Claims (13)

1. Sash apparatus comprising a window sash slidable vertically within a surrounding fixed frame and a motor arranged, when activated, to cause the sash to slide with respect to the frame.

2. Apparatus according to claim 1, wherein the motor is arranged to drive the window sash directly.

3. Apparatus according to claim 2, wherein the motor is arranged to drive the window sash through the medium of toothed gearing.

4. Apparatus according to claim 2, wherein the motor is arranged to drive a flexible operating member.

5. Apparatus according to claim 1, wherein the motor is arranged to drive the window sash indirectly by means of a flexible operating member which passes over a suitable guide and transmission member.

6. Apparatus according to claim 4 or 5, wherein the motor is associated with a rotatable winch drum on to and from which the flexible operating member can be paid in or out.

7. Apparatus according to claim 4, 5 or 6, wherein the flexible operating member is made of stainless steel.

8. Apparatus according to any of claims 4 to 7, wherein the flexible operating member is in the form of a stainless steel cord or rope.

9. Apparatus according to any preceding claim, wherein the motor is locatable or located within a housing provided within the sash frame.

10. Apparatus according to claim 6 or any of claims 7 to 9 when dependent upon claim 6, wherein the rotatable winch drum is located or locatable within a or the housing, as the case may be, provided within the sash frame.

11. Apparatus according to any preceding claim including sensors arranged to detect the end points of sliding movement of the window sash to stop the motor automatically.

12. Apparatus according to any preceding claim, wherein the motor can be activated directly or by remote control.

13. Sash apparatus substantially as hereinbefore described with reference to the accompanying drawings.