IE53622B1 - Window assembly - Google Patents

Description

This invention relates to a window assembly comprising a fixed frame, a ventilator sash slidable upwardly from a closed position at the bottom of the fixed frame, and catch means which retains said sash at its upper end in slidable engagement with said fixed frame but which is releasable to permit said sash to be pivoted inwardly about a substantially horizontal axis at its lower end to enable the external glass surface of the sash to be cleaned. Such a window assembly will hereafter be referred to as a window assembly of the kind specified.

It is desirable”that the sash, usually termed a drop back ventilator sash, cannot be capable of being pivoted when it is in its lowermost position. If such pivoting were attempted, the bottom of the sash and the sill part of the fixed frame may be damaged. It has been proposed hitherto that the sash and fixed frame be provided with co-operating fittings which prevent such pivoting when the sash is in its lowermost position, but this entails the provision of separate components which can be unsightly. It is an object of the present invention to provide an improved means for overcoming the risk of damage to the sash.

According to the invention, we provide a window assembly of the kind specified wherein there are provided formations which engage when said sash is in its lowermost position to prevent release of said catoh means.

Preferable said catoh means is mounted on said sash and includes a catoh element which protrudes therefrom to engage a part of the fixed frame to retain said slidable engagement therewith, retraction of said catch element permitting said pivoting of the sash. Said catoh element may then include a recess which is entered by a formation on said fixed frame - 3 53632 when the sash is in its lowermost position, to prevent retraction of the catch element.

By preventing release of the catch means, the invention effectively prevents' pivoting of the sash, and yet does not require the provision of elements additional to the catch means itself.

The invention will now be described by way of example with reference to the accompanying drawings, of which! Figure 1 is a perspective view of part of a sash, illustrating diagrammatioally the invention, Figure 2 is a diagrammatic section through part of a sash and fixed frame assembly incorporating the invention.

Referring to the drawings, there is illustrated part of a window assembly comprising a sash 10 and a fixed frame 11. The fixed frame 11 is made from an extrusion 12 of an aluminium alloy, with a thermally insulating covering 13 and plastics sections 14, 15 clipped to the extrusion 12. In a typical window installation, there would be another sash, but this is not illustrated.

The sash 10 has a frame which is also made from extruded aluminium alloy sections, of which a vertical side member 16 and a horizontal top member 17 are illustrated. Adjacent its lower end, the sash 10 is pivotable in known fashion about a generally horizontal axis, inwardly of the building in which the window assembly is installed to permit cleaning of the exterior glass surface 18 of the sash. Such pivoting is normally resisted by a catch element 19 which engages behind the component 14 of the fixed frame of the window. In Figure 2, the position of the catch element 19 is shown superimposed on the vertical part 16 of the sash frame,· but in fact the catch element is housed within the horizontal member 17.

When pivoting of the sash is required, the catch member 19 can be retracted, against the action of a spring (not shown), by a manually operable sliding member 20. To prevent possible damage to the sash and sill of the window assembly, however, such retraction of the catch element 19 when the sash is in its lowermost position is prevented by a formation constituted by an extended portion 21 of member 14, engaging in a recess 22 in the catch element 19- Only when the sash has been raised above its lowermost position by a safe amount does the catch element clear the formation 21 so that it can be retracted.

The invention thus provides safety against pivoting of the sash when it is in its lowermost position, and yet does not entail the provision of any components in addition to the catch element 19 and the part of the fixed frame of the window assembly with which it engages.

It will be appreciated that in a typical window assembly a further catch will be provided at the opposite end of the horizontal member 17 of the sash. Only one of the catches, and its corresponding part of the fixed frame, need to be provided with the inter-engaging formations which prevent retraction of the catch, but in practice both catches may be so provided so that standard parts can be used.

Claims (3)

1. A window assembly of the kind specified wherein there are provided formations which engage when said sash is in its lowermost position to prevent release of said catch means.

2. A window assembly according to Claim 1 wherein said 5 catch means is mounted on said sash and includes a catch element which protrudes therefrom to engage a part of the fixed frame to retain said slidable engagement therewith, ' pivoting of the sash being permitted by retraction of said catch element, and wherein said catch element includes a •jQ recess which is entered by a formation on said fixed frame when the sash is in its lowermost position to prevent retraction of said catch element.

3. A window assembly substantially as hereinbefore described with reference to and as shown in the accompanying 15 drawings.