This invention relates to a handle mounting assembly for a vent or casement window.

When transporting pre-assembl ed uPVC profile window frames from a manufacturer to the point of installation, the frames are preferably stacked side-by-side or one on top of the other. A problem which then arises is that projecting parts of the frame, such as closure handles, may cause damage or may themselves be damaged during transit. One way to overcome this problem is to fit the handle on site.. At present, this would involve the site personnel carrying the necessary fastening components, and would further add to the time and cost of installation. Moreover, the fastenings would be visible after fitting the handle, and some means would be required for temporarily holding vent or casement windows shut during transit.

Accordingly, there is a need for a handle which can be easily fitted to a window after installation without the need for additional fastening components and without any such components being visible.

In GB-A-1439606 there is disclosed a handle mounting assembly in which a mounting plate pivotally secured to a handle is detachably secured to a fixing plate secured to the window frame. In this arrangement, the mounting plate slidably engages the fixing plate, and the two plates are

held together by a wedging action and by a screw which remains visible after the fixing has been completed. The handle can be removed by withdrawing the screw and pulling the two plates apart. In addition, no means are provided for temporarily securing the window during transit.

According to the present invention there is provided a handle mounting assembly for a vent or casement window, the assembly comprising a first mounting member secured at one end of a lever handle, and a second mounting member secured to the window frame, the f rst member being engageable with the second member to mount the handle on the frame, characterised in that the two mounting members have cooperating parts which interlock with one another when the first member moves into engagement with the second member, the interlock being such that the two members cannot be separated.

In a preferred embodiment the first mounting member, when engaged with the second mounting member, conceals the fixing of the second member to the window frame. Preferably, the first member is slidably engageable with the second member, and the interlock includes a resilient catch mechanism preventing return sliding movement in the opposite direction.

In one form of handle assembly embodying the invention, a

wedge stop secured to a fixed window frame bounding the vent or casement without is initially joined to the second mounting member by a severable link to hold the window closed prior to mounting the handle. After severing the link and mounting the handle, the wedge stop is adapted to progressively engage a projection of the handle to secure the window when the handle is pivoted to its closed posit ion.

The joining link and wedge stop are preferably made of a plastics material and moulded in one piece with an insert that fits in the second mounting member.

By way of example only, an embodiment of the invention is illustrated in the accompanying drawings in which

Fig. 1 is a diagrammatic perspective view of a handle mounting assembly for a vent window,

Fig. 2 is a plan view of the insert, joining strip and wedge shown in Fig. 1,

Fig. 3 is a longitudinal section through the handle mount ing unit ,

Fig. 4. is a side elevation of an insert for a mounting block,

Fig. 5 is a side elevation of the mounting block,

Fig. 6 is a diagrammatic perspective view of a mounting assembly for one alternative handle, and

Fig. 7 is a diagrammatic perspective view of a mounting assembly for another alternative handle.

Referring first to Figs. 1-5 of these drawings, there is shown a Cockspur handle 13 for closing a vent window frame 10 against a fixed frame 20.

The frames 10, 20 are pre-assembled uPVC frames which are delivered to the site of a building without the handle 13 being fitted. During transit, the window is held closed by a severable link 17 between a wedge stop 14 secured to the fixed frame 20 and an insert 16 snap-fitted in a mounting block 11 secured to the vent frame 10. At the site, the link 17 is severed and the handle 13 is mounted on the mounting block.

The mounting block 11 (Fig. 5) comprises a fixing plate 18 and a platform 19 offset toward one end of the fixing plate. The fixing plate is secured to the vent frame 10 by screws or rivets 30 (Fig. 1) passing through three longitudinally spaced holes 22.

The top surface of the platform 19 is recessed at 31 to receive an insert 16 shown enlarged in Fig. 4. The insert 16 has downwardly projecting pins 41 which snap-fit in holes 21 formed in the mounting block 11.

The top surface of the insert 16 includes a series of serrations 29 which co-operate with corresponding serrations 27 in the interior roof surface of a generally dome-shaped handle mounting unit 12 (Fig. 3) secured to the handle 13, the serrations 27,29 forming a catch mechanism preventing return movemet when the unit 12 slidably engages the block 11.

The handle mounting unit 12 comprises an elongate generally dome-shaped housing 23 with a top wall 32, a pair of opposed side walls 33, and opposed end walls 34a,34b. The top wall 32 has two bores 24,26, the bore 24 passing through the top wall and receiving a spindle (not shown) projecting from the handle 13, the spindle being swaged over in the cavity 24a such that it can rotate when the handle is turned but cannot be withdrawn from the mounting unit. The bore 26 receives a locking pin 35 to prevent rotation of the handle when the pin is depressed against a spring bias and locked.

Projecting inwardly from the side walls 33 are three longitudinally spaced lugs 28 which slidably locate beneath

overhanging portions 36 of the platform 19 when the handle mounting 12 is slidably interlocked with the mounting block 11.

In use, with the handle mounting unit 12 interlocked with the mounting block 11, the handle 13 can be turned to bring the projection 37 into engagement with the wedge stop 14 so that the wedge is progressively inserted beneath the projection to secure the window.

Before despatching a window for installat on, the original manufacturer will drill fixing holes in the frames 10,20 using a jig. The fixing plate 18 is then riveted or screwed to the vent frame 10, and the wedge 14 is snapped into position on the outer frame 20 by means of locating pins 38 beneath the wedge 14. The insert 16 joined to the wedge 14 by the joining strip 17 is then snap-fitted in the mounting block 11. This retains the window shut during transit to the site where the window is to be installed. The insert/joining strip 16,17 can be undipped from the mounting block 11 to permit inspection of the window before and/or after transporting the window to the site.

At the site, the joining strip 17 is severed and removed. The handle 13 is then fitted by engaging the handle mounting unit 12 with the mounting block 11. This is achieved by initially positioning the inside surface of the

end wall 34a of the handle mounting unit so that it abuts the left hand end of the platform 19 (as viewed in Fig. 5), and then sliding the handle mounting unit 12 to the left. During this sliding motion, the serrations 27 on the inside surface of the handle mounting unit 12 are flexed and slide over the serrations 29, the serrations 27,29 then co¬ operating to provide abutting surfaces which prevent return movement of the handle mounting in the opposite direction. At the same time, the lugs 28 at the base of the housing 23 slide beneath the overhanging portions 36 (Fig. 1) of the platform 19 and thereby prevent the handle mounting 12 being lifted off the mounting block. When the inside surface of the end wall 34b eventually abuts the right hand end of the platform 19 (as viewed in Fig. 5), the handle mounting unit 12 is fully engaged with the mounting block 11 and no further movement of the handle mounting 12 is possible in any direction. The handle 13 can then be operated to open and close the window.

A feature of the handle mounting is that, with the mounting unit 12 fully engaged with the mounting block 11, the screws 30 fixing the plate 18 to the vent frame 10 are concealed. No unsightly fixing devices are therefore visible in the final assembly.

Referring to Figs. 6 and 7, a similar mounting block 11 can be used for mounting other types of handle, such as

Espagnolette and tiIt-and-turn handle, provided these handles are fitted with similar handle mounting units 12 which interlock with the mounting block 11 in the same way.

However, since these handles have a different locking action which does not require the use of a wedge on the fixed frame, the wedge and joining strip 14,17 are omitted and the insert 16 is not necessarily removable from the mounting block 11. During transit, the window is retained shut by operating the conventional locking mechanism associated with these handles using a transit key 40 having a spindle 50 corresponding to that of the respective

Espagnolette 51 or tilt-and-turn 52 handle.

The fixing of an Espagnolette handle 51 is shown in Fig. 6, and the fixing of a tilt-and-turn handle 52 is shown in Fig. 7. In these two figures the same reference numerals have been used to denote like parts as in Figs. 1-5. A C-spanner 54 is additionally provided for engaging the locking collar/spindle assembly 55 of the Espagnolette and tilt-and-turn handles.

Apart from the absence of the wedge and joining strip, the main differences are the different locking actions of the handles which are already known and therefore not described in detail. It will also be noted that the mounting block for the tilt-and-turn handle has two inserts 16a, 16b instead of a single insert. In this case the interior roof

surface of the housing 23 forming the handle mounting 12 will have similar pairs of serrations 27 for co-operating with the respective inserts.