The present invention relates to a window frame com- prising a first frame and a second frame for insertion in an opening in a wall from either side of the wall, in parti¬ cular a wall of sandwich-type with plane front and back pa¬ nels, and in which the frame parts comprise a section cover¬ ing part of the front and back panel along the opening, and a lip adapted to abut on a window pane secured between the first and the second frame part by means of the lips, and in which the first frame part has toothed tongues adapted to lockingly engage pockets in the second frame part, said pockets being provided with locking means for the toothing of the tongues.

WO Publication No. 90/12187 discloses a window frame manufactured by injection moulding from plastics. The window frame comprises a first and a second frame part to be in¬ serted in the opening of a wall from either side, the first frame part having a number of toothed tongues fitting into a corresponding number of pockets in the second frame part. At the insertion the toothing is interlocked in the pockets and the first and second frame parts are then an integral unit establishing the connection between the window pane and the wall. Injection moulding of the frame parts offers great ad¬ vantages from a production point of view in respect of time consumption at the manufacture in comparison with assembly of frames from extruded profiles, but also entails consider¬ able costs in respect of the mnaufacture of the moulds used for the injection moulding. For the manufacture of the known window frame different moulds are to be used for making the first and the second frame parts. If window frames of diffe¬ rent sizes or otherways different shape and equipment are required, the costs for moulds will be very considerable. It is an object of the invention to reduce these costs, for instance halving them.

The window frame according to the invention is cha¬ racteristic by the subject matter of the characterizing

clause of claim 1. By placing the tongues and the pockets as stated, a first frame part can be used as a second frame part provided it is turned 180° and inserted in a corre¬ sponding, not turned frame part. The window frame can there- fore be composed by two identical frame parts if desired, or the frame parts may be manufactured in two variants only differing from each other for instance in appearance in those sections which overlap the edges of the wall, the mould parts shaping these sections being exchangeable inser- tions in the moulds for the injection moulding.

The use of exchangeable insertions in the moulds for injection moulding which are besides used for the manufac¬ ture of both the first and the second frame parts may also include the shaping of the lips abutting against the pane element. Thereby, according to the invention an increased number of variants of the window frame is made possible without the costs of making the moulds increasing propor¬ tionally with the number of variants.

In the preferred embodiment according to the inven- tion the first frame part is identical with the second frame part.

The invention will be described in detail in the fol¬ lowing with reference to the drawing, in which

Fig. 1 is a perspective view of a frame part for a rectangular window frame according to the invention,

Figs. 2a and 2b show a section through a pair of frame parts placed opposite to each other before assembly and the frame parts in section after assembly around a sand¬ wich-wall and with a pane element inserted, resepctively, and

Figs. 3a and 3b show sections corresponding to the sections according to Figs. 2a and 2b, but in an embodiment intended for insertion in a traditional double-glazed pane element. The frame part 1 shown in Fig. 1 is adapted to be connected with a corresponding frame part for the formation of a window frame which fixedly holds a pane element in re¬ lation to a throughgoing opening in a wall, preferably a

wall of sandwich-type with plane front and back panels. The frame part is made integrally from plastics by injection moulding, but comprises four side pieces of essentially si¬ milar and constant profile. The profile comprises a section 2 adapted to extend somewhat over the edge of the wall, in which the window frame is to be mounted. Moreover, the frame part comprises a reinforcing rib 3 serving as anchoring for the connection means, by means of which the two frame parts are mutually connected and for distribution of the tensions deriving therefrom. For the fixation of the pane element between the two frame parts, each frame part is provided with a lip 4, which with its edge 5 directed towards the centre of the frame part is adapted to sealingly and resi- liently abut on the pane element. The lip 4, therefore, forms an angle of for instance approx. 60° with the section 2. The connection means consist of tongues 6 which on one or more side faces are provided with a toothing 7 as well as of pockets 8 having a guiding slot 9, the clearance of which essentially corresponds to the cross-section of the tongue 6. In the opening 9 a kind of latch (not shown in Fig. 1) is mounted. The latch cooperates with the toothing 7 and has the effect that the tongue 6 after insertion in the opening 9 cannot be pulled out again. It will be seen from Fig. 1 that the tongues 6 and the pockets 8 are placed with sub- stantially uniform interspaces along the reinforcing rib 2 and in such a way that a tongue 6 and a pocket 8 are placed alternately. The arrrange ent is further symmetrical around one of the symmetry axes 10 of the frame part 1, however, in such a way that symmetrically opposite to each tongue a pocket 8 is provided. By this arrangement a window frame can be assembled by means of two identical frame parts 1 pro¬ vided that one of them is turned 180° in relation to the other.

Fig. 2a is a sectional view through two frame parts 1 and l ¹ placed opposite to each other before assembly. The frame parts 1 and l ¹ are identical, but they have been turned in relation to each other in such a way that a tongue 6 is placed exactly opposite to a pocket 8'. It will be

seen, that the frame parts comprise a section 2 adapted to cover the edge of the wall, in which the frame is to be in¬ serted, and a lip 4 with a sharp edge 5 which may sealingly abut on the pane element. Behind the edge of the section 2 a rib 11 is provided, said rib being adapted to limit the squeezing out of a string of sealing substance, which may be placed on the inner face of the section 2 before the assemb¬ ly of the frame parts 1,1'. The lip 4 is likewise provided with an interior rib 12, which may serve as an extra sealing or as guide for a string of sealing substance at the assemb¬ ly. Fig. 2b shows the frame parts 1 and l ¹ after the assemb¬ ly. The pane element is a double-glazed pane of the type, in which the two layers of glass or acrylics abut on each other along the edge. Figs. 3a and 3 b show corresponding embodiments of frame parts adapted to be used in connection with conven¬ tional double-glazed panes with two layers of plane glass. The frame parts are identical with the frame parts according to Fig. 2a apart from the shape of the lips 4", said plips being smaller and running substantially parallel with the sections 2" covering the edge of the wall in the window opening.

The frame parts 1 are made by injection moulding from a suitable plastics, for instance ABS, which are di ension- ally stable and weather-resistant. It will be seen that the frame parts according to Figs. 2a and 3a are identical apart from the lips abutting on the pane element. Therefore, the frame parts can be made in the same mould; they only have to be provided with various insertions for forming the lips. The arrangement of letting the window frame comprise two identical frame parts, which by modest changes can be pro¬ duced in two variants, entails a considerable reduction of the costs of making the moulds used for the injection mould¬ ing. The window frame shown in Fig. 1 is rectangular, but the principle may also be used in connection with window frames of other outlines, for instance hexagonal or oval frames, or frames which are rectangular with rounded corners.