GB1604639A

GB1604639A - Metal frames

Info

Publication number: GB1604639A
Application number: GB2682377A
Authority: GB
Original assignee: ROMFORD ALUMINIUM PRODUCTS Ltd
Current assignee: ROMFORD ALUMINIUM PRODUCTS Ltd
Priority date: 1978-05-31
Filing date: 1978-05-31
Publication date: 1981-12-09

Description

(54) METAL FRAMES (71) We, ROMFORD ALUMINIUM PRODUCTS LIMITED, a British Company of 149, North Street, Romford, Essex, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to the joining of metal extrusions, especially for the manufacture therefrom of metal frames. The invention also relates to window frames, especially window frames for double glazing systems.

It is known to manufacture window frames from aluminium extrusions, and in practice the aluminium is extruded in substantial lengths, which are subsequently cut, mitred or otherwise turned into window frames. Aluminium extrusions are also used in the manufacture of double glazing systems, and it is known in such a context to form frames from two separate extrusions or profiles, which are formed separately and subsequently unite. One known method of uniting these separately formed extrusions is by clamping the two extrusions together and pouring into a channel formed between them a castable plastics material which solidifies and holds the extrusions together. One or more surfaces of the cast material are then machined to give a smooth surface.

This cast jointing material can provide what is known as a "thermal break", which is a thermal insulation material placed between the inner and outer skins of the double glazing frame, to minimize or prevent condensation forming on the inner skin of the frame. Such condensation would otherwise appear on the inside of the window and cause obvious problems.

It is an object of the present invention to provide a means for joining two component lengths of a composite strip of extruded metal.

It is a further object of the invention to provide a window frame for a double glazing system.

According to one aspect of the invention, there is provided a composite strip formed of two lengths of extruded metal wherein each length is provided with a longitudinally ex tending channel, held together solely by a pre-formed strip of synthetic plastics material retained in each channel by opposed longi tudinal flanges extending from the sides of the channels each engaging in longitudinal grooves formed in the plastics strip.

The synthetic plastics material is preferably one which has thermal insulating properties, so that it can act as a "thermal break." That sold by Imperial Chemical Industries Limited under the trade designation R7/622 (a grade of PVC) is especially suitable.

The invention also provides a window frame for a double glazing system, which is formed from the composite strip. The extruded metal lengths provide outer and inner frame surfaces respectively and the strip of synthetic plastics material, suitably thermal insulation material, is preferably disposed nearer to the inner frame surface than to the outer frame surface.

It is usual in those double glazing systems used nowadays which incorporate a "thermal break" for the "thermal break" to be disposed towards the outside of the double-skin frame, i.e. adjacent the outer frame surface. This has the effect, in simple terms, of preventing the transmission of cold from outside the window to the inside of the room in which the window is situated. By piacing the "thermal break" adjacent the inner surface of the frame, heat is prevented from passing from the inside of the room to the outside.

The strip of synthetic plastics material, for use in forming the composite strip and the window frame, is preferably extruded and has a cross-section in the form of a Greek cross in which the extremities of two opposed limbs are extended at right angles to form grooves bounded by the extensions and the other two limbs.

A particularly strong and efficient seal between the frame members can be achieved when the bases of the grooves of the synthetic strip, are formed at an angle, e.g. of the order of 30 , to the two said opposed limbs of the cross In forming the composite strip of the invention, the plastics strip will be slidden along the channel of one of the metal extrusions, whereupon the other extrusion is slidden over the plastics strip. Alternatively, the two metal extrusions may be placed with their channels facing each other and the plastics strip pushed into the two channels simultaneously.

In the drawings accompanying the Pro visional Specification and the accompanying drawings, which illustrate the invention, Figure 1 is an elevation, partly cut away and in section, of a corner of a double-glazing window frame in accordance with the invention; Figure 2 is a cross-section of the plastics strip of Figure 1, on a larger scale; Figure 3 is a schematic view showing a fanlight in a window frame, in both open and closed positions; Figure 4 is a cross-section of another form of plastics strip; and Figure 5 shows the profile of a modified outer frame member, to be used in conjunction with a strip such as that of Figure 4.

The window frame 1 comprises an inner frame 2 and an outer frame 3 joined together by a strip of plastics material 4. The metal strip forming inner frame 2 and that forming outer frame 3 are extruded separately, are joined together by means of the plastics strip 4, and are then cut and mitred and formed into conventional rectangular shape.

The inner frame 2 is provided with a longitudinal channel 5 formed by upper and lower arms 6, 7, which arms have inwardly directed flanges 8, 9 respectively.

Outer frame 3 is formed with a similar channel 10. The plastics strip 4 (see Figure 2) is basically of Greek cross section, but each of its horizontal limbs, 11, 12, is provided with extensions at its extremities which form longitudinal grooves lia, lib, 12a and 12b. It will be seen that flanges 8 and 9 engage in grooves 1 lea and 1 Ib respectively, and the flanges of channel 10 are similarly engaged in grooves 12a and 12b.

In order to ensure that metal extrusions 2 and 3 are firmly held together pressure can be exerted on the composite strip, suitably by opposed rollers, in the directions shown by the arrows in Figure 1. It will be normal practice, in assembling the composite metal strip, to dispose strips 2 and 3 in their relative positions as shown in Figure 1, slide strip 4 in between them so that the flanges on channels 5 and 10 engage in the grooves on the plastics strip, and then run the composite strip through a pressure roller system to crimp the component metal strips together. They can then be cut as desired to form a window frame of any desired size and shape.

The remaining components of the double glazing system shown in Figure 1 are more or less conventional. Thus, two sheets of glass 20, 21, spaced apart by a hermetically sealed spacer tube 22, which is sealed in the system by an enveloping sealing mastic and covering tape, are mounted on the composite frame. A glazing bead 23, suitably of aluminium, is mounted on the outer frame 3 and carries a resilient beading 24 of any suitable material (e.g. a vinyl plastic) and construction. A primary seal of mastic tape 25 is held against the inner glass sheet 20 by a channel 26 formed on the inner frame 2.

In the construction shown in Figure 3, the surrounding main window frame 31 is identical to the frame 3 shown in Figure 1. The frame of the fanlight 30 and the lower frame member 32 are of similar construction, but involve inner and outer frame members of slightly different pofiles. The plastics strips 4 and 40 are, as can be seen, adjacent the inner surfaces of the window frames.

In the embodiment shown in Figure 4, the horizontal limbs 51 and 52 of the plastics strip include longitudinal grooves 51a, 51b, 52a and 52b whose bases are formed at an angle of 30 to the horizontal. Flanges 60 and 61 of outer frame strip 53 engage in grooves 52a and 52b respectively. Corresponding flanges on an inner frame strip (not shown) engage in grooves 51a and 51b and form a secure mechanical seal.

It will be appreciated that although the specific description herein refers to windows and window frames, the invention is equally applicable to the provision of doors and door frames.

WHAT WE CLAIM IS:- 1. 1. A composite strip formed of two lengths of extruded metal wherein each length is provided with a longitudinally extending channel, held together solely by a pre-formed strip of synthetic plastics material retained in each channel by opposed longitudinal flanges extending from the sides of the channels each engaging longitudinal grooves formed in the plastics strip.

2. A strip as claimed in claim 1 wherein the plastics material is one which has thermal insulating properties.

3. A strip as claimed in claim 1 or 2 wherein the metal is aluminium.

4. A strip as claimed in any of claims 1 to 3 wherein the pre-formed strip of plastics material is an extruded strip and has a cross section substantially in the form of a Greek cross in which the extremities of two opposed limbs are extended at right angles to form grooves bounded by the extensions and the other two limbs.

5. A strip as claimed in claim 5 wherein the bases of the grooves are formed at an angle to said two opposed limbs.

6. A strip as claimed in claim 5 wherein said angle is of the order of 30".

7. A strip as claimed in claim 1 substantially as hereinbefore described with reference to the drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

the channel of one of the metal extrusions, whereupon the other extrusion is slidden over the plastics strip. Alternatively, the two metal extrusions may be placed with their channels facing each other and the plastics strip pushed into the two channels simultaneously.

In the drawings accompanying the Pro visional Specification and the accompanying drawings, which illustrate the invention, Figure 1 is an elevation, partly cut away and in section, of a corner of a double-glazing window frame in accordance with the invention; Figure 2 is a cross-section of the plastics strip of Figure 1, on a larger scale; Figure 3 is a schematic view showing a fanlight in a window frame, in both open and closed positions; Figure 4 is a cross-section of another form of plastics strip; and Figure 5 shows the profile of a modified outer frame member, to be used in conjunction with a strip such as that of Figure 4.

The window frame 1 comprises an inner frame 2 and an outer frame 3 joined together by a strip of plastics material 4. The metal strip forming inner frame 2 and that forming outer frame 3 are extruded separately, are joined together by means of the plastics strip 4, and are then cut and mitred and formed into conventional rectangular shape.

The inner frame 2 is provided with a longitudinal channel 5 formed by upper and lower arms 6, 7, which arms have inwardly directed flanges 8, 9 respectively.

Outer frame 3 is formed with a similar channel 10. The plastics strip 4 (see Figure 2) is basically of Greek cross section, but each of its horizontal limbs, 11, 12, is provided with extensions at its extremities which form longitudinal grooves lia, lib, 12a and 12b. It will be seen that flanges 8 and 9 engage in grooves 1 lea and 1 Ib respectively, and the flanges of channel 10 are similarly engaged in grooves 12a and 12b.

In order to ensure that metal extrusions 2 and 3 are firmly held together pressure can be exerted on the composite strip, suitably by opposed rollers, in the directions shown by the arrows in Figure 1. It will be normal practice, in assembling the composite metal strip, to dispose strips 2 and 3 in their relative positions as shown in Figure 1, slide strip 4 in between them so that the flanges on channels 5 and 10 engage in the grooves on the plastics strip, and then run the composite strip through a pressure roller system to crimp the component metal strips together. They can then be cut as desired to form a window frame of any desired size and shape.

The remaining components of the double glazing system shown in Figure 1 are more or less conventional. Thus, two sheets of glass 20, 21, spaced apart by a hermetically sealed spacer tube 22, which is sealed in the system by an enveloping sealing mastic and covering tape, are mounted on the composite frame. A glazing bead 23, suitably of aluminium, is mounted on the outer frame 3 and carries a resilient beading 24 of any suitable material (e.g. a vinyl plastic) and construction. A primary seal of mastic tape 25 is held against the inner glass sheet 20 by a channel 26 formed on the inner frame 2.

In the construction shown in Figure 3, the surrounding main window frame 31 is identical to the frame 3 shown in Figure 1. The frame of the fanlight 30 and the lower frame member 32 are of similar construction, but involve inner and outer frame members of slightly different pofiles. The plastics strips 4 and 40 are, as can be seen, adjacent the inner surfaces of the window frames.

In the embodiment shown in Figure 4, the horizontal limbs 51 and 52 of the plastics strip include longitudinal grooves 51a, 51b, 52a and 52b whose bases are formed at an angle of 30 to the horizontal. Flanges 60 and 61 of outer frame strip 53 engage in grooves 52a and 52b respectively. Corresponding flanges on an inner frame strip (not shown) engage in grooves 51a and 51b and form a secure mechanical seal.

It will be appreciated that although the specific description herein refers to windows and window frames, the invention is equally applicable to the provision of doors and door frames.

WHAT WE CLAIM IS:- 1. 1. A composite strip formed of two lengths of extruded metal wherein each length is provided with a longitudinally extending channel, held together solely by a pre-formed strip of synthetic plastics material retained in each channel by opposed longitudinal flanges extending from the sides of the channels each engaging longitudinal grooves formed in the plastics strip.
2. A strip as claimed in claim 1 wherein the plastics material is one which has thermal insulating properties.
3. A strip as claimed in claim 1 or 2 wherein the metal is aluminium.
4. A strip as claimed in any of claims 1 to 3 wherein the pre-formed strip of plastics material is an extruded strip and has a cross section substantially in the form of a Greek cross in which the extremities of two opposed limbs are extended at right angles to form grooves bounded by the extensions and the other two limbs.
5. A strip as claimed in claim 5 wherein the bases of the grooves are formed at an angle to said two opposed limbs.
6. A strip as claimed in claim 5 wherein said angle is of the order of 30".
7. A strip as claimed in claim 1 substantially as hereinbefore described with reference to the drawings.
8. A window frame for a double glazing

system formed from composite strip as claimed in any of claims 1 to 7.
9. A window frame substantially as hereinbefore described with reference to the drawings.