GB2142950A - Manufacture of roof tiles - Google Patents

Abstract

Roof tiles 2 are formed by shaping tile forming material on pallets each having a ridge 11 adapted to form an elongate channel adjacent one edge of the tile. Retaining members 4 are located on the ridge 11 prior to the introduction of tile forming material onto the pallet, such members 4 becoming embedded in the channel formed in the tile by the ridge 11 and being arranged retainingly to engage a portion of a separate tile which is subsequently assembled to the tile by location thereof in the channel. A verge overlap portion 3 has grooves which are engaged by the retaining member 4 embedded in the roof portion of the tile. <IMAGE>

Description

SPECIFICATION Process and apparatus for the manufacture of roof tiles This invention relates to a process and apparatus for the manufacture by extrusion of roof tiles, and relates in particular to the manufacture of tiles suitable for use at the edge or verge of a roof.

At the edge or verge of a tiled roof it is generally necessary to provide for the sake of appearance and/or adequate weathering an edging member which extends downwardly from the tiles so as to overhang and protect the underlying roof rafters. To this end, traditional verge tiles may be provided which are integrally formed along one lateral edge thereof with a downwardly extending portion arranged in use to overhang the edge of the roof and to protect the outermost roof rafter. Afurther proposal has been to provide separate edging members which for example may be secured to the rafters and arranged to interlock with the free edges of the tiles. However, the provision of separate edging members can complicate the roofing procedure and may represent an increase in overall costs, and therefore in certain instances traditional verge tiles are preferred.

Experience shows that known verge tiles, whilst being convenient to install, present certain difficulties. The shape of the tiles is such that they cannot be produced in the same production runs as ordinary roof tiles, and this means that the texture and colour of the verge tiles may vary as compared with the ordinary tiles which may render the appearance of the finished roof unacceptable. Moreover, the production rate of verge tiles is generally lower than that of ordinary tiles, even when the former are manufactured by an extrusion technique, this technique itself resulting in a further disadvantage in that the maximum height of the overhang portion is limited.Finally, with verge tiles fabricated in the traditional manner, the thickness of the overlap portion is generally similar to that of the remaining part of the tile which results in the tile as a whole being unnecessarily heavy.

Viewed from a first aspect the invention provides a process for manufacturing roof tiles by extrusion which includes shaping the tile forming material by means of a pallet having a ridge adapted to form an elongate channel adjacent one edge of the tile, wherein at least one retaining member is located on the ridge prior to the introduction of material onto the pallet and is maintained in position thereon during shaping of the material, whereby such member becomes embedded in the channel and is arranged retainingly to engage a separate tile portion which is subsequently assembled to the tile by location thereof in said channel.

Thus in accordance with the invention a verge tile may be partially manufactured by extrusion on the same or similar production line as that utilised for the fabrication of ordinary roof tiles, the overhang portion being fabricated separately from the main part of the tile. In this way, the disadvantage of lack of consistency of texture and colour associated with traditional verge tiles may be overcome. Moreover, since the overlap portions of the tiles are fabricated separately, there are no longer restraints on the various dimensions thereof. Verge tiles formed by the process in accordance with the invention may be secured to a roof in exactly the same way as traditional, integrally formed verge tiles.As in the case of traditional verge tiles, the overlap portion of tiles formed by a process in accordance with the invention may extend substantially perpendicular from the main part of the tile, or alternatively may be inclined outwardly.

Preferably, the retaining member embedded in the channel includes one or more clip-like members having spaced arms adapted to grip and retain the upper part of a separate tile portion within the channel. The arms are preferably provided with formations adapted to interengage with corresponding formations on the separate tile portion whereby to provide particularly secure fixing thereof. Such formations may be in the form of inwardly extending portions of the arms of the clip-like members adapted for engagement in lateral grooves formed in the upper part of the separate tile portion.

The clip-like members preferably include a number of lateral projections which are embedded in the channel during fabrication of the tile whereby to retain the member in the channel.

Viewed from a second aspect the invention provides apparatus for manufacturing roof tiles by extrusion, such apparatus comprising pallets adapted to receive and shape tile forming material, each pallet including a ridge adapted to form an elongate channel adjacent the edge of the tiles, each ridge having means for locating thereon a clip-like retaining member adapted to be embedded in the tile channel.

The means for locating the clip-like member may include one or more projections on the upper part of the ridge adapted for engagement with corresponding apertures in the member. The sides of the ridge preferably include recessed portions which receive the arms of the clip-like member whereby such arms project into the channel in the finished tile.

Preferably, the sides of the ridge are obliquely formed such that the sides of the channel defined thereby are inwardly tapered.

With the verge tiles formed by the process and apparatus in accordance with this invention, the channel for receiving the separate overhang portion may run parallel to the lateral edge of the tile.

However, the overhang portions of such tiles in use are generally required to overlap one another and therefore the edge of the main part of the tile remote from the overhang portion must be cut on the bias in order correctly to engage the adjacent roof tiles in the row. This can present manufacturing difficulties and therefore in one preferred form of the present invention, the channel is formed at an angle to the side edge of the tile, whereby cutting of the free edge on the bias to accommodate overlapping of the overhang portions of adjacent tiles may be avoided.

It will be appreciated that the required angling of the channel relative to the edge of the tile will be partly dependent upon the thickness of the overhang portion.

The separate overhang portions of tiles fabricated in accordance with the invention may be of similar length to the main parts of the tiles and may be engaged in the channels thereof so as to be generally co-extensive therewith. However, with this arrangement the overhang portions of adjacent overlapping tiles do not abut one another owing to the edge of the main part of the tile adjacent the channel projecting laterally beyond the overhang portion. Preferably, therefore, the overhang portion is assembled to the main part of the tile such that the rear edge thereof extends beyond the trailing edge of the main tile part, the front end of the overhang portion being recessed in relation to the front edge of the main tile part.In this way, adjacent verge tiles may effectively interlock with one another, the rear end of the overhang portion of one tile extending beneath the overlying tile and directly abutting the recessed part of the overhang portion of such tile.

The invention extends to a roof tile adapted for use at the verge of a roof comprising a first part having an elongate channel adjacent one edge thereof, such channel being laterally inclined relative to the side edge of the tile, and a second, overhang part engaged in the channel and retained therein by means of a retaining member embedded in the first part, the second part extending beyond the first part at the rear end thereof, and being recessed relative to the first part of the front end thereof, whereby such tile may be telescopically engaged with a like tile in use on a roof.

In a preferred embodiment, the rear edge of the overhang portion extends at least 50 mm beyond the rear end of the first part, the front end being recessed by at least 125 mm in relation to the leading edge of the first part.

Certain embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a perspective view of part of a roof incorporating verge tiles in accordance with the invention and of one such tile on an enlarged scale; Figure 2 is a plan view of a retaining member used in the verge tile shown in Figure 1; Figure 3 is a section along line A-A in Figure 2; Figure 4 is a section along line B-B in Figure 2; Figure 5 is a perspective view of part of a pallet used to manufacture the tile shown in Figure 1 illustrating the manner in which the retaining members are located thereon; Figure 6 is a perspective view on an enlarged scale of part of the main part of the tiles of Figure 1 illustrating the retaining member embedded therein;; Figure 7 is a sectional view through part of the tile of Figure 1; Figure 8 is a view similar to Figure 7 illustrating an alternative embodiment of tile; Figure9 is a view similar to Figure 1 illustrating a further embodiment; Figure 10 is a side elevation of the verge tile shown in Figure 9.

Figure 71 is a side elevation of part of the roof shown in Figure 9 illustrating the manner in which the verge tiles interlock; Figure 12 is a plan view of the part of the roof illustrating in Figure 11.

Referring to the drawings, Figure 1 illustrates a verge tile formed in accordance with the invention which includes a first or main part 2 inter-engaged with second overhang or edging part 3 which extends generally perpendicularly to the main part 2.

The parts 2,3 are inter-engaged subsequent to extrusion, clip-like retaining members 4 being embedded in the first part and adapted retaininglyto engage the second part 3 as will be described in more detail below.

The retaining member is shown in detail in Figures 2 to 4, and may be formed from sheet steel, or alternatively from any other corrosion-resistent metal, or even a plastic material. Each member includes a body portion 5 including spaced apertures 6 therein. Extending downwardly from the body portion are spaced arms 8 provided with inwardly directed tile-engaging formations 9, 10. Extending outwardly from the body portion 5 are wings 7 adapted to be embedded in the main tile part as will be described below.

Figure 5 illustrates a manufacturing pallet upon which the main parts of the tiles are fabricated in accordance with this invention. The palate includes adjacent one edge thereof an elongate ridge 11 formed with oblique side edges 14. Prior to the introduction of tile forming material onto the palate, retaining members 4 are located on the upper surface 12 of the ridge 11, projections 13 on the upper surface 12 engaging in the retaining member apertures 6. The arms 8 of the retaining members 4 engage in recesses 30 formed in the side walls 14 of the ridge 11. In Figure 5, two retaining members are illustrated, the first corresponding to that shown in Figures 2 to 4 and the second including only one pair of arms 8 and being provided with an oblong shape aperture 6 adapted to receive an oblong shape projection 13.

In accordance with the illustrated form of the invention tile forming material is introduced onto the palate shown in Figure 5 such that the ridge 11 forms an elongate channel in each tile and the retaining members become embedded in the channel, the wings 7 thereof extending into the tile material as shown in Figure 6. As also shown in Figure 6, by virtue of the oblique side walls 14 of the palate together with the recesses 30 thereof, the channel 18 is outwardly tapered and the free ends of the arms 8 of the retaining members 4 are inwardly spaced from the channel side walls.

As shown in Figure 7, following fabrication of the main tile part 2, an overhang portion 3 may be engaged therewith, the formations 9, 10 on the arms of the retaining members engaging in corresponding channels formed in the overhang portion 3.

Thus, the portion 3 is securely mounted to the main part 2. In order to increase the strength of the engagement there between, a filler 17 of e.g. mastic may be provided which has the additional advantage of sealing the clips against moisture. Figure 8 illustrates an alternative embodiment wherein the overhang portion is angled away from the main tile part.

With the tiles illustrated in Figure 1 it will be seen that the edge portions of the verge tiles adapted for engagement with neighbouring tiles in each row must be cut at a slight angle to the longitudinal direction of the overhang portions 3 whereby such portions may overlap one another adjacent their front and rear ends. Thus, the angling of the tile edges is dependent on the thickness of the overhang portions. Moreover, as also shown in Figure 1, the overlapping parts of the overhang portions 3 cannot directly abut one another since each must overhang the outermost edge of the respective underlying tile 2 which is spaced outwardly from the overhang portion 3 secured thereto.

An alternative embodiment of verge tile is illustrated in Figure 9 which enables these potential disadvantages to be overcome. The verge tile of Figure 9 is fabricated in a similar manner to the tiles shown in Figure 1 (although it will be seen that only a single retaining member4 is used in this case), other than in that the channel of the main part 2 is appropriately inwardly inclined relative to the lateral side edges thereof such that overlapping of adjacent overhang portions 3 in use may be accommodated without the need for angling the tile edges. Moreover, as shown in Figure 10 the rear edge 25 of the overhang portion 3 projects beyond the rear edge 26 of the main part 2, whilst the leading edge 27 of the portion 3 is recessed relative to the leading edge 28 of the part 2. A nib 31 is provided whereby the verge tiles may be secured to the roof battens 32.

The improved inter-engagement of verge tiles in accordance with this embodiment is illustrated in Figures 11 and 12. As shown in those Figures, the tiles engage telescopically and may accommodate different spacings between adjacent roof battens 32, the overlap X of adjacent tiles being variable.

Moreover, it will be seen that the recessing of the overhang portion at the leading edge of the tile has a further advantage in that a gutter may be accommodated.

It will also be seen from Figure 10 that each overhang portion 3 is tapered such that as shown in Figure 11 a stepped appearance of the overlapping portions in use on a roof is avoided.

Claims (14)

1. A process for manufacturing roof tiles by extrusion which includes shaping the tile forming material by means of a pallet having a ridge adapted to form an elongate channel adjacent one edge of the tile, wherein at least one retaining member is located on the ridge prior to the introduction of material onto the pallet and is maintained in position thereon during shaping of the material, whereby such member becomes embedded in the channel and is arranged retainingly to engage a separate tile portion which is subsequently assembled to the tile by location thereof in said channel.

2. A process as claimed in claim 1 wherein the or each retaining member embedded in the channel includes one or more clip-like members having spaced arms adapted to grip and retain the upper part of a separate tile portion within the channel.

3. A process as claimed in claim 2 wherein the arms are provided with formations adapted to interengage with corresponding formations on the separate tile portion whereby to provide secure fixing thereof.

4. A process as claimed in claim 3 wherein the formations are in the form of inwardly extending portions of the arms of the clip-like members adapted for engagement in lateral grooves formed in the upper part of the separate tile portion.

5. A process as claimed in any of claims 2 to 4 wherein the clip-like members include a number of lateral projections which are embedded in the channel during fabrication of the tile whereby to retain the member in the channel.

6. A process as claimed in any preceding claim wherein the channel is laterally inclined relative to the edge of the tile.

7. Apparatus for manufacturing roof tiles by extrusion, such apparatus comprising pal lets adapted to receive and shape tile forming material, each pallet including a ridge adapted to form an elongate channel adjacent the edge of the tiles, each ridge having means for locating thereon a clip-like retaining member arranged to be embedded in the tile channel.

8. Apparatus as claimed in claim 7 wherein the means for locating the clip-like member includes one or more projections on the upper part of the ridge adapted for engagement with corresponding apertures in the member.

9. Apparatus as claimed in claim 7 or 8 wherein the sides of the ridge include recessed portions which receive the arms of the clip-like member whereby such arms project into the channel in the finished tile.

10. Apparatus as claimed in claim 9 wherein the sides of the ridge are obliquely formed such that the sides of the channel defined thereby are inwardly tapered.

11. A roof tile adapted for use at the verge of a roof comprising a first part having an elongate channel adjacent one edge thereof, such channel being laterally inclined relative to the side edge of the tile, and a second, overhang part engaged in the channel and retained therein by means of a retaining member embedded in the first part, the second part extending beyond the first part at the rear end thereof, and being recessed relative to the first part at the front end thereof, whereby such tile may be telescopically engaged with a like tile in use on a roof.

12. A process for manufacturing roof tiles substantially as herein described with reference to any of the accompanying drawings.

13. Apparatus for manufacturing roof tiles substantially as herein described with reference to any of the accompanying drawings.

14. Roof tiles substantially as herein described with reference to Figures 9 to 12 of the accompanying drawings.