GB2258282A

GB2258282A - Fixing arrangement e.g. for roofs

Info

Publication number: GB2258282A
Application number: GB9214736A
Authority: GB
Inventors: Brian Christopher Allport; Susan Margaret Allport; Mark Charles Allport; Phillip Brian Allport; Hannah Susan Allport
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-08-01
Filing date: 1992-07-10
Publication date: 1993-02-03
Anticipated expiration: 2012-07-10
Also published as: IE912747A1; GB2258282B; IE65001B1; GB9214736D0

Abstract

A fixing arrangement comprises a capping member 14 provided with an aperture 16 having a countersunk portion 16', the aperture 16 receiving a dished sealing washer 22 and a countersunk screwhead 20. The washer 22 is of plastics and the outer edge of the washer 22 is visible around the screwhead 20. A pre-fabricated roof assembly includes a capping member 14 which bridges across the gap between a pair of glass panels and is secured by screws 15 which pass through the gap to a roof rafter. <IMAGE>

Description

This invention relates to a fixing arrangement, especially but not exclusively to a fixing arrangement used in a pre-fabricated building, for example a roof assembly, and which provides a neat and efficient seal against the weather.

According to the present invention there is provided a fixing arrangement including a first member secured to a second member by at least one screw extending through an aperture in the first member, wherein the aperture is formed with a dished countersunk region for accommodating the head of the screw, the arrangement further including a dished sealing washer which has an exterior surface substantially conforming to the shape of the countersunk region of the aperture and an interior surface substantially conforming to the shape of the flange of the head of the screw and which is maintained under pressure between the flange of the head of the screw and the countersunk region of the aperture.

As used herein, the term "screw" is intended to include bolts and like fixing devices having an enlarged head and a threaded shank.

In its application to pre-fabricated buildings the invention provides a pre-fabricated assembly including a frame member which is overlapped on opposite longitudinal edges by the respective edges of a pair of panel units, the panel units being held in place by an elongate capping member which overlaps the said edges of the panel units on the opposite side thereof to the frame member, and the capping member being secured to the frame member by a series of screws disposed spaced apart along the length of the capping member, the screws extending through respective apertures in the capping member and passing to the frame member via a gap between the adjacent edges of the panel units, wherein the apertures in the capping member are formed with a dished countersunk region on the external surface of the capping member for accommodating the head of the respective screw, the assembly further including a dished sealing washer which has an exterior surface substantially conforming to the shape of the countersunk region of the aperture and an interior surface substantially conforming to the shape of the flange of the head of the screw and which is maintained under pressure between the flange of the head of the screw and the countersunk region of the aperture.

Preferably, to provide an immediate visible confirmation that a sealing washer has been used in association with the screw, the outer edge of the sealing washer is visible around the head of the screw.

The invention also provides a capping member fdr use in a pre-fabricated assembly as specified above.

The advantage of the invention is that it is neat and compact compared to current techniques which use large top fixing washers and caps which result in unsightly projections above the level of the fixing member.

An embodiment 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 a part of a pre-fabricated roof assembly incorporating an embodiment of the invention; Figure 2 is a cross-sectional view similar to that of Figure 1; Figure 3 is a perspective view of the capping member used in the assembly of Figures 1 and 2, together with a sealing washer and screw; and Figure 4 is a cross-sectional view of the fixing member and washer of Figure 3.

Referring to the drawings, a pre-fabricated roof assembly includes a roof frame member in the form of a wooden rafter 10 which is overlapped on its opposite longitudinal edges 11 by the respective edges 12 of a pair of triple glazing panels 13. The panels 13 are held firmly in place by an elongate fixing member 14 (herein called a capping member) which overlaps the edges 12 of the panels 13 on the opposite side thereof to the rafter 10. The capping member 14 itself is secured to the rafter 10 by a series of screws 15 disposed spaced apart centrally along the length of the capping member 14, the screws 15 extending through respective apertures 16 (figures 3 and 4) in the capping member 14 and passing to the rafter 10, into which they are screwed, via the gap between the adjacent edges 12 of the panel 13.Thus the edges 12 of the panels 13 are clamped between the rafter 10 and the capping member 14.

The capping member 14 is made for example from extruded aluminium, and is of shallow generally arched or inverted V-shaped cross section. Each longitudinal edge of the member 14 has a recess 17 for accommodating a respective weather seal 18 which seals against the respective glazing panel 13. Similar seals 18 are provided in recesses formed along the opposite edges 11 of the rafter 10.

It is to be understood that the capping member 14 is highly elongated in a direction out of the plane of Figures 2 and 4, and that in Figure 3 only a short part of the length of the capping member 14 is shown.

It is further to be understood that Figures 1 and 2 show only a small part of the roof assembly. The full assembly will have a plurality of rafters with a plurality of glazing panels each spanning two rafters, and each rafter will support and have fixed thereto by their edges in the manner shown a pair of glazing panels.

Thus far, the assembly corresponds generally to known structures. The main difference lies in the means for fixing the various components together, as will now be described.

According to the embodiment of the invention, the apertures 16 in the capping member 14 are formed by an inverted "bell-shaped" punch. This provides that each aperture 16 has two axially adjacent parts, a shallow curved concave part forming a dished countersunk region 16' on the external surface of the capping member 10, and a short cylindrical part 16" extending from the inner end of the region 16' to the inside surface of the member 14.

Each screw 15 has a tapered (i.e. conical) head flange 20, and the unthreaded shank portion 21 of the screw 15 has substantially the same diameter as the cylindrical portion 16".

Each screw 15 has an associated dished sealing washer 22 made of nylon, the exterior surface 22' of the washer 22 having a curved convex shape substantially conforming to the curved concave shape of the countersunk region 16' of the aperture 16. The interior surface 22" of the sealing washer 22 has a conical shape substantially conforming to the shape of the tapered head flange 20 of the screw 15. In the finished structure, Figures 1 and 2, each sealing washer 22 is maintained under pressure between the head flange 20 of the respective screw 15 and the countersunk region 16' of the aperture. As the head flange 20 of the screw 15 tightens into the countersunk region 16' the sides of the sealing washer 22 are forced into the curved countersunk region 16' and the tapered head flange 20 engages the similarly shaped interior sides 22" of the washer 22 to ensure that the washer 22 provides a neat and efficient seal around the head flange 20 of each screw 15.

An additional advantage of the above arrangement compared to conventional arrangements is that there is no tendency for the washer to split or be forced out of its cavity; rather the reverse is the case since as the screw 15 tightens by being screwed down into the rafter 10 the sealing washer is forced tighter into the countersunk region 16'.

Preferably, to provide an immediate visible confirmation that a washer 22 has been used in association with the screw 15, the outer edge 23 of the washer is visible around the head of the screw 15 even after the latter has been tightened up.

Claims

CLAIMS:

1. A fixing arrangement including a first member secured to a second member by at least one screw extending through an aperture in the first member, wherein the aperture is formed with a dished countersunk region for accommodating the head of the screw, the arrangement further including a dished sealing washer which has an exterior surface substantially conforming to the shape of the countersunk region of the aperture and an interior surface substantially conforming to the shape of the flange of the head of the screw and which is maintained under pressure between the head flange of the screw and the countersunk region of the aperture.

2. A pre-fabricated assembly including a frame member which is overlapped on opposite longitudinal edges by the respective edges of a pair of panel units, the panel units being held in place by an elongate capping member which overlaps the said edges of the panel units on the opposite side thereof to the frame member, and the capping member being secured to the frame member by a series of screws disposed spaced apart long the length of the capping member, the screws extending through respective apertures in the capping member and passing to the frame member via a gap between the adjacent edges of the panel units, wherein the apertures in the capping member are formed with a dished countersunk region on the external surface of the capping member for accommodating the head of the respective screw, the assembly further including a dished sealing washer which has an exterior surface substantially conforming to the shape of the countersunk region of the aperture and an interior surface substantially conforming to the shape of the flange of the head of the screw and which is maintained under pressure between the head flange of the screw and the countersunk region of the aperture.

3. An assembly as claimed in claim 2, wherein the outer edge of the washer is visible around the head of the screw.

4. An assembly as claimed in claim 3, wherein the washer is made of a semirigid plastics material.

5. A capping member for use in a pre-fabricated assembly as claimed in claim 2, comprising a rigid elongate member having a generally arched or inverted V-shaped cross-section and a plurality of apertures disposed along the length of the member, each aperture having a dished countersunk region on the outer surface of the member.

6. A sealing washer for use in a pre-fabricated assembly as claimed in claim 2, the washer having a conical interior surface and a convex curved outer surface.

7. A washer as claimed in claim 6, where in the washer is made of a semirigid plastics material.

8. A roofing assembly substantially as described with reference to the accompanying drawings.

9. A capping member substantially as described with reference to the accompanying drawings.