Access panel frame

Abstract

A frame for an access panel or door comprising a plurality of linear frame members joined together at their ends, each comprising a fixed member (1, 2) and an external adjustable member 4 hinged there

Description

Field of the Invention This invention relates to a frame for an access panel or door, for example for use where fire resistance and / or sound insulation is important. Background to the Invention Installing four-sided framed access panels or doors in fire rated situations requires the fitting gap between the wall and the frame to be ‘closed’ to prevent fire passing through the gap. This process is known as ‘Firestopping’ and is traditionally achieved by stuffing the gap with a fire resistant material like Rockwool insulation materials or filling the gap with a fire resistant mastic, or a combination of the two. Unlike timber door sets and frames where architraves bridge and close off the gaps, a preformed access panel frame is intended to be fitted into an aperture in a wall or ceiling with no additional framing to the face. Most access panels are designed to fit flat to the surface of the wall or ceiling so the firestopping has to be done from the back and is difficult to pack gaps that may be as little as 5mm wide. Additionally, installation requires packers at the position where the fixing screws secure the frame to the wall or ceiling. Without packers, overtightening the fixing screws can easily deform metal or plastic frames by pulling the frame into the gaps at the aperture sides where the aperture is not the exact size for the frame. This distortion of the frame being pulled to the aperture sides leads to the frame being forced out of square. Traditionally timber, plastic or metal packers are used to fit in the gap between the door and frame which support the frame at the fixing point preventing the frame from being distorted. Fitting the packers is awkward, time consuming and expensive if metal packers have to be used because of fire reasons. Where an acoustic rating is to be achieved, this requires the gap between the frame and aperture to be sealed, which is traditionally achieved using a skeleton gun to caulk the gap between frame and wall or ceiling. This is a messy process and liable to drops in performance if areas cannot be reached. Some existing solutions using slide out or expanding frame options require the slide out part to be the primary fixing to the aperture sides. The frame of the access panel or door is then fixed to the slide out or expanded frame section. This is adding a step in the fixing time and relying on the interconnecting screws or bolts to perform as well as fixings that would be into the wall or ceiling section. A further problem when using loose supplied slide-on or expanding frame sections is that there is always a gap to the corners. Some solutions have triangular parts that also separately slide out and are in turn screwed in place. This method limits the corner cover size and adds a further step to fix the slide out corners in place. Additionally when using loose supplied slide-on or expanding frame sections, separately supplied wind-out bolts are required to locate the slide out parts against the aperture before fixing the slide out sections. Wind-out bolts need to be removed before the door can be closed and this adds another process to the fixing procedure. When using traditional style pedestrian metal door frame fixings, these fixing are threaded into the frame to extend out from the frame to locate against the aperture sides. The fixings are hollow so fixing screws can then fix through the fixing. Access panels and doors have thinner frames than pedestrian style doors so the frame is liable to distort at the hollow fixing point load point. Also, when using hollow fix wind-out fixed through bolts the wind-out mechanism is limited in its length, as access panels and doors have shallower frames than pedestrian doors. The mechanism can drop out of the frame if it is overextended. Squaring an access panel or door into an aperture that may not be perfectly square requires the packers to support the panel or door differently in different fixing positions to hold the panel or door square. This is achieved on site with different size packers used in different positions which extends the fitting time in uneven apertures. Frames with profiles that present a void to the aperture edge are difficult to fix. Not seen in solid timber sections, the steel frame is a folded profile that, depending on the wall or ceiling thickness, may present a hollow part at the ap erture edge. This has the fixing effect of unevenly supporting the frame so it can twist during fitting. The present invention provides a frame for an access panel or door that seeks to overcome these problems. Summary of the Invention According to the invention, there is provided a frame for an access panel or door comprising a plurality of linear frame members joined together at their ends, each frame member comprising a fixed member and an adjustable member hinged thereto along its length and external to the frame, and means operative between the fixed member and the adjustable member to hinge the adjustable member away from the fixed member. Other features of the frame are set out in the claims. The invention also provides a method of fixing a frame for an access panel or door in an opening in a wall or ceiling of a building, comprising locating a frame according to the invention into the opening, hinging each adjustable member outwardly from the frame so as to bear against the respective sides of the opening, and then securing the frame to the said sides. The frame of the invention is straightforward to install and provides a secure fire-resistant and / or sound-reducing seal. Brief Description of the Drawings In the drawings, which illustrate an exemplary embodiment of the invention: Figure 1 is a sectional view of a portion of a wall with an opening therein, into which a frame in accordance with the invention has been located; Figure 2 is a view corresponding to that of Figure 1, showing the first stage of fixing of the frame in the opening; Figure 3 is a view corresponding to that of Figures 1 and 2, showing the second stage of fixing; Figure 4 is a perspective view from one side of a portion of an opening and frame inserted therein; and Figure 5 is a perspective view from the other side, showing a portion of the completed frame with a corner member in position. Detailed Description of the Illustrated Embodiment Referring to Figure 1, the frame is formed from linear frame members fabricated from sheet steel with an inner (relative to the frame) component 1 having a generally rectangular channel section 1a with a planar section 1b extending to one side thereof and having on its side remote from the channel section a flange 1c extending normally to the planar section and on the opposite side thereof from the channel section. Within the channel section 1a a second channel-shaped component 2 is welded, serving to stiffen the channel section 1a and providing a support for an adjusting screw 3, described hereinafter. An adjustable component 4 consists of a resiliently-deflectable metal strip extending the length of the frame member, welded to planar section 1b of the inner component 1 adjacent to the flange 1c and having an upstand 4a along its edge opposite to the weld extending into the channel section 1a. The adjustable component 4 is provided with intumescent strips 5 extending along it on the outwardly-facing surface thereof adjacent to the upstand. Adjusting screws 3 are threaded through the second channel-shaped component at intervals along it to engage the inner side of the adjustable component 4. Corresponding access holes 6 formed in the channel section 1a to permit access for a screwdriver or Allen key or the like for driving the screws. In use, an opening is formed in a building structure 7, for example formed of block work 8 and a double layer 9 of plasterboard on each face. It will be appreciated that the building structure could be of any form, for example brickwork, timber partition, and steel stud, typically faced with plasterboard, although other optional finishing surfaces may be used. The frame is located in the opening with the flanges 1c of the frame members resting against the external face of the plasterboard layer 9. The screws 3 are then rotated to deflect the adjustable components 4 outwardly of the frame and into contact with the block work 8, with the intumescent strips 5 held firmly against the block work, as illustrated in Figure 2. The frame is then secured in place by means of frame screws 10 driven into the block work 8 through apertures provided at intervals along the frame members, as shown in Figure 3. Figure 4 shows a portion of the frame located in the opening, the view being from the side where the flanges 1 c are in contact with the plasterboard 9 surrounding the opening. It will be observed that there might be a potential vulnerability at the corners, but with reference to Figure 5 the solution is through the use of corner seals 11 each consisting of a triangular steel member with flanges extending normally thereto along each of the shorter sides thereof. These flanges are inserted, in use, between adjacent adjustable members and the sides of the opening before the adjustable members are moved into full contact with the sides of the opening. Screwing down the adjustable members into contact with the side of the opening serves to trap the corner seals in position, sealing the corners. Intumescent seals may be provided on the flanges of the corner seals to ensure continuity of sealing though the corners. It will also be seen from Figures 4 and 5 that the frame members are joined together at the corners of the frame by means of angle pieces 12 which serve to ensure that the frames are right angles at the corners. It will be appreciated, however, that the invention could be applied to other shapes with linear sides, rather than just rectangles. Advantages of the frame of the invention include: • The frame fills the gap, negating the need for mineral wool packing. The built in layers of intumescent to the outside expand during a fire ensuing the seal. • The fixing positions are adjacent to the captive screw or bolt that pushes the adjustable members out so the frame is supported at the exact position the wall fixing screw is trying to deform the frame. • The frame can be fitted with a flexible acoustic seal that will seal itself against the aperture sides. • The adjustable members are captive / fixed to the frame and pivot away to seal the gap. • The frame does not require extra fixings into the wall or to other expanded frame sections. • The corner seals cover the corner gaps and can be provided in larger sizes for larger gaps. • No additional bolts are required to wind out the adjustable members; the captive screws are used. 5 • The adjustable members are substantially the full length of the frame side so there are no point loads to distort the frame. • The adjusting screws are captive and will not fall out once they are at the end of their travel. Longer bolts can be specified to cover larger gaps. 10 • The adjustable members can be wound out to level and position the access panel or door in its aperture. • The flanges around the frame present a flat face to the aperture edges allowing a twist free fixing to take place.

Claims

1. A frame for an access panel or door comprising a plurality of linear frame members joined together at their ends, each frame member comprising a fixed member and an adjustable member hinged thereto along its length and external to the frame, and means operative between the fixed member and the adjustable member to hinge the adjustable member relative to the fixed member.

2. A frame according to Claim 1, wherein each fixed member has at least one screw threaded therethrough and configured to engage the adjustable member whereby rotation of the screw causes hinging movement of the adjustable member relative to the fixed member.

3. A frame according to Claim 1 or 2, wherein each fixed member has a plurality of said screws spaced along the length thereof and threaded therethrough.

4. A frame according to Claim 1,2 or 3, wherein the surface of each adjustable member facing outwardly from the frame is provided with a continuous strip of a sealing material along the length thereof.

5. A frame according to Claim 4, wherein the sealing material is an intumescent material.

6. A frame according to Claim 4, wherein the sealing material is an acoustic sealing material.

7. A frame according to any preceding claim, wherein the adjustablemember is formed from a resiliently bendable material bonded along one edge to the fixed member.

8. A frame according to Claim 7, wherein the adjustable member is formed from metal welded along one edge to the fixed member.

9. A frame according to Claim 8, wherein each frame member includes a fixing hole therethrough for receiving a fixing screw for attachment of the frame in an opening.

10. A method of fixing a frame for an access panel or door in an opening in a wall or ceiling of a building, comprising locating a frame according to any preceding claim into the opening, hinging each adjustable member outwardly from the frame so as to bear against the respective sides of the opening, and then securing the frame to the said sides.

11. A method according to Claim 10, comprising before the hinging step locating at each corner of the frame a triangular corner piece having flang-5 es extending normally to two sides of the triangle such that the flanges are located between the sides of the opening and the adjustable members of the frame, and then hinging the adjustable members of the frame against the sides of the opening so as to clamp a part of the flanges of the corner pieces, thereby sealing the corners of the frame.10 12. A method according to Claim 10 or 11, comprising securing theframe in the opening with fixing screws passed through the frame and into the structure surrounding the opening.

Images