GB2119001A - Trap door for a loft - Google Patents

Abstract

The trap door comprises a frame formed from sheet metal and comprising upstanding side walls (1), a continuous outwardly directed flange (2) for abutting the ceiling around a loft opening and an internal flange (5) against which the lid or cover (6) abuts when closed. A catch (9, 10) is provided for securing the lid or cover in closed position. Preferably the lid or cover (6) is releasably hingedly secured to the frame. <IMAGE>

Description

SPECIFICATION Trap door for a loft opening This invention relates to trap doors for lofts in buildings such as dwelling houses.

Buildings having lofts are generally provided with a trap door whereby access can be gained to the loft. Usually such trap doors comprise a wooden frame which is built in situ and a loose hatch or cover of wood, block-board or the like which rests on a ledge provided by the frame and which has to be physically lifted up into the loft space and manoeuvred sideways to clear the loft opening in order to open the trap door and which has to be manoeuvred back over the loft opening and physically lowered back onto its supporting ledge in order to close the trap door. The building of such known trap doors in situ is a time consuming task which is usually carried out by a highly paid skilled person such as a carpenter.

Such known trap doors also suffer from the disadvantages that the hatch or cover when in its its closed position is recessed into the frame, which detracts from the appearance of the trap door, and that when the loose hatch or cover is being manhandled to open or close the trap door it frequently becomes marked with dirty finger or hand prints due to dust which has gathered in the loft space and thus has to be washed or cleaned whenever the trap door is used. In addition, if a loft ladder is fitted to facilitate access to the loft space then the trap door has to be modified so that the hatch or cover is hinged to the frame and will open downwardly.

The present invention has as its object to provide a trap door for a loft opening which overcomes the aforsaid disadvantages with known trap doors.

The present invention provides a preformed trap door for a loft opening comprising a frame having, in its position of use, unstanding side walls provided with means whereby the frame can be secured to ceiling joists between which the loft opening is formed, an outwardly directed flange at the lower edges of said side walls for abutting a ceiling around a loft opening, a lid or cover hingedly connected to said frame and adapted to open downwardly when the trap door is in use, and catch means for releasably securing the lid or cover in its closed position.

The frame is preferably formed from sheet metal, e.g., sheet steel or sheet aluminium.

Generally the ceiling joists in buildings are spaced a standard distance apart so that ceiling boards of standard size can be secured thereto and accordingly the frame can be made in one or more standard sizes to suit the standard spacing between ceiling joists. The frame may be a square or rectangular frame having opposed upstanding side walls and said outwardly directed flange may be a continuous flange to provide a neat finish around the loft opening. The frame may also include an internal flange which extends inwardly from said upstanding side walls at a predetermined distance above the lower edges of said side walls against which the lid or cover abuts when in its closed position.Preferably said internal flange is at such a distance above the lower edges of said upstanding side walls and the lid or cover is so hinged to the frame that the lower surface of the lid or cover will be recessed within the frame by a minimum amount or will be in substantially the same plane as the lower surface of the said outwardly directed flange with the lid or cover is in its closed position. This again adds to the generally appearance of the trap door.

Said means whereby the frame can be secured to ceiling joists between which the loft opening is formed may comprise apertures or slots in said upstanding side walls for the reception of screws or other suitable fastening means for securing the frame to said joists.

The lid or cover may be formed from any suitable material, e.g., may be formed from metal, wood, plywood, blockboard or the like. Preferably, however, the lid or cover is formed from sheet metal, e.g., sheet aluminium, and comprises a pair of opposed tray members which are adapted to fit one within the other and which are secured, e.g., rivetted together. Suitable heat and/or sound insulating material such as a suitable foamed plastics material, mineral wool, or the like is preferably sandwhiched between said tray members before they are secured together.

Alternatively the lid or cover may comprise a single tray member comprising a planar bottom wall and an upstanding rim around said bottom wall to provide a recess for the reception of a block or blocks of insulating material, e.g., a block of expanded polystyrene or a block of mineral wool.

The said catch means for releasably securing the lid or cover in its closed position may be of any suitable kind and may, for example, comprise a suitable spring catch or catches of the kind which catches when the two components thereof are first pressed together and which releases when the components thereof are next pressed together or may comprise a suitable magnetic or other catch or catches. Preferably the lid or cover is releasably hingedly connected to the frame so that it can be removed from the frame if desired. To this end the lid or cover may be hingedly connected to the frame by hinged pins which extend outwardly from the lid or cover on opposite sides thereof and engage opposed apertures in the frame, at least one of said hinge pins being retractable against a spring bias to release the lid or cover from the frame.The ability to readily release the lid or cover from the frame has been found to be useful in that it greatly facilitates the mounting of the frame in the loft opening and in that it facilitates manoeuvreing relatively large objects through the loft opening when the trap door has been fitted.

The frame, or at least said outwardly directedflange thereof, and the lid or cover, or at least the lower surface thereof, may be provided with a suitable surface finish, e.g., may be painted, stove enamelled, anodised or the like.

The invention will be more particularly described with reference to the accompanying drawings in which:~ Figure 1 is an underneath plan view of a frame of a trap door according to the present invention, Figure 2 is an end elevation of the frame shown in Figure 1.

Figure 3 is a section on the line A-A of Figure 1, Figure 4 is an underneath plan view of a lid or cover for the trap door, Figure 5 is a side elevation of the lid or cover, Figure 6 is an end elevation of the complete trap door, and Figure 7 is a fragmentary sectional view of another embodiment of a trap door according to the present invention.

Referring to Figures 1 to 3 it will be seen that the preformed frame is of square or rectangular shape and comprises opposed upstanding side walls 1 having a continuous outwardly directed flange 2 extending around the lower edges thereof. The upstanding side walls 1 and flange 2 are formed from suitable angle material which is cut and welded to form the frame. Slots 3 and apertures 4 are provided in each of the upstanding side walls 1 whereby the frame can be secured, e.g., screwed, to ceiling joists between which a loft opening is formed. An internal flange 5 extending inwardly from the side walls 1 is provided at a predetermined distance above the lower edges of the side walls 1 against which a lid or cover 6 (Figures 4 to 6) abuts when in its closed position. The internal flange is formed from angle material secured, e.g., welded, to the side walls 1.

At one end of the frame as shown in Figure 1 a pair of nuts 7 are secured, e.g., welded in apertures in the side walls 1, the nuts 7 serving for the reception of threaded pivot pins 8 (Figure 6) for the lid or cover 6. At the opposite end of the frame one component 9 of a spring catch is secured centrally of the side wall 1 by means of suitable bolts or rivets 10. The other latch component 11 of the spring catch is secured to the lid cover 6 as by means of rivets or the like as shown in Figure 5.

The lid or cover 6 shown in Figures 4 and 5 is formed from sheet metal, e.g., sheet aluminium, and comprises two opposed tray members 12 and 13 which fit one within the other and which are secured together by means of rivets indicated diagrammatically at 14 inserted through the cooperating flanges thereof. The hollow interior of the lid or cover 6 between the opposed tray members 12 and 13 is filled with a suitable thermal and/or sound insulating material (not shown) such as a suitable foamed plastics material, mineral wool or the like. Apertures shown diagrammatically at 15 in Figure 5 are provided in opposed side walls of the lid 6 at the opposite end thereof to the latch component 11 for the reception of the pivot pins 8 whereby to pivotally connect the lid or cover 6 to the frame.

As will be seen from Figure 6 the internal flange 5 of the frame is positioned at such a distance above the lower edges of the side walls 1 and the lid or cover 6 is so hingedly connected to the frame that when the lid or cover 6 is in its closed position as shown in Figure 6 the lower surface thereof is recessed within the frame by a minimum amount e.g., of the order of 6.35 mm; or is in substantially the same plane as the lower surface of the outwardly directed flange 2.

Referring now to Figure 7 of the drawings it will be seen that the embodiment illustrated therein, in which like parts have been given like reference numerals, the preformed frame is formed in two parts 16, 17 from sheet metal, the first part 16 comprising the outwardly directed flange 2, part 1 a of the upstanding side walls 1 and an inturned flange 5a forming part of the internal flange 5 whilst the other part 1 7 comprises an inturned flange 5b which is spot welded or otherwise secured to the inturned flange 5a to form the flange 5 and upstanding side wall parts 1 b which cooperate with the side wall parts 1 a to form the side walls 1.The lid or cover 6 in this embodiment is in the form of a single tray having a planar bottom wall 18 and an upstanding peripheral rim 19 which terminates in an inturned flange 20, thus providing a recess in the top of the lid or cover 6 for the reception of a block of insulating material (not shown). The lid or cover 6 is releasably hingedly secured to the frame by meansof a pair of hinge pins which extend outwards on opposite sides thereof and engage opposed apertures in the frame. At least one of the hinge pins is retractable against a spring bias as shown in Figure 7 to enable the lid or cover 6 to be released from the frame and comprises a hinge pin 21 mounted for longitudinal sliding movement in apertures in a bracket 22 mounted, e.g., spot welded on the bottom wall 18.A helical spring 23 is mounted on the hinge pin 21 between a washer or other abutment 24 fixedly secured to the hinge pin 21 and one end of the bracket 22 so as to urge the hinge pin 21 into engagement with an aperture 25 in a side wall 1 of the frame. If desired blocks or sheets of sound and/or heat insulating material may be provided around the inside of the side wall parts 1 b so as to rest on the internal flang 5.

In use the complete preformed trap door is simply offered up to a loft opening so that the outwardly directed flange 2 abuts the #ceiling around the loft opening and the frame is then secured to the joists between which the loft opening has been formed by inserting screws through the slots 3 and/or apertures 4. These operations require no skill and can be carried out by unskilled labour. The flange 2 provides a neat finish around the loft opening and the fact that the lower surface of the lid or cover 6 is substantially flush with the lower surface of the flange 2 provides a pleasing appearance to the trap door when in position in a loft opening. At least the flange 2 of the frame and at least the lower surface of the lid or cover 6 may be provided with a suitable surface finish to enhance the appearance thereof, e.g., may be stove enamelled white or another suitable colour so as to blend in well with the surrounding ceiling.

In the illustrated embodiment the component 9 of the spring catch extends upwardly beyond the upper limit of the side walls 1 of the frame.

According to a modification the side walls 1 of the frame are extended upwardly to substantially the level of the top of the catch component 9.

Although the modification entails the use of more material in the manufacture of the frame it adds to the visual appeal of the finished trap door.

Claims (10)

1. A preformed trap door for a loft opening, a trap door comprising a frame having, in its position of use, unstanding side walls provided with means whereby the frame can be secured to ceiling joists between which the loft opening is formed, an outwardly directed flange at the Iqwer edges of said side walls for abutting a ceiling around a loft opening, a lid or cover hingedly connected to said frame and adapted to open downwardly when the trap door is in use, and catch means for releasably securing the lid or cover in its closed position.

2. A trap door according to claim 1, wherein said frame is formed from sheet metal.

3. A trap door according to claim 1 or 2, wherein said frme is a square or rectangular frame having opposed side walls and said flange is a continuous flange extending outwardly around the four sides of the frame.

4. A trap door according to claim 1, 2 or 3, comprising an internal flange which extends inwardly from said upstanding side walls at a predetermined distance above the lower edges of the side walls to provide an abutment for the lid or cover when in its closed position.

5. A trap door according to any one of the preceding claims, wherein said means whereby the frame can be secured to ceiling joists between which the loft opening is formed comprising apertures or slots in said upstanding side walls for the reception of screws or like fastening means.

6. A trap door according to any one of the preceding claims, wherein said lid or cover is formed from sheet metal material.

7. A trap door according to claim 6, wherein said lid or cover comprises at least one tray member comprising a planar bottom wall and an upstanding rim around said bottom wall to provide a recess for the reception of heat and/or sound insulating material.

8. A trap door according to any one of the preceding claims, wherein said lid or cover is releasably hingedly connected to said frame.

9. A trap door according to claim 8, wherein said lid or cover is hingedly connected to said frame by means of a pair of hinge pins which extend outwards on opposite sides of the lid or cover and which engage opposed apertures in said frame, at least one of said hinge pins being retractable against a spring bias to enable the lid or cover to be released from the frame.

10. A preformed trap door for a loft opening, substantially as herein described with reference to Figures 1 to 6 or Figure 7 of the accompanyin#g drawings.