NZ194823A - Demountable adjustable staircase: paired stringer segments - Google Patents

Description

194823 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION AFTER PROVISIONAL NO: 194823 DATED; 2ND SEPTEMBER, 1980 STAIRS AND STAIR BRACKETS I_, PETER WILMOT SETON, a New Zealand citizen of: 306C Jervois Road, Heme Bay, Auckland, New Zealand, do hereby declare the invention for which we pray that a patent may be granted to me and the method by which it is to be performed, to be particularly described in and by the following statement. 194823 This invention relates to a framework suitable for use in building a demountable staircase, or terrace seating or the like.

The building of staircases is time consuming, and hitherto, staircases have been generally made to measure by craftsmen usually on site. Indeed, it has been sometimes necessary to include one or more steps of different riser height to ensure that the staircase spans the required height. This is clearly unsatisfactory.

An object of this invention is to provide!, an improved frame and/or a demountable staircase, or which will at least provide the public with a useful choice.

According to a first broad aspect of the invention, there is provided a demountable staircase including: top and bottom mounting means; a plurality of stair treads mounted one each between a pair of stair tread support members; a plurality of pairs of stringer segments, each pair of stringer segments being pivotally connected at one end thereof to a respective one of said tread support members and at the other end thereof to an adjacent tread support member, and a plurality of bracing members, each bracing member being pivotally connected between adjacent tread members such that each pair of tread support members is disposed in substantially vertical spaced apart relationship to an associated pair of tread support members.

In a second broad aspect of the invention there is provided a demountable staircase pr terrace seating including, a pair of side frames with $t^ir treads attached at intervals to said side frames; each said side frame including a plurality of said support members, a plurality of pairs of stringer segments being pivotally connected at each end thereof to adjacent tread support members, and bracing members pivotally connected 194823 between adjacent tread support members, bottom mounting means anchoring a lower end of said side frame, and top mounting means anchoring a top end of said side frame, whereby relative movement of said top and bottom mounting means will enable the angle of said staircase and thus the vertical spacing between said treads to be adjusted in situ.

By constructing the framework from a plurality of pivotally connected relatively short members, the resulting framework can be adjusted by moving the top and bottom mounting means towards or away from one another either horizontally or vertically so that the span or height of the staircase can be adjusted without the need for interposing one or more steps of different riser heights. Thus, the adjustment allows a user to assemble a staircase framework, and to adjust it in situ.

Other aspects of this invention which should be considered in all its novel aspects will become apparent from the following description, which is given by way of example only, with reference to the accompanying drawings, in which: Figure 1 illustrates a front elevation of a staircase embodying the framework of this invention.

Figure 2 illustrates the staircase of Figure 1 in side elevation. Figure 3 illustrates an exploded view of the upper framework components.

Figure 4 illustrates an exploded view of the lower framework components.

A staircase 10 is constructed from a framework having a pair of side frames 11. Treads 12 span the side frames, with each tread resting on a 184823 pair of tread support members 13. Each side frame has bottom mounting means 14 and top mounting means 15.

The side frames can be constructed from a kitset consisting of a plurality of standard members, and these will be described with particular reference to Figures 3 and 4.

The basic components consist of the tread support members 13, and a plurality of stringer segments 16, 17. The tread support members 13, and the upper stringer segments 16, are of angle cross-section, whilst the lower stringer segments 17 are formed of flat strip. In addition, there are bracing members 18 capable of interconnecting adjacent tread support members, and alternate ends of the stringer segments to form diagonal bracing. The tread support members 13 are provided with connection apertures 20, one of which is preferably situated at the inner end of the vertical flange of the tread support members, whilst the second connection aperture 20 is provided about the mid portion of the tread support member, so that a portion of the tread support member will extend beyond the stringers of the side frame. Similar connection apertures 21, 22, are provided in each end of the upper and lower stringer segments 16, 17. The bracing members 18 are provided with a connection aperture 23 at one end, and an adjustment slot 2k at the other end thereof.

The lower mounting means 14 preferably includes height adjustment means e.g. a screw jack having an upper portion 25 attached to the lowermost tread support member, and a lower portion 26 attached to a mounting plate 27. 194523 The top mounting means 30 is in the form of an angle bracket having a tread support member 31 and a vertical member 32. As shown, the tread support member 31, is half the length of the tread support members 13, to provide a half step at the top of the framework. The vertical member 32 has an angle section similar to the cross-section of the tread support member 31, so that it has a flange capable of being attached to a vertical surface of a wall against which the staircase is mounted.

A connection aperture 33 and an adjustment slot 34 are provided in the top mounting means 30. In addition, a tie member 35 is provided for connection between the top mounting member and the uppermost tread support member 13. This tie member has a connection aperture 36 and an adjustment slot 37.

To facilitate the connection of adjacent upper stringer segments 16, it is preferred that alternate stringer segments 16 are provided with chamfered ends, so as to fit under the ends of the adjacent stringer segments. Thus, the stringer segments 16 are divided into "unders" 16a, 16c and "overs" 16b. The apertures 21 in the "unders" and "overs" are arranged so as to coincide when the staircase is assembled.

In use, a demountable staircase of any desired height can be constructed utilising the components of Figures 3 and 4. Thus, a five tread staircase, as shown in Figures 1 and 2, can be constructed as follows.

A pair of side frames 11 are constructed from the tread support members 13, stringer segments 16, 17 and bracing members 18. It is 184323 convenient to start from the lowermost tread support members 13, which is already provided with the bottom mounting means 14 attached thereto. Each side frame is assembled by interconnecting the various members with fasteners such as nuts and bolts, and leaving the fasteners 5 relatively loose, so that the framework can be adjusted. With a pair of side frames 11 loosely constructed, the desired step size is checked to suit the avilable height, one of the side frames is tightened; and the other is made identical. When assembled, the staircase can be raised into position and the top and bottom mounting means moved relative to one 10 another until the desired span and height is achieved. For example, the half step 31 can be provided below the top landing or' can be provided as an extension of the top landing. Final adjustment can be taken up by the lower screw jack 14 if necessary.

The staircase can be completed by attaching the treads. In the case of 15 a small staircase, the treads can be attached before raising it into position.

If desired, cross bracing can be provided to minimise sideways movement in larger staircases.

TO c a } ^ " Cr> Q) !• >- > $ ■5" i-j 8 » SJ a 3 ^ 1 1 1 It will be apparent from Figure 2 that riser boards can be fitted between 20 the treads 12 and paneling can be fitted to the side frames and to the underside of the staircase to substantially hide the framework.

Although not shown, a handrail can be readily fitted to the staircase by attaching handrail posts to the treads at suitable intervals. 1Q & f: o o JL v/ ti It will be appreciated that the demountable staircase lends itself to the provision of a kitset framework consisting of a plurality of metal members which, because of their relatively short lengths compared to the overall staircase, can be readily stored or transported, enabling a home handyman 5 to construct a staircase to his own requirements by purchasing such a kitset framework, and purchasing the required number of treads. The components for Figures 3 and 4 can be purchased in kitset form and erected to provide, for example, a five tread demountable staircase. The nature of the demountable staircase provides that, should the staircase be 10 repositioned or its incline altered, extra tread support members 13, stringer segments 16, 17 and bracing members 18 can be incorporated into the staircase or one or more sets of the components can be removed as required.

I Instead of providing a pair of tread support members for each tread, it 15 will be appreciated that the tread support members can be formed integral with a tread, e.g. a metal tread having side flanges forming the tread support members. This, however, is not as versatile as the pair of tread support members illustrated, as the pair of tread support members enables a stair tread of any desired width to be utilised with 20 the staircase framework. Moreover, the illustrated framework enables a series of side frames to be positioned side by side to support treads of relatively great width, e.g. as used for terrace seating. £ 1 Finally, it will be appreciated that various alterations or modifications ^ { O t may be made to the foregoing without departing from the scope of this S in. " b <j-» s • r;;| |25 invention as exemplified by the following claims.

Claims (8)

194823 8 - WHAT T CLAIM IS;

1. A demountable staircase including; top and bottom mounting means; a plurality of stair treads mounted one each between a pair of stair tread support members; a plurality of pairs of stringer segments, each pair of stringer segments 5 being pivotally connected at one end thereof to a respective one of said tread support members and at the other end thereof to an adjacent tread support member, and a plurality of bracing members, each bracing member being pivotally connected between adjacent tread support members such that 10 each pair of tread support members is disposed in substantially vertical spaced apart relationship to an associated pair of tread support members.

2. A demountable staircase as claimed in claim 1, wherein said tread support members are formed of angle section members.

3. A demountable staircase as claimed in claim 2, wherein said tread support members and said stringer segments are provided with connection apertures which receive removable fasteners, and said bracing members are provided with a connection aperture at one end thereof and an adjustment slot at the other end thereof.

4. A demountable staircase as claimed in claim 3,wherein each said tread support member has a portion extending 15 _ 9 - 194823 beyond said connection apertures, which protrudes from the stringer segments o£> the staircase.

5. A demountable staircase as claimed in claim 4, wherein said top mounting means consists of an angle bracket having a tread support member approximately half the length of the aforesaid tread support members, and a vertical limb capable of being attached to a vertical surface.

6. A demountable staircase as claimed in claim 5, wherein said bottom mounting means includes a height adjustment means.

7. A staircase or terrace seating including; a pair of side frames with stair treads attached at intervals to said side frames; each said side frame including a plurality of tread support members; a plurality of pairs of stringer segments, each pair of stringer segments being pivotally connected at each end thereof to adjacent tread support members, and bracing members pivotally connected between adjacent tread support members, bottom mounting means anchoring a lower end of each side frame, and top mounting means anchoring a top end of each side, frame; whereby relative movement of said top and bottom mounting means will enable the angle of said staircase and thus the vertical spacing between said treads to be adjusted in situ. - 10 -

8. A demountable staircase substantially as herein described with reference to the accompanying drawings. PETER WILMONT SETON