US2448264A - Steel stairway - Google Patents

Description

Aug. 31, 1948. E. A. JUNG 2,448,264

' STEEL sTAIRwAY f Filed NOV. 29, 1945 "TU 5 n? f' 3562 42 25 lIll INVENTOR.

E27-Z Jui?? '-f ,BYW L 1:9 @y/w 4 Patented Aug. 31,y 1948 UNITED STATES PATENT OFFICE STEEL sTAmWAY Earl A. Jung, Buffalo, N. Y., assigner to August Feine & Sons Co., Buffalo, N. Y.

Application November 29, 1945, Serial No. 631,522

3 Claims. (Cl. 189-43) This invention relates to a structural steel stairway, vand it has particular reference to the provision of" an integrated and welded stairway, in which the Stringer, tread, and landing portions thereof will be free from excessive strains, will be of adequate strength to take all intended loads, and will be so organized and interconnected as to be free from the destructive effects of the elements and corrosion.

Stairwaysl of the typeherein considered nd especial utility as fire escapes for buildings of various types, and as inside or outside stairways for factories, mills, and similar industrial structures. In them, the' attainment of certain attributes is highly desirable. They should be so constructed as to have sucient strength for the relatively heavier loads imposed on them than on residential or oce stairs; their tread and landing areas should provide some factor of safety against slipping by burdened workmenor panicky persons seeking to escape from a burning building; they should havea long life andl require a minimumv of inspection and maintenance. The stairway of the present invention has been invented with these objectives in mind, has been tested by use and exposure, and has been found to satisfy the requirements and regulations of building codes and `safety bureau inspections.

One of the most fertile sources of trouble with industrial stalrways has been corrosion, caused either by exposure to the weather,or by accumulations of waste material and dirt-around joints or crevices. This condition is not, as a practical vproposition-entirely counteracted by inspection, or by attempts to have workmen clean the metal periodically. It is well understood that many owners `will resort to a ,bit of paint to conceal a weakened point from a civic inspector, rather than make extensive and costly repairs either voluntarily or by compulsion.

, Corrosion will continue under such a covering, and of course during the intervals between inspections or-repairs. While the actualextent of deterioration may be small overa period of a few months, the progressive action nevertheless impairs the safety of the stairway against the emergencywhen safety will be most essential; aswell as `causing an economic loss. By the present invention, it is proposed to have a stairway 4which is as self-cleaning as.possib1e,so that 2 dirt, ice, moisture, and the like cannot accumulate to cause corrosion. With such construction, the maintenance is reduced to the customary painting required for exposed steel work;` and the life of the stairway is correspondingly extended. l

A practical way in which the objects of the invention may be achieved will be setiforth in the following description, read in connection with the accompanying drawing, wherein:

Fig. 1 is a longitudinal section taken through the tread and landing portions of vthe stair- Way;

Fig. 2 is a section taken substantially along the line 2--2 of Fig. 1;

Fig. 3 is a plan, with portions broken away, of' a landing; and,

Fig. 4 is a plan of a tread, portions of the adjoining stringers being shown in section. p

The stairway comprises a pair of spaced stringers Ill and ll, inclined at such angle as is appropriate for the rise and run, and between which extend any suitable number of treads l2. The treads lead between landings, generally designated by the reference numeral i3, and while only one landing is illustrated in the drawing, it will be understood that another may be placed at the foot, or between two flights, in accordance with common practice.

It will be seen that each tread l2 is formed from a unitary metal plate Whose body portion is punched to provide rows and columns of openings |4 surrounded by solid metalsections I5 and is. The front and back edges of the tread may also be turned down and given a slight inward curl, as indicated by the flanges I1 and I8 in Figs. 1 and 4. The punched openings I4 not only serve to lessen the total weight of the tread, without unduly weakening the structure, but also provide a satisfactory measure of anti-skidy or gripping surface. They also have another function, which will be referred to subsequently. By providing the anges l1 and I8, a protective strip is included to safeguard theusers shins from annoying bumps or cuts, and these flanges moreover add to the strength. y

The ends of the treads are also cut away, as by a punching operation, to provide spaced ears 2| of equal length which delimit an opening 22 adjacent the Stringer I0 or Il. When the night is fabricated in the shop or erected in the field, the ears '2l are welded to the stringers throughout the contacting and abutting areas, and insofar as the fianges I1 and IB are continuous with the ears, and also abut the stringere, the welding is also continued throughout these areas. In the figures, the welded portion is illustrated by an irregular line, indicating the surfaces over which the operation is performed.

A very significant advantage is obtained by following these principles is assembly. For all practical purposes, the contacting areas are integrated to each other, and are therefore free from joints, cracks, or crevices capable of holding moisture or dirt, and therefore developing any electro-corrosive actions. The upper surfaces of the ears are quite limited, particularly as compared with the extent of the openings 22, and therefore the quantity of dirt or ice or water which can be supported on, or retained by, the'.

angle between the stringere and treads, is practicallv negligible. The tread is therefore selfcleaning, in the sense that it is so organized that very little refuse of any kind will remain on it f irrespective of the matter of periodic brushing or sweeping. The openings I4, previously referred to, also provide for the elimination of dirt or water.

It will be seen that the stringers are shown as being formed of flat stock, rather than the more common channel section stock. This is because the welding of the treads to the stringers provides a measure of increased strength, not obtainable with the former bolted or riveted types of stairs. For comparable loads and service conditions, the stringers may therefore be made of lighter and less expensive material.

The landing I3 is made, as far as practical, the same Way as the treads I2, but With a few modifications as may be desired to meet the exigencies of various installation problems. As shown in Figs, 2 and 3, the landing illustrated therein and in Fig. 1 comprises two grate members 23 and 24 of similar construction. Each consists of a body portion formed with columns and rows of openings 25, as described in connection with the treads I2, and with spaced side flanges 25 and 21. In the specific stairway illustrated, the lay-out is such that there is no need for the ears 2I or their counterparts, inasmuch as the grates extend in the same direction as the run of the flight itself. To support the landing, an angle iron 28 is shown as extending between and welded to the upper portions of the stringers I 0 and Il, to serve as a beam for the front edge of the flanges 26. The contacting areas between these flanges and the stringers are also welded, so as to exclude corrosive materials, as previously explained, The rear edges of the fianges 26 may be similarly supported on a beam, as shown by the cross member 29 in Fig. 1.

When the distance between the beams 28 and 29 is appreciable, as compared to the distance between the stringers, and a number of grates are required for the width of the stairway, there may b-e some tendency for the grates to sag as the loads are applied and released irregularly upon them. This tendency is met by providing an interlocking connection between the grates, so as to distribute the loads between them. As best shown in Figs. 2 and 3, the flanges 21 of the grates 23 and 24 have welded to them, at spaced intervals, angle blocks 3l and 32 having one flange or face welded to the inner face of the grate fiange, while the other flange or face of the block extends outwardly therefrom and parallel to the working surface of the grate. These angle blocks may be divided between the adjacent grates 23 and 24, so that a block extending from the grate 23 underlies the flange 21 of the adjoining grate 24, and, in like fashion, the flanges of the blocks secured to the grate 24 underlie the grate 23.

It will be seen that if a heavy load should be imposed on the grate 23, for example, the resulting deflection would cause its side flange 21 to engage the blocks 3| on the adjoining grate 24, and thus distribute part of the load to the grate 24. Thus, any excessive tendency toward deflection is counteracted by the interconnection, under stress conditions, of the grates making up the entire landing.

It will also be seen that, for many purposes, the. grates' of the landing may be used as treads, while thel tre-ads may be used to forni grates. This is readily accomplished by removing the ears 2l, or the blocks 3I or 32, in the event they are not required, or by utilizing them for their full Vpurposes if the building under consideration so permits. For example, in a, short landing between flights, a number of treads I2 may be welded in place with their load-receiving surfaces in the same plane, and if the width of the stair should be more than that commonly encountered, then the angle blocks would be applied to the flanges. I1 and I8. The flexure of the lgrates. 23 and 24, under the conditions just described, will impose. some movement over the contacted surfaces of theblocks 3l and 32, and thus shake off excessive accumulations o-f dirt whichV might otherwise be conducive to corrosion.

In actual service, it will be frequently advisable to erect a hand rail alongI one or both sides of the stairway, and this can be done by welding the rail to baluster pieces, in turn welded to the stringers or landing stag-es. As suchaa rail does not form a material Apartof this invention, and may be omitted altogether in some instances, it has been deemed unnecessary to illustrate one.

While the invention has been described with reference-to a specific embodiment thereof which has been tested under a variety of service conditions, and is therefore known to be apractical way to utilize the invention, it should be understood that the principles of the invention may be employed with various modifications, as fall within the scope of the following claims.

I cla-im:

1. In a, structural steel stairway having spaced stringers between which are vdisposed treads, tread members formed of fiat stock punched to provide a plurality of openings .over the working surface of the tread, ears projecting from the ends of the tread adjacent the side edges thereof, said ears abutting the inner surfaces of the stringers, and welded connections between the ears and said surfaces.

2. In a structural steel stairway, a pair of spaced stringers, treads positioned between the stringers and welded thereto, each of said treads being formed of flat stock having openings in the working surfacethereof, a flange :along the front side of the stock, ears projecting from each end of the tread vadjacent the corners of the stock and abutting the inner surfaces of the stringers, and welded connections between the abutting surfaces of the stringers and the ears and flange, the space rbetween the ears on each end and the adjacent Stringer being open to permit the free passage of moisture and dirt.

3. In a structural steel stairway, a pair 'of loadreceiving tread members having working surfaces disposed in the same plane, each of said members having a substantially plane body portion formed with a plurality of openings over the working surface thereof, flanges extending downwardly from said Working surface along the adjacent edges of the tread members, and angle blocks connected in spaced relation to both of said anges, said angle blocks having one face connected to one of said flanges and the other face underlying and contacting the flange of the adjacent member. l

EARL A. JUNG.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS

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