US3839840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of erecting stairs
Assignee: PARKER C CO
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Filing: 1973-04-30
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Granted: 1974-10-08
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Expires: 1993-04-30
Abstract
Abstract The invention contemplates a metal-stair construction wherein a succession of interrelated tread and riser elements derive support from an elongate lower flange of a course-defining stringer; once thus supported, the individual tread and riser elements are secured at their ends to the primary face or panel of the flange-bearing stringer. In the form disclosed, a suitably formed retaining lip along the upper forward edge of each tread provides a means for applying hardenable tread material to the horizontal volume above the tread element and bounded by adjacent vertical walls of the lip, riser and stringer.
Inventors
- 👤 C Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:51
CPC Classifications
E; E04; E04F; E04F11/00; E04F11/02; E04F11/022; E04F11/025
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
251 words
The method of erecting stairs along a sloping course between supporting members at each of two levels to be stair-connected, which comprises selecting a pair of stringers adapted to span said course and to be supported by said members, each stringer having a primary panel with an elongate stair-supporting flange along a lower edge, erecting said stringers on said supporting member and in desired spaced relation, with said flange oriented along the lower limit and alignment of said course, selecting duplicate stair tread and riser elements of length to match said spacing, each tread and riser element being additionally selected for an upstanding tread-retaining flange-lip formation along the upper edge of the riser portion thereof, assembling tread and riser elements to the flanges of said stringers such that the intersection edge between each tread element and the next-above riser element is abutted to and supported by both flanges, with ends of said tread and riser elements adjacent the respective panels of said stringers, the tread portion of each element being so supported by the riser portion of the next lower element that the flange-lip formation projects upwardly of the elevation of the tread portions, thereby defining a fillable tread volume beneath a horizontal plane at the upper edge of said flange-lip formation, welding end portions of said tread and riser elements to the immediately adjacent regions of said panels, such welding for each element being limited to regions within said volume, and applying a hardenable tread material into each said volume.
Claim 2
Independent Claim
251 words
The method of erecting stairs along a sloping course between supporting members at each of two levels to be stair-connected, which comprises selecting a pair of stringers adapted to span said course and to be supported by said members, each stringer having a primary panel with an elongate stair-supporting flange along a lower edge, erecting said stringers on said supporting member and in desired spaced relation, with said flange oriented along the lower limit and alignment of said course, selecting duplicate stair tread and riser elements of length to match said spacing, each tread and riser element being additionally selected for an upstanding tread-retaining flange-lip formation along the upper edge of the riser portion thereof, assembling tread and riser elements to the flanges of said stringers such that the intersection edge between each tread element and the next-above riser element is abutted to and supported by both flanges, with ends of said tread and riser elements adjacent the respective panels of said stringers, the tread portion of each element being so supported by the riser portion of the next lower element that the flange-lip formation projects upwardly of the elevation of the tread portions, thereby defining a fillable tread volume beneath a horizontal plane at the upper edge of said flange-lip formation, welding end portions of said tread and riser elements to the immediately adjacent regions of said panels, such welding for each element being limited to regions within said volume, and applying a hardenable tread material into each said volume.
Claim 3
Independent Claim
205 words
The method of erecting stairs along a sloping course between supporting members at each of two levels to be stair-connected, which comprises selecting a pair of stringers adapted to span said course and to be supported by said members, each stringer having a primary panel with an elongate stair-supporting flange along a lower edge, such stringer selection additionally involving a vertical-reference flange at the lower end of each panel, erecting said stringers on said supporting member and in desired spaced relation, with said flange oriented along the lower limit and alignment of said course, selecting stair tread and riser elements of length to match said spacing, assembling tread and riser elements to the flanges of said stringers such that the intersection edge between each tread element and the next-above riser element is abutted to and supported by both flanges, with ends of said tread and riser elements adjacent the respective panels of said stringers, and securing end portions of said tread and riser elements to the immediately adjacent regions of said panels, the lowermost riser element being first secured to said vertical-reference flange, and the next tread element being supported by said first riser element and by said stair-supporting flanges when secured to said panels.
Claim 4
Independent Claim
205 words
The method of erecting stairs along a sloping course between supporting members at each of two levels to be stair-connected, which comprises selecting a pair of stringers adapted to span said course and to be supported by said members, each stringer having a primary panel with an elongate stair-supporting flange along a lower edge, such stringer selection additionally involving a vertical-reference flange at the lower end of each panel, erecting said stringers on said supporting member and in desired spaced relation, with said flange oriented along the lower limit and alignment of said course, selecting stair tread and riser elements of length to match said spacing, assembling tread and riser elements to the flanges of said stringers such that the intersection edge between each tread element and the next-above riser element is abutted to and supported by both flanges, with ends of said tread and riser elements adjacent the respective panels of said stringers, and securing end portions of said tread and riser elements to the immediately adjacent regions of said panels, the lowermost riser element being first secured to said vertical-reference flange, and the next tread element being supported by said first riser element and by said stair-supporting flanges when secured to said panels.
Claim 5
Dependent Claim
54 words
The method of claim 2, wherein stair and tread elements above said lowermost riser element are selecTed as duplicate units, each unit comprising a tread element integrally formed with the next-above riser element, each unit tread element being supported by the next-lower riser element and by said stair-supporting flanges when secured to said panels.
Claim 6
Dependent Claim
85 words
The method of claim 3, wherein said units each are additionally selected for a tread-retaining flange-lip formation along the upper edge of the riser element thereof, each unit tread element being so supported by the next-lower riser element that the retaining lip formation projects upwardly of the tread-element elevation, and applying a hardenable tread material into the upwardly open volume defined by each tread element and the horizontal intercept of the upper edge of the associated retaining lip with the adjacent panels and next-above riser.
Claim 7
Dependent Claim
42 words
The method of claim 2, wherein the stringer selection additionally involves a vertical-reference flange at the upper end of each panel, the uppermost riser element being abutted to said upper vertical-reference flange and to said stair-supporting flanges when secured to said panels.
Claim 8
Dependent Claim
47 words
The method of claim 2, wherein the stringer selection additionally involves a tread-supporting horizontal-reference flange at the upper end of each panel, the tread-supporting flange and the tread-supporting region of the uppermost riser element being horizontally aligned when said uppermost riser element is secured to said panels.
Claim 9
Dependent Claim
65 words
The method of claim 2, wherein the stringer selection additionally involves horizontal and vertical reference flanges at the upper end of each panel; the uppermost riser element being abutted to said upper vertical-reference flange and to said stair-supporting flanges, and the tread-supporting region of the uppermost riser element being horizontally aligned with said horizontal flange, when the uppermost riser element is secured to said panels.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-07 | 1978-04-08 | 1978-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-07 | 1982-04-08 | 1982-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-07 | 1986-04-08 | 1986-10-08 | $7700.00 | Window Closed / Lapsed |