Patent US3916591A successfully refreshed from Google Patents.
US3916591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spindle staircase
Assignee: GIETERIJ DOESBURG BV
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Filing: 1974-03-13
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Granted: 1975-11-04
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Expires: 1994-03-13
Abstract
Abstract Conventionally a spindle staircase is mounted in the building in the course of construction so that fine, for example, hard-wood steps may be damaged or be at least soiled with building material on account of rough treatment. Cleaning of the steps requires much labour and time. If during the building operations steps are damaged, they have to be replaced by new ones, resulting in high costs. These problems are avoided by first fastening provisional step units formed each by a working step and a step support secured thereto in a detachable manner to the spindle and by replacing these provisional step units afterwards by new ones.
Inventors
- 👤 Henk Agterhof
- 👤 Johannes Antony Dewaal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:04
CPC Classifications
E; E04; E04F; E04F11/00; E04F11/02; E04F11/022; E04F11/032
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
130 words
A spindle staircase comprising: a. a spindle having a plurality of spindle sections; b. a step holder attached to at least some of said spindle sections, said step holder having an elongated, three-sided gutter and tongue-like cam; c. a detachable step support having a bar and integral bridge piece, said bar being received in said step holder gutter and fitting with said cam; d. means for locking said bar in said gutter; and e. a step connected to said step support by screws hidden from view at the top side of the step; whereby said step support with connected step is easily removable by releasing the means for locking, and said step may be conveniently replaced by mounting a new step to said step support at a convenient work area.
Claim 2
Dependent Claim
130 words
A spindle staircase comprising: a. a spindle having a plurality of spindle sections; b. a step holder attached to at least some of said spindle sections, said step holder having an elongated, three-sided gutter and tongue-like cam; c. a detachable step support having a bar and integral bridge piece, said bar being received in said step holder gutter and fitting with said cam; d. means for locking said bar in said gutter; and e. a step connected to said step support by screws hidden from view at the top side of the step; whereby said step support with connected step is easily removable by releasing the means for locking, and said step may be conveniently replaced by mounting a new step to said step support at a convenient work area.
Claim 3
Dependent Claim
20 words
A spindle staircase as claimed in claim 1 in which said step holder and attached spindle are an integral casting.
Claim 4
Dependent Claim
42 words
A spindle staircase as claimed in claim 1 in which said step holder is detachably connected to said spindle sections by recesses on said step holder and matching pins on said spindle section, said recesses and pins being locked together by screws.
Claim 5
Dependent Claim
176 words
A spindle staircase comprising: a. a spindle having a plurality of spindle sections, at least some of which have a first channel section connection element as an integral part thereof; b. a step holder having a gutter and a second channel section connection element, said first and second channel section elements mating and being locked together by a single locking screw to form a detachable connection between said step holder and said spindle sections with first channel section elements; c. a step support having a bar and a transverse metal strip at one end thereof said bar being received in said step holder gutter; and d. a step connected to both said metal strip of the step support and said step holder by screws hidden from view at the top side of said step; whereby said step holder with attached step and step support is easily detachable by removing said locking screw, and said step may be easily replaced by mounting a new step to said step support and step holder at a convenient work area.
Claim 6
Dependent Claim
176 words
A spindle staircase comprising: a. a spindle having a plurality of spindle sections, at least some of which have a first channel section connection element as an integral part thereof; b. a step holder having a gutter and a second channel section connection element, said first and second channel section elements mating and being locked together by a single locking screw to form a detachable connection between said step holder and said spindle sections with first channel section elements; c. a step support having a bar and a transverse metal strip at one end thereof said bar being received in said step holder gutter; and d. a step connected to both said metal strip of the step support and said step holder by screws hidden from view at the top side of said step; whereby said step holder with attached step and step support is easily detachable by removing said locking screw, and said step may be easily replaced by mounting a new step to said step support and step holder at a convenient work area.
Claim 7
Dependent Claim
122 words
A spindle staircase comprising: a. a spindle having a plurality of spindle sections; b. a step holder attached to at least some of said spindle sections, said step holder having an elongated, three-sided gutter; c. a detachable step support having a bar and integral bridge piece, said bar being received in said step holder gutter; d. means for locking said bar in said gutter; and e. a step connected to said step support by screws hidden from view at the top side of the step; whereby said step support with connected step is easily removable by releasing the means for locking, and said step may be conveniently replaced by mounting a new step to said step support at a convenient work area.
Claim 8
Dependent Claim
122 words
A spindle staircase comprising: a. a spindle having a plurality of spindle sections; b. a step holder attached to at least some of said spindle sections, said step holder having an elongated, three-sided gutter; c. a detachable step support having a bar and integral bridge piece, said bar being received in said step holder gutter; d. means for locking said bar in said gutter; and e. a step connected to said step support by screws hidden from view at the top side of the step; whereby said step support with connected step is easily removable by releasing the means for locking, and said step may be conveniently replaced by mounting a new step to said step support at a convenient work area.
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) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |