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US4027855A
Expired / Lapsed
US
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Guard rail
Assignee: CENTRAL AUTOMOBILE INDUSTRY Co Ltd
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Filing: 1976-02-02
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Granted: 1977-06-07
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Expires: 1996-02-02
Abstract
Abstract Guard rail having an inclined rail, for staircase or access stairway. The rails are essentially constituted by U-shaped profile sections. The vertical rails are fixed on the rails by elastic clipping action between the flanges of the profile sections. The notches made in the vertical bars to provide this clipping action are incurvate, which makes it possible to adapt one and the same guard rail to variable angles of inclination of the handrail.
Inventors
- 👤 Rene Lauzier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:57
CPC Classifications
E; E04; E04F; E04F11/00; E04F11/18; E04F11/181; E04F11/1842; E04F11/1844; E04F11/1817; E04F2011/1823; E04F2011/1825; E04F2011/1827; F; F16; F16B; F16B2200/00; F16B2200/10; F16B2200/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
247 words
Guard rail comprising an inclined handrail and vertical bars of a width L in the plane of the guard rail and which forms with the horizontal an angle capable of varying between two limits α-δα and α+δα, the said handrail being itself essentially constituted by an open profile section of generally U-shaped cross-section in which the side walls of the profile extend in the direction away from the handrail and with the web of the profile being of a thickness l, ribs extending inwardly from said side walls, perforations in the web of the hand rail dimensioned to allow the ends of the vertical bars to traverse the said web, at least one notch in the end portion of said vertical bar to be secured by clipping on ribs extending inwardly from the side walls of the handrail, said guard rail being characterized in that on the one hand the perforations in the web of the hand rail have in the plane of the guard rail a horizontally measured width L + e (tgδα/cosα) and in that, on the other, the bearing surface of each notch on the corresponding rib of the rail is defined by a surface of revolution tangent to the bearing surface of the rib, the axis of this surface of revolution being at right-angles to the plane of the guard rail and traversing this plane beyond the rail with respect to the portion of the plane in which the vertical bars are located.
Claim 2
Dependent Claim
247 words
Guard rail comprising an inclined handrail and vertical bars of a width L in the plane of the guard rail and which forms with the horizontal an angle capable of varying between two limits α-δα and α+δα, the said handrail being itself essentially constituted by an open profile section of generally U-shaped cross-section in which the side walls of the profile extend in the direction away from the handrail and with the web of the profile being of a thickness l, ribs extending inwardly from said side walls, perforations in the web of the hand rail dimensioned to allow the ends of the vertical bars to traverse the said web, at least one notch in the end portion of said vertical bar to be secured by clipping on ribs extending inwardly from the side walls of the handrail, said guard rail being characterized in that on the one hand the perforations in the web of the hand rail have in the plane of the guard rail a horizontally measured width L + e (tgδα/cosα) and in that, on the other, the bearing surface of each notch on the corresponding rib of the rail is defined by a surface of revolution tangent to the bearing surface of the rib, the axis of this surface of revolution being at right-angles to the plane of the guard rail and traversing this plane beyond the rail with respect to the portion of the plane in which the vertical bars are located.
Claim 3
Dependent Claim
80 words
Guard rail according to claim 1, characterized in that the perforations in the web of the hand rail are preferably made in the plane of the guard rail obliquely with respect to the web of the hand rail, the axis of the perforations making with the axis of the rail the complementary angle to the angle α, the width of these perforations measured perpendicularly to their axis and in the plane of the guard rail being L + e (tgδα/cosα).
Claim 4
Dependent Claim
85 words
Guard rail according to claim 1, of which each vertical bar comprises on the side facing the side wall of the hand rail only a single incurvate notch, characterized in that the surface of revolution defining the supporting surface of the notch is a cylinder of revolution tangent to the bearing surface of the corresponding limit according to a generatrix which cuts the axis of the vertical bar, when this latter is in the position corresponding to the mean angle of inclination of the handrail.
Claim 5
Dependent Claim
61 words
Guard rail according to claim 3, characterized in that the cylinder of revolution limiting the supporting surface of the incurvate notch is of a radius equal to or greater than that determined by the laws of resistance of the materials, the deformation of the materials constituting the notch and the corresponding rib being required not to exceed the admissible elastic limit.
Claim 6
Dependent Claim
76 words
Guard rail according to claim 1, characterized in that in the plane of the guard bar each vertical rail has a width equal to or greater than that in which the projections of all the points of contact between notch and rib are inscribed when the vertical bar is positioned according to one or other of the extreme angles about the mean angle and when the said vertical rail is subject to the maximum transverse strain.
Claim 7
Dependent Claim
151 words
Guard rail according to claim 1 of which each vertical bar comprises at least on a face facing each side wall of the hand rail a plurality of successive incurvate notches, characterized in that these notches have their bearing surfaces defined by coaxial cylinders perpendicular to the plane of the guard rail and of which the common axis cuts the said plane at a point on the perpendicular raised in the plane of the guard rail to the supporting surface of an imaginary rib disposed between the existing ribs, the said perpendicular passing through the intersection of the plane of the imaginary rib and the axis of the vertical bar, the minimum radius of the coaxial cylinders and the width of the vertical bar in the plane of the guard rail being defined by the laws of resistance of the materials as a function of the elastic limit of the materials.
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) | 1980-06-06 | 1980-12-06 | 1981-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-06 | 1984-12-06 | 1985-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-06 | 1988-12-06 | 1989-06-07 | $7700.00 | Window Closed / Lapsed |