EP0178773A1
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Suspension ladder
Assignee: Greywill Mill Ltd Te Farnham Groot-Brittannie
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Filing: 1985-09-06
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Granted: —
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Expires: 2005-09-06
Abstract
Abstract A suspension ladder comprises a string of identical rigid rectangular sections (1) which are hinged together about a series of parallel axes adjacent their longer rear edges (2), and each of which has one or more apertures (11) forming a rung of the ladder. Each section (1) has a trapezoidal cross sectional profile providing the section with sloping top and bottom edge faces (4) and (5) which converge towards the front face (6) from the longitudinal rear edges (2) and form stops which limit the extent to which adjoining sections can pivot towards each other in a forward direction. The ladder therefore cannot be flexed in this direction beyond a predetermined minimum radius of curvature and will therefore form a substantially rigid cradle (21) when its lower end is lifted while its upper end is suspended. In contrast adjacent sections can pivot flat against each other in the rearward direction so that the ladder can be rolled up tightly for easy storage.
Inventors
- 👤 Nigel Clive Watling
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 01:32
CPC Classifications
E; E06; E06C; E06C1/00; E06C1/52; B; B63; B63B; B63B27/00; B63B27/14; B63C; B63C9/00; B63C9/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
89 words
A suspension ladder characterized in that the ladder comprises a string of substantially rigid sections (1) which form the rungs of the ladder and which are hinged together about a series of parallel axes so that the ladder is flexible in the plane perpendicular to the axes, and stops (4, 5 ) for limiting the extent to which adjoining sections can pivot towards each other on one side of the ladder so that the ladder cannot be flexed on this side beyond a predetermined minimum radius of curvature .
Claim 2
Dependent Claim
89 words
A suspension ladder characterized in that the ladder comprises a string of substantially rigid sections (1) which form the rungs of the ladder and which are hinged together about a series of parallel axes so that the ladder is flexible in the plane perpendicular to the axes, and stops (4, 5 ) for limiting the extent to which adjoining sections can pivot towards each other on one side of the ladder so that the ladder cannot be flexed on this side beyond a predetermined minimum radius of curvature .
Claim 3
Dependent Claim
20 words
A ladder according to Claim 1, in which the predetermined minimum radius of curvature is between 0.25 and 0.40 metres.
Claim 4
Dependent Claim
52 words
A ladder according to Claim 1 or Claim 2, in which the stops comprise surfaces (4, 5) on each pair of adjoining sections (1) which are arranged to engage each other when the sections are pivoted towards each other on the one side of the ladder and reach a predetermined included angle.
Claim 5
Dependent Claim
46 words
A ladder according to any one of the preceding Claims, in which the included angle between adjoining sections (1) at which the stops (4, 5) prevent further pivoting of the sections towards each other on the one side of the ladder is between 150° and 170°.
Claim 6
Dependent Claim
53 words
A ladder according to any one of the preceding Claims, in which the sections (1) are hinged together so that adjoining sections are capable of pivoting to a position in which they lie substantially flat against each other on the opposite side of the ladder from that on which the stops are operative.
Claim 7
Dependent Claim
58 words
A ladder according to Claim 5, in which adjoining sections (1) are hinged together by a hinge comprising a pair of interconnected parallel hinge pins (11), one of which is received rotatably in a socket (9) in one of the sections (1), and the other of which is received rotatably in a socket (9) in the other section.
Claim 8
Dependent Claim
21 words
A ladder according to any one of the preceding Claims, in which the sections (1) are substantially identical to each other.
Claim 9
Dependent Claim
26 words
A ladder according to Claim 7, in which each section (1) is rectangular and has at least one aperture (11) defining a rung of the ladder.
Claim 10
Dependent Claim
37 words
A ladder according to Claim 8, in which each section (1) has two apertures (11) separated by a central portion (12) which is parallel to the side edges of the section and perpendicular to the hinge axes.
Claim 11
Dependent Claim
38 words
A ladder according to Claim 8 or Claim 9, in which each section has a trapezoidal cross-sectional profile in the plane perpendicular to the hinge axes whereby the sloping faces (4, 5) of the section form the stops.
Claim 12
Dependent Claim
80 words
A ladder according to Claim 10, in which each section (1) comprises an extruded length of aluminium or plastics having a longitudinal bore (9) adjacent each longitudinally extending rear edge (2), and adjoining sections (1) are connected by hinge pins (13) which are inserted into the bores (9) adjacent the junction between the sections and which are interconnected by links (14) so that each section is able to rotate on its hinge pin (13) but not to slide along it.
References Cited (Backward Citations)
US2527995A
Cited
DE3014210A1
Cited
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