US4177879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ladder and method of construction therefor
Assignee: Emerson Electric Co
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Filing: 1977-07-25
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Granted: 1979-12-11
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Expires: 1997-07-25
Abstract
Abstract A ladder with elongated side rails each with a web with two broad surfaces, and rungs supported by and extending between the webs of the side rails at spaced locations, has rung brackets molded into and embracing the webs, each of the rung brackets having a rung receiving boss and a base part on one broad surface of the web and a pad part on the other broad surface, and tying members, integral with the base and pad parts, connecting the parts and extending into the web. In making the ladder, holes are formed in the webs at the rung locations and the rung brackets are molded in place in and through those holes.
Inventors
- 👤 William H. Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:34
CPC Classifications
E; E06; E06C; E06C7/00; E06C7/08; E06C7/082; E06C7/087
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
188 words
In a ladder having two elongated side rails each with a web, said web having two broad surfaces with spaced holes, said spaced holes including a large, central rung receiving hole in it, and smaller holes spaced outwardly from said central hole, and rungs supported by and extending between the webs of said side rails at spaced locations, the improvement comprising a rung bracket molded in place on said web having on one side of said web a hollow, rung receiving boss and a base part, and on another side of said web, a pad part, said pad and base parts covering all of said small holes, and tying members integral with the base and pad parts connecting said parts and extending through said holes in said web, said tying members of said bracket extending through all of said smaller holes and defining ribs extending from said base part to said boss, individual ones of said ribs being at least in part congruent with individual ones of said smaller holes so that said bracket is moldable in place on said web from a single side of said web.
Claim 2
Dependent Claim
188 words
In a ladder having two elongated side rails each with a web, said web having two broad surfaces with spaced holes, said spaced holes including a large, central rung receiving hole in it, and smaller holes spaced outwardly from said central hole, and rungs supported by and extending between the webs of said side rails at spaced locations, the improvement comprising a rung bracket molded in place on said web having on one side of said web a hollow, rung receiving boss and a base part, and on another side of said web, a pad part, said pad and base parts covering all of said small holes, and tying members integral with the base and pad parts connecting said parts and extending through said holes in said web, said tying members of said bracket extending through all of said smaller holes and defining ribs extending from said base part to said boss, individual ones of said ribs being at least in part congruent with individual ones of said smaller holes so that said bracket is moldable in place on said web from a single side of said web.
Claim 3
Dependent Claim
18 words
The improvement of claim 1 wherein said rung receiving boss has a non-circular rung receiving opening in it.
Claim 4
Dependent Claim
58 words
The improvement of claim 1 wherein said rung receiving boss has a rung receiving opening defined by a wall which diverges in the direction toward the pad part, further including an integral end of said rung in said opening, and adhesive in the space between the divergent wall of said boss and the integral end of said rung.
Claim 5
Dependent Claim
57 words
The improvement of claim 1 wherein each of said rungs have a first end and a second end, said first and second ends having a rectangular shape in plan, a first side of said rectangular shape having a locating means formed along it, the boss of said bracket having a notch sized to receive said locating means.
Claim 6
Dependent Claim
182 words
In a ladder having two elongated side rails each with a web, said web having two broad surfaces with spaced holes in them, said spaced holes including a central rung receiving hole and smaller holes spaced outwardly from said central hole and rungs supported by and extending between the webs of said side rails at spaced locations, the improvement comprising a rung receiving bracket molded in place on said web having on one side of said web means for interconnecting said bracket with said rung including a boss extending in a direction outwardly of said web and a base part, and on the other side of said web, a pad part, and tying members integral with said base and pad parts, said tying members connecting said base and said pad parts and extending through the smaller holes in said webs, said tying members defining support means integrally formed with the boss of said interconnecting means, said tying members and said smaller holes being arranged so that the bracket is moldable in place on said web from a single side of said web.
Claim 7
Dependent Claim
182 words
In a ladder having two elongated side rails each with a web, said web having two broad surfaces with spaced holes in them, said spaced holes including a central rung receiving hole and smaller holes spaced outwardly from said central hole and rungs supported by and extending between the webs of said side rails at spaced locations, the improvement comprising a rung receiving bracket molded in place on said web having on one side of said web means for interconnecting said bracket with said rung including a boss extending in a direction outwardly of said web and a base part, and on the other side of said web, a pad part, and tying members integral with said base and pad parts, said tying members connecting said base and said pad parts and extending through the smaller holes in said webs, said tying members defining support means integrally formed with the boss of said interconnecting means, said tying members and said smaller holes being arranged so that the bracket is moldable in place on said web from a single side of said web.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-12-10 | 1983-06-11 | 1983-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-10 | 1987-06-11 | 1987-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-10 | 1991-06-11 | 1991-12-11 | $7700.00 | Window Closed / Lapsed |