US4174021A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ladder truck
Assignee: ALNOR MATERIAL HANDLING Ltd
•
Filing: 1978-05-16
•
Granted: 1979-11-13
•
Expires: 1998-05-16
Abstract
Abstract A ladder truck, e.g. for use in stores for transporting goods from central storage to display shelves and for facilitating the loading of such goods on display shelves, comprises a wheeled truck having attached to one end a stepladder. The stepladder is pivotally secured to one end, and has a first position in which it is wholly supported by the truck, clear of the ground, so that the truck can be wheeled around without interference from the stepladder and a second position in which the lowermost extremities of the stepladder engage the ground or floor surface, and take a portion of the weight of the truck, so that the adjacent wheels of the truck are raised clear of the supporting ground surface. Then, with the truck resting on a single wheel or pair of wheels and on the base of the stepladder, the truck is effectively locked against accidental rolling movement across the surface, and the stepladder can be safely mounted. The stepladder is easily moved from one position to another by simple manual operation.
Inventors
- 👤 Norman A. Barlock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:49
CPC Classifications
E; E06; E06C; E06C5/00; E06C5/02; B; B62; B62B; B62B5/00; E06C1/00; E06C1/02; E06C1/38; E06C1/397
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
328 words
A ladder truck comprising: a truck portion having first and second supporting wheel formations near opposed ends thereof, on which the ladder truck may be rolled across a surface; a step ladder movably secured to the truck portion at the first end thereof and having a single pair of downwardly extending surface engaging extremities; a pair of pivot arms pivotally connected at one end to the upper part of the first end of the truck portion and pivotally connected at the other end to an upper portion of the step ladder; said step ladder being movable relative to the truck portion by pivoting movement of said pivot arms in a vertical plane relative to both the truck portion and the step ladder, between: a first position in which the step ladder is supported by the truck portion with its downwardly extending extremities clear of the surface on which said wheel formations rest, so as to permit the ladder truck to be rolled across the surface on its wheeled formations, the pivot arms in said first position extending from their connection to the end of the truck portion to their connection to the step ladder in a direction upwardly and rearwardly towards the centre of the truck portion; an intermediate portion in which the pair of downwardly-extending extremities of the step ladder, and each of the supporting wheel formations, rest on said surface, the pivot arms in said intermediate position extending outwardly in a direction away from the truck portion; and a second position in which the downwardly-extending extremeties of the step ladder engage the surface and support a portion of the weight of the ladder truck thereon, with the first said supporting wheel formations raised out of engagement with the surface, the pivot arms in said second position extending from their connection to the end of the truck portion to their connection to the step ladder in a direction downwardly and rearwardly towards the centre of the truck.
Claim 2
Dependent Claim
328 words
A ladder truck comprising: a truck portion having first and second supporting wheel formations near opposed ends thereof, on which the ladder truck may be rolled across a surface; a step ladder movably secured to the truck portion at the first end thereof and having a single pair of downwardly extending surface engaging extremities; a pair of pivot arms pivotally connected at one end to the upper part of the first end of the truck portion and pivotally connected at the other end to an upper portion of the step ladder; said step ladder being movable relative to the truck portion by pivoting movement of said pivot arms in a vertical plane relative to both the truck portion and the step ladder, between: a first position in which the step ladder is supported by the truck portion with its downwardly extending extremities clear of the surface on which said wheel formations rest, so as to permit the ladder truck to be rolled across the surface on its wheeled formations, the pivot arms in said first position extending from their connection to the end of the truck portion to their connection to the step ladder in a direction upwardly and rearwardly towards the centre of the truck portion; an intermediate portion in which the pair of downwardly-extending extremities of the step ladder, and each of the supporting wheel formations, rest on said surface, the pivot arms in said intermediate position extending outwardly in a direction away from the truck portion; and a second position in which the downwardly-extending extremeties of the step ladder engage the surface and support a portion of the weight of the ladder truck thereon, with the first said supporting wheel formations raised out of engagement with the surface, the pivot arms in said second position extending from their connection to the end of the truck portion to their connection to the step ladder in a direction downwardly and rearwardly towards the centre of the truck.
Claim 3
Dependent Claim
49 words
The ladder truck of claim 1 wherein the truck portion thereof has stop formations at the ladder attaching end thereof, against which the step ladder rests when in said first position, the step ladder in said first position being angularly disposed to lean its weight against said stop formations.
Claim 4
Dependent Claim
56 words
The ladder truck of claim 2 including a further pivotal and sliding connection between the step ladder and the truck portion at a lower location thereof, said pivotal and sliding connection comprising link arms pivotally connected to the step ladder and slidably connected to the end of the truck portion for relative vertical sliding movement thereon.
Claim 5
Dependent Claim
67 words
The ladder truck of the claim 3 including lower stop means on the end of the truck for engagement with said link arms so as to define their lower most sliding position relative to the end of the truck, and to define the separation of the lowermost extremity of the step ladder from the end of the truck when the stepladder in in its second said position.
Claim 6
Dependent Claim
54 words
The ladder truck of claim 4 wherein the step ladder includes a plurality of shelf-like rungs, each of said rungs being disposed in a substantially horizontal position when the step ladder is in its second, mounting position, and in a non-horizontal position when the step ladder is in its first and its intermediate positions.
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) | 1982-11-12 | 1983-05-14 | 1983-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-12 | 1987-05-14 | 1987-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-12 | 1991-05-14 | 1991-11-13 | $7700.00 | Window Closed / Lapsed |