US3625534A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lift linkage for a low-lift truck
Assignee: AC MATERIAL HANDLING Corp 777 MANOR PARK DRIVE COLUMBUS OHIO 43228 A CORP OHIO
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Filing: 1970-06-10
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Granted: 1971-12-07
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Expires: 1990-06-10
Abstract
Abstract The elevating platform of a low-lift-type lift truck is connected to the frame of the truck through a pair of parallel links which are spaced vertically and longitudinally from one another. The lower pair of links are disposed below a battery support and the upper pair of links are disposed forwardly of the battery. A single upstanding hydraulic jack is employed to raise and lower the load carrying platform through a connection with the lower pair of links.
Inventors
- 👤 William J Harrison
- 👤 Dennis G Harvey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:15
CPC Classifications
B; B62; B62B; B62B3/00; B62B3/04; B62B3/06; B62B3/0618
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
243 words
In a lift truck a main frame, including a battery support portion, a steering head pivotally connected to said main frame in front of said battery support portion for steering movement on a vertical axis and including a support wheel and a control handle, an elevating platform having an upstanding structure at its front end, forwardly of said battery support portion, wheel-supporting arms pivotally connected to the rear end of said platform, wheels on said arms, connecting means securing the front end of said platform to said main frame including a first pair of links pivotally connecting the upper end of said upstanding structure to said main frame, forwardly of said battery support portion, and a linkage assembly having a second pair of links disposed below said battery support portion and pivotally connecting said main frame and said elevating platform, said second pair of links being spaced below and parallel to said first pair of links and a member rigidly interconnecting said second pair of links, a pair of longitudinally extending rods on the lower side of said platform pivotally connected at their front ends to said second pair of links, respectively, and pivotally connected at their rear ends of said rods to said arms, respectively, and an upstanding hydraulic jack having its upper end pivotally connected to said frame and its lower end pivotally connected to said assembly, said elevating platform being raised relative to said frame upon expansion of said jack.
Claim 2
Dependent Claim
243 words
In a lift truck a main frame, including a battery support portion, a steering head pivotally connected to said main frame in front of said battery support portion for steering movement on a vertical axis and including a support wheel and a control handle, an elevating platform having an upstanding structure at its front end, forwardly of said battery support portion, wheel-supporting arms pivotally connected to the rear end of said platform, wheels on said arms, connecting means securing the front end of said platform to said main frame including a first pair of links pivotally connecting the upper end of said upstanding structure to said main frame, forwardly of said battery support portion, and a linkage assembly having a second pair of links disposed below said battery support portion and pivotally connecting said main frame and said elevating platform, said second pair of links being spaced below and parallel to said first pair of links and a member rigidly interconnecting said second pair of links, a pair of longitudinally extending rods on the lower side of said platform pivotally connected at their front ends to said second pair of links, respectively, and pivotally connected at their rear ends of said rods to said arms, respectively, and an upstanding hydraulic jack having its upper end pivotally connected to said frame and its lower end pivotally connected to said assembly, said elevating platform being raised relative to said frame upon expansion of said jack.
Claim 3
Dependent Claim
29 words
The invention of claim 1 wherein one of said second pair of links has a forward extension and said lower end of said jack is connected to said extension.
Claim 4
Dependent Claim
110 words
The invention of claim 1 wherein said first pair of links are pivotally connected to said main frame on a first transverse axis and extend rearwardly therefrom, said second pair of links are pivotally connected to said frame on a second transverse axis spaced rearwardly and below said first axis and extend rearwardly therefrom, said first pair of links are pivotally connected to said upstanding structure on a third transverse axis and said second pair of links are pivotally connected to said elevating platform on a fourth transverse axis, said first and second pairs of links and their pivot connections with said frame and elevating platform establishing a parallel linkage.
Claim 5
Dependent Claim
44 words
The invention of claim 3 wherein said vertical axis is in the longitudinal vertical plane of the truck, said jack is disposed to one transverse side of said plane and has its lower end connected to a forwardly extending portion of said linkage assembly.
Claim 6
Dependent Claim
35 words
The invention of claim 4 including a tension spring connected at one end to one of said links and at its other end to said frame whereby said platform is biased toward its lowered position.
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) | 1974-12-06 | 1975-06-07 | 1975-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-06 | 1979-06-07 | 1979-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-06 | 1983-06-07 | 1983-12-07 | $7700.00 | Window Closed / Lapsed |