US3580404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Loading ramps for trailers
Assignee: Individual
•
Filing: 1969-07-31
•
Granted: 1971-05-25
•
Expires: 1989-07-31
Abstract
Abstract Ramp assemblies are disclosed mounted upon the rear of a lowboytype trailer for loading construction equipment. Each assembly is of two hingedly attached sections collapsible to a raised, stowed positions by an arm engageable with both of the sections to lift same and to maintain same in a stowed position. A hydraulic circuit is included for selective control of each ramp assembly.
Inventors
- 👤 William J Moser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:27
CPC Classifications
B; B60; B60P; B60P1/00; B60P1/43
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
195 words
In combination with a heavy equipment carrying trailer, a pair of ramp assemblies for loading and unloading such equipment with each ramp assembly comprising: a main ramp section and an outer ramp section hingedly linked at their common ends and the main ramp section swingably mounted at its other end to the rear of the trailer, a ramp operating means including an arm unit subjacently disposed to the ramps for vertical movement by a hydraulic cylinder for raising and for lowering of the ramp sections, and said arm unit comprising an elongate arm having a first pair of components intermediate the ends of the arm contactable with the main ramp section and a second pair of components carried at the outer end of said arm and also contactable with the main ramp section to advantageously impart initial lifting movement to the main ramp whereupon subsequent to the initial lifting movement of the main ramp section said first pair of components will complete the lifting thereof while said second components will contact the outer ramp section to retain same in spaced relationship to the main ramp section for ramp assembly stowing during transport of the trailer.
Claim 2
Dependent Claim
195 words
In combination with a heavy equipment carrying trailer, a pair of ramp assemblies for loading and unloading such equipment with each ramp assembly comprising: a main ramp section and an outer ramp section hingedly linked at their common ends and the main ramp section swingably mounted at its other end to the rear of the trailer, a ramp operating means including an arm unit subjacently disposed to the ramps for vertical movement by a hydraulic cylinder for raising and for lowering of the ramp sections, and said arm unit comprising an elongate arm having a first pair of components intermediate the ends of the arm contactable with the main ramp section and a second pair of components carried at the outer end of said arm and also contactable with the main ramp section to advantageously impart initial lifting movement to the main ramp whereupon subsequent to the initial lifting movement of the main ramp section said first pair of components will complete the lifting thereof while said second components will contact the outer ramp section to retain same in spaced relationship to the main ramp section for ramp assembly stowing during transport of the trailer.
Claim 3
Dependent Claim
27 words
The invention as claimed in claim 1 wherein said first and second pairs of components are rollers for rolling engagement with the underside of the ramp sections.
Claim 4
Dependent Claim
49 words
The invention as claimed in claim 1 wherein the hydraulic cylinder of each ramp operating means is in a hydraulic circuit including separate valve controls for each of said cylinders for individual operation of each ramp assembly, independently operable to raise and lower their associated ramp sections in sequence.
Claim 5
Dependent Claim
53 words
The invention as claimed in claim 1 wherein said elongate arm is of a length to locate said second pair of components adjacent the outermost end of the main ramp section when the latter is operatively disposed in a lowered position whereby efficient leverage is achieved during initial movement of the ramp sections.
Claim 6
Dependent Claim
50 words
The invention as claimed in claim 1 wherein a mechanical lock comprising an elongate member attached at one of its ends to he trailer chassis and is adapted for engagement at its opposite end with the ramp sections of a ramp assembly to retain same in a raised stowed position.
References Cited (Backward Citations)
US3142394A
Cited
US3516560A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |