Land vehicles: bodies and tops – Tops – Load cover
Reexamination Certificate
2000-08-21
2002-06-11
Pape, Joseph D. (Department: 3612)
Land vehicles: bodies and tops
Tops
Load cover
C296S100060
Reexamination Certificate
active
06402224
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention generally relates to covers over the openings of large containers, such as transfer trailers. More specifically, the invention relates to a control mechanism for opening and closing such covers.
Many different types of large containers are used for hauling loads and waste, such as solid waste, construction debris, landscape materials, recyclables, etc. One such type are wheeled containers designed for hauling by trucks, known as “transfer trailers”. Transfer trailers are typically rectangular-shaped with open tops. Covers over the open tops are typically provided to prevent the load from spilling, sliding or being blown out the top of the container during transport. These covers have taken various forms in the past, including tarpaulin, lightweight nylon doors, open mesh plastic screens, etc. Some past trailer cover doors have consisted of two half-doors each rotating about a pivot point located adjacent each sidewall of the trailer. However, the doors may be 45 feet in length, and may each weigh 400 pounds, for example. Thus, the doors may be too heavy to manually open and close, and for this purpose hydraulic power mechanisms have been employed.
Known rotation control mechanisms for flip tops have disadvantages. They do not maintain control of the cover door(s) during their entire rotation. Thus, once a door has been rotated over-center, conventional powering mechanisms allow it to free fall down and possibly be damaged upon impact with the outer sidewall of the container. In the case of hazardous waste, for example, the doors need to be tightly sealed, such as by using a rubber gasket seal, and this may be impossible if the doors are sufficiently damaged, such as being bent. Further, such powering mechanisms have been relatively expensive since they have required relatively large hydraulic pressures to accomplish door rotation.
Accordingly, it is an object of the present invention to provide a control mechanism for a trailer cover which maintains control of the cover doors during their entire rotation, preventing damage to the doors and/or the trailer.
It is another object of the invention to provide a control mechanism for covering a container opening which requires relatively low hydraulic or air pressure as compared to conventional control mechanism, enabling the more economic manufacture and use of the trailer.
DEFINITION OF CLAIM TERMS
The following terms are used in the claims of the patent as filed and are intended to have their broadest meaning consistent with the requirements of law. Where alternative meanings are possible, the broadest meaning is intended. All words used in the claims are intended to be used in the normal, customary usage of grammar and the English language.
Container: Any large receptable, including but not limited to a transfer trailer, such as containers used for holding and/or hauling loads or waste.
Linkage mechanism: A system of links or bars which are joined together.
SUMMARY OF THE INVENTION
The objects mentioned above, as well as other objects, are solved by the present invention, and overcome disadvantages of prior art mechanisms for controlling the opening and closing of large container covers, such as transfer trailer doors, while providing new advantages not believed associated with such mechanisms.
In one preferred embodiment, a device is provided for controlling the opening and closing of at least one door covering at least part of an opening of a container, such as a transfer trailer or other container. The door(s) may be pivotally or otherwise attached to various locations on the container such as at an upper edge of the container, for example. The device includes one or more power mechanisms attached to the container for driving rotation of the door. The power mechanism may include a hydraulic cylinder or an air-powered cylinder, for example. At least one linkage mechanism is connected to the power mechanism, and transfers force from the power mechanism to open or close the door, such as by driving its rotation. Preferably, the door(s) remains under constant control, such as under constant rotational control, of the power mechanism during its opening and closing. Preferably, the door rotates through at least about 180° and, more preferably, rotates through at least about 270°.
In a preferred embodiment, at least one arm is provided which is slidably and pivotally connected to the at least one door and also pivotally connected to the container, and the linkage mechanism substantially increases the rotational mechanical advantage imparted by the power mechanism to the at least one arm. In a preferred embodiment, the linkage mechanism may include first and second links. The first link may be pivotally connected to the power mechanism and to a wall of the container, and the second link may be pivotally connected to the first link and to the arm. In one embodiment, one link may be curved and the other may be straight, allowing the use of links in the same or substantially the same plane. The curved link may be pivotally attached to the container, and the straight link may be pivotally attached to an intermediate portion of the arm and also pivotally attached to the curved link. In an alternative embodiment, two straight links may be used, in which case they may be designed to be in different or substantially different planes. In a particularly preferred embodiment, a first four-bar linkage connected to the power mechanism drives a second four-bar linkage connected to the door.
In a particularly preferred embodiment, the ratio of cylinder pressure (psi) to door weight (pounds), or the “cylinder pressure-to-door weight ratio” is preferably less than about 3.0, and more preferably less than about 2.0. Also with the present invention the ratio of cylinder force to door weight, or the “cylinder force-to-door weight ratio” is about 22, and in preferably in the range of about less than 30, and more preferably less than about 25. In a preferred embodiment, a power mechanism employs at least one hydraulic cylinder under pressure of less than about 2000 psi, and more preferably less than about 1000 psi.
REFERENCES:
patent: 1451127 (1923-04-01), Thornton
patent: 2408132 (1946-09-01), Weeks
patent: 3326595 (1967-06-01), Ogilvie
patent: 4627658 (1986-12-01), Vold et al.
patent: 4746257 (1988-05-01), Barry
patent: 4767152 (1988-08-01), Stluka et al.
patent: 4954039 (1990-09-01), Johnston et al.
patent: 5143496 (1992-09-01), Smith et al.
patent: 5388849 (1995-02-01), Arsenault et al.
patent: 5765986 (1998-06-01), Hulls
patent: 6041548 (2000-03-01), Miller
patent: 6120080 (2000-08-01), Hori et al.
Side Winder, taken from Enterprises Donovan Raise the Standard.
Schneider, R.T., Construction equipment: tough, easy to operate, and safe, taken fromHydraulics&Pneumatics, of Apr. 2000.
Standard Features Package, Impac.
Integrated Side Loader (ISL).
Wittke Waste Products, The Sprinter.
The Rand Challenger II.
The New Rand Champion.
Loadmaster, EnviroMaster.
Various ads for: Hydraulic Flip Tops for trailer beds, taken from The Hauler of Jun. 1999.
Sidewinder transfer trailer tarping system.
McClaim EZ Pak, prior door control system for transfer trailers (2 pages).
Duell Timothy L.
Gillum Christoph L.
Monaco Timothy A.
Galion Solid Waste Equipment Company Inc.
Morrow Jason
Niro Scavone Haller & Niro
Pape Joseph D.
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