Patent Application
20130062841
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1. Field of the Invention
This present invention relates to off-road vehicles, including vehicles for use on un-improved or poor quality road surfaces.
2. Description of the Prior Art
There is currently much concern for agricultural productivity, given the expanding world population. This is further exacerbated by the practice of using feed grain crops for making motor vehicle fuel. It is paramount that we make the best possible use of agricultural resources. One way to do this is to greatly expand irrigation by distributing water on a continental basis. This enlargement of agricultural operations could lead to a need for far more agricultural workers. Hopefully, we can find a way to do this within a legal immigration framework. A good start could be based on a new kind of apparatus that would enhance productivity of workers and make the work into a more attractive activity.
Some kinds of agricultural work are hard, slow, and uncomfortable. It is difficult to find workers and pay them enough to get them to do such tasks. To improve this situation with a machine requires both better productivity and greater comfort of the worker. Productivity has to be better per worker in order to make the cost of the machine affordable. Worker comfort has to be provided to attract worker, but also to enable more effective and sustained performance of tasks. Cost of the machine has to be compatible with expectations for improved productivity. Perhaps of greatest importance is the need for energy efficient operation. The intent is that the wages payable would ultimately increase. Still more fundamental are requirements for worker safety.
Compared with most generally familiar vehicles, agricultural vehicles of the sort that would significantly assist farm workers have significantly different performance requirements, and some of these offer potential for unique new system solutions. The biggest of these is the fact that for manual work, unusually low speed is desirable. Another key difference is that the low seat that would enable workers to reach to the ground would mean that conventional notions of how to stabilize a vehicle are inapplicable; particularly, a wide wheel base is not needed. Furthermore, the low operator riding position means that stability need not be so absolute since a roll over event would not be particularly hazardous; as we would normally think of such events for farm tractors. A design freedom is the fact that the overall length of a vehicle oriented toward row crop work can be quite large, enabling a vehicle and various ancillary equipment configured in a narrow but long train.
We look at the historical background for apparatus of this sort in the vast field of agricultural vehicles. Very little is found in the way of simple machines to enable hand work in the fields. Rather, the tendency seems to be to develop tractor based solutions or tractor like systems. Tractors make it possible for some kinds of crops to automate the work and to provide very comfortable cab conditions. For some types of crops this leads to very successful operations utilizing ever larger tractors and harvesters of many types. However, the present need seems to call for different approaches. In many situations, the needed work can simply can not be done from a large vehicle because of the need for hand work close to the ground or for workers to be in positions relative to growing crops that would be awkward from large vehicles. Large vehicles are often not desirable because the crops themselves interfere with access by such vehicles, and unfortunately, this can lead to farming methods where crop spacing does not make the best possible use of land resources, simply because land must be reserved to allow for the vehicle to pass.
U.S. Pat. No. 3,589,744 Hansen 1971 illustrates an apparatus intended to function as an aid to workers. This seems well suited for row crop work.
Less satisfactory is a situation where the vehicle prevents crop spacing that would make the best use of land resources is shown in U.S. Pat. No. 3,546,856 Hiyama 1970, FIG. 2. Somewhat better, but still intrusive is the apparatus of U.S. Pat. No. 4,250,700 Horn et al. 1981. A farming system where it is desirable to enable both the worker and vehicle to pass under growing crop vines as illustrated by the U.S. Pat. No. 3,546,856 Hiyama 1970, FIG. 1 and U.S. Pat. No. 5,423,166 Scott 1995, thus showing the disadvantages of vehicles of the size range usually found in farm vehicles. Further, U.S. Pat. No. 5,423,166 Scott 1995 illustrates the intrusiveness of both grape acquisition machinery and the associated trailer by which harvested grapes are collected.
Many vehicle configurations have been invented with these purposes in mind. Many tend to be constrained to conventional ways of thinking about tractors, farm vehicles that already exist, and about automobiles. Though the invention U.S. Pat. No. 3,589,744 Hansen 1971 seems to be useful, it is complicated. Conventional wheels with balloon type tires mounted are arranged in a three point stabilizing form, generally like many farm tractors, but also harking back to the three wheeled Morgan roadster of long ago. This is adapted to working on low growing crops with over-arching structure that allows passing over crop rows, but all this leads to complicated equipment, when simplicity is needed to allow inexpensive construction. Still this invention by Hansen is successful in providing a low seat for a worker that enables low crop access, all the way to ground level. Hansen shows one wheel that is relatively large which would help hold down drag when traversing over soft earth, but this of course does not indicate an attempt to use this for stability. Reduced width and low seating is shown in U.S. Pat. No. 2,583,358 Cesan 1952, though this offers only a partially effective capability to operate in soft dirt, and width is wider than desired for efficient operation.
Continuous track vehicles serve to enable operation on soft dirt. A wide variation of such a track would offer lateral stability to prevent roll over, should it be used for that purpose, and the included wheels with the track could provide a wide wheel base if needed. The wide range of use of tracked vehicles in agriculture is represented by U.S. Pat. No. 1,376,649 Schneider 1921 and U.S. Pat. No. 4,683,969 Littau 1987. U.S. Pat. No. 7,543,664 Nelson 2009 shows a rubber version, and though this is not indicated, this could be adapted to provide stability as well as load spreading benefits. Generally, vehicles using tracked wheel systems arrange for the tracks to act in widely spaced pairs to provide stability. Rubber forms of tracked systems are used in snow-mobiles, where the track acts to provide stabilization.
Comparing again to U.S. Pat. No. 3,589,744 Hansen 1971, a simpler vehicle would be the recumbent bicycle as illustrated with a sidecar in U.S. Pat. No. 6,565,106 Lopez 2003. With or without a motor or engine this at least shows the basic simplicity needed. A tricycle form of this recumbent bicycle is an obvious variation that can be occasionally seen in use, but this would be still quite useless for the present purpose given that these wheels, though large in diameter, are narrow such that they would sink in soft dirt and cause much resistance to vehicle movement. The obvious tricycle form often includes wide, laterally spaced wheel sets; significantly wider than what would be desired for carrying a worker between narrowly spaced rows.
A very simple aid to workers would be the wheeled stool of U.S. Pat. No. 3,614,120 Cicero 1971 where a seat is provided with a seat back at a slanted position that would make low work more comfortable. This invention shows wide wheels but these are shown as they are mostly for convenience, as they are indicated to be typical rubber balloon tires. Stability for this “Chair Cycle” depends on the use of the legs and feet of the worker, not a lot differently from the way one legged milk stools were stabilized by the user.
One impediment to progress is the widely used rubber, balloon, tractor tire such as indicated in U.S. Pat. No. 3,589,744 Hansen 1971. This works fine where there is a pair of widely spaced wheels that achieves stability, but by itself offers no resistance to rolling sidewise. But wide spacing is exactly what we are not looking for, in order to accomplish the present purposes for enabling more effective crop work.
Curiously, tractor tires of the 1920s utilized hard steel wheels with large spikes bolted to them, where these spikes were called lugs. Because the typical farmer used regular roadways to get tractors from field to field, these lugs caused much disruption of smooth road surfaces. All this went away with inflated rubber tires of the mentioned balloon type. Lugs might not matter to stability, and they could be advantageous in a low speed vehicle.
Searching for solid wheels that would improve stability with a narrow wheelbase turned up U.S. Pat. No. 1,210,056 Fairman 1916 where a narrow vehicle is fitted with hard wheels. This vehicle is questionable as to safety given the high seat position, and of course this configuration does not suggest any interest in enabling hand work on low crops. A tractor utilizing hard wheels configured of lateral slats overlaid with slanted gripping ridges is shown in U.S. Pat. No. 2,560,384 Crain 1951. Though far from the field of farm vehicles, a relevant solid drum wheel is shown in the baby carriage for use in soft dirt of U.S. Pat. No. 5,158,319 Norcia et al. 1992, though there is no low seat for farm work and no special stabilizing purpose involved other than that of conventional baby carriage wheels.
U.S. Pat. No. 6,752,228 Aoyama 2004 reminds us of a function of agricultural vehicles depending on existence of tow bar capabilities, but it also illustrates the difficulty that is encountered in making the seat position truly low. This particular invention is announced as one that enables a low profile operation.
Extracting fragments and general ideas from past machine practice led to invention of a simple farm vehicle to support manual work. It would be particularly useful for work on low growing crops. A low seating position is provided for a worker and the lateral dimension is small to enable fitting through narrow spaces such as narrowly spaced crop rows, but elongated to enable needed functions.
The vehicle includes a frame with an attached wheel set and an attached seat for a worker that enables the worker to ride facing generally in the forward direction of travel. The entire vehicle is approximately the width of that seated worker. Within such narrow width confines, the wheel set is configured for both stability and efficiency in dirt.
Adequate stabilization generally excludes the use of wide balloon tires, such as commonly used as the rear tractor tires, having a rounded profile of the tire casing, since these offer little stability beyond slight stiffness of their sidewalls. Instead, wheels systems that have hard outer edges are utilized here, such that a relatively flat lateral surface makes contact with the soft ground.
Energy efficiency for a wheel rolling in dirt comes from minimized pressure on the ground due to a large contact surface achieved with lateral width and maximum practical diameter. Thus there is minimal required traction force, even where some significant load is carried.
Benefits are significant. The very low seat height, that just enables ground clearance, means that the requirement for stability is somewhat lessened, since a roll over event would not be particularly serious; this being the case given that falling would be from that very low position. Unlike with most vehicles, low speed operation greatly reduces hazards of vehicle operation, and absolute stability is not vital.
A myriad of uses would require ancillary equipment of an extent like that available for use with farm tractors and specialty harvesting machines now. These are represented by the prior art discussed here, and the suggestions garnered from these, as well as the implementation details offered there, are incorporated by reference into the present disclosure. Low growing row crops, vineyards, orchards are examples of the range of crop types anticipated, where a much less obtrusive vehicle can be used to advantage. Completely new harvester systems are indicated.
The simplest embodiment of this invention is first described, but as many applications of farm tractors are considered, the variations in form and ancillary equipment evolve significantly. All such applications would be expansions on the basic invented concept. Other applications hitherto not related to operation of farm tractors also have emerged, and others are expected. The intention here is to show the scope of the invention by mention of variations and adaptations.
The invention here was done based on generally known apparatus most of which was known prior to reference to the patent literature described in the background section previously included here. However, the background art clearly shows limited extension of industrial technology to the agricultural world to provide what could be important changes in agricultural practice. Thus that practice carries on inadequately, seemingly unaware that industrial approaches could minimize the difficulty and discomfort of the work, not to mention what such approaches could do to enhance productivity of both workers and land.
The rear wheel assembly of the wheel set 3 is here implemented as a single drum for purposes of achieving ultimate simplicity and enabling low cost construction. Because of the fundamentally narrow form, the skidding that otherwise necessitates a differential to enable differing rate of rear wheels in turns, is much reduced. A combination of steel and plywood is anticipated to provide durability of steel as needed but light weight of plywood when it is sufficient for the purpose intended.
In
And of course such drums are not limited to running on an earth surface, so this represents an adaptation for whatever uses might be desired for an apparatus according to this invention. The large diameter, wide wheel offers a larger footprint area which minimizes sinking into any soft surface. A snowmobile application is a good example.
Further invention disclosures are planned which would cover variations of the basic concept here disclosed, as well as various related types of special harvesting equipment and other farm operation aids. Suggestions are available from the prior art discussed in the background of this present document.
The scope of the invention is to be defined by the appended claims.
