Abstract:
An apparatus and method for creating and utilizing a low friction structure is provided. The low friction apparatus (LFA) of the present embodiments allow for moving a load across a work surface with minimal effort. The LFA provides for easier movement over a transport surface area, wherein the impact of a large bearing area is minimized using minimal friction. The LFA is further adapted to greatly reduce the frictional force between a load and a work surface thereby allowing low surface stress on a work surface combined with ease of movement. In addition, the LFA provides low friction and subsequent ease of motion even while turning or moving sideways since its characteristics are non directional.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to materials handling in general and, in particular, to a low friction structure for easier movement over a transport surface area. 
       BACKGROUND 
       [0002]    Frozen water is known for its low friction properties. Most often, frozen water (e.g., snow) constitutes the low friction transport surface on a mountain side. At other times, the same frozen water in the form of ice constitutes the low friction transport surface in a skating setting. The low friction aspect of ice becomes the basis for skiing, sledding and many other winter sports. Ice has a high compressive strength but is generally not structurally stable by itself because it has a low tensile strength (about 1/10 the compressive strength). Ice melts over 32° F. and yields continually under strain. Glaciers vividly demonstrate this. 
       SUMMARY 
       [0003]    It would be desirable to capture the low friction aspect of ice without it being necessary to have the environment covered with ice or snow. Consequently, it would be possible to move objects, particularly heavy objects, without the normal frictional forces opposing such movement. 
         [0004]    One embodiment provides a method for easier movement over a transport surface area, wherein the surface stress is lowered, comprising: placing strategically a plurality of structures under the load thereby allowing the load to be moved with minimal effort; and moving said load across a surface area wherein resistance to movement is minimized and induced stress is lowered across the transport surface area. 
         [0005]    Yet another embodiment provides an apparatus adapted to greatly reduce the frictional force between a load and a work surface thereby allowing low surface stress on a work surface combined with ease of movement, comprising: a support base that engages the load; and a chamber housing a low friction material coupled to the support base thereby inducing low stress on the work surface. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The teachings of the present embodiments can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which: 
           [0007]      FIG. 1  illustratively depicts a Low Friction Apparatus (LFA) according to one embodiment; 
           [0008]      FIG. 2  graphically depicts a cutaway view of Low Friction Apparatus (LFA) surface configuration according to one embodiment; 
           [0009]      FIG. 3  illustratively depicts a general Low Friction Apparatus (LFA)captive work surface configuration according to one embodiment; 
           [0010]      FIG. 4  illustratively depicts an alternate support base configuration according to one embodiment; and 
           [0011]      FIG. 5  illustratively depicts an alternate support base configuration according to one embodiment. 
       
    
    
       [0012]    To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. 
       DETAILED DESCRIPTION 
       [0013]    The present embodiments are primarily described within the context of a Low Friction Apparatus (LFA) and a method for easier movement over a transport surface area, wherein resistance to movement is minimized using minimal friction. However, those skilled in the art and informed by the teachings herein will realize that the invention is also applicable to other technical areas and/or embodiments. 
         [0014]      FIG. 1  illustratively depicts a general Low friction Apparatus (LFA) disclosed herein. Specifically, Low friction Apparatus (LFA)  100  comprises Ice Pod Chamber (IPC)  120 , a support base  130 . Ice Pod Chamber (IPC)  120  is generally circular since this allows non-directional characteristics for any direction of motion. 
         [0015]    In another embodiment, a shoe (rectangular) shape in the ‘track’ or captive work surface version as shown in  FIG. 3  is used. This would be primarily because the LFA would only move in one direction relative to the captive surface or ‘track’ configuration. IPC  120  is a structure that houses a low friction material. 
         [0016]    The embodiments described herein may selectively replace glides as a material conveyance and handling, but also wheels and bearings in certain applications. For example, using a small handlift truck for comparative purposes, wherein one of the wheels might have a solid rubber tread  8  inches in diameter with a 1¾ inch width tread. We may reasonably conclude that the contact patch at the base of the wheel under a 100 pound load is on order of 1 inch squared. The stress under the contact patch area is therefore, at least 100 pounds/1 in squared=100 psi. The term ‘at least’ is used because no tread pattern was assumed. If there were a tread pattern, the reduced contact area to form the tread pattern would have to be accounted for. 
         [0017]    An 8 inch diameter IPC (same size as the previous example wheel) would have a contact area of πD 2 /4 (area of a circle) equal to about 50 inches squared (in 2 ). The resultant stress under the same 100 pound load is therefore, 100 pounds/50 inches squared=2 psi. The possible benefits of reducing the contact area stress from 100 psi to 2 psi can immediately be seen. The IPC can be sized to keep surface stress safely below the yield stress of the working surface, in this case as low as 2 psi. If the same basic wheel design were kept but ‘sized up’ to reduce the design stress under a 100 pound load from 100 psi to 2 psi (keeping all dimensions in the same proportion) the resultant wheel would require a contact patch of 50 inches squared (since the original contact patch was I inch squared). The contact patch is two dimensional so we take the square root of 50 to find the multiplier. Taking the square root of 50 yields ˜7. Thus the dimensions of the wheel are multiplied by a factor of 7. The tread width would thus be 7×1¾=12.25 inches and the diameter would be 8×7=56 inches. A handlift truck with such oversized wheels (56 in.×12.25 in.) would be extremely cumbersome and of little utility. In addition, the IPC provides low friction and subsequent ease of motion even while turning or moving sideways since its characteristics are non directional. The wheel, conversely, provides ease of motion in only one direction, generates large stresses when moved sideways and increases surface stresses when turning. Thus, the present embodiments not only allow low frictional ease of movement, but also allow control of the surface handling stresses and therefore, eliminate elaborate material handling provisions in certain intermittent material handling situations or places where wheeled conveyance devices, tracked or untracked bearings, overhead hoists etc. are limited in space access or other physical constraint. 
         [0018]      FIG. 2  graphically depicts a cutaway view of Low Friction Apparatus (LFA) surface configuration. In one embodiment, low friction material  210  is ice. In other embodiment, other solid lubricant forms may be employed. Lubricants such as hard soap and hard wax block may be used. The deciding factor in determining the type of lubricants to use is that the coefficient of sliding friction multiplied by the load [(coefficient of sliding friction)×(load)] be lower than mechanical grip  250 . 
         [0019]    Mechanical grip  250 , which is a cushioning material or buffer prevents sliding of support base  130  relative to the low friction material. In one embodiment, mechanical grip  250  is a coarse woven material with random thread pattern providing enough mechanical grip. In another embodiment, the material is fiber cross-hair attached to the cushion. This fiber matrix tends to keep the low friction material moving in the desired direction of motion rather than allowing the support base to push on chamber walls  230 . In other embodiment, for heavy load applications carbide chips may be suitable. The function of the chamber wall is primarily to contain the low friction material within the perimeter of the chamber so that the low friction material can direct the force from the support base to the work surface or transport surface area. Ideally, there should be no lateral force transmitted from the support base to the chamber wall. 
         [0020]    Chamber wall  230  is made of material such as polyvinylchloride (PVC) plastic pipe in one embodiment. The material is chosen to both absorb any lateral pressure and provide an environment conducive to preserving the low friction material. In another embodiment, the material is made of steel or other hardened structure. In yet another embodiment, chamber wall  230  may be made of composite material. In a further embodiment, chamber wall  230  may contain filler material, which is used to achieve a specific quality. 
         [0021]    Generally speaking, any material capable of housing the low friction material may implement the various embodiments described herein. While PVC is generally discussed within the context of the description, the use of any other structural material is considered to be within the scope of the present embodiments. 
         [0022]    Support base  130  adheres to cushion  220 , which terminates with irregularly shaped mechanical grip  250 . Consequently, the interface of the support base and the low friction material is such that the support base is not free to slide on top of the low friction material, but grips the low friction material mechanically with sufficient surface porosity, mechanical projections or ‘tread’ pattern. Ice pod Chamber works best when grip of support base on the low friction material is greater than the friction of low friction material on the work surface. Support base  130  must be of sufficient thickness for the load. 
         [0023]    Ice Pod Chamber  120  further comprises at least two (2) devices in order to minimize contaminants from penetrating in the chamber. In one embodiment, these devices are flanges  240  terminated with brush bristles  260 . In other embodiment, these devices comprise an apparatus capable of effectively blocking a greater portion of contaminants from penetrating the chamber. 
         [0024]    Distance  140  is desirable with proper grip; sliding of the support base is to be minimized. Support base  130  will slide without proper grip. This result is unwanted because it would cause the support base to push on the chamber wall and increase friction at the interface of the work surface. 
         [0025]      FIG. 3  illustratively depicts a general Low Friction Apparatus (LFA) captive work surface configuration. Surface  310  is a captive work surface. In one embodiment, this surface is a skating setting. In another embodiment, the surface area is a skiing slope. Yet, in another embodiment, the surface is a specially constructed surface. 
         [0026]      FIG. 4  illustratively depicts an alternate support base configuration. Support base  410  is constructed such that it can be guided externally. In another embodiment, the support base is constructed such that it can be both externally and internally guided.  FIG. 5  depicts such embodiment. 
         [0027]    While the foregoing is directed to various embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. Thus, the invention should not be limited to use solely in any specific application identified and/or implied by such illustration. As such, the appropriate scope of the invention is to be determined according to the claims, which follow.