Abstract:
The present invention concerns a seat suspension that includes a first section and a second section which are moveably connected. A deformable isolator is located between the sections. The isolator is held in place by a retaining means such a ring, post and in other ways. The isolator is comprised of a plurality of gaps separating solid sections which cooperate to resist the movement of at least one of the sections. This may be accomplished by resisting the movement of the section as it is urged against the isolator.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to seat suspensions. More specifically, the present invention relates to a seat suspension which uses an isolator to dampen movement in the suspension.  
         SUMMARY OF THE INVENTION  
         [0002]    In the construction of seat suspensions, for the comfort of the user, it is desirable to provide shock absorbers or dampeners which diminish or dampen forces transmitted to the seat. Such forces often include, but are not limited to, fore and aft movement and/or vertical movement.  
           [0003]    Typically, such dampeners are comprised of springs and various types of shock absorbers which may be gas charged or hydraulic. Typical examples of some of the different types of seat suspensions in which the present invention may be used are shown and described in U.S. Pat. Nos. 4,856,763 and 5,125,631, which are incorporated herein by reference.  
           [0004]    However, the use of such devices in a seat suspension increases the manufacturing cost of the suspension. Thus, there is a need to provide a dampening system which is comprised of inexpensive components. The present invention provides such a system through the use of components which are economical to obtain and/or manufacture.  
           [0005]    The present invention provides an isolator that functions as the dampener in the suspension. Movement in the suspension is transmitted to the isolator which causes the shape of the isolator to deform. As the isolator deforms, a resistance force is generated that acts against the force being applied.  
           [0006]    In another embodiment, the isolator includes a plurality of gaps. Resistance is created by compressing the gaps or colliding solid sections created by the gaps against other solid sections. In addition, the gaps may be larger near the center of the isolator. Configuring the isolator in this manner results in an ability to generate a resistance force that may exponentially increases in order to create a system that is capable of handling light forces as well as larger forces. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0007]    These and other features, objects and advantages of the present invention will become apparent from the following description and drawings wherein like reference numerals represent like elements in several views, and in which:  
         [0008]    [0008]FIG. 1 shows a typical seat suspension using one embodiment of the present invention.  
         [0009]    [0009]FIG. 2 is an exploded perspective view of one embodiment of the present invention with portions removed to reveal aspects of the present invention.  
         [0010]    [0010]FIG. 3 is a top view with portions removed to reveal aspects of one embodiment of the present invention.  
         [0011]    [0011]FIG. 4 is a partial cross-sectional view of the embodiment shown in FIG. 3 taken along line  4 - 4 .  
         [0012]    [0012]FIG. 5 is a fragmentary cross-sectional view of an embodiment of the present invention.  
         [0013]    [0013]FIG. 6 is a top view with portions removed to reveal aspects of an alternate embodiment of an isolator which may be used with the present invention.  
         [0014]    [0014]FIG. 7 shows another cross-sectional view illustrating an embodiment of the present invention.  
         [0015]    [0015]FIGS. 8 and 9 are top views of alternate embodiments of an isolator which may be used with the present invention.  
         [0016]    [0016]FIG. 10 is a graphical representation of the exponential resistance created by an isolator of the present invention.  
         [0017]    [0017]FIG. 11 is a partial perspective view illustrating another embodiment of the present invention.  
         [0018]    [0018]FIG. 12 is a partial perspective view illustrating another embodiment of the present invention.  
         [0019]    [0019]FIG. 13 is a partial perspective view illustrating another embodiment of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0020]    Set forth below is a description of what are currently believed to be the preferred embodiments or best examples of the invention claimed. Future and present alternatives and modifications to the preferred embodiments are contemplated. Any alternates or modifications in which insubstantial changes in function, in purpose, in structure or in result are intended to be covered by the claims of this patent.  
         [0021]    As shown in FIGS.  1 - 5 , one embodiment of the present invention includes a first section or plate  10  which includes an enclosure or housing  12 . Housing  12  retains isolator  20  which may be deformable. In the example described, housing  12  and isolator  20  are shown as being circular in shape but other shapes may be used as well.  
         [0022]    Located opposite plate  10  is a second plate or section  16 . Depending from a portion of plate  16  is an actuator or pin  18 . Actuator  18  is sized to fit within an aperture  22  located in isolator  20 . While actuator  18  is shown as cylindrical in shape, it may be of any shape and size that permits engagement with isolator  20  or allows the isolator to be in communication with both sections. As would be known to those of skill in the art, sections or plates  10  and  16  may be configured to operate in conjunction with additional assemblies found in typical seat suspensions including, but not limited to, seats, frames, scissor assemblies, guide assemblies and the like.  
         [0023]    In a preferred embodiment, opposingly located guides  30  and  32  slidingly connect plate  10  to plate  16 . This permits plate  16  to move relative to plate  10 , which may be stationary. Of course, other arrangements may also be used to permit section  10  to move relative to section  16 .  
         [0024]    As shown in FIGS. 3, 6,  8  and  9 , isolator  20  may be comprised of a plurality of raised lobes  40 - 47  which are solid sections formed by a plurality of spaces or gaps  50 ,  52  and  54 , among others. The gaps create at least one pathway  70  between the solid sections or masses. As shown, isolator  20  may be comprised of a number of different shapes. In addition, isolator  20  may even be a solid.  
         [0025]    As shown in FIGS. 3, 6,  8  and  9 , the spacing or gaps between the lobes or solid sections may be varied and in some instances greater in distance near the center. The lobes may also be all of the same configuration or different shapes as shown. In addition, the gaps may extend completely or partially through the isolator.  
         [0026]    In use, isolator  20  may be used as a shock absorber to dampen forces which may act upon the seat suspension. The invention may be used to dampen forces in any direction desired including, but not limited to, fore and aft, vertical, and/or sideways or in other directions. However, for ease of explanation, a description of how the present invention may be used to dampen fore and aft forces is provided.  
         [0027]    As a force is applied to the device, actuator or pin  18  is pressed against isolator  20  which may be made of a deformable material such as rubber which is one inch in thickness and four inches in outer diameter. Of course, other materials which deform when acted upon may be used as well.  
         [0028]    When actuator  18  presses against isolator  20 , the material is compressed or deformed and compresses the gaps and then may cause the solid portions to collide with one another. This creates a resistance force which works to push actuator  18  back towards its original position. Once the force acting upon actuator  18  is fully dampened, the elasticity of the isolator will return the seat suspension to its original operating position.  
         [0029]    The amount of resistance created by isolator  20  depends upon the mass and shape of the isolator, the size of the solid portions, as well as the size of the gaps. It has been found that the closer each of the solid portions are located to one another, the greater the resistance force generated.  
         [0030]    In another embodiment of the present invention, the size of the gaps varies to create different resistance curves. For example, as shown in FIG. 10, an exponential resistance is created by having the spacing be greater in the area near the center of the isolator. In this configuration, the initial movement of actuator  18  is met with a smaller amount of resistance which assists in smoothly dampening light loads placed on the suspension. However, as greater loads are applied to the system, actuator  18  will continue to deform isolator  20  causing the more closely spaced sections to collide or impact one another. This increases the resistance created. Isolator  20  will then absorb the force and return the suspension to its operating position. This embodiment of the present invention is capable of dampening all types of loads or forces encountered, with the resistance correspondingly increasing with the load applied.  
         [0031]    As shown in FIGS.  6 - 7 , in another embodiment, plate  16  and actuator  18  remain stationary while plate  10  is the moveable component. Again, guides  30  and  32  assist in allowing for ease of movement. In this embodiment, the operation of the device is reversed with isolator  20  being urged by housing  12  against actuator  18  by the forces that are applied to the suspension.  
         [0032]    As shown in FIGS. 11 and 12, isolator  20  need not be engaged in an aperture located in the center of the isolator. The aperture may be located in other areas as well. For example, FIG. 11 shows section  16  having pins or actuators  80  and  82  which are received by apertures  84  and  86  in isolator  20 . Section  10  may also include pins  90  and  92  which are received by apertures  94  and  96 . FIG. 12 shows that plate  10  may include pins  60 - 63  which are received by apertures  64 - 67 . In both of these configurations, enclosure  12  is not needed and may be eliminated since the pins extending from sections  10  and  16  will sufficiently retain isolator  20 . Moreover, isolator  20  may be engaged along other points as well including a side or sides, top, bottom and other locations.  
         [0033]    [0033]FIG. 13 shows an embodiment in which enclosure or housing  12  does not extend fully around isolator  20 . Instead pins  100 - 103  on plate  10  are received by apertures  104 - 106 . Isolator  20  is retained by plate  10  through an enclosure that consists of a plurality of segments  110 -  113  which engage the outer edge of isolator  20  at various points along the isolator.  
         [0034]    While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those of ordinary skill in the art that changes and other modifications can be made without departing from the invention in its broader aspects. Various features of the present invention are set forth in the following claims.