Abstract:
A vertically adjustable pedestal for a boat accessory such as a table or seat is made up of a pair of telescoped tubular members having opposite facing lengthwise recesses which contain rods to allow one member to adjustably slide with respect to the other yet preventing rotation. A releasable locking device holds the adjusted member at its desired elevation.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention is directed toward providing an adjustable pedestal for a boat accessory such as a table or seat by a pair of rigid tubular members which are vertically slidably telescoped with one end of one of the members adaptable for resting on a support surface, such as the deck of a boat, and the other end of the other member adaptable for attachment to the underside of a table or boat seat so that the latter can be placed at a desired elevation and then releasably locked in place.  
         DESCRIPTION OF THE PRIOR ART  
         [0002]    U.S. Pat. No. 5,385,323 in addition to describing earlier adjustable support devices or pedestals in which the support members are telescoped and which provide for the adjustment of the elevation of the attached device, describes a prior art device in which the inner telescoped tubular member has a series of spaced-apart grooves running parallel to its axis on its outer surface and the outer telescoped member having spaced-apart axially extending ribs on its inner surface for engaging respective grooves on the inner tubular member for use in supporting a boat seat. As mentioned in the &#39;323 patent the grooves and ribs are dimensioned so that they loosely fit together, when the two members are not frictionally locked together. This serves the purpose of allowing the members to be slidably adjusted with respect to one another while preventing them from rotating and allows sufficient space between the members so that foreign material will not likely adhere to the members in the inner spaces to interfere with the adjustability. While this has worked well with satisfactory results, there is a drawback. When the seat elevation is being changed, there is a wobbly feel to it so that the user, such as the boat owner, might consider this to be an inferior or not well-made product. In order to eliminate this problem, some table and seat pedestals have been made with telescoped tubular members with precision machined mating grooves and ribs so that they have a snug feel yet are slidably adjustable within one another. This of course adds considerable cost to the device and makes it subject to deterioration due to the elevation of the boat seat or table being repeatedly changed.  
         SUMMARY OF THE INVENTION  
         [0003]    A pedestal for supporting a boat table or boat seat and providing an adjustable elevation for the seat or table is formed with a pair of telescoped tubular members. The inner rigid tubular member has a series of identically dimensioned grooves or slots which are spaced apart from one another on its outer surface and the outer member has a corresponding and identical set of matching lengthwise grooves or slots which are spaced apart along its inner surface. One of the members is adapted for attaching to the underside of a boat seat or boat table and the other member at its opposite end is adaptable for attachment to a supporting surface such as a boat deck. A set of elongated bearing rods dimensioned to fit snugly in the slots or grooves of the members are placed to rest in the opposite facing grooves of both members. The rods may be removable, if necessary. The rods in the grooves prevent the members from rotating with respect to one another yet allow a smooth but firm transition when the boat seat or table is being slidably adjusted to its desired elevation. A split collar is attached to the outer tubular members and a threaded nut and rod assembly is engaged with the collar and has a handle or knob at the end of the rod as a mechanism for releasably frictionally locking the tubular members together when the accessory has been placed at the desired elevation. The rods located in the slots of the telescoped members prevent the members from rotating with respect to one another while permitting them to be lengthwise movable with little or no wobble. Conventionally, if needed, a mechanism may be coupled to the underside of the accessory for adjustably rotating the seat or table to a desired direction.  
           [0004]    As a further feature, the rods may be made long enough to rest on their bottom ends or, alternatively, the rods can be made shorter and held in place with a thin plastic sleeve between the two members having a series of through-slots generally corresponding to the dimensions of the shorter rods in the grooves of the telescoped members. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1 illustrates the conventional fashion in which a preferred embodiment of the invention is utilized;  
         [0006]    [0006]FIG. 2 is a section view showing detail of a preferred form of the invention;  
         [0007]    [0007]FIG. 3 illustrates detail of the releasable locking mechanism which can be utilized with a preferred form of the invention;  
         [0008]    [0008]FIG. 4 is a flat projection view of a retaining sleeve used in an embodiment of the invention; and  
         [0009]    [0009]FIG. 5 is a breakaway view showing detail of the invention utilizing a retaining sleeve. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0010]    As illustrated in FIG. 1, an outer hollow tubular member  10  is engaged at its lower end in a base member  11  which typically is attached in some fashion to a supporting surface such as a boat deck. Slidably telescoped within vertically oriented member  10  is a tubular support member  12 . Attached to the upper end of tubular member  12  is a flange or plate l 3  or some other convenient device, for attachment to the underside of a boat accessory such as a boat seat or a table. Flange  13  may include some type of mechanism for allowing the attached accessory to be turned to face in a desired direction. A knob or handle  14  may be made conveniently accessible for operating a releasable locking mechanism to hold the telescoped members in position when the boat accessory has been raised or lowered to its desired elevation. A suitable form of a locking mechanism is a split collar  15  which is attached by a bolt (not shown) or in some other convenient fashion to the upper end of outer member  10  for frictionally grasping interior member  12 . The manner in which the split collar operates to releasably lock the members in place is described later.  
         [0011]    Turning next to FIG. 2, the sectioned view shows the series of peripherally located spaced-apart elongated grooves or slots  18  on the outer surface of the interior telescoped support member  12  and corresponding elongated slots  19  circumferentially spaced around the interior wall of outer member  10  extending parallel to its axis. Located in the aligned spaces  18  and  19  is a set of elongated bearing rods  20  which rest within the generally circular grooves formed by the aligned slots  18  and  19 . Rods  20  are dimensioned to snugly or substantially fill the spaces and thereby prevent the two members  10  and  12  from rotating with respect to one another and are made of a material which produces a relatively smooth surface so that the two members can be smoothly slidably moved lengthwise with respect to one another with little or no wobble for adjusting the height of the boat seat or table or other device which is attached to support member  12 .  
         [0012]    As mentioned earlier, a split collar can be used to releasably lock the members in place. Collar  15  surrounds the upper end of member  10  and is attached rigidly to member  10  such as by a bolt or by welding (not shown). Alternatively, collar  15  can be molded or cast as an integral part of member  10 . In the embodiment illustrated collar  15  is attached to the upper end of member  10  and a thin gap or kerf slot  21  is cut out of member  10  which extends approximately half way around the outer periphery of member  10 . A vertical slot  32  is also cut out of member  10  so that the upper portion of member  10  which is surrounded by split collar  15  has some degree of flex and memory separate from the lower part of member  10 . Collar  15  has a split or gap  22  and a pair of radially extending ears  23  at each side of gap  22 . An elongated rod  24  with a handle or knob  14  at one end passes through suitable openings in ears  23 . The end of rod  24  opposite knob  14  is threaded to engage nut  25  which is attached to one of the ears  23  and a bushing  26  is rigidly attached to rod  24  and rests against the other ear  23 . Knob  14  can be manipulated to rotate rod  24  to thread it into nut  25  thereby causing bushing  26  to force the ears  23  to reduce gap  22  so that collar  15  squeezes down tightly against the top end of member  10  to cause it to frictionally engage inner member  12  thereby preventing member  12  from moving vertically when it has been adjusted to the suitable elevation. Knob  14  can be turned in the opposite direction to unthread rod  24  from nut  25  and thereby release the pressure of member  10  against member  12  and reduce the frictional engagement to permit further vertical adjustment between the two engaged members  10  and  12 . Other types of locking mechanisms can be utilized in conjunction with the telescoped members  10  and  12  with their associated grooves and bearing rods to releaseably lock the members when in the desired elevation. For example a retractable pin passing through outer member  10  into vertically spaced apertures in inner member  12  could be used. Other types of frictional releasable locking mechanisms may also be suitable for use.  
         [0013]    Bearing rods  20  may be made long enough so that they extend to the bottom end of member  10  and therefore are held in their vertical position by their lower ends resting against the interior of the base support or on the deck. However, shorter rods may be used and they may be kept in place by a thin plastic retaining sleeve  30  which is wrapped around inner member  12  and has a series of vertical slots  31  which are horizontally spaced corresponding to the location of grooves  18  and  19  so that rods  20  rest in slots  31  in sleeve  30  and are thereby held in their vertical location. Preferably sleeve  30  is severed and the two ends  30 A and  30 B extend out through gap  22  of collar  15  along the interior of ears  23 . FIG. 2 illustrates the invention without the retaining sleeve while FIGS. 4 and 5 illustrate an embodiment using sleeve  30 .  
         [0014]    [0014]FIG. 4 illustrates a typical plastic retaining sleeve  30  projected in a flat form. Openings  27  in ends  30 A and  30 B are to permit passage of shaft or rod  24  on locking handle  14 . As illustrated by partial breakaway view of FIG. 5, retaining sleeve  30  may be wrapped around vertical support member  12  with slots  31  in place for holding shortened rods  20  in place. The ends  30 A and  30 B of sleeve  30  are bent radially outward into gap  22  alongside ears  23  of collar  15  so that rod  24  passing through openings  27  holds sleeve  30  in place.