Abstract:
A stave press assembly for holding a wooden stave or other work piece while the stave is fabricated into a bow or other operations are performed on the work piece, has an immovable pressure plate disposed nominally horizontally when the press is attached to a support surface, and a movable pressure plate which can grip an irregularly shaped wooden stave or other work piece by moving it in a downwardly direction toward the immovable pressure plate. The movable pressure plate is pivotable to a limited extent in order to provide a gripping surface for irregularly shaped items and each pressure plate is lined with resilient high friction material.

Description:
CLAIM OF PRIORITY OF NON-PROVISIONAL APPLICATION 
   The present application claims the priority of provisional application Ser. No. 60/686,359, filed on Jun. 1, 2005 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is in the field of bow making equipment. More particularly, the present invention is in the field of equipment particularly suitable for making self bows from a stave of suitable wood. Still more particularly, the present invention is directed to a press designed to hold a stave of wood while a bow is being made from the stave. 
   2. Brief Description of Background Art 
   The sport of archery has gained tremendous popularity in the United States of America and in many other countries as well. Bows and arrows are used in an ever increasing number for target shooting (field archery) and for hunting as well, so much so that most states of the United States of America have a special bow hunting season for big game separate from the rifle hunting season for the same game. 
   One type of presently used archery equipment is based on high technology and involves the use of modern plastic materials such as KEVLAR™, fiber glass or the like for the bow limbs and also cams or the like which substantially reduce the force at which the bow needs to be held while pulled back relative to the maximum pull weight of the bow. This reduction of force is normally termed in the trade “let down”. Bows which can be operated with a “let down” are known in the trade as compound bows. 
   In spite of the availability of the above-noted “high technology” compound bows traditional archery equipment is also popular and used for target shooting and hunting as well. Generally speaking, a bow is considered “traditional” if it lacks “let down”, that is any equipment that would reduce the holding weight of the bow relative to its maximum pull weight. Many traditional bows are still products of modern technology and contain advanced materials such as fiberglass carefully laminated and glued together with wood to form the limbs of the bow. 
   Still another class within the broader class of traditional bows is formed by bows which do not have laminated limbs containing any modern material but rather are made entirely of wood. Such bows are usually termed ‘self-bows” and are usually made from a stave of suitable wood. Yew and osage orange serve as examples for trees from which suitable staves for bow making can be obtained, although there are many other species of trees also suitable for this purpose. Self-bows are made by craftsmen specialized in this trade and also by individuals who make the bows as a hobby, and as a matter of self improvement and pride of their own accomplishment. 
   Making a bow from a suitable stave involves many steps which include forming the stave with a rasp, draw knife, saw, sandpaper and the like into the desired shape. For this and other operations involving cutting, sanding, polishing it is necessary to hold the stave rigidly in a press or vise. The current most common way for bowyers as well as hobbyist making self bows is to squeeze and hold the stave in an ordinary vise that typically has jaws that expand or come together in the horizontal direction. While making self bows there are several important problems occasioned with the use of this type of common vise. 
   The standard vise has parallel jaws that do not conform to irregularly shaped wood such as a stave from which a self-bow is to be made. This results in the vise crushing the wood grain as the user tightens the jaws to grip the stave tight enough so the user can work on it. 
   Additionally, jaws of a standard vise are relatively small. They do not provide enough surface area resulting in very high pressure per square inch (psi) bearing on the delicate wood and crushing the wood fibers. However, in order to have a long lasting and well functioning self bow the fibers of the wood must remain intact. 
   Another disadvantage of using a standard vise for self-bow making is that the jaws grip the wood from the sides only. Therefore, when a bowyer bears weight or force down on the stave from the top, as he often needs to do while making the bow, the weight or force tends to pry the wood out of the vise. The present invention solves the foregoing problems. 
   Still another disadvantage of using a standard vise for self-bow making is that the jaws of the standard vise do not pivot. This again makes the grabbing of irregularly shaped wood, such as stave for bow making, difficult and results in inadequate holding of the stave and or in crushing of wood fibers. 
   The above-noted disadvantages of a standard vise are also applicable to wood and other work pieces which need to be held without damage to their surface area and on which force, such as cutting, drilling, rasping, polishing and the like is applied in a substantially vertical direction. 
   OBJECTS AND SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide a press that is optimally suited for holding a stave while a self-bow is being manufactured from that stave. 
   This and other objects and advantages are attained by a press that comprises a nominally horizontally disposed base plate and suitable mechanical means for attaching the base plate to a support surface such as a post or a table top. The base plate includes an interior surface lined with high friction and preferably resilient material. The base plate lined with the high friction material serves as an immovable pressure plate of the stave press of the present invention. 
   Nominally upright side members are fixedly attached to the base plate on two of its sides and a cover member is attached to the upright members thereby forming an opening into which an object, such as a stave, can be placed horizontally. A threaded hole is located in the cover member and a threaded bolt is engaged in the threaded hole, the bolt being capable of up and down movement within the opening as a result of being turned about its longitudinal axis. A solid plate also lined with high friction and preferably resilient material on its interior surface facing the immovable pressure plate is attached to the end of the threaded bolt by means that allow limited tilting in up and down direction of the solid plate. The means for limited tilting usually comprise a ball joint by which the solid plate is attached to the threaded bolt. The solid plate acts as a movable pressure plate of the stave press and can be moved up and down by turning the threaded bolt and can be pressed tightly against a stave, even when the stave is of irregular shape, to hold the stave firmly while a person works on the stave. Each of the lined high friction surfaces of the pressure plates of the stave press have at least 25 square inch area, whereby the pressure per surface unit (psi) is substantially decreased relative to an ordinary or common vise and the stave press still holds the stave very firmly. 
   The press of the present invention can also be used for firmly holding a work piece, wood, metal or plastic, without damaging its surface and rendering it practical to apply substantially vertical force to the work piece while performing such operations as cutting, drilling, rasping, polishing and the like. 

   
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       FIG. 1  is a perspective view of the stave press of the present invention holding a stave. 
       FIG. 2  is another perspective view of the stave press of the present invention holding a stave. 
       FIG. 3  is an end view of the stave press of the present invention holding a stave. 
       FIG. 4  is a perspective view of the stave press and of the mechanical means used to attach the stave press of the present invention to the support base. 
       FIG. 5  is a side view, partly in perspective of the stave press of the present invention. 
       FIG. 6  is a cross-sectional view, the cross section being taken on lines  6 , 6  of  FIG. 5 . 
       FIG. 7  is another cross-sectional view, the cross section being taken on lines  7 , 7  of  FIG. 5 . 
       FIG. 8  is an enlarged partial view of the area indicated on  FIG. 7 . 
       FIG. 9  is another enlarged partial view of the area indicated on  FIG. 7 . 
       FIG. 10  is a cross-sectional view showing how the stave press holds an irregularly shaped stave. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The following specification taken in conjunction with the drawings sets forth the preferred embodiment of the present invention. The embodiment of the invention disclosed herein is the best mode contemplated by the inventor for carrying out his invention in a commercial environment, although it should be understood that various modifications can be accomplished within the parameters of the present invention. 
   Referring now to the drawing figures, the stave press assembly  20  of the present invention is disclosed. With primary reference to  FIGS. 4 and 5  the stave press assembly  20  includes a mounting base  22  which, when the stave press  20  is mounted in the regular way for use, is disposed nominally horizontally. 
   A cylindrical member  24  is fixedly attached to the mounting base  22 . The mounting base  22  and the cylindrical member  24  serve for mounting the stave press  20  to a support base  26  such as a table or work bench. The mounting base  22  includes a plurality of holes  28  through which the mounting base  22  can be attached to the top of the table or workbench  26  by screws  30 . Alternatively, the mounting base  26  can also be attached to a workbench  26  (or the like) with clamps (not shown). 
   The attachment of the mounting of the base  22  and thereby the entire stave press assembly  20  to the table or workbench  26  with screws  30  is shown in  FIGS. 1 and 2 . These figures illustrate in an exemplary manner that the stave press assembly  20  can be mounted in different positions to the table or work bench  26  at the option of the user (not shown). 
   Referring now primarily to  FIGS. 4 ,  5  and  6  the stave press assembly  20  includes base plate  32  on the bottom side of which a hollow cylindrical member  34  is attached. The hollow cylindrical member  34  is dimensioned to engage with a tight but removable fit the cylindrical member  24  of the mounting base  22 , as best shown in the cross-sectional view of  FIG. 6 . The hollow cylindrical member  34  can be rotated relative to the solidly mounted cylindrical member  24  of the mounting base  22 , as shown in  FIG. 6 , thereby providing a further option to the craftsman (not shown) to place the stave press assembly  20  in a desired position. 
   Two or more bolts  36  are engaged in spaced threaded holes  38  of the hollow cylindrical member  34 . The bolts  36  when tightened against the cylindrical member  24  of the mounting base  22  mount the entire stave press  20  to the mounting base  22  which is itself solidly mounted to the workbench  26  (or the like) in the manner described above. Thus, the mounting base  22 , hollow cylindrical member  34  and the bolts  36  serve as mechanical means for attaching the stave press assembly  20  to a support  26 . Other mechanical means, for example a plate (not shown) that is secured to the side of a table or of a workbench could also be used for this purpose. Still other mechanical ways, per se well known in the art, could be used to attach the stave press assembly  20  to a support  26 . 
   Upright side members  40  are affixed to the base plate  32  of the stave press  20  and a cover or top member  42  is affixed to the side members  40  so that the combined base  32 , side members  40  and cover or top  42  form an opening into which an object, such as stave  44  of wood (shown in  FIG. 1 ) can be placed in a nominally horizontal direction. 
   The cover or top member  42  includes a hole  46  which accommodates a threaded bolt  48 . In the herein described preferred embodiment additional material  50  is welded to the cover or top member  42  to reinforce the hole  46 . Threads which engage the threaded bolt  48  are provided in the extra material  50 . This is shown in  FIG. 8 . The threaded bolt  48  includes a lever  52  on one end. The lever  52  renders it easy to turn the bolt  48  with substantial force. 
   A solid plate  54  is attached to that end of the bolt  48  which is within the opening formed by the combined base  22 , upright side members  40 , and top or cover member  42 . The solid plate  54  serves as the upper movable pressure plate of the stave press  20 . The upper pressure plate  54  is attached to the bolt  48  in such a manner that the upper pressure plate  54  can pivot within a limited range in an up and down direction. This is accomplished by having a swivel foot  56  welded to the top of the movable upper pressure plate  54 . The swivel foot  56  includes a hole  58  specially formed to accommodate a ball  60  that is at the end of the threaded bolt  48 . These features can be best seen on  FIG. 9 . Thus, the upper pressure plate  54  is mounted to the bolt  48  with ball joint. The advantage of this arrangement is that the stave press  20  is capable of conforming, in a limited sense, to staves  44  of irregular shape. This is an important feature of the present invention because most staves  44  are of somewhat irregular shape and solidly holding such staves  44  in the stave press  20  is important for the craftsman (not shown) who works on the stave  44 . 
   Generally speaking, the stave press assembly  20  is made from steel and where necessary the various parts are attached to one another by welding. 
   Referring now primarily to  FIGS. 4 ,  5 ,  7  and  10  high friction and preferably resilient material  62  is shown to line both the immovable base plate  32  and the movable pressure plate  54 . Rubber serves a suitable material for this purpose. Thus, rubber pads  62  of approximately ⅜ inch thickness are glued to the interfacing pressure plates  32  and  54 . Instead of rubber other resilient plastic materials of relatively high surface friction can also be used as the resilient lining of the plates  32  and  54 . It is a special feature of the present invention that the surface area of each of the pressure plates  32  and  54  is relatively large, at least 25 square inches of larger. In the presently preferred embodiment the surface area of each rubber pad is approximately 34 to 35 square inches. This large surface area, the resilient high friction rubber lining  62  and the ability of the upper pressure plate  54  to pivot and accommodate irregularly shaped staves  44  work together to provide a very strong grip on a stave  44  of wood without crushing the fibers of the wood.  FIG. 10  shows a stave  44  for making a self bow (not shown) solidly held in the stave press assembly  20  of the present invention. 
   Those skilled in the art will readily understand that the press of the present invention can also be used for firmly holding any work piece, wood, metal or plastic, where it is desired to keep the surface of the work piece unblemished and to perform operations such as cutting, drilling, rasping, polishing and the like which include an application of force in the substantially vertical direction.