Abstract:
The apparatus according to this invention involves connection of a tubular bar ( 7, 9 ) with gripping features for the hands and behind the neck, to a tension resistant elastic rope for performing various aerobic exercises. The tension resistant rope is guided through to an opening in the tubular bar ( 60 ) which then joins to a newly designed retainer ( 30 ). The retainer includes a hole ( 40 ) for the elastic rope to feed through. As part of the retainer assembly, a fastener ( 32 ) is used to couple the elastic rope to the retainer. The improvement of the retainer features an extruded rectangular cut ( 41 ) allowing a lightweight and more robust mechanical linkage between the elastic rope and the tubular handle.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention generally relates to the technology for multi-purpose exercise. In particular, this invention relates to a new and improved joining feature of a tension resistant exercise apparatus. 
       BACKGROUND OF THE INVENTION 
       [0002]    The invention relates to a new and improved joining feature of a tension resistant exercise apparatus. The apparatus is used for multi-purpose exercises including strengthening and conditioning of the human body. Distinctively, the invention involves the mechanism and apparatus for joining a flexible/elastic rope to a tubular metal bar in the multi-exercise device. 
         [0003]    With perpetual advancements in the field of biology and kinesiology, exercise and health continue to be at the forefront of study and growth. Over the last twenty years a prodigious amount of exercise products have been introduced to the consumer market. In today&#39;s constantly evolving technology, there are new manufacturing methods and more effective technologies to enhance aerobics and exercise. Older exercise devices from years past are improving and updated to demonstrate safer and more effective exercise habits. 
         [0004]    Among the many exercise devices, is the tension resistant rope which joins to a tubular bar for performing strength resistant exercises. Consistent efforts are being made to improve the older methods of exercising equipment. One multi-purpose exercise device has gained a prodigious amount of popularity over the past twenty years: the tension resistant rope exercise device that couples to a tubular bar. While older patents exist for example, U.S. Pat. No. 4,733,861, to Plunkett, the complete disclosure of which is incorporated herein by reference, and which describes an exercise device comprising a pair of cylindrical handles coupled to an elastic cord that can be manipulated to modify the length and shape of the cord. Along with U.S. Pat. No. 5,746,687 to Vial, the complete disclosure of which is incorporated herein by reference, which also describes an exercise device comprising a pair of cylindrical handles coupled to an elastic cord that can be manipulated to modify the length and shape of the cord. 
         [0005]    The technologies described in the aforementioned patents are out dated, the advancement of technology and exercise methods presented by professional fitness advisors, continues to urge designers of exercise equipment to update features on older equipment and provide safer and more effective exercise techniques to keep up with evolving discoveries of exercise and innovation. 
         [0006]    As applications have been made by designers to produce more effective and safe exercise equipment, the concern perpetually exists regarding robust and effective designs for multi-purpose exercise equipment. With a prodigious amount of information available to consumers including the accessibility of information on the internet, libraries, television etc., and the consumer is able to access the requirements for modern day exercise equipment i.e. feeling the exercise equipment is safe, comfortable and effective. The new designs must be able to withhold higher tension compared to the original designs from years past along with defined safety measures in place to make the users feel comfortable when using the equipment. 
         [0007]    The technology involved with the joining method of the tubular bar to the elastic rope continues to evolve in this specific type of multi-purpose exercise equipment. The joining intersection creates principal stresses in the linking members inside the metal tubular bar and the elastic rope. Along with these stresses, there are tensile stresses exerted by the user of the equipment that apply to the mechanical joining of the tubular bar and the elastic rope. The principle in designing the mechanical joining is one the most important features of the multi-purpose exercise equipments. Along with joining, the weight and safety of the exercise is another important factor for multi-purpose exercise equipment. The perpetual application and wearing of the elastic rope when coming in direct contact to the metal material of the tubular bar has caused injuries in previous designs as the tensile stresses have eventually caused the elastic rope to snap and fail. With a robust mechanical joining, the safety measures can be met along with obtaining the most effective results for the user. 
       SUMMARY OF THE INVENTION 
       [0008]    The invention is directed to a method and apparatus for coupling a tubular bar of an exercise device to a flexible line, such as an elastic rope. The present invention provides a relatively strong mechanical link between the handle and the flexible line that will effectively withstand the concentrated stress placed on the link during use of the exercise device. The newly designed retainer with the extruded cut feature allows for an improved lightweight component to be used in the coupling assembly. In addition, the present invention is configured to reduce contact between the flexible line and the handle, thereby minimizing stress on the line. 
         [0009]    The apparatus comprises at least one rigid bar of an exercise device and an elastic flexible line having an end portion extending through a circumferential opening in the handle. The flexible line is secured within an inner lumen of the handle by a joining assembly. A joining assembly comprises a retainer positioned within an inner lumen of the handle and defining a hole for receiving the end portion of the flexible line. The retainer is designed for manufacturability of injection molding by including a 3-point curved cut out feature which also allows for a more rigid and lightweight component of the joining assembly. The coupling assembly further includes a fastener for securing the end portion of the flexible line to the retainer to thereby fix the line to the handle. 
         [0010]    The method includes the retainer which slides into the open end of the bar. In addition, the retainer defines a lip projecting from one of its surfaces around the hole. The lip is sized to minimize contact between the flexible line extending through the hole and the bar. This reduces the surface friction between the handle and the line, thereby decreasing the wear on the line. 
         [0011]    The fastener is preferably a conically shaped screw having a first end extending through an open end of the flexible line. The screw comprises a second end with a larger diameter than a diameter of the retainer hole for inhibiting the screw from passing through the retainer hole to thereby prevent the flexible line from being released from the retainer. Preferably, the second end comprises a protruding lip that mates against the retainer wall to prevent passage of the screw through the retainer hole. The retainer, including the new and improved extruded rectangular cut out provides optimum joining between the screw and elastic rope. This is done by embedding the joining of the tubular bar to the elastic rope in a particular housing within the retainer. The extruded cut feature is makes the retainer lightweight. The half arc protrusion added on the opposite end of the extruded cut allows for balancing of the retainer component. The screw may also include a ridge protruding from the screw and forming a spiral shape towards the first end of the screw for gripping onto an inner wall surface of the flexible line. This spiral ridge digs into the flexible line, providing a strong mechanical link there between. 
         [0012]    The method of the present invention comprises directing an end portion of the flexible line through the circumferential opening in the handle and guiding the end portion through a hole in the retainer. The end portion is then fastened to the retainer and the retainer is positioned within the inner lumen of the handle to thereby fix the flexible line to the handle. Preferably, the end portion of the line is fastened to the retainer by inserting a first end of the conical screw through an open end of the flexible line and gripping the inner wall of the flexible line with a spiral ridge protruding from the screw. One of the advantages of this method is that the screw and the retainer can be easily replaced by engaging a lip on the screw with, e.g., a pair of pliers, withdrawing the screw from the flexible line and guiding the line back through the hole in the retainer. Features and advantages of the improved retainer will appear from the following description in which the preferred embodiment has been set forth in detail in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of an improved multi-purpose exercise device incorporating a coupling assembly according to the principles of the newly designed exercise device. 
           [0014]      FIGS. 2A-2B  are schematic views illustrating various exercises performed with the improved exercise device of  FIG. 6 . 
           [0015]      FIG. 3A-3C  are side views of the improved coupling assembly of  FIG. 7 , illustrating the method according to the improved invention of coupling a flexible elastic line to a rigid bar using the method of coupling. 
           [0016]      FIG. 4A-4C  is isometric views of the improved invention of the retainer component illustrating the extruded cut feature along with the protrusion of the half arc semi-circle. 
           [0017]      FIG. 5  is a perspective view of a fastener of the coupling assembly of  FIGS. 3A-3C . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]    Referring to the drawings in detail, wherein like numerals indicate like elements, a multi-purpose exercise device  3  is illustrated in  FIG. 6  according to the principles of the invention. Exercise device  3  generally includes a pair of rigid gripping handles  7 ,  9  with a center bar  11  and attached to an elastic flexible line  10 . 
         [0019]    Referring to FIGS.  6  and  8 A- 8 C, handles  7 ,  9  each comprise an elongated cylindrical body  11 , preferably constructed of metal, such as aluminum or stainless steel. Preferably, cylindrical bodies  11  on both ends have substantially identical diameters and lengths to facilitate use of the device when handles  7 ,  9  are separated from bar  13 . Center bar  8  includes a release button  14  for releasably attaching handles  7 ,  9  to center bar  13 . Release buttons  14  on both sides include compressed springs (not shown) having protrusions that extend through corresponding holes in handles  7 ,  9 , to lock the handles to center bar  13 , thereby preventing them from rotating relative to bar  13  and pulling apart from the center bar. Release buttons  14  on both sides allow the operator to either use device  3  as a composite bar (as shown in  FIG. 6 ) or to separate handles  7 ,  9  from center bar  13  for a variety of other exercises. 
         [0020]    Referring to FIGS.  6  and  8 A- 8 C, handles  7 ,  9  each comprise an elongated cylindrical member  11 , preferably constructed of metal, such as aluminum or stainless steel. The cylindrical member has an arched center for placing behind the neck of the user as grip and guide for performing various aerobic exercises. 
         [0021]    Center bar  11  is a metal cylindrical bar having an arched center for balancing the left and right ends of the bar center to the user&#39;s neck. Handles  7 ,  9  and center bar with arched center may also include grip sleeves  13  made out of an elastomeric material, such as rubber, for facilitating operator gripping of the handles  7 ,  9  and center bar  11  during use of exercise device  3 . Preferably, the composite length of bar  11  and handles  7 ,  9  when coupled together as shown in  FIG. 6  is approximately equal to the shoulder span of an adult. 
         [0022]    Line  11  is removable coupled to line receiving ends  26 ,  15  of handles  7 ,  9  by a coupling assembly  24 , described in more detail below (see  FIGS. 8A-8C ). Line  11  may be a solid or tubular rubber, latex or any other suitable elastic flexible material which will not be permanently deformed upon the full extension of the user&#39;s arms, such as elastic synthetic rubber, elastic nylon cord or other elastic cording. Line  10  will preferably have a sufficient length, in a non-stressed configuration, so that the distance from the handles  7 ,  9  to the middle of the line is slightly less than the waist height of an operator. The length of line  10  may also be varied by the user to produce the desired resistive or tension force to the displacement of handles  7 ,  9 . As shown in  FIGS. 8A-8C , the line preferably has open ends  24  and inner lumens  26  in communication with the open ends  24  (note that only one open end and inner lumen is shown in  FIGS. 8A-8C ). Line  10  may also include a solid rubber or nylon insert extending through the outer tube between the inner lumens  26  on either end of the line. 
         [0023]    Referring to  FIG. 6 , the exercise device  3  may be used for a variety of muscle development and/or aerobic exercises. An operator may lie on the line  10  or position the line underneath a chair to perform muscle development exercises, such as the military press or the bench press (see  FIGS. 7A ). Alternatively, the device may be used for an aerobic type exercise. For example,  FIG. 7B  illustrates two operators using the exercise device as a rowing machine. 
         [0024]      FIGS. 8A-8C ,  9 A- 9 C, along with the spiral fastener of  FIG. 5  illustrate the new and improved invention of the novel apparatus and method for coupling line  10  to handles  7 ,  9  of the present invention. Coupling assembly  24  comprises a retainer  30  ( FIG. 9 ) and a fastener  32  ( FIG. 5 ). Retainer  30  includes an elongate body member  33  preferably constructed of molded plastic and having a planar wall  34  and an opposite arcuate wall  36 . Retainer  30  includes a protruded circular feature  39  from the planar surface. Retainer  30  also includes a rectangular featured cut out  41  extending to an end portion of Retainer  30 . The combination of the protruded circular feature on one end of the retainer and the extruded cut on the other end completes the improved design of the retainer component in the coupling assembly. Retainer  30  enters into one of the handles  7 ,  9 , as discussed below. Retainer  30  further includes a hole  40  extending through body member  33  and having a larger inner diameter than the outer diameter of line  10  so that line  10  can be inserted through hole  40 . 
         [0025]    Retainer  30  includes a raised lip  42  protruding from arcuate wall  36  and extending around the circumference of hole  40 . Lip  42  functions to minimize contact between the point on line  10  where pressure is applied and the inner metal surface of the handles after the handles have been coupled to line  10 . Thus, when an operator pulls on the elastic line, the tensile force causes the line to rub or wear against the plastic retainer, rather than the metal handle. The friction between the plastic retainer and the elastic line is substantially less than the friction between the metal handle and the elastic line. The extruded cut feature  40  in the retainer  30  allows for a closer contact for joining between the elastic rope and the spiral fastener. This helps increases the lifetime of the line  10 , thereby minimizing potential injuries caused by the failure of line  10   
         [0026]    Referring to  FIG. 5 , fastener  32  is preferably a screw that functions as a stopper for preventing the release of line  10  through hole  40  in retainer  30 . To that end, fastener  32  comprises a generally conical body  46  with a stopper disc  48  at one end. Disc  48  has a larger outer diameter than the inner diameter of hole  40  so that fastener  32  cannot be pulled through hole  40 . Disc  48  further includes a lip  50  protruding outward there from to facilitate gripping of fastener  32  with, for example, a pair of pliers. To facilitate the connection between fastener  32  and flexible line  10 , fastener  32  includes a ridge  52  protruding outward from conical body  46  in a spiral shape. Ridge  52  grips the inner surface of line  10  to resist tension as the line  10  is pulled away from fastener  32  during use of the device. 
         [0027]    Referring to  FIGS. 8A-8C , the method for coupling line  10  to handles  7 ,  9  described in detail is as follows. Line  10  is fed through a circumferential opening  60  in body  12 , directed through an inner lumen  62  and out of line receiving end  20  of handle  4 , as shown in  FIG. 8A . Line  10  is suitably bent to form a partially kinked portion  64  near open end  24  to facilitate holding line  10  within inner lumen  62  of handle  4 . As shown in  FIG. 8B , retainer  30  is positioned with arcuate wall  36  facing line  10  and line  10  is guided through hole  40  in retainer  30 . Lip  50  of fastener  32  can then be grasped by suitable means, e.g., pliers, and conical body  46  is compressed into lumen  26  of the elastic line  10 . The extruded cut feature of the retainer  30  allows for optimum joining of the Lip  50  and conical body  46 . The spiral ridge  52  on fastener  32  grips the inner surface of line  10  to bond fastener  32  to line  10 . 
         [0028]    As shown in  FIG. 8C , line  10  is pulled taut until fastener  32  engages planar wall  34  of retainer  30 , thereby preventing further pulling of line  10 . Coupling assembly  24  is then guided into the open end of line  10 . The kinked portion  64  of line  10  and the lip  50  of fastener  30  provide a frictional fit with the inner walls of handle  4  so that elastic line  10  cannot be pulled further through circumferential opening  60 . If the kinked portion  64  unravels, however, retainer  30  will not be pulled through opening  60  and fastener  32  ensures that line  10  remains fixed to the retainer  30 . After the line  10  and coupling assembly  24  are suitably positioned within handle  4 , a cap  70  may be placed over open end  20  to seal coupling assembly  24  within the handle. 
         [0029]    Although one or more embodiments of the newly improved invention have been presented in detail, one of ordinary skill in the art will appreciate the modifications to the components. It is acknowledged that obvious modifications will ensue to a person skilled in the art. The claims which follow will set out the full scope of the claims.