Abstract:
Handles providing shock absorption are provided. In some embodiments, handles comprise: a handle core having an axis; core permanent magnets mounted to the handle core; a handle sleeve surrounding the handle core; sleeve permanent magnets mounted to the handle sleeve which generate repelling forces radial to the axis from at least some of the core permanent magnets; and an adjustment screw used to control a force longitudinal to the axis.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application claims the priority under 35 U.S.C. § 119 to European Patent Application No. EP06010026, filed May 16, 2006, which is hereby incorporated by reference herein in its entirety. 
   TECHNICAL FIELD 
   The disclosed subject matter relates to handles providing shock absorption. 
   BACKGROUND 
   Sports involving the use of rackets (e.g., such as tennis, racket ball, squash, badminton, etc.), clubs (e.g., such as golf, etc.), bats (e.g., such as baseball, cricket, etc.), sticks (e.g., hockey, lacrosse, etc.), and other similar devices are widely practiced around the world. When used, these devices frequently impact a ball, shuttlecock, puck, or other item, resulting in sharp vibration and impact forces to the users hands and arms. These forces can irritate or injure the user. 
   SUMMARY 
   Handles providing shock absorption are provided. In some embodiments, handles comprise: a handle core having an axis; core permanent magnets mounted to the handle core; a handle sleeve surrounding the handle core; sleeve permanent magnets mounted to the handle sleeve which generate repelling forces radial to the axis from at least some of the core permanent magnets; and an adjustment screw used to control a force longitudinal to the axis. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a cross-sectional diagram of different views of a handle in accordance with some embodiments. 
   

   DETAILED DESCRIPTION 
   Handles providing shock absorption are provided. In some embodiments, these handles have magnetic fields generated therein by permanent magnets to dampen the shock when using a racket, club, bat, etc. on which the handles are located. While the handles are described below in connection with a tennis racket, it should be apparent that these handles can be used on any type of device, including those for other sports, those for tools (e.g., hammers, pneumatic wrenches, etc.), and any other handle that transfers shock or vibration to a user&#39;s hands. 
     FIG. 1  shows a handle  3  of a tennis racquet comprising a handle sleeve  4  having a hollow space  4  in which contact-free permanent magnets are located which are poled such that repelling magnetic fields are created. Vibrations are absorbed by the non-contacting state of the magnets and the floating state of the generated magnetic fields. The strength of the magnetic field can be regulated by means of the adjustment screw  29 . 
     FIG. 1  further explains in detail the handle design comprising magnets situated in the handle sleeve  4 . Pole  27 B of magnet  27  versus pole  28 B of magnet  28  generates a floating state by homo-polarity between the handle  3  and the handle implement sleeve  4 . From the start, the sleeve  4  is pressed so much over magnet positions  46  and  48  that the repelling magnetic fields  36  press the sleeve  4  so far in the direction  45  with the magnets  23 ,  24 ,  30 , and  31  until the counter-pressure between magnets  27  and  28  is built up in an equalizing manner via the magnetic fields from poles  27 B and  28 B and the counter-pressure at the end face is built up at the same time, as Drawing B shows. The handle sleeve  4  with the magnets  24  and  25  and magnets  30  and  31  is moved in the direction  35  by the regulation of the adjustment screw  29  with the magnet  28  upwardly to the magnet  27  so that the magnet systems approach the strongest floating force between two positions  46  and  48  from the standing position  45  in the direction  47 , so that a contact-free regulation of the floating force  36  is present between the sleeve  4  and the handle part  3 . 
   In response to further adjustment of the sleeve  4  by means of screw  29  in the direction  35  over the highest magnetic force between two points  46  and  48  in direction  47  has taken place, the sleeve  4  leaves the floating state in the direction  35 , whereby the sleeve  4  can be released from the handle  3  and can be replaced. The magnet arrangements  38  and  42  and  40  and  41  in axis  2 Z, and magnets  37  and  39  serve the lateral guidance of the handle  3  in the sleeve  4 , and act against one another to ensure the floating state in all directions. Main force magnetic combinations  23  and  24 ,  25  and  26 ,  30  and  31 , and  32  and  33  are attached in the main ball hitting directions  50 . Further vibration damping combinations are possible by combinations of springs  49  and different present magnetic arrangements. 
   All magnet arrangements are attached, as in sketch D, in repelling manner so that, for example, pole  23 A of magnet  23  and pole  26 A of magnet  26  are opposed to one another in a homo-polar manner and repel. This repelling force, which acts oppositely to the force created by magnets  30  and  31  (which have the same polar arrangement), results in a floating state due to the force of the magnetic fields with the same magnetic field strengths of the magnets of the handle  3  and the sleeve  4 . These forces absorb vibrations during the course of a game in which the racket is used. 
   The following reference numerals are used throughout the figures.  1 —racket strings;  2 —racket frame;  3 —racket handle;  4 —racket handle sleeve;  23 ,  24 ,  25 ,  26 ,  27 ,  28 ,  30 ,  31 ,  32 ,  33 —permanent magnets;  23 A,  26 A,  27 B,  28 B—south pole representations;  23 B,  26 B,  27 A,  28 A—north pole representations;  27 ,  28 —necessarily round magnets;  29 —adjustment/regulation screw for damping strength in direction  34  or  35 ;  34 —direction of movement of handle sleeve  4  for weaker damping density  36  when  3  and  4  are positioned as shown in Drawing B;  35 —direction of movement of handle sleeve  4  for stronger damping density  36  when  3  and  4  are positioned as shown in Drawing B;  36 —magnet field density is the magnetic pressure strength between similar magnetic poles (i.e., south and south, or north and north) and/or clearance for spring systems  49 ;  37 ,  38 ,  39 ,  40 —permanent magnets for lateral guidance of sleeve  4  to handle  3 ;  41 ,  42 —counter-magnet to  38  and  40  for lateral guidance for  3  to  4 ;  43 ,  44 —counter-magnets to magnets  37  and  39 ;  45 —direction of movement of the handle  4  and the magnets  23 ,  24 ,  30 ,  32  when the handle sleeve  4  is positioned on handle  3  as shown in Drawing B up to the counter-pressure of the magnets  27 ,  28 ;  46 —position of the highest mutual magnetic force on  48  (maximum floating force between all magnetic systems in the handle  3  to the handle sleeve  4 );  47 ,  35 —direction of movement of the magnets  23 ,  24 ,  30 ,  32  for handle replacement and the mutual magnet field strength change over  27 ,  28  and  29 ;  48 —fixed positions of the magnets  25 ,  26 ,  31 ,  33 , on handle  3 ;  49 —spring systems of all types; and  50 —main stroke execution direction. 
   Although the invention has been described and illustrated in the foregoing illustrative embodiments, it is understood that the present disclosure has been made only by way of example, and that numerous changes in the details of implementation of the invention can be made without departing from the spirit and scope of the invention, which is only limited by the claims which follow. Features of the disclosed embodiments can be combined and rearranged in various ways.