| 摘要 |
PURPOSE: To easily recognize whether or not the continuous movement of a player is performed without errors by quickly responding to the entire movement of a hitting rod and generating signals perceivable during the entire movement to the hitting of a ball by a small number of signal generation switching elements. CONSTITUTION: In a swing-out phase in a direction E, a magnet 131 is moved toward a lead switch 130. Corresponding to the acceleration of swing-out, one or plural or all of switches 130 are closed. Simultaneously, the magnet 139 is moved toward the lead switch 138 and the direction of swing-out movement is controlled. Further, the magnet 135 is retained at the terminating position inside a truck 136. The length of the movement of the magnet 139 for driving the switch 138 is put in a microprocessor 121 and thus, the length of the swing- out phase is stored as a program. The magnet 129 drives the lead switch 128 and thus, the positioning of a racket in the entire swing-out phase or in a following ball hitting phase is put in the program. |
