| 摘要 |
PROBLEM TO BE SOLVED: To improve assemblability, to fulfil the demand of making the machine compact and to surely detect an ejected ball without impairing ejecting stability. SOLUTION: With a reflection type photo switch 25 attached to a body frame 11, the inner face of a rail guide 26 oppositely facing the switch is made an optical reflection face. Ordinarily, a light beam from a light emitting element 30, reaching the rail guide 26, is reflected with a part of its reflection light received by a light receiving element 31, which passes into ON state (undetected state of ejected ball) Subsequently, with an ejected ball 37 blocking the angle of visibilityθ2 of the light receiving element 31, it is switched to OFF state (detected state of ejected ball). After that, with the ejected ball 37 getting out of the angle of visibilityθ2 of the light receiving element 31 and blocking the angle of visibilityθ1 of the light emitting element 30, the light beam from the light emitting element 30 is prevented from reaching the rail guide 26, so that the light receiving element 31 is continuously kept under OFF state.
|
