| 摘要 |
<p>To permit installation of a bowling ball return chute between a pair of alleys, and prevent interference of bowling balls admitted from either adjacent alley to the chute, the alleys are formed with openings which are blocked by doors, the doors each including an interlock mechanism mutually engageable with the interlock mechanism of the other so that, upon opening of one door due to pressure of a ball thereagainst, the other door is locked and admission of a ball from the other alley is prevented. The ball is then moved on a rocker which deflects due to the weight of the ball, the deflecting movement being re-transmitted to the previously opened door to close the door, so that a ball from the other alley can then be admitted, the doors being easily opened by impingement of the balls thereagainst. The doors are held in locked position by a lock mechanism which is unlocked by a feeler located to be engaged only by bowling balls, and not by the smaller bowling pins, preferably over a timer mechanism which permits opening only a predetermined time after a bowling ball has been played so that tossed pins cannot inadvertently engage the feeler, and hence permit spurious opening of a door. -1a-</p> |
