| 摘要 |
PURPOSE:To prevent biassed abrasion by installing a non-circular gear intermeshing mechanism, an acceleration ratio of which is increased with revolution in the closing direction of a door, into a speed-up wheel row accelerating the turn of an output shaft and transmitting the turn over a control means. CONSTITUTION:The large diametral section of a partial helical gear 15 is engaged with the small diametral section of a partial helical gear 11, a pinion 3c moves a slider 4 to the left through a rack 4a, springs 10, 10 are push-shrunk and energy-stored, and the slider 4 is energized in the direction of door-closing. The speed of the revolution of an input shaft 3 is increased and the revolution is transmitted over the gear 15 through the gear 11, and the acceleration ratio of the input shaft 3 is accelerated with the progress of the rotation of both gears 11, 15, rotation in the direction of door-closing. When the engagement of the gears 11, 15 is changed, a gear ratio is elevated gradually, and the acceleration ratio of the turn of the output shaft 3 is increased with revolution in the direction of door-closing. When braking force is augmented, the speed of door-closing is decelerated gradually with the reduction of door opening because the speed of revolution of the output shaft 3 is decreased slowly, and both gears 11, 15 are stopped at mutually engaged positions when a door is brought to a closed state. |
