SPEED CHANGE GEAR AND CONTINUOUS SPEED CHANGE GEAR CONSISTING OF HIGH-SPEED UNIT

摘要

A speed change gear of the invention is provided with two planetary gear sets, each of which has a sun gear (11G) on the inner side and planetary gears (21, 22, 23) and ring gears (15, 18) on the outer side. An input shaft (11) is connected to the sun gear (11G) in the first planetary gear set. Both of planetary gear carriers (13, 17) are coupled together by planetary gear shafts (20, 24) so that the planetary carriers are rotated at the same speed, and the planetary gears are constructed so that they rotate freely on their own axes and revolve together with the planetary gear carriers around the planetary gear shafts. An output shaft (14) is coupled integrally with the ring gear (15) in the second planetary gear set, and the planetary gear (21) meshed with the sun gear (11G) on the input shaft is meshed with the planetary gear (22) in the second planetary gear set, said gear (22) being meshed with the ring gear (15) on the output shaft, so that the transmission of power is effected. The rotation of the ring gear (18) in the first planetary gear set is controlled by applying rotational resistance to said gear, thus varying the gear ratio. Since a high-speed unit (3) is provided to increase the number of revolutions per minute of the input shaft, the output shaft can be rotated more speedily than the input shaft by transmitting the rotational force of the high-speed unit to the planetary gears in the second planetary gear set.