| 摘要 |
1488673 Change-speed gear KER-TRAIN SYSTEMS NV 17 Sept 1974 [26 Sept 1973 11 Sept 1974] 40359/74 Heading F2D An infinitely variable transmission comprises a spool rotatable by an input shaft and carrying a plurality of gear train loops arranged around the input shaft axis and sharing common first and last gear elements, each loop including a differential gear train, an overrunning clutch, at least two pairs of variable-ratio gears, i.e. gears of non-circular form, and a pair of constant profile, i.e. circular, gears. Fig. 8 shows part of such a transmission, the spool and input shaft being omitted and only one loop being shown. The spool is rotatable by the input shaft about the common axis of the output shaft 6 and a fixed reaction shaft 20 on which is fixed one non-circular wheel 9 of a variable-ratio gear pair, the other wheel 10 of which is fast with a side wheel 15 of a bevel differential train. Mounted on the shaft 20 is a tubular shaft 21 to which is fixed a non-circular wheel 9A in mesh with a wheel 10A fast with the other differential side wheel 17. The carrier 13 for the differential pinion 14 is connected through an overrunning clutch 19 with a circular wheel 4 in mesh with a circular wheel 5 on the output shaft 6. The gear pairs 9, 10 and 9A, 10A are similar and their phase relationship is adjustable by a thumbscrew 24 to vary the overall transmission ratio. With the wheels 9, 9A 180 degrees out of phase, as the spool carries the differential train about the axis 6, 20 the varying speeds applied to the side wheels 15, 17 cancel out in the differential train and the overall transmission ratio depends merely on the relationship between the ratio between the wheels 4, 5 and that between the wheels 9, 10 and 9A, 10A. This may be a 1 : 1 relationship resulting in zero rotation of the output shaft 6. Adjustment of the wheels 9, 9A to, e.g. a 90 degree phase relationship results in the carrier 13 varying in speed as the spool rotates such that for one quarter turn of the spool the carrier will impart rotation at constant velocity through the overrunning clutch 19 to the wheel 4, and with four similar loops equally spaced around the spool, the respective overrunning clutches 19 will take up the drive in succession to drive the output shaft continuously. The overrunning clutch may alternatively be associated with the wheel 10A. Also the arrangement may be modified such that the wheels 10, 10A are fast with the carrier 13 and the side wheel 15, respectively, and the side wheel 17 is connected with the wheel 4. Constructional forms of the transmission with three non- circular gear pairs and with hydraulic means for adjusting their phase relationship are described and illustrated. |
