Belt-pulley type steplessly variable transmission having a reverse drive gear mechanism

Claim 2

A steplessly variable power transmission mechanism comprising an input member, a belt-pulley type transmission having an input shaft for carrying driving pulley means of a variable effective diameter, an output shaft for carrying driven pulley means of variable effective diameter and belt means for connecting the driving and driven pulley means so that power can be transmitted between the driving and driven pulley means, reverse gear means provided with a first idler shaft having an idler gear means for engaging with said input member and a second idler shaft having an intermediate gear means in engagement with the idler gear means of the first idler shaft, said first and second idler shafts being disposed in parallel with said input member, output means connected with said output shaft of the belt-pulley type transmission and said reverse gear means, first selecting means provided on said input member for connecting said input member with said input shaft of the belt-pulley type transmission, second selecting means provided on said first idler shaft for connecting said intermediate gear means of the second idler shaft with said idler gear means of the first idler shaft, said first and second selecting means being located within substantially the same plane perpendicular to the longitudinal direction of the input member, said first and second selecting means being adapted to be actuated alternately to the respective engaged positions thereof, whereby driving power is transmitted from said input member through said reverse gear means to said output means in bypassing the belt-pulley type transmission when the reverse gear means is actuated.

Claim 3

A power transmission mechanism in accordance with claim 1 which is applied to a vehicle drive system and in which said belt-pulley type transmission includes hydraulic means for determining the effective diameters of said driving and driven pulley means, said output means including a differential gear mechanism.

Claim 4

A power transmission mechanism in accordance with claim 1 in which said input member includes a driving gear which is engaged with said idler gear on the second counter shaft.

Claim 5

A power transmission mechanism in accordance with claim 1 in which said first and second selecting devices respectively include synchronizer mechanisms.

Claim 6

A power transmission mechanism in accordance with claim 1 which includes a first output gear mechanism between said driven pulley means of the belt-pulley type transmission and said output means.

Claim 7

A power transmission mechanism in accordance with claim 5 in which said first output gear mechanism includes a first counter shaft having a first output gear engaged with said driven pulley means and said output means.

Claim 8

A power transmission mechanism in accordance with claim 6 in which said reverse gear means includes a second counter shaft having an idler gear engaged with a driving gear provided on the input member and a third counter shaft having an intermediate gear engaged with said idler gear and a second output gear engaged with said output means.

Claim 9

A steplessely variable power transmission mechanism comprising a belt-pulley type transmission having an input shaft carrying driving pulley means of a variable effective diameter, an output shaft carrying driven pulley means of a variable effective diameter and belt means connecting the driving and driven pulley means so that power can be transmitted between the driving and driven pulley means, a power clutch for controlling transmission of driving power from an engine, a first counter shaft in parallel with the output shaft, a first output gear provided on the first counter shaft to thereby connect the output shaft with a final gear, an input member disengageably connected to the input shaft for transmitting the driving power, gear means provided with a first idler shaft having an idler gear means for engaging with said input member and a second idler shaft having an intermediate gear means in engagement with the idler gear means of the first idler shaft, said first and second idler shafts being disposed in parallel with said input member, a second output gear provided on the first counter shaft and connected to the final gear, a selecting means provided with first selecting means and second selecting means for selecting one of two power transmitting mechanisms, said first selecting means provided on said input member for connecting said input member with said input shaft of the belt-pulley type transmission, said second selecting means provided on said first idler shaft for connecting said intermediate gear means of said second idler shaft with said idler gear means of said first idler shaft, said first and second selecting means being located within substantially the same plane perpendicular to the longitudinal direction of the input member, said first and second selecting means being adapted to be actuated alternately to the respective engaged positions thereof, wherein a first power transmitting mechanism is adapted to transmit the power from the input member to the input shaft and a second power transmitting mechanism is adapted to transmit the power from the input member to the second output gear of the second counter shaft through said gear means.

Claim 10

A steplessely variable power transmission mechanism comprising a belt-pulley type transmission having an input shaft carrying driving pulley means of a variable effective diameter, an output shaft carrying driven pulley means of a variable effective diameter and belt means connecting the driving and driven pulley means so that power can be transmitted between the driving and driven pulley means, a power clutch for controlling transmission of driving power from an engine, a first counter shaft in parallel with the output shaft, a first output gear provided on the first counter shaft to thereby connect the output shaft with a final gear, an input member disengageably connected to the input shaft for transmitting the driving power, gear means provided with a first idler shaft having an idler gear means for engaging with said input member and a second idler shaft having an intermediate gear means in engagement with the idler gear means of the first idler shaft, said first and second idler shafts being disposed in parallel with said input member, a second output gear provided on the first counter shaft and connected to the final gear, a selecting means provided with first selecting means and second selecting means for selecting one of two power transmitting mechanisms, said first selecting means provided on said input member for connecting said input member with said input shaft of the belt-pulley type transmission, said second selecting means provided on said first idler shaft for connecting said intermediate gear means of said second idler shaft with said idler gear means of said first idler shaft, said first and second selecting means being located within substantially the same plane perpendicular to the longitudinal direction of the input member, said first and second selecting means being adapted to be actuated alternately to the respective engaged positions thereof, wherein a first power transmitting mechanism is adapted to transmit the power from the input member to the input shaft and a second power transmitting mechanism is adapted to transmit the power from the input member to the second output gear of the second counter shaft through said gear means.

Claim 11

A steplessly variable power transmission mechanism comprising an input member, a belt-pulley type transmission having an input shaft carrying driving pulley means of a variable effective diameter, an output shaft carrying driven pulley means of a variable effective diameter and belt means connecting the driving and driven pulley means so that power can be transmitted between the driving and driven pulley means, reverse gear means provided with a first idler shaft having an idler gear means for engaging with said input member and a second idler shaft having an intermediate gear means in engagement with the idler gear means of the first idler shaft, said first and second idler shafts being disposed in parallel with said input member, said reverse gear means being independent of said input shaft and engageable with said input member, output means connected with said output shaft of the belt-pulley type transmission and said reverse gear means, selecting means provided with first selecting means and second selecting means for connecting said input member selectively with one of said input shaft of the belt-pulley type transmission and said reverse gear means, said first selecting means provided on said input member for connecting said input member with said input shaft of the belt-pulley type transmission, said second selecting means provided on said second idler shaft for connecting an intermediate gear means of the second idler shaft with said idler gear means of the first idler shaft, said first and second selecting means being located within substantially the same plane perpendicular to the longitudinal direction of the input member, said first and second selecting means being adapted to be actuated alternately to the respective engaged positions thereof, whereby driving power is transmitted from said input member to said output means through said belt-pulley type transmission to drive said output means in a first direction of rotation and to said output means through said reverse gear means to drive said output means in an opposite direction of rotation without subjecting said belt means to a high tensile load.

Claim 12

A steplessly variable power transmission mechanism comprising an input member, a belt-pulley type transmission having an input shaft carrying driving pulley means of a variable effective diameter, an output shaft carrying driven pulley means of a variable effective diameter and belt means connecting the driving and driven pulley means so that power can be transmitted between the driving and driven pulley means, reverse gear means provided with a first idler shaft having an idler gear means for engaging with said input member and a second idler shaft having an intermediate gear means in engagement with the idler gear means of the first idler shaft, said first and second idler shafts being disposed in parallel with said input member, said reverse gear means being independent of said input shaft and engageable with said input member, output means connected with said output shaft of the belt-pulley type transmission and said reverse gear means, selecting means provided with first selecting means and second selecting means for connecting said input member selectively with one of said input shaft of the belt-pulley type transmission and said reverse gear means, said first selecting means provided on said input member for connecting said input member with said input shaft of the belt-pulley type transmission, said second selecting means provided on said second idler shaft for connecting an intermediate gear means of the second idler shaft with said idler gear means of the first idler shaft, said first and second selecting means being located within substantially the same plane perpendicular to the longitudinal direction of the input member, said first and second selecting means being adapted to be actuated alternately to the respective engaged positions thereof, whereby driving power is transmitted from said input member to said output means through said belt-pulley type transmission to drive said output means in a first direction of rotation and to said output means through said reverse gear means to drive said output means in an opposite direction of rotation without subjecting said belt means to a high tensile load.