초록 ▼

A pulley type speed-shifting device is provided with a driving pulley and driven pulley mounted on each transmission shaft which are parallel, and a belt member is trained between both pulleys. A moving member is connected for movement in the axial direction with one sideplate of the driving pulley

A pulley type speed-shifting device is provided with a driving pulley and driven pulley mounted on each transmission shaft which are parallel, and a belt member is trained between both pulleys. A moving member is connected for movement in the axial direction with one sideplate of the driving pulley and is axially moved on the movable sideplate through screw motion caused by relative rotation around the transmission shaft. A speed-shifting pulley mechanism is provided for rotating the moving member relatively around the transmission shaft to change the transmission ratio between the transmission shafts in accordance with a required mode change.

대표청구항 ▼

In a speed-shifting device having first transmission shaft and a second transmission shaft parallel thereto, a driving pulley and a driven pulley each of which is composed of a fixed sideplate fixedly rotatably and axially non-slidably mounted on each of said transmission shafts and a movable sidepl

In a speed-shifting device having first transmission shaft and a second transmission shaft parallel thereto, a driving pulley and a driven pulley each of which is composed of a fixed sideplate fixedly rotatably and axially non-slidably mounted on each of said transmission shafts and a movable sideplate axially slidably and fixedly rotatably mounted on each of said transmission shafts and forming a V-shaped groove with the corresponding fixed sideplate, and a belt member trained between said driving pulley and said driven pulley engaging in both V-shaped grooves whereby the transmission ratio between the transmission shafts can be changed by varying the effective radius of the engagement of each of said pulleys with said belt member by moving each said movable sideplate axially toward and away from the fixed sideplate facing thereto, the improvement comprising: a moving member fixedly axially connected to and relatively rotatably connected to said movable sideplate on said first transmission shaft and being relatively rotatably and axially movably supported on said first transmission shaft, and screw thread means connected between said moving member and said first transmission shaft for causing relative axial movement of said moving member to said first transmission shaft when said moving member is rotated at a speed different from the speed of rotation of said first transmission shaft; a speed shifting pulley mechanism adapted for adjusting the transmission ratio between said transmission shafts and having a first pulley member fixed on said moving member, a second pulley member fixedly rotatably mounted on said first transmission shaft, a third pulley member rotatably mounted for rotation around an axis parallel with said first transmission shaft and having two pulley parts, a first belt trained between said second pulley member and one of said pulley parts of said third pulley member and a second belt trained between said first pulley member and the other of said pulley parts of said third pulley member, means for changing the transmission ratio of one of said first and second belts from a normal transmission ratio to a shifted transmission ratio for transmitting the rotation of said first transmission shaft to said moving member at a shifted speed for rotating said moving member relatively around said first transmission shaft for moving the movable sideplate on said first transmission shaft relative to the fixed sideplate thereon.