Sharp VH-25 Series Operator's Manual page 11

4、 Speed change of spindle :
By means of the variation of one set of sliding belt pulley and counter shaft gear (high or low
speed), the spindle revolution speed is changed accordingly.
a. Change of high and low speeds : (Fig 4)
Brake the spindle
Push and Turn lever (H) in either direction to the next horizontal. You can feel the "SNAP IN"
correct position through the ball-spring mechanism. If difficulty happened in meshing gears,
inching the spindle through brake lever.
Notes :
1. The spindle must be motionless completely during the speed change.
2. To shift the high speed into the low one, the spindle must be slightly turned to make it
easier for the counter shaft to engage.
3. To shift the low speed into the high one, use the brake lever so as to put a stop to the
spindle clutch. Then turn the spindle slightly so that clutch may be engaged feasibly A
" click " sound of engagement may be sensed at this moment.
b. Speed change handwheel :
Stepless speed variation between high and low speeds may controlled by means of turning
handwheel ( A ) (Fig 5). When it is turned clockwise, it is for higher speed.
Note :
1. Do not change the speed when the spindle stands still.
2. Avoid to use it when the speed is in excess of 3,000 RPM.
3. In the process of speed change from high speed to low speed, and vice-versa, do not
change the speed rapidly to safeguard the service life of the internal mechanism.
4. It takes roughly 10 to 15 second to change from low speed to the high one.
OPERATOR'S MANUAL
FIG.5
P 8 / 57