The working principle of the hand operated worm gear screw jack is that the worm (also called the input shaft) is manually rotated by the hand wheel, the worm wheel is rotated by the worm, and the trapezoidal lifting screw is moved by the rotating worm wheel. The linear motion speed of the worm wheel manual screw jack trapezoidal lifting screw depends on the thread size and the worm gear speed ratio.
Hand Operated Screw Jack is composed of hand wheel or hand crank and a worm gear screw jack.It is ideal solutions for applications where electricity or power generators is inconvenient or dangerous.
Our Jack's Advantages:
-Self-locking ability
-Can be driven directly by hand wheel
-Can be customized according user's demand
-Compact configuration, small size, lightweight
-Convenient installation, flexible operation
-High reliability and stability
-2 / 3 /4 /8 sets etc. screw jacks to linkage to use
Please see a short video about hand operated screw jack for crank table below,