Spiral Jack/Worm Gear Spiral Lift - Types and Applications
Screw Jack / Worm Gear Screw Lift – Complete Overview
A screw jack (also known as a worm gear screw lift or螺旋丝杆升降机) is a fundamental linear actuation device that converts rotary motion into linear motion through a worm gear and screw mechanism. It is widely used across mechanical, metallurgical, construction, chemical, and medical industries for lifting, lowering, pushing, tilting, and height adjustment
How It Works
A motor or manual handwheel drives the worm shaft, which rotates the worm gear. The worm gear has
internal threads that engage with the screw (or nut), converting rotary motion into axial linear motion.
The worm gear reduction also amplifies the output force – a small input can generate a large thrust.
Key feature: Most screw jacks offer self-locking capability – loads stay in position even when power is off
Core Classification Dimensions
Screw jacks can be classified along multiple dimensions
| Classification | Types |
| By Screw Type | Trapezoidal screw (JWM) / Ball screw (JWB) |
| By Structure | Type 1 (screw moves axially) / Type 2 (nut moves) |
| By Assembly | Type A (upward) / Type B (downward) |
| By Transmission | Worm gear type / Bevel gear type |
| By Screw Head | Cylindrical / Flanged / Threaded / Flat head |
Key Specifications at a Glance
●Load Capacity: 0.5T – 120T
●Max Input Speed: 1500 r/min
●Max Lifting Speed: 2.7 m/min
●Operating Temperature: -20°C to +100°C
Related Articles
Trapezoidal Screw Jack – JWM Series
Ball Screw Jack – JWB Series
Type 1 vs Type 2 Structure