The commonly used worm gear screw jacks include the SWL series or the JWM series. They all have multiple lifting speeds to choose from. To meet various usage scenarios, of course, this is determined by the transmission ratio of the worm gear and worm.
Take HDM31 as an example:
Fast is represented by K, and the speed ratio is 6:1; Medium speed ratio is marked by ZH, and the speed ratio is 12:1; Slow is represented by M, and the speed ratio is 24:1;
The specification of the trapezoidal screw is Tr30*6, that is, the diameter of the screw is 30mm and the pitch is 6mm. Then we calculate with a 4P ordinary motor (the output speed of the four-pole motor: 1450 r/min), then the speed calculation formula of the screw jack is:
When choosing fast speed, the lifting speed: 1450 (input speed) ÷ 6 (speed ratio) × 6mm (pitch) = 1450 mm/min
When choosing medium speed, the lifting speed: 1450 (input speed) ÷ 12 (speed ratio) × 6mm (pitch) = 725 mm/min
When choosing slow speed, the lifting speed: 1450 (input speed) ÷ 24 (speed ratio) × 6mm (pitch) = 362 mm/min
Further calculation, suppose the stroke of your elevator is 500mm. Then the time required to complete the entire journey is:
When at fast speed: 500mm ÷ (1450 mm ÷ 60s) = 20.7s (seconds)
When at slow speed: 500mm ÷ (362 mm ÷ 60s) = 83s (seconds)
Note: In fact, there are not only the above three speeds. If the motor + reducer is used to drive the elevator, the input speed is the motor speed divided by the speed ratio of the reducer. If this introduction does not solve your problem, you are welcome to contact Shanghai Dianmai Transmission Technology Co., Ltd. in China.
