Which Screw Jacks Require a Brake Motor, Ball Screw Jacks Are Self-Lowering. Brakes Are for Use on Any Jacks If Vibration Is Present. Any jack that will lower under load requires a brake motor. This includes ball screw jacks, ball screw electric cylinders and bevel gear jack with ball screws. Machine screw jacks with double lead screws jacks may also require brakes to hold postion. Worm gear machine screw jacks lift and precisely position loads (500 pounds to 100 tons). Upright or inverted jacks operate at full capacity in tension or compression. single lead jacks are self-locking. double lead jacks offer increased travel speed and require a brake or external locking device to hold position. Machine screw jacks are used in countless applications. They are frequently used in steel machinery, packaging machinery, food processing machinery, and in wash down applications. Choose a Ball screw jack if you have a higher duty cycle, faster travel speed, and do not require a self-locking screw. Ball screw jacks are inherently more efficient, requiring 1/3 the horsepower compared to trapezoidal worm gear jacks. Due to the efficiency of a ball screw jack, a brake must be used to stop and hold a load in position. Brakes are also recommendefor use on any jacks if vibration is present.
Machine Screw Jacks having gear ratios between 20:1 and 32:1, are self-locking and, in the absence of vibration, will hold loads without backdriving. All other ratios may require a brake to prevent backdriving. All Ball Screw Jacks can backdrive and require some means of holding the load, such as a brake on the motor. The product specification pages show holding torque values. Holding torque represents the amount of input torque required to restrain the load.
Which Screw Jacks Require a Brake Motor, Ball Screw Jacks Are Self-Lowering. Brakes Are for Use on Any Jacks If Vibration Is Present.