The screw jack, also known as a helical drive mechanism, is primarily used to convert rotational motion into linear motion or vice versa. There are types that mainly transmit motion, such as the feed screw of machine tool tables, and others that adjust the relative positions of parts, such as helical drive mechanisms. The screw jack consists of a worm gear reducer and a screw, with the减速部件 being a worm drive that uses the worm to rotate the worm gear for deceleration. The worm gear is akin to the nut of the lifting screw and is matched with it.
Features of screw jack:
1The working principle involves ball bearings placed between the screw thread and nut thread grooves.
2When the screw or nut rotates, the ball bearings roll along the thread raceway, creating rolling friction between the screw and nut as they move relative to each other. To prevent the ball bearings from rolling out of the raceway, return guide devices are installed at both ends of the nut's helical slots.
3They form a circulating loop with the threaded raceways, allowing the ball bearings to circulate within the nut's raceway.
The transmission type is based on the combination of relative motion between the screw and nut. There are two basic types of fundamental transmission for screw jacks.
(1)Nut fixation, screw rotation and movement; this type of transmission, due to the nut's inherent supporting role, eliminates the additional axial movement that might be caused by screw shaft bearings. The structure is relatively simple and achieves high transmission accuracy. However, the axial dimension should not be too long, as it would reduce rigidity. Therefore, it is only suitable for applications with short travel distances.
(2)The screw rotates, and the nut moves. To limit the nut's rotation in this drive type, a guiding device is required. Its features include a compact structure, good screw rigidity, and is suitable for applications with a large working stroke.
The screw jack is widely used in various industries such as machinery, metallurgy, construction, chemical industry, culture, and public health. It can accurately control and adjust the lifting or advancing height according to a certain program. It can be directly driven by an electric motor or other power sources, or operated manually.
This is a brief introduction to the knowledge of screw jack, hoping it will be helpful to you.
The screw jack mentioned above is one of our main products, featuring a compact structure, small size, light weight, wide power sources, low noise, easy installation, flexible operation, numerous functions, various accessory options, high reliability, and long service life.
