Instead of the worm drive systems discussed here, a bevel gear system could be used to convert rotation to linear movement. This might offer greater performance to a machine screw jack due to it making a rolling contact as opposed to the sliding contact of worm drive parts. It could, however, come at a larger initial cost and does not cover as higher ratio range as worm drives.
Also known as power screws, lead screws include several different types of thread profile which are suitable for different applications. Acme lead screws are defined by their trapezoidal thread profile and 29° flank position and are commonly found in American Imperial machine screw jacks. An alternative solution to the Acme lead screw in a machine screw jack would be a square lead screw.
European or other international screw jacks utilise a trapezoidal lead screw with a 30° flank position and complies to an ISO metric standard.
Ball screw jacks require the thread of the lead screw to possess a profile which allows for the travel of the balls. To enhance load distribution and minimise put on, the ball screw track includes a gothic arch profile.
Recognition of the trapezoidal screw thread originates from the fact that it is easier to machine and is therefore less expensive than square and ball screw thread forms. Additionally, due to the large area of contact between your lead screw threads and the worm wheel, there is usually a large load carrying capability. This outcomes in high friction which is certainly detrimental to efficiency but does mean the system is much more likely to end up being self-locking. This low efficiency implies that such screw jacks are more suitable for noncontinuous or intermittent operation.

Many applications do not warrant the excess expenditure of a ball screw jack since they usually do not require continual drive. In configuring a screw jack a prediction is made of the frequency of actuation and this will stage to the correct screw jack to become selected.

Translating Design Jacks ‘re normally selected. With this style, a driven input worm works on an interior worm gear leading to the lifting screw to extend or retract. Operation needs that rotation of the lifting screw end up being avoided. This rotation it restrained whenever two or more jacks are linked with the same load.
Keyed Design Jacks are utilized any moment rotation of the lifting screw is not restrained. For example, when you need to lift the jack to meet up a load. This is how they work: An integral, set to the jack casing and inserted into a keyway milled in to the length of the lifting screw forces the lifting screw to translate without rotating.
Keyed For Travelign Nut Style Jacks (KFTN) are another option. These jacks have a fixed size lifting screw that rotates. Loads are mounted on a flanged “journeying” nut that translates along the length of the rotating screw. This type of jack is perfect for applications that cannot support a screw safety tube or that require a flush mount
The worm wheel acts on the ball screw (via the ball nut) which actuates the lead screw. This technique offers greater efficiency between the insight and the useful result compared with a machine screw jack. Furthermore, it allows for greater actuation speeds and, due to the low friction, is very durable. However a ball screw jack isn’t inherently self-locking and, because of its improved precision components, the initial outlay is better. The resulting improved performance however implies this can be offset against smaller drive train components and a significant decrease in the necessary power.