Casings are made of two identical polymer half-shells. The two halves are connected by means of screws and nuts.
Even for the Aleph series worm screws are made of a special steel 16NiCr4 (according to the UNI EN
10084:2000 requirements). They undergo thermal treatments like case-hardening and carburizing
before being thoroughly ground on both the threads and the tangs. Worm screws are available in three different reduction ratios: 1/5, 1/10, /30.
The worm wheels and support nuts (lead nuts) are COMPLETELY made of polymer. This is very important because, obtaining the trapezoidal threading by moulding, it is possible to keep the fibers integrity, ensuring better mechanical features. The trapezoidal threading geometry meets the requirements of the ISO 2901:1993 norm. The only machining is carried out for the worm wheel toothing; in this way it is possible to supply the three different ratios highlighted in the previous paragraph.
The 20x4 and 30x6 threaded spindles reflect the same characteristics listed in the respective paragraphs for the trapezoidal screw jack chapter. They are mainly manufactured by rolling carbon steel C 45 grounded bars (according to the UNI EN 10083-2:1998). The trapezoidal threading geometry meets the requirements of the ISO 2901:1993 norm. Threaded spindles made of AISI 316 stainless steel or other materials can be manufactured upon request.
New market demands, the growth of light applications and a spirit of innovation and research
have pushed UNIMEC to realize a new trapezoidal screw jack series, the Aleph series.
This new line includes two sizes and its peculiarity is that some components are made of a
techno-polymer having very high mechanical features. Having a structure quite similar to full metal screw jacks, Aleph series screw jacks have the same load handling functions and they also maintain the same IRREVERSIBILITY features.
The particular moulding system of the gears and the peculiarity of the polyacrylamide material
employed, allow it to operate even without lubrication.
Aleph screw jacks can work singularly or in groups connected by means of joints, shafts and
bevel gearboxes. At present, a direct motorization with flange is not possible.