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The WIDE Type CE linear electric cylinder is available in three versions: R, S and T. The cylinder is extremely compact and “clean” in its design, since external supports are not used. Instead, the external jacket acts as the mechanical support for the cylinder. An internal sleeve in brass acts as a housing and longitudinal guide for the sliding piston to which the piston rod is keyed. The piston is fitted with a sliding ring in technopolymer (the magnetic toroidal ring is fitted to the T version only), as well as a volute which determines its movement. As the screw rotates in the volute in each of the three versions: version T with a trapezoidal shape, version S with a spherical shape, and version R with ball screw , being blocked inside the piston and guided by the technopolymer sliding ring, it is subjected to a longitudinal thrust which produces the outward or return movement of the rod to which it is keyed. The amount of thrust depends on the torque applied and the pitch of the helical screw minus the efficiency of the volute/screw system. The speed of travel depends on the speed of rotation and the pitch of the helical screw. The driven extremity of the screw is supported by a radial roller bearing and a bidirectional thrust bearing. The other extremity is supported by a roller in technopolymer which moves freely in a longitudinal direction inside the piston rod, obviously according to the movement of the screw. The hollow rod, which is ground and chromium-plated on the external surface, is guides over the entire stroke by a bushing in sintered, teflon-coated metal. The screw is rotated by an electric stepping motor, DC motor or brushless motor. The type of motor depends on the application for which the cylinder is used. In applications which do not require particularly high speeds or absolute precision, stepping motors are generally preferred for their intrinsic characteristics which make operation of the system more “economical”. Stepping motors feature the following characteristics: - high torque at low speeds. - persistence of torque when stationary. - possibility of varying the number of steps and thus the radians and fractions of radians. - possibility of feedback control using encoders. This means that, by adjusting the electronic power and control unit appropriately, intelligent movement systems can be operated with relative simplicity and economy. For movement systems in which low cost is more important than position control (ON-OFF) or high precision, a DC motor is preferable.
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