ELECTRIC CYLINDERS AND PRESSES Series SA

The electromechanical system Stroke, speed, force, precision and life cycle are the most important characteristics of the system The cylinder consists basically of a motor and a spindle screw, with a nut running along it. Our spindle screw uses planetary roller technology (the finest at the state of the art) housed inside a sturdy tubular structure. The motor is controlled by a servo drive, controlled by electronics designed and built in house.

The benefits of the system Being a press and not just a linear actuator, there are built-in sensors that enable the complete and accurate control of the pressing operations. The physical dimensions controlled are force and position, The force is measured by a load cell and the position is detected by an absolute encoder. SA presses are used where it is necessary to control the production process in real time for all pieces manufactured, in order to ensure that there are zero defects. • Clean Requires no pneumatic and/or hydraulic powering. • Active control of the process The movements are constantly...

The command and control chain The synergy between servo-drive and electronics is essential. Tool Press-Right The control system has been designed specifically for pressing operations and employs all the experience of Alfamatic in this sector, dating back to 1992. Software WinScope® For machine manufacturers, Alfamatic supplies an installation kit complete with press structure and electrical cabinet. See page 19 Alfamatic also offers a series of complete and certified pressing stations in a variety of configurations (with a c-frame structure, with a two or fourcolumn structure, with an electromechanical...

Load cell Servo drive Communication line Temperature sensor Movement command Absolute Encoder Motor power cable It controls the force and instantaneous position of the cylinder in real time. It shows the working curve and checks that it stays within pre-set parameters Servo drive It drives the brushless motor of the cylinder and controls the position of the piston-rod. The standard version of the system is in safety category 4. This is made possible by the interruption, at every cycle, of the power supply to the servo drive. This guarantees maximum safety in pressing applications. A planetary...

Transmission group Made up of drive and conduct pulleys, connected by an inclined teeth belt. The fine pitch of the roller screw allows the assembly without speed reducer, benefiting reliability, noise and performance. The special inclined teeth belt guarantees: • silence • low vibrations Brushless motor with absolute encoder The best solution for: • torque curves • no maintenance • dimension-to-power ratio The absolute encoder keeps the cylinder position constantly in the memory (NO zero search): the cylinder is immediately ready to go. Planetary roller screw Load cell built-into the actuator...

Press-Right is a measurement system that provides 100% quality control on the manufacturing process. Interfaced to a position transducer and a force transducer, it continuously monitors the position/force curve and verifies that it stays within a specifically positioned continuous control range. The system architecture is based on a multiprocessor for data monitoring and analysis and is connected directly to the sensors. The instrument actively controls the movement of the motor, promptly controlling the force and position values. D Rear panel A - USB connection B - Ethernet connection C - SD memory...

The SA system regulates the cylinder speed in real time, using the force and position transducers for feedback. Production management and control The continuous regulation of the speed with feedback from the force transducer makes it possible to reach the required force in the best way: the speed is reduced only when the force measured during pressing approaches the required value. This reduces the cycle time and the real force applied does not significantly exceed that required. Stopping value reached The SA system architecture also makes it possible to maintain the force constant for a specific...

Management of the cylinder stopping point When a determined force and/or stroke value is reached, the stop and return of the press are commanded. Pressing interference control During the entire pressing operation, the interference between the two pieces to be assembled is checked. Control band The continuous band system guarantees control of every point of the press curve. This prevents all the uncertainties deriving from the use of discreet windows which leave some areas uncontrolled. The bundled software also allows the automatic creation of the band, based on sample curves. Geometric check...

Check of presence and correct positioning of the piece correctly positioned piece incorrectly positioned piece piece not inserted in the relative housing Example of positioning and relative press curves Non-destructive measurement For large and expensive parts. The cycle stops whenever the monitoring curve goes outside the tolerance band. As the check takes place in real time, it preserves the integrity of the piece. Check on elastic elements From the curve measured, it is possible to determine the correspondence of the elastic element with the project specifications. Determining fracture values...

Stopping and holding the programmed force value Checking the contact point Thanks to the feedback of the closed loop force value, the force is held constant, automatically and continually correcting the cylinder position. Correcting the structure deformation The instrument continuously calculates the real position of the cylinder, taking into account the deformation of the loaded structure. Relative position The working parameters can be automatically set referring to the contract point between the tool and the piece, regardless of the dimensional tolerances. Using a micrometric probe, this possibility...

WinScope® software Programming The SA with Press-Right is a stand-alone system and does not require the use of a computer. The programming and control functions are performed by the instrument in a clear and simple way. However, the occasional or continuing use of a computer connected to the instrument can add some functions to the system. The WinScope® programme is supplied for this purpose. Central management WinScope®, it is possible to simultaneously monitor, control, programming and archiving of the data of several presses from a single computer. WinScope® makes the programming of the tool...