IAI shows the advantages of modern electric cylinders over pneumatic drives with the "Robo Cylinder" series of products: They are not prone to load fluctuations, enable smooth starting and stopping, simple speed regulation and the control of various positions with the highest repeat accuracy.
Also for cost and environmental reasons, electric cylinders have become indispensable in modern, sustainable production. You save energy and at the same time contribute to a "green" image for the manufacturing companies.
The company has determined and compared the energy consumption for a compressed air cylinder and a parallel electric cylinder (Robo Cylinder). The comparison took place under identical conditions with the same parameters: pressure hold time, energy cost per unit, unit cost of air, speed, payload, stroke length, ambient temperature and operating time. The costs were calculated on the basis of an industrial electricity price of 0,1 Euro per kWh under the condition of an uninterrupted operation and a powerful compressor. It turned out that even small leaks can cause considerable costs. A leakage hole of one-sixteenth of an inch (1,6 mm) causes an annual extra cost of 688 Euro, a double the leakage (3,2 mm) already 2750 Euro, while a hole of only ¼ inch (6,4 mm) makes a company even the proud amount from 11.000 Euro per year.
Even without a visible hole, leakages - even if they are only as big as a pinprick - generally speed up the energy bill. These leaks can be a cause of energy waste in an industrial compressed air system that should not be underestimated; in some cases, the loss may be up to 20 to 30% of compressor power. As leaks reduce air pressure in the plant, pneumatically powered machines are less economical - manufacturing costs often increase dramatically.
Problem solving: Electric cylinders
With electric cylinders, these expensive losses can be a thing of the past. The electric cylinders are characterized by an easy-to-use software and offer all the advantages of a high-quality electrical axis. Their effective efficiency reaches 80 to 90%, while the typical overall efficiency of a pneumatic system is only about 10%.
As the cycle frequency increases, the power requirements of a pneumatic cylinder increase linearly, while the power consumption of the energy-efficient RoboCylinders remains constant. Thus, the difference in energy consumption with the number of work cycles per minute is getting bigger. When both cylinders are operating at 10 cycles per minute, a Robo Cylinder only consumes 1 / 3 of the power of the pneumatic cylinder. If both cylinders work with 30 cycles per minute, this difference becomes even clearer: The Robo Cylinder requires only one tenth of the energy of the pneumatic cylinder. Thus, electric cylinders represent a rapidly amortizing investment with comparatively high savings potential.
But also in terms of precision and programmable options, electric cylinders are clearly in the lead, as some examples show: The RoboCylinders enable multi-point positioning of 500-different positions with a high repeat accuracy of ± 0,02 mm. Thus, with only a single production line a variety of different products can be produced.
The force (thrust) exerted by the electric cylinders can be precisely controlled by simply adjusting the position values. In this way a constant pressure is possible. This feature is interesting for pushing, clamping, detecting, press-mounting or clamping workpieces - resulting in higher production quality.
Both speed and acceleration and deceleration of the RoboCylinders can be programmed exactly for each position. This improves cycle times, can dramatically reduce workpiece damage, and improve product quality.
Meaningful warning signal
If the Robo Cylinder reaches a specific, pre-set section, an outgoing signal can be generated automatically without additional sensors. The output of such a (warning) signal can be useful and necessary for a wide variety of applications. As no additional sensors are required, this saves additional investment in sensor technology and in its maintenance and operation.
Unlike pneumatic systems, Robo Cylinders can stop a slide at any point and decelerate until it stops when receiving an external signal during operation. So z. B. collisions are avoided.
In the fixed-path continuous method, repetitive motion is possible based on the data of a single position. Working with a single position data set without entering many individual positions significantly simplifies the programming effort. A desired, fixed distance can be so quickly entered into a position data table.
The RoboCylinders of the DC stepper motor series ERC2 / RCP2 stop immediately and do not generate micro vibrations, as in conventional AC servomotor drives. Therefore, they are suitable, for example, for measuring systems with cameras.