No one knows for sure when and where glass was first manufactured. Around 2600 BC, glass already appeared in Mesopotamia and Egypt. Nowadays, glass has been widely applied in automobile windshield window, building curtain wall, store showcase, bathroom door and window and so on. The glass has to go through the tempering process to make sure the strength and toughness suitable for application before put into use. The glass has to go through edge grinding process before tempering process, otherwise, glass edge breakage and burst may occur in the glass tempering furnace. So the edge grinding process is very important. Based on the products advantages, Kinco has provided a solution based on CANopen for the glass 4-edge grinding procedure.
Main technology of glass 4-edge grinding process
System control structure
The control logistic is realized by CoDesys platform. CoDesys fully supports modularization programming. The program modules are independent as well as correlated with each other. Then the programmer could get rid of the limitations of linearization programming. In this solution, the system control structure is as follows:
System control difficulties
Key points of system control:
1）The system should self adapt length of glass instead of inputting length and width manually.
2）The left and right edges are grinded during glass moving. When glass spans two different conveyors, the speed of two conveyors should be synchronous.
3）When rising edge is detected by the detecting switch installed on grinding head, the current position of servo should be caught immediately. At the same time, servo motor moves a fixed distance. The glass is moved at a speed of 20m/s, which requires motor speed up to 2000rpm. Under this condition, actual position should be caught by rising edge and servo moves a very short distance, which requires response speed of the system should be fast enough.
4）Servo should switch among speed/position/synchronous modes freely with no stop and vibration.
Kinco CANopen solution
Concerning the above referred difficulties, Kinco provides solutions based on CANOpen. Combining the fast pulse position catch function of Kinco servo, controller sends commands via CANOpen communication to each axis of the bus to realize dynamic mode switching. The system configuration structure is as follows:
Advantages of Kinco solution
1）CANopen solution is adopted to control servo instead of controlling servo via pulses from PLC. The wirings are simplified, as well as inaccurate positioning caused by disturbed pulse signal can be avoided.
2）Fast pulse position catch function is embedded in servo firmware. PLCs do not participate in position signal catch. So there is no need to configure high speed counter or high speed counter interrupt in PLC program. PLC only concerns on logical control. Therefore the PLC program is simplified.
3）The system is characterized of high expansibility. It is very convenient for system update or increasing control axis. Users only need to add new axis to the bus directly. F1 controller is integrated with Ethernet port to connect with enterprise ERP system, which helps to improve factory informationization.