This application rejects bottles or cans from a filling line.
The level of liquid in the bottle determines if it is accepted or rejected. This is sensed as the bottle passes through an inspection process upstream from the actuator station. If it fails this test a signal is given to the SMAC controller to perform a cycle. There is a delay between the bottle being sensed and the signal being given, which is controlled by a PLC on the line.
There are two routines programmed into the unit. The first (program “A”) is a two-stage move consisting of a slow move out to an interrupt position, followed by a fast out and retract move. The second (program “B”) is a simple out and retract, for high speed applications. There are three “A” profiles set in the controller and one “B” profile, along with an edit routine for each. The three different “A” profiles are selected using input channels, the program has to be stopped and MS240 typed to run profile “B.” There are a number of registers used to store the three positions (start, interrupt, final) and two accelerations (initial, final). Editing is done through an OMRON PLC using the RS232. All setup is by touch screen via RS232 to the controller. The operator sets the profile needed. The LAL90-50 actuator and LAC1 controller sit inside a stainless steel box. This is necessary as the unit will be in an environment that will be washed down regularly. The rod exits the box through a 10mm wiper seal. The cable from the actuator will have the 25-pin D-type connector replaced by a 15-pin connector and will plug directly into the controller.
The SMAC system improves upon the previous method because: – The previous system was pneumatic, and if the cylinder did not reject any bottles for several hours and then had to reject one, static friction in the seals would cause the first cycle to be slow and ejector could be hit by the next bottle in the line. – The profile can be changed for different bottle shapes. Slow approach then high speed means bottles do not fall over, an important factor for high-cost liquid bottling. This could not be done with the previous system. – Out and back movements in 50ms means the actuator is suitable for lines up to 1,200 bottles per minute, good for filling glass bottles. (Cans run about 2,200 per minute and are usually split into two inspection lines of 1,100 per minute each.)