Pneumatics are very similar to electronics. Instead of electricity flowing, compressed air flows – accomplishing the same basic result.
Referring to the circuit diagram, the operation of the BioJector IV / IV-2 is as follows:
Compressed air enters the machine at the coupler and goes through a combination filter and regulator which maintains the desired operating pressure provided the machine is being supplied with at least 5 bar (70 PSI) line pressure. The filter is a 20 micron mesh which prevents harmful airborne particles from entering the pneumatic system, with a drain feature that allows for removal of condensed moisture from the compressed air line. Air leaves the filter regulator and goes to the main on/off switch and to the counter reset valve. When the on/off switch is in the “on” position, air is supplied to the counter, the micro valve and the pilot valve which feeds the actuator valve. When the micro valve pushbutton is pressed, air is fed to the actuator which produces a motion of the plunger of .2 seconds regardless of how long air is fed to it. The output of the actuator valve goes directly to the power cylinder and to the counters. Each time the micro valve is pressed, the power cylinder will move forward and return automatically; the ascending counter will increase by one and the descending counter will decrease by one. When the descending (batch) counter reaches zero, it sends a signal to the pilot valve which disconnects the air supply to the actuator valve, preventing any more vaccinations until the batch counter is reset. At the same time, the counter sends a signal to the whistle giving an audible indication of the end of a batch.
A third position on the on/off switch is the manual (test) position. With the on/off switch in the “manual” position, air is fed directly to the power cylinder, holding it extended until the switch is moved to “off” or “on”. The manual position is used to adjust the needle position.
Please note: After each injection a tiny drop collects on the needle. This is normal and no reason for a complaint.
