Abstract:
A system for dispensing material on a substrate includes a dispensing unit having a dispensing piston. The dispensing piston is pneumatically driven from a first lower position to a second upper position. The system further includes a solenoid valve coupled to the dispensing unit, with the solenoid valve being configured to control air flow to and from the dispensing piston. The solenoid valve includes a solenoid coil and an amplifier connected to the solenoid coil. The system further includes a controller coupled to the amplifier, with the controller being configured to generate a command signal to the amplifier to control current in the solenoid coil.
Abstract:
A dispenser, configured to dispense material on a substrate, includes a dispensing unit having a housing with a chamber, a piston disposed in the chamber and axially movable within the chamber, and a nozzle coupled to the housing. The nozzle has an orifice co-axial with the chamber of the housing. The dispenser further includes an actuator coupled to the dispensing unit and configured to drive the up- and down movement of the piston, and a compliant assembly coupled to the actuator and the piston. The compliant assembly is configured to permit limited relative travel between the actuator and the piston. A method of dispensing is further disclosed.