What is the working principle of the single tube precision screw valve glue supply series
source:
m.8678g.com | Release time:2026年05月07日
The core principle of single tube precision screw valve (single component) is volumetric metering+screw stator sealing chamber pushing+servo closed-loop control. It is driven by a motor to rotate the screw, and the glue is squeezed out of the nozzle in a "quantitative, constant speed, and pulsation free" manner. It stops when stopped and reverses to suck back and prevent dripping and leakage.
1、 Core structure (three major components)
Servo motor+coupling: provides correct torque and angle control, can rotate forward/reverse/speed regulation.
Screw (rotor)+stator: core measuring pair, eccentric spiral fit, forming a continuous sealed cavity when rotating.
Feed inlet+valve chamber+nozzle: glue inlet, stabilizing chamber, glue outlet; When the screw does not rotate, it is self-locking by the sealing chamber and does not release glue even when pressurized.
2、 Work process (four step cycle)
Standby: Motor stopped, screw stationary; The glue is self-locking with the sealing chamber due to its viscosity, without dripping or drawing.
Glue supply/feeding: The pressure of the material cylinder (0.2-0.5MPa) presses the glue into the feeding port and into the gap between the screw and the stator.
Measurement push (core): The servo motor drives the screw to rotate eccentrically. With each revolution, the sealing chamber volume is fixed, and the glue is pushed to the outlet at a uniform speed in the axial direction without pulsation; Glue output=speed x time x single cycle displacement, with an accuracy of within ± 1%.
Glue breakage/suction back: When stopped, the motor quickly reverses at a small angle to pull back the glue at the nozzle, preventing wire drawing and dripping.
3、 Key principles and key points
Volumetric quantification: does not rely on air pressure to control flow rate, but on the rotation speed of the screw to determine the amount of glue, which is not affected by changes in glue viscosity or liquid level, and has good consistency in dispensing.
Low shear conveying: The screw push is a volumetric translation, which has minimal shear on the adhesive, does not damage the components (such as conductive adhesive and UV adhesive), has no bubbles, and does not cure.
Self sealing self-locking: The screw and stator are interference fit, and the sealing chamber automatically seals when rotating; Stop at rest without the need for additional valve sealing.