ADHESIVE DISPENSING DEVICE HAVING OPTIMIZED RESERVOIR AND CAPACITIVE LEVEL SENSOR

摘要

PROBLEM TO BE SOLVED: To improve an adhesive dispenser device and a level sensor for use with different types of hoppers and different types of filling processes.SOLUTION: An adhesive dispensing device 10 includes a heater unit 20 for melting adhesive, a fill system communicating with a receiving space 16 for feeding the heater unit, and a reservoir 22 for receiving melted adhesive from the heater unit. The dispensing device also includes a capacitive level sensor 18 located along a sidewall of the receiving space such that the level of adhesive in the receiving space can be detected by sensing the difference in dielectric capacitance where the adhesive is located compared to where air acts as the dielectric. The size of the driven electrode 100 produces a broader sensing window capable of generating multiple control signals corresponding to different fill levels of adhesive. The receiving space and the reservoir are minimized in size so that adhesive is not held at elevated temperatures long enough to char or degrade.