Method of dispensing a viscous material

A method of dispensing a viscous material on an electronic component with a dispensing system including a dispensing element, the method comprising:

• pressurizing a reservoir for holding the viscous material;
• metering a variable amount of the viscous material from the pressurized reservoir using a positive displacement pump coupled with the dispensing element and positioned outside the pressurized reservoir;
• dispensing a test amount of the viscous material from the dispensing element onto a calibrating device using the positive displacement pump;
• measuring the test amount with the calibrating device;
• producing at least one signal representative of the measured test amount;
• calculating a flow rate of the viscous material based on the at least one signal;
• adjusting the speed of movement of a positioner for moving the dispensing element relative to the electronic component based on the calculated flow rate to cause the dispensing element to dispense a desired amount of the viscous material;
• and
• dispensing the viscous material on the electronic component with the dispensing element using the positive displacement pump.

A method of dispensing a viscous material on an electronic component with a dispensing system including a dispensing element, the method comprising:

• pressurizing a reservoir for holding the viscous material;
• metering a variable amount of the viscous material from the pressurized reservoir using a positive displacement pump coupled with the dispensing element and positioned outside the pressurized reservoir, the pump having a variable pumping speed for controlling a rate of delivery of the viscous material from the dispensing element;
• dispensing a test amount of the viscous material from the dispensing element onto a calibrating device using the positive displacement pump;
• measuring the test amount with the calibrating device;
• producing at least one signal representative of the measured test amount;
• calculating a flow rate of the viscous material based on the produced signal;
• adjusting the rate of delivery of the viscous material by varying the pumping speed of the positive displacement pump based on the calculated flow rate to cause the dispensing element to dispense a desired amount of the viscous material;
• and
• dispensing the desired amount of the viscous material on the electronic component with the positive displacement pump and the dispensing element.

A method of dispensing a viscous material onto a substrate during the assembly of an electronic component and the substrate, the viscous material being heated to a first target temperature and the substrate being heated to a second target temperature, the method comprising:

• pressurizing a reservoir for holding the viscous material;
• metering a variable amount of the viscous material from the pressurized reservoir through a dispensing element connected to a positive displacement pump which is located outside the pressurized reservoir;
• measuring a first temperature representative of the temperature of the viscous material within the dispensing element using a temperature sensing element;
• comparing the measured first temperature to the first target temperature using a first closed loop control;
• measuring a second temperature representative of the temperature of the substrate using a heat sensor;
• comparing the measured second temperature to the second target temperature using a second closed loop control;
• changing the first and second measured temperatures to respectively correspond to the first and the second target temperature;
• and
• dispensing the viscous material onto the substrate using the positive displacement pump.

A method of dispensing a viscous material onto a substrate from a dispensing element carried by an X-Y-Z positioner, the method comprising:

• pressurizing a reservoir for holding the viscous material;
• metering a variable amount of the viscous material from the pressurized reservoir using a positive displacement pump coupled with the dispensing element and positioned outside the pressurized reservoir;
• dispensing a first amount of the viscous material from the dispensing element onto the substrate along a path using the positive displacement pump;
• dispensing a second amount of the viscous material from the dispensing element onto a weigh scale using the positive displacement pump;
• measuring the weight of the second amount of the viscous material with the weigh scale;
• and
• using the measured weight in a closed loop control to adjust the rate of delivery of the viscous material along the path so that the first amount of the viscous material is equal to a desired amount of the viscous material.

A method of dispensing a viscous material on an electronic component with a dispensing system including a dispensing element, a calibrating device, and a positioner, the method comprising:

• pressurizing a reservoir for holding the viscous material;
• metering a variable amount of the viscous material from the pressurized reservoir using a positive displacement pump coupled with the dispensing element and positioned outside the pressurized reservoir;
• dispensing a test amount of the viscous material from the dispensing element onto the calibrating device using the positive displacement pump;
• measuring the test amount with the calibrating device;
• producing at least one signal representative of the measured test amount;
• adjusting the speed of movement of the positioner for moving the dispensing element relative to the electronic component based on the produced signal to cause the dispensing element to dispense a desired amount of the viscous material;
• and
• dispensing the viscous material on the electronic component with the positive displacement pump and the dispensing element.