Method of sensing degradation of piezoelectric actuators

摘要

Systems and methods for sensing degradation of a piezoelectric actuator in a print head. One or more electrical pulses may be transmitted to the piezoelectric actuator that cause the piezoelectric actuator to bend, thereby creating a pressure wave. The pressure wave may be sensed and converted into an electrical signal. The electrical signal may be compared to a reference signal.

主权项

1. A method for sensing degradation of piezoelectric actuators in a printer, comprising:
transmitting one or more first electrical pulses to a first piezoelectric actuator during a first time period, wherein the one or more first electrical pulses cause the first piezoelectric actuator to bend, thereby creating a first pressure wave; transmitting one or more second electrical pulses to a second piezoelectric actuator during the first time period, wherein the one or more second electrical pulses cause the second piezoelectric actuator to bend, thereby creating a second pressure wave; sensing an amplitude of the first pressure wave using the first piezoelectric actuator that created the first pressure wave; sensing an amplitude of the second pressure wave using the second piezoelectric actuator that created the second pressure wave; converting the first pressure wave to a first electrical signal with the first piezoelectric actuator; converting the second pressure wave to a second electrical signal with the second piezoelectric actuator; averaging the first and second electrical signals to produce a first averaged electrical signal; transmitting one or more third electrical pulses to the first piezoelectric actuator during a second time period that is after the first time period based upon a predetermined amount of usage of the first piezoelectric actuator, wherein the one or more third electrical pulses cause the first piezoelectric actuator to bend, thereby creating a third pressure wave; transmitting one or more fourth electrical pulses to the second piezoelectric actuator during the second time period, wherein the one or more fourth electrical pulses cause the second piezoelectric actuator to bend, thereby creating a fourth pressure wave; sensing an amplitude of the third pressure wave using the first piezoelectric actuator that created the third pressure wave; sensing an amplitude of the fourth pressure wave using the second piezoelectric actuator that created the fourth pressure wave; converting the third pressure wave to a third electrical signal with the first piezoelectric actuator; converting the fourth pressure wave to a fourth electrical signal with the second piezoelectric actuator; averaging the third and fourth electrical signals to produce a second averaged electrical signal; and comparing the first and second averaged electrical signals to identify a spectral response of a known resonance that indicates that the first piezoelectric actuator, the second piezoelectric actuator, or both is degraded or failing.