Piezoelectric Nozzle Foreign Matter Detection via Dual Driving Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid ejecting apparatuses struggle to accurately determine ejection errors caused by foreign matter attachment on the inner wall of nozzle openings, as the influence on vibration characteristics generated by the piezoelectric element is negligible.
Innovation Solution
A liquid ejecting apparatus is designed with a supply section that selectively provides a first driving signal for image formation and a second driving signal for determining foreign matter attachment on the nozzle opening. The second driving signal includes partial signals with potential changes, allowing the determination section to assess vibration generated in the piezoelectric element.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a piezoelectric element is driven by a driving signal to eject liquid from a nozzle opening, then liquid ejection and image formation are achieved, but ejection errors occur when foreign matter attaches to the inner wall of the nozzle opening due to negligible influence on vibration characteristics
Solution Approach 1:
The patent applies preliminary action by performing a determination process before normal ejection operations. A specific driving signal (second driving signal) is applied to the piezoelectric element to generate vibration, and the presence of foreign matter is determined based on this vibration characteristic before actual liquid ejection occurs. This allows detection and potential correction of nozzle blockages before they affect image quality.
Solution Approach 2:
The patent utilizes mechanical vibration by driving the piezoelectric element with a specific driving signal to generate vibration in the ejecting section. The vibration characteristics (frequency, amplitude) are measured and analyzed to detect foreign matter attachment on the nozzle opening inner wall. When foreign matter is detected, the system can take corrective actions such as increasing driving frequency or amplitude to dislodge the foreign matter.
2Device complexity
If a single driving signal is used for both image formation and foreign matter detection, then device complexity is reduced, but the ability to accurately detect foreign matter attachment is compromised
Solution Approach 1:
The patent applies universality by making the piezoelectric element serve multiple functions: it acts as both the actuator for liquid ejection during normal operation and the sensor for foreign matter detection during the determination process. The same piezoelectric element is driven by different driving signals (first for ejection, second for detection) to achieve both functions without adding separate detection sensors or actuators.
Solution Approach 2:
The patent utilizes parameter changes by varying the driving signal parameters (frequency, amplitude, waveform) depending on the operation mode. For normal ejection, a first driving signal with specific parameters is used. For foreign matter detection, a second driving signal with different parameters is applied to generate measurable vibration. This allows the system to optimize performance for each function while using the same hardware.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables accurate detection of ejection errors due to foreign matter attachment, improving image quality by effectively identifying and addressing nozzle clogging issues.
Implementation Method 1
a piezoelectric element disposed on the ejecting section included in the liquid ejecting apparatus by a driving signal
Data Source
AI summary
A liquid ejecting apparatus includes a supply section configured to selectively supply a first driving signal that drives a piezoelectric element to form an image or a second driving signal that drives the piezoelectric element to determine whether a foreign matter adheres to an inner wall of a nozzle opening, and a determination section that determines whether a foreign matter adheres to the inner wall. The second driving signal includes a first partial signal having its potential changed from a first potential to a second potential, and a second partial signal having its potential changed from the second potential to the first potential. The determination section determines, after the first partial signal is supplied to the piezoelectric element, based on vibration generated in the piezoelectric element due to supply of the second partial signal, whether a foreign matter adheres to the inner wall.