Piezo Inkjet Nozzle Viscosity Control Without Heater
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid ejecting apparatuses, such as ink jet type recording devices, face challenges in maintaining desired ejection characteristics when operating in low temperature environments due to increased liquid viscosity, leading to complex structures and size limitations when heaters are used for heating.
Innovation Solution
A liquid ejecting apparatus incorporating a piezoelectric actuator that generates non-ejection and ejection vibration pulses to manage liquid temperature without the need for a heater, using a control system to select and supply appropriate drive waveforms based on temperature detection, ensuring stable ejection characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a heater is provided in the ejection section for heating the liquid, then the liquid viscosity is reduced and ejection characteristics are improved, but the structure of the liquid ejecting apparatus becomes complicated and size reduction becomes difficult
Solution Approach 1:
The patent replaces the thermal heating system (heater) with a mechanical vibration system (piezoelectric actuator). The piezoelectric actuator generates vibration pulses that agitate the liquid, reducing viscosity through mechanical energy input rather than thermal energy. This substitution eliminates the heater component and associated thermal management structures, thereby simplifying the device structure while maintaining the ability to control liquid viscosity for optimal ejection characteristics.
Solution Approach 2:
The patent changes the method of energy input to the liquid from thermal parameters (temperature increase via heater) to mechanical parameters (vibration frequency and amplitude via piezoelectric actuator). By controlling the vibration pulse parameters, the system achieves viscosity reduction and ejection control without the need for thermal heating infrastructure, thus reducing structural complexity.
2Reliability
If a heater is provided in the ejection section for heating the liquid, then the liquid viscosity is reduced and ejection characteristics are improved, but the space for disposing the heater is required and size reduction is difficult
Solution Approach 1:
The piezoelectric actuator serves dual functions: it acts as both the ejection actuator and the heating mechanism through vibration-induced liquid agitation. This eliminates the need for a separate heater component and its associated space requirements. The vibration pulses generated by the piezoelectric actuator directly reduce liquid viscosity without requiring additional thermal management components, thereby reducing the overall apparatus volume.
Solution Approach 2:
The piezoelectric actuator is designed to perform multiple functions: primary ejection actuation and secondary heating/viscosity control. By making the actuator universal, the patent eliminates the need for separate dedicated heater components, reducing the space required for component disposal and enabling apparatus size reduction while maintaining reliable ejection characteristics across varying liquid viscosities.
3Temperature
If non-ejection vibration pulse is supplied to the piezoelectric actuator in standby period, then the liquid is heated and viscosity is reduced, but energy is consumed during standby period
Solution Approach 1:
The patent implements periodic vibration pulse application during standby periods rather than continuous operation. The non-ejection vibration pulses are supplied at intervals to maintain liquid temperature and viscosity within acceptable ranges, rather than continuous heating. This periodic action reduces energy consumption compared to continuous heater operation while still achieving the desired temperature maintenance and viscosity control.
Solution Approach 2:
The system uses the piezoelectric actuator's vibration capability to self-regulate liquid viscosity and temperature during standby periods, eliminating the need for separate heating energy input. The mechanical vibration energy from the actuator serves dual purposes: maintaining ejection readiness by controlling liquid properties and reducing the need for additional energy-consuming heating systems.
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 allows for efficient heating and stabilization of the liquid within the ejecting apparatus, maintaining stable ejection characteristics without the complexity and size constraints associated with traditional heating mechanisms, thereby improving print quality and reducing apparatus size.
Implementation Method 1
a piezoelectric actuator which imparts a pressure fluctuation to the liquid in the pressure chamber
Implementation Method 2
a drive waveform generation section that generates a drive waveform including a non-ejection vibration pulse which, when supplied to the piezoelectric actuator, imparts the pressure fluctuation to the liquid in the pressure chamber such that the liquid is not ejected from the nozzle
Data Source
AI summary
A liquid ejecting apparatus includes an ejection section that includes a nozzle which ejects a liquid, a pressure chamber which communicates with the nozzle, and a piezoelectric actuator which imparts a pressure fluctuation to the liquid in the pressure chamber, a drive waveform generation section that generates a drive waveform including a non-ejection vibration pulse which, when supplied to the piezoelectric actuator, imparts the pressure fluctuation to the liquid in the pressure chamber such that the liquid is not ejected from the nozzle and a control section that controls supply of the non-ejection vibration pulse to the piezoelectric actuator in accordance with a temperature of the liquid in the pressure chamber.