Liquid Discharge Head Drive Waveform for Satellite Droplet Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid discharge technologies face challenges in restraining satellite droplets caused by tailing of main droplets, as conventional driving waveforms do not effectively manage the timing and peak values of non-discharge and discharge pulses to prevent satellite formation.
Innovation Solution
A liquid discharge apparatus and method that generates a drive waveform with a non-discharge pulse and a discharge pulse, where the time interval between them (Td) is set within a specific range relative to the natural vibration period (Tc) of the pressure chamber, and the peak value of the non-discharge pulse (Vp1) is adjusted to be within a certain percentage of the peak value of the discharge pulse (Vp2), optimizing the meniscus vibration to prevent satellite droplet formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a conventional drive waveform is used to discharge liquid, then liquid discharge function is achieved, but satellite droplets are generated due to tailing of main droplets
Solution Approach 1:
A non-discharge pulse is applied before the discharge pulse to preliminarily excite the pressure chamber and establish resonant vibration. This preliminary action prepares the system in an optimal state for subsequent liquid discharge, ensuring that the main droplet is discharged cleanly without satellite droplets by pre-synchronizing the chamber vibration with the upcoming discharge pulse.
Solution Approach 2:
The drive waveform employs periodic pulsing with a specific time interval Td between non-discharge and discharge pulses. This periodic action exploits the natural resonance frequency of the pressure chamber, creating rhythmic vibrations that facilitate clean droplet ejection. The periodic non-discharge pulses maintain resonant conditions that prevent satellite droplet formation during the discharge phase.
2Object-generated harmful factors
If the time interval between non-discharge pulse and discharge pulse is not optimized, then satellite droplets occur, but with optimized timing satellite-less discharge is achieved
Solution Approach 1:
The invention optimizes specific parameters of the drive waveform: the time interval Td between non-discharge and discharge pulses is set to a specific value or range, and the peak value Vp1 of the non-discharge pulse is set to a specific value or range. By precisely controlling these parameters, the system achieves satellite-less discharge while maintaining manageable waveform complexity.
3Object-generated harmful factors
If the peak value of non-discharge pulse is not optimized, then satellite droplets are generated, but with optimized peak value discharge stability is enhanced
Solution Approach 1:
The peak value Vp1 of the non-discharge pulse is set to a specific value or range to optimize the vibration amplitude established before discharge. This parameter optimization ensures that the meniscus is properly positioned and the liquid is pre-conditioned for clean ejection, preventing satellite droplets while maintaining consistent and controllable droplet speeds for high discharge stability.
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
The proposed solution effectively restrains satellite droplets by optimizing the timing and peak values of the pulses, ensuring efficient energy transmission and preventing overflow, thereby achieving a satellite-less discharge state with enhanced droplet speed and discharge stability.
Implementation Method 1
Td represents a time interval between the non-discharge pulse and the discharge pulse, Tc represents a natural vibration period of a pressure chamber of the liquid discharge head
Data Source
AI summary
A liquid discharge apparatus includes a liquid discharge head to discharge liquid and control circuitry to generate a drive waveform including drive pulses applied to the head. The drive waveform includes a non-discharge pulse not to discharge the liquid and a discharge pulse to discharge the liquid. The non-discharge pulse and the discharge pulse are serial in time in the drive waveform. Td is in a range of Tc−0.2×Tc to Tc+0.45×Tc. Vp1 is in a range of −10% to +10% of Vpp1. Td represents a time interval between the non-discharge pulse and the discharge pulse. Tc represents a natural vibration period of a pressure chamber of the head. Vp1 represents a peak value of the non-discharge pulse. Vpp1 represents a peak value of the non-discharge pulse at which a droplet speed of liquid discharged by the discharge pulse takes a local minimum value.