Pulse Generator High Impedance Stray Capacitance Inkjet
Solution Overview
Problem
Inkjet heads of the share mode type experience noise and unnecessary power consumption due to stray capacitance, which occurs when voltages of the same potential are applied to adjacent ink chambers, leading to inefficient operation.
Innovation Solution
A pulse generator is designed to set specific electrodes to a high impedance state at appropriate timing, using a configuration that includes ejection relevant and ejection both-side waveform setting registers, high impedance setting registers, and a waveform forming unit to output driving pulses that prevent stray capacitance charging or discharging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If voltages of the same potential are simultaneously applied to electrodes of adjacent ink chambers, then the inkjet head can operate with simplified control, but stray capacitance causes noise and unnecessary power consumption
Solution Approach 1:
The patent applies different voltage patterns to different ink chambers based on their specific operational requirements. Ejection-related ink chambers receive one voltage pattern while ejection-both-side ink chambers receive another pattern, allowing each region to be optimized for its function while minimizing stray capacitance effects in specific locations
Solution Approach 2:
The pulse generator preliminarily sets electrodes to high impedance state before applying voltages of the same potential to adjacent ink chambers. This preliminary action prevents stray capacitance charging or discharging from occurring, thereby eliminating noise and unnecessary power consumption before the problematic voltage application happens
2Ease of operation
If voltages of the same potential are simultaneously applied to electrodes of adjacent ink chambers, then the driving pulse control is simplified, but noise is generated due to stray capacitance charging or discharging
Solution Approach 1:
Different voltage patterns are applied to different ink chambers based on their functional requirements. Ejection-related ink chambers use one voltage pattern while ejection-both-side ink chambers use another, allowing localized optimization that prevents noise generation in specific critical regions
Solution Approach 2:
The pulse generator preliminarily sets electrodes to high impedance state before applying voltages of the same potential to adjacent ink chambers. This preliminary action prevents stray capacitance charging or discharging from occurring, thereby eliminating noise before it can be generated
3Loss of energy
If electrodes are set to high impedance state to suppress stray capacitance effects, then noise and power consumption are reduced, but the device complexity increases due to additional control logic
Solution Approach 1:
The waveform forming unit generates multiple types of driving pulses (ejection-related, ejection-both-side, and other driving pulses) using a unified control architecture. The high impedance setting is integrated into the existing pulse generation logic rather than adding a separate control system, thereby reducing overall device complexity while still achieving energy savings
Solution Approach 2:
The pulse generator uses timing information and voltage pattern requirements as feedback to automatically determine when electrodes should be set to high impedance state. This automated feedback mechanism eliminates the need for complex manual control logic while ensuring proper timing of high impedance states to suppress stray capacitance effects
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 effectively suppresses noise and power consumption by ensuring that electrodes are in a high impedance state when voltages of the same potential are applied, thereby preventing stray capacitance-induced issues and maintaining efficient inkjet operation.
Implementation Method 1
a plurality of ink chambers partitioned by partition walls made of a piezoelectric material are provided side by side
Data Source
AI summary
A pulse generator forms, from setting data respectively stored in an ejection relevant waveform setting register and a first high impedance setting register, an ejection relevant driving pulse for setting an electrode of an ink chamber communicating with an ejection relevant nozzle to a high impedance state for a predetermined period. The pulse generator forms, from setting data respectively stored in an ejection both-side waveform setting register and a second high impedance setting register, an ejection both-side driving pulse for setting electrodes of ink chambers communicating with ejection both-side nozzles to the high impedance state for the predetermined period. The pulse generator outputs signals of the formed driving pulses to an inkjet head.