Drive Circuit Positioning to Prevent Ink Mist Faults
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In liquid discharge apparatuses, such as ink jet printers, the drive circuit mounted on a carriage is prone to faults due to ink mist attaching and causing short circuits, and existing solutions do not effectively address the positioning of the drive circuit to prevent mist attachment, leading to printing quality issues and increased power consumption.
Innovation Solution
The drive circuit is positioned on a surface of the carriage that moves away from the flushing box and home position, avoiding areas where ink mist is likely to accumulate, and uses a class D amplifier to reduce power consumption and heat generation, with an optional regeneration circuit for further energy efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the drive circuit is mounted on the carriage, then the transfer path for driving signals is shortened and waveform distortion is reduced, but the drive circuit is exposed to ink mist that causes short circuits and faults
Solution Approach 1:
The drive circuit is extracted from the carriage and mounted on the printer body instead. This separates the drive circuit from the ink mist environment while maintaining short signal transfer paths through direct mounting near the head unit, thus resolving the contradiction between signal reliability and mist exposure.
Solution Approach 2:
A flexible printed circuit board (FPC) is introduced as an intermediary component to transmit driving signals from the printer body to the head unit. This allows the drive circuit to remain on the printer body away from ink mist while maintaining effective signal transmission to the nozzles.
2Power
If a class AB amplifier is used in the drive circuit, then sufficient current is supplied to piezoelectric elements, but power consumption and heat generation increase
Solution Approach 1:
The amplifier class is changed from class AB to class D, which fundamentally alters the operating parameters and efficiency characteristics. Class D amplifiers use switching operation instead of linear amplification, dramatically reducing power consumption and heat generation while maintaining sufficient current supply capability to the piezoelectric elements.
3Length of stationary object
If the drive circuit is mounted on the carriage, then signal transfer path is shortened, but the carriage weight and size increase due to heat sink requirements
Solution Approach 1:
The drive circuit and its associated heat sink are extracted from the carriage and mounted on the printer body. This eliminates the weight and size burden on the moving carriage while maintaining short effective signal transfer paths through strategic mounting positions and use of FPC interconnects.
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 configuration reduces faults caused by ink mist attachment, improves printing quality, and enhances energy savings by minimizing heat generation and extending motor lifespan.
Implementation Method 1
piezoelectric elements are provided to correspond to a plurality of nozzles in a recording head and dots are formed by specific amounts of ink (liquid) being discharged at specific timings from the nozzles due to each of the piezoelectric elements being driven
Implementation Method 2
Japanese Patent Application Publication No. 2014-076567 discloses a technique for reducing the distorting of the driving waveforms by the carriage being mounted with a drive circuit which uses a class D amplifier as the amplification circuit
Data Source
AI summary
A liquid discharge apparatus has a head provided with discharge sections which discharge a liquid, a drive circuit configured to generate driving signals for driving the discharge sections and discharging the liquid, a carriage mounted with the head and the drive circuit, a motor configured to move the carriage, and a flushing box configured and arranged to receive the liquid discharged from the discharge sections. The drive circuit is mounted at a position so as not to pass above the flushing box while the carriage is being moved.