Relay Circuit Board Isolates Static Electricity in Printers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In printing apparatuses, electrostatic charges from users can cause static electricity to propagate to display control circuit boards, leading to distorted displays due to direct coupling between mechanical switches and display control circuit boards.
Innovation Solution
The printing apparatus is designed with a relay circuit board that couples mechanical switches to the main circuit board, while maintaining a shorter distance between mechanical switches and display control circuit boards, thereby reducing the propagation of static electricity to the display control circuit boards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the mechanical switch is directly coupled to the display control circuit board, then the device complexity is reduced, but static electricity propagates to the display control circuit board causing display distortion
Solution Approach 1:
A relay circuit board is introduced as an intermediary component between the mechanical switch and the display control circuit board. The relay circuit board includes a relay that electrically connects to the mechanical switch and another relay that electrically connects to the display control circuit board, thereby mediating the electrical connection and preventing direct static electricity propagation while maintaining functional connectivity.
Solution Approach 2:
The direct coupling between the mechanical switch and display control circuit board is segmented into multiple stages: the mechanical switch connects to the relay circuit board, which then connects to the display control circuit board. This segmentation isolates the display control circuit board from direct exposure to static electricity from the mechanical switch.
2Object-affected harmful factors
If the relay circuit board is introduced to block static electricity, then the harmful effect of static electricity is reduced, but the device complexity increases
Solution Approach 1:
The relay circuit board serves multiple functions: it blocks static electricity propagation to the display control circuit board, maintains electrical connectivity between the mechanical switch and display control circuit board, and provides a centralized location for relay components that can protect multiple circuit paths. This multi-functionality justifies the added complexity by delivering multiple benefits from a single structural addition.
Data Source
AI summary
A printing apparatus has: a manipulation circuit board on which a display control circuit that controls a display is mounted, the manipulation circuit board being coupled to the display; a relay circuit board coupled to the manipulation circuit board through first wiring; a main circuit board on which a print control circuit that controls a printing mechanism is mounted, the main circuit board being coupled to the relay circuit board through second wiring; and a home switch coupled to the relay circuit board through third wiring, without any of the manipulation circuit board and main circuit board intervening between the home switch and the relay circuit board. The distance between the home switch and the manipulation circuit board is smaller than the distance between the home switch and the relay circuit board.