Image Forming Apparatus Tray Lift Mechanism
Solution Overview
Problem
The existing image forming apparatus experiences performance fluctuations and paper jams due to changes in the number of printing media stacked on the tray, as the angle of the tray and the entry position of the printing medium into the guide unit change, affecting the separation of multiple printing media.
Innovation Solution
The apparatus includes a lift mechanism with a motor, a first conveying unit, a second conveying unit, and a control unit that adjusts the position of the first conveying unit based on the movement amount of the tray, ensuring the guide unit can effectively separate multiple printing media by adjusting the contact position according to the number of media stacked, preventing performance fluctuations and jams.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the number of printing media stacked on the tray changes, then the tray angle and entry position change, but the separation performance of the guide unit becomes unstable
Solution Approach 1:
The guide unit is designed with a movable guide member that can dynamically adjust its position along the conveying direction. When the number of printing media changes, the guide member automatically shifts to a new equilibrium position where the combined weight of the media stack creates sufficient downward force on the media, ensuring consistent separation performance regardless of stack height. This dynamic adjustment eliminates the need for manual intervention and maintains reliable operation across varying media quantities.
2Ease of operation
If the tray lifts with different numbers of printing media, then the entry position into the guide unit changes, but this causes performance fluctuations in separation
Solution Approach 1:
A movable guide member acts as an intermediary between the tray and the fixed guide structure. This guide member can shift position along the conveying direction to compensate for variations in tray lift height caused by different media stack weights. By absorbing these position variations, the intermediary guide member ensures that printing media consistently enter the separation zone at the correct angle and position, maintaining high precision separation performance while preserving the simplicity of automatic tray lifting operation.
3Device complexity
If the guide unit is fixed in position, then the structure is simple, but it cannot adapt to changes in printing media quantity
Solution Approach 1:
The guide unit incorporates a movable guide member that can shift position along the conveying direction in response to changes in printing media quantity. The guide member is designed with low-friction movement capabilities, allowing it to automatically adjust its position based on the weight of the media stack. This dynamic design provides adaptability to varying media quantities while maintaining relatively simple construction, avoiding the need for complex active control systems or multiple adjustable components.
Data Source
AI summary
An image forming apparatus includes a paper feeding cassette, a first conveying unit, a lift mechanism, a motor, a second conveying unit, and a control unit. The controller drives the motor and, if a value indicating a movement amount of the tray moving from when the lift mechanism starts the lifting of the tray until when a position of the top part reaches a first position is a first value, matches a position of the first conveying unit, which comes into contact with the top part to thereby rise together with the tray, with a second position and, if the value indicating the movement amount is a second value larger than the first value, matches the position of the first conveying unit, which comes into contact with the top part to thereby rise together with the tray, with a third position lower than the second position.