Developing Apparatus Pressure Relief Valve Toner Spouting
Solution Overview
Problem
Existing developing apparatuses face issues with toner spouting out due to increased internal pressure, leading to reduced image quality and filter clogging, which necessitates frequent maintenance and replacement.
Innovation Solution
A developing apparatus configuration that includes a supply path, discharge path, developer holding portion, and accommodation portion with a controlled space volume to manage internal pressure, preventing toner spouting through a balance of forces and volume adjustments, eliminating the need for filters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a filter is used to prevent internal pressure increase and toner spouting, then toner spouting is prevented initially, but the filter becomes clogged over time causing internal pressure to increase and toner to spout out
Solution Approach 1:
The invention removes the filter component entirely from the system. Instead of using a filter to regulate air flow and prevent pressure buildup, the patent employs a pressure relief valve that directly releases excess pressure when it exceeds a predetermined threshold, eliminating the maintenance issues associated with filter clogging while continuing to prevent toner spouting.
Solution Approach 2:
The invention changes the operational parameter from filter-based flow restriction to pressure-threshold-based valve activation. The pressure relief valve is designed to open at a specific pressure threshold, dynamically adjusting the venting mechanism based on real-time pressure conditions rather than relying on a static filter structure that degrades over time.
2Productivity
If the internal pressure in the developing apparatus increases during toner supply, then toner is supplied effectively, but the toner spouts out to the outside of the developing apparatus
Solution Approach 1:
The pressure relief valve is pre-configured to activate before toner spouting can occur. By setting the valve to open at a pressure threshold below the level that causes toner spouting, the system preemptively releases pressure buildup, preventing the harmful effect before it manifests.
Solution Approach 2:
The pressure relief valve acts as an intermediary mechanism between the pressure buildup during toner supply and the potential toner spouting. It mediates the pressure release in a controlled manner, allowing effective toner supply while preventing the harmful spouting effect through intermediate pressure regulation.
Data Source
AI summary
An image forming apparatus includes a developing apparatus including a housing having a supply opening to receive developer supplied by a pump unit, a developing device screw disposed in a discharge path of the housing to supply and discharge the developer through a discharge opening to an image bearing member, and a developer bearing portion having a magnetic body that generates a magnetic force and is configured to bear the developer with a carrying force working in a substantially perpendicular direction to the magnetic force. In addition, a developer accommodation portion within the housing accommodates the developer supplied from a supply opening and has no opening other than the supply opening and the discharge opening, with the developer accommodation portion having a space volume capable of suppressing a spouting force caused by an inner pressure increase due to operation of the pump unit.