Image Forming Apparatus Dynamic Print Speed Control
Solution Overview
Problem
Image forming apparatuses using low-temperature fixing toner face challenges in suppressing temperature rise, leading to reduced productivity and increased frequency of image defects like development stripes, as existing temperature rise suppression methods often require earlier mode switching and reduced throughput.
Innovation Solution
An image forming apparatus with a controller that switches between normal and temperature rise suppression modes based on environmental information and toner state indices, allowing for dynamic adjustment of print speed to maintain throughput while preventing defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If temperature rise suppression mode is activated when temperature reaches threshold value, then image defects caused by temperature rise are suppressed, but productivity is reduced due to earlier mode switching
Solution Approach 1:
The system continuously monitors temperature and dynamically adjusts print speed based on real-time temperature conditions. When temperature approaches the threshold, the print speed is gradually reduced rather than immediately switching modes, allowing the system to maintain high throughput while preventing temperature-induced image defects.
Solution Approach 2:
The patent implements dynamic print speed adjustment based on temperature conditions. The print speed is not fixed but varies continuously according to the current temperature state, enabling the system to optimize between productivity and image quality by adapting to changing thermal conditions in real-time.
2Use of energy by stationary object
If low-temperature fixing toner is used to reduce power consumption, then fixing temperature is decreased, but toner becomes more susceptible to temperature rise causing development stripes
Solution Approach 1:
The system takes preliminary action by monitoring temperature trends and adjusting print speed before temperature rise causes toner compaction and development stripes. By proactively reducing print speed when temperature approaches critical levels, the system prevents the harmful effect of toner susceptibility to temperature rise.
Solution Approach 2:
The system uses continuous temperature feedback to dynamically control print speed, creating a closed-loop control system that compensates for the increased temperature sensitivity of low-temperature fixing toner. This allows the system to maintain stable operation and prevent image defects while benefiting from the lower power consumption of low-temperature toner.
Data Source
AI summary
An image forming apparatus includes a latent image forming portion configured to form a latent image on an image bearing member; a developing device including a container configured to store toner and a developing member configured to supply the toner to the latent image formed on the image bearing member to form a toner image; an environment sensor configured to detect environmental information related to an environment in which the developing device is placed; and a controller configured to control switching between a first mode and a second mode, in which a number of prints per unit time is less than that in the first mode. The controller is configured to perform switching from the first mode to the second mode based on an update value obtained by adding or subtracting over time an index value weighted in accordance with the environmental information detected by the environment sensor.