Planetary Gear Drive Device with Floating Carrier for Image Forming Apparatus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive devices using planetary gear reduction systems in image forming apparatuses face inaccuracies in positioning and rotational fluctuations due to component variations and assembly tolerances, leading to speed fluctuations and image quality issues like jitter and banding.
Innovation Solution
A drive device with a 2KH-type two-stage planetary gear reduction system, where the central axes of sun gears, outer gears, carriers, and output shafts are coaxial, and at least one carrier is floatingly supported relative to the outer gear, with integrated carrier units and hollow cylindrical joints to minimize misalignment and rotational fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional planetary gear reduction devices are used with multiple support points for carriers, then assembly is easier and structure is more stable, but manufacturing precision and rotational accuracy deteriorate due to accumulated tolerances
Solution Approach 1:
The patent extracts the support function from multiple distributed support points and concentrates it into a single support point for each carrier. This eliminates the accumulation of assembly tolerances that would occur across multiple support points, thereby maintaining rotational accuracy while still allowing easy assembly through the simplified single-point support structure.
Solution Approach 2:
The single support point structure serves multiple functions: it provides structural support for the carrier, ensures precise rotational positioning, and simplifies the assembly process. By making the support point multi-functional, the patent avoids the need for multiple separate support components that would accumulate tolerances.
2Stability of the object's composition
If more support points are provided for planetary gears and carriers, then structural stability improves, but device complexity and installation space increase
Solution Approach 1:
The patent extracts the essential support function and isolates it to a single critical support point for each carrier, removing unnecessary support points that would add complexity. This single support point is strategically positioned to provide maximum structural stability while minimizing the number of components.
Solution Approach 2:
Instead of adding more support points to achieve stability, the patent inverts the approach by using fewer, more strategically positioned support points. The single support point is designed with enhanced load-bearing characteristics to provide the necessary stability without increasing component count.
3Adaptability or versatility
If conventional positioning methods are used with multiple contact points, then assembly flexibility is better, but positioning accuracy deteriorates due to tolerance accumulation
Solution Approach 1:
The patent extracts the positioning function from multiple contact points and concentrates it into a single precision support point. This single point provides accurate positional reference for the carrier while the overall design maintains assembly flexibility through tolerant mounting interfaces at non-critical locations.
Data Source
AI summary
A drive device including a planetary gear reduction device having at least two stages and an output shaft, and a driven shaft to support a driven member rotatively driven by torque reduced by the planetary gear reduction device and transmit the torque from the output shaft to the driven member. Each stage of the planetary gear reduction device includes a sun gear, an outer gear, multiple planetary gears, a carrier, and a support shaft. The output shaft is provided to the carrier of the last stage. Central axes of the sun gear, the outer gear, the carrier, the output shaft, the driven shaft, and the driven member are all arranged coaxially with one another and at least one carrier is floatingly supported relative to the outer gear. The carrier is formed as a single integrated unit having holes into which both ends of the support shaft are fitted.