Eccentric Shared-Input Speed Reducer for High Ratio in Less Space

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Traditional speed reducers with two independent annular input gears result in complex structures, increased cost, larger volume, and poor structural strength, making it difficult to achieve a high reduction ratio while minimizing components and volume.

Innovation Solution

A speed reducer design featuring a shared input gear with an eccentric structure, where the input gear forms gear pairs with both the fixing gear and output gear, reducing the number of components and eliminating the need for fixing holes, thereby achieving a high reduction ratio with less complexity and stronger structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If two independent annular input gears are used, then a high reduction ratio can be achieved, but the structure becomes complicated with more components and larger volume

Engineering Contradiction:
Improvereduction ratioVSAvoidstructural complexity
Core Design Contradiction:
PowerVSDevice complexity

Solution Approach 1:

The patent merges two independent annular input gears into a single integrated input gear structure. This single input gear has an eccentric structure that allows it to simultaneously engage with both the fixing gear and the output gear, thereby achieving the same high reduction ratio while reducing the number of components and simplifying the overall structure.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The single input gear is designed to perform multiple functions: it serves as both the first input gear and the second input gear in traditional designs. The eccentric structure enables this single component to interact with two different gears (fixing gear and output gear) to achieve the compound reduction effect, making the input gear universal and multi-functional.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Power

If two independent annular input gears are used, then a high reduction ratio can be achieved, but the volume of the speed reducer increases

Engineering Contradiction:
Improvereduction ratioVSAvoidspeed reducer volume
Core Design Contradiction:
PowerVSVolume of stationary object

Solution Approach 1:

By combining two separate input gears into one integrated eccentric input gear, the patent eliminates the space required for two separate gear components and their mounting structures. This merging directly reduces the overall volume of the speed reducer while maintaining the high reduction ratio through the eccentric mechanism.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The eccentric structure allows the input gear to effectively 'nest' its dual functionality within a single component footprint. The eccentric mechanism enables the single input gear to achieve the compound reduction effect that previously required two separate gears, thereby nesting the functional equivalent of two gears into one space-efficient component.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Power

If two independent annular input gears are used, then a high reduction ratio can be achieved, but the structural strength deteriorates

Engineering Contradiction:
Improvereduction ratioVSAvoidstructural strength
Core Design Contradiction:
PowerVSStrength

Solution Approach 1:

The patent combines two separate input gears into a single integrated structure with an eccentric design. This merging creates a more robust structural unit that distributes mechanical loads more effectively across a unified component, thereby improving overall structural strength while maintaining the high reduction ratio functionality.

Inventive Principle:
Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The shared input gear design allows for a high reduction ratio, reduced component count, lower costs, and enhanced structural strength, while minimizing volume and eliminating the need for complex machining, resulting in a more efficient and cost-effective speed reducer.

Implementation Method 1

the input gear is rotated with the input shaft and eccentrically rotated about an axel center of the input shaft

Methodology Applied
Scientific EffectEccentric rotation: Eccentric

Implementation Method 2

the first teeth are pushed against the corresponding third teeth so that the output gear is correspondingly rotated

Methodology Applied
Scientific EffectGear contact force: Gear

Data Source

PatentEP4155577A1Speed reducer
Publication Date: 2023.03.29 DELTA ELECTRONICS INC(CN)
  • EP4155577A1 patent drawingFigure 1
  • EP4155577A1 patent drawingFigure 2
  • EP4155577A1 patent drawingFigure 3

AI summary

A speed reducer (1, 1a) includes an input shaft (10, 10a), an input gear (11, 11a), a fixing gear (12, 12a) and an output gear (13, 13a). The input shaft (10, 10a) includes an eccentric structure (10b). The input gear (11, 11a) is disposed on the eccentric structure (10b) and includes first teeth (110, 110a) of which each with a first contact portion and a second contact portion. The fixing gear (12, 12a) and the output gear (13, 13a) are disposed corresponding to the input gear (11, 11a), wherein the fixing gear (12, 12a) includes second teeth (120, 120a), and the second teeth (120, 120a) are in contact with the first contact portions, wherein the output gear (13, 13a) includes third teeth (130, 130a), and the third teeth (130, 130a) are in contact with the second contact portions. A first tooth number difference between the first teeth (110, 110a) and the second teeth (120, 120a) is different from a second tooth number difference between the first teeth (110, 110a) and the third teeth (130, 130a).