Epicyclic Gearbox Superimposing Motor Torque for Wide Speed Range

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Solution Overview

Problem

Conventional geared motors and manual transmissions face inefficiencies in part-load operation and low speeds, and they typically achieve lower torque at high speeds compared to low speeds, failing to optimize efficiency and torque delivery across a wide range.

Innovation Solution

A geared motor system incorporating an epicyclic gearbox with two electric motors, where one motor drives the gearbox's first gear stage and another motor drives additional gear stages, allowing for constant high torque generation across a wide speed range by superimposing rotary movements, and a controller regulates motor speeds and torques for optimal efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If a geared motor is designed for full-load operation, then it can drive the nominal load, but it does not achieve optimum efficiencies in part-load operation or at low speeds

Engineering Contradiction:
Improvefull-load capabilityVSAvoidefficiency in part-load operation
Core Design Contradiction:
PowerVSLoss of energy

Solution Approach 1:

The transmission system is divided into multiple independent gear stages (first gear stage, second gear stage, third gear stage) that can be selectively engaged. This segmentation allows the system to optimize the transmission path for different operating conditions, achieving high efficiency in both full-load and part-load operations by selecting the most appropriate gear stage for the current demand.

Inventive Principle:
Principle #1Segmentation

2Device complexity

If a single motor drives all gear stages, then the structure is simpler, but the efficiency is not optimal across varying loads and speeds

Engineering Contradiction:
Improvemotor configurationVSAvoidefficiency across varying loads
Core Design Contradiction:
Device complexityVSLoss of energy

Solution Approach 1:

Multiple electric motors are combined to drive different gear stages simultaneously or independently. This merging of motor resources allows the system to optimize efficiency across varying loads by distributing the driving task among multiple motors, each operating in its optimal efficiency range, while maintaining a relatively compact integrated structure.

Inventive Principle:
Principle #5Merging (Combining)

3Speed

If the geared motor operates at variable speeds, then it can adapt to different applications, but the torque delivery is not constant across the speed range

Engineering Contradiction:
Improvespeed rangeVSAvoidtorque constancy
Core Design Contradiction:
SpeedVSForce

Solution Approach 1:

The system changes transmission parameters (gear stage selection, motor speed ratios) based on the operating conditions. By selectively engaging different gear stages and adjusting motor speeds, the system maintains substantially constant torque delivery across a wide speed range, with the torque remaining within 5% of the maximum value throughout the permissible operating range.

Inventive Principle:
Principle #35Parameter changes

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

This configuration ensures constant and high torque delivery across a wide speed range, optimizing efficiency and energy savings, making it suitable for applications with varying loads and reducing environmental impact.

Implementation Method 1

a first electric motor M1 for driving a first toothed part of a superimposed gear G and a second electric motor M2 for driving a second toothed part of the superimposed gear G

Methodology Applied
Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Implementation Method 2

superimposing rotary movements, and a controller regulates motor speeds and torques for optimal efficiency

Methodology Applied
Scientific EffectMechanical advantage through gear superposition: Gear

Implementation Method 3

A geared motor system incorporating an epicyclic gearbox with two electric motors, where one motor drives the gearbox's first gear stage and another motor drives additional gear stages

Methodology Applied
Scientific EffectEpicyclic gearing mechanism: Epicyclic Gearing

Data Source

PatentEP2337972B1Transmission engine, transmission system and method for operating a system
Publication Date: 2016.01.06 SEW EURODRIVE GMBH & CO KG
  • EP2337972B1 patent drawingFigure 1
  • EP2337972B1 patent drawingFigure 2

AI summary

The invention relates to a transmission engine, to a transmission system and to a method for operating a system, comprising a transmission driven by an engine, wherein the transmission comprises gear components, wherein a further engine drives one of the gear components.