Roller Drive With Friction Coupling and Plastic Gears

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing roller drives face challenges in achieving high speed translation in a compact space while protecting the electric motor and gearbox from overload, and require lubrication, which complicates the design.

Innovation Solution

A roller drive system where an electric motor drives a transport roller through an epicyclic gear with a non-positive connection, using a disc mounted on a rotor shaft via a bearing, connected to a cheek via axially arranged bolts, allowing for coaxial planetary gear operation and eliminating the need for lubrication by using plastic components and metal bolts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If an epicyclic gear is used to achieve high speed translation in a compact space, then the speed translation is improved, but the risk of overload damage to the motor and gearbox increases

Engineering Contradiction:
Improvespeed translationVSAvoidoverload protection
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The patent changes the connection parameter from rigid to frictional by using a friction wheel instead of a rigid coupling between the epicyclic gear output and the transport roller. This allows the system to maintain high speed translation while providing overload protection through the friction connection that slips under excessive load.

Inventive Principle:
Principle #35Parameter changes

2Strength

If traditional mechanical components are used in the gearbox, then the structural strength is improved, but the requirement for lubrication increases device complexity

Engineering Contradiction:
Improvestructural strengthVSAvoidlubrication requirement
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent changes the material parameter from traditional metal-on-metal contact to plastic-metal contact by using plastic gears and a metal friction wheel. This parameter change eliminates the need for lubrication while maintaining sufficient structural strength for the application.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs composite material selection by combining plastic components (gears, friction wheel) with metal bolts and housing elements. This composite approach provides the necessary strength while eliminating lubrication requirements that would be needed with traditional all-metal constructions.

Inventive Principle:
Principle #40Composite materials

3Power

If a rigid connection is used between the gearbox output and transport roller, then the power transmission efficiency is improved, but the protection against overload is reduced

Engineering Contradiction:
Improvepower transmission efficiencyVSAvoidoverload protection
Core Design Contradiction:
PowerVSReliability

Solution Approach 1:

The patent changes the connection parameter from rigid to frictional by using a friction wheel that contacts the output disc of the epicyclic gear. This frictional connection provides sufficient power transmission for normal operation while automatically slipping to protect against overload conditions.

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

Enables high speed translation in a compact space with overload protection and reduced wear, eliminating the need for lubrication, thus simplifying the design and enhancing operational reliability.

Implementation Method 1

the relative speed between the inner ring and outer ring of the bearing can be reduced because the radius is smaller than in an arrangement in which the outer ring of the bearing is arranged on the hollow part and the inner ring on the cheek

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

The cheek is mounted on the hollow part or on the motor housing via a bearing, in particular a ball bearing

Methodology Applied
Scientific EffectRolling contact: Ball Bearing

Implementation Method 3

A respective bolt receives a respective rotating disk, which is in contact with the hollow part, which is fixed to the motor housing, and with the cyclo-disc, which is fixed for rotation with the rotor shaft

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 4

the cyclone disc, the hollow part and/or the revolving discs are made of plastic. The advantage here is that no lubricant is required in the gearbox

Methodology Applied
Scientific EffectFriction reduction through material selection: Friction

Data Source

PatentEP2556002B1Roller drive
Publication Date: 2014.06.25 SEW EURODRIVE GMBH & CO KG
  • EP2556002B1 patent drawingFigure 1
  • EP2556002B1 patent drawingFigure 2
  • EP2556002B1 patent drawingFigure 3

AI summary

The invention relates to a roller drive, wherein a transport roller (42) is driven by an electric motor arranged within the transport roller (42), the rotor shaft (1) of the electric motor being rotatably supported relative to the housing of the motor, wherein the rotor shaft (1) is the driving shaft of a planetary gear train or is connected to the driving shaft in a rotationally fixed manner, and the output of the gear train is non-positively connected to the transport roller (42), in particular