Segmented Linear Motor Curved Path Positioning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional conveyance systems with linear transport paths face limitations in utilizing factory floor space efficiently due to low positioning accuracy at curved sections, which restricts the precise delivery and receipt of workpieces and limits the arrangement of machines and equipment.

Innovation Solution

A conveyance system utilizing a linear motor with armatures spaced along the travel guide, allowing precise movement and halting of the traveling member at curved sections, combined with non-contact power feeding and wireless communication for eliminating cables and wiring, enabling precise positioning and efficient use of curved paths.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of stationary object

If a linear induction motor is used for long distance conveyance, then the conveyance system can achieve long distance transport, but the positioning accuracy at curved sections becomes insufficient

Engineering Contradiction:
Improveconveyance distanceVSAvoidpositioning accuracy
Core Design Contradiction:
Length of stationary objectVSMeasurement precision

Solution Approach 1:

The linear motor is divided into multiple independent motor units along the conveyance path. Each unit can be independently controlled to provide precise positioning at specific locations, particularly at curved sections where high positioning accuracy is required, while maintaining the capability for long distance conveyance through coordinated operation of multiple units.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different sections of the conveyance path are equipped with different motor unit configurations. Curved sections have densely arranged motor units for high positioning accuracy, while straight sections have sparser arrangement for energy efficiency. This local differentiation resolves the contradiction between long distance conveyance and positioning accuracy at critical locations.

Inventive Principle:
Principle #3Local quality

2Measurement precision

If the coil side of the linear synchronous motor is made movable to improve positioning accuracy, then positioning performance increases, but the power feeding system becomes complicated and endless transport path is impossible

Engineering Contradiction:
Improvepositioning accuracyVSAvoidpower feeding system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Instead of making the coil side movable (secondary side), the invention makes the armature side (primary side) movable by using multiple independent motor units that can be selectively activated. This inversion allows the stationary side to remain simple with fixed coils, eliminating the need for complex power feeding to moving parts while achieving high positioning accuracy through selective activation of motor units along the path.

Inventive Principle:
Principle #13The other way round (Inversion)

3Device complexity

If a rotary servomotor with rack and pinion is used, then the drive mechanism is simple, but positioning accuracy cannot be increased

Engineering Contradiction:
Improvedrive mechanism simplicityVSAvoidpositioning accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The invention replaces the mechanical rack and pinion system with a linear motor system that uses electromagnetic force for direct linear motion. This substitution eliminates mechanical transmission errors and backlash inherent in rack and pinion systems, achieving high positioning accuracy while maintaining relative simplicity through the use of standardized motor units.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Speed

If the primary coil is disposed on the ground side in localized areas, then acceleration and deceleration can be achieved, but the curved section cannot be utilized for precise workpiece transfer

Engineering Contradiction:
Improveacceleration and deceleration capabilityVSAvoidworkpiece transfer precision
Core Design Contradiction:
SpeedVSMeasurement precision

Solution Approach 1:

The primary coil arrangement is segmented into multiple discrete motor units distributed along the entire conveyance path, not just in localized acceleration/deceleration zones. This segmentation allows precise control at any position including curved sections, enabling both speed control and high-precision workpiece transfer by selectively activating appropriate motor units.

Inventive Principle:
Principle #1Segmentation

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 assured and precise delivery and receipt of workpieces at curved sections, optimizing factory floor space utilization and reducing the complexity of power feeding systems while ensuring proper posture and grasping positions.

Implementation Method 1

a linear motor comprised of armatures, installed on the ground side along a travel guide, and a mover on a secondary side installed on the traveling member

Methodology Applied
Scientific EffectElectromagnetic force: Lorentz Force

Data Source

PatentEP2633946B1Conveyance system
Publication Date: 2016.04.06 MURATA MASCH LTD
  • EP2633946B1 patent drawingFigure 1
  • EP2633946B1 patent drawingFigure 2~3
  • EP2633946B1 patent drawingFigure 4~5

AI summary

A conveyance system includes a traveling member (3) to transport an article installed for movement along a travel guide (4). A drive source for driving the traveling member (3) to move is a linear motor (5) comprised of an armature (6), disposed along the travel guide (4), and a mover (7) on the secondary side installed on the traveling member (3). The travel guide (4) has a rectilinear section (4A) and a curved section (4B). The armatures (6) of the linear motor (5) are arranged having been spaced a distance from each other and arranged in a plural number along the rectilinear section (4A) and the curved section (4B) of the travel guide (4). The travel guide (4) is of a type capable of accommodating a plurality of traveling members (3) mounted thereon.