Loom Warp Feeding Tension Control via Dual Motor Coordination

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing warp feeding technologies struggle to maintain stable tension during loom operations, particularly when a large tension deviation occurs, leading to hunting issues and prolonged stabilization time due to reliance on single motor control.

Innovation Solution

A method and device that utilize both let-off and take-up motors independently of the main driving motor to control warp tension by comparing detected tension values with reference values, allowing for simultaneous speed adjustments of both motors to quickly stabilize tension, reducing speed changes and hunting.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If only the let-off motor is controlled to maintain warp tension, then the control system is simple, but the tension stabilization time is prolonged and hunting occurs

Engineering Contradiction:
Improvecontrol system complexityVSAvoidtension stabilization time
Core Design Contradiction:
Device complexityVSLoss of time

Solution Approach 1:

The patent divides the tension control function into two independent segments: one for the let-off motor and one for the take-up motor. Each motor has its own control unit that independently adjusts its rotational speed based on tension deviations, allowing parallel processing of control actions and reducing overall stabilization time without increasing system complexity

Inventive Principle:
Principle #1Segmentation

2Speed

If the let-off motor speed is greatly increased to eliminate large tension deviation, then the tension is quickly reduced, but the rotational speed cannot be returned to the reference value on time

Engineering Contradiction:
Improvelet-off motor speed adjustmentVSAvoidrotational speed return time
Core Design Contradiction:
SpeedVSLoss of time

Solution Approach 1:

The patent applies preliminary action by having the take-up motor control unit anticipate and compensate for the speed changes of the let-off motor. When the let-off motor speed is adjusted to eliminate tension deviation, the take-up motor control unit simultaneously adjusts its speed in the opposite direction, preparing the system to return to the reference rotational speed without delay

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The take-up motor acts as an intermediary element that mediates between the let-off motor's speed changes and the final reference rotational speed. By coordinating its own speed adjustments in response to let-off motor changes, the take-up motor enables smooth transition and timely return to the reference state

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stress or pressure

If the let-off motor speed is greatly increased to eliminate tension deviation, then the tension is reduced, but the tension exceeds the reference value and increases due to hunting

Engineering Contradiction:
Improvewarp tensionVSAvoidtension stability
Core Design Contradiction:
Stress or pressureVSReliability

Solution Approach 1:

The patent implements feedback control where the control units continuously monitor the actual warp tension and compare it with the reference tension value. Based on the deviation, each control unit adjusts its motor's rotational speed in the appropriate direction, creating a closed-loop system that prevents tension from exceeding the reference value and eliminates hunting oscillations

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent changes the control parameter from single-motor speed adjustment to coordinated two-motor speed adjustment. By simultaneously adjusting the rotational speeds of both the let-off motor and take-up motor in opposite directions, the system achieves smoother tension control and prevents the hunting phenomenon that occurs with single-motor control

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2479326B1Loom with warp feeding device and warp feeding method
Publication Date: 2015.06.10 TSUDAKOMA KOGYO KK
  • EP2479326B1 patent drawingFigure 1
  • EP2479326B1 patent drawingFigure 2
  • EP2479326B1 patent drawingFigure 3

AI summary

A warp feeding method in a loom in which a let-off device (5) and a take-up device (8) have a let-off motor (5c) and a take-up motor (8c) as driving sources, respectively, is provided. The let-off motor (5c) and the take-up motor (8c) are independent of a main driving motor of the loom. The method includes the steps of performing a warp feeding operation by driving the let-off motor (5c) and the take-up motor (8c) while the main driving motor is stopped; during the warp feeding operation, detecting a tension of a warp; comparing a warp tension value that is based on the detection with a previously set reference value of the tension of the warp; and if the warp tension value is not the reference value, performing tension control for returning the tension of the warp to the reference value in accordance with a previously set control mode in which the let-off motor (5c) and the take-up motor (8c) are control objects.