ISO 441:1997

Overview

ISO 441:1997 is an international standard published by the International Organization for Standardization (ISO) that specifies the dimensions, tolerances, and designation of drop wires used in warp stop motions for weaving machines without automatic drawing-in. These drop wires, also known as "lamelles" or warp stop motion fingers, are critical components in textile machinery designed to detect thread breaks and stop the weaving process to prevent defective fabric production.

The standard applies to mechanical, electromechanical, and electrical warp stop motions, focusing exclusively on manually inserted or machine-pinned drop wires without automatic re-threading mechanisms. ISO 441:1997 offers uniformity in the manufacturing and specification of these components, facilitating compatibility and quality across the textile industry.

Key Topics

• Scope and Application
  ISO 441:1997 governs the geometric specifications for drop wires in weaving machines lacking automatic drawing-in. It covers four types of drop wires:

  • MG: Mechanical/Electromechanical with closed end
  • MO: Mechanical/Electromechanical with open end
  • EG: Electrical with closed end
  • EO: Electrical with open end

• Dimensions and Tolerances
  The standard provides detailed measurements and tolerances for these components, including length, width, thickness, and eyelet shape. Illustrative figures and tables define dimensional parameters to ensure interchangeability:

  • Length (L)
  • Width (b)
  • Thickness (e)
  • Eyelet shape (e.g., U-shaped, round)

• Designation System
  Drop wires are designated with a clear naming convention that includes:

  • The term "Lamelle" (drop wire)
  • Reference to ISO 441
  • Type of warp stop motion (M or E)
  • Eyelet closure type (G for closed, O for open)
  • Eyelet shape
  • Dimensions (length x width x thickness)

  Example: Lamelle ISO 441 - MGU 145 x 11 x 0.3 indicates mechanical drop wire with closed U-shaped eyelet, 145 mm long, 11 mm wide, and 0.3 mm thick.

Applications

ISO 441:1997 standardizes drop wires used extensively in the textile industry’s weaving operations, particularly for:

• Warp Stop Motions in Weaving Machines
  Designed for machines without automatic drawing-in features, these drop wires detect warp thread breaks and trigger the stop motion to prevent fabric defects or loom damage.

• Textile Machine Manufacturing and Maintenance
  Manufacturers rely on these standardized dimensions and designations to produce compatible drop wires for various mechanical, electromechanical, and electrical warp stop devices, facilitating replacement and maintenance.

• Quality Control in Textile Production
  Conformity with ISO 441 ensures reliable and consistent warp stop performance, enhancing machine uptime and product quality by minimizing faults caused by broken warp threads.

• Supply Chain Standardization
  Suppliers and users of textile machinery accessories benefit from the standard’s clear specifications, improving procurement efficiency and reducing mismatches.

Related Standards

ISO 441:1997 complements other textile machinery and accessory standards by defining essential component requirements that integrate with broader weaving machine systems. Relevant related standards include:

• ISO 838: Textile Machinery – Cylindrical Dobby Cards
  Defines components for fabric control related to weaving process automation.

• ISO 1779: Textile Machinery – Warp Stop Motions for Weaving Machines
  Covers functional aspects of warp stop motions beyond drop wires, including sensor types and actuation.

• ISO 1962: Textile Machinery – Designation of Warp Stop Motion Components
  Provides systematic naming conventions related to warp stop parts coordination.

By adhering to ISO 441:1997, textile machinery manufacturers and users ensure compatibility, improve operational reliability, and maintain international quality benchmarks for drop wires in warp stop motions without automatic drawing-in. This fosters enhanced performance and standardization within the global textile manufacturing sector.