Loader Servo Torque Control for Accurate Workpiece Positioning

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Manual setup of machine axis and loader axis positions in machine tools can lead to servo faults due to misalignment of workpieces, causing mechanical forces that interfere with the proper functioning of loader mechanisms.

Innovation Solution

Reducing the electric current to the linear and rotary servo motors of the loader mechanism to minimize torque, allowing the mechanism to adjust and neutralize forces, thereby determining proper workpiece positioning without causing servo faults.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the loader mechanism operates at full power with high torque, then loading and unloading operations are efficient and productive, but misalignment forces from workpiece self-centering cause servo faults and operational failures

Engineering Contradiction:

Improveloading and unloading efficiencyVSAvoidservo fault prevention

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies dynamics by making the loader mechanism's torque output variable rather than fixed. The control system dynamically adjusts the torque based on operational phase: high torque during normal loading/unloading for productivity, and reduced torque during positioning operations to allow workpiece self-centering forces to align the loader axis with the machine tool axis without causing servo faults.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the torque parameter of the loader mechanism from a constant full-power value to a variable parameter. By modifying the current supplied to the servo motor, the system transitions between high-torque mode for efficient operation and low-torque mode for precise positioning, resolving the contradiction between productivity and reliability.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If the loader axis is manually positioned to align with the machine tool axis, then proper functioning is achieved, but workpiece self-centering forces create mechanical conflicts and servo faults

Engineering Contradiction:

Improveaxis alignment accuracyVSAvoidservo fault occurrence

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent inverts the traditional approach by not manually positioning the loader axis to match the machine tool axis. Instead, it allows the workpiece self-centering forces to naturally align the axes, and uses reduced torque to accommodate this self-alignment process, preventing servo faults that would result from rigid manual positioning.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The system uses the workpiece's own self-centering forces to achieve alignment between the loader axis and machine tool axis. By reducing torque during positioning, the loader mechanism allows these inherent workpiece forces to perform the alignment function, eliminating the need for manual positioning and preventing the mechanical conflicts that arise from rigid alignment.

Inventive Principle:

Principle #25Self-service

3Reliability

If reduced torque is applied to the loader mechanism, then workpiece self-centering forces can neutralize mechanical conflicts and improve alignment, but loading and unloading operational efficiency decreases

Engineering Contradiction:

Improveservo fault preventionVSAvoidloading and unloading efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent applies periodic action by alternating between two torque modes: reduced torque during positioning operations to prevent servo faults and ensure proper alignment, then full power torque during loading and unloading operations to maintain productivity. The control system cycles between these states based on operational requirements, resolving the efficiency-loss concern while maintaining reliability.

Inventive Principle:

Principle #19Periodic action

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 accurate workpiece positioning by neutralizing mechanical forces, allowing for proper centering and alignment, reducing the risk of servo faults and enabling efficient loading and unloading operations at full power.

Implementation Method 1

a linear drive means and a rotary drive means, each having a reduced full power amount of torque

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS11986918B2Method of positioning a workpiece on a machine tool

Publication Date: 2024.05.21 THE GLEASON WORKS

AI summary

A method wherein by reducing the amount of current, and therefore torque, to the linear servo motor (50) and/or rotary servo motor (52) of a loader mechanism (9), the loader mechanism is operable for determining proper workpiece positioning in a machine tool such as a gear manufacturing machine, particularly a machine (4) for manufacturing bevel and hypoid gears.