Constant-Length Drive Struts for Cross Slide Positioning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Machine tools require complex measuring systems for precise positioning of the second slide element, which is inefficient and prone to errors.

Innovation Solution

The use of four drive struts forming two drive groups with non-parallel struts to determine the position of the movable carriage element, combined with a common guide track for guide carriages to enhance torsional rigidity and precision, allowing for precise positioning by blocking specific movements and using a measuring system to detect relative positions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If complex measuring systems are used for positioning the second slide element, then positioning precision is improved, but device complexity increases

Engineering Contradiction:
Improvepositioning precisionVSAvoidmeasuring system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical measuring systems with a geometrically determined positioning mechanism. Four drive struts with constant lengths form a quadrilateral linkage that mechanically constrains the second slide element to specific positions based on the strut lengths and guide track geometry, eliminating the need for complex electronic measuring and control systems.

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

Solution Approach 2:

The invention uses the constant length parameter of the four drive struts as a geometric constraint to determine the position of the second slide element. By maintaining fixed strut lengths and using them as rigid constraints in the quadrilateral linkage, the system achieves precise positioning through geometric parameters rather than active measurement.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If four drive struts forming two drive groups are used to determine position, then positioning precision is improved, but device complexity increases

Engineering Contradiction:
Improvepositioning precisionVSAvoiddrive mechanism complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The positioning mechanism is segmented into two drive groups, each consisting of two non-parallel drive struts. Each drive group independently determines a line of position for the second slide element, and the intersection of these lines from both groups provides the precise position. This segmentation creates a redundant geometric constraint system that enhances precision.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent combines multiple positioning constraints from four drive struts into a unified geometric system. The two drive groups work together to simultaneously constrain the position of the second slide element, merging individual strut constraints into a cohesive positioning mechanism that achieves high precision through geometric intersection.

Inventive Principle:
Principle #5Merging (Combining)

3Area of stationary object

If guide carriages are guided on a common guide track, then space requirement is reduced, but manufacturing precision requirements increase

Engineering Contradiction:
Improvespace requirementVSAvoidguide track precision
Core Design Contradiction:
Area of stationary objectVSManufacturing precision

Solution Approach 1:

The common guide track serves multiple functions: it guides all four guide carriages, provides a reference geometry for positioning, and establishes the spatial relationships between drive struts. This multi-functional use of a single guide track reduces the overall space requirement while the precision is maintained through the geometric constraints of the constant-length struts.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP1759809B1Machine tool with a cross slide movable by means of actuating rods of constant length.
Publication Date: 2010.10.27 INDEX WERKE GMBH & CO KG HAHN & TESSKY
  • EP1759809B1 patent drawingFigure 1
  • EP1759809B1 patent drawingFigure 2
  • EP1759809B1 patent drawingFigure 3

AI summary

Four drive struts of invariant length, each with pivot joint, act on secondary slide element of compound slide system. Each of the struts is pivotally connected to guiding slide, which is guided in linearly movable manner transversely in relation to longitudinal direction of the respective drive struts. At least two of the drive struts run parallel to one another.