Self-Centring Workpiece Locking for Single-Station Machining

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current machining processes require two separate stations to lock and machine mechanical parts, leading to high costs, long lead times, limited precision, and additional operations for gripping surfaces, which increases time and tool wear.

Innovation Solution

A device using a hydraulic cylinder with a first piston and self-centring locking elements allows for single-station machining by aligning the mechanical part's cavity with the machine tool's axis, enabling precise locking and machining without the need for additional gripping surfaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If two different stations are used to machine a single piece, then the workpiece can be locked and machined at different points, but the machining costs increase and lead times are extended

Engineering Contradiction:
Improveworkpiece locking capabilityVSAvoidmachining efficiency
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent merges the functions of two separate work stations into a single station by providing a restraint device that can lock the workpiece at multiple points simultaneously. The restraint device includes multiple locking points that can secure the workpiece in position, eliminating the need to transfer the workpiece between stations while maintaining the same locking and machining capabilities.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The restraint device is designed to perform multiple functions within a single work station: it can lock the workpiece at multiple points, provide stable support during machining, and enable operations that would otherwise require separate stations. This multi-functional approach maintains adaptability while improving productivity.

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

2Adaptability or versatility

If two different stations are used to machine a single piece, then different locking points can be used, but the precision is limited by alignment issues between stations

Engineering Contradiction:
Improvelocking point configurationVSAvoidmachining precision
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

By combining multiple locking points into a single restraint device at one work station, the patent eliminates alignment issues between separate stations. The workpiece is locked in a fixed position relative to the machine tool's reference system, ensuring that all machining operations are performed with consistent precision without the need for repositioning or realignment.

Inventive Principle:
Principle #5Merging (Combining)

3Ease of manufacture

If the second station grasps the workpiece at different points, then machining can be completed, but additional gripping surfaces are required which increase operations and tool wear

Engineering Contradiction:
Improvemachining completion capabilityVSAvoidgripping surface requirements
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The restraint device combines multiple gripping functions into a single device that secures the workpiece at multiple points simultaneously. This eliminates the need for separate gripping surfaces and operations, as the workpiece can be locked and machined in place using the same restraint device throughout the entire machining process.

Inventive Principle:
Principle #5Merging (Combining)

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

This solution reduces machining costs and time, improves precision, and eliminates the need for additional operations, enabling complete machining on a single machine tool without the limitations of dual stations.

Implementation Method 1

a first piston (9) movable inside the hydraulic cylinder (2) due to the effect of a pressurised hydraulic fluid along a main line (B1)

Methodology Applied
Scientific EffectHydraulic pressure: Hydraulic Press

Implementation Method 2

at least two self-centring locking elements (18) associated with the head (10) in a movable manner along sliding lines (B2) for abutting an inner surface (S) of the cavity (C)

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3849744B1Device for restraining/locking mechanical parts on machine tools
Publication Date: 2023.09.06 HYDROBLOCK
  • EP3849744B1 patent drawingFigure 1
  • EP3849744B1 patent drawingFigure 2
  • EP3849744B1 patent drawingFigure 3

AI summary

The device (1) for restraining/locking mechanical parts on machines tools comprises: a hydraulic cylinder (2); a first piston (9) comprising a head (10) which projects from the hydraulic cylinder (2), the first piston (9) being slidable along a main line (B1); at least two self-centring locking elements (19) joined to the head (10) in such a way that they are movable along lines of sliding (B2) which are substantially transversal to the main line (B1); and movement means (21, 22) for moving the self-centring locking elements (19) between a retracted position and an extracted position, wherein the movement means (21, 22) comprise: a hydraulic chamber (21) made in the first piston (9); a second piston (22) which is slidable along the main line (B1) between a starting position and an arrival position and which comprises an operating portion (23) joined to the self-centring locking elements (19).