Snap-Fit Tool Clamping for Miniaturized Torque Transmission

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing tool clamping systems in machine tools face challenges in miniaturization while maintaining concentricity and torque transmission, and are complex for automated tool changes.

Innovation Solution

A snap-fit connection between metallic shaft sections using a locking pin and locking sleeve, facilitated by a pivoting movement, achieves concentricity and torque transmission without separate clamping devices, allowing automated connection and disconnection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If a complex clamping mechanism with separate drive and rotating components is used, then torque transmission and concentricity are maintained, but miniaturization becomes difficult and device complexity increases

Engineering Contradiction:
Improvesize of clamping systemVSAvoidcomplexity of clamping mechanism
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The locking pin and locking sleeve are integrated directly into the shaft sections themselves, merging the clamping function with the shaft structure. This eliminates separate clamping devices and rotating components, enabling miniaturization while maintaining torque transmission capability through the elastic snap-fit connection between the locking elements

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention extracts and eliminates unnecessary rotating components and separate clamping devices from the system. Only the essential locking pin and locking sleeve remain, which are integrated into the shaft sections. This reduction of components directly enables miniaturization while simplifying the overall device structure

Inventive Principle:
Principle #2Taking out (Extraction)

2Extent of automation

If additional drives are added for automated tool changes, then automation capability is improved, but device complexity and cost increase

Engineering Contradiction:
Improveautomation of tool changesVSAvoidnumber of additional drives
Core Design Contradiction:
Extent of automationVSDevice complexity

Solution Approach 1:

The locking pin and locking sleeve are designed to automatically engage and disengage through their elastic snap-fit connection. The locking elements self-lock when the shaft sections are joined and self-release when separated, eliminating the need for additional drives or complex actuation mechanisms for automated tool changes

Inventive Principle:
Principle #25Self-service

3Manufacturing precision

If metallic shaft sections with elastic properties are used for snap-fit connection, then miniaturization is enabled and concentricity is improved, but torque transmission capability may be reduced

Engineering Contradiction:
Improveconcentricity of shaft connectionVSAvoidtorque transmission capacity
Core Design Contradiction:
Manufacturing precisionVSStrength

Solution Approach 1:

The locking pin and locking sleeve are designed with precise curved surfaces that engage in a snap-fit connection. The elastic deformation of these curved surfaces during engagement creates a positive locking action that maintains high concentricity while transmitting torque through the elastic-re塑性 deformation cycle of the locking elements

Inventive Principle:
Principle #14Spheroidality (Curvature)

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

The solution enables miniaturized tool clamping with high concentricity and torque transmission, simplifying automation by eliminating the need for additional drives and ensuring reliable, vibration-resistant connections.

Implementation Method 1

at least one detent (9a-c) is provided on the circumference of the locking pin (5), which, during the locking pivot, engages at least one corresponding counter-detent (10a-c) on the locking sleeve (6) with elastic deformation of the locking pin (5) and/or locking sleeve (6)

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3302856B1Tool clamping system
Publication Date: 2022.10.05 BROETJE AUTOMATION
  • EP3302856B1 patent drawingFigure 1
  • EP3302856B1 patent drawingFigure 2a~2b
  • EP3302856B1 patent drawingFigure 3a~3b

AI summary

The invention relates to a tool clamping system (2) having two metal shaft portions (3, 4), wherein the first shaft portion (3) has a locking pin (5) at its end and the second shaft portion (4) has a locking sleeve (6) at its end, wherein, in order to produce a releasable drive-related connection, the first shaft portion (3) is able to be introduced coaxially with its locking pin (5) into the locking sleeve (6) of the second shaft portion (4), and the two shaft portions (3, 4) are pivotable with respect to one another into a locking pivoted position by way of a locking pivoting movement (7) about a common geometric longitudinal axis (8), wherein at least one latching formation (9a-c) arranged on the circumference of the locking pin (5), preferably at least three latching formations (9a-c) distributed around the circumference of the locking pin (5), snaps or snap over at least one corresponding mating latching formation (10a-c) on the locking sleeve (6), preferably over at least three corresponding mating latching formations (10a-c) on the locking sleeve (6), during the locking pivoting movement, with elastic deformation of the locking pin (5) and/or locking sleeve (6).