Clamp Device Compression Coil Spring Nesting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing clamping apparatuses require strict dimensional control due to high spring constant conical disc springs, leading to increased machining costs and susceptibility to foreign matter intrusion with larger sizes of compression coil springs.

Innovation Solution

A clamping apparatus using a compression coil spring positioned inside the housing, eliminating the need for space between the sleeve and housing, allowing a larger descending stroke with reduced height and enhanced rigidity, and preventing foreign matter intrusion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If a conical disc spring is used to urge the sleeve upward, then the sleeve can be held at a raised position with sufficient force, but the spring constant is large which necessitates a small descending stroke, requiring strict dimensional control and increasing machining costs

Engineering Contradiction:
Improveurging force of springVSAvoiddimensional control
Core Design Contradiction:
ForceVSManufacturing precision

Solution Approach 1:

The patent changes the spring parameter (spring constant) by switching from a conical disc spring with high spring constant to a compression coil spring with lower spring constant. This allows the sleeve to have a larger descending stroke while still providing sufficient urging force, thereby reducing the need for strict dimensional control of components.

Inventive Principle:
Principle #35Parameter changes

2Length of moving object

If a compression coil spring is used instead of a conical disc spring to achieve a larger descending stroke, then the spring constant is smaller allowing larger stroke, but the total size becomes larger making the apparatus taller and susceptible to foreign matter intrusion

Engineering Contradiction:
Improvedescending strokeVSAvoidforeign matter intrusion
Core Design Contradiction:
Length of moving objectVSObject-affected harmful factors

Solution Approach 1:

The patent applies the nesting principle by placing the compression coil spring inside the hollow cylindrical body of the plug portion. The spring is positioned within the internal cavity of the plug, nested within the existing structure. This containment approach prevents foreign matter intrusion while maintaining the larger descending stroke capability of the compression coil spring.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Length of moving object

If the spring size is increased to provide larger descending stroke, then the stroke increases, but the height of the clamping apparatus becomes taller

Engineering Contradiction:
Improvedescending strokeVSAvoidheight of apparatus
Core Design Contradiction:
Length of moving objectVSLength of stationary object

Solution Approach 1:

The patent resolves the height conflict by changing the spatial dimension where the spring operates. Instead of extending the spring vertically outward (which would increase apparatus height), the spring is positioned horizontally within the internal cavity of the plug portion. This dimensional repositioning allows the spring to provide the necessary urging force and enable larger descending stroke without increasing the overall height of the clamping apparatus.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 provides a larger descending stroke with reduced height, improved rigidity, and protection from foreign matter, enhancing the clamping apparatus's operational efficiency and reliability.

Implementation Method 1

An advancing spring A constituted by a compression coil spring is arranged below the pushing member 56, and the advancing spring A urges the sleeve 28 upward through the pushing member 56 with a predetermined force.

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

the tapered hole provided in the movable block causes the sleeve, which is held at a raised position by an urging force of the coned disc spring, to contract diametrically

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP2489464B1Clamp device
Publication Date: 2013.12.04 KOSMEK LTD (JP)
  • EP2489464B1 patent drawingFigure 1

AI summary

Above and below a piston (15) inserted into a housing (5), there are respectively provided a lock chamber (16) and a release chamber (17) where compressed air is supplied and discharged. A diametrically expandable and contractible tapered sleeve (28) is attached between an annular plug portion (26) projected upward from the housing (5) and a tapered hole (11) provided in a work pallet (2). An output rod (35) inserted into a cylindrical hole (26a) of the plug portion (26) is connected to the piston (15). Lock springs (49) constituted by compression coil springs are respectively inserted into a plurality of spring-attachment holes (48) formed in a recessed manner in an upper wall (16a) of the lock chamber (16). The spring-attachment holes (48) are communicatively connected to an outer surface of the housing (5) by through holes (55), respectively, and pushing members (56) are hermetically inserted into the through holes (55). The lock springs (49) urge the sleeve (28) through the pushing members (56) with a predetermined force.