Multi-lobed Pneumatic Piston for Adjustable Collet Chuck
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current adjustable barrels are inadequate for guiding bars with diameters greater than one inch, as standard pneumatic pistons lack sufficient operating force, and hydraulic variants are costly and complex, while existing solutions fail to accommodate bars with varying diameters within the constraints of machine tool space.
Innovation Solution
An adjustable barrel with a multi-lobed pneumatic piston that increases the radial surface area for pressure application, allowing for higher clamping forces in a compact space, eliminating the need for hydraulic systems and enabling operation with bars up to 32 mm diameter.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a standard pneumatic piston is used, then the device is simple and compact, but the clamping force is insufficient for bars greater than one inch diameter
Solution Approach 1:
The piston wall is designed with a multi-lobed shape instead of a simple cylindrical form. This geometric transformation increases the radial surface area of the piston, allowing greater pressure application area and thus generating higher clamping forces while maintaining the same pneumatic pressure and compact footprint.
Solution Approach 2:
The invention changes the geometric parameters of the piston structure by introducing lobes with varying radial thickness. This modifies the pressure distribution and total force output without changing the fundamental pneumatic operation or requiring higher system pressure.
2Force
If a hydraulic system is used to increase clamping force, then sufficient force is achieved, but the device becomes more complex and costly
Solution Approach 1:
The invention maintains the simplicity of pneumatic systems while achieving hydraulic-level forces through the multi-lobed piston geometry. The pneumatic pressure acts on the increased radial surface area of the lobes, generating sufficient clamping force without requiring hydraulic fluid, pumps, or complex sealing systems.
Solution Approach 2:
By modifying the piston's geometric parameters (adding lobes, increasing radial surface area), the system achieves higher force output from the same pneumatic pressure source, eliminating the need for hydraulic systems while maintaining force requirements.
3Force
If the piston surface area is increased to generate higher clamping force, then more force is available, but the device size increases beyond available machine tool space
Solution Approach 1:
The multi-lobed piston design increases the radial surface area without increasing the axial length or outer diameter of the piston. The lobes create additional surface area within the existing cylindrical envelope, allowing higher force generation within the same volume constraints.
Solution Approach 2:
The lobes are arranged within the circular footprint of the piston, effectively nesting the increased surface area within the existing boundary. This allows the piston to generate higher forces while fitting within the same space allocation in the machine tool.
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 high clamping forces suitable for larger diameters, is cost-effective, and simplifies assembly/disassembly, while maintaining compactness and operational efficiency within existing machine tool dimensions.
Implementation Method 1
a pneumatic piston located at least partially in the main body, for pneumatically tightening and/or loosening the material in the gripper
Implementation Method 2
the wall is multi-lobed in shape such that the radial thickness of the wall, in a plane perpendicular to the longitudinal axis, is not constant... increasing the surface of the piston, thus generating, with a usual pneumatic pressure, a sufficient axial clamping force
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The barrel has a biconical grip located partially in a main body i.e. sheath, to tighten and/or loosen a material i.e. bar. A single-piece piston (105) is located partially in the body to pneumatically tighten and/or loosen the material. The piston has a base (202) and a separation wall (204) extending radially from the base. The wall transversely separates chambers located axially in the barrel with respect to a longitudinal axis of the barrel. The wall comprises a shape of lobes (201), so that radial thickness of the wall, in a plane perpendicular relative to the axis, is not constant. : The lobes have round, square or triangular shape. USE : Adjustable barrel for use with/in a machine tool to guide a to-be machined material i.e. bar, along a longitudinal axis of the barrel. ADVANTAGE : The barrel can be operated with lower quality bars so as to increase a surface of the piston, and to generate, with usual pneumatic pressure, sufficient axial tightening force in an encumbrance limited in dimensions, thus increasing gripping force in a reduced or limited encumbrance. The barrel has high compactness-tightening force ratio. The barrel is capable of guiding bars of different diameter. DESCRIPTION OF DRAWINGS : The drawing shows a perspective view of a piston with lobes. 105 : Single-piece pneumatic piston 201 : Lobes 202 : Base 203 : Grooves 204 : Separating wall.