Four-Jaw Collet Chuck Rocker Mechanism for Precise Centering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing chucks face inaccuracies and machining errors due to play between components, leading to inconsistent clamping force and positioning issues, especially when handling workpieces with varying dimensions and contours.
Innovation Solution
The introduction of a rocker mechanism between the drive piston and clamping jaws, with a bolt and transmission pins, allows for precise alignment and clamping without play, utilizing centrifugal weights for additional clamping force and a guide groove to prevent jamming, ensuring accurate positioning and consistent clamping across different workpiece configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If movement play is provided between the coupling ring and drivers to compensate for different distances between clamping jaws and workpiece, then adaptability to different workpiece dimensions is improved, but positioning accuracy and repeat accuracy deteriorate
Solution Approach 1:
A rocker mechanism is introduced as an intermediary component between the drive piston and the clamping jaws. The rocker acts as a mediator that converts the linear movement of the drive piston into radial movement of the clamping jaws through a transmission pin, while compensating for dimensional variations. This intermediary mechanism eliminates the need for movement play in the power flow path, thereby maintaining positioning accuracy while adapting to different workpiece dimensions.
Solution Approach 2:
The rocker mechanism changes the movement parameter from linear axial movement of the drive piston to radial movement of the clamping jaws. By altering the movement direction and type through the rocker's rotation around its axis, the system can accommodate varying distances to different clamping jaws without compromising the precision of the clamping action.
2Adaptability or versatility
If movement play is provided between components in the power flow, then compensation for different clamping jaw distances is improved, but clamping force consistency deteriorates
Solution Approach 1:
The rocker serves as a force transmission intermediary that directly connects the drive piston to the clamping jaws through the transmission pin. This eliminates movement play in the force flow path, ensuring that the clamping force is transmitted consistently and predictably to all clamping jaws regardless of their different distances from the drive piston.
Solution Approach 2:
The rocker rotates around a fixed axis point, creating a curved motion path for the transmission pin. This rotational movement allows the mechanism to accommodate radial variations in distance to different clamping jaws while maintaining a consistent force transmission path, thereby ensuring uniform clamping force application.
3Manufacturing precision
If a rocker with transmission pin is used to eliminate movement play, then positioning accuracy is improved, but device complexity increases
Solution Approach 1:
The clamping mechanism is segmented into distinct functional components: the drive piston for axial movement, the rocker for motion conversion, and the clamping jaws for workpiece contact. This segmentation allows each component to perform its specific function efficiently, with the rocker serving as a simple yet effective motion converter that does not significantly increase overall device complexity.
Solution Approach 2:
Instead of moving the clamping jaws directly along the axial direction from the drive piston, the mechanism inverts the movement direction by using the rocker to convert axial piston movement into radial jaw movement. This inversion simplifies the force transmission path and improves positioning accuracy without requiring complex guiding mechanisms.
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 enables precise, repeatable alignment and clamping of workpieces with varying dimensions, ensuring accurate machining by compensating for differences in distance and time of impact between clamping jaws, thereby improving positioning accuracy and clamping force consistency.
Implementation Method 1
a centrifugal weight is arranged in the chuck body and is mechanically coupled to one of the clamping jaws via a lever... the alignment of the lever produces a centripetal force which acts on the centrifugal weight during the rotation of the chuck body and pushes it outwards. Consequently, the lever is moved in the direction of the longitudinal axis of the chuck body and an additional radial clamping force is produced on the respective clamping jaws.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a chuck (1) by which workpieces (2) are supported in a singulated and centered manner for machining by a machine tool, - with a chuck body (3), - with four clamping jaws (5, 6, 7, 8) radially movable on the chuck body (3), which are arranged in pairs in an X or Y plane, - and with a drive piston (9) axially movable in the chuck body (3), which is coupled to the four clamping jaws (5, 6, 7, 8) via an inclined surface or helical gear (10) machined on the drive piston (9) and the respective clamping jaws (5, 6, 7, 8) and moves them synchronously towards or away from the workpiece (2) to be clamped, so that a positionally accurate, i.e. centered, alignment for a large number of differently designed workpieces (2) can be achieved with high repeatability for subsequent clamping operations.- that a rocker (11) is provided between the drive piston (9) and each pair of adjacent clamping jaws (5, 7 or 6, 8), - that the rocker (11) has a center of symmetry (12) into which a bolt (13) pivotably mounted on the drive piston (9) is inserted, about which the rocker (11) can be pivoted depending on the contact of the clamping jaws (5, 6 or 7, 8) with the workpiece (2), - and that a transmission pin (14, 15) drivenly coupled to the rocker (11) is provided laterally adjacent to the bolt (13), at the end of which opposite the rocker (11) the respective clamping jaw (5, 6, 7 or 8) is mounted and supported.