What Is a Parallel Chuck?
A parallel chuck is a type of chuck with a parallel open/close mechanism, primarily used for workpiece transfer.
The parallel chuck grips the workpiece at the center, functioning similarly to a three-jaw scroll chuck used in machine tools such as machining centers and CNC lathes, but it is essentially a two-jaw structure, resulting in a more compact design.
As hand jaws can be attached to the fingers to match the shape of the workpiece, the chuck is highly versatile.
Uses of Parallel Chucks
Parallel chucks are commonly used in workpiece transfer machines due to their lightweight and compact features. They are often used in loader machines connected to machine tools for supplying workpieces. Their low weight makes them suitable for high-speed loaders with strict maximum weight restrictions.
The shape of workpieces that can be gripped depends on the stroke of the fingers and the hand jaws to be installed, but cylindrical shaft material is typically suitable.
Principles of Parallel Chucks
Generally, parallel chucks operate using compressed air supplied from an air compressor. An air cylinder is built inside the chucks, and the air cylinder is mechanically connected to the fingers via driving rollers. When air is supplied from the air supply port, the piston of the air cylinder is pushed, causing the driving roller to push the fingers closed. A single air supply port is called a “single acting type.”
Some models have multiple air supply ports and are known as “double-acting types.” With the double-action type, the gripping force can be adjusted depending on the air supply port used.
As an air chuck, it tends to have higher repeatability (±0.01 mm or so) compared to hydraulic or manual chucks. However, due to its compact structure, it is less suitable for clamping heavy workpieces.