Parallelspannfutter

A Parallelspannfutter, often translated as a parallel jaw chuck or universal chuck, is a workholding device used in machining operations. Its primary function is to securely grip and hold a workpiece during operations such as turning, milling, or grinding. The defining characteristic of a parallelspannfutter is that its jaws move parallel to each other, ensuring that the workpiece remains centered and stable. This parallel movement is typically achieved through a scroll plate mechanism, which is actuated by a wrench or handwheel. As the scroll plate rotates, it engages with angled slots on the back of the jaws, causing them to move inwards or outwards in unison.

Parallelspannfutters are commonly found in two main types: manual and hydraulic. Manual versions are operated by hand, while hydraulic models utilize hydraulic pressure to actuate the jaws, offering greater clamping force and precision, especially for heavier workpieces or high-speed operations. They can be equipped with two, three, or four jaws, with three-jaw chucks being the most prevalent due to their self-centering capabilities, which is advantageous for holding cylindrical or hexagonal workpieces. Four-jaw chucks offer independent jaw adjustment, providing greater flexibility for irregularly shaped or off-center components. The jaws themselves are often reversible, allowing for internal or external gripping of the workpiece. Regular maintenance, including lubrication and cleaning, is essential to ensure the longevity and accuracy of a parallelspannfutter.