Plastic sleeve grips tools at lower cost than oil

Problem:. To meet these needs hydraulic chucks use oil pressure to force in the sides of a clamping sleeve to grip tools. Hydraulic pressure is applied by turning a grub screw, which pushes in a piston. The only problems are that these devices are relatively expensive, and are quite difficult to repair. Solution: Schunk has developed and patented a tool holder that replaces the hydraulic oil round the bush with an elastomeric plastic. Tightening is achieved by using a 'C' spanner to turn the body of the device, so that it moves inwards on a screw thread, axially compressing the plastic sleeve. As a result the plastic sleeve expands inwards, pressing on the outside of the expansion bush in the same way as oil in the hydraulic version. According to Steve Cox of Schunk Intec, The new design, designated, 'Sino-T', is easier to make, easier to repair, and sells for substantially less than the hydraulic version. An added advantage of the use of elastomeric plastic is that it damps machine vibrations, enhancing tool and machine spindle lives, reducing noise, and improving surface finish. Applications: Tool holders are available for spindles SK40 to DIN 69871 AD/B and MAS-BT40 to JIS B6339 and HSK-A63. Tool shaft diameters are 12mm and 20mm. Intermediate bushes are available for 6, 8, 10, 12, and 16mm diameter tool shafts. TS Schunk Intec