GB604606A - Improvements in and relating to suction chucks - Google Patents

Abstract

604,606. Suction chucks. ERIKSSON, E. O. Sept. 24, 1945, No. 24728. [A Specification was laid open to inspection under Sect. 91 of the Acts, March 23, 1946.] [Class 60] In a suction chuck, for lathes and other machine tools, having a member spring-pressed in a direction to cause the reduction of pressure necessary to hold the work, movement of the member in the opposite direction against the spring pressure is effected by fluid pressure. The work-receiving plate 3 has a duct 5 leading to the interior of bellows 8 connected to the plate 3 and to a piston 7 urged rearwardly by a spring 9. When compressed air is admitted to the rear face of the piston, this is moved forwardly against the spring pressure to expel air from the bellows through the duct 5; air is also expelled through the duct 10. The work is then placed in position and the rear face of the piston is connected to atmosphere. The spring 9 then urges the piston rearwardly creating the necessary suction to retain the work. The bellows 8 preferably comprises metal discs having a small central hole and welded together alternately at their outer and inner edges. The bellows may be omitted, the piston then being provided with packings between it and the body of the chuck; the duct 10 is also omitted. A packing ring 11 of rubber or other suitable material is inserted in a recess in the work-receiving plate 3; a number of concentric recesses may be provided, a packing ring being inserted in the recess appropriate for the size of the article to be chucked. For holding annular objects, the disc 3 has two concentric recesses with packing rings and the suction duct communicates with the annular space between the recesses. For holding objects with an irregular surface, the disc 3 may have a correspondingly shaped contact surface. The Specification as open to inspection under Sect. 91 states that the forward movement of the piston 7 against the spring pressure may be effected mechanically, electrically or electromagnetically. Alternatively, the disc 7 may be fixed to the body 1, and the disc 3 moved axially by pressing the work against it; the space between the discs 3 and 7 communicates with the atmosphere through a check valve. Alternatively, the piston 7 and bellows 8 may be omitted, the duct 5 communicating directly with a source of vacuum. This subject-matter does not appear in the Specification as accepted.