GB843397A - Improvements in control of tools and other movable parts in automatic lathes - Google Patents

Abstract

843,397. Turning; drilling. SCHUTTE, A. H., COMMER, G., WELCKER, L., THEN, E., and PECHMANN, VON E. F., [trading as SCHUTTE, A. H. [Firm of].]. Oct. 12, 1956 [Oct. 15, 1955], No. 31180/56. Class 83 (3). [Also in Group XXIX] A machine-tool comprises a movable part 56, Fig. 4, controlled by cams, levers 18, &c., Fig. 1, through columns of pressure-oil 25, 26, between a control-piston 29, Fig. 2, and a working piston 53, the two columns working in opposition to one another and being connected to spring- loaded pistons 59. A lathe has a turret containing four work-spindles 11 having feed and work-holding collets operated by pistons 34, 33, respectively. Axially-traversed tool-slides 13, 14, and forming-tool-slides 15, 16, are operated by levers 18, 19, 22. Each lever, such as 18, is connected by a rod 32 to a piston 29 carrying rack-teeth engaging a pinion 31 meshing with a balancing-piston 30. The fluid displaced from and towards the oppositely-moving pistons passes along the lines 25, 26, to the pistons 33, 34. A similar transmission occurs between each lever 19 and a piston 38, Fig. 3, in a cylinder 35 for controlling the tool-slides 13, 14. The slide 14 carries a drill 47 rotated by a shaft 48, and is engaged by a nut 43 on the cylinder 35. Rotation of the nut enables the position of a depthstop 46 on the piston 38 to be adjusted. The depth-of-drilling can also be adjusted by rotating the piston 38, which is screw-threaded into the lathe framing. Attached to a further slide 56, which is the slide controlled according to the invention, is a piston-rod 54 adjustable against scales 57, 57a. When pressure-fluid is forced into the line 25 by a piston 29 (as in Fig. 2), the slide 56 is moved against a stop 62. There is then a slight over-travel of the piston 29, which moves a piston 59 a distance determined by the pressure of a spring 60 adjusted by a nut 61. If the slide 56 does not reach the stop 62 due to a blunt tool &c., the piston 59 is moved further to illuminate a warning light 53a and actuate a switch 96, to stop a part or the whole of the machine. The initial slight movement of the piston 59 takes up small fluid losses. If greater losses occur, the piston 59 moves sufficiently to allow a passage 67 therein to overlap a passage 66 to permit extra fluid to be supplied by a piston 64 engaged by a spring 65. If there is excess fluid, it passes out of the passage 67 into a duct 58a. A similar arrangement 58 is included in the line 26. Fluid may be supplied along a line 63c. If excessive losses occur in the system, the piston 64 actuates a switch 63a to stop the machine and illuminate a warning light 63b. Specification 843,396 is referred to.