GB1440898A - Devices for machining cylindrical and tapered holes - Google Patents

Abstract

1440898 Grinding KUIBYSHEV ZAVOD KOORDINATNO - RASTOCHNYKH STANKOV 4 Feb 1974 05036/74 Heading B3D A device for machining cylindrical and tapered holes comprises a rotating tool 18, such as a grinding wheel, which effects a planetary movement and reciprocates along the axis D-D of the planetary movement, the tool being mounted on a carriage 15, 16 linked to a pusher 42 rotatable with the carriage and movable along the axis for imparting radial feed to the carriage by a drive from a member 35 having a master from which can be set at various angles to the axis, the member engaging a rod 33 reciprocatable along the axis with the carriage and movable by the member perpendicular to the axis, the rod being linked to the pusher member so that the movement of the rod perpendicular to the axis causes movement of the pusher along the axis. The device may be an integral part of a jig-grinding machine or consist of a separate unit fitted to a jig-boring machine having a rotating and reciprocating spindle. In the former case, the headstock 7 of the machine supports a sleeve 12 vertically reciprocated by a drive from a shaft 21 having a gear 20 engaging a rack 19 formed on the sleeve. The spindle 13 is mounted in the sleeve and rotated by gearing 24, 25 from a splined shaft 26 driven by a mechanical drive or by a manual drive having a gear 27. A nut 29 is rigidly secured to the spindle 13 and engages a hollow screw 30 which is formed with gear teeth 31 engaging a rack in the rod 33. A roller 34 on the rod engages the master form 35 which is adjustable on a member 37, in turn, carried by a rod 41 movable by rack-and-pinion gearing 38, 40 from a drive shaft 39. The pusher 42 is keyed to the spindle 13 and rotatable in but axially locked to the hollow screw 30 so that rotation thereof by movement of the rod 33 displaces the pusher 42 axially of the spindle to cause an inclined surface 44 to act on a follower 46 and cause radial movement of a slide 15 along a guideway on the lower part 14 of the spindle. The grinding wheel 18 is mounted on a spindle 18 carried by a further slide 16 adjustable along slide 15. In operation, slide 16 is adjusted along slide 15, and the master form 35 is adjusted to determine the angle of the tapered hole to be ground, which angle may be zero if a cylindrical hole is required. During reciprocation of the spindle, the master form 35 causes the rod to rotate the screw 30 in the nut 29 and axial reciprocate the pusher 13 which, in turn, radially reciprocates the carriage 15 and grinding tool 18. The master form is laterally moved by the drive to shaft 39 to cause feed of the tool. In another embodiment, the pusher (85, Fig. 7. not shown) is disposed eccentrically of the spindle.