Gewindeschneidmaschine

摘要

1,080,522. Screw-cutting lathes. CRI-DAN. May 25, 1965 [June 24, 1964], No. 22106/65. Heading B3T. A screw cutting lathe comprises a headstock 8, Fig. 6, a tool holder 5 carried by a transverse carriage 6, mounted on a longitudinal carriage 10, movable on a slide 9, slidable on a bed 7, the tool 4 being moved in the cycle as shown in Fig. 2 when external screwing, or as shown in Fig. 5 when internal screwing, by cam means driven from the work spindle. For external screw cutting the tool is arranged as shown in Fig. 1, and for internal screw cutting the tool is arranged as shown in Fig. 4. Cams 17, 18, 19 and 24 are driven by a shaft 11, cam 17 providing the longitudinal movements of the tool, cams 18, 24 providing the transverse movements of the tool, and cam 19 providing the depth of cut of the tool. Carriage 6 carries spring urged end stops 67, 68, Fig. 10, which are adapted to engage the ends of a nut 73, the latter having a screw 71 screwed therein. Screw 71 is screwed into or out of nut 73 so that carriage 6 is spring- urged in the direction F or F1, Fig. 6, depending on whether an internal or an external thread is to be cut. A lever 27 is pivoted to slide 9 at 28, and due to the urging of carriage 6 in direction F or F1, rollers 26 or 261 engage projection 25 or 251 on cam 24. Cam 24 is oscillated to rock lever 27 so as to move carriage 6 transversely, by an adjustable lever 23, a lever 21, and cam 18, and tool 4 is moved towards the work at the beginning of the cycle, and away from the work at the end of the cycle. Cam 24 is carried on an eccentric 31, Fig. 9, and a ratchet wheel 54 integral with the eccentric is actuated by a pawl 36 operated by cam 19, to provide the depth of cut. To perform the cycle according to Figs. 1 and 2 a reference mark 60 on eccentric 31 is placed opposite a mark 58, and to perform the cycle of Figs. 4 and 5 mark 60 is placed opposite a mark 59. In a modification, a double eccentric is provided. Lever 27 carries a shoe 29 which slides in a channel 30 in carriage 6, Figs. 9 and 10, and the channel is integral with a pivot pin 64. The channel can be set parallel to the machine axis for cutting cylindrical threads, or can be included thereto for cutting conical threads.