GB793473A - Device for control of feed mechanisms in machine tools - Google Patents

Abstract

793,473. Machine-tool details. WERNER, H. H., and RUDIGER, F., [trading as WOHLENBERG KOMM-GES., H.]. Dec. 9, 1955 [Dec. 13, 1954; Feb. 7, 1955], No. 35377/55. Class 83 (3). [Also in Groups XXIV XL (b)] A machine-tool comprises a counter having a pulse-transmitter 10, whose pulses are a measure of the amount of feed of a feed-element 38, an electronic-register 40, a digital entry registersetting means 21, and means by which the register emits an impulse after the preselected number of pulses to stop the feed. The rotation of the feed-screw 37 is measured by the number of pulses received by a photo-cell 11. The register 40 is set by a punched-card, or by the keyboard 21, the keys of which are illuminated when depressed. After a predetermined number of pulses prior to the stopping of the feed, the register acts to slow down the feedmotor 48, and a counter 43 then takes over and finally actuates the relay 45 to operate a prestressed and electromagnetically - operated spring brake to stop the element 38 and disengage the feed. Thus before the element is stopped, an electromagnet 213, Fig. 8, is actuated to stress a spring 215 attached to a lever 209. When, subsequently, an electromagnet 211 is operated to release a catch 210, the lever 209 is suddenly moved to release a friction-clutch 205, 204 and engage a frictionbrake 204, 212. Alternatively, the counter 43 may be replaced by an interselector which resets the register 40 for the remaining predetermined number of pulses. Since the machineelement will not stop dead, the counter may stop the feed before the full number of pulses have been received. In operation by punchedcard, the holes in the card may allow the ends of levers to be drawn therethrough by an electromagnet to operate the keys or separate contacts. Fig. 6 illustrates how a punched-card may be used for controlling the movements of the turret. in a lathe. The card may also include holes for governing the spindle-speed, rate-of-feed, change-of-stock, or for switching to another control. In a modification, there is an initial fast-feed actuated by every other pulse, followed by a slow-feed actuated by each pulse, thus giving a finer sub-division of the feed-movement.. Specification 777,092 is referred to.