GB1497562A - Machine tool control - Google Patents

Abstract

1497562 Machine tool control A TACK 12 March 1976 [25 Feb 1975] 7846/75 Heading G3N A control device for a machine tool computes feed increments for successive passes by forming a mathematical combination of a stored feed increment and a constant. The constant can be subtracted from the increment to give a series of corrected increments forming an arithmetic progression or the constant and increment can be multiplied, the constant being less than one, to give a series of corrected increments plotted as a decreasing exponential curve. The increment and constant are stored in analog or digital form and can be manually set on a panel Fig. 3 (not shown) with an LED display 29. Digital stores 31, 32, 33 receive the total, increment and constant from switches 21, 22, 23 on the panel. A signal appears on line 34 at the end of a machining pass to multiply the increment by the constant, the product in accumulator 35 being written back in store 32 as the new increment. The product is also subtracted from the total feed 31. The machine tool can be a relieving, screw cutting or grinding lathe, a milling or a grinding machine, and tool drive is effected by a stepping motor controlled by pulses from gate 40 until comparator 43 indicates that the increment in accumulator 35 has been reached. The angle of the cut α Fig. 1 (not shown) is set via switch 26 in store 44 and this controls the X, Z feed directions.