The cutter location tape contains the absolute coordinates of the centerline of the machine tool and the feedrate as it traverses the part being cut.
If machine tool which is to be controlled has a resolution of u inches and m=0.001/u is an integer, which is the usual case, the frequency of the pulses as well as the number of pulses in the pulse train must be modified. 1111101111) ,24 l 6 q -25 1 11151001111 l I I 31111111 I I a I OUTPUT 1111;.
An oscillator which produces 1,000 m pulses per second is used to pulse a preset counter which is preset to m and therefore, sends 1000 demand pulses per second to cause a new command word to be read from the computer memory every millisecond into an output buffer. 1o l 26 I 1 1 9 1151 001112 I 11111111 I 71117101 1T1.
While this type of system has worked admirably in those applications where the resolution of a machine tool is fairly large as in the order of 0.001 inch, where the resolution of the machine tool is relatively small as, for instance, 0.0001 inch, an excessive amount of core is required and the loading of the processor is quite extensive.
Summary Briefly, there is provided a system and method of providing the correct number of pulses to drive any machine tool having a resolution of 0.001/m (where m is a positive integer), from a standard program written for control of a machine tool having a resolution of 0.00] inch.
The part programmer describes a part to be cut and the manner in which the machine tool should proceed to cut it by.
writing a computer program using, for instance, the APT (Automatic Programmed Tool) language to produce a cutter location tape (CL tape).
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co.
If a command word from the buffer of the computer memory is gated out each millisecond and the standard program is written for a machine tool having a 0.001 inch resolution, a maximum vector feedrate of 60 inches per minute can be provided. 235/151.11X POST J PROCESSOR I[ 1 I/() DEVICES 4 1 I -5 21 29 1 011111111 0011 l PROCESSING STORAGE I UNIT UNIT 1 l I I 11111.
I I 29 CENTRAL CORE l PROCESSING J STORAGE I 1 UNIT v I (INT. K RECEIVE L CHANNEL , TRANSMISS10N= CONTROL MACHINE l 5 CONTROL TOOL I 8 OUTPUT -55 DEMAND PULSE N 43 OSCILLATOR I 26 5 5? i N CHANNEL s n a 5 I I RECEIVE l OUTPUT REG TRANSMISSION L CONTROL L MACHINE 1 CONTROL mm I DEMAND PULSE N 44 OSCILLATOR- 4N PRESET N40 COUNTER 42 i l INVENTUR. 697,849, there is described a system for controlling a machine tool in which a demand oscillator is used to gate previously calculated command words from a core storage unit to the servos of the machine tool.
a 2 JACK ROSENBERG ATTORNEY SYSTEM FOR ACCOMMODATING VARIOUS MACHINE TOOL RESOLUTIONS FROM A STANDARD PROGRAM BACKGROUND OF INVENTION 1. In this system the frequency of the demand oscillator is set such that if a one bit is contained in the same bit position of each command word, the machine tool will move at its maximum feedrate.
 SYSTEM FOR ACCOMMODATING VARIOUS MA- CHINE TOOL RESOLUTIONS FROM A STANDARD Primary Examiner-Malcolm A. Command words containing control bits for control of the various axes of a machine tool are stored in a computer memory and gated out under control of pulses provided by an oscillator. B23g2l/00, G061 /46  Fieldof Search ..235/l51.1l; 340/1725; 318/18 (20.100)  References Cited UNITED STATES PATENTS 3,069,608 12/1962 Forresteretal. 235/l5l.11X 3,430,036 2/1969 Patrick 235/151.1l 3,465,298 9/1969 La Dukeetal.