APPARATUS FOR PROCESSING NUMERICAL CONTROL PROGRAM

Abstract: A system comprises a CPU (10), a ROM (11), a RAM (12), a tape reader (13), a CRT (15), a key borad (16), a ROM writer (17), a ROM cassette (18), a compiler cassette (19), a bus (25) and a machine tool a servomotor (20), a tachogenerator (21), a speed control unit (22), a position detector (23) and a position controller (24). In editing mode, an NC program is a high-level language on a paper tape (14) is converted into a machine language by a compiler cassette (19) and stored in teh ROM cassette (18) by the ROM writer (17). In executing mode, the ROM cassette (18) is connected to the bush (25) and the NC program is transferred to the RAM (12) so that the NC program can be executed.

Description: The present invention relates to processing a numerical control program for controlling a numerical control system. Recent numerical control systems which mostly incorporate computers are called computerized numerical control (CNC) systems. The CNC system has a microprocessor and other components such as a tape reader, switches, lamps, and a servomechanism, which are connected to the microprocessor through a bus line extending therefrom. The states of all of these components are detected from time to time by the microprocessor, which applies commands to these components to effect various operations according to a numerical control program. The numerical control program is ordinarily stored on a punched tape. Before the CNC system is operated, the punched tape is fed through the tape reader which then transfers the program from the punched tape into a random-access memory (RAM) in the CNC system. In some CNC systems, a numerical control program stored in a read-only memory (ROM) in the CNC system is transferred into the RAM. Thereafter, numerically controlled operation is effected according to the numerical control program stored in the RAM. A typical prior art CNC, which provides the basis for the preamble of the attached claim 1, is disclosed in EP-A-0 002 750. The numerical control program in the punched tape or the RAM is stored in the form of a numerical control high-level language such as FAPT. Each time the numerical control program is executed, it is usually converted to a machine language applicable to the numerical control system by using a compiler stored in the numerical control system. According to the prior art, when the numerical control program is executed, a tape editing area in the numerical control program must be used, and the processing time includes a time required to compile the numerical control program. Thus, the numerical control program cannot quickly be executed. Where a paper tape is employed to store a numerical control program, difficulty is experienced in keeping secrets since the numerical control program can easily be read by a human being. Therefore, it is an object of the present invention to provide an apparatus for processing a numerical control program, which will eliminate or reduce the aforesaid problems, and more particularly to an apparatus for processing a numerical control program, wherein secrecy is provided by storing a numerical control program in a ROM, the program is thus protected against destruction, and the numerical control program can quickly be processed. According to the present invention there is provided a numerical control system comprising: input means for reading into the system a numerical control program, for controlling the system, which is in the form of a high-level-language; a compiler memory storing therein a compiler for converting said numerical control program in the form of a high-level language to a machine language; converting means for converting, with the compiler, said numerical control program input to the numerical control system in the form of a high-level language to a machine language applicable to the numerical control system; a ROM; ROM writing means for writing into the ROM the numerical control program after its conversion to the machine language; and control means for controlling the numerical control system according to the numerical control program stored in the ROM, characterised in that the ROM and the compiler memory are each detachable from the remainder of the numerical control system and the ROM can be disconnected from the ROM writing means after the numerical control program has been stored therein, and can subsequently be reconnected to the numerical control system in such manner that the numerical control program stored in the ROM can be read into the numerical control system for execution thereby. An embodiment of the present invention will hereinafter be described in specific detail with reference to the drawing. The figure is a block diagram of an embodiment of the present invention, showing a numerical control system (CNC) in the form of a computer connected to peripheral devices. Denoted in the figure at 10 is a central processing unit (CPU), 11 a read-only memory (ROM) storing an operating system and invariable data, 12 a random-access memory (RAM) for temporarily storing data when numerical control operation is effected and for storing a numerical control (NC) program which is input from an external source, and 13 a tape reader for reading a stored NC program from a paper tape 14. The NC program stored in the paper tape 14 is stored in the form of a high-level language for the NC program, such as FAPT. Designated at 15 is a CRT display unit for displaying machining data while NC machining is being effected and the NC program being edited, 16 a keyboard, and 17 a ROM writer associated with the numerical control system for writing the NC program as converted to a machine program (described later) into a ROM cassette 18. The ROM cassette 18 is a cassette comprising a bubble memory or an EPROM and detachable from the numerical control system. When attached to the numerical control system, the ROM cassette 18 is connected to a bus line and controlled by the CPU 10. Denoted at 19 is a compiler cassette having a ROM storing a compiler for converting the NC program expressed by a high-level language such as FAPT to a machine program. Like the ROM cassette 18, the compiler cassette 19 is a cassette comprising a bubble memory or an EPROM and detachable from the numerical control system. When attached to the numerical control system, the compiler cassette 19 is connected to the bus line and controlled by the CPU 10. Designated by the reference numeral 20 is a servomotor of a machine tool or a robot which is controlled by the NC System. A rotational speed signal of the servomotor 20 is fed from a tachometer generator 21 back to a speed control unit 22, and an angular position signal of the servomotor 20 is fed from a position detector 23 back to a position control unit 24. Denoted at 25 is a bus. While there are various other devices connected to the bus of the numerical control (CNC) system, they will not be described for brevity. Operation of the embodiment of the present invention will be described below. The contents of an NC program expressed by a high-level language such as FAPT and stored in a storage medium such as the paper tape 14 are first converted to a format which can easily be executed by the numerical control (CNC) system, by using a compiler stored in the compiler cassette 19 attached to the numerical control (CNC) System. The conversion to such a format is, for example, the conversion from the contents of the NC program to a machine language. The contents of the NC program as converted to the format which can easily be executed by the numerical control (CNC) system are temporarily stored in the RAM 12, and then read out and written into the ROM in the ROM cassette 18 by the ROM writer 17. As many ROM cassettes 18 as desired can be copied by such a process. The above editing process is executed while putting the numerical control (CNC) system in an editing mode. For the numerical control (CNC) system to execute a numerical control process, the ROM cassette 18 which stores the numerical control program as converted by the ROM writer 17 to the format that can easily be executed by the numerical control (CNC) system is connected to the numerical control (CNC) system, as indicated by the dotted lines, and the stored NC program is read out and stored into the RAM 12. Thereafter, the NC process is executed according to the NC program stored in the RAM 12. With the present invention, as described above, the numerical control program is converted to the format which can easily be executed for numerical control, by using the memory device storing the compiler, and the converted program is stored into the ROM cassette by the ROM cassette writer. Subsequently, the numerical control program is executed by employing the ROM cassette. Accordingly, program secrecy is provided, and the numerical control program can quickly be executed. Industrial Applicability The present invention is applicable to not only numerically controlled machine tools, but also all devices controlled by numerical control systems, such as a device for controlling an industrial robot, a device for controlling an electric discharge machine tool, and the like. The compiler cassette and the ROM cassette can be replaced with floppy discs, portable magnetic discs, magnetic tape cassettes, or the like through a mere design change.

Claims: A numerical control system comprising: input means (13) for reading into the system a numerical control program, for controlling the system, which is in the form of a high-level language; a compiler memory (19) storing therein a compiler for converting said numerical control program in the form of a high-level language to a machine language; converting means for converting, with the compiler, said numerical control program input to the numerical control system in the form of a high-level language to a machine language applicable to the numerical control system; a ROM (18); ROM writing means (17) for writing into the ROM (18) the numerical control program after its conversion to the machine language; and control means (10) for controlling the numerical control system according to the numerical control program stored in the ROM (18), characterised in that the ROM (18) and the compiler memory (19) are each detachable from the remainder of the numerical control system and the ROM (18) can be disconnected from the ROM writing means (17) after the numerical control program has been stored therein, and can subsequently be reconnected to the numerical control system in such manner that the numerical control program stored in the ROM (18) can be read into the numerical control system for execution thereby. A numerical control system according to claim 1, wherein the compiler memory (19) is a compiler cassette. A numerical control system according to claim 2, wherein the compiler memory (19) comprises a bubble memory. A numerical control system according to claim 2, wherin the compiler memory (19) comprises an EPROM. A numerical control system according to any preceding claim, wherein the ROM (18) is a ROM cassette. A numerical control system according to claim 5, wherein the ROM (18) comprises a bubble memory. A numerical control system according to claim 5, wherein the ROM (18) comprises an EPROM.

Inventors: IWAGAYA, TAKASHI
Applicants: FANUC LTD.
Application year: 1987
Main classification: G05B19
IPC codes: G05B19