JPS6353607A - Computer numerical controller - Google Patents

Abstract

PURPOSE:To simplify a circuit constitution and to facilitate the function distribution of respective computers by coupling plural computers with a high speed serial transmitting circuit instead of a sharing memory. CONSTITUTION:A computer numerical controller CNC controls a machine tool in accordance with a processing program, and a master computer 1 executes a main control to numerically control the processing program. Slave computers 2 and 3 execute the slaved control to drive motors 5 and 6 with the data received from a master control. Respective computers delivers the data through high speed serial transmitting lines 9 and 10. Since the CNC device executes the control by a time division, the master control transmits serially the data in which a motor is rotated by the slaved control for respective sampling times. The slaved control drives the motor connected for respective sampling times and simultaneously, the present position of the machine tool is transmitted through line drivers 7 and 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a computerized numerical control device (hereinafter referred to as a CNC device) for controlling machine tools, robots, etc.

(Prior Art) Conventional numerical control devices were pure hardware control devices, but with the rapid development of microcomputers, they have changed to computerized CNC devices.

It is possible to control a CNC device with a single computer if the slow operation of the machine tool being driven is acceptable, but in reality it is not practical to process with a single computer, so multiple CNC devices can be used. Functions are distributed using computers, and some of them are realized using hardware.

FIG. 2 shows an example of a CNC device using multiple computers, in which the multiple computers 1, 2.3 use a shared memory 4 for receiving and passing data, and the computers 2 and 3 drive the motors 5, 3, and 4. 6 is controlled.

A CNC device using a shared memory has the advantage of improved processing speed and richer functions than a CNC device using a single computer.

In addition, as shown in FIG. 3, the motor drive computer 2,
It is also possible to control the motors 5 and 6 by using the main computer 1 as an input/output device.

However, with the conventional shared memory method described above, multiple computers may compete for the shared memory at the same time, so bus signals around the shared memory are subject to operational timing constraints, resulting in an increase in the number of machine tool axes (number of motors). In some cases, the circuit configuration becomes complicated.

Furthermore, the input/output device method has a problem in that the number of input/output signal lines increases as the amount of data input/output by the computers 2, 3 increases.

(Problems to be Solved by the Invention) It is an object of the present invention to provide a computerized numerical control device that facilitates data transfer between a plurality of computers and can accommodate expansion of functions such as an increase in the number of control axes. The purpose is

[Structure of the invention]

(Means and effects for solving the problem) The present invention connects multiple computers using a high-speed serial transmission circuit instead of a shared memory, thereby simplifying the circuit and increasing control functions by adding more computers. This is a CNC device that allows for easy expansion.

(Example) An embodiment of a numerical control device according to the present invention is shown in FIG.

Figure 1 shows multiple computers 1゜2.3, similar to Figure 2.
However, the computers are connected by high-speed serial transmission lines 9 and 10.

Line driver buffers 8 are connected to the transmission lines of computers 2 and 3, respectively, and
connect motors 5 and 6 as input/output devices, respectively.

The CNC device controls the machine tool according to the machine tool program, and the computer 1 executes main control that numerically processes the machine tool program. Computers 2 and 3 execute slave control to drive motors 5 and 6, respectively, based on data received from the main control. Each computer receives and passes data via high-speed serial transmission lines 9 and 10.

Since the CNC device performs time-division control, the main control serially transmits data for the rotation of the motor 3 in the slave control at each sampling time. Further, the slave control drives the connected motor at each sampling time, and at the same time sends data such as the current position of the machine tool via the line trinos 7 and 8.

Further, when the machine tool exceeds a movable position, the slave control prohibits motor drive and sends the status to the main control.

In addition, computer 2 and 3 line try no bear, 8
can be easily realized with a three-stay +- circuit integrated circuit that is normally in a high impedance state.

Furthermore, in the above embodiment, one motor is connected to the computer 2-3 for slave control, but it is possible to connect multiple motors according to the computer's capabilities, and the computer for slave control can basically Since it has a party line configuration, it can be easily expanded.

〔Effect of the invention〕

As explained above, according to the present invention, multiple computers are connected through high-speed serial transmission, which simplifies the circuit configuration, and also makes it easy to distribute functions among the computers, making it easy to add functions to the CNC device. It is.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an embodiment of the present invention, FIG. 2 is a system diagram of a conventional shared memory type CNC device, and FIG. 3 is a system diagram of a conventional input/output device type CNC device. 1... Main computer 2, 3... Slave computer 4... Shared memory 5, 6... Motor 7.
8...Line driver 9,10...Transmission line agent Patent attorney Nori Chika Ken Yudo Hirofumi Mitsumata 2 Diagram 3

Claims (1)

[Claims] A common main computer that preprocesses the operation program for each drive shaft, multiple slave computers that drive and control each drive shaft according to commands from the main computer, and data is serially transmitted between the main computer and slave computers. A computerized numerical control device characterized by having a transmission line for high-speed transmission.