JPH01177106A - Transmission system for control program - Google Patents

Abstract

PURPOSE:To omit a waiting state for a control program of a control program requiring the continuous control and to maintain the normal numerical control by securing such a constitution where the control program is always divided at the dividable areas regardless of the program capacity and then sent successively to a numerical controller. CONSTITUTION:When a control program 11 is sent to a numerical controller 5 via an interface device 4, the program 11 is divided at an area including such an instruction that has no hindrance for execution of the following instructions even though the numerical control is temporarily discontinued. Furthermore the program 11 is divided in such a size that can effectively use a buffer 9 of the device 4. Thus a transmission waiting state can be set in a control process where no problem occurs despite the temporary discontinuation of the control and even in case the controller 5 is set under a waiting state for transmission of the program 11. In addition, a transmission frequency equivalent to the conventional one is secured for the program 11.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a control program transmission method that connects a host computer and a numerical control device using a communication line LAN 'ji to transmit a control program. .

[Conventional technology]

In recent years, when controlling a large number of machine tools using numerical control devices, instead of inputting the entire control program using paper tape, it is now possible to create a control program in advance on a host computer and configure it using communication lines and communication devices. L to be
A system for transmitting data to a numerical control device using ANt has been implemented. When constructing such a system, an interface device is required that connects a conventional numerical control device and a communication device and mediates data transmission.

This interface device is a device that receives control programs transmitted from a host computer and transmits them all sequentially to a numerical control device. Generally, communication between a host computer and an interface device;
Communication between the interface device and the numerical control device is not synchronized and the transmission speeds are different, so the interface device has a A "buffer" is required to store the data. However, since this buffer capacity is finite, in order to transmit a control program so large that it exceeds the buffer capacity, it is necessary to divide it into multiple parts and send it. Therefore, when transmitting the control program to the numerical control device, the host computer and the interface device perform the following operations. The host computer first retrieves the programs sequentially from its own auxiliary storage device and transmits them, and then temporarily suspends transmission when the interface device's reception buffer is filled. After receiving the control program from the host computer, the interface device transmits the control program in sequence until the control program storage area of the numerical control device is full, as described above. Then, the remaining control program in the buffer is transmitted every time there is a request from the numerical control device.

However, in data transmission between a host computer and an interface device via the above-mentioned communication line and communication device, the response time from when one device issues a data transmission request to the other until it actually receives the data is The time is long. Therefore, the time required for the interface device to transmit the control program, from sending it to the SJf host computer to actually receiving the control program, cannot be ignored in many cases on the numerical side '6i' [-]. Therefore, if the control program storage area of the numerical control device becomes empty and there is no control program to be transferred to the buffer area of the interface device, the interface device will receive and receive the next control program. During this period, the numerical control device has no commands to execute and is in a state where it waits for the next command to be input.

This state is highly likely to have a serious adverse effect on a control process that needs to be performed continuously without stopping, and normal numerical control cannot be expected.

[Problem that the invention seeks to solve]

In the above-mentioned LAN system, first of all, due to the limited buffer capacity of the interface device, it became necessary to divide the control program into a plurality of parts and sequentially transmit them to the numerical control device. At this time, the control program is divided at the point where the buffer becomes full at the time of transmission, regardless of the types of instructions contained therein. Furthermore, since the data is transmitted via a communication device, the response time is long, and there is a period during which the numerical control device waits for instructions until the transmission of the divided control program begins. As a result, if a program is divided at a point corresponding to a control process that requires control to be performed continuously without stopping, a problem arises in that control becomes temporarily discontinuous due to waiting for transmission. Ta. This can lead to fatal control errors depending on the controlled object. [Means for solving the problem] In order to solve the above problem, the present invention aims to solve the above problem by When transmitting the control program to the control device, the control program is divided at locations where there are instructions that will not interfere with the execution of the next instruction even if the control is temporarily interrupted during numerical control. The control program is divided into parts that can be used effectively.

[Effect]

When the above method is used, regardless of the capacity of the control program, it is always divided at possible division points and sequentially transmitted to the numerical control device. As a result, there is no need to wait for the transmission of a control program during a control process that requires continuous tJ control as in the prior art, and normal numerical control can be maintained.

〔Example〕

Hereinafter, the present invention will be specifically described based on embodiments shown in the drawings. Figure 1 shows an overview of the system.

In the figure, 1 is a host computer which manages the entire system. This K stores the control program,
An auxiliary storage device la is added for storage. 2 is a communication line, and a coaxial cable or the like is used. 3 (3-1, 3-2) are communication devices that provide communication services using the communication line 2. An interface device 4 mediates data transmission between the communication device 3 and a numerical control device to be described later. 5 and 6 are a numerical control device and a machine tool controlled by the numerical control device, respectively.

7 is a workpiece processed by a machine tool.

In the embodiment configured in this way, when downloading the control program from the host computer 1,
That is, a case will be considered in which a control program is transmitted to the numerical control device 5 via the interface device 4. First, the flow of data in the system shown in FIG. 1 is briefly shown in FIG. 2. The host computer 1 transmits a part of the control program 11 from the auxiliary storage device 7-a via the main storage device 8 to the buffer 9 of the interface device 4 ((2) and (2) in FIG. 2). Interface device 4
transfers this program to the program storage area 1o of the numerical control device 5 (■ in the figure).

The numerical control device 5 sequentially executes control programs to control the machine tool 6 and process the workpiece 7. However, when the control program storage area 1o is empty or has a certain amount of space, a program transmission request (■ ) to the interface device 4. If the interface device requires program transmission from the host computer,
Outputs a transmission request (■ in the same figure) to the host computer.

The host computer side receives this and transmits the control program.

Now, in the host computer 1, the auxiliary storage device 1-a
Before dividing the control program stored in
A division table (an example is shown in FIG. 4) to be referred to at the time of division is created according to the flowchart shown in FIG. This table lists in order the parts that can be divided and the control program capacity of each small block when each small block is divided into multiple parts based on this information. Based on this table, the number of blocks that can be transmitted at one time can be determined. The partitioned table is created on the main storage device 8 by the host computer executing the following procedure.

Here, an example of a division determination point and a program will be explained with reference to Table 1 below.

One way to determine whether it is divisible is to detect a tool exchange command in a control program for a machine tool. At the time of tool change, the cutting tool is completely separated from the workpiece, so even if a control waiting state occurs due to program transfer, there is little chance of it having a negative impact on the shape and dimensions of the workpiece. . The actual procedure and command code for tool exchange may vary depending on the manufacturer and type of numerical control device, but by searching for a specific code, it is possible to clearly detect the location where tool exchange is to be performed. For example, in FANUC's CNC equipment, the numerical value following the code "M" can be used to perform on/off control such as starting and stopping the spindle of a machine tool, or changing tools. Therefore, the tool change is M6
”, a partitioned table can be created by searching sequentially from the beginning of the control program for locations with the code “M6”.

Next, the operation of the above embodiment will be explained with full reference to the flowchart in FIG.

■ The control program basically consists of multiple lines, and each line has a structure of @11 line instructions. This procedure sets the line counter to 0.

■ Set the capacity counter that counts the number of characters (number of bytes) in each line of the control program to O.

(2) Take one line of the control program from the beginning of the control program from the auxiliary storage device 1-a and store it in the main storage device R8.

■ Increment the contents of the line number counter by 1, then accumulate the number of characters in this line in the capacity counter.

■ Determine whether the line retrieved in ■ is the last line of the control program, and if it is the last line, execute ■, otherwise execute ■.

■ By analyzing the command in the line extracted in step (■), it is possible to determine that even if control is temporarily interrupted due to waiting for transmission of the control program after the numerical control device executes this line, it will not affect the subsequent control process. Determine whether or not there is. If it can be interrupted, execute ■; otherwise, execute ■.

■ Store the current row count and capacity counter contents in the partitioned table.

■ After performing the same processing as above, end all processing.

After completing the partitioned table, the host computer 1 sequentially transmits the control program in the following manner every time it receives a control program transmission request (2) from the interface device 4. The control program is retrieved from the auxiliary storage device 7-a again, and by referring to the division table, it is divided into parts within the maximum range that does not exceed the buffer capacity of the interface device 4, that is, one or more parts in the division table. Control programs are transmitted in units of multiple blocks.

In response to this, the interface device 4 transmits the program to the numerical control device according to the flowchart shown in FIG. In this case, similarly to the above, the unit of one transmission is performed in units of subdivided blocks in the division table.

The entire procedure shown in Figure 5 will be explained below.

■ Receive several blocks of the control program transmitted from the host computer 1 and store it in a buffer.

(2) Transmit the programs in the buffer until the control program storage area of the numerical control device 5 is as full as possible. In this case as well, data is transmitted in units of blocks in the partitioned table.

(1) Determine whether the block in which transmission has been completed is the last block of the control program, and if it is the last block, terminate, otherwise execute (2).

(2) Determine whether or not there is a control program transmission request (2) from the numerical control device 5. If there is a request, execute (2); if not, wait until this is detected.

■ Determine whether there is a control program to be transmitted to the numerical control device in the buffer, and if so, return to ■; if not, return to ■
Execute.

■ Outputs the next control program transmission request ■ to the host computer 1.

As described above, in this embodiment, the control program is divided and transmitted based on the division table created before the control program is transmitted.

Furthermore, the unit of one transmission is the block unit in the partition table, both from the host computer to the interface device and from the interface device to the numerical control device. In this example, the host computer created the partition table and performed the partitioning during transmission, but it is also possible to perform this together with the interface device or by the interface device alone. Furthermore, although a previously prepared table was used for information for division, a method of detecting information for division while transmitting a control program is also conceivable.

〔Effect of the invention〕

As described above, according to the present invention, the control 7 to be transmitted
°Using the information on the splittable locations in the program, the control program can be divided at all appropriate locations during transmission, and each transmission unit is entirely divided by the program in the division table.
This can be done in units of Tsuku. Therefore, even if the numerical control device waits for control program transmission, it waits for transmission within a control process that does not affect subsequent numerical control, that is, a control process that does not cause problems even if control is temporarily interrupted. state. Furthermore, since the buffer of the interface device is always utilized to the maximum extent, the control program can be transmitted with the same number of transmissions as in the conventional transmission method.

[Brief explanation of the drawing]

Figure 1 is a system configuration diagram showing an example of a non-explosion.
The figure shows the flow of data in the same embodiment, Figure 3 is a flowchart showing the operation of creating a partitioned table in the same embodiment, Figure 4 is an explanatory diagram of the partitioned table in the same embodiment, and Figure 5 shows the same implementation. 3 is a flowchart showing a transmission procedure of an example interface device. DESCRIPTION OF SYMBOLS 1... Host computer, 1-a... Auxiliary storage device, 2... Communication device, 3... Communication line, 4...
Interface device, 5... Numerical control device, 6...
・Machine tool, 7... Workpiece, 8... Main memory device, 9
... Buffer, 10... Control program storage area, 11... Control program. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure fJ4

Claims (1)

[Claims] In a system consisting of a host computer, a numerical control device, and an interface device that connects the two via a communication line, when a control program is transmitted from the host computer to the numerical control device, the host computer either The control program is divided into multiple blocks at locations where the machining accuracy will not be adversely affected even if the control operation of the machine is interrupted over time, by the interface device or joint analysis by the two. A control program transmission method characterized by sequential transmission of each block.