JP2690683B2 - Numerical control unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerical control device for controlling a machine tool, a robot or the like, and more particularly to a numerical control device in which a control unit and a servo unit are separated.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing an example of a conventional numerical control apparatus.

Referring to FIG. 4, a conventional numerical control device includes a control unit 7 which outputs a control signal 22 for each command such as a position command based on various numerical control programs, and a control signal from the control unit 7. N servo units 81, 82 for driving n control axes based on 22.
..., 8n, the control unit 7 and each servo unit 81,
., 8n, and a data bus 21 for communicating with digital data. Here, n is a positive integer and represents the number of control axes required for a machine tool, a robot, or the like.

The control unit 7 includes a bus buffer 13 for driving the data bus 21, a control circuit section 71 for controlling all programs in the control unit 7, and a control circuit section 7.
And a program storage section 72 for storing a control program executed by the.

Further, each servo unit 81, 82, ...
8n includes bus buffers 41, 42, ..., 4n for driving the data bus 21, and number setting switches 51, 52 ,.

Reference numeral 23 is a terminal device for impedance matching of the data bus 21.

Next, the operation of this numerical controller will be described.

In this conventional numerical controller, the control unit 7 and a plurality of servo units 81, 82, ..., 8n are provided.
, And 8n are connected to each other via one data bus 21, it is necessary to set individual numbers for identifying the servo units to the servo units 81, 82, ..., 8n. It is the number setting switch 5 that artificially sets this individual number.
, 52, ..., 5n, and the individual numbers must be set so that they do not overlap in all n servo units.

When the control unit 7 transfers data to an arbitrary servo unit, the individual numbers set in the servo units 81, 82, ..., 8n are stored in the control unit 7 as variables in advance.

Based on this variable, the control circuit section 71 of the control unit 7 first sends the address of the target servo unit to the data bus 21, and then sends the data to be transferred to this servo unit.

The servo units 81, 82, ..., 8n constantly monitor the data bus 21, and only the servo unit matching this address fetches the data sent out following the address from the data bus 21.

On the contrary, the control unit 7 is replaced by the servo unit 8
, 8n, the control circuit section 71 of the control unit 7 first sends out the addresses of the servo units 81, 82, ..., 8n to the data bus 21. The servo unit matching this address sends the data to be transferred to the control unit 7 to the data bus 21, so that the control unit 7 can fetch the necessary data from the data bus 21.

In this way, the control unit 7 exchanges necessary digital data with the servo units 81, 82, ..., 8n, and the servo units 81, 82,
..., 8n controls the positions of machine tools and robots.

[0014]

In this conventional numerical control device, when the individual numbers of a plurality of servo units are set redundantly due to an individual number setting error in each servo unit, the control unit takes in digital data. In this case, there is a problem in that multiple bus buffers with overlapping individual numbers output digital data to the data bus at the same time and the digital data collide on the data bus, which may damage the bus buffer. .

The object of the present invention is to avoid the damage of the bus buffer by detecting the individual number of the servo unit through the data bus, and to notify the operator of the duplicated individual number if they are duplicated. Is to provide a numerical control device capable of promptly correcting the duplication by knowing which control axes of the machine tool, the robot and the like overlap.

[0016]

According to the present invention, a control unit for outputting each command including a position command based on various numerical control programs, and n control units based on each command from the control unit. In a numerical controller having n servo units for driving an axis and a data bus for communicating digital data between the control unit and each servo unit, each servo unit is provided with The servo unit number control circuit section for controlling the transmission of the individual number set in the own servo unit in response to the individual number transmission request signal is provided, and the control unit duplicates the individual number received from the servo unit through the data bus. A numerical controller characterized by comprising individual number detecting means for detecting the presence or absence of setting is obtained.

When the control unit transmits the individual number transmission request signal to each of the servo units through the servo control bus and the individual number detecting means detects that the individual number from each of the servo units is duplicated. There is provided a numerical control device including a control circuit unit for notifying the outside to that effect, and a program storage unit for storing a control program executed by the control circuit unit.

[0018]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a numerical controller according to the present invention, FIG. 2 is a sequence chart of transmission / reception of individual number transmission request signal and individual number in FIG. 1, and FIG. 3 is a control circuit section in FIG. It is a flow chart for explaining an individual number detection operation.

Referring to FIG. 1, the numerical controller of this embodiment is different from the conventional numerical controller (shown in FIG. 4) in that each servo unit has a servo unit number control circuit section. , And the contents of the program processing of the control circuit unit in the control unit (that is, the control program stored in the program storage unit) are different.

That is, the numerical control device of the present embodiment includes a control unit 1 for outputting a control signal 22 for each command such as a position command to the servo control bus 20 based on various numerical control programs, and the control unit 1 N servo units 31, which drive n control axes based on each command of
, 3n, and a data bus 21 for communicating digital data between the control unit 1 and each servo unit 31, 32, ..., 3n.

The control unit 1 includes a bus buffer 13 that drives a data bus 21, a control circuit section 11 that controls all programs in the control unit 1, and a control circuit section 1.
And a program storage unit 12 for storing an individual number detection program of each servo unit executed by.

Further, each servo unit 31, 32, ...
3n are bus buffers 41, 42, ..., 4n for driving the data bus 21, respectively, and number setting switches 51, 52, ..., 5n for setting individual numbers of the own servo unit.
And a servo unit number control circuit for controlling, when receiving an individual number transmission request signal from the control unit 1 through the servo control bus 20, transmitting the individual number set in the own unit to the control unit 1 through the data bus 21 in response to the signal. , 6n.

The individual number transmission request signal 101 output from the control circuit section 11 of the control unit 1 is the servo control bus 2
It is input to the servo unit 31 through 0. Further, the individual number transmission request signal 10 output from the control circuit unit 11
2 passes through the servo unit number control circuit section 61 of the servo unit 31 and is input to the servo unit 32. Similarly, the individual number transmission request signal is input to each servo unit, the individual number transmission request signal 10n is input to the servo unit 3n, and the individual number transmission is output through the servo unit number control circuit section 6n of the servo unit 3n. The request signal is open.

Here, each servo unit 31, 32,
..., 3n have individual numbers "1", "2", ..., respectively.
It is assumed that “n” is set.

Next, the operation of this embodiment will be described with reference to FIG.

In the control unit 1, the control circuit section 11 executes the individual number detection program of each servo unit stored in the program storage section 12 and sends the individual number sending request signal 101.

When the individual number transmission request signal 101 is input, the servo unit number control circuit section 61 of the servo unit 31 outputs its own individual number "1" to the data bus 21 and then sequentially receives it from the control circuit section 11. The individual number transmission request signals 102, 103, ..., 10n are output to the servo unit 32.

When the individual number transmission request signal 102 is input, the servo unit number control circuit section 62 of the servo unit 32 outputs its own individual number "2" to the data bus 21 and then sequentially receives it from the control circuit section 11. .., 10n are output to the downstream servo unit.

Similarly, the individual number transmission request signal is input to each servo unit and each individual number is output to the data bus 21, and the servo unit number control circuit section 6n of the servo unit 3n outputs the individual number transmission request signal. 10
When n is input, it outputs its own individual number “n” to the data bus 21.

The control circuit section 11 of the control unit 1 receives the above-mentioned individual numbers sequentially output from the servo units 31, 32, ..., 3n from the data bus 21 and stores and stores them inside.

Next, the individual number detecting operation in this embodiment will be described with reference to FIG.

In the control unit 1, the control circuit section 11 reads out and executes the individual number detection program of each servo unit stored in the program storage section 12.

That is, after the power supply of the numerical control device is turned on (step S1), the control circuit section 11 makes a servo unit individual number transmission request (S2), and each servo unit 31, 32, ..., 3n is addressed. The individual number transmission request signals 101, 102, 103, ..., 10n are output to.

After making the servo unit individual number transmission request, the control circuit unit 11 waits for a predetermined time and monitors the reception of the individual number from each servo unit (S3). Therefore, in this standby time, the individual numbers "1", ..., "n" are assigned to the data bus 21 from all the servo units from the servo unit 31 to the servo unit 3n.
And is stored in the control circuit unit 11 (S4).

After that, the control circuit unit 11 inspects the individual numbers "1", ..., "N" of all the stored / memorized servo units to check whether or not the numbers are duplicated (S5). If there is no number duplication (No in S5), the process ends.
If there is a number duplication (Yes in S5), the operator is notified and error processing is performed (S6).

In the present embodiment, an example in which the individual number detecting process is performed by the detecting means by software is shown, but this can be easily performed by a logic circuit (hardware).

[0038]

As described above, according to the present invention, a control unit that outputs each command including a position command based on various numerical control programs, and n control axes based on each command from this control unit. In a numerical controller provided with n servo units to be driven and a data bus for communicating digital data between the control unit and each servo unit, each servo unit receives an individual number transmission request signal from the control unit. An individual number detecting means for detecting whether or not there is a duplicated setting of the individual number from the servo unit received through the data bus. With the provision of the control unit, after turning on the power supply of the numerical controller, the control unit It examines the set individual number Te, it is possible to immediately error processing if individually numbered overlap setting, it is possible to avoid damage to the data bus.

Therefore, there is an advantage that there is no room for human error leading to damage of parts and the reliability of the numerical controller is remarkably improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of a numerical controller according to the present invention.

FIG. 2 is a sequence chart of transmission / reception of an individual number transmission request signal and an individual number in FIG.

FIG. 3 is a flowchart for explaining an individual number detecting operation of the control circuit unit in FIG.

FIG. 4 is a block diagram showing an example of a conventional numerical control device.

[Explanation of symbols]

1, 7 Control unit 11, 71 Control circuit unit 12, 72 Program storage unit 13, 41, 42, ..., 4n Bus buffer 20 Servo control bus 21 Data bus 22 Control signal 23 End portion 31, 32, ..., 3n, 81 , 82, ..., 8n Servo unit 51, 52, ..., 5n Number setting switch 61.62. …, 6n Servo unit number control circuit section 101, 102, 103, ..., 10n Individual number transmission request signal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Toru Nakano 5-7-1 Shiba 5-chome, Minato-ku, Tokyo Inside NEC Corporation (56) Reference JP-A-3-225506 (JP, A) JP-A-5 -16057 (JP, A)

Claims (2)

(57) [Claims] 1. A control unit that outputs each command including a position command based on various numerical control programs, and n servo units that drive n control axes based on each command from the control unit. A numerical control device comprising a data bus for communicating digital data between the control unit and each servo unit,
Each of the servo units includes a servo unit number control circuit unit that controls the transmission of the individual number set in the own servo unit in response to an individual number transmission request signal from the control unit, and the control unit receives through the data bus. A numerical controller comprising an individual number detecting means for detecting the presence / absence of duplicate setting of the individual number from the servo unit. 2. The control unit sends the individual number sending request signal to each of the servo units through a servo control bus, and when the individual number detecting means detects that the individual number from each of the servo units is duplicated. The numerical control device according to claim 1, further comprising a control circuit unit for notifying the outside to that effect, and a program storage unit for storing a control program executed by the control circuit unit.