JPH0822313A - Numerical controller - Google Patents

Abstract

PURPOSE:To easily set data for origin returns of respective axes by the numerical controller which makes the origin returns of the master and slave axes on a grid basis. CONSTITUTION:An axis movement command means 1 commands the master axis 3 and slave axis 4 to move and when the grids of the master axis 3 and slave axis 4 both start, an axis stop control means 2 controls the stop of the movement of the master axis 3 and slave axis 4. A position shift quantity calculating means 5 calculates the quantities of position shifts of the grid positions of the respective axes when the master axis 3 and slave axis 4 stop from moving, and the calculated position shift quantities are stored in a position shift quantity storing means 6. An origin return control means 8, on the other hand, places the master axis 3 in origin return operation on the basis of a previously set grid shift quantity 7, and then places the master axis 3 and slave axis 4 in origin return operation on the basis of the value obtained by adding the grid shift quantity 7 and position shift quantity as to the slave axis 4.

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 returning to the origin by a grid method, and more particularly to a numerical control device for synchronizing a master axis and a slave axis.

[0002]

2. Description of the Related Art In order to accurately machine a work according to a machining program of a numerical controller, the origin on the machine coordinates must be accurately grasped by the numerical controller. Therefore, the numerical controller sets the origin by returning the movable part of the machine to the origin.

As a method for returning to the origin, there is a method in which a limit switch for deceleration is provided in the vicinity of the origin of the movable part of the machine. This is the amount of grid shift that is the difference between the origin and the grid position from the time when the driver first decelerates the servo motor when the dog is stepped on after the home position return command is issued The axis movement is stopped by shifting only. This makes it possible to accurately stop the axis at the origin. The grid shift amount is a value measured in advance by manual operation or the like.

By the way, in a numerical controller for controlling a machine tool having a master axis and a slave axis, it is necessary to make the origins of these axes coincide. However, since the grid positions on the master axis and slave axis do not match, conventionally, the grid shift amount is measured for each axis, the shift amount between the two is calculated, and the parameters are set, and the shift is set. The origin was returned based on the amount.

[0005]

However, as described above, since the measurement of each grid shift amount is performed manually, it takes a lot of time to find the shift amount.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a numerical control device capable of simplifying the work of setting the data for the origin return of the master axis and the slave axis. To do.

[0007]

According to the present invention, in order to solve the above-mentioned problems, in a numerical control device for returning the origin of a master axis and a slave axis by a grid method, a command is issued for each axis movement of the master axis and the slave axis. Axis movement command means, and axis stop control means for controlling the movement of the master axis and the slave axis to stop when the grids of the master axis and the slave axis both rise, and the master axis and the slave axis have stopped moving. At this time, a positional deviation amount calculating means for calculating the positional deviation amount of the grid position of each axis, a positional deviation amount storage means for storing the calculated positional deviation amount, and a preset grid shift amount for the master axis. The origin return operation is performed based on the above, and for the slave axis, the grid shift amount and the positional deviation amount are added. Numerical control device, wherein there is provided to have a, and the origin return control means for performing the homing operation based on.

[0008]

The axis movement command means commands the movement of each axis of the master axis and the slave axis, and when the grids of the master axis and the slave axis both rise, the axis stop control means moves the master axis and the slave axis. Stop control. The positional deviation amount calculating means calculates the positional deviation amount of the grid position of each axis when the master axis and the slave axis stop moving,
The calculated positional deviation amount is stored in the positional deviation amount storage means.

On the other hand, the origin return control means performs the origin return operation for the master axis based on the preset grid shift amount, and for the slave axis based on the value obtained by adding the grid shift amount and the positional deviation amount. Perform home return operation.

[0010]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the concept of the function of the present invention. The axis movement command means 1 commands each axis movement of the master axis 3 and the slave axis 4, and when each grid of the master axis 3 and the slave axis 4 rises, the axis stop control means 2 causes the axis stop control means 2 to move to the master axis 3 and the slave axis. The movement of the shaft 4 is stopped and controlled.
The positional deviation amount calculation means 5 calculates the positional deviation amount of the grid position of each axis when the master axis 3 and the slave axis 4 stop moving, and the calculated positional deviation amount is stored in the positional deviation amount storage means 6. To do.

On the other hand, the origin return control means 8 controls the master shaft 3
Is performed on the basis of a preset grid shift amount 7, and for slave axis 4, based on a value obtained by adding the grid shift amount 7 and the positional deviation amount,
Performs a return-to-origin operation for master axis 3 and slave axis 4.

FIG. 2 is a block diagram showing a schematic configuration of hardware of the numerical controller according to the present invention. The numerical controller is mainly composed of the processor 11. Processor 1
Reference numeral 1 controls the entire numerical controller according to a system program stored in the ROM 12. This ROM12 has E
PROM or EEPROM is used. ROM1
2 stores a control program for an origin return operation described later.

An SRAM or the like is used for the RAM 13, and temporary calculation data, display data, input / output signals, etc. are stored therein. The non-volatile memory 14 uses a CMOS backed up by a battery (not shown), and stores parameters, machining programs, tool correction data, pitch error correction data and the like that should be retained even after the power is turned off.
The parameters stored in the non-volatile memory 14 include a grid shift amount and a positional shift amount, which will be described later.

The CRT / MDI unit 20 is arranged on the front surface of the numerical controller or at the same position as the machine operation panel.
Used to display data and graphics, input data, and operate numerical control equipment. The graphic control circuit 21 converts a digital signal such as numerical data and graphic data into a raster signal for display and sends the raster signal to the display device 22, and the display device 22 displays these numerical values and graphics. CR on the display device 22
A T or liquid crystal display device is used.

The keyboard 23 is composed of numerical keys, symbolic keys, character keys and function keys, and is used for creating and editing a machining program and operating the numerical control device. The software key 24 is provided below the display device 22, and its function is displayed on the display device. When the screen of the display device changes, the function of the software key changes corresponding to the displayed function.

The axis control circuit 15 receives the axis movement command from the processor 11, and outputs the axis movement command to the servo amplifier 16
Output to. The servo amplifier 16 amplifies this movement command and drives a servo motor coupled to the machine tool 30,
It controls the relative motion of the tool and the work of the machine tool 30. The machine tool 30 is a machine tool having a master axis and a slave axis. The axis control circuit 15 and the servo amplifier 16
Are provided in a number corresponding to the number of axes of the servo motor.

A PMC (Programmable Machine Controller) 18 is M from the processor 11 via the bus 19.
Receives (auxiliary) function signal, S (spindle speed control) function signal, T (tool selection) function signal, and the like. Then, these signals are processed by a sequence program, and output signals are output, and pneumatic equipment, hydraulic equipment in the machine tool 30,
Controls electromagnetic actuators, etc. Also, the machine tool 30
In response to the signals from the machine control panel inside, such as button signals, switch signals and limit switches, sequence processing is performed,
The necessary input signals are transferred to the processor 11 via the bus 19.

In FIG. 2, the spindle motor control circuit, the spindle motor amplifier, etc. are omitted. In the above example, the number of processors 11 is one, but
It is also possible to use multiple processors in a multiprocessor configuration.

Next, a specific procedure of the origin return control of this embodiment will be described. FIG. 3 is a block diagram showing the function of origin return control of this embodiment. Numerical control unit (CNC)
A distribution pulse for instructing the movement amount of the master axis is input to the master axis side arithmetic unit 41 of 10. Error register 4
A distribution pulse is input to 3 via the arithmetic unit 42. The servo amplifier 16a outputs an output voltage according to the error amount of the error register 43, drives the servo motor 46, and controls the movement of the master axis.

The servo motor 46 incorporates a pulse coder (not shown), and the position feedback pulse of this pulse coder is fed back to the calculator 42. Also, each time the grid of the pulse coder rises, the grid signal is sent to the reference counter 44. The reference counter 44 counts the output of the arithmetic unit 41 and resets the count value each time a grid signal is input. Further, the reference counter 44 sends this reset signal to the axis stop control means 45, 55.

When a reset signal is sent from both the reference counter 44 and a reference counter 54, which will be described later, the axis stop control means 45 stops the output of the arithmetic unit 41 and controls the movement of the master axis.

On the other hand, a distribution pulse for instructing the movement amount of the slave axis is input to the arithmetic unit 51 on the slave axis side.
The distribution pulse is input to the error register 53 via the calculator 52. The servo amplifier 16b outputs an output voltage according to the error amount of the error register 53, drives the servo motor 56, and controls the movement of the slave axis.

The servo motor 56 has a built-in pulse coder (not shown), and the position feedback pulse of this pulse coder is fed back to the calculator 52. Also, each time the grid of the pulse coder rises, the grid signal is sent to the reference counter 54. The reference counter 54 counts the output of the arithmetic unit 51 and resets the count value every time a grid signal is input. Further, the reference counter 54 sends this reset signal to the axis stop control means 45, 55.

When the reset signals are sent from both the reference counter 44 and the reference counter 54, the axis stop control means 55 stops the output of the arithmetic unit 51 and controls the movement of the slave axis.

When the axis shift control means 45 and 55 detect that both the master axis and the slave axis have stopped, the position shift amount calculation means 60 reads the count values of the reference counters 44 and 54 and the grid position of each axis. The positional shift amount Xa is calculated. The calculated position shift amount Xa is used as the origin return control means 5 for the slave axis.
No. 7 memory unit 57b is set with parameters.

FIG. 4 is a diagram showing a method of calculating the positional deviation amount Xa by the positional deviation amount calculating means 60. First, when the axis movement is started and the grid Ga of the master axis rises first, and then the grid Gb of the slave axis rises, when the latter grid Gb of the slave axis rises, the axis stop control means 45, 55 causes A stop command for movement of each axis is issued. Then, when both the master axis P1 and the slave axis P2 are stopped, the position shift amount calculation means 60 reads the shift amounts Md and Sd of the respective axes, and calculates the position shift amount Xa = Sd-Md of the grid position. To do.

Returning to FIG. 3, the origin-returning operations of the master axis and slave axis are performed by origin-returning control means 47 and 5, respectively.
Performed by 7. A preset grid shift amount GS is stored in the memory unit 47b of the origin return control means 47. When the origin return operation is started, the axis stop control means 47a monitors the count state of the reference counter 44, receives a reset signal from the reference counter 44, and confirms the grid position of the master axis. The output of the computing unit 41 is stopped in the state of being shifted by the amount GS, and the movement of the master axis is stopped. As a result, the master axis is returned to the origin.

On the other hand, the memory unit 5 of the origin return control means 57.
A value obtained by adding the positional shift amount Xa to the preset grid shift amount GS is stored in 7b. When the origin return operation is started, the axis stop control means 57a monitors the count state of the reference counter 54, receives a reset signal from the reference counter 54, and confirms the grid position of the slave axis. The output of the computing unit 51 is stopped in a state of being shifted by the amount GS + the positional deviation amount Xa, and the movement of the slave axis is stopped. As a result, the slave axis can be returned to the origin by matching the grid position of the master axis with the grid position of the slave axis.

FIG. 5 is a flow chart showing the procedure for calculating the positional deviation amount Xa. It should be noted that this flowchart is executed when the calculation mode of the positional deviation amount Xa is set by the parameter. [S1] The movement control of the master axis and the slave axis is performed. [S2] It is determined whether or not the grids of the master axis and the slave axes have risen, and if they have risen, the process proceeds to step S3, and if not, the process returns to step S1. [S3] The movement of the master axis and the slave axis is stopped and controlled. [S4] The positional deviation amount Xa is calculated and parameters are set.

As described above, in this embodiment, the positional deviation amount Xa between the grid positions of the master axis and the slave axis is automatically calculated, and the origin return operation of the slave axis is performed based on this positional deviation amount Xa. Therefore, the work of setting the data for return to origin can be simplified.

[0031]

As described above, according to the present invention, when each grid of the master axis and slave axis rises, the movement of each axis is stopped and controlled, and the positional deviation amount of the grid position of each axis at that time is controlled. Is calculated and stored, and for the slave axis, the origin return operation is performed based on the value obtained by adding the grid shift amount and the position shift amount.
It is possible to simplify the work of setting the data for return to origin.

[Brief description of drawings]

FIG. 1 is a diagram showing a concept of functions of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of hardware of a numerical controller according to the present invention.

FIG. 3 is a block diagram showing a function of origin return control of the present embodiment.

FIG. 4 is a diagram showing a method of calculating a positional deviation amount by a positional deviation amount calculating means.

FIG. 5 is a flowchart showing a procedure for calculating a positional deviation amount.

[Explanation of symbols]

 1 axis movement command means 2 axis stop control means 3 master axis 4 slave axis 5 position deviation amount calculation means 6 position deviation amount storage means 8 origin return control means 10 numerical controller (CNC) 12 ROM 14 non-volatile memory 15 axis control circuit 16 Servo amplifier 30 Machine tool

Claims (2)

[Claims] 1. A numerical controller for performing origin return of a master axis and a slave axis by a grid method, wherein axis movement command means for instructing movement of each axis of the master axis and slave axis, and each of the master axis and slave axis. Axis stop control means for stopping and controlling the movement of the master axis and the slave axis when the grid rises together, and a position for calculating the amount of positional deviation of the grid position of each axis when the master axis and the slave axis stop moving. Deviation amount calculating means, position deviation amount storing means for storing the calculated position deviation amount, and for the master axis, the origin return operation is performed based on a preset grid shift amount, and for the slave axis, , A home-return control hand that performs the home-return operation based on a value obtained by adding the grid shift amount and the position shift amount. Numerical control apparatus characterized by having, when. 2. The numerical control device according to claim 1, wherein the position shift amount storage means is stored by parameter setting.