JPH07319519A - Spindle control method for multi-axis numerical controller - Google Patents

Abstract

(57) [Abstract] [Purpose] In the spindle control method of multi-axis numerical control device,
When a plurality of sets of rotary spindles to be synchronously controlled are set, rotation control is independently performed between the sets. Rotation control in which the rotation ratio is different between the rotation main shafts that are synchronously controlled is performed. [Configuration] In a spindle control method for a multi-axis numerical control device,
A step of setting the rotational speeds and accelerations of a plurality of rotating spindles independently, and a set of rotating spindles for performing synchronous control between the rotating spindles, and a step of performing synchronous control for each set of rotating spindles, Changing at least one of a rotation speed and an acceleration of an arbitrary rotary spindle in a set of rotary spindles for which synchronous control is performed. When a set of rotary spindles that perform synchronous control at different stages is set, synchronous control is performed between both rotary spindles in the set set of rotary spindles, and synchronous control is performed between the set of rotary spindles. Absent. Rotation control can be performed independently on a single rotation spindle that is not set as a set of rotation spindles that perform synchronous control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle control method for a multi-axis numerical controller. In particular, the present invention relates to a spindle control method for a multi-axis numerical control device in which an arbitrarily set rotary spindle among a plurality of rotary spindles is synchronously controlled at a predetermined rotation ratio.

[0002]

2. Description of the Related Art The rotary spindles of a plurality of drive motors mounted on a numerically controlled machine tool (NC machine tool) are controlled by a multi-axis numerical controller. This multi-axis numerical control device employs a spindle control method in which both of the plurality of rotary spindles selected in relation to the master axis and the slave axis are synchronously controlled at a predetermined rotation ratio.

For example, Japanese Laid-Open Patent Publication No. 4-238504 discloses a spindle control method for a multi-axis numerical control apparatus in which a plurality of rotary spindles are individually controlled to rotate and a plurality of rotary spindles are rotationally controlled in synchronization with each other. Is disclosed. In the disclosed spindle control method, independent rotation control and synchronous rotation control are switched by a program stored in the multi-axis numerical control device. When synchronous rotation control is performed, all of the rotating spindles that perform the rotating operation are set to the same rotation speed.

[0004]

However, the following points have not been taken into consideration in the spindle control method of the above-disclosed multi-axis numerical control device.

First, because synchronous rotation control is performed on all the rotary spindles that perform rotary motion, a plurality of sets (synchronous pairs) of rotary spindles to be synchronously controlled are set, and the set rotary spindles are set. The rotation control cannot be performed independently between the groups.

Secondly, for the same reason, the rotation control in which the rotation ratio, for example, the rotation speed, is different between the synchronously controlled rotating main shafts cannot be performed.

Third, to realize the above rotation control, 2
More than one multi-axis numerical control device is required. For this reason, the NC machine tool including the multi-axis numerical control device becomes large in size, and the equipment cost further increases.

The present invention has been made to solve such problems, and the objects of the present invention are as follows.

Firstly, a spindle control method for a multi-axis numerical control device is provided in which, when a plurality of sets of rotary spindles to be synchronously controlled are set, rotation control can be independently performed between the sets.

Secondly, there is provided a spindle control method for a multi-axis numerical control device capable of performing rotation control with different rotation ratios among the synchronously controlled rotation spindles.

Thirdly, the NC machine tool including the multi-axis numerical control device can be downsized by achieving the first and second objects.
Further, the present invention provides a spindle control method for a multi-axis numerical control device that can reduce equipment costs.

[0012]

In order to achieve the above object, the present invention provides a spindle of a multi-axis numerical control device in which an arbitrarily set rotary spindle among a plurality of rotary spindles is synchronously controlled at a predetermined rotation ratio. In the control method, a step of independently setting the rotational speeds and accelerations of the plurality of rotary spindles, and a set of rotary spindles for performing synchronous control between the plurality of rotary spindles are set, and each of the rotary spindles is set. The present invention is characterized by including a step of performing synchronous control and a step of variably setting at least one of a rotational speed and an acceleration of an arbitrary rotary spindle in a set of rotary spindles on which the synchronous control is performed.

[0013]

In the present invention, the setting of the rotational speeds and accelerations of a plurality of rotary spindles, and the setting of the set of rotary spindles for performing synchronous control are set in different steps. When a set of rotary spindles that perform synchronous control is set at different stages, synchronous control is performed between the rotary spindles (axes in a synchronous pair) in this set of rotary spindles, and between the set of rotary spindles. Synchronous control is not performed between (synchronous pairs). On the other hand, in a single rotating spindle that is not set as a set of rotating spindles for which synchronous control is performed, the rotating speed and the acceleration are independently set in advance, so that the rotating control can be performed independently. Therefore, the rotation control in which the independent rotation control and the synchronous rotation control are mixed can be performed.

Further, when a plurality of sets of rotary spindles to be synchronously controlled are set, rotation control can be independently performed between the sets.

Further, at least one of the rotational speed and the acceleration of the rotary spindle can be changed in the set of rotary spindles subjected to the synchronous control. That is, since the rotational speed and the acceleration can be independently set for each of the rotary spindles, the rotation control can be performed with different rotation ratios among the synchronously controlled rotary spindles.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a system configuration of a multi-axis numerical control device and an NC machine tool according to the present invention. As shown in FIG. 1, the multi-axis numerical controller 1 is connected to a servo amplifier 10, and the servo amplifier 10 is connected to a drive motor 20. The servo amplifier 10 and the drive motor 20 are mounted on the NC machine tool.

The servo amplifier 10 is composed of a plurality of servo amplifiers 11-18. This multiple servo amplifier 1
Each of 1 to 18 and the multi-axis numerical control apparatus 1 are electrically and parallelly connected through a bus cable 7. The bus cable 7 includes an information signal line through which a signal for controlling the rotary spindle of the drive motor 20 is transmitted and received, and a timing signal line (clock signal line) for synchronizing the rotary spindle of the drive motor 20. That is, the plurality of servo amplifiers 11
To 18 are connected to the multi-axis numerical controller 1 to the bus cable 7 respectively.
Through this, the synchronous operation timing signal 6 is input.

The drive motor 20 comprises a plurality of drive motors 2.
1 to 28. The drive motor 21 is connected with the corresponding servo amplifier 11, and the drive motor 22
Is connected to the servo amplifier 12, and so on. The multi-axis numerical control device 1 finally has a drive motor 2
The rotation control of the 0 rotation main shaft is performed.

The multi-axis numerical control apparatus 1 comprises an NC program storage unit 2, an interpreter unit (program conversion section) 3 and a speed pattern calculation task unit 4. The NC program is stored in the NC program storage unit 2. NC in the interpreter unit 3
The NC program stored in the program storage unit 2 is interpreted. In the speed pattern calculation task unit 4, a rotation control command (operation command) for the rotation main shaft of the drive motor 20 is created based on the interpretation of the NC program performed by the interpreter unit 3. The generated rotation control command is transmitted to the servo amplifier 10 through the bus cable 7. Communication by mail 5 is performed between the interpreter unit 3 and the speed pattern calculation task unit 4.

An example of the NC program stored in the NC program storage unit 2 is shown in FIG. The NC program 30 shown in FIG. 2 includes steps 31 to 43.

Step 31 In step 31 of the NC program 30, the rotation spindle of the drive motor 21 is 1000 rpm and the time constant is 50.
Each is set to 0 ms.

Format of each step (data type)
Are basically common and consist of commands and various setting parameters. In step 31, the command is "SP
S ”, and the command“ SPS ”is used for setting the synchronous speed of the rotary spindle. That is, the command "SPS" is used to previously specify the rotational speed, acceleration, and torque when performing the synchronous control. The actual synchronization control is started (updated) when the command "SPC" set in the next step (33) is executed. Also, the command "SPS"
Is used when changing the rotational speeds of a plurality of rotary spindles at the same time, and when changing the rotational speeds of only specific rotary spindles.

As various setting parameters, "rotational spindle number", "rotation speed", "acceleration" and "torque" are set. “Rotation spindle number” as various setting parameters is No. 0 assigned to each of the drive motors 21 to 28.
To No. 7 (see FIG. 1). In step 31, the rotation spindle of the drive motor 21 is designated by inputting No. 0. A number of revolutions per minute (rpm) is input to the "rotation speed" setting. Before the input numerical value, one of a sign "+" (which can be omitted) indicating a normal rotation, a sign "-" indicating a reverse rotation, and a sign "0" indicating a stop is input. A time constant is input to the "acceleration" setting. The time constant is the time required to accelerate to a predetermined rpm. A torque limit value is input to the "torque" setting.

Step 32 In step 32, the rotational spindle of the drive motor 22 is set to 1500 rpm, and the time constant is set to 500 ms.

Step 33 In step 33, the rotary main shaft of the drive motor 21 and the rotary main shaft of the drive motor 22 are set as the synchronous rotary shafts, and the synchronous control is started.

The format is composed of commands and various setting parameters as described above. In step 33, the command is “SPC”, and the command “SPC” is used to set the operation start (update) of the synchronous control for synchronizing the rotation control of the rotary spindle. "Rotation spindle bit", "rotation speed", "acceleration", and "torque" are set as various setting parameters. "Rotation spindle bit" as various setting parameters sets a group of rotation spindles (synchronization pair) for performing synchronous control. This setting is for drive motors 21-
It is carried out by hexadecimal numbers (0 to FF) representing the numbers No. 0 to No. 7 attached to 28. That is, for example, "1" is input when the synchronous control is performed, and "0" is input when the synchronous control is not performed. N in step 33
“1” is input to the bit corresponding to the rotary spindle of the drive motor 21 numbered 0. 0, and “1” is input to the bit corresponding to the rotary spindle of the drive motor 22 numbered No. 1.
Is input, the numerical value “3” is input in hexadecimal. If there is a rotary spindle that is simultaneously set when a bit is first set in a plurality of rotary spindles, the rotary spindles that are simultaneously set are synchronously controlled thereafter. The other parameters such as “rotational speed”, “acceleration” and “torque” are the same as described above.

Step 34 In step 34, the rotational spindle of the drive motor 23 is set to 2000 rpm, and the time constant is set to 300 ms.

Step 35 In step 35, the rotational spindle of the drive motor 24 is set to 2000 rpm, and the time constant is set to 300 ms.

Step 36 In step 36, the rotary main shaft of the drive motor 23 and the rotary main shaft of the drive motor 24 are set as the synchronous rotary shafts, and the synchronous control is started.

Step 37 In step 37, the rotation spindle of the drive motor 25 is set to 500 rpm and the time constant is set to 700 ms, respectively, and the rotation spindle is controlled independently.

Step 38 In step 38, the waiting time until the next step 39 is executed is set to 2000 ms.

Step 39 In Step 39, in order to change the rotational speed of the rotary spindle of the drive motor 21, the rotary spindle is set to 1500.
Targeted to rpm.

Step 40 In step 40, a rotation speed change command for controlling the rotation main shaft of the drive motor 21 is executed at a preset rotation speed.

Step 41 In step 41, the rotation of the rotary spindle of the drive motor 25 is stopped.

Step 42 In Step 42, the waiting time until the next Step 43 is executed is set to 1000 ms.

Step 43 In step 43, the drive motors 21, 22, 23
The rotation of the rotating main shafts 24 and 24 is stopped, and the synchronous control end command for ending the synchronous control is executed.

The above is each step 3 of the NC program 30.
It is an outline of 1-43. FIG. 3 shows the operation patterns of the drive motors 21 to 25 controlled by the NC program 30. As shown in FIG. 3, the rotary main shaft of the drive motor 21, the rotary main shaft of the drive motor 22, the rotary main shaft of the drive motor 23, and the rotary main shaft of the drive motor 24 are all subjected to synchronous control. Or a synchronous axis set) ". The rotation main shaft of the drive motor 25 is independently rotation controlled. Further, the rotation main shaft of the drive motor 21 and the rotation main shaft of the drive motor 22 start synchronous control when the rotation ratio (rotation speed) is different, and the rotation ratio of the rotation main shaft of the drive motor 21 is changed on the way. In this change, the rotation speed of the rotation main shaft of the drive motor 21 is increased (accelerated), and the rotation speed of the rotation main shaft of the drive motor 21 matches the rotation speed of the rotation main shaft of the drive motor 22. On the other hand, the rotary spindle of the drive motor 23 and the rotary spindle of the drive motor 24 are synchronously controlled from beginning to end.

As described above, in the spindle control method for the multi-axis numerical control apparatus according to this embodiment, the rotational speed and acceleration of a plurality of rotary spindles are set, and the set of rotary spindles for synchronous control is set. Set in separate stages. When a set of rotary spindles that perform synchronous control at different stages is set, synchronous control is performed between arbitrary rotary spindles in this set of rotary spindles, and synchronous control is performed between the set of rotary spindles. Absent. On the other hand, the rotation speed and the acceleration are independently set for each of the independent rotating spindles that are not set as a set of rotating spindles for which the synchronous control is performed, so that the rotating control can be performed independently. Therefore, the rotation control in which the independent rotation control and the synchronous rotation control are mixed can be performed.

Further, when a plurality of sets of rotary spindles to be synchronously controlled are set, rotation control can be independently performed between the sets.

Further, in the spindle control method for the multi-axis numerical control apparatus according to the present embodiment, at least one of the rotational speed and the acceleration of an arbitrary rotary spindle can be changed in the set of rotary spindles subjected to the synchronous control. . Rotational speeds and accelerations are independently set for the rotary spindles, and rotation control with different rotation ratios can be performed between the synchronously controlled rotary spindles.

Therefore, in the spindle control method of the multi-axis numerical control apparatus according to this embodiment, N including the multi-axis numerical control apparatus is used.
C Machine tools can be downsized, and equipment costs can be reduced.

Further, in the spindle control method of the multi-axis numerical control device according to the present embodiment, any of the plurality of rotary spindles belonging to one of the rotary spindles that are synchronously controlled is stopped while being synchronized. After that, it is possible to perform independent control or control to newly synchronize with another rotating spindle.

The spindle control method for a multi-axis numerical controller according to the present invention can be applied to, for example, an NC differential preload adjuster that tightens the screws respectively attached to the rotary spindles of both drive motors by the difference in the rotational speeds of the two drive motors. . In the NC differential preload adjuster, first, the tightening torque is measured while the two male and female screws rotate at different rotational speeds. The rotational speed is controlled to zero at the time when the rotational speed difference is gradually eliminated and the prescribed tightening torque is reached, and rotation is stopped without shifting the phase difference between the rotation main shafts of both drive motors. When there is no phase difference between the rotating main shafts of both drive motors when the rotation is stopped, the screws are properly tightened without being overtightened and loosened.

The present invention is not limited to the above-mentioned embodiment, but various modifications can be made without departing from the scope of the invention.

[0046]

According to the present invention, the following effects can be obtained.

First, when a plurality of sets of rotary spindles to be synchronously controlled are set, it is possible to provide a spindle control method for a multi-axis numerical control device capable of independently controlling the rotation between the sets.

Secondly, it is possible to provide a spindle control method for a multi-axis numerical control apparatus that can perform rotation control with different rotation ratios between the rotationally controlled spindles.

Thirdly, the first and second effects are obtained, the NC machine tool including the multi-axis numerical control device can be downsized, and the equipment cost can be reduced. A method can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration of a multi-axis numerical control device and an NC machine tool according to the present invention.

FIG. 2 is a diagram showing an NC program stored in the multi-axis numerical control device.

FIG. 3 is a diagram showing an operation pattern of a drive motor controlled by the multi-axis numerical control device.

[Explanation of symbols]

 1 Multi-Axis Numerical Control Device 2 NC Program Storage Unit 3 Interpreter Unit 4 Speed Pattern Calculation Task Unit 7 Bus Cable 10, 11-18 Servo Amplifier 20, 21-28 Drive Motor 30 NC Program

Claims (1)

[Claims] 1. A spindle control method for a multi-axis numerical control device, wherein a rotation spindle set arbitrarily among a plurality of rotation spindles is synchronously controlled at a predetermined rotation ratio, wherein the rotation speeds of the plurality of rotation spindles are independent of each other. A step of setting an acceleration, a step of setting a set of rotary spindles for performing synchronous control among the plurality of rotary spindles, a step of performing synchronous control for each set of the rotary spindles, and a step of performing the synchronous control of the rotary spindles. A spindle control method for a multi-axis numerical control device, comprising: a step of freely setting at least one of a rotational speed and an acceleration of an arbitrary rotary spindle in a set.