JPH0619520A - Numerically controlled machine tool equipped with abnormal power source countermeasure control - Google Patents

Abstract

PURPOSE:To suppress the capacity of a uninterruptive power unit small and prevent respective parts of the machine tool from being damaged. CONSTITUTION:The uninterruptive power unit 4 always supplies the electric power to a computer device 7 and the control circuit for actuator driving devices 10 and 12. A feed device and actuators 11 and 13 for tools can avow a momentary power failure, etc., so they are excluded from the load on the uninterruptive power unit 4, whose capacity is reduced. When the abnormality time of the power source is at a level 1 below a 1st set value, the actuators 11 and 13 are placed in a stand-by state and when the abnormality time exceeds the 1st set value and is at a level below a 2nd set value, one machining process is stopped to prude interference at the time of the recovery. When the level exceeding the 2nd set value is reached, data required to restart the machining are stored to guarantee the smooth machining restart at the time of the abnormality recovery.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerically controlled machine tool device for controlling the drive of a machine tool by a computer.

[0002]

2. Description of the Related Art Generally, a numerically controlled machine tool device includes a drive device that drives and controls an actuator of a machine tool, and a computer device that generates a control command for each actuator based on numerical information and outputs the control command to each drive device. It is configured to include. In such a numerically controlled machine tool device, when the power supply voltage of the computer is abnormally lowered due to a momentary power failure or the like, inconveniences such as loss of important data, abnormal operation of control, and abnormal operation of processing machine may occur. Conventionally, in order to protect the numerically controlled machine tool device against such an input power source abnormality, it is generally performed to install an uninterruptible power supply device between the input power source and the numerically controlled machine tool device.

[0003]

However, in the event of a power failure such as a power failure, if an attempt is made to supply sufficient power from the uninterruptible power supply to all the constituent devices constituting the numerically controlled machine tool device, the uninterruptible power supply The capacity has increased,
In particular, when the power capacity of the numerical control device is from KVA to several tens of KVA as the machine tool becomes larger,
The equipment costs a lot.

Therefore, as a method for reducing the capacity of the uninterruptible power supply, conventionally, only the constituent parts of the system of the numerically controlled machine tool device which are particularly sensitive to power supply abnormalities (instantaneous voltage drop / interruption, power failure, etc.) are limited. It has been devised to supply an uninterruptible power supply only to, for example, a control circuit of a drive device for a computer or an actuator.

According to this method, the control circuit of the computer or the driving device can perform the normal operation even when the abnormality of the input power source frequently occurs. However, a control target to which the power of the uninterruptible power supply is not supplied, for example, an actuator of a table feeding device or an actuator of a processing tool such as a cutter may stop. Therefore, the state of the controlled object recognized by the computer or the control circuit may deviate from the actual state.When the power supply abnormality is recovered, the controlled tool such as the work tool abnormally operates, However, there is a problem in that it may be damaged by damaging the machine by interfering with the like.

An object of the present invention is to provide a numerically controlled machine tool device capable of suppressing the capacity of the uninterruptible power supply unit to be small and preventing damage to each part of the machine tool.

[0007]

SUMMARY OF THE INVENTION The present invention includes a drive device for driving and controlling an actuator of a machine tool, a computer device for generating a control command for the actuator based on numerical information and outputting the control command to the drive device, In a numerically controlled machine tool device including a control circuit of a drive device and an uninterruptible power supply device that supplies power to the computer device, a power supply abnormality detection signal is detected by detecting a voltage drop of an input power supply of the uninterruptible power supply device. A power supply abnormality detecting means for outputting, an abnormality time measuring means for measuring the duration of the power supply abnormality based on a power supply abnormality detecting signal output from the means, and a length of the abnormality time output from the abnormality time measuring means. In response to this, an error pair that outputs a retract command and a machining interruption command to a predetermined drive device and stores the data necessary for restarting the machining control when the power supply recovers Characterized in that a control means.

The abnormal time measuring means and the abnormality handling control means can be realized by the contents programmed in advance in the memory of the computer device. Further, the abnormality response control means outputs the save command when the abnormal time is equal to or less than the first set value, and the abnormal time exceeds the first set value and then exceeds the second set value.
It is preferable that the stop command is output when the value is less than or equal to the set value of, and the data is stored when the abnormal time exceeds the second set value.

Further, when the abnormal time does not exceed the second set value after exceeding the first set value, the abnormality handling control means preferably cancels the save command and restarts the numerical control.

[0010]

According to the present invention, by virtue of such construction, the object can be achieved by the following operations.

First, since the uninterruptible power supply constantly supplies power to the control circuits of the computer device and the drive device that cannot tolerate an extremely short-time abnormality such as a momentary power failure, even if a power supply abnormality occurs, a normal function is achieved. In addition, since the required power is relatively small, there is no system problem. On the other hand, the actuator of the work or tool feeding device or the processing device driving device is allowed to be disconnected from the load of the uninterruptible power supply in view of the fact that a short-time abnormality (time less than the first set value) such as momentary power failure can be tolerated. The capacity of the uninterruptible power supply is reduced. In this case, as described above, if the abnormal time becomes long, inconveniences such as interference between the work and the tool occur at the time of power failure recovery, but according to the present invention, the first stage (first setting) in which the power supply abnormality occurs. When the value is less than or equal to), the actuator to be controlled, such as a tool, is retracted, and therefore interference during recovery can be prevented. Further, in the second stage in which the abnormal time exceeds the first set value and is equal to or less than the second set value,
Since one machining process for stopping the actuator to be controlled such as a tool is stopped, it is possible to prevent interference during recovery. In addition, in the third stage when the abnormal time exceeds the second set value, in addition to the correspondence between the first and second stages, necessary data is stored in preparation for the resumption of machining, so that the abnormal Processing can be resumed smoothly when recovered.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall block configuration diagram of an embodiment of a numerical control printed board punching machine according to the present invention. The power supply system of the device of the present embodiment includes a circuit breaker 1 that turns on / off an input power source (AC), a surge killer 2 that removes surges such as a burial, and a three-phase line filter 3 that attenuates noise.
And an uninterruptible power supply 4 and a DC power supply 5. The numerical control printed board drilling machine of the apparatus of this embodiment includes a computer device 7, an operating unit 8 for operating the drilling machine via the computer device 7, and a command unit 9 for inputting various commands to the computer device 7. And a servo motor driving device 10 for driving and controlling the servo motor 11 according to a control command input from the computer device 7, and a spindle motor driving for driving and controlling the spindle motor 13 according to a control command input from the computer device 7. It is configured to include a device 12 and a power supply abnormality detection circuit 14 that detects an abnormality in the input voltage of the uninterruptible power supply 4.

Power for each motor of the servo motor drive device 10 and the spindle motor 12 is supplied from the input side of the uninterruptible power supply device 4. The power supply of the computer device 7, the power supply of the control circuit of the spindle motor drive device 12, and the power supply of the power supply abnormality detection circuit 14 are supplied from the DC power supply device 5. Servo motor drive device 10
The power supply of the control circuit is supplied from the uninterruptible power supply 4.

The power supply abnormality detection circuit 14 is designed to detect an instantaneous voltage drop or interruption of the AC input power supply and output a detection signal converted to a DC level for the time of the power supply abnormality to the computer device 7.

As shown in the block diagram of FIG. 2, the computer system 7 includes a central processing unit (CPU) 7A, a control program registration and data saving memory 7B, and a power supply abnormal time measuring circuit 7C. It is configured. The power supply abnormality time measurement circuit 7C takes in a power supply abnormality detection signal output from the power supply abnormality detection circuit 14, measures the duration of the power supply abnormality (abnormal time), and has three levels set according to the width of the abnormal time. CPU 7 divided into (level 1, 2, 3)
It is converted into an electric signal that can be read by the input / output (I / O) unit of A and output. In this embodiment, the level 1 is set to 200 ms or less, the level 2 is set to more than 200 ms and 500 ms or less, and the level 3 is set to 500 ms or more.

The CPU 7A includes an abnormality handling control means according to the characteristic part of the present invention. This abnormality response control means fetches an abnormality detection signal via the I / O control section,
In the case of level 1, it is judged that the power supply has been momentarily cut off, and the tool or the like to be controlled is temporarily saved from the work to be processed. In the case of level 2, the numerical controller is stopped single and the machining is suspended. Here, the single stop means stopping one machining process which is currently being executed among a series of machining processes. When the level 3 signal is output, it is determined that there is a power failure, the level 1 and 2 processes are performed, and then various data necessary for resuming machining after the power failure is restored are stored in the memory unit. This data refers to data required when reprocessing continues due to processing interruption. When only the level 1 signal is not output and the level 2 signal is not output, the temporary saving of the controlled object from the workpiece, which is the object to be processed, is canceled and the machining is restarted.
These series of controls are realized by the CPU 7A executing a program stored in the memory 7B in advance.

[0017]

As described above, according to the present invention,
Even if an abnormality occurs in the input power source, it is possible to protect the processing target and the machine, and to smoothly restart the processing after the processing is interrupted, which is effective in preventing a reduction in the equipment operating rate.

[Brief description of drawings]

FIG. 1 is a block diagram of a numerical control printed board punching machine according to an embodiment of the present invention.

FIG. 2 is an internal block diagram of the computer device shown in FIG.

[Explanation of symbols]

 1 Circuit Breaker 2 Surge Killer 3 3 Phase Line Filter 4 Uninterruptible Power Supply 6 DC Power Supply 7 Computer 7A CPU 7B Memory 7C Instantaneous Power Failure Time Measurement Circuit 8 Operation Section 9 Command Section 10 Servo Motor Drive 11 Servo Motor 12 Spindle Motor Drive device 13 Spindle motor 14 Abnormal time measurement circuit

Claims (3)

[Claims] 1. A drive device for driving and controlling an actuator of a machine tool, a computer device for generating a control command for the actuator based on numerical information and outputting the control command to the drive device, a control circuit for the drive device, and the computer. In a numerically controlled machine tool device including an uninterruptible power supply device for supplying power to the device, a power supply abnormality detection means for detecting a voltage drop of an input power supply of the uninterruptible power supply device and outputting a power supply abnormality detection signal, Abnormal time measuring means for measuring the duration of the power abnormality based on the power abnormality detection signal output from the means, and a predetermined drive according to the length of the abnormal time output from the abnormal time measuring means A special feature is that the device is equipped with an abnormality response control means that selectively outputs a retract command and a machining interruption command, and stores the data necessary for restarting the machining control when the power supply recovers. Numerically controlled machine tool equipment. 2. The abnormal response control means according to claim 1, wherein the abnormal command is output when the abnormal time is less than or equal to the first set value, and the abnormal time exceeds the first set value and the second set value is exceeded. A numerically controlled machine tool device, wherein the stop command is output in the following cases, and the data is stored when an abnormal time exceeds a second set value. 3. The method according to claim 2, wherein when the abnormal time exceeds the first set value and does not exceed the second set value, the save command is canceled and drive control is restarted. Numerically controlled machine tool equipment.