JPH04322303A - Numerical controller - Google Patents

Abstract

PURPOSE:To prevent the damage of a work or working tools at the time of stopping and to safely stop a device by turning on/off the control of plural driving means and brakes in accordance with the order stored in a storage means at the time of detecting the abnormality of the device. CONSTITUTION:When an abnormality detecting part 25 detects the abnormality of the device, a main control part 1 tentatively stops a feed shaft motor 3a by the function generation stop command of a driving unit control on/off commanding part 24. The commanding part 24 reads in the data, which is stored in a memory 27 and indicates a group for which each of motor driving devices 3a to 3d belongs, to determine an object to be processed. Order designation data stored in the memory 27 is read-in to determine the control turning-off order of motor driving devices 3a to 3d and the braking operation order. A driving unit control on/off part 6a turns on an X axis brake 17 and turns off the control of X and Z driving devices 3d and 3c after the lapse of prescribed time in accordance with order designation data. Thus, the X axis brake 17 is operated at such timing that the X axis, namely, a tool post is not naturally dropped.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a numerical control device (hereinafter referred to as
The present invention relates to a driving means (for example, a motor) of an NC device, particularly to control of the motor and brake when the NC device is abnormal.

0002

2. Description of the Related Art A drive device that controls a motor that drives a main shaft of an NC device, a rotary tool, a feed shaft, etc. has a main control section 1, as shown in FIG. , a speed/position command section 2 that commands the speed/position of the motor based on commands from the main control section 1, and a sequence control section 6 that commands control on/off to the motor drive device 3 are connected in parallel. There is. A motor drive device 3 that drives and controls the motor 4 is connected to the speed/position command section 2 and the sequence control section 6, and the motor drive device 3 drives the main shaft, rotary tool, feed shaft, etc. A motor 4 is connected. Furthermore, a detector 5 for detecting the speed and rotational position of the motor 4 is connected to the motor 4, and the output of the detector 5 is fed back to the motor drive device 3.

Next, the operation will be explained. The motor drive device 3 is controlled by a speed/position command section 2 that commands the speed/position of the motor 4 based on commands from the main control section 1, and a sequence control section 6 that commands the motor drive device 3 to turn on/off the control. controlled. Then, as shown in the time chart of FIG. 7, this control on/off command becomes a command ON together with the ON of NC-BUZ indicating that the NC device is operable, and enables control of each drive device. If an abnormality is detected in the control system, it will be turned off to protect the machine and operator. At this time, the motor drive device 3 stops speed/position control by turning off the control signal, and the motor 4 stops free-running or decelerates to a stop.

[0004] Furthermore, there are many NC devices in which the direction of movement of the feed shaft is perpendicular or at an angle (less than 90 degrees) to the vertical plane.

For example, a one-saddle compound lathe as shown in FIG. 8 has a main shaft 9 to which the driving force of a motor 7 is transmitted via a belt 8, and a workpiece 10 is held at the tip of the main shaft 9. A chuck 11 is provided. In addition, the main shaft 9
A tool rest 12 is supported near the tool rest 12 so as to be movable in the X and Z axis directions, and a machining tool 13 and a rotary tool 14 can be mounted on the tool rest 12. The rotary tool 14 is rotationally driven by a rotary tool shaft motor 15 disposed on the tool post 12. Further, the tool rest 12 is moved by a feed shaft motor 16, and movement in the X-axis direction is restricted by a brake 17. In addition, the machining center as shown in FIG. 9 has an L-shaped table and column 1 in side view.
8, a main shaft 9 is supported on the upright portion of the table and column 18 so as to be rotatable and movable up and down, and a machining tool 13 can be fixed to the tip of the main shaft 9. ing. The main shaft 9 is rotationally driven by a main shaft motor (not shown) and is moved up and down by a Z-axis motor 16, and movement in the Z-axis direction is restricted by a mechanical brake 17. ing. Furthermore, Fig. 10 shows the configuration of a two-saddle lathe, and Fig. 11 shows a two-saddle lathe.
A spindle 3-saddle lathe is shown. Note that the same parts as in FIGS. 8 and 9 described above are designated by the same reference numerals, and the description thereof will be omitted.

The X-axis in the one-saddle compound lathe shown in FIG. 8, the Z-axis in the machining center shown in FIG. 9, and the XA-axis and XB-axis in the two-saddle lathe shown in FIG. This is an example of a machine configured with a predetermined angle (less than 90 degrees) on the surface. On these axes,
As mentioned above, when the control of the feed shaft motor drive device is turned off, the motor is no longer able to support the feed shaft, and due to gravity, the upper tool rest in the one-saddle lathe shown in Fig. 8, and the headstock in the machining center shown in Fig. 9 However, in the two-saddle lathe shown in Fig. 10, the upper and lower tool rests fall off. To prevent this,
A mechanical brake 16 is attached to the feed axis that may fall, and when the feed axis control is turned off as shown in the time chart of FIG. 7, the brake is turned on to prevent the fall.

[0007]

[Problems to be Solved by the Invention] By the way, all of the above-mentioned motor drive device control switching operations are performed at the same timing, and the fall prevention brake is also turned on at the same timing. The brake system operates instantly because it is performed only by electrical signal processing, but the brake for preventing falling usually requires several hundred milliseconds for the brake to become effective because it involves mechanical operation. For this reason, there was a problem in that the feed shaft could not be held for several hundred milliseconds when the brake was effective, and it would naturally fall.

For example, in the one-saddle lathe shown in FIG. 8, the X-axis falls, in the machining center shown in FIG. 9, the Z-axis, and in the two-saddle lathe shown in FIG. 10, the XA and XB axes fall, causing the workpiece to be There were problems that caused defects or damage to the processing tools. In addition, the opposed two-spindle three-saddle lathe shown in Fig. 11 can machine two workpieces at the same time, but when an error occurs, all motor drive devices are turned off, so an error occurs in machining one workpiece. When this happens, there is a problem in that both works become defective.

Purpose of the Invention The present invention was made in view of the above-mentioned circumstances, and an object of the present invention is to provide an NC device that can stop damage to workpieces and processing tools safely when the NC device stops abnormally. It's about doing.

0010

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned circumstances, and a numerical control device according to the present invention includes a plurality of drive means for moving a movable part, and a plurality of drive means for regulating the movement of the movable part. An abnormality detection section that detects an abnormality in the brake and the device, a control section that independently turns on/off control of each of a plurality of drive means and brakes, and a control section that turns on/off control of a plurality of drive means and brakes set in advance. and storage means for storing the cutting order. Therefore, the control section:
The present invention is characterized in that when the abnormality detection section detects an abnormality in the device, control of a plurality of drive means and brakes is turned on/off in accordance with the order stored in the storage means.

[0011] Furthermore, it is preferable that the plurality of drive means are classified into control systems, and the drive control of the drive means is turned on/off for each classified control system.

Furthermore, the movable part is a turret, the plurality of driving means are classified into units subordinate to the turret, and drive control of the driving means is turned on/off in units subordinate to the classified turret. You may also do so.

[0013]

[Operation] With the above configuration, the NC according to the present invention
The device stores a preset sequence of turning on/off the control of a plurality of drive means and brakes in a memory means, moves the movable part in a predetermined direction by the plurality of drive means to perform processing, and detects an abnormality when the abnormality detection section is activated. When an abnormality in the apparatus or a processing abnormality is detected, control of a plurality of drive means and brakes is independently turned on/off according to the order stored in the storage means to prevent the movable part from falling.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an NC device, for example, the one-saddle compound lathe shown in FIG. 8 mentioned above. The NC device is
It includes a drive unit order specifying section 22 that specifies the order in which control of a plurality of motors and brakes is turned on/off, and a drive unit combination specifying section 23 that divides the plurality of motors and brakes into desired groups. Specifying section 22 and drive unit combination specifying section 23
A drive unit control on/off command unit 24 is connected to the drive unit control unit 24 as a control means for instructing to turn on/off the control of each of the plurality of motors and brakes independently. The drive unit control on/off command section 24 includes a memory 27 as a storage means for storing a preset order of turning on/off control of a plurality of drive means and brakes, and Abnormality detection unit 25 that detects abnormality
, a main control section 1, a drive unit control on/off section 6a as a control means that independently turns on and off the control of each of the plurality of drive means and brakes, and an X-axis brake control that controls the X-axis brake. 26 is connected. Furthermore,
A speed/position command section 2 that commands the speed/position of the motor based on commands from the main control section 1 is connected to the main control section 1. 6a includes a spindle motor drive unit 3a that drives and controls a spindle motor 7 as a driving means for rotating a spindle as a movable part, and a rotary tool shaft motor 15 that rotates a rotary tool 14 (see FIG. 8). The rotary tool shaft motor drive unit 3b and the tool post 12 as a movable part (Fig. 8
a Z-axis motor drive unit 3c that drives and controls a Z-axis motor 28 as a drive means for moving the Z-axis (see) in the Z-axis direction;
An X-axis motor drive unit 3d that drives and controls the X-axis motor 16 as a drive means for moving the tool rest 12 in the X-axis direction.
are connected. Further, a brake 17 that restricts movement of the tool post 12 in the X-axis direction is connected to the X-axis motor 16, and the brake 17 is controlled by the X-axis brake control section 26.

On the other hand, the order in which the motor and brake control are turned on and off specified by the drive unit order specifying section 22 is, for example, as shown in FIG. There are feed shaft drive devices such as X and Z axes, and the third is a main shaft and rotary tool shaft drive device. Further, the motor and brake groups specified by the drive unit combination specifying section 23 are, for example, shown in FIG.
As shown in the figure, it is classified by control system. and,
The memory 27 stores the order of turning on/off the control of the motor and brake shown in FIG. 3 and the groups of control systems shown in FIG. 4.

Next, the operation of this embodiment will be explained. According to the command from the main control unit 1, the speed/position command unit 2
is each motor, namely the main shaft motor 7 and the rotary tool shaft motor 15.
, generates momentary speed/position commands for the Z-axis motor 28 and the X-axis motor 16, and controls each motor drive device, that is, the main shaft motor drive unit 3a and the rotary tool shaft motor drive unit 3.
b, applied to the Z-axis motor drive unit 3c and the X-axis motor drive unit 3d. Normal machining operations of the NC device are performed in this state.

Next, the operation when the abnormality detection section 25 detects a failure of the NC device or an abnormality in processing will be explained with reference to the timing chart of FIG. 2 and the flowchart of FIG. 5. When the abnormality detection unit 25 detects a failure of the NC device or an abnormality in processing (A in FIG. 2(f)) (step S
1) Determine whether it is necessary to stop the motor (
Step S2). If it is determined that the motor needs to be stopped, the drive unit control on/off command unit 24 commands the main control unit 1 to stop generating functions in order to temporarily stop all feed axes (step S3 ). after that,
The main control unit 1 temporarily stops the feed axis motor based on the function generation stop command, and furthermore, the drive unit control on/off command unit 24
reads the data (see FIG. 4) indicating the group to which each motor drive device belongs, specified by the drive unit combination designation section 23 and stored in the memory 27, and determines the target for subsequent processing (step S4). Further, the order specifying data (see FIG. 3) specified by the drive unit order specifying section 22 and stored in the memory 27 is read (step S
5) Determine the control switching order and brake operation order of each motor drive device. Here, the data in the drive unit order designation section 22 and the drive unit combination designation section 23 are as shown in FIGS. 3 and 4, and the order designation data in FIG.
This means that the control is performed in the following order: axis brake ON → X, Z, C axis drive device control OFF → spindle and rotary tool drive device control OFF. Further, the drive unit combination group designation data in FIG. 4 means that all the drive unit combinations belong to group A in the one-saddle compound lathe of this embodiment.

Then, the drive unit control on/off section 6a turns on the X-axis brake (
Step S6), a predetermined time (t
1) has passed (step S7), the control of the X, Z, and C drive devices is turned off (see FIG. 2(c)) (step S7).
8). Here, timer 1 is set to a sufficient time for the X-axis brake to operate, so the X-axis will be reliably moved by the brake when the "control OFF" command is issued to the X, Z, and C-axis drive devices. is regulated, and will not fall by itself even if the X-axis drive device is turned off. Further, the drive unit control on/off section 6a turns off the control of the spindle and rotary tool drive device after a predetermined time (t2) has elapsed using the built-in timer 2 (step S9) (FIGS. 2(b) and (2)). d)) (step S10), all processes are completed. As described above, when an abnormality occurs, each motor drive device is turned off in a predetermined order, and the X-axis brake is
It can be operated at a time when the shaft will not fall naturally.

If it is determined in step S1 that there is no abnormality, and if it is determined in step S2 that there is no need to stop the motor, the process is immediately terminated. In the above embodiment, a one-saddle compound lathe was explained, but by setting the data in the drive unit combination specifying section 23 for a two-saddle lathe or a two-opposed spindle three-saddle lathe as shown in FIG. It can also be used with machines. However, in these NC devices, there are multiple combination groups as shown in Fig. 4.
The processing from step S6 onward is applied only to the equipment in the group with the abnormality, and the feed axes in other groups remain in a suspended state.

Furthermore, in the opposed two-spindle three-saddle lathe shown in FIG. 11, by performing the axes for which the feed axis function generation is stopped in step S3 in units of groups as shown in FIG. 4, machining of the workpiece of the group in which no abnormality has occurred can be continued. is also possible.

[0021]

[Effects of the Invention] As described above, according to the NC device of the present invention, it is possible to independently turn on/off the control of the motor drive device and turn on/off the brake for holding the driven body when the control is turned off. Therefore, when an abnormality occurs in the NC device, the most suitable stopping method can be selected depending on the machine configuration, and the N can be safely stopped without making the workpiece being machined defective or damaging the machining tool.
C device can be stopped.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a numerical control device according to an embodiment of the present invention.

FIG. 2 is a timing chart showing the operation of this embodiment.

FIG. 3 is a diagram showing order designation data indicating the control order of each device according to the present embodiment.

FIG. 4 is a diagram showing an example of a combination group of drive units according to the present embodiment.

FIG. 5 is a flow chart diagram showing the operation of the present invention.

FIG. 6 is a block diagram showing the configuration of a conventional numerical control device.

FIG. 7 is a timing chart diagram showing a conventional operation.

FIG. 8 is a schematic diagram showing the configuration of a general one-saddle compound lathe.

FIG. 9 is a schematic diagram showing the configuration of a general machining center.

FIG. 10 is a schematic diagram showing the configuration of a general two-saddle lathe.

FIG. 11 is a schematic diagram showing the configuration of a general two-spindle, three-saddle lathe.

[Explanation of symbols]

6a Drive unit control on/off section 7 Main shaft motor 15 Rotary tool axis motor 16 X-axis motor 17 Brake 25 Abnormality detection section 27 Memory 28 Z-axis motor

Claims (3)

[Claims] Claim 1: A plurality of drive means for moving the movable part;
A numerical control device that controls the drive means and the brake, and includes a brake that restricts movement of the movable part, and an abnormality detection section that detects an abnormality in the device, and an abnormality detection section that turns on/off control of each of the plurality of drive means and the brake. and a storage means for storing a preset order of turning on/off control of a plurality of drive means and brakes,
The numerical control device is characterized in that the control section turns on/off control of the plurality of drive means and brakes according to the order stored in the storage means when the abnormality detection section detects an abnormality in the device. 2. The numerical control device according to claim 1, wherein the plurality of drive means are classified into control systems, and drive control of the drive means is turned on/off for each classified control system. . 3. The movable part is a tool post, the plurality of driving means are classified into units subordinate to the tool post, and the drive control of the drive means is turned on/off in units subordinate to the classified tool post. 2. The numerical control device according to claim 1, wherein the numerical control device is operated by: