JPH03254Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) This invention relates to a device that detects overtravel in a movable part of a machine tool, stops and locks it, and then releases the overtravel.

(Prior Art) For example, a turret punch press as an example of a machine tool includes a movement positioning device that appropriately moves a workpiece in the X and Y axis directions and positions it with respect to a processing section, and a drive control device for the movement and positioning device. A drive control device is provided.

This drive control device may cause the movement positioning device to move beyond a predetermined movement range (hereinafter referred to as overtravel) and place an excessive burden on the motor.
A stop/lock circuit is provided to prevent damage to any part of the machine. This stop/lock circuit, for example, stops and locks the movement of the axis when it detects that the movable positioning device has reached the end of its stroke, and displays overtravel.

The drive control device is also provided with an overtravel release circuit (hereinafter referred to as an OT release circuit) in order to enable automatic operation of the overtravel moving positioning device again. This OT release circuit is used, for example, after pressing the overtravel release button to enable manual operation of the mobile positioning device.
A manual operation button is operated to return the movable positioning device from the stroke end to a position where automatic operation is possible.

However, in such a drive control device, when releasing the overtravel, great care must be taken not to operate the operation button in the opposite direction to the OT release direction, which is very troublesome. It was hot. Additionally, if the manual operation button is pressed in the opposite direction by mistake, the moving positioning device may move beyond the stroke end, placing an excessive burden on the motor or possibly damaging various parts of the machine. There was a problem.

[Purpose of invention]

The purpose of this invention is to solve the problems of the conventional technology, and to provide a device that does not accidentally drive the movable part of a machine tool in the opposite direction to the release direction when releasing overtravel. That's true.

[Summary of the idea]

To achieve the above object, this invention includes a drive motor for moving a movable part of a machine tool along a guide part, an area sensor for determining an overtravel area of the movable part on the guide part, and a drive motor for moving a movable part of a machine tool along a guide part; It has a stop/lock circuit that stops and locks the operation of the movable part when the sensor detects an operation, and a lock release switch that releases the lock of the stop/lock circuit, and receives an appropriate input signal including a release signal of the release switch. , an overtravel release circuit that releases the lock of the stop/lock circuit and moves the stopped/locked movable part only in the overtravel release direction by referring to the detection signal of the area sensor; This prevents the movable part of the machine tool from being erroneously driven in the opposite direction to the release direction when releasing overtravel.

[First Embodiment] Hereinafter, a first embodiment of this invention will be described with reference to FIGS. 1 to 3. Fig. 1 is a perspective view of a turret punch press as an example of a machine tool equipped with this embodiment, Fig. 2 is a block explanatory diagram of this embodiment, and Fig. 3 is a processing flow showing the operation of this embodiment. It's a chat.

Referring to FIG. 1, a turret punch press 1 as an example of a machine tool rotatably supports upper and lower turrets 7 on which a number of molds 5 are mounted, and a turret 7 mounted above the molds 5. Striker 9 in place
is provided. Then, by rotating the turret 7, a suitable mold 5 is struck by the striker 9.
After indexing the workpiece to a lower position and appropriately positioning the workpiece 11 between the upper and lower turrets 7, punching is performed on the workpiece 11 by striking the workpiece 11 with the striker 9. . Therefore, the lower position of this striker 9 constitutes a processing section.

In order to position the workpiece 11 with respect to this processing section, the turret punch press 1 is provided with a moving positioning device 13. That is, Y-axis guide rails 15 extending in the Y-axis direction are provided on both sides of the lower part of the frame 3. A table 21 is movably supported.
This carriage base 19 is the Y-axis guide rail 1
The carriage base 19 extends in the X-axis direction perpendicular to the workpiece 11.
A plurality of work clamps 23a, 23 that can freely grip
A carriage 25 is supported to be movable in the X-axis direction.
Further, the movable table 21 and the carriage 25 are each provided with an appropriate drive motor via an appropriate drive shaft (neither is shown in FIG. 1; see FIG. 2).

Therefore, the workpiece 11 held by the workpiece clamps 23a and 23b is moved to the movable table 2.
1 in the Y-axis direction, and move the carriage 2
5 in the X-axis direction, X,
It is moved appropriately in the Y-axis direction and positioned appropriately with respect to the processing section.

Such a movable table 21 and carriage 2
In order to drive and control the turret punch press 5, the turret punch press 1 is provided with a drive control device shown in FIG. However, in FIG. 2, for the sake of simplicity, a stop/stop function is used to prevent the movable table 21 or the carriage 25 from accidentally moving beyond the stroke end when positioning the workpiece 11.
Only the lock circuit and related circuits are shown.
Further, although only the structure of the drive control device related to the carriage 25 is shown, the structure of the drive control device related to the movable table 21 is also exactly the same. In addition, in Figure 2,
Drive shaft for driving the aforementioned carriage 25
Cx, drive motor Mx are shown.

Overtravel limit switches (OT limit switches) 27a and 27b for detecting overtravel of the carriage 25 are provided near both ends of the carriage base 19. Therefore,
When the carriage 25 attempts to move beyond the stroke Lx, the OT limit switch 2
7a and 27b perform a detection operation. The detection signals of these OT limit switches 27a and 27b are
9 to the stop/lock circuit 31. This stop/lock circuit 31 stops and locks the operation of the drive shaft Cx and the carriage 25 upon receiving the detection signals from the OT limit switches 27a and 27b.

Therefore, when the carriage 25 reaches the stroke end, it is stopped at the stroke end position by the action of the stop/lock circuit 31.

Although not shown, for safety reasons, the stop/lock circuit 31 stops not only the operation of the carriage but also all moving parts of the machine upon receiving the detection signal from the OT limit switches 27a and 27b.・Lock it.

On the other hand, in order to cancel the overtravel,
The drive control device is provided with an overtravel release circuit consisting of an overtravel release switch (OT release switch) 39, a manual operation button 41, an I/O 43, and a manual operation signal determination section 45.

The OT release switch 39 releases the lock of the carriage 25 etc. by the stop/lock circuit 31. That is, when the OT release switch 39 is turned on, the manual operation signal inputted from the manual operation signal determining section 45 is stopped and locked in the stop/lock circuit 3.
1 to the output unit 35.

The manual operation button 41 is for manually operating the carriage 25, and a manual operation signal generated by this operation is output to the manual operation signal determination section 45 via the I/O 43.

Upon receiving the manual operation signal, the manual operation signal determining section 45 selects the OT limit switch 27a,
By referring to the detection signal from 27b, it is determined whether the manual operation signal correctly moves the carriage 25 in the overtravel release direction, and if the manual operation signal moves the carriage 25 in the opposite direction to the release direction. This makes the manual operation signal invalid.

Note that the output section 35 and I/O 37 output appropriate carriage drive signals to the drive motor Mx.

Next, the case where the drive control device is used to actually release the overtravel of the carriage 25 will be described with reference to FIG. 3. However, it is assumed that the carriage 25 is overtraveled at the left end of the carriage base 19, as shown in FIG. 2, at the start of the operation.

When OT release is started in step 301 and the OT release switch 39 is turned on in step 302, the stop/lock circuit 31 is unlocked and manual operation becomes possible.

Therefore, in step 303, manual operation button 4 is pressed.
1 and perform appropriate manual operations. When the operation signal resulting from this manual operation is input to the manual operation signal determination section 45 via the I/O 43, step 30 is performed.
In step 4, the manual operation signal determination unit 45 refers to the detection signals from the OT limit switches 27a and 27b and determines whether the manual operation signal correctly moves the carriage 25 in the OT release direction. . If the carriage 25 is to be moved in the opposite direction to the OT release direction by mistake, select "NO" and proceed to step 309 to invalidate the manual operation signal.
This process ends at step 310.

On the other hand, in step 304, if the manual operation signal is to move the carriage 25 in the OT release direction, select "YES" and proceed to step 3.
Proceed to 05.

When the manual operation signal is transmitted from the manual operation signal determining section 45 to the lock/stop circuit 31 in step 305, it is determined in step 306 whether or not the OT release switch 39 is reliably turned on, that is, the stop/lock circuit 31 is turned on. It is determined whether or not the lock of the circuit 31 is released. If the lock is released, "YES" is selected and the process proceeds to step 307.

In step 307, the manual operation signal is sent from the stop/lock circuit 31 to the output section 35 and the I/O 3.
7 to the drive motor Mx.

Then, in step 308, the carriage 25 is moved in the OT release direction (to the right in FIG. 2) via the drive motor Mx and shaft Cx to release the overtravel.
Finish the OT release process.

Note that if the manual operation button 41 is operated without turning on the OT release switch 39, "NO" is selected in step 306, and the process proceeds to step 309.
Since the manual operation signal is invalidated, OT release is not performed.

Therefore, according to this embodiment, when manually releasing overtravel, even if an attempt is made to operate the carriage in the opposite direction to the OT release direction, the manual operation signal is invalidated, so no malfunction occurs. Therefore, excessive load on the drive motor and damage to various parts of the machine can be prevented.

Furthermore, in this embodiment, the OT release direction is determined based on the detection signal from the existing OT limit switch without providing a special overtravel release sensor, which reduces the number of parts and simplifies the configuration. be able to.

In addition, in the above embodiment, the carriage 25
Although the present invention is not limited to this, for example, the work clamps 23a, 2 provided on the carriage 25 have been described.
3b is moved on the carriage 25 by an appropriate driving means, the workpiece clamps 23a, 2
It can also be applied to the case of preventing "falling off" of the cartridge 3b from the carriage 25. That is,
In this case, for example, limit switches for detecting the work clamps 23a and 23b are provided at both ends of the carriage 25, and this detection signal is input to the I/O port 29 in the block diagram of FIG. It is possible to prevent overtravel (“falling off”) of the workpiece clamps 23a, 2 when the overtravel is released.
3b can be prevented from malfunctioning.

Furthermore, a plurality of work clamps 23a, 23b
When a plurality of workpiece clamps move on the carriage 25, an approach detection limit switch is provided to detect the approach of the plurality of workpiece clamps to each other, and a detection signal of this limit switch is input to the I/O 29 of the device. It is possible to prevent collisions between individual work clamps, and also to prevent malfunctions when separating work clamps that have stopped in a close state.

[Second Example] Next, regarding the second example of the present invention, the fourth example
This will be explained with reference to FIGS. FIG. 4 is a block diagram illustrating the present embodiment provided in the turret punch press of FIG. 1, and FIG. 5 is a processing flowchart for automatically canceling overtravel according to the present embodiment.

Referring to FIG. 4, in this embodiment, in order to detect overtravel of the carriage 25 and movable table 21, carriage OT limit switches 27a, 27b and movable table OT limit switches 47a, 47b are provided, respectively. Therefore, when the carriage 25 moves beyond the stroke Lx, it becomes overtravel, and when the movable table 21 moves beyond the stroke Ly,
This results in overtravel.

These are the carriage OT limit switch 27.
When the movable table OT limit switches 47a, 27b or the movable table OT limit switches 47a, 47b are detected, the detection signal is input to the stop/lock circuit 31 via the I/O 29, and by the action of the stop/lock circuit 31, the movable table 21 and Carriage 25 stopped,
The locking is the same as in the first embodiment.

In order to automatically cancel this overtravel, this embodiment includes an OT automatic cancel button 49, an I/O 43,
An overtravel cancellation circuit is provided which includes an OT axis/OT direction judgment section (overtravel position judgment section) 51, an axis movement signal generation section (overtravel cancellation signal generation section) 53, and an OT cancellation switch section 57.

The OT automatic cancellation button 49 is a start button for starting automatic overtravel cancellation.

The OT axis/OT direction determining section 51 is activated by a start signal of the OT automatic release button 49 inputted via the I/O 43, and is activated by the start signal of the OT automatic release button 49 inputted via the I/O 43,
Based on the detection signals from the OT limit switches 47a and 47b, it is determined which axis is overtravelling and in which direction.

The axis movement signal generation section 53 generates a correct axis movement signal for automatically canceling overtravel based on the judgment signal from the OT axis/OT direction judgment section 51.

Further, the OT release switch section 57 is activated by the ON signal from the OT automatic release button 49, the lock of the stop/lock circuit 31 is released, and the axis movement signal from the axis movement signal generation section 53 is outputted. 3
5.

Next, the process of automatically canceling overtravel using the second embodiment will be described with reference to FIG. However, at the start of operation, the drive shaft
It is assumed that either Cx or Cy (that is, the carriage 25 or the movable table 21) has overtraveled and the machine operation is stopped and locked.

When automatic OT cancellation is started in step 501, the OT automatic cancellation button 49 is first turned on in step 502.

Then, in step 503, the OT axis/OT direction determining section 51 determines the drive shaft that has overtraveled and the direction of the overtravel based on the detection signals from the carriage OT limit switches 27a, 27b or the movable table OT limit switches 47a, 47b. The judgment result is output to the axis movement signal generation section 53.

In step 504, the axis movement signal generation section 53
Based on the judgment signal from the OT axis/OT direction judgment section, a correct axis movement signal for automatic OT cancellation is created. That is, for example, when the carriage 25 overtravels at the left end of the carriage base 19 in FIG. 4, an axis movement signal is created to move the carriage 25 to the right,
Also, for example, the movable table 21 in FIG.
When overtravel occurs at the lower end of the Y-axis guide rail 15, an axis movement signal is generated to move the movable table 21 upward.

Next, the axis movement signal created above is processed in step 5.
When the signal is transmitted to the stop/lock circuit 31 in Step 505, the stop/lock circuit 31 determines whether the OT release switch section 57 is on (that is, whether the lock of the stop/lock circuit is released or not). ), and if it is on, “YES”
is selected, and in step 507, the axis movement signal is output to the drive motor Mx or My. Then, in step 509, the drive motor Mx or My is set to a predetermined value.
When the OT axis is moved in the OT release direction, step 5
At step 10, this OT automatic cancellation process ends.

Note that, similar to the first embodiment, step 50
If the OT release switch 57 is not turned on for some reason in step 6, select "NO" and
In step 509, the automatically generated axis movement signal is invalidated and the automatic OT cancellation is canceled.

Further, as shown in FIG. 4, for example, when both the carriage 25 and the movable table 21 are overtraveled, a signal from the OT axis/OT direction determining section 53 is sent to the axis movement signal generating section 53.
creates axis movement signals to sequentially release axes Cx and Cy from overtravel. Then, this axis movement signal is sent to the stop/lock circuit 31, the output section 35,
The signal is output to the drive motors Mx and My through I/037, and the axes Cx and Cy, the carriage 25, and the movable table 21 are sequentially released from overtravel.

Therefore, according to this embodiment, the carriage 25,
Even if one or both of the movable table 21 and the movable table 21 become overtraveled, the overtravel can be automatically and reliably canceled simply by turning on the OT automatic cancellation button 49.

In the above embodiment, no other operations were performed when overtravel was automatically canceled, but it is not necessary to do so; for example, each axis may be returned to its origin at the same time. You can also do it. In this way, the next work can be executed immediately after overtravel is released.

[Effect of idea]

As can be understood from the description of the embodiments above, the overtravel detection and cancellation device for the movable part of a machine tool of this invention is capable of accidentally moving the movable part of the machine tool in the opposite direction to the overtravel release direction when canceling overtravel. Since the machine is not driven at all, there is no risk of putting an excessive load on the drive motor or damaging the movable parts of the machine.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a turret punch press as an example of a machine tool equipped with the first and second embodiments of the present invention, FIG. 2 is a block diagram of the first embodiment, and FIG. 3 is a processing flowchart when overtravel is canceled using the first embodiment, FIG. 4 is a block explanatory diagram of the second embodiment, and FIG. 5 is a processing flow chart when overtravel is canceled using the second embodiment. This is a processing flowchart for automatically canceling overtravel. 31...Stop/lock circuit, 39...OT release switch, 41...Manual operation button, 45...Manual operation signal judgment section, 49...OT automatic release button, 51...OT axis/OT direction judgment section, 53...
Axis movement signal generation section, 57...OT release switch section.

Claims (1)

[Claims for Utility Model Registration] (1) A drive motor that moves a movable part of a machine tool along a guide part, an area sensor that defines an overtravel area of the movable part on the guide part, and a drive motor that moves a movable part of a machine tool along a guide part; It has a stop/lock circuit that stops/locks the operation of the movable part when the sensor detects an operation, and a lock release switch that releases the lock of the stop/lock circuit, and an appropriate input signal including a release signal from the release switch. in,
An overtravel release circuit that releases the lock of the stop/lock circuit and moves the stopped/locked movable part only in the overtravel release direction by referring to the detection signal of the area sensor. Features: Overtravel detection and release device for moving parts of machine tools. (2) The overtravel release circuit includes a manual operation button that manually moves the movable part, and a manual operation signal from the manual operation button that causes the stopped/locked movable part to move correctly in the overtravel release direction. a manual operation signal determination unit that determines whether the command is erroneously moved in a direction opposite to the release direction based on a detection signal from the area sensor and invalidates the command if the command is erroneously moved in a direction opposite to the release direction. An overtravel detection and cancellation device for a movable part of a machine tool as set forth in claim 1. (3) The overtravel release circuit includes an overtravel position determination unit that determines which movable part has reached an overtravel area among the plurality of movable parts and the overtravel direction thereof based on the detection signal of the area sensor; The present invention is characterized by comprising an overtravel cancellation signal creation section that creates an overtravel cancellation signal for moving the movable part that has reached the overtravel region in the overtravel cancellation direction based on the judgment signal from the judgment section. A device for detecting and canceling overtravel of a movable part of a machine tool as set forth in Claim 1 of the Utility Model Registration Claim.