JPH1185222A - Grinding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to simply set a performance of a grinding wheel stand return at the time of an occurrence of a specific abnormality in a specific condition in a grinding device that starts up the grinding wheel stand return when an ON/OFF condition of each contact point of a sequence circuit satisfies a certain specific condition and to attain versatility. SOLUTION: The device is equipped with a sequence controller 30 that, during working of a work piece or the like, sets to an NC program with M1 and M2 codes whether a condition of a grinding device is effective for start-up of a grinding wheel stand return or not, turns the device on when the current condition of the grinding device is set to the M1 code in which the start-up of the grinding wheel stand return is in effective condition, starts up the grinding wheel stand return when each contact point satisfies the specific condition, turns the device off at this time when the current condition of the grinding device is set to the M2 code in which the start-up of the grinding wheel stand return is not effective, and does not start up the grinding wheel stand return at this time even if each of the contact points satisfies the specific condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding apparatus for processing a workpiece supported by a headstock and a tailstock by a grindstone head.

[0002]

2. Description of the Related Art In order to avoid danger such as breakage of a grinding wheel in a grinding machine, when a specific abnormality occurs in a specific state (during grinding), the current operation is interrupted to forcibly reset the grinding wheel head. The operation of returning to the position is performed. For example, if the rotation of the spindle (workpiece) is stopped during machining of the work piece, the work piece will rotate if the rotating whetstone is in contact with the work piece, causing excessive grinding resistance on the whetstone. The whetstone head is returned to the original position in such a case because the whetstone may be damaged. As a means, a sequence circuit is created to return the grinding wheel head to the original position when a specific abnormality occurs in a specific state, and the grinding wheel head is determined when the sequence controller determines that the conditions are met. A return is made.

[0003]

However, in the prior art, when a certain abnormality occurs in the current state when a certain operation is performed, it is determined whether or not the grinding wheel head needs to be returned.
Since the sequence circuit is created so as to execute the grindstone return when necessary, it has the following problems. a. A sequence circuit must be created each time the target workpiece changes. b. When a new NC program is added or an existing NC program is modified, the grinding wheel head return cannot be executed unless the sequence circuit is recreated. c. However, the sequencer monitors the ON / OFF of the contacts for controlling all operations of the grinding machine, and the number is enormous. Further, since it is not possible to correct the sequence circuit until all of the other parts in the sequence circuit are used, it is very time-consuming.

An object of the present invention is to make it easy to set the execution of the grinding wheel head return when a specific abnormality occurs in a specific state, and to improve versatility.

[0005]

According to a first aspect of the present invention, there is provided a grinding apparatus having a grindstone table for processing a workpiece and turning on and off each contact of a sequence circuit. In a grinding device that activates the wheel head return when the / OFF state satisfies a specific condition, it is determined whether the current state of the grinding device is a state in which activation of the wheel head return is valid or invalid. Setting means for setting, if the current state of the grinding device is set to a state in which the activation of the wheel head return is enabled by the setting means, the wheel head return is performed when each of the contacts meets the specific condition. If the setting means has set the current state of the grinding device to a state in which the activation of the wheel head return is invalid, a sequence controller that does not activate the wheel head return even when the respective contacts satisfy the specific condition. It is characterized in that it comprises and.

According to a second aspect of the present invention, there is provided a grinding apparatus having a grindstone table for processing a workpiece, wherein the ON / OFF state of each contact of a sequence circuit satisfies a specific condition. In the grinding device for activating the grinding wheel head return, setting means for setting whether the current state of the grinding device is in a state in which the activation of the grinding wheel head return is valid or in an invalid state; and Turns on when the state of the grinding device is set to a state in which the activation of the wheel head return is valid. At this time, the wheel head return is activated when each of the contacts satisfies the specific condition. When the state of the grinding device is set to a state in which the activation of the wheel head return is invalid, it has a contact for preventing the wheel head return from being activated even when each of the contacts satisfies the specific condition. Sequence It is characterized in that a controller.

Further, in the above-described grinding apparatus according to the first and second aspects, as described in the third aspect, the current state of the grinding apparatus is a state in which the activation of the grinding wheel head return is valid or invalid. Is set in the NC program.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a grinding machine and its control unit. In FIG. 1, reference numeral 10 denotes a bed, and a traverse table 11 is provided on the bed 10 so as to be able to traverse in the Z-axis direction.

The headstock 1 is mounted on the traverse table 11.
4 and a tailstock 15 facing the headstock 14, and a workpiece W is supported between the headstock 14 and the tailstock 15.

Further, on the bed 10, a grindstone table 16 for rotating and driving a grindstone 17 is provided so as to be movable in the X-axis direction perpendicular to the Z-axis of the traverse table 11 for traverse feed. A grinding fluid supply device 18 that supplies a grinding fluid toward the grinding wheel 17 is installed on the grinding wheel base 16.

The traverse table 11 is controlled to be fed in the Z-axis direction by a feed screw (not shown) rotated by a table drive motor 12. The wheel head 16 is controlled to advance and retreat in the X-axis direction by a feed screw (not shown) rotated by a wheel head driving motor 19.

In FIG. 1, reference numeral 20 denotes a numerical controller for controlling and managing the entire grinding apparatus.
A memory 25 storing an NC program, an input device 22
And first interface 24 connected to output device 23
And a second interface 26 connected to the table drive motor 12 and the grindstone drive motor 19 via drive circuits 28 and 27, and a third interface 29 connected to the sequence controller 30.

In the memory 25, as shown in FIG.
In addition to the G code (G00, G01...) Of the C program, in the present invention, the M code of the grinding wheel head return valid code M41 and the grinding wheel head return invalid code M42 are stored.

Further, the sequence controller 30 corresponds to FIG.
As shown by, it is turned on by the setting of the wheel head return valid code M41, and turned on by the setting of the wheel head return invalid code M42.
A sequence circuit in which a first contact point 31 to be flipped, a second contact point 32 to be closed by a failure signal E when a predetermined abnormality occurs, and a relay 33 for instructing start of returning to a grinding wheel head are arranged in series. It is. The predetermined abnormality is, for example, a stop of the rotation of the spindle (work W), a stop or overload of the grindstone 17, a stop of the supply of the grinding fluid during the processing of the work, or the like.

With the above configuration, when a signal is output to the sequence controller 30 by the grinding wheel head return valid code M41 during execution of the NC program in the memory 25 of the numerical controller 20, the first contact 31 of the sequence circuit is turned on. Turn ON. Thereafter, when a predetermined abnormality occurs,
Since the abnormal signal E is input to the sequence controller 30 and the second contact of the sequence circuit is closed, the relay 3
3 outputs a start command signal for returning the grindstone head.

The wheel head returning start command signal output from the sequence controller 30 is input to the numerical controller 20, and the wheel head returning program stored in the memory 25 of the numerical controller 20 is executed. 20
Drives the grindstone drive motor 19 via the drive circuit 27 to return the grindstone head 16 to its original position.

During the execution of the NC program, the sequence controller 30 receives
Is output to the first contact 31 of the sequence circuit.
Turns off. Thereafter, when a predetermined abnormality occurs, the abnormality signal E is input to the sequence controller 30 and the second contact 32 of the sequence circuit is closed. However, since the first contact 31 is OFF, the relay 33 is activated. Therefore, the start command signal for returning the grindstone head is not output.

A grinding cycle by the apparatus according to the present invention for performing the above-described control operation will be described with reference to the flowchart of FIG. At the start, the traverse table indexing 40 is performed to position the workpiece W supported by the headstock 14 and the tailstock 15 at a predetermined machining position. In the grinding wheel head 16, the grinding fluid is discharged 41 from the grinding fluid supply device 18. In addition, the headstock 14
Then, the spindle is started 42.

After the start of the spindle 42, a signal is output to the sequence controller 30 by the wheel head return valid code M41, and the first contact 31 of the sequence circuit is turned on. Then, the grinding wheel head rapid advance 43, grinding of the workpiece W 4
4. The operation of the wheel head retreat 45 is performed. When an abnormality such as the rotation stop of the spindle (workpiece W), the rotation stop or overload of the grindstone 17, and the stop of the supply of the grinding fluid occurs during the grinding 44, the operation is performed. Since the abnormal signal E is input to the sequence controller 30 and the second contact 32 of the sequence circuit is closed, a start command signal for returning the grindstone head is output by the relay 33, and the start command signal for returning the grindstone head is sent to the numerical controller 20. The grindstone return program stored in the memory 25 of the numerical controller 20 is executed, and the numerical controller 20 drives the grindstone drive motor 19 via the drive circuit 27,
Return the wheel head 16 to its original position.

When no abnormality occurs, the wheel head is retracted 4
After 5, a signal is output to the sequence controller 30 by the grinding wheel head return invalid code M42, and the traverse table indexing 46 is performed. The first contact 31 of the sequence circuit is turned off by the wheel head returning invalid code M42 signal output to the sequence controller 30. Thereafter, an abnormality occurs, and the abnormality signal E is input to the sequence controller 30 and the second contact 3
2 is closed, but since the first contact point 31 is OFF, the relay 33 is not operated and the start command signal for returning the grindstone head is not output.

After the traverse table indexing 46, a signal is again output to the sequence controller 30 by the grinding wheel head return valid code M41, and the first contact 31 of the sequence circuit is turned on. Then, the grindstone correction 47 is performed by moving the grindstone table 16 forward. At this time, when an abnormality such as a stop of the rotation of the grindstone 17 or a stop of the supply of the grinding fluid occurs, the abnormality signal E is sent to the sequence controller 30 as described above.
And the second contact 32 of the sequence circuit is closed, so that a start command signal for returning the grinding wheel head is output by the relay 33.
0, the wheel head returning program stored in the memory 25 of the numerical controller 20 is executed, and the numerical controller 20 sends the wheel head driving motor 19 via the drive circuit 27.
To return the grindstone head 16 to the original position.

If no abnormality occurs, a signal is output to the sequence controller 30 again by the wheel restoring invalid code M42 after the grinding wheel correction 47, and thereafter, the operation of the grinding fluid stop 48 and the traverse table return 49 is performed, and the grinding cycle is performed. To end. The first contact 31 of the sequence circuit is turned off by the wheel head returning invalid code M42 signal output to the sequence controller 30. In this case, since the grindstone head 16 is returned to its original position after the grindstone correction 47, it is not necessary to output a start command signal for returning the grindstone head, and the grindstone head return activation is invalidated.

[0023]

As described above, according to the present invention, it is possible to set whether the grinding wheel head return is enabled or disabled in the NC program. Easy. This makes it possible to standardize the sequence circuit and set the validity / invalidity of the grindstone head return by the NC program and execute the grindstone head return, thereby increasing the versatility.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a grinding device and a control unit thereof according to the present invention.

FIG. 2 is a diagram showing a memory and a sequence controller of the numerical controller according to the present invention;

FIG. 3 is a flowchart of a grinding cycle of the grinding device according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 traverse table 14 headstock 15 tailstock 16 grindstone 17 grindstone 18 grinding fluid supply device 20 numerical control device 30 sequence controller 31 first contact 32 second contact 33 relay for instructing start of grindstone head M41 M42 Wheelhead return invalid code

Continued on the front page (72) Inventor Kenji Matsuba 1-1-1 Asahi-cho, Kariya-shi, Aichi Pref.

Claims (3)

[Claims] 1. A grinding apparatus having a grindstone head for processing a workpiece and activating said grindstone head return when an ON / OFF state of each contact of a sequence circuit satisfies a specific condition. Setting means for setting whether the state of the apparatus is in a state in which the activation of the wheel head return is valid or in an invalid state, and the state of the current grinding device is in a state in which the activation of the wheel head return is valid by the setting means If it has been set, when each of the contacts meet the specific condition, start the wheel head return, the current state of the grinding device is set by the setting means to a state in which the start of the wheel head return is invalid. And a sequence controller that does not activate the wheel head return even if each of the contacts satisfies the specific condition. 2. A grinding apparatus, comprising: a grinding wheel base for processing a workpiece, wherein the on / off state of each contact of a sequence circuit activates the grinding wheel base return when certain conditions are satisfied. Setting means for setting whether the state of the apparatus is in a state in which the activation of the wheel head return is valid or in an invalid state, and the state of the current grinding device is in a state in which the activation of the wheel head return is valid by the setting means. It turns on when it is set, and at this time, when each of the contacts meets the specific condition, the grindstone head return is started, and the setting unit sets the current state of the grinding device to a state in which the start of the grindstone head return is invalid. A sequence controller having a contact that turns off the wheel when the contact satisfies the specific condition and does not activate the wheel head return when the contact satisfies the specific condition. Place. 3. The NC program according to claim 1, wherein the setting means for setting whether the current state of the grinding apparatus is in a state in which the activation of the grinding wheel head return is valid or invalid is set in an NC program. And the grinding device according to 2.