JP2010188500A - Method for confirming workpiece mounted condition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for confirming workpiece mounted condition which can determine, in a simple and reliable manner, whether the mounted condition of a workpiece having a curved surface is good or bad. <P>SOLUTION: An ultrasonic oscillator 10 is disposed on a base 1. Vibration is applied to a tool 2 in such a state as to simulate a status in which a workpiece W is not properly mounted. Vibration which propagates through the inside of the tool 2 is received by the ultrasonic oscillator 10 to store an oscillatory waveform NG in such a state that the workpiece W is absent. Vibration is applied to the tool 2 in such a state that the workpiece W is properly mounted. Vibration which propagates through the inside of the tool 2 and the inside of the workpiece W is received by the ultrasonic oscillator 10 to store an oscillatory waveform G in such a state that the workpiece W is present. At a stage before working, whether the waveform of vibration which propagates through the inside of the tool 2 and the inside of the workpiece W and is received by the ultrasonic oscillator 10 is similar to the oscillatory waveform NG in such a state that the workpiece W is absent, or the oscillatory waveform G in such a state that the workpiece W is present, is determined by a method comprising applying vibration to the tool 2 and comparing waveform features, whereby the mounted condition of the workpiece W is confirmed. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a work attachment state confirmation method used for confirming whether or not a work is correctly attached to a work attachment part of a machine tool.

Conventionally, as means for confirming the mounting state of the workpiece as described above, for example, there are those disclosed in Patent Documents 1 and 2.
The clamp / unclamp confirmation device disclosed in Patent Document 1 includes a passage opening that supplies pressure fluid to an airtight chamber formed in a jig, and a plunger that is provided in the airtight chamber and slides when pressed against a workpiece. In this clamp / unclamp confirmation device, the workpiece clamping state is confirmed by detecting the pressure change when the plunger pressed by the workpiece blocks the passage opening in the workpiece clamping state. Like to do.

  On the other hand, the workpiece seating detection device disclosed in Patent Document 2 includes a dog that moves in contact with the workpiece and a proximity sensor. In this workpiece seating detection device, the proximity sensor detects the movement of the dog. , I try to check the seating of the work.

Japanese Patent Laid-Open No. 6-15549 JP 2008-62350 A

  However, in the above-described clamp / unclamp confirmation device, the portion for confirming the clamp / unclamp has a structure in which a plunger is slidably provided in an airtight chamber having a passage opening. Although it is suitable for checking the clamp, it is difficult to apply to small workpieces. Moreover, it is necessary to make the direction which presses a workpiece | work and the sliding direction of the plunger pressed by this correspond, and there exists a problem that it is difficult to apply also to the workpiece | work which has a curved surface.

On the other hand, in the workpiece seating detection device, the movement of the dog moving in contact with the workpiece is detected by the proximity sensor, that is, the seating of the workpiece is detected by the electric means, so it is detected compared to the mechanical means. There is a problem that it cannot be said that the accuracy is high, and it has been a conventional problem to solve these problems.
The present invention has been made by paying attention to the above-described conventional problems, and is capable of easily and reliably recognizing whether or not a small workpiece or a workpiece having a curved surface is attached properly. The purpose is to provide.

  In order to achieve the above-described object, the invention according to claim 1 of the present invention is a method for confirming the attachment state of a workpiece when the workpiece is attached to the workpiece attachment portion of a machine tool. The vibration is applied to the workpiece mounting portion in a state imitating the state where the workpiece is not mounted or the workpiece is not correctly mounted, and at this time, the vibration propagating through the workpiece mounting portion is transmitted to the vibrator. And receiving a vibration waveform without a workpiece, and applying vibration to the workpiece mounting portion or the workpiece in a state where the workpiece is normally mounted, and at this time, vibration propagating through the workpiece mounting portion and the workpiece is transmitted. A vibration waveform with a workpiece received by the vibrator is stored, and the workpiece mounting is performed at a stage before the workpiece is actually mounted and processed at the workpiece mounting portion. The vibration waveform propagating through the workpiece mounting portion and the workpiece received by the vibrator at this time is similar to any of the workpiece-less vibration waveform and the workpiece-present vibration waveform. Is determined by a method of comparing waveform characteristics such as pattern matching and the like, and the structure of confirming the attachment state of the workpiece with respect to the workpiece attachment portion is characterized. As a means for solving the conventional problems.

In the workpiece attachment state confirmation method according to claim 2 of the present invention, the workpiece clamping force against the workpiece attachment portion is recognized by analyzing the propagating vibration waveform.
Furthermore, in the work attachment state confirmation method according to claim 3 of the present invention, the vibrator is an ultrasonic vibrator, and the work attachment portion is vibrated by transmission of the ultrasonic vibrator.

Furthermore, in the work attachment state confirmation method according to claim 4 of the present invention, a vibration is directly applied to the work and the vibration is propagated to the work attachment part.
In the workpiece attachment state checking method according to the present invention, the workpiece attachment portion comprises a machine tool side attachment means such as a machine tool base, a bed or a face plate, and a jig fixed to the machine tool side attachment means, and vibrates. The child is disposed on either the machine tool side mounting means or the jig.

In order to improve the sound wave propagation between the machine tool side mounting means and the jig of the workpiece mounting part, it is desirable to bring them into close contact with each other via a coupling material. If a liquid is used, a coupling material is not particularly required.
In the workpiece attachment state confirmation method according to the present invention, first, for example, a workpiece such as rubber is interposed between the workpiece and a clamp claw for fastening and fixing the workpiece, so that the workpiece is attached to the workpiece attachment portion. It creates a state that mimics the situation where it is not installed correctly.

Subsequently, the vibrator is actuated (or hit with a tool or the like) to give vibration to the workpiece mounting portion in this state, and vibration propagating through the workpiece mounting portion is received by the vibrator, and the vibration waveform (Signal waveform with time on the horizontal axis and amplitude on the vertical axis) is stored as a vibration waveform without a workpiece.
Next, in the same manner as described above, a vibration is applied to the work mounting portion or the work in a state where the work is normally mounted, and the vibration propagating through the work mounting portion is received by the vibrator, and the vibration waveform is obtained. Memorize vibration waveform with workpiece.

When the workpiece is properly mounted on this workpiece mounting section, vibration propagates not only inside the workpiece mounting section but also inside the workpiece. Therefore, the vibration waveform with the workpiece and the vibration will be affected by the difference in propagation time. The difference from the vibration waveform without work that propagates only inside becomes remarkable.
Therefore, when performing actual machining, after attaching the workpiece to the workpiece mounting portion with the clamp claw, the vibrator is operated (or struck with a jig such as a vibration hammer, or a blade such as a cutting blade or a grinding blade) The vibration waveform before machining that propagates through the workpiece mounting part and the workpiece received by the vibrator at this time is applied to the workpiece mounting part or workpiece. Match both sides of the waveform.

If it is determined whether the vibration waveform before processing is similar to the vibration waveform without workpiece or the vibration waveform with workpiece, even if it is a small workpiece or a workpiece having a curved surface, It will be possible to easily and reliably check the quality of the mounting state.
At this time, since the propagation of vibration changes depending on how the workpiece and the clamping claw hit (clamping force), if the propagation time and amplitude of the propagating vibration waveform are compared and analyzed, the tightening force in the floating state is It will be possible to identify clamp claws that are not sufficient.

  Also, when the vibrator is arranged on the machine tool side attachment means of the work attachment part, for example, the base of the machine tool, wiring and piping are performed as compared with the case where the vibrator is arranged on the jig of the work attachment part. Since it is no longer necessary, the structure becomes simple and the jig can be easily replaced.

In the work attachment state confirmation method according to the present invention, since it has the above-described configuration, it is possible to easily and reliably determine the quality of the attachment state of a small work or a work having a curved surface. Brought about.
Further, in the work attachment state confirmation method according to the present invention, by comparing and analyzing the propagation time and amplitude of the propagating vibration waveform, it is possible to recognize not only the quality of the work attachment state but also the degree of tightening of the work. It is possible to obtain a very excellent effect that the clamping force can be corrected appropriately.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a mounting state check point schematically showing a work mounting state checking method according to an embodiment of the present invention. The vibration waveform graph (a) without a workpiece, the vibration waveform graph (b) with a workpiece, and the vibration with insufficient tightening force showing signal waveforms when ultrasonic waves are emitted from the ultrasonic vibrator when checking the mounting state of the workpiece in FIG. It is a waveform graph (c).

Hereinafter, a work attachment state confirmation method according to the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of a method for confirming the mounting state of a workpiece according to the present invention.
As shown in FIG. 1, the work attachment portion of the machine tool used in this embodiment includes a base (machine tool side attachment means) 1 and a jig 2 disposed on the base 1.
The jig 2 includes a plate 3 fixed on the base 1, pedestals 4 and 5 on which the workpiece W having a curved surface disposed on the plate 3 is placed, and a clamp mechanism 6 disposed on the plate 3. 7, and these clamp mechanisms 6 and 7 operate the respective clamp claws 8 and 9 with fluid pressure such as hydraulic pressure, and fix the workpiece W by sandwiching the workpiece W together with the bases 4 and 5. It is like that.

In this case, the ultrasonic vibrator 10 is disposed in the base 1 of the work attachment portion, and the ultrasonic vibrator 10 outputs the received vibration waveform to the monitor 11. Yes.
When processing the workpiece W with a machine tool, first, between the workpiece W and the bases 4 and 5 of the jig 2 or between the workpiece W and the clamp claws 8 and 9 of the clamp mechanisms 6 and 7, By interposing rubbers 12 indicated by phantom lines, which are materials that block vibration propagation, a state imitating a situation in which the workpiece W is not correctly attached to the jig 2 is created.

  Subsequently, the jig 2 in this state is actuated by activating the ultrasonic transducer 10 to propagate through the bases 4 and 5 and the clamp mechanisms 6 and 7 of the jig 2 in FIG. The vibration indicated by the arrow of the line is received by the ultrasonic vibrator 10, and as shown in FIG. 2A, this vibration waveform (signal waveform with the horizontal axis as time and the vertical axis as amplitude) is vibration without a workpiece. The waveform NG is output (stored) to the monitor 11.

Next, the ultrasonic transducer 10 is operated in the same manner as described above to apply vibration to the jig 2 in a state where the workpiece W is normally attached, and the bases 4 and 5 of the jig 2 and the clamp mechanisms 6 and 7 are applied. 2 is received by the ultrasonic transducer 10, and this vibration waveform is output (stored) to the monitor 11 as a vibration waveform G with a workpiece, as shown in FIG. 2B.
In a state where the workpiece W is normally attached to the jig 2, the vibration is not limited to the inside of the bases 4 and 5 and the clamp mechanisms 6 and 7 of the jig 2 as indicated by the solid line arrows in FIG. Since it propagates to the inside of the workpiece W, the difference between the vibration waveform G with the workpiece and the vibration waveform NG without the workpiece in which the vibration propagates only inside the jig 2 appears remarkably by the difference in propagation time.

  Therefore, when actual machining is performed, the clamp claws 8 and 9 of the clamp mechanisms 6 and 7 are operated to fix the workpiece W to the jig 2, and then the ultrasonic vibrator 10 is operated to operate the jig 2. The vibration waveform before processing that propagates in the jig 2 and the workpiece W received by the ultrasonic vibrator 10 at this time is expressed as both the workpiece-less vibration waveform NG and the workpiece-containing vibration waveform G. Match.

If it is determined whether the vibration waveform before processing is similar to the vibration waveform NG without workpiece or the vibration waveform G with workpiece, even if the workpiece W has a curved surface as in this embodiment. Thus, it is possible to easily and surely confirm the quality of the mounting state with respect to the jig 2.
At this time, the propagation of vibration changes depending on how the workpiece W and the clamp claws 8 and 9 are brought into contact (tightening force). For example, when the contact with the workpiece W at the base 4 and the clamp claws 8 is weak, As shown in FIG. 2C, if the propagation time and amplitude of the propagating vibration waveform NG1 are analyzed (simply compared with the vibration waveform G with a workpiece), the tightening force in the floating state Therefore, it is possible to identify the clamp claw 8 (base 4) that is not sufficient.

In this embodiment, since the ultrasonic vibrator 10 is disposed on the base 1 of the work attachment portion, wiring and piping are performed as compared with the case where the ultrasonic vibrator 10 is disposed on the jig 2 of the work attachment portion. Since it is no longer necessary, the structure becomes simple and the jig can be easily replaced.
In the above embodiment, in order to improve the sound wave propagation between the base (machine tool side mounting means) 1 and the jig 2 arranged on the base 1, both are connected via a coupling material. Although it is desirable to make the seals in close contact with each other, a coupling material is not particularly required if cutting oil or a coolant is used in the processing.

  In the above-described embodiment, the vibrator is the ultrasonic vibrator 10, and the vibration is applied to the jig 2 of the work mounting portion by the transmission of the ultrasonic vibrator 10. However, the invention is not limited to this. Instead, as another configuration, for example, a configuration in which the workpiece W is vibrated by being tapped with a tool or the like and this vibration is propagated to the jig 2 may be used. You may make it give a vibration by lightly touching the workpiece | work W (or a stationary tool).

  In addition, the structure of the attachment state confirmation method of the workpiece | work which concerns on this invention is not limited to an above-described Example.

1 Base (work mounting part)
2 Jig (work mounting part)
10 Ultrasonic vibrator G Vibration waveform with workpiece NG Vibration waveform without workpiece W Work

Claims (4)

A method for confirming the mounting state of a workpiece when the workpiece is mounted on a workpiece mounting portion of a machine tool,
Place the vibrator on the work mounting part,
A vibration is applied to the workpiece mounting portion in a state in which the workpiece is not attached or a state in which the workpiece is not correctly attached, and at this time, the vibration propagating through the workpiece attaching portion is received by the vibrator. A vibration waveform without a workpiece is stored, and vibration is applied to the workpiece attachment portion or the workpiece in a state where the workpiece is normally attached. At this time, vibrations propagating in the workpiece attachment portion and the workpiece are transmitted by the vibrator. Receive and memorize the vibration waveform with workpiece,
In the stage before the workpiece is actually attached to the workpiece attachment portion and processed, the workpiece attachment portion or the workpiece is vibrated and propagated in the workpiece attachment portion and the workpiece received by the vibrator at this time. Determining whether the vibration waveform to be similar to the vibration waveform without workpiece or the vibration waveform with workpiece is by a method of comparing the waveform characteristics, and confirming the mounting state of the workpiece with respect to the workpiece mounting portion. A method for checking the mounting state of the workpiece.   The workpiece attachment state confirmation method according to claim 1, wherein the workpiece clamping state is recognized by analyzing the propagating vibration waveform.   The work attachment state confirmation method according to claim 1, wherein the vibrator is an ultrasonic vibrator, and vibration is applied to the work attachment portion by transmission of the ultrasonic vibrator.   The work attachment state confirmation method according to claim 1 or 2, wherein vibration is directly applied to the work and the vibration is propagated to the work attachment portion.

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