JP2002370141A - Apparatus and method for detecting vibration of working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect vibration with higher precision by preventing damping of vibration and intrusion of disturbance vibration at the time of detecting vibration of a working machine. SOLUTION: Vibration is gathered by a hollow rotation shaft 12 directly contacting a grinding wheel 1 which is a member used as a vibration generation source, and this vibration is taken out from a diaphragm 18 provided at the edge of the hollow rotation shaft 12 as an electrical signal by an acoustic emission sensor 19 through a coolant. Therefore, during vibration detection by the acoustic emission sensor 19, damping of vibration and intrusion of disturbance vibration can be prevented, and degradation of vibration component can be suppressed as much as possible. Moreover, a separated specific vibration component is mainly transmitted to the acoustic emission sensor 19 by a resonance pipe 17 which is built in an axial center section of the hollow rotation shaft 12 and has a bore and length as resonates at a specific vibration frequency. Therefore, only a desired vibration component can be taken out by the acoustic emission sensor 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the detection of vibration of a processing machine having a rotating shaft, which rotates a tool or a work by the rotating shaft to relatively rotate the tool and the work to perform machining. The present invention relates to a device for accurately performing the operation.

[0002]

2. Description of the Related Art Conventionally, a vibration detection device of a processing machine has been used for the purpose of confirming contact between a workpiece and a tool in a wide range of machining such as grinding and milling. Such a vibration detecting device usually includes an AE (Acoustic E).
mission) sensors are used. The AE sensor converts mechanical energy into electric energy by utilizing the fact that a mechanical stress is applied to a voltage single crystal such as quartz, lithium niobate, barium titanate, etc. to generate dielectric polarization and generate an electric field. It is. Then, the vibration (mechanical energy) transmitted to the AE sensor is grasped as a change in voltage, and the vibration is detected. Then, the processing conditions are optimized based on the detected vibration.

FIG. 3 shows a conventional processing machine provided with the AE sensor as a vibration detecting device. The case 3 of the rotating shaft 2 that rotates the grindstone 1 is slidably supported in directions indicated by arrows A and B. Work W
Is supported at one end by a rotating shaft case 5 having a clamp device 4 using a collet or the like, and the other end is supported by a center 7 of a tailstock 6 slidable in the direction indicated by arrow C. The AE sensor 8 is attached to the case 3 of the rotating shaft of the grindstone 1, the AE sensor 9 is attached to the rotating shaft case 5 of the work W, and the AE sensor 10 is attached to the tailstock 6. Based on this, the contact between the grindstone 1 and the work W is detected.

[0004]

However, where the conventional vibration detecting device is installed, the AE sensors 8, 9, and 10 are all far from the source of vibration (the point of contact between the grindstone 1 and the work W). For this reason, in the process until the vibration is transmitted to each of the AE sensors 8, 9, and 10, the vibration components detected by each AE sensor are affected by the attenuation of the vibration to be obtained and the mixing of unnecessary disturbance vibration. Deterioration will occur. For example, in the case of the AE sensor 8, the grinding wheel press 1
1. Since vibrations are transmitted through the members of the rotating shaft 2, the bearing (not shown), and the case 3, the vibrations due to the influence of physical properties such as the natural frequency, mass, Young's modulus, and elastic modulus of these members. Inevitably, disturbance vibrations such as damping of the bearings, rotational vibrations of the bearing balls, and vibrations of the motor driving the rotary shaft 2 cannot be avoided.

Moreover, the conventional vibration detecting device converts the vibration, which has been deteriorated when transmitted to the AE sensors 8, 9 and 10, into an electric signal by the AE sensor, and further converts the electric signal into an electric filter. A method is adopted in which only the vibration component desired to be obtained is obtained by processing. However, in the case where disturbance vibration having the same frequency as the vibration to be obtained in the transmission process is mixed, it is impossible to separate only the disturbance vibration. If the level is reduced to a level at which it cannot be electrically separated, or if it is lower than the noise component, it is impossible to detect the vibration component desired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a rotary shaft, which is used to rotate a tool or a work to rotate the tool and the work relative to each other. It is another object of the present invention to prevent vibration attenuation and disturbance vibration intrusion when performing vibration detection of a processing machine that performs machining, thereby enabling more accurate vibration detection.

[0007]

According to a first aspect of the present invention, there is provided a vibration detecting apparatus for a processing machine, comprising:
A vibration detection device for a processing machine having a rotating shaft, comprising an AE sensor that uses a member directly in contact with a member serving as a vibration generation source as a vibration detection unit and extracts a vibration detected by the member as an electric signal. It is characterized by the following.

According to the present invention, a member directly in contact with a member serving as a vibration source is used as vibration detecting means, and the vibration detected by the member is taken out as an electric signal by the AE sensor. When performing vibration detection,
It is possible to avoid the attenuation of the vibration and the intrusion of the disturbance vibration, and to suppress the deterioration of the vibration component as much as possible.

According to a second aspect of the present invention, there is provided a vibration detecting device for a processing machine according to the first aspect of the present invention, wherein the member separates a specific vibration component from the vibration of the own machine. This is done only by the target structure. According to the present invention, by separating a specific vibration component in a member directly in contact with the member serving as the vibration generation source,
The separated specific vibration component is mainly transmitted to the AE sensor. Moreover, by separating the specific vibration component only by the mechanical structure of the member itself, the vibration component can be separated without being affected by the characteristics of the processing circuit and the like as in the case of electrical processing. Can be performed.

According to a third aspect of the present invention, in the vibration detecting apparatus for a processing machine according to the second aspect of the present invention, the member is configured to amplify a specific vibration component by using its own machine. This is done only by the target structure. According to the present invention, by amplifying a specific vibration component in a member directly in contact with the member serving as the vibration generation source,
The separated specific vibration component is amplified and transmitted to the AE sensor. Moreover, by amplifying the specific vibration component only by the mechanical structure of the member itself, the amplification of the vibration component is not affected by the characteristics of the processing circuit and the like as in the case of electrical processing. Can be performed.

According to a fourth aspect of the present invention, in the vibration detecting apparatus for a processing machine according to the second aspect, the member has a diameter and a length for transmitting a specific vibration frequency satisfactorily. And a solid rotating shaft whose end is a vibration transmitting portion to the AE sensor. According to the present invention, the AE sensor is transmitted with a mainly separated specific vibration component by the solid rotary shaft having a diameter and a length that transmit a specific vibration frequency well. It will be. Further, the specific vibration component can be separated only by the mechanical structure of the solid rotary shaft itself.

According to a fifth aspect of the present invention, there is provided a vibration detecting device for a processing machine, wherein the member has an inner diameter and a length which resonate at a specific vibration frequency. The resonance tube is a hollow rotary shaft having a built-in resonance tube in the axial center portion, and an end portion of the resonance tube serving as a vibration transmission unit to the AE sensor. According to the present invention, the resonance tube having the inner diameter and the length that resonates at a specific vibration frequency, which is built in the shaft core portion of the hollow rotary shaft, is used for the above-described A.
A specific vibration component that is mainly separated is amplified and transmitted to the E sensor. Further, the specific vibration component can be separated and amplified only by the mechanical structure of the hollow rotary shaft itself.

According to a sixth aspect of the present invention, there is provided a vibration detecting apparatus for a processing machine according to the fifth aspect of the present invention, further comprising a diaphragm for closing an end of the resonance tube. With this configuration, when machining using the coolant, it is possible to prevent a change in the separation / amplification characteristics of the vibration component due to the coolant entering the resonance tube.

According to a seventh aspect of the present invention, there is provided a vibration detecting apparatus for a processing machine according to any one of the fourth to sixth aspects, wherein the rotating shaft has a tool itself. Is provided. According to the present invention, by supporting a tool that constitutes a vibration source at the time of machining with a workpiece by means of a tool attached to the rotating shaft itself, vibration is detected when the AE sensor detects vibration. Of the vibration and the intrusion of disturbance vibration can be avoided, and the deterioration of the vibration component can be suppressed as much as possible.

According to an eighth aspect of the present invention, in the vibration detecting device for a processing machine according to any one of the fourth to sixth aspects, the rotating shaft is provided on the workpiece itself. Is provided. According to the present invention, by supporting a work constituting a vibration source at the time of machining with a tool by a work mounting means provided on the rotary shaft itself, vibration is detected when the AE sensor detects vibration. Of the vibration and the intrusion of disturbance vibration can be avoided, and the deterioration of the vibration component can be suppressed as much as possible.

According to a ninth aspect of the present invention, there is provided a vibration detecting method for a processing machine having a rotary shaft, the method comprising: Vibration is picked up by a solid rotary shaft having a diameter and a length that directly contacts and transmits a specific vibration frequency well, and separation of a specific vibration component is performed only by the mechanical structure of the rotary shaft itself, The separated specific vibration component is extracted as an electric signal from an end of the solid rotation shaft by an AE sensor.

According to the present invention, vibration is picked up by a solid rotating shaft directly in contact with a member serving as a vibration generating source, and the vibration picked up by the rotating shaft is converted into an electric signal by the AE sensor from an end thereof. Since it is taken out, when the AE sensor detects a vibration, attenuation of the vibration and intrusion of disturbance vibration can be avoided, and deterioration of the vibration component can be suppressed as much as possible. Also,
Since the solid rotation shaft has a diameter and a length that can transmit a specific vibration frequency well, the AE sensor is mainly transmitted with a specific vibration component that is separated. Moreover, the separation of the specific vibration component is performed only by the mechanical structure of the solid rotating shaft itself, so that the characteristics of the processing circuit and the like are not affected as in the case of the electrical processing. It becomes possible to separate such vibration components.

According to a tenth aspect of the present invention, there is provided a vibration detecting method for a processing machine having a rotating shaft, the method comprising the steps of: Vibration is picked up by a hollow rotary shaft that has a built-in resonance tube with an inner diameter and length that directly contacts and resonates at a specific vibration frequency at the specific vibration frequency, and separates a specific vibration component.
Amplification is performed only by the mechanical structure of the rotating shaft itself,
A specific vibration component separated and amplified is extracted as an electric signal from an end of the rotating shaft by an AE sensor.

According to the present invention, the vibration is picked up by the hollow rotary shaft directly in contact with the member serving as the vibration source, and the vibration picked up by the rotary shaft is extracted as an electric signal from the end by the AE sensor. Therefore, when vibration is detected by the AE sensor, it is possible to prevent the attenuation of vibration and the intrusion of disturbance vibration, and to suppress the deterioration of the vibration component as much as possible. Also,
By a resonance tube having an inner diameter and a length that resonates at a specific vibration frequency, which is built in the center of the hollow rotary shaft,
A specific vibration component separated mainly is amplified and transmitted to the AE sensor. Moreover, by separating the specific vibration component only by the mechanical structure of the hollow rotary shaft itself, as in the case of electrical processing,
Such vibration components can be separated without being affected by the characteristics of the processing circuit and the like.

[0020]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, the same parts and corresponding parts as in the prior art are denoted by the same reference numerals, and detailed description is omitted.

FIG. 1 schematically shows a sectional view of a processing machine having a vibration detecting device according to an embodiment of the present invention. The hollow shaft 12 for fixing the whetstone 1 to one end is provided with a case 13
Are rotatably supported via bearings 14 and 15. A resonance tube 17 having an inner diameter and a length that resonates at a specific vibration frequency is provided on a shaft core portion of the hollow shaft 12 through a vibration isolator 16.
Is provided. Further, the end of the resonance tube 17 is closed by the diaphragm 18 to prevent the coolant from entering the resonance tube 17 when performing processing using the coolant. And
The vibration plate 18 closing the end of the resonance tube 17 is a vibration transmission unit to the AE sensor 19. The diaphragm 18 and the AE sensor 19 are not in contact with each other, and a slight gap e is provided between the two so that a coolant used for processing can be interposed.

In FIG. 1, a portion indicated by reference numeral 20 is a pulley for driving the hollow shaft 12, and a driving force of a motor (not shown) is transmitted to the pulley 20 by a belt 21.
The AE sensor 19 may be provided at the end of the hollow shaft 12 on the side of the grindstone holder 11. Further, the clamp device, tailstock, center and the like for the work W can be the same as those in the conventional example shown in FIG.

The operation and effect obtained by the embodiment of the present invention having the above configuration are as follows. First, vibration is detected by the hollow rotary shaft 12 which is in direct contact with the grindstone 1 which is a member serving as a vibration source. Subsequently, the vibration detected by the hollow rotary shaft 12 is extracted as an electric signal by the AE sensor 19 from the diaphragm 18 provided at the end of the hollow rotary shaft 12 via the coolant. Therefore, when vibration is detected by the AE sensor 19, attenuation of vibration and intrusion of disturbance vibration can be avoided, and deterioration of vibration components can be suppressed as much as possible.

At this time, the AE sensor 19 is mainly separated from the AE sensor 19 by a resonance tube 17 having an inner diameter and a length that resonates at a specific vibration frequency and is built in the shaft center of the hollow rotary shaft 12. A vibration component is transmitted.

FIG. 2 shows a waveform of a vibration obtained by the vibration detecting device according to the embodiment of the present invention. The graph of FIG. 2A shows vibration components in all frequency ranges, and shows a waveform at the time of idling by a solid line and a waveform at the time when the grinding wheel 1 and the work W come into contact with each other by a dotted line. In the figure, the vibration appearing in the frequency band of the area A is the vibration component of the bearings 14 and 15. Further, the vibration appearing in the frequency band of the region B is a vibration component due to the rotation of the hollow shaft 12. Further, the vibration appearing in the frequency band of the region C is a higher-order wave component. Then, the vibration appearing in the frequency band of the region D is a vibration component of the natural vibration caused by the contact between the grinding wheel 1 and the work W.

On the other hand, the graph of FIG. 2 (b) shows the vibration component after the necessary vibration frequency is separated and amplified by the resonance tube 17 of the hollow shaft 12, and the waveform at the time of idling is indicated by a solid line. The waveform at the time when the grinding wheel 1 and the workpiece W come into contact with each other is shown by a dotted line. As described above, only the vibration component of the natural vibration generated by the contact between the grindstone 1 and the work W in the region D is remarkably exhibited. In addition, the separation of the specific vibration component is performed by the mechanical structure of the hollow rotary shaft 12 itself (the inner diameter and length of the hollow shaft 12 that resonate at a specific vibration frequency through the vibration isolator 16 via the vibration isolator 16). With a resonance tube 17 having a height.) Therefore, as in the related art, by performing an electrical filtering process or the like, it becomes possible to separate such vibration components without being affected by the characteristics of the processing circuit or the like, as in a method of extracting only the vibration components to be obtained. .

As described above, according to the embodiment of the present invention, when detecting vibration of a processing machine for performing machining, it is possible to avoid vibration attenuation and intrusion of disturbance vibration, and to detect vibration with higher accuracy. It becomes possible. Therefore, processing conditions can be optimized based on the detected high-precision vibration components. In addition, the detection sensitivity of necessary vibration components is greatly improved,
For example, when performing processing using a coolant, even a relatively small vibration such as a vibration component caused by a wedge effect of the coolant immediately before the grindstone 1 actually contacts the workpiece W is accurately detected. It is also possible to do. Therefore,
By optimizing the timing of changing the feed speed from the rapid feed to the low-speed grinding feed, it is also possible to reduce the processing cycle time.

Further, by closing the end of the resonance tube 17 with the diaphragm 18, a change in the separation / amplification characteristics of the vibration component due to the penetration of the coolant into the resonance tube 17 at the time of performing the processing using the coolant. Is preventing.

When no coolant is used during the processing, the diaphragm 18 does not need to be provided. In such a case, grease is applied to a slight gap between the end of the resonance tube 17 and the AE sensor 19, and the vibration picked up by the hollow rotary shaft 12 is removed from the end of the resonance tube 17 by grease. Via the AE sensor 19
And extract it as an electric signal.

Further, in a processing machine provided with the vibration detecting device according to the embodiment of the present invention, a solid shaft may be used in place of the hollow shaft 12. In this case, a solid shaft having a diameter and a length capable of transmitting a specific vibration frequency satisfactorily is used, and its end is used as a vibration transmitting unit to the AE sensor 19. In such a case, the separated specific vibration component is mainly transmitted to the AE sensor 19,
This is particularly effective when the desired vibration frequency can be extracted without amplification.

That is, in the embodiment of the present invention, the member directly in contact with the grindstone 1, which is a member serving as a vibration generating source, is not limited to the hollow rotary shaft 12, and for example, the vibration is generated by mechanical vibration. Any means can be used as long as the vibration transmitting means matches an integral multiple of the resonance point (resonance frequency) of the desired vibration with its own natural frequency. If such a condition is satisfied, for example, vibration can be detected by an AE sensor from a clamp device that grips a work.

Further, the invention according to the embodiment of the present invention has a rotating shaft, and the tool or the work is driven to rotate by the rotating shaft to relatively rotate the tool and the work, thereby performing machining. The present invention can be generally applied, and for example, can also be used for a rotating shaft of a milling machine.

[0033]

According to the present invention, the following effects are obtained. First, according to the vibration detecting apparatus for a processing machine according to claim 1 of the present invention, the apparatus has a rotating shaft, and the tool and the work are driven to rotate by the rotating shaft, thereby relatively rotating the tool and the work, and When performing vibration detection of a processing machine that performs vibration, it is possible to avoid vibration attenuation and intrusion of disturbance vibration, and to perform vibration detection with higher precision.

According to the vibration detecting device for a processing machine according to the second aspect of the present invention, a specific vibration component mainly separated is transmitted to the AE sensor to detect vibration with higher accuracy. Becomes possible. Moreover, by separating the specific vibration component only by the mechanical structure of the member itself, the vibration component can be separated without being affected by the characteristics of the processing circuit and the like as in the case of electrical processing. Can be performed, and highly accurate vibration detection can be stably performed.

Further, according to the vibration detecting device for a processing machine according to the third aspect of the present invention, a specific vibration component mainly separated is amplified and transmitted to the AE sensor, and the vibration is relatively small. However, more accurate vibration detection can be performed. Moreover, by separating the specific vibration component only by the mechanical structure of the member itself, the vibration component can be separated without being affected by the characteristics of the processing circuit and the like as in the case of electrical processing. Can be performed. Then, it is possible to stably perform highly accurate vibration detection.

According to the vibration detecting device for a processing machine according to the fourth aspect of the present invention, a specific vibration component which is mainly separated is transmitted to the AE sensor, thereby detecting vibration with higher accuracy. Becomes possible. Moreover, by separating the specific vibration component only by the mechanical structure of the member itself, the vibration component can be separated without being affected by the characteristics of the processing circuit and the like as in the case of electrical processing. Can be performed. Then, it is possible to stably perform highly accurate vibration detection.

According to the vibration detecting device for a processing machine according to the fifth aspect of the present invention, a specific vibration component mainly separated is amplified and transmitted to the AE sensor, and the vibration is relatively small. However, more accurate vibration detection can be performed. Moreover, by separating the specific vibration component only by the mechanical structure of the member itself, the vibration component can be separated without being affected by the characteristics of the processing circuit and the like as in the case of electrical processing. Can be performed. Then, it is possible to stably perform highly accurate vibration detection.

According to the vibration detecting device for a processing machine according to the sixth aspect of the present invention, even when performing processing using a coolant, the vibration component is separated by the coolant entering the resonance tube. -It is possible to prevent a change in amplification characteristics and to stably perform high-precision vibration detection.

Further, according to the vibration detecting device for a processing machine according to claim 7 of the present invention, when vibration is detected by the AE sensor, a member having a tool mounting means serving as a vibration generating source is provided. By picking up the vibration, it is possible to avoid the attenuation of the vibration and the intrusion of the disturbance vibration, and to suppress the deterioration of the vibration component as much as possible. Therefore, highly accurate vibration detection can be performed.

Further, according to the vibration detecting device for a processing machine according to claim 8 of the present invention, when vibration is detected by the AE sensor, a member provided with means for attaching a work which is a member serving as a vibration generating source is provided. By picking up the vibration, it is possible to avoid the attenuation of the vibration and the intrusion of the disturbance vibration, and to suppress the deterioration of the vibration component as much as possible. Therefore, highly accurate vibration detection can be performed.

According to a vibration detecting method for a processing machine according to a ninth aspect of the present invention, a rotary shaft is provided, and a tool or a work is rotated by the rotary shaft to relatively rotate the tool and the work. When detecting vibration of a machining machine that performs machining, avoid vibration attenuation and intrusion of disturbance vibration,
It is possible to detect vibration with higher accuracy. Further, according to the vibration detection method for a processing machine according to claim 10 of the present invention, the same effect as the invention according to claim 9 of the present invention is obtained.
It can also be obtained when detecting relatively small vibrations.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a cross section of a processing machine including a vibration detection device according to an embodiment of the present invention.

FIGS. 2A and 2B are graphs showing waveforms of vibrations obtained by the vibration detection device of the processing machine shown in FIG. 1, in which FIG. 2A separates and amplifies vibration components in all frequency ranges, and FIG. This shows the vibration component after the vibration.

FIG. 3 is a schematic view of a conventional processing machine including a vibration detection device.

[Explanation of symbols]

 1 Grinding Stone 11 Grinding Stone Holder 12 Hollow Shaft 13 Case 14, 15 Bearing 16 Vibration Isolator 17 Resonance Tube 18 Vibration Plate 19 AE Sensor 20 Drive Pulley 21 Belt W Work

Claims (10)

[Claims] 1. A vibration detection device for a processing machine having a rotation axis, wherein a member directly in contact with a member serving as a vibration generation source is used as vibration detection means, and vibration detected by the member is extracted as an electric signal. A vibration detection device for a processing machine, comprising an AE sensor. 2. The method according to claim 1, wherein the member separates a specific vibration component.
2. The vibration detecting device for a processing machine according to claim 1, wherein the vibration is detected only by its own mechanical structure. 3. The method according to claim 1, wherein the member amplifies a specific vibration component.
3. The vibration detecting device for a processing machine according to claim 2, wherein the vibration is detected only by its own mechanical structure. 4. The solid rotating shaft, wherein the member has a diameter and a length for transmitting a specific vibration frequency well, and has an end portion serving as a vibration transmitting portion to the AE sensor. The vibration detecting device for a processing machine according to claim 2, wherein: 5. The member, wherein a resonance tube having an inner diameter and a length that resonates at a specific vibration frequency is built in an axial center portion, and an end of the resonance tube serves as a vibration transmission unit to the AE sensor.
The vibration detecting device for a processing machine according to claim 3, wherein the vibration detecting device is a hollow rotary shaft. 6. The vibration detecting device for a processing machine according to claim 5, further comprising a diaphragm closing an end of said resonance tube. 7. The vibration detecting device for a processing machine according to claim 4, wherein said rotating shaft has a tool attaching means on itself. 8. The vibration detecting device for a processing machine according to claim 4, wherein said rotating shaft has a means for attaching a work to itself. 9. A method for detecting vibration of a processing machine having a rotating shaft, comprising: a solid rotation having a diameter and a length that directly contacts a member serving as a vibration generating source and transmits a specific vibration frequency satisfactorily. The vibration is picked up by the shaft, the specific vibration component is separated only by the mechanical structure of the rotary shaft itself, and the separated specific vibration component is separated from the end of the rotary shaft by A
A vibration detection method for a processing machine, wherein the vibration is detected as an electric signal by an E sensor. 10. A vibration detecting method for a processing machine having a rotating shaft, comprising: a resonance tube having an inner diameter and a length that directly contacts a member serving as a vibration generating source and resonates at a specific vibration frequency; Vibration is picked up by a hollow rotary shaft incorporated in the rotary shaft, separation and amplification of a specific vibration component is performed only by the mechanical structure of the rotary shaft itself, and the separated and amplified specific vibration component is transferred to the end of the rotary shaft. A method for detecting vibrations of a processing machine, wherein the vibrations are extracted as electrical signals from a section by an AE sensor.