JPH05104407A - Non-contact measuring method for material to be machined and device thereof - Google Patents

Abstract

PURPOSE:To enable in-process measurement during the working operation by installing an ultrasonic sensor in a tool or in a material to be machined, outputting an ultrasonic wave in a condition that a liquid column is created relative to the other reflecting surface, and measuring a dimension by means of measurement of a reflecting time in measurement for a machine tool. CONSTITUTION:Coolant 25 is introduced into a nozzle 2 from a tank 24 through a coolant inlet port 22 by means of a pump 23, and a liquid column 20 is formed relative to a reflecting surface 41 (obverse) of a material 40 to be machined and the coolant inlet port. In this condition, a distance between the transmitting surface of an ultrasonic sensor 10 and the reflecting surface 41 (obverse) of the material 40 to be ground is maintained in a prescribed value, for example, approximately 5mm, and an oil feeding quantity is kept properly, and an interval X to the liquid column 20 is maintained in a constant condition. In this condition, an ultrasonic wave is transmitted by the ultrasonic sensor 10, and the reflection is received by a transmitter- receiver 11, and it is processed by a control device 12, so that a reflecting time can be measured. By repeating this transmission/reception at a time interval, a grinding margin can be calculated based on repeatedly received data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring a work body of various machine tools, and particularly to a machining allowance of the work body, a size of the work body,
Alternatively, the present invention relates to a method and an apparatus for measuring the wear allowance of a grinding wheel during a working operation.

[0002]

2. Description of the Related Art Conventionally, a contact type measuring method, a laser measuring method, and an ultrasonic measuring method have been used to measure the grinding allowance of a workpiece to be ground during grinding in a grinder (referred to as in-process measurement). Has been taken. In the first contact-type measuring method, the probe such as a dial gauge or a differential transformer is brought into contact with a moving object to be measured, so that the unevenness of the surface causes the probe to vibrate, and the vibration causes measurement noise. .. In a grinding machine, a measurement accuracy of about 1 μm is usually required. Therefore, if the measurement noise is equal to or higher than the required accuracy, it cannot be measured by this contact type measurement method. That is, the non-grinding object is removed from the grinder and moved to a required surface plate for measurement. In the second laser measuring method, the wavelength of the laser light is 1064 nm even in the YAG laser, and is several hundred nm in the other lasers such as the helium-neon laser, the argon laser, and the accuracy. From the point of view, it is the most excellent enough. However, it is most likely to be affected by grinding fluid, grinding dust, wind, etc., and lacks stability. In addition, the price of the measuring device is expensive, and the maintenance also requires a suitable technique. In the third ultrasonic measurement method, the frequency range that is normally used is about several hundred kHz, which is most preferable.

[0003]

However, even in the ultrasonic measuring method, as in the laser measuring method, the ultrasonic measuring method has a drawback that it is easily influenced by the working oil, the processing dust, the wind, etc. flowing on the surface of the workpiece. Was there.

In view of the drawbacks of the prior art, the present invention has been made.
Depending on the ultrasonic measurement method, the machining allowance of the work piece, the size of the work piece,
Another object of the present invention is to provide a method and an apparatus capable of measuring the wear allowance of a grinding wheel in-process during processing work.

[0005]

According to the present invention, an ultrasonic wave is output from the ultrasonic sensor mounted on the machining tool side and a reflecting surface on the workpiece side in a state where a liquid column is generated. Then
It is characterized in that the machining allowance or the dimension of the work piece is measured by utilizing the reflection time of the output wave. Further, according to the present invention, an ultrasonic wave is output from the sensor in a state where a liquid column is generated between the ultrasonic sensor attached to the work piece side and the reflecting surface on the working tool side, and the reflection time of the output wave Is used to measure the machining allowance or the size of the work piece. In addition, preferably, the frequency of the ultrasonic waves is 1 MHz or more. It is preferable that the liquid that forms the liquid column is the same type of liquid as the processing oil. The processing tool is a cutting tool or a grinding wheel.

Further, the present invention comprises an ultrasonic sensor mounted on the side of the machining tool so as to face the reflecting surface on the side of the workpiece, and a liquid supply means arranged so as to surround the outer circumference of the sensor. It is characterized in that a liquid column can be generated between the ultrasonic wave output part of the sensor and the reflection surface by using the supplied liquid. Alternatively, the present invention comprises an ultrasonic sensor mounted on the side of the workpiece, facing the reflection surface on the side of the processing tool, and a liquid supply means arranged so as to surround the outer periphery of the sensor,
It is characterized in that a liquid column can be generated between the ultrasonic wave output part of the sensor and the reflection surface by using the liquid supplied from the supply means.

Further, according to the present invention, an ultrasonic wave is output from the sensor in the state where a liquid column is generated between the ultrasonic sensor mounted on the apparatus main body side and the grinding surface of the grinding wheel, and the output wave The feature is that the wear allowance of the grinding wheel is measured using the reflection time.

[0008]

According to such a technical means, the ultrasonic wave is output from the sensor in the state where the liquid column is generated between the ultrasonic sensor attached to the machining tool side and the surface on the side of the workpiece. Since it is configured to measure the machining allowance using the reflection time of the wave, the ultrasonic wave repeatedly transmitted at a constant time interval via the liquid column generated between the ultrasonic sensor and the surface of the workpiece. The in-process measurement of the machining allowance of the work piece can be performed by measuring the time difference between the output wave of the work piece and the reflected wave from the surface of the work piece. At the same time, the reflected wave from the bottom surface of the work is received at the same time as the reflected wave from the work surface, and the time with the output wave is measured, whereby the size of the work can be obtained. Moreover, since only the liquid column exists between the ultrasonic sensor and the surface of the work piece, the measurement can be performed without being affected by the working oil agent, the processing waste, or the wind flowing on the surface of the work piece. .. Moreover, since only the liquid column exists between the ultrasonic sensor and the surface of the workpiece, there is no measurement noise due to physical contact as in the contact type measurement method, and the measurement can be performed with desired accuracy.

Since the frequency of ultrasonic waves is set to 1 MHz or higher, the sound velocity when transmitting in the conventional air (about 330 m / s) and the sound velocity when transmitting in the liquid column according to the present invention (about 1500 m). The measurement accuracy based on the difference of / s) can be maintained at the same level or higher. This means that when measuring the plate thickness of a work piece, the sound velocity in steel is about 580.
It is effective because it is 0 m / s. That is, in the present invention, it is not directly related to the frequency of the ultrasonic wave for measuring the time between the output wave and the reflected wave, but in order to maintain the accuracy,
A high frequency is desirable. Fortunately, it is steadily growing against the backdrop of advances in materials and parts, and ultrasonic sensors (ultrasonic wave generation elements) of several hundred MHz are also practical. By using a liquid that produces the liquid column as a liquid of the same type as the processing oil agent, in-process measurement can be performed without disturbing the processing operation by the liquid, and the operation after the processing operation of the workpiece, for example, Oil removal work and surface treatment can be performed without changing the conventional treatment work.

Further, even if an ultrasonic sensor is attached to the work body side and an ultrasonic wave is output from the sensor in a state where a liquid column is generated between the ultrasonic wave sensor and the reflecting surface on the machining tool side, the same action as described above can be obtained. Be done. That is, the output wave emitted from the ultrasonic sensor arranged on the bottom surface of the work piece is reflected from the bottom surface and the grinding surface of the work piece and received by the sensor, and by measuring the reflection time of the output wave, The machining allowance of the machined body and the size of the machined body can be obtained.

Further, according to the present invention, there is provided an ultrasonic sensor mounted on the machining tool side so as to face the reflection surface on the side of the workpiece, and a liquid supply means arranged so as to surround the outer periphery of the sensor, By using the supply liquid from the means, since it is possible to generate a liquid column between the ultrasonic output portion of the sensor and the reflection surface, by measuring the reflection time of the output wave transmitted from the sensor, It is possible to provide a non-contact measuring device capable of measuring the machining allowance of a workpiece and the dimensions of the workpiece.
Further, even if it is provided with an ultrasonic sensor which is attached to the work body side so as to face the reflecting surface of the machining tool side and a liquid supply means which is arranged so as to surround the outer circumference of the sensor, the operation of the measuring method will be described. As described above, it is possible to provide a non-contact measuring device that has the same operation as the above-described structure and that can measure the machining allowance of the work piece and the dimensions of the work piece.

Further, according to the present invention, the ultrasonic wave is output from the sensor in the state where a liquid column is generated between the ultrasonic sensor attached to the apparatus main body side and the grinding surface of the grindstone, and the ultrasonic wave is output from the ultrasonic wave. Since it is configured to be able to measure the wear allowance of the grinding wheel using the reflection time, ultrasonic waves reciprocating between the sensor and the polishing surface of the grinding wheel is performed only through the liquid column, the surface of the grinding wheel It is possible to provide a method for measuring a grinding wheel wear margin that is not affected by irregularly flowing grinding fluid, grinding dust, and the like.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described in detail below as an example with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described in this embodiment are not intended to limit the scope of the present invention thereto, but are merely illustrative examples. Not too much.

FIG. 2 is a front view showing the structure of a surface grinder used in an embodiment of the present invention, in which reference numeral 40 denotes an object to be ground which is fixed to a bed 50 which is automatically and manually fed in the horizontal direction. The body 40 faces the grindstone head 31. The grinding head 31
Has a rotating grindstone 30 and is capable of automatic and manual cutting feed in the vertical direction. A nozzle 21 that houses the ultrasonic sensor 10 is installed on the side wall of the grindstone 31, and the ultrasonic sensor 10 is provided above the nozzle 21.
An electric wire 13 for transmitting a signal for transmitting / receiving and a inlet 22 for a grinding fluid 25 introduced to generate a liquid column 20 are provided in the nozzle 21.

FIG. 1 is a schematic front view showing the structure of an ultrasonic sensor 10 according to an embodiment of the present invention.
Is connected to the transmission / reception device 11 and the control device 12 via an electric wire 13. The controller 12 calculates the time between the output wave and the received wave from the transmitter / receiver 11, measures and displays the grinding allowance and the plate thickness 43 of the object to be ground 40, and also performs the surface grinding to perform automatic sizing according to the set value. It is configured to control the board. A grinding fluid 25 stored in a tank 24 is introduced into the nozzle 21 by a pump 23 through a grinding fluid inlet 22. Therefore, the liquid column 20 is generated in the nozzle 21 by the grinding fluid 25. The surface 4 of the object to be ground 40 facing the transmitting surface of the ultrasonic sensor 10.
By maintaining the distance X between the liquid column 1 and 1 to be approximately 5 mm, and by appropriately maintaining the oil feed amount, the liquid column 20 is formed in a constant flow between the intervals X.

Therefore, the output wave transmitted from the ultrasonic sensor 10 is reflected by the surface 41 of the object to be ground 40 and received again by the sensor 10, and the received signal is transmitted and received through the electric wire 13 to the transmitter / receiver 11 and the controller. 12 is transmitted. The ultrasonic sensor 10 repeats transmission and reception after a certain time, and the control device 12 is notified each time, and calculates the grinding allowance in the time interval to obtain a measured value.

FIG. 3 is a schematic front view showing a main part of an ultrasonic sensor 10 according to another embodiment of the present invention. The ultrasonic waves transmitted from the sensor 10 into the liquid column 20 are to be ground 40. The light is reflected by the bottom surface 42 of the sensor and received by the sensor 10. The transmission / transmission signal is arithmetically processed in the control device 12, the time between transmission and reception is first measured, and then the difference from the reflected wave from the surface 41 of the object to be ground 40 described in FIG. The measured value of the plate thickness 43 of the grinding body 40 is obtained.

Further, FIG. 4 is a schematic front view showing the structure of an ultrasonic wave 10 according to another embodiment of the present invention. The ultrasonic sensor 10 is surrounded by a nozzle 21 and the nozzle 2
1 is arranged facing the grinding surface 31 of the grindstone 30. Similar to the above, the grinding fluid 25 is introduced into the nozzle 21 through the inlet 22 to generate the liquid column 20. The output wave transmitted from the ultrasonic sensor 10 in the liquid column is the grinding surface 31 of the grindstone 30.
Is transmitted to the transmitting / receiving device 11 via the electric wire 13. By calculating the reflection time of the output wave repeatedly transmitted at a constant time interval, the grindstone 3 worn within the interval is calculated.
A measured wear allowance of 0 is calculated. Therefore, the control device 12
As a result, the grinding feed allowance of the grindstone 30 can be controlled in accordance with the wear allowance, or a replacement warning of the grindstone 30 can be issued according to the set value.

Although the embodiment according to the present invention has been described with respect to the grinder, the same action and effect as described above can be obtained in a cutting machine.

[0020]

As described above, according to the present invention, a liquid column is generated between the ultrasonic sensor and the reflecting surface on the side of the work piece or the machining tool, and the time of the ultrasonic wave reciprocating in the liquid column is reduced. Since the measurement is configured, the in-process measurement of the grinding allowance of the work piece and the dimension of the work piece can be performed, and particularly in the grinding process, the in-process measurement of the wear allowance of the grinding surface of the grindstone becomes possible. Moreover, since the frequency of the ultrasonic waves is set to 1 MHz or higher, the accuracy of measurement is equal to or higher than that when transmitting and receiving in the air, even though the ultrasonic transmission medium is liquid or solid. It becomes possible to obtain. Moreover, since the liquid column is generated by the processing oil used for the processing work, it does not interfere with the processing work, and further, the processing oil is discharged from the nozzle to the reflecting surface. It is possible to eliminate the machining waste on the reflecting surface and the generation of noise due to this, and it is possible to provide a non-contact measuring device for a workpiece with high measurement accuracy.

[Brief description of drawings]

FIG. 1 is a schematic front view showing the configuration of an ultrasonic sensor according to an embodiment of the present invention.

FIG. 2 is a front view showing a configuration of a surface grinder used in an embodiment of the present invention.

FIG. 3 is a schematic front view showing the configuration of an ultrasonic sensor according to another embodiment of the present invention.

FIG. 4 is a schematic front view showing the configuration of ultrasonic waves according to another embodiment of the present invention.

[Explanation of symbols]

 10 Ultrasonic Sensor 20 Liquid Column 21 Liquid Supplying Means 25 Processing Oil 30 Processing Tool 31 Reflective Surface of Grinding Wheel 40 Workpiece 41 Reflective Surface of Workpiece 42 Reflective Surface of Workpiece 43 Dimension of Workpiece

Claims (7)

[Claims] 1. An ultrasonic wave is output from an ultrasonic sensor mounted on the side of a machining tool or a work piece and a reflective surface on the side of the work piece or the work tool in a state where a liquid column is generated. Then, the machining allowance or the dimension of the workpiece is measured by utilizing the reflection time of the output wave 2. The non-contact measuring method for a work piece according to claim 1, wherein the frequency of the ultrasonic waves is 1 MHz or more. 3. The non-contact measuring method for a work piece according to claim 1, wherein the liquid that forms the liquid column is the same liquid as the processing oil. 4. The machining tool is a cutting tool.
Non-contact measuring method of the work piece described 5. The processing tool is a grinding wheel.
Non-contact measuring method of the work piece described 6. An ultrasonic sensor mounted on the machining tool side or the workpiece side facing the reflection surface on the workpiece side or the machining tool side, and a liquid supply means arranged so as to surround the outer circumference of the sensor. A non-contact measuring device for a workpiece, which is configured to generate a liquid column between the ultrasonic wave output part of the sensor and the reflecting surface by using the supply liquid from the supply means. 7. An ultrasonic sensor attached to the main body of the apparatus,
Grinding wheel wear characterized by producing ultrasonic waves from the sensor in a state where a liquid column is generated between the grinding surface of the grinding wheel and measuring the wear allowance of the grinding wheel using the reflection time of the output wave Cost measurement method