JP6865441B2 - Optical inner surface measuring device - Google Patents

Description

In the present invention, an optical measuring probe is inserted into the inner peripheral surface or the inner diameter of the deep hole of the object to be measured, light is emitted to the inner surface or the bottom surface of the deep hole, and the reflected light is three-dimensionally captured to observe the internal shape and observe the internal shape. It relates to an optical inner surface measuring device for measuring dimensional and geometrical accuracy.

For example, the quality of processed finished dimensions and geometric accuracy of fuel injection nozzle parts of automobile engines have a great influence on the power performance and fuel consumption efficiency of automobiles, but these inspections are generally performed by roundness measuring machines and surface roughness meters. , It was inspected using a contact type measuring machine such as a length measuring machine using a liner scale. However, in recent years, an optical non-contact measuring machine has appeared for the purpose of not damaging the object to be measured.

As a means for observing or inspecting the inner surface of an object to be measured in a non-contact manner, diagnostic imaging technology (optical imaging technology) is a technology widely used in equipment machines, medical sites, and the like. For example, at a manufacturing site such as a precision instrument, as a method of inspecting the inner part of a deep hole and diagnosing an image, in addition to observing a camera with a general endoscope, an optical sensor irradiates the inner surface with light rays to determine the intensity of reflected light. A method is adopted in which the presence or absence of surface scratches is automatically inspected by judging with a computer.

On the other hand, in the medical field, X-ray CT, which allows tomographic images to be observed for observing the affected area inside the human body, nuclear magnetic resonance, and OCT images by an endoscope using the coherence of light (light interference using near-infrared light). Methods such as tomography) are being researched and utilized. Then, by utilizing these optical technologies in the field of mechanical devices, irradiating the inner peripheral surface of a mechanical part having a hole or a precise inner diameter with a light beam, observation of scratches on the inner peripheral surface or measurement of dimensions is being studied. Typical structures of these observation and measurement devices are as shown in Patent Documents 1 to 3, for example.

In the hole shape measuring method and measuring apparatus shown in Patent Document 1, a light beam passing through a slit is obliquely irradiated into the small diameter hole (1) of the object to be measured (2) in the document, and the small diameter hole (1) is irradiated. The light beam reflected from the inner peripheral surface was captured by a camera, and the shape accuracy of the small-diameter hole was read.
However, in this configuration, if the surface of the object to be measured is a smooth surface such as a ring gauge, measurement is possible, but since the light beam is emitted from an angle, it is a general mechanical part having a complicated shape. When making measurements, the camera cannot capture the correct shape because it is affected by the uneven shape of the inner surface of the small diameter hole (1), which diverges light rays and makes it difficult to obtain reflected light. It was impossible. In addition, even when the object to be measured (2) was longer than expected, the reflected light could not be captured and the measurement could not be performed.

Further, in the method of measuring the inner surface of the pore using the probe for optical imaging shown in Patent Document 2, the probe is inserted into the inner peripheral surface of the hole to be measured, and the light beam from the condensing lens (3) is converted into an optical path. The mirror (18) rotates 360 degrees, and the angle of the mirror changes due to a change in centrifugal force, and the emission angle of the light ray changes, so that the light ray is emitted in a three-dimensional direction and the three-dimensional shape is measured.
However, since the probe is inserted inside the object to be measured, the heat generated by the motor rotating inside the probe propagates to the object to be measured. Could not be measured.

In the measuring machine shown in Patent Document 3, the temperature difference between the ring gauge, which is the measurement standard for the inner diameter dimension, and the object to be measured (2) is measured with a thermometer (6), and the amount of thermal expansion due to this temperature difference is calculated. , The measurement dimension is corrected.
However, since the expansion of the object to be measured is not constant and changes in a complicated manner depending on the material and shape, it is difficult to make a correct correction. For example, a correct correction calculation at the 0.01 micrometer level and a highly accurate measurement have not been performed.

Japanese Patent Application Laid-Open No. 08-233545 Japanese Patent Application Laid-Open No. 2015-008995 Japanese Patent Application Laid-Open No. 05-31257

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to allow a measuring probe to enter an inner peripheral surface of an object to be measured, an inner diameter of a deep hole, or a hole of a long and bent pipe. Rotately radiate light rays to the inner peripheral surface or the bottom surface of a deep hole, collect the reflected light three-dimensionally, process it with a computer, observe three-dimensional image data, and measure dimensional measurement and geometric accuracy. Then, the influence of the mechanical vibration of the measuring probe itself that radiates light rays on the inner peripheral surface of the measurement and the shaft runout that occurs on the rotating shaft of the rotating radiating motor should be completely eliminated. Then, a more important requirement is to prevent the heat generated from the rotary motor from propagating to the object to be measured and its own rotating radiating portion. By solving these problems, we provide an optical inner surface measuring device that eliminates the variation in data due to temperature changes that was conventionally caused by the heat generated by the rotary motor, and enables accurate and precise three-dimensional accuracy measurement of the inner diameter and inner peripheral surface. It is to be.

One means for solving the above problems is to use a tube in an optical inner surface measuring device for observing the inner peripheral surface of an object to be measured and measuring dimensional accuracy by using an optical measuring method (optical interference method, spectral interference method, etc.). A gas having a built-in optical fiber and at least one or more optical path conversion means at the tip of the optical fiber and having a motor for rotationally driving the optical path conversion means in a tube, and a gas taken in from the tip side of the motor Exhaust from the front side of the motor through the tube, a hard translucent pipe is attached to the tip of the tube, the translucent pipe is inserted into the inner diameter of the object to be measured, and the light beam guided through the optical fiber is It is configured to be emitted from the optical path conversion means, irradiated to the circumferential surface of the object to be measured through the translucent pipe, and the reflected light is detected through the translucent pipe.

According to the present invention, since the optical probe for measurement can penetrate into the hole of the object to be measured and emit light rays, stable measurement can be performed without being affected by the surface shape and roughness, and the motor built in the optical probe can be used. It has a cooling function to prevent the propagation of heat generation, and the influence of bearing runout and vibration of the motor in the measurement probe can be eliminated by measurement using a translucent pipe, which is the standard for measurement. It is possible to measure the accuracy of the inner peripheral surface.

Configuration diagram of the optical inner surface measuring device according to the embodiment of the present invention. Cross-sectional view of the first optical probe of the optical inner surface measuring device Explanatory drawing of rotational operation of the optical probe Explanatory drawing of scanning angle of the same optical probe Explanatory drawing of scanning angle of the same optical probe Explanatory drawing of 3D scanning range of the same optical probe Explanatory drawing of calibration method of the optical probe Explanatory drawing of temperature change of the same optical probe Explanatory drawing of measurement variation of the same optical inner surface measuring device Cross-sectional view of the second optical probe of the optical inner surface measuring device Explanatory drawing of the load limiting mechanism of the slider for the same optical probe Explanatory drawing of operation when the load of the slider is over

The first feature of the optical inner surface measuring device of the present embodiment is the optical fiber built in the tube and at least one or more optical paths at the tip of the optical fiber in the optical inner surface measuring device for observing and measuring the object to be measured. It has a conversion means and has a motor in the tube that rotationally drives the optical path conversion means. The gas taken in from the tip side of the motor is exhausted from the front side of the motor through the tube, and the tip of the tube is hard translucent. A sex pipe is attached, the translucent pipe is inserted into the inner diameter of the object to be inspected, and the light beam guided from the optical fiber by the optical path conversion means emits a light beam in the circumferential direction through the translucent pipe, and the reflected light thereof. Is configured to be detected again through the translucent pipe.
With this configuration, the measuring probe can be penetrated into the hole of the object to be measured, and light can be emitted from near the hole at a substantially right angle to the inner peripheral surface, so that stable measurement can be performed without being affected by the surface shape and roughness. Further, the propagation of heat generated from the motor built in the optical probe can be prevented by the cooling action due to the inflow of gas. Further, the influence of bearing runout and vibration of the motor with a built-in optical probe, which is a cause of variation in measurement accuracy, can be eliminated by measuring the inner surface of the object to be measured with reference to the dimensions of the translucent pipe. As a result, it is possible to accurately and accurately measure the inner diameter and the accuracy of the inner peripheral surface.

The second feature is a first optical path conversion means that has a first motor and a second motor arranged on the rear side of the first motor and is operated by the first motor, and a second motor that is operated by the second motor. It has two optical path conversion means, and rotates integrally with the fixed-side optical fiber, which is non-rotatably arranged on the tube via a fixture on the rear side of the second motor, and the rotating shaft of the first motor or the second motor. Each of the rotating shafts of the first motor and the second motor has a hollow shape, and at least a part of the rotating shaft on the tip side rotates the first motor. It is rotatably inserted into the hollow hole of the shaft portion, and at least a part of the rear side is fixed to the hollow hole of the rotating shaft portion of the second motor. On the tip side, it is rotatably arranged integrally with the rotating shaft of the first motor, and the second optical path converting means is located at the tip of the rotating optical fiber and is between the first optical path converting means and the first motor. It is configured to be located.
With this configuration, light rays are emitted in the three-dimensional direction, and three-dimensional data of the inner peripheral surface of the object to be measured can be acquired and three-dimensional precise measurement of the inner peripheral surface can be performed.

The third feature is that the gas taken in from the tip side of the motor is guided to the front side of the motor via the gap between the rotating portion and the fixed portion of the motor in the tube, and is exhausted.
With this configuration, the motor coil portion, which is the heat generation source of the motor, can be directly cooled by the inflowing gas, so that the propagation of heat generation from the motor in the measurement probe can be prevented more reliably, and more precise accuracy measurement is possible. ..

The fourth feature is that at least one of the tube and the translucent pipe is fixed to the sliding member, and when the translucent pipe or the tube abuts on the object to be inspected, a contact load of a certain level or more is obtained. The sliding member slides together with the translucent pipe to prevent damage.
According to this configuration, the inner diameter and inner peripheral surface can be safely prevented from being damaged when the tube or translucent pipe, which has low strength and is easily damaged due to the intake hole, comes into contact with the object to be inspected. It is possible to measure the accuracy of.

Next, a preferred embodiment of the present invention will be described with reference to the drawings.

An embodiment of an optical inner surface measuring device according to the present invention will be described.
1 to 8 show an embodiment of the optical inner surface measuring device according to the present invention.

FIG. 1 is a configuration diagram of an optical inner surface measuring device according to an embodiment of the present invention. The stand 81 is fixed to the measuring machine base 80, and the slider 82 moves up and down together with the optical probe 34 by the slider motor 83. The object to be measured 100 is set on the measurement base 80, and the tip of the optical probe 34 or the translucent pipe 21 is configured to enter and exit the deep hole of the object to be measured 100. The light beam is applied to the inner peripheral surface of the object to be measured 100 through the translucent pipe 21 fixed to the tip of the tube 6, and the reflected light passes through the inside of the tube 6 through the translucent pipe 21 and is the fixed side optical fiber. Proceeding through 1, further passing through the connecting portion 84 of the measuring machine main body 85, entering the optical interference analysis unit 88, analyzing with the computer 89, and displaying the image or the measured numerical value on the monitor 90.

This optical inner surface measuring device has a diameter measuring function, a roundness measuring function, and a cylindricity measuring function obtained by displaying in three dimensions.

FIG. 2 is a cross-sectional view of the tip of the optical probe 34 of the optical inner surface measuring device according to the embodiment of the present invention. The fixed-side optical fiber 1 that guides a light beam from the rear end side to the front end side of the optical probe 34 is inserted into a sufficiently long tube 6 and fixed by the optical fiber fixture 4.

A rotating optical fiber 2 is rotatably arranged on the tip side of the fixed optical fiber 1. The first optical path conversion means 3a and 3b made of a substantially flat mirror or the like are rotatably attached to the tip side of the rotating side optical fiber 2 by the first motor 12 independently of the rotating side optical fiber 2 and rotate. It is configured to emit light rays in the entire circumference direction of 360 degrees.

The end faces of the rotating side optical fiber 2 and the fixed side optical fiber 1 face each other with a minute distance of about 5 microns, and the rotating optical connector 22 is composed of the rotating light-shielding plate 5 and the optical fiber fixture 4, and the rotating side optical fiber is formed. High transmittance can be maintained between 2 and the fixed-side optical fiber 1, and they are optically connected with almost no loss.

Further, at a position between the first optical path conversion means 3a and 3b and the first motor 12, the light rays transmitted through the fixed-side optical fiber 1 and the rotating light connector 22 are focused and rotated, and a slight angle is formed in the tip direction. A second optical path conversion means 20 that emits light rays toward the first optical path conversion means 3a and 3b is attached to the tip of the rotating optical fiber 2.

In the first motor 12, the first motor coil 7, the first bearings 9b, 9a, and the motor thrust plate 8 are fixed to the motor case 24, and the first hollow rotating shaft 10 to which the first rotor magnet 11 is attached rotates. A voltage is applied to the first motor coil 7 from the electric wire 17, and a first optical path conversion means 3 using a mirror or the like is attached to the rotating first hollow rotating shaft 10.

The second motor 19 is located behind the first motor 12, and the second bearings 16a and 16b and the second motor coil 15 are attached to the motor case 24. The second bearings 16a and 16b are the second rotor magnets 14. The second hollow rotating shaft 13 is rotatably supported, and a voltage is applied from the second electric wire 18 to rotate the shaft 13. A rotating side optical fiber 2 is inserted and fixed in the hole 13a of the second hollow rotating shaft 13, and a second optical path converting means 20 made of a prism or the like is attached to the tip thereof, and these rotate integrally. A part of the rotating optical fiber 2 is rotatably inserted into the hole of the first hollow rotating shaft of the first motor 12 and rotates relatively.

The first motor 12 and the second motor 19 are fixed to the motor case 24 with a gap by the fixing dowels 33a and 33b. At least one intake hole 6a is formed in the tube 6 or the translucent pipe 21 on the tip side of the first motor 12, and the pipe temperature sensor 31 is formed in the translucent pipe 21 or the tube 6. Is provided. In FIG. 1, an intake tube 29 and an intake fan 30 are attached to the tube 6, and gas is sucked from the intake hole 6a of FIG. 2, and the sucked gas is first exhausted from the intake fan 29. The motor 12 and the second motor 19 are cooled to prevent the heat generated from these motors from propagating to the translucent pipe 21 and the object to be measured 100, and the measurement dimensions of the object to be measured due to thermal expansion are prevented.

The first motor 12 of FIG. 2 is rotationally driven by being supplied with electric power from the first motor driver circuit 86 shown in FIG. 1, and the second motor 19 is rotationally driven by applying a voltage from the second motor driver circuit 87. ..

A translucent pipe 21 through which the light rays are transmitted is integrally attached to the tube 6 in the vicinity of the outer periphery of the first optical path conversion means 3 from which the light rays 26 and 27 are emitted. The inner peripheral surface or the outer peripheral surface of the translucent pipe 21 is coated, if necessary, to reduce surface reflection and increase the transmittance of light rays. Further, the first optical path conversion means 3 is composed of a rotatable mirror or prism, and has high reflection efficiency, reduces optical loss, and enables highly accurate measurement.

The second optical path conversion means 20 is composed of a prism or the like having a substantially flat surface inclined at the tip, has high light collecting property, reduces optical loss, and enables highly accurate measurement.

Next, the characteristic action and effect of the optical inner surface measuring device of FIG. 1 using the three-dimensional scanning type optical probe shown in FIG. 2 will be described in detail.

In FIGS. 1 and 2, a light ray such as a near infrared ray or a laser emitted from the inside of the measuring machine main body 85 passes through the fixed side optical fiber 1 built in the tube 6 and travels.

Power is supplied from the electric wires 17 and 18, and when the two motors of the first motor 12 and the second motor 19 rotate synchronously at the same rotation speed in the range of about 900 to 20,000 rpm, the guided light beam is a rotating optical connector. After passing through 22 and the rotating optical fiber 2, as shown in FIG. 2, it is emitted from the second optical path conversion means 20, reflected by a substantially flat portion of the first optical path conversion means 3a, and is reflected in a constant angular direction (θ1 in FIG. 2). The direction is changed to (angle), and the light is rotationally radiated in the direction of 360 degrees, and the radiation range at this time is an umbrella-shaped range at an angle θ1 as shown in FIG.

The light rays further pass through the translucent pipe 21, and the light rays reflected from the inner peripheral surface of the object 100 to be inspected are reflected in the same optical path as above in the opposite direction. Means 20 ⇒ Rotating side optical fiber 2 ⇒ Rotating optical connector 22 ⇒ Passing through the fixed side optical fiber 1 and guided to the optical interference analysis unit 88.

Next, the rotation speeds of the first motor 12 and the second motor 19 are, for example, the rotation speed of the first motor 12 is constant at 3600 rpm, while the rotation speed of the second motor 19 is constant at 3570 rpm, and these two motors are rotated. Switch to a rotation state that gives a slight difference in the number of rotations. In this state, as shown in FIG. 3, at the same time as the first optical path conversion means 3 rotates, the relative rotation angle phase with the second optical path conversion means 21 gradually changes, and eventually the light beam rotates in the first optical path conversion. The light beam reflected by the means 3 is emitted at 360 degrees in the entire circumferential direction, and the radiation angle in the longitudinal direction gradually changes as shown in θ2 in the figure of FIG. That is, the radiation range of the light beam at this moment is changed to the inclined umbrella-shaped scanning range as shown in FIG.

This rotation angle phase difference deviates by 30 rotations (that is, 3600-3570 = 30 rotations / minute), which is the difference from the rotation speed of the second motor 19 while the first motor 12 rotates 3600 rotations per minute. The rotation angle phase difference occurs 30 times per minute (that is, 30 reciprocations), and the rotation phase difference between the first optical path conversion means 3 and the second optical path conversion means 20 continues to slowly occur 30 times per minute. As a result, as shown in FIG. 6, the radiation direction of the light beam continuously changes in the range of θ1 to θ2, and the radiation range 79 of the light beam is repeatedly irradiated three-dimensionally in the range of θ1 + θ2.

In FIG. 2, the rotation pulse generator 28 generates one pulse per rotation of the first optical path conversion means 3 or the first hollow rotation shaft 10, and this pulse signal is sent to the first motor driver circuit of FIG. The rotation speed of the first motor 12 is adjusted, and the rotation speed is sent to the computer 89, which is used as a trigger signal for drawing a three-dimensional digital image frame by frame.

In the optical inner surface measuring apparatus of the present invention, the procedure for measuring the inner diameter 100a of the object to be measured 100 is as follows.

First, calibration is performed as a preparation before measurement. As shown in FIG. 7, the translucent pipe 21 of the optical probe 34 is inserted into the hole of the ring gauge 78 whose inner diameter (D1) is known, and the inner peripheral surface of the ring gauge 78 is inserted from the outer diameter of the translucent pipe 21. The radius difference (L1-L2) and (L1'-L2') up to, and the distances L1 and L1'from the inner peripheral surface of the ring gauge to the virtual midpoint of the optical probe 34 are obtained. Here, the radius values (R = D1 / 2- (L1-L2), R'= D1 / 2- (L1'-L2') of the translucent pipe 21 are obtained, and the reference radius values of R and R'are obtained. Is stored in the computer 89 as the reference radius data of the translucent pipe 21 to complete the calibration. This calibration is performed periodically about once a month.

After the calibration is completed, the measurement is started next. The translucent pipe 21 of the optical probe 34 is inserted into the inner peripheral surface 100a of another object to be inspected, the first motor 12 and the second motor 19 are rotated to emit light rays, and the inner diameter dimension of the object to be measured 100 (D). ) = R + (L1-L2) + R'+ (L1'-L2') can be obtained.

8 and 9 show, in FIGS. 1 and 2, a case where gas is sucked from the intake hole 6a and the first motor 12 and the second motor 19 are cooled by the operation of the intake fan 30, and the intake fan 30 is stopped. It shows the difference when it is not cooled. As shown in FIG. 8, the translucent pipe 21 rises by 0.5 ° C. in about 20 seconds with cooling, but then stops rising and maintains a constant temperature, and there is almost no temperature propagation to the object to be measured 100 and the temperature changes. The deviation of the measurement accuracy due to the above can be prevented. On the other hand, without cooling, the temperature of the translucent pipe 21 rises by 3 ° C. in about 1 minute and then gradually rises, and the temperature of the object to be measured 100 also starts to rise, so that it is difficult to perform highly accurate measurement.

FIG. 9 shows the magnitude of measurement variation when the inner diameter dimension of the object to be measured 100 is repeatedly measured by the inner surface measuring device of the present invention. The variation in the results of repeated measurements 100 times within 30 minutes under the condition of cooling (repetitive reproducibility: σ) was within 0.05 micrometers, and high-precision measurement was possible, but on the other hand, cooling Without the above, a variation of 0.15 μm occurred, and high-precision measurement was difficult.

By using the optical probe 34 shown in FIG. 2 in this way, the reflected light introduced from the inner peripheral surface 100a of the object to be measured 100 in FIG. 1 via the optical fibers 1 and 2 is calculated by the computer 89 to be transparent. Dimension measurement can be performed with reference to the optical pipe, three-dimensional data can be collected while the slider 82 is stationary, and heat generation from the motors 12 and 19 in the measurement probe 34 can be prevented from propagating, which is a conventional problem. It is possible to eliminate the influence of the bearing runout and vibration of the motor in the probe for measurement, and to measure the inner diameter and the inner peripheral surface accurately and accurately.

FIG. 10 shows a cross section of a second optical probe of the optical surface measuring device according to the present invention.
In FIG. 10, the motor case 24 is directly fixed to the inside of the tube 6, and the gas introduced from the intake hole 6a passes through the ventilation hole 8a appropriately provided in the motor thrust plate 8 and is at least the first motor 12. The first motor is configured to be efficiently cooled by passing through the gap between the first motor coil 7 and the first rotor magnet 11. Further, the second motor 19 is also configured so that gas can be passed through the gap between the second motor coil 15 and the first rotor magnet 14 as needed to further cool the second motor 19.

With this configuration, the gas taken in from the intake hole is guided to the front side of the motor (the measuring machine body side with respect to the tip side of the probe) via the gap between the rotating part and the fixed part of the motor in the tube, and the motor Since the motor coil portion, which is the heat generation source, can be directly cooled by the inflowing gas, the propagation of heat generation from the motor in the measurement probe can be reliably prevented, and more precise measurement can be performed.

In FIG. 10, other configurations and functions are the same as those of the first optical probe in FIG.

11 and 12 show a third embodiment of the optical surface measuring device according to the present invention.
In FIG. 11, the tube 6 having the ventilation hole 6a or the translucent pipe 21 made of thin-walled quartz or glass has a weak strength, and if it accidentally comes into contact with the object to be measured 100 during the measurement work, it will break and be damaged. There is a risk of doing. Therefore, as shown in FIG. 11, the tube 6 is slidably set on the probe fixture 37, and is fixed to the sliding member 38 pressed by the preload means 39a, 39b, 39c by, for example, a ball or the like to be measured. When it comes into strong contact with the object 100, for example, the load limiter 40 composed of a combination of a ball and a notch is disengaged, and the optical probe 34 slides upward in the drawing to prevent damage due to collision. ing. The magnifying glass (camera) 35 constantly displays the state of the object 100 in the vicinity of the hole 100a on the monitor 90, and warns the user of the measuring instrument not to collide with the optical probe 34.

According to this configuration, the optical probe 34 is fixed to the sliding member 38, and when the translucent pipe 21 or the tube 6 strongly abuts on the object to be measured 100, the sliding is performed by a contact load of a certain level or more. The member 38 can slide upward together with the translucent pipe 21 to prevent damage, and accurate and accurate measurement of the inner diameter and the accuracy of the inner peripheral surface can be safely performed.

In FIGS. 2 and 10, the diameter of the tube 6 is about 2 mm or less, and the fixed-side optical fiber 1 penetrating inside the tube 6 is a flexible glass fiber and has a diameter of 0.085 to 0.125 mm. The thing of the degree is adopted.

The first optical path converting means 3 is composed of a mirror or a prism having a smooth reflecting surface, and its surface roughness and flatness are polished to an accuracy equal to or higher than that of general optical components in order to increase the reflectance.

The first hollow rotary shaft 10 is made of metal or ceramics, and is hollow formed by drawing with a die of molten metal or extruding with a die of ceramics before firing, and is finished by a polishing method or the like after hardening. To.

Since the hole of the first hollow rotating shaft 10 has a diameter of 0.1 to 0.5 mm, which is sufficiently larger than the diameter of the rotating side optical fiber 2, the fixed side optical fiber 1 fixed by the optical fiber fixture 4 is the first. 1 There is no danger of contact with the hollow rotary shaft 10, and even if it is lightly contacted, wear powder is not generated. Further, there is no problem that the rotational friction torque fluctuates in this portion.

According to the present invention, by invading the measurement probe 34 into the hole of the object to be measured 100 and radiating light rays from the hole, stable measurement can be performed without being affected by the surface shape and roughness of the inner peripheral surface. Prevents the propagation of heat generated from the motors 12 and 19 in the optical probe 34. In addition, the influence of bearing runout and vibration of the motor inside the optical probe, which has been a problem in the past, can be eliminated, and by providing a load limiter to prevent damage to the optical probe, accurate and precise measurement of the inner diameter and inner peripheral surface. Can be done safely.

The optical inner diameter measuring device that observes and measures the object to be measured by using the optical measuring method of the present invention enables highly accurate three-dimensional observation and geometrical accuracy measurement of the inner surface of a deep hole. It is possible to perform high-precision measurement of industrial precision mechanical parts such as fuel injection parts and water jet nozzle parts. It is also expected to be used for numerical diagnosis and treatment of minute lesion dimensions in the medical field.

1 Fixed side optical fiber 2 Rotating side optical fiber 3a, 3b First optical path conversion means (mirror)
4 Optical fiber fixture 5 Rotating shield plate 6 Tube 6a Intake hole 7 1st motor coil 8 Motor thrust plate 9a, 9b 1st bearing 10 1st hollow rotating shaft 11 1st rotor magnet 12 1st motor 13 2nd hollow rotating shaft 13a Hole 14 2nd rotor magnet 15 2nd motor coil 16a, 16b 2nd bearing
17 Electric wire 18 Electric wire 19 Second motor 20, 20a, 20b Second optical path conversion means (prism, etc.)
21 Translucent pipe 22 Rotating optical connector (optical rotary connector)
23a Pulse generator 24 Motor case
25, 25a, 25b Scanning range 26, 27 Ray 28 Rotating pulse generator 29 Intake tube 30 Intake fan 31 Pipe temperature sensor 32 Work temperature sensor 33a, 33b Fixed dowel 34 Optical probe 35 Magnifier (camera)
37 Probe fixture 38 Sliding member 38a Notch 39a, 39b, 39c Preload means 40 Load limiter 78 Ring gauge 79 Scanning range 80 Measuring machine base 81 Stand 82 Slider 83 Slider motor 84 Connection part 85 Measuring machine body 86 First motor Driver circuit 87 Second motor Driver circuit 88 Optical interference analysis unit 89 Computer 90 Monitor 100 Object 100a Measured inner surface

Claims (4)

In an optical inner surface measuring device that observes and measures an object to be measured,
With the optical fiber built into the tube,
At least one optical path conversion means is provided at the tip of the optical fiber.
A motor for rotationally driving the optical path conversion means is provided in the tube.
The gas taken in from the tip side of the motor is exhausted from the front side of the motor through the tube.
The motor includes a first motor and a second motor arranged on the rear side of the first motor.
The optical path conversion means includes a first optical path conversion means operated by the first motor and a second optical path conversion means operated by the second motor.
The optical fiber is composed of a fixed-side optical fiber that is non-rotatably arranged in the tube via a fixture on the rear side of the second motor and a rotating-side optical fiber that is rotated by the second motor.
Rotary shaft portion of the rotary shaft portion and the second motor of the first motor is each a hollow shape,
At least a part of the rotary side optical fiber is rotatably inserted into the hollow hole of the rotary shaft portion of the first motor, and at least a part of the rear side is hollow of the rotary shaft portion of the second motor. It is fixed in the hole and
The first optical path conversion means is rotatably arranged on the tip side of the second optical path conversion means so as to be integrally rotatable with the rotation shaft portion of the first motor.
The second optical path conversion means is configured to be located at the tip of the rotating optical fiber and between the first optical path conversion means and the first motor.
A hard translucent pipe is attached to the tip of the tube.
Insert the translucent pipe into the inner diameter of the object to be measured,
The light beam guided from the optical fiber by the optical path converting means emits a light ray in the circumferential direction through the translucent pipe , and the reflected light from the object to be measured that receives the emitted light is detected again through the translucent pipe. An optical inner surface measuring device characterized by the above. The claim is characterized in that the gas taken in from the tip side of the motor is guided to the front side of the motor via a gap between a rotating portion and a fixed portion of the motor in the tube, and is forcibly exhausted. 1. The optical inner surface measuring device according to 1. In an optical inner surface measuring device that observes and measures an object to be measured,
With the optical fiber built into the tube,
At least one optical path conversion means is provided at the tip of the optical fiber.
A motor for rotationally driving the optical path conversion means is provided in the tube.
The gas taken in from the tip side of the motor is guided to the front side of the motor via the gap between the rotating part and the fixed part of the motor in the tube, and is configured to be forcibly exhausted.
A hard translucent pipe is attached to the tip of the tube.
Insert the translucent pipe into the inner diameter of the object to be measured,
The light beam guided from the optical fiber by the optical path converting means emits a light ray in the circumferential direction through the translucent pipe , and the reflected light from the object to be measured that receives the emitted light is detected again through the translucent pipe. An optical inner surface measuring device characterized by the above. In an optical inner surface measuring device that observes and measures an object to be measured,
With the optical fiber built into the tube,
At least one optical path conversion means is provided at the tip of the optical fiber.
A motor for rotationally driving the optical path conversion means is provided in the tube.
The gas taken in from the tip side of the motor is exhausted from the front side of the motor through the tube.
A hard translucent pipe is attached to the tip of the tube.
Insert the translucent pipe into the inner diameter of the object to be measured,
The light beam guided from the optical fiber by the optical path conversion means emits a light ray in the circumferential direction through the translucent pipe , and the reflected light from the object to be measured that receives the emitted light is detected again through the translucent pipe. ,
At least one of the tube and the translucent pipe is fixed to the sliding member, and when the translucent pipe or the tube abuts on the object to be measured, the sliding member is subjected to a contact load of a certain level or more. Is an optical inner surface measuring device characterized by sliding together with the translucent pipe to prevent damage.

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