JPH0719841A - Noncontact surface roughness measuring apparatus - Google Patents

Abstract

PURPOSE:To provide a noncontact surface roughness measuring apparatus, which can measure the degree of the stripe-shaped irregularities such as the machining streaks and the like of a material to be machined during processing in real time even under the environment wherein vibrations and dust are more. CONSTITUTION:A light beam L0 is cast on a surface to be measured M4 having stripe- shaped irregularties M2 from the light source of a noncontact surface roughness measuring apparatus in the approximately vertical direction A0. The intensities of reflected lights L1 and L2 in the direction forming an angle theta with the irradiation direction A0 of the light beam are detected with light receiving means S1 and S2 for the longitudinal direction A1 of the stripe-shaped irregularities M2 and the direction A2, which orthogonally intersects the direction A0. The rate of the dispersion of the reflected light of the light beam L0, which is applied on the surface to be measured M4 approximately orthogonally, becomes the largest value in the direction A2 and becomes the smallest value in the direction A1. The difference DELTAS between the intensities of the reflected lights in two directions is used as a key. A map M6, wherein the corresponding relation of the difference DELTAS of the intensities of the reflected lights and the surface roughness of the surface to be measured, is reflected to, and the surface roughness of the surface to be measured M4 is computed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type surface roughness measuring device for measuring the surface roughness of a machined product in a non-contact manner. In particular, the present invention relates to a device for measuring the surface roughness of a surface to be measured having streaky irregularities by using the reflected light intensity of a light beam applied to the surface to be measured.

[0002]

2. Description of the Related Art In machining processes such as cutting, grinding and lapping, it is sometimes necessary to determine subsequent machining conditions and machining time depending on the finish of the surface of the workpiece.
In particular, in recent high-speed precision machining, in order to perform precise finishing in a short time while feedback-controlling machining conditions, etc., a means capable of measuring the surface condition of the workpiece being machined in real time with high precision is required. ing. Conventionally, as a device for measuring surface roughness, a stylus (stylus) is moved while being in contact with the surface of the object to be measured, and the vertical movement of the stylus is converted into an electric signal to measure the surface roughness. A stylus-type surface roughness measuring device for measuring has been used. This stylus type surface roughness measuring device can detect even minute irregularities on the surface to be measured with high accuracy. It is also possible to obtain three-dimensional data (that is, two-dimensional distribution of surface roughness) on the measured surface by moving the stylus two-dimensionally on the measured surface.

However, since such a stylus type surface roughness measuring device cannot measure at a place where there is much vibration or dust due to its mechanism, it is difficult to apply it to a site where cutting or grinding is performed. Further, it takes about 30 minutes to measure an area of 1 mm ² , which cannot be used for real-time measurement of the surface condition of a workpiece being processed. In contrast to such a conventional surface roughness measuring device, in recent years, a light reflectance non-contact method for measuring the surface roughness using the relationship between the surface roughness of the measured surface and the distribution of the light reflection angle on the measured surface. Surface roughness measuring devices have been developed. As such a light reflectance type non-contact type surface roughness measuring device, the present applicant has filed Japanese Patent Application No. 4-1.
No. 44288 is filed. A feature of this method is that the roughness of the surface of the work piece can be measured in real time, without damaging it, and without limiting the measurement site. In addition, it is easier to maintain the performance compared to wear and chipping of the stylus of the stylus type.

The measurement principle of such a light reflectance type non-contact type surface roughness measuring apparatus will be described with reference to FIGS. 13 and 14. 13 and 14 are explanatory views showing the measurement principle of the light reflectance type surface roughness measuring device. Figure 1
3A is a diagram showing an angular distribution of the reflected light 104A when the light beam 102A is applied to the surface to be measured 100A having a rough surface, and FIG. 13B is a surface to be measured having a smooth surface. It is a figure showing angular distribution of reflected light 104B when 100B is irradiated with light beam 102B. As shown in FIGS. 13A and 13B, when the surface is irradiated with light, the spread of the reflected light becomes larger as the surface roughness becomes rougher and becomes smaller as the surface becomes smoother. That is, the rougher the surface roughness, the greater the proportion of the reflected light in the direction inclined by a certain angle θ with respect to the perpendicular to the surface to be measured. Therefore, the value of the ratio (Fθ / F0) = FD of the reflected light amount F0 in the perpendicular direction of the measured surface and the reflected light amount Fθ in the inclined direction is the surface roughness R
It has a certain correlation with a. It is experimentally known that this correlation is represented by a curve as shown in FIG. 14, and is given by the following equation (1). FD = M + Klog (Ra) (1) Here, M and K are constants that differ depending on the material of the object to be measured, processing conditions, and the like. The surface roughness is measured by the light reflectance type non-contact type surface roughness measuring device using such a correlation.

A specific configuration of the light reflectance type non-contact type surface roughness measuring apparatus will be described with reference to FIG. FIG. 15 is a block diagram showing a measuring mechanism of a light reflectance type non-contact type surface roughness measuring device. As shown in FIG. 15, this surface roughness measuring device calculates an optical fiber head 44 for measuring a light reflectance, which includes a light source 60 and two optical fibers 63, 64, etc., and processes the measurement signal thereof. The signal processing unit 80 is mainly configured. The first optical fiber 63 is attached along the axis of the optical fiber head 44, and at the time of measurement, the surface 52 of the DUT 50 is measured.
Is set to be perpendicular to. Meanwhile, the second
The optical fiber 64 is attached to the first optical fiber 63 so that its central axis forms an angle of about 30 degrees. These two optical fibers 63 and 64 include the input optical fibers 61 and 62 and the output optical fibers 65 and 66.
, But each is optically connected. Each of the two optical fibers 63 and 64 has an optical path for input provided at the center thereof, and an optical path for output provided around it.

The input optical fibers 61 and 62 are both optically connected to the light source 60, and the output optical fibers 65 and 66 are optically connected to the light receivers 67 and 68, respectively. . From the light receivers 67 and 68, electric signals corresponding to the intensity of the received light are sent to the signal lines 69 and 70.
Are output through the amplifiers 71 and 72.
Are amplified respectively. The optical input signal F0 to the first optical fiber 63 amplified by the amplifier 71 and the amplifier 7
The optical input signal F to the second optical fiber 64 amplified by 2
Both θ are input to the divider 74. In the divider 74, the ratio of the two optical input signals F0 and Fθ is F
θ / F0 is calculated. The ratio (Fθ / F0) = FD of the two optical input signals thus obtained is input to the antilog amplifier 76, and the inverse logarithm of FD is calculated. The antilogarithmic operation in the antilog amplifier 76 is executed according to the following equation (2) obtained from the above equation (1). Ra = 10exp {(FD-M) / K} (2) As a result, the value of the surface roughness Ra is obtained based on the relationship shown by the curve in FIG.

These measurement and calculation processes are performed at a plurality of points on the surface to be measured in order to reduce the measurement error, and a plurality of surface roughness Ra values are obtained. Then, the average value calculator 78 calculates the average value of the plurality of surface roughness Ra, and outputs it as the final value of the surface roughness Ra. The non-contact type surface roughness measuring device using such light reflectance can measure anywhere without damaging the object to be measured. In addition, since the Ra (center line average roughness) value in the light spot with a diameter of about 1.5 mm is measured at one place, the same area as that of the conventional stylus type surface roughness measuring device is measured. Can be measured in a short time.

[0008]

However, in order to control the processing conditions in high-speed precision processing by measuring the surface roughness and improve the processing accuracy and processing efficiency, the surface condition of the workpiece being processed must be Three-dimensional data is needed. For example, in grinding and lapping, it is necessary to measure how much machining streaks remain and change the lapping conditions and the machining time accordingly. On the other hand, in the above-mentioned light reflectance type surface roughness measuring device, the average Ra (center line average roughness) in the light spot is measured.
However, there is a problem in that it is not possible to obtain information about streaky irregularities such as machining scratches, unlike the conventional stylus-type or photo-stylus-type surface roughness measuring device. there were. Therefore, in the present invention, it is an object of the present invention to provide a non-contact surface roughness measuring device capable of measuring in real time the surface roughness of a surface to be measured having streak-like irregularities such as machining marks on a workpiece being processed. And

[0009]

In order to solve the above problems, the present invention provides a non-contact type surface roughness measuring apparatus for measuring the surface roughness of a surface to be measured having streaky irregularities. , A light source that emits a light beam from a direction substantially perpendicular to the surface to be measured, and the same angle with respect to the irradiation direction of the light beam for each of the longitudinal direction of the streaky unevenness and the direction orthogonal thereto. The light receiving means for detecting the intensity of the reflected light in the direction forming the, and the ratio of the intensity of the reflected light in the two directions as a key, the surface roughness of the surface to be measured having the ratio of the intensity of the reflected light and the streaky unevenness in advance A non-contact surface roughness measuring device having a calculation means for calculating the surface roughness of the surface to be measured is created by referring to a map stored in association with and.

[0010]

The operation of the non-contact type surface roughness measuring apparatus of the present invention having the above construction will be described with reference to FIG. Figure 1
FIG. 4 is a schematic diagram for explaining the operation of the non-contact type surface roughness measuring device of the present invention. Now, as shown in FIG. 1, the non-contact type surface roughness measuring device of the present invention has a stripe-shaped unevenness M2.
Is a non-contact type surface roughness measuring device for measuring the surface roughness of the surface M4 to be measured. By the light source of this non-contact type surface roughness measuring device, a direction A substantially perpendicular to the surface M4 to be measured is obtained.
The light beam L0 is emitted from 0. And the light receiving means S
1 and S2, with respect to the longitudinal direction A1 of the stripe-shaped unevenness M2 and the direction A2 orthogonal thereto, the irradiation direction A of the light beam
Reflected lights L1 and L in a direction forming the same angle θ with respect to 0
Two intensities are detected respectively.

Here, the rate at which the reflected light of the light beam L0 irradiated substantially perpendicularly to the surface M4 to be measured is scattered in directions other than the substantially vertical direction A0 is orthogonal to the longitudinal direction of the stripe-shaped irregularities M2. It becomes the largest in the direction A2. FIG. 13
This is because the streaky unevenness M2 contributes most to the direction A2 with respect to the effect of the scattering described in the above. On the other hand, in the longitudinal direction A1 of the stripe-shaped unevenness M2, the proportion of the reflected light of the light beam L0 scattered in directions other than the substantially vertical direction A0 is the smallest. The difference in the intensity of reflected light in the directions other than the substantially vertical direction A0 with respect to these two directions increases as the number, width, depth, etc. of the stripe-shaped irregularities M2 increase. Therefore, the difference ΔS in the intensities of the reflected lights L1 and L2 at the same angle θ in the two directions A1 and A2 and the surface roughness of the measured surface M4 having the streaky irregularities M2 have a certain fixed relationship. It will be. The correspondence between the difference ΔS in reflected light intensity and the surface roughness of the surface to be measured is stored in the map M6 in advance. Therefore, the calculating means detects the two directions A1, A detected by the light receiving means S1, S2.
The surface roughness of the measured surface M4 is calculated by referring to the map M6 using the difference ΔS between the intensities of the reflected lights L1 and L2 for the second light as a key.

By carrying out such a measuring method, it is possible to obtain the measurement result without damaging the object to be measured, without limiting the measurement site and in a short time. Then, as described above, the surface roughness of the surface to be measured having streaky irregularities is measured with high accuracy by using the difference in reflected light intensity in the two directions. In this way, the non-contact type surface roughness measuring device is capable of measuring the surface roughness of the surface to be measured, which has streaky irregularities such as machining scratches, in real time for the workpiece being processed.

[0013]

【Example】

First Embodiment Next, a first embodiment embodying the present invention will be described with reference to FIGS. First, the measurement principle of the non-contact surface roughness measuring apparatus in Example 1 will be described with reference to FIGS. FIG. 2 is a diagram showing the state of the surface to be measured and the measurement position in the non-contact type surface roughness measuring apparatus of this embodiment. 3 and 4 are explanatory views showing the measurement principle of the non-contact type surface roughness measuring apparatus of this embodiment. As shown in FIG. 2, what is to be measured in the non-contact type surface roughness measuring apparatus of the present embodiment is the degree of the machining scratch 54 formed on the surface 52 of the object 50 to be measured by grinding or the like. The degree of the machining scratches 54 refers to the number of the machining scratches 54, the width W and the depth D of the machining scratches 54, and the like. Here, the average surface roughness in the light spot is measured only by measuring several points on the surface 52 to be measured by the above-described light reflectance type surface roughness measuring device, and the desired processing is performed. No information is available on the extent of streak 54.
Therefore, in the present embodiment, the degree of the machining scratches 54 is measured as described below.

The optical fiber head 44 of the above-described optical reflectance type surface roughness measuring device shown in FIG. 15 is oriented in the direction shown in FIG. Consider the case of placement. As described with reference to FIG. 1, at this time, the amount of reflected light that is incident on the second optical fiber 64 that is tilted is maximized. On the other hand, when the optical fiber head 44 is arranged in the direction shown in FIG. 4 with respect to the processed groove 54, the amount of reflected light incident on the second optical fiber 64 becomes the smallest. Furthermore, the difference in the amount of reflected light incident on the second optical fiber 64 in these two cases is
It becomes larger as the number, width, and depth of the processing scratches 54 increase. Then, the measured value of the surface roughness by the light reflectance type surface roughness measuring device is calculated based on the magnitude of the reflected light amount. Therefore, the optical fiber head 4 of FIGS.
The difference in the surface roughness values measured by the arrangement of No. 4 also has a correlation with the degree of the machining scratch 54.

The correlation between the difference in the measured values of the surface roughness in the two directions and the degree of the machining scratch is shown in FIG.
This will be described with reference to FIG. FIG. 5 is an explanatory diagram showing the correlation between the difference in surface roughness in two directions and the degree of the machining streak in the non-contact type surface roughness measuring device of this embodiment. Now, Figure 2
Consider the measurement direction X and the measurement direction Y in.
Here, the measurement direction of the optical fiber head 44 means the S direction in FIGS. 3 and 4. As described above with reference to FIGS. 3 and 4, the measurement direction X,
Regarding Y, the amount of reflected light input to the second optical fiber 64 is larger in the case of the measurement direction X. Therefore, the ratio FD of the inputs to the two optical fibers also becomes larger in the measurement direction X, and the surface roughness R calculated according to the above-mentioned equation (2).
The value of a also becomes large. That is, as shown in FIG. 5A, the value of the surface roughness Ra = RaX in the measurement direction X becomes larger than the value of the surface roughness Ra = RaY in the measurement direction Y. Then, as described above, the difference between the surface roughness Ra in these two directions, that is, (RaX-Ra).
The value of Y) is, as shown in FIG.
It has a certain correlation with the degree of 4. By experimentally obtaining the curve shown in FIG. 5B in advance,
From the measured values of the surface roughness in the two directions X and Y in FIG. 2, it is possible to quantitatively determine the degree of the machining scratches 54.

Now, regarding the specific configuration of the non-contact surface roughness measuring apparatus of this embodiment based on such a measurement principle,
This will be described with reference to FIGS. FIG. 6 is a front view showing the overall configuration of the non-contact surface roughness measuring apparatus of this embodiment. Further, FIG. 7 is a front view showing a measuring unit portion of the non-contact surface roughness measuring apparatus of this embodiment, and FIG. 8 is a side view thereof. Since the internal structure of the optical fiber head and the processing means of the measured data in this embodiment are the same as those of the conventional example shown in FIG. 15 described above, detailed description will be omitted and FIG. 15 will be used as necessary. To do. As shown in FIG. 6, the non-contact surface roughness measuring device 1 of the present embodiment is mainly composed of the measuring unit 2 and the control unit 82.

The measuring unit 2 comprises a measuring unit body 10
And an actuator mounting portion 4 and a pair of measuring head leg portions 12A and 12B. The lower end of the measuring unit 10 is a measuring head portion 8, and the measuring head portion 8 has a conventional optical fiber head 44 described with reference to FIG.
A measuring head having a built-in optical fiber head similar to the above is provided. The measurement unit body 10 is attached to an actuator such as an arm of an automatic robot (not shown) at the actuator attachment portion 4,
It enables three-dimensional movement. Further, by bringing the pair of measuring head legs 12A and 12B into contact with the surface of the object to be measured, the measuring head portion 8 can be positioned at a predetermined distance from the surface to be measured. Measuring head legs 12A, 12B
The shape and the like are selected according to the shape of the object to be measured.

The measuring unit 2 and the control unit 82 are connected by the signal cable 6. The measurement signal output from the measurement head unit 8 is input to the control unit 82 through the signal cable 6 (corresponding to the signal cables 69 and 70 in FIG. 15). In the control unit 82, a signal processing unit similar to the signal processing unit 80 shown in FIG. 15 and a data processing unit (not shown) for processing the measurement data output from this signal processing unit are provided. This data processing unit is a computer system mainly composed of a CPU (central processing unit) and RAM, ROM memory devices. Further, as shown in FIG. 6, the control unit 82 has a display section 84 for outputting and displaying setting conditions and data processing results, and a plurality of setting buttons 86 for inputting and setting measurement conditions and the like.
With the configuration described above, the data measured by the measurement unit 2 is processed by the signal processing unit and the data processing unit of the control unit 82 according to the procedure described later, and is displayed as data indicating the degree of the machining scratch on the surface to be measured. The output is displayed on the section 84.

Next, the structure of the measuring unit 2 of the non-contact surface roughness measuring apparatus 1 of this embodiment will be described in detail with reference to FIGS. 7 and 8. As shown in FIG. 7, the measuring unit 2 of the non-contact type surface roughness measuring apparatus 1 of the present embodiment.
Has a structure in which a measuring head 40 having an optical fiber head 44 is attached to a U-shaped main body 10 via a driving device 30. The measuring device body 10 includes a pair of legs 1.
2A and 12B, and there is a space 14 between the legs 12A and 12B. The measuring head 40 is attached to the space 14. Specifically, the drive device 30 is attached to the measuring device main body 10 with the connecting bolt 24, and the connecting bolt 24 is fitted into the through hole 16 provided in the measuring device main body 10 and having a step. From the washer 22 engaged with the stepped portion of the through hole 16, the adjustment bolt 20
Is extended, and the adjusting bolt 20 is screwed into the female screw portion at the upper end of the connecting bolt 24. The connecting bolt 24 is fastened and fixed to the lower surface of the measuring device body 10 by two fixing nuts 26.

A male screw portion 24a at the lower end of the connecting bolt 24
Is screwed into a female screw portion (not shown) provided on the upper surface of the drive device 30. The drive device 30 includes a rotary motor 32, and a rotary shaft 34 of the rotary motor 32.
A disc 36 is fixed to the lower end of the. The measuring head 40 is attached by a mounting rod 38 at one point on the lower surface of the disc 36. The measuring head 40 has an optical fiber head 44 attached to the lower end of the measuring head body 42. Then, the lower end of the optical fiber head 44 is set to be separated from the measured object surface 52 by a predetermined distance δ in a state where the pair of leg portions 12A and 12B of the measuring device main body 10 are in contact with the surface 52 of the measured object 50. Has been done. With the above structure, the rotation shaft 32 is rotated by the rotation of the rotation motor 32.
When the disc 36 rotates integrally with the measuring head 4, the measuring head 40 makes a circular motion about the rotating shaft 34. As a result, the tip of the optical fiber head 44 is attached to the surface 52 of the measured object.
On the other hand, while moving at a predetermined interval δ, it moves in a circle.

Next, a method of processing measured data in this embodiment will be described. With the circular movement of the optical fiber head 44 by the rotating mechanism of FIGS. 7 and 8, the measurement is performed by the optical fiber head 44 at predetermined time intervals. These multiple measurement data are captured in the control unit 82 shown in FIG. 6 as measurement data combined with the angle of the circular movement. Here, the data for one round of circular movement of the optical fiber head 44 is considered in the data processing unit within the control unit 82. At this time, according to the description of FIG. 3 described above, the angle at which the amount of reflected light incident on the second optical fiber 64 is the largest in the data for one round is the angle of the optical fiber head 44 with respect to the processing scratch 54. It can be seen that this is the angle at which the measurement direction is vertical. As a result, from the data for one round, the measurement direction of the optical fiber head 44 is perpendicular to the machining scratch 54 (that is, FIG.
Measurement data in two directions, i.e., X direction) and a parallel direction (Y direction in FIG. 2). The measurement data of the two directions is arithmetically processed by the signal processing unit 80 of FIG. 15, and the measurement value of the surface roughness Ra in the two directions is calculated.

Then, the control unit 82 shown in FIG.
In the data processing unit, the difference between the surface roughness Ra in the two directions is obtained and collated with the correlation data (corresponding to FIG. 5B) stored in advance in the ROM of the data processing unit. As a result, the measurement data of the surface roughness Ra in the two directions is converted into the data regarding the degree of the machining streak, and is output as the final result. The output data of the machining scratches on the surface to be measured is output and displayed on the display section 84 of the control unit 82. In this way, in the non-contact surface roughness measuring apparatus 1 of the present embodiment, it is possible to measure the workpiece 50 being machined in real time and obtain information about the machining scratches 54 on the measured surface 52. it can.

Second Embodiment Next, a second embodiment embodying the present invention will be described with reference to FIGS. 9 and 10. FIG. 9 is an enlarged view showing the structure of the measuring head in the second embodiment of the non-contact type surface roughness measuring device according to the present invention. FIG. 9 (A) is a front view showing the tip portion of the measuring head, and FIG. 9 (B) is a bottom view thereof. In the non-contact surface roughness measuring device of the present embodiment, unlike the first embodiment, the measurement is performed with the measuring head fixed without moving. As shown in FIG. 9, the measuring head 140 of the present embodiment has a structure in which six optical fiber heads 144A to 144F are attached to the measuring head main body 142. The structure of each optical fiber head is the same as that of the optical fiber head 44 of the first embodiment, and two optical fibers 163 and 164 are provided inside each of the optical fiber heads 144A to 144F. The first optical fiber 163 is attached vertically along the axis of the measuring head 140, and the second optical fiber 164 is attached so that its central axis forms an angle of about 30 degrees with respect to the first optical fiber 163. Has been. The connection of the light source and the processing means of the measurement signal are the same as in the first embodiment.

Here, as shown in FIG. 9 (B), three of the six optical fiber heads 1 are used.
44A to 144C are attached so that the measurement direction is oriented in the left-right direction in FIG. 9, and the other three optical fiber heads 144D to 144F are attached so that the measurement direction is oriented in the vertical direction in FIG. There is. Now, in the non-contact type surface roughness measuring apparatus of the present embodiment having the measuring head 140 having such a structure, the measuring head 140 is brought close to one position on the surface to be measured, and the six optical fiber heads 144A are arranged.
Simultaneous measurements at ~ 144F. Thus, the surface roughness data along the straight line connecting the optical fiber heads 144A to 144C is obtained, and the surface roughness data in the direction perpendicular to the surface roughness data is obtained from the optical fiber heads 144D to 144F. Therefore, from the surface roughness data in these two directions, the degree of the machining scratch 54 on the surface to be measured can be measured by using the relationship of FIG. 5 as in the case of the first embodiment. As described above, in this embodiment, the moving mechanism of the measuring head as in the first embodiment is not required,
Similar measurements can be made. Therefore, there are advantages that the structure of the device is simplified and maintenance is facilitated because there are few moving parts.

FIG. 10 is a bottom view showing another configuration example of the measuring head in the non-contact surface roughness measuring apparatus of this embodiment. In FIG. 10A, the measuring head main body 242
Is a square, and eight optical fiber heads 244 to 244 are attached to the measuring head main body 242 in a cross shape. Further, in FIG. 10B, eight optical fiber heads 344 to 344 are attached to the square measurement head main body 342 along the four sides of the square. In FIG. 10C, eight optical fiber heads 444 to 4 are provided for the circular measuring head main body 442.
44 are mounted along the four sides of the square. The various arrangements of the optical fiber heads can be properly used according to the shape of the surface to be measured as the measurement target. The plurality of measurement data obtained by the plurality of optical fiber heads (optical fiber heads 144A to 144C or 144D to 144F in FIG. 9) arranged in the same direction can be variously processed according to the purpose. For example, the average value of a plurality of measurement data in the same direction may be used as the surface roughness data in the direction, and the maximum value,
The minimum value may be used as the surface roughness data.

Third Embodiment Next, a third embodiment embodying the present invention will be described with reference to FIG. FIG. 11 is an enlarged view showing the tip partial structure of the measuring head in the third embodiment of the non-contact type surface roughness measuring device according to the present invention. In this embodiment, FIG.
1, three optical fiber heads 544-
544 is attached to the measuring head such that each tip face is arranged along the circumference. Therefore, when measuring the cylindrical object to be measured 550, the three optical fiber heads 544 to 544 can be positioned so that the tips of the three optical fiber heads 544 to 544 are equidistant from the surface to be measured 552. As a result, even with the cylindrical object to be measured 550, the measurement data at a plurality of points can be simultaneously captured under the same condition by setting the measurement head once. As described above, in the present embodiment, by using the measuring head in which the optical fiber heads 544 to 544 are arranged as shown in FIG. 11, it is possible to measure the surface of the cylindrical workpiece or the like with high accuracy. it can.

Fourth Embodiment Next, a fourth embodiment embodying the present invention will be described with reference to FIG. FIG. 12 is a diagram showing a moving mechanism of the measuring head and the object to be measured in the fourth embodiment of the non-contact surface roughness measuring device according to the present invention. In this embodiment, as shown in FIG. 12, a cylindrical object to be measured 650 is supported by a pair of support shafts 600A and 600B and is rotated by a rotation mechanism (not shown). On the other hand, the tip of the measuring head 644 attached to the moving mechanism (not shown) moves in the arrow V direction while rotating in the arrow W direction by the rotating mechanism (not shown). This measuring head 644 is
It has the same structure as the measurement unit 2 in the first embodiment. That is, when the measuring head 644 rotates in the W direction, the built-in optical fiber head moves along the circumference, and the data in two directions can be fetched from the measured data for one rotation. As described above, in this embodiment, the rotation of the optical fiber head due to the rotation of the measurement head 644 is combined with the parallel movement of the measurement head 644 and the rotation of the DUT 650, whereby the entire area of the cylindrical surface of the DUT 650 is combined. The measurement can be performed over a short time.

In each of the above embodiments, the first optical fiber is attached perpendicularly to the axis of the measuring head and the second optical fiber is attached at an angle of about 30 degrees. The angle of is not limited to this. Furthermore, although the reflected light is received by two optical fibers and the ratio of the reflected light intensities thereof is taken, it is essential to take the ratio with the reflected light intensity in the direction perpendicular to the axis of the measuring head. Not a requirement. That is, the reflected light may be received by only one optical fiber attached so as to form a predetermined angle with respect to the axis of the measuring head, and the reflected light intensities may be compared in two directions. The structure, shape, size, quantity, arrangement, material and the like of the other parts of the non-contact surface roughness measuring device are not limited to those of the above embodiments.

Furthermore, as an effect peculiar to each of the above embodiments, the ratio of the reflected light intensity received by the first optical fiber and the second optical fiber attached at an angle of about 30 degrees to the first optical fiber is calculated. By taking this, a measurement error due to the magnitude of the reflectance on the surface to be measured is eliminated, and high-precision measurement that is not affected by the material or the like of the measurement target becomes possible. Further, since the second optical fiber is attached at an angle of about 30 degrees with respect to the axis of the measuring head, the data in the 30 degree direction, which has a high correlation between the surface roughness and the reflected light intensity described in FIG. 13, is used. It is possible to measure with higher accuracy.

[0030]

INDUSTRIAL APPLICABILITY In the present invention, means for measuring the reflected light intensity in two directions on the surface to be measured having streaky irregularities, and the difference between the reflected light intensity in these two directions and the surface roughness of the surface to be measured. Since a non-contact surface roughness measuring device of a light reflectance method having a means for calculating the surface roughness by referring to a map in which The surface roughness of the surface to be measured, which has streaky irregularities such as streaks, can be processed without damaging the surface.
The measurement site can be measured in real time without limitation. This allows real-time information about the three-dimensional surface condition of the workpiece being processed to be captured in real time, even in an environment with a lot of vibration and dust such as when a normal processing device is installed. It becomes a very practical non-contact surface roughness measuring device that can adjust processing conditions and the like.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining the operation of a non-contact surface roughness measuring device of the present invention.

FIG. 2 is a schematic diagram showing a state of a surface to be measured and the like in Example 1 of the non-contact surface roughness measuring device of the present invention.

FIG. 3 is an explanatory diagram showing a measurement principle in Example 1 of the non-contact surface roughness measuring device.

FIG. 4 is an explanatory diagram showing a measurement principle in Example 1 of the non-contact surface roughness measuring device.

FIG. 5 is a diagram showing a correlation between a difference between measurement values in two directions and a degree of a machining scratch on a surface to be measured in Example 1 of the non-contact surface roughness measuring device.

FIG. 6 is a front view showing the overall configuration of Example 1 of the non-contact surface roughness measuring device.

FIG. 7 is a front view showing the structure of a measurement unit portion in the first embodiment of the non-contact surface roughness measuring device.

FIG. 8 is a side view showing the structure of the measurement unit portion in the first embodiment of the non-contact surface roughness measuring device.

FIG. 9 is a diagram showing a second embodiment of the non-contact surface roughness measuring device according to the present invention.

FIG. 10 is a diagram showing a second embodiment of the non-contact surface roughness measuring device according to the present invention.

FIG. 11 is a diagram showing Example 3 of the non-contact surface roughness measuring device according to the present invention.

FIG. 12 is a diagram showing Example 4 of the non-contact surface roughness measuring device according to the present invention.

FIG. 13 is an explanatory diagram showing a measurement principle of a conventional light reflectance type surface roughness measuring device.

FIG. 14 is an explanatory diagram showing a measurement principle of a conventional light reflectance type surface roughness measuring device.

FIG. 15 is a block diagram showing a measuring mechanism of a conventional light reflectance type surface roughness measuring device.

[Explanation of symbols]

 A0 A direction substantially perpendicular to the surface to be measured A1 Longitudinal direction of streaky unevenness A2 A direction orthogonal to the longitudinal direction of streaky unevenness L0 Light beam L1, L2 Reflected light M2 Streaky unevenness M4 Measured surface M6 map S1, S2 Light receiving means ΔS Difference in reflected light intensity in two directions

Claims (1)

[Claims] 1. A non-contact surface roughness measuring device for measuring the surface roughness of a surface to be measured having streaky irregularities, wherein a light beam is irradiated from a direction substantially perpendicular to the surface to be measured. A light source, a light receiving unit that detects reflected light intensity in a direction that forms the same angle with respect to the irradiation direction of the light beam in each of the longitudinal direction of the streaky unevenness and the direction orthogonal thereto, and the two directions With the ratio of the reflected light intensity to the key as a key, the measured surface is referenced with reference to a map in which the ratio of the reflected light intensity and the surface roughness of the measured surface having the streaky irregularities are associated and stored in advance. A non-contact type surface roughness measuring device having a calculating means for calculating the surface roughness of the.