JPH11230739A - Flatness measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flatness measurement device capable of easily measuring flatness without the need of huge man-hour, and obtaining high measurement accuracy even in a long-length component. SOLUTION: This flatness measurement device is provided with a wheel 5 moved along a scanning line, a main body 2 supported by two supporting legs 9 in contact with two points on the scanning line, a gyro 1 attached to the main body 2 for detecting the inclination angle of a straight line segment between the supporting legs 9 at respective parts in a scanning direction, and a computer 4 for calculating the flatness of a surface 100 to be measured based on the detection data of the inclination angle at the respective parts in the scanning direction inputted from the gyro 1. The flatness is measured from the detection data of the inclination angle at the respective parts on the scanning line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flatness measuring device for automatically measuring the flatness of a large-sized diesel engine, such as a canned part for a large diesel engine.

[0002]

Most of the main components, such as a crankcase and a base plate, forming the outer shell of a large diesel engine are made of cans. However, such large-sized crankcases and base plates made of canned parts are large and heavy, and in large diesel engines, a large load is applied due to the explosion pressure or supercharging air pressure. Since high airtightness is required for supercharged air, cooling water, and the like, it is required to maintain the flatness with high accuracy.

[0003] Conventionally, when measuring the flatness of a large-sized can-manufactured component for a large-sized diesel engine, as shown in FIG. The stretch 31 is placed on the surface 100, and a clearance gauge 32 is inserted into a gap between the stretch 31 and the surface to be measured 100, thereby detecting the gap between the two.

However, according to the prior art, when measuring the flatness of a large-sized part having a plane length of more than 2 m, such as the large-sized diesel engine can-made part, the flatness is measured. Long and heavy stretch 31
In addition, since the stretch 31 itself bends, the measurement operation is difficult, requires a large number of steps, and high-precision measurement is impossible.

In view of the problems of the prior art, the present invention provides a flatness measuring apparatus capable of easily measuring flatness without requiring a large number of man-hours and obtaining high measurement accuracy even for long parts. The purpose is to do.

[0006]

In order to solve the above-mentioned problems, the present invention provides, as a first invention, a flatness measuring apparatus which scans a surface to be measured and measures the flatness of the surface to be measured. A wheel to be moved along the scanning line, a main body supported by two supporting legs in contact with two points on the scanning line, and A gyro for detecting the inclination angle of the straight line segment, and the inclination angle detection data from the gyro are input, and the flatness of the surface to be measured is calculated based on the inclination angle detection data in each part in the scanning direction. A flatness measuring device characterized by comprising a computer that performs the measurement is proposed.

[0007] In a second aspect of the present invention, in the first aspect,
A computer is provided with a movement amount detector that detects a movement amount of the main body in the scanning direction of the surface to be measured, and in addition to the detection data of the inclination angle from the gyro, the computer detects the movement amount of the main body from the movement amount detector. The flatness of the surface to be measured is measured based on the detection data of the movement amount.

According to this invention, the main body on which the gyro is mounted or incorporated is moved by the wheels in the scanning direction on the surface to be measured, and a straight line segment in the scanning direction between the two support legs supporting the main body is provided. The tilt angle at each part in the scanning direction is
It is detected by a gyro, preferably a two-way gyro.
The detection data of the tilt angle is input to a computer, and the computer uses the detection data of the tilt angle to determine the amount of unevenness of the surface to be measured in each portion in the scanning direction,
That is, the flatness is calculated. The calculated flatness data is displayed on a display device or printed out.

Therefore, according to the invention, since the inclination angle of the surface to be measured is detected by the gyro, an error due to uneven scanning speed of the main body can be avoided, and high measurement accuracy can be obtained even in high-speed scanning. Even for large parts such as can parts for large diesel engines, the flatness can be measured automatically and with high accuracy.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. Only.

FIG. 1 is an overall configuration diagram of a flatness measuring device for parts for a large diesel engine according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a main part according to another embodiment of the flatness measuring device. 3 is a view taken in the direction of the arrow Z in FIG. 1 or FIG. 2, and FIG. 4 is an explanatory view of the principle of flatness measurement.

In FIGS. 1 and 3, reference numeral 2 denotes a main body, and 1 denotes a two-axis freedom gyro incorporated in the main body 2. The two-axis gyro 1 is a known gyro having two-axis (roll / pitch) degrees of freedom. The gyro 1 includes a rotor 30 having a driving unit that rotates at a high speed of about 24000 rpm, and a rotating shaft 31 of the rotor 30. A roll angle detection frame 11 for detecting a roll angle which is rotatably supported on a square, and the roll angle detection frame 11
A pitch angle detection frame 12 for detecting a pitch angle, which rotatably supports, and the pitch angle detection frame 12 is rotatably supported by the main body 2. Reference numeral 10A denotes a roll angle detector, which is provided on a bearing portion of a detection shaft of a pitch angle detection frame 12 that supports the roll angle detection frame 11, and 10B denotes a pitch angle detector.
The pitch angle detection frame 12 is attached to a bearing portion of a detection shaft with respect to the main body 2.

According to the gyro 1 having two degrees of freedom, the attitude change of the main body 2 can be detected as a pitch angle and a roll angle with reference to the rotation axis 31 of the rotor 30. In this embodiment, the biaxial degrees of freedom gyro 1 detects each change in the posture of the main body 2 that scans along the surface to be measured 100 of the member to be measured 150, as will be described in detail later. It has a function of obtaining the inclination of the main body 2 at a point with respect to the scanning direction.

5 is a wheel, 14 is an axle fixed to the wheel 5, and 9 and 9 are support legs fixed to the lower surface of the main body 2. As shown in FIG. 3, two support legs 9, 9 are provided at a distance (interval) L along the scanning direction of the measuring device. The wheel 5 is rotatable on the surface to be measured 100, and the direction of movement is parallel to the straight line connecting the centers of the two support legs 9, 9, ie, the scanning line 200, and the traveling direction of the wheel 5. Is mounted on an axle 14 which is supported by the main body 2 via a bearing 15.

Accordingly, the main body 2 is provided on the measured surface 1 of the wheel 5.
The support point is supported on the surface to be measured 100 at three points on the isosceles triangle of the contact point on the reference numeral 00 and the contact points of the two support legs 9, 9. The support legs 9, 9 are arranged so that the center of gravity of the main body 2 is located between the support legs 9, 9 and the wheel 5, so that the device does not roll over during operation.

Reference numeral 3 denotes a movement amount detector, which is fixed in the main body 2 by bringing a roller 13 for detecting the movement amount into contact with the side surface of the wheel 5. The movement amount detector 3 has a movement amount detection roller 13 attached thereto and is in contact with the outer peripheral side surface of the wheel 5 to detect the movement amount of the apparatus in the scanning direction from the rotation of the wheel 5.

Reference numeral 4 denotes a computer, and the moving amount detector 3
And the roll angle and the pitch angle detection signals from the angle detector 10 of the two-axis gyro 1 are input, and the inclination angle θ of the surface to be measured 100 in the scanning direction is calculated based on these signals. Further, as shown in the following mathematical formula, the calculation of the flatness Z of the measured surface 100 and the like are performed.

FIGS. 2 and 3 show another embodiment in which the gyro 1 is mounted on the main body 2 and the gyro 1 is fixed on the main body 2 as a base by bolts 16. . The wheel 5 is rotatable on the surface to be measured 100, and the direction of movement is parallel to the straight line connecting the centers of the two support legs 9, 9, ie, the scanning line 200, and the traveling direction of the wheel 5. So that the bearings 15a,
It is attached to an axle 14 that passes horizontally through the main body 2 that is pivotally supported via 15b. Reference numeral 3 denotes a movement amount detector, which is fixed to a portion of the upper surface of the main body 2 near the wheel 5 by a bolt 17 so that the roller 13 for detecting the movement amount contacts the side surface of the wheel 5. Other configurations are almost the same as those in FIG.

A measuring method for measuring the flatness of a large part for a diesel engine using the flatness measuring apparatus having the above-described configuration will be described. First, the principle of measurement will be described with reference to FIG. 6A. First, an origin is defined on the surface to be measured 100, the scanning (measurement) direction is set as the X axis, the distance from the origin is x, and the position of the distance x is set. If the angle of inclination of the surface at is θ,
The height of the unevenness of the measured surface 100, that is, the measured surface 100
Is expressed by the following “Equation 1”.

[0020]

(Equation 1)

Equation 1 is approximated and expanded as Equation 2 since | θ | << 1 (rad).

[0022]

(Equation 2)

If the integral calculation is performed by the difference method, the following equation (3) is obtained, and the calculation can be performed by a computer.
However, Δx is assumed to be sufficiently small.

[0024]

(Equation 3)

The distance L between the supporting legs for measuring θ is shown in FIG.
As shown in (B), the sampling theorem is shorter (shorter) than the half period of the unevenness, that is, shorter than two or more inflection points. In general, the interval Δx is smaller than the interval L between the support legs, and is preferably much smaller.
x << L, and set the inflection point within the interval of Δx to 1
Do the following.

According to the principle of measurement, the surface to be measured 100
When measuring the height of unevenness, that is, the flatness, the flatness measuring device is mounted on the surface 100 to be measured of the large-sized component, and the two support legs 9 are attached to the surface 100 to be measured. The contact is made, and the wheel 5 is rotated to move straight in the scanning direction. The rotation of the wheel 5 is transmitted to a movement detection roller 13, and the movement detector 3 detects the movement of the apparatus in the scanning direction by the rotation of the movement detection roller 13. On the other hand, when the device is moved straight on the curved surface to be measured 100 shown in FIGS. 4A to 4C in the direction of the scanning line 200 by the rotation of the wheels 5, the interval of Δx becomes the interval between the support legs. L ₁ −L ₂ , L ₂ −L ₃ so that “Δx << L” is significantly smaller than L.
..., the distance L connecting the two support legs 9, 9
Are, as shown in FIG. 4A, the line segments L ₁ -L ₁ ′, L ₂ −
_{L 2 '......, Ln-Ln} ' becomes.

The rotation of the wheel 5 causes the scanning line 200 to move.
4B, the distance line L ₂ -L ₂ ′ connecting the two support legs 9, 9 has three inflection points as shown in FIG. If the distances (measurement pitches) are set to L ₁ −L ₂ , L ₂ −L ₃ . Also when is straight in the 200-direction scanning line by the rotation of the wheel 5, a line segment as shown in FIG. 4 (C) L ₂
When −L ₂ ′ is translated, correct measurement cannot be performed even when the change tendency between the measured data and the inclination θ does not match as indicated by the one-dot chain line. Therefore, also in this case, if the interval of Δx is set to L ₁ −L ₂ , L ₂ −L ₃ ... So that “Δx << L” is significantly smaller than the interval L of the support legs, the inflection point is one or less. Becomes a smooth curve.

Then, all the line segments L₁-L₁’,…
.., Ln-Ln ′ are points on the scanning line of the surface 100 to be measured.
Therefore, the interval Δx (measurement pitch) L₁−
L_Two, L 2-L_Three… For all line segments
If tied to satisfy
It is infinitely approximated to a shape on 100 scanning lines. Theory again
As will be described, the interval (measurement pitch) L of the line segment Δx is₁−
L_Two, L_Two-L_Three... means that two or more inflection points on the surface 100 to be measured
Take small so that there is no upper straddle. That is, sufficient measurement pitch
If it is small, the line segment L₁-L_Two, L_Two-L_Three...
The shape of the surface to be measured, where the connecting line curve has no more than one inflection point
Can be sufficiently approximated.

In this case, the line segments L ₁ -L ₂ , L ₂ -L ₃ ...
The measurement points (measurement pitches) are set for each unit of the movement amount by the movement amount detection roller 13, and the angle detectors 10A of the gyro 1 with two degrees of freedom for each measurement pitch are provided.
The inclination angle θ of the surface to be measured 100 in the scanning direction is obtained based on the detection signals of the roll angle and the pitch angle from 10B. Therefore, according to the present embodiment, the measurement pitches L ₁ -L ₂ , L _2-
L ₃ ... Only the inclination angle θ can be sequentially obtained, and the position of each measurement pitch cannot be obtained. However, if the following two conditions are satisfied, the position of each measurement pitch is related to another line segment. Can be determined from 1) An approximation curve connecting arbitrary n points has one inflection point in that section.
Less than (no more than two). (Not as shown in FIG. 4 (B)) 2) In any section of the obtained approximated curve, the corresponding measured data and the inclination θ change in the same tendency. ((C) in FIG. 4)
Not to be like)

Therefore, as described above, the apparatus is connected to the scanning line 2.
00, and the roll angle and pitch angle detection signals from the angle detectors 10A and 10B of the two-axis gyro 1 are input to the computer 4, and based on these signals, the inclination of the surface to be measured 100 in the scanning direction. The angle θ is calculated and the flatness Z of the surface to be measured 100 and the like are calculated as shown in the above equation.

In the computer 4, the calculated value of the inclination angle θ in the scanning direction of each measuring point based on the detection signals of the roll angle and the pitch angle and the device (main unit 2) input from the movement amount detector 3 Based on the detected value of the movement amount, the amount of unevenness, that is, the flatness Z, at each measurement point in the scanning line 200 direction is calculated by the above equation (Equation 3). Calculated surface 1 to be measured
The flatness of each measurement point in the scanning direction of 00 is displayed on the display device 19 and printed out as necessary.

As described above, according to the embodiment of the present invention, since the tilt angle of the surface to be measured is measured by the gyro 1 having two degrees of freedom, the occurrence of an error due to the uneven scanning speed of the apparatus can be avoided. Thereby, high measurement accuracy can be obtained even for high-speed scanning.

[0033]

As described above, according to the present invention, the inclination angle of the surface to be measured can be measured by the pitch angle and the roller angle from the gyro, and the occurrence of errors due to uneven scanning speed of the main body can be avoided. High measurement accuracy can be obtained for scanning, and the flatness of large parts such as can parts for large diesel engines can be measured automatically and with high accuracy.

Therefore, according to the present invention, the inclination angle of each part of the surface to be measured using the gyro is detected, and the flatness of the surface to be measured is calculated based on the detected data. However, the flatness can be measured easily and with high accuracy without requiring a lot of man-hours and skill.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a flatness measuring device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part of the embodiment.

FIG. 3 is a view as viewed in the direction of the arrow Z in FIG. 2;

FIG. 4 is an operation explanatory view of the embodiment.

FIG. 5 is a perspective view showing a flatness measuring method according to the related art.

FIGS. 6A and 6B are graphs showing the principle of measurement. FIG. 6A shows the principle of obtaining the flatness Z of the surface to be measured when the scanning (measurement) direction is set to the X axis, and FIG. Indicate the measurement pitch not more than one.

[Explanation of symbols]

 Reference Signs List 1 gyro 2 degrees of freedom gyro 2 main body 3 movement amount detector 4 computer 5 wheels 9 support leg 10 angle detector 11 roll angle detection frame 12 pitch angle detection frame 13 movement amount detection roller 14 axle 19 display device 100 measured surface 200 Scan line

Claims (2)

[Claims] 1. A flatness measuring device which scans a surface to be measured and measures the flatness of the surface to be measured, comprising: a wheel moving along the scanning line; and a wheel contacting two points on the scanning line. A gyro attached to the main body, the gyro being attached to the main body, and detecting a tilt angle of a straight line segment between the support legs at each portion in the scanning direction; and detection data of the tilt angle from the gyro And a computer that calculates the flatness of the surface to be measured based on the detection data of the tilt angle at each part in the scanning direction. 2. A moving amount detector for detecting a moving amount of the main body in a scanning direction of the surface to be measured, and wherein the computer detects the moving amount in addition to tilt angle detection data from the gyro. 2. The flatness measuring device according to claim 1, wherein the flatness measuring device is configured to measure the flatness of the surface to be measured based on detection data of the amount of movement of the main body from the container.