JPH04320920A - Method and apparatus for measuring average diameter of roundness measuring instrument - Google Patents

Abstract

PURPOSE:To enable accurate measurement of the average diameter of a substance to be measured without increasing the cost for equipment, by determining offset amounts of a reference diameter and first and second reference radiuses at prescribed measuring positions of the substance to be measured. CONSTITUTION:A reference diameter at a prescribed measuring position of a substance 26 to be measured is measured by a diameter measuring means 41, while a first reference radius at a prescribed measuring position of the substance 26 and a second reference radius at a measuring position spaced by 180 deg. from a prescribed measuring range are measured by a detector 28, and an offset amount of the substance to be measured is calculated on the basis of the reference diameter and the first and second reference radiuses. Next, radiuses at arbitrary measuring positions of the substance 26 which are set at a plurality of places are measured by the detector 28 and also radiuses at measuring positions spaced by 180 deg. from the arbitrary measuring positions are measured. Then, the offset amount, the radiuses at the arbitrary measuring positions and the radiuses at the measuring positions spaced by 180 deg. from the arbitrary measuring positions are subjected to computation 36 on the basis of a formula inputted 38 beforehand and the respective diametric dimensions at the arbitrary measuring positions are calculated, whereby the average diameter of the substance 28 to be measured is calculated.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method for measuring the average diameter of a roundness measuring machine and an apparatus therefor, and more particularly to a method for measuring the average diameter of a roundness measuring machine for measuring the average diameter of the inner diameter or outer diameter of an object to be measured. and related to equipment.

0002

2. Description of the Related Art Generally, when a ring or the like is fitted into a shaft or a hole, settings are made so that the ring and the shaft or the ring and the hole are properly fitted. On the other hand, if the wall thickness of the ring is thin, it is difficult to process the ring with high accuracy. Therefore, since the processed ring is not a perfect circle but has a complicated shape, it is difficult to accurately measure the average diameter of the processed ring. However, when fitting this ring into a shaft or hole, it is important to know the fitting condition of the ring and shaft or ring and hole, and for this purpose, it is necessary to accurately measure the average diameter of the ring. It is essential.

[0003]The following three methods are used to measure the average diameter.
Two methods are known. The first method is to measure the outer diameter and inner diameter of the object to be measured at several locations with a micrometer, caliper, etc., and then take the average value of the measured values as the average diameter. FIG. 4 explains the case where the inner diameter of the ring 2 is measured by the first method. The second method is to simultaneously measure the inner diameter (mainly) of the object to be measured in three or four directions using an air micrometer or the like, and to obtain the average diameter in the three or four directions. FIG. 5 illustrates a case in which the outer diameter of the shaft 4 is measured by the second method, and FIG. 6 illustrates a case in which the inner diameter of the ring 6 is measured by the second method.

Furthermore, the third method is to read the amount of movement of the detector of the roundness measuring machine on a digital scale, calculate the signal of the detector and the amount of movement, and obtain the average diameter of the object to be measured. .

[0005]

[Problems to be Solved by the Invention] However, in the first method and the second method, when the object to be measured has a complex shape rather than a perfect circle like the thin ring mentioned above, the average There is a problem in that it is difficult to accurately measure the diameter. In addition, the third method requires a high-precision roundness mechanism, a mechanism to move the detector parallel to the rotation axis, and a digital scale to detect the amount of radial movement of the detector, which increases the cost of equipment. Furthermore, there is a problem in that the detector signal fluctuates due to ambient conditions such as heat, making it difficult to accurately measure the average diameter of the object to be measured.

The present invention has been made in view of the above circumstances, and provides an average diameter measuring machine that can accurately measure the average diameter of an object to be measured without increasing the cost of equipment. The purpose is to propose measurement methods and devices.

[0007]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention has a method of placing an object to be measured on a table provided in the main body, bringing the tip of a detector into contact with the object, and then placing the object on the table. Or, in a method for measuring the average diameter of a roundness measuring machine that measures the roundness of a workpiece based on the displacement of a tip by rotating a detector, the reference diameter at a predetermined measurement position of the workpiece is determined. a first reference radius at a predetermined measurement position of the object to be measured and a second reference radius at a measurement position spaced 180° from the predetermined measurement position with the detector; 1. Calculate the offset amount of the object to be measured from the second reference radius and the reference diameter, set a plurality of arbitrary measurement positions of the object to be measured, and use the detector to calculate the radius of the arbitrary measurement position of the object to be measured. The radius of the measurement position spaced 180° from the measurement position is measured, and the radius of the measurement position spaced 180° from the measurement position is calculated from the offset amount, the radius of the arbitrary measurement position, and the radius of the measurement position spaced 180° from the measurement position. The present invention is characterized in that each diameter dimension is calculated, and the average diameter of the object to be measured is calculated from each diameter dimension.

[0008]

[Operation] According to the present invention, the diameter measuring means measures the reference diameter at a predetermined measurement position of the object to be measured, and the detector further measures the first reference radius at the predetermined measurement position of the object to be measured and the reference diameter from the predetermined measurement position. The calculation unit measures the second reference radii at measurement positions spaced apart by 180°, and calculates the offset amount of the object based on the reference diameter, first and second reference radii inputted into the programming means in advance. Calculate the offset amount of the object to be measured. Next, measure the radius of an arbitrary measurement position of the object to be measured, which is set at multiple locations, with a detector, and also measure the radius of measurement positions 180° apart from the arbitrary measurement position, and calculate the offset amount and the radius of the arbitrary measurement position. and 180 from the measurement position
The diameter of each arbitrary measurement position is calculated by calculating the radius of measurement positions at intervals in the calculation unit based on the formula inputted into the programming means in advance, and the diameter of each measurement position is calculated from each diameter. The average diameter can be calculated.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the method and apparatus for measuring the average diameter of the roundness measuring machine according to the present invention will be described in detail below with reference to the accompanying drawings. In FIG. 1, the table 12 of the roundness measuring machine 10
is rotatably provided on the main body 14. A motor 20 is connected to the table 12 via a bearing 16 and an encoder 18.
are connected, and the table 12 rotates when the motor 20 is driven. Furthermore, the table 12 has an X-axis knob 22 and a Y-axis knob 22.
An axis knob 24 is provided, and when the X-axis knob 22 is operated, the table 12 moves in the X-axis direction, and when the Y-axis knob 24 is operated, the table 12 moves in the Y-axis direction.

Further, an object to be measured 26 is placed on the table 12, and a tip 3 of a detector 28 is mounted on the object to be measured 26.
0 is in contact. The detector 28 sends the displacement signal of the tip 30 to a calculation unit 36 via an amplifier 32 and an A/D converter 34.
Enter. In addition, the arithmetic unit 36 includes the encoder 1 described above.
A rotation angle signal of the table 12 is input from 8, and information to be described later is input from a program section 38. Furthermore, a predetermined measurement position of the object to be measured 26 and a reference diameter D measured at the predetermined measurement position using a diameter measuring means 41 (see FIG. 2) such as a micrometer or a caliper are input to the calculation unit 36 via an input means 40. Ru.

The control unit 42 controls the drive of the motor 20 based on the signal output from the calculation unit 36, and the display unit 44 and printer 46 display the values calculated by the calculation unit 36. The average diameter measuring device 48 of the roundness measuring machine is comprised of the above-mentioned encoder 18, arithmetic section 36, program section 38, control section 42, and the like. The operation of the average diameter measuring device of the roundness measuring machine constructed as described above will be explained based on the plan view of FIG. 2 and the flowchart of FIG. 3.

First, the object to be measured 26 is placed on the table 12. Then, the reference diameter of the object to be measured 26 is measured with a diameter measuring means 41 such as a micrometer or a caliper, and the measured reference diameter D and the measured angle (i.e., the measurement of the object to be measured 26 with respect to the reference position of the table 12) are determined. The operator inputs the angle β) of the location into the calculation unit 36 via the input means 40 (step 50).

Next, the tip 30 of the detector 28 is connected to the object to be measured 2.
6, the table is rotated, and the tip 30 measures the first reference radius R (β) and the second reference radius R (β + π) at the measurement positions (β) and (β + π), respectively. The first
The values of the reference radius R(β) and the second reference radius R(β+π) are input to the calculation unit 36 via the amplifier 32 and A/D converter 34 (step 52).

The first and second reference radii R(β) are stored in the calculating section 36.
When the values of R(β+π) and
=D-{R(β)+R(β+π)} (d: amount by which the center of the object to be measured 26 is offset from the rotation center of the X-Y table 12) Find the offset amount d (step 54).

Next, with the tip 30 of the detector 28 in contact with the object to be measured 26, the table is rotated to remove the tip 30 of the detector 28.
The measurement position θn of the object to be measured 26 is preset as 0.
(n=1, 2, 3...) radii R(θn) and R(θn
+π) is determined (step 56). Radius R(θn
) and R(θn +π), these values are input into the program section 38 in advance.

Dn = R (θn ) + R (θn + π) + d (θ
Dn (n=1, 2,
3...) is determined (step 58). The required Dn (
n=1, 2, 3...) is each measurement position θn (n=1, 2,
3...), the average circle D' of the object to be measured 26 is expressed by the formula D'=(D1 +D2 +D3...)/n, and this formula is input into the program section 38 in advance. Therefore, when Dn (n=1, 2, 3, . . . ) is determined in step 58, the average circle D' of the object to be measured 26 is determined (step 60).

The determined value of the average circle D' of the object to be measured 26 is displayed on the display section 44 or the printer 46 (step 62). In the embodiment described above, the average measuring method and device for a roundness measuring machine in which the table 12 rotates have been described, but the present invention is not limited thereto and can be applied to a device in which the detector 28 is rotated.

[0018]

As explained above, according to the method and apparatus for measuring the average diameter of a roundness measuring machine according to the present invention, each radius of the reference diameter and the reference diameter at a predetermined measurement position of the object to be measured, that is, the first , and the second reference radius based on the formula for calculating the offset amount to calculate the offset amount of the object to be measured, and then from the radius of the arbitrary measurement position of the object to be measured set at multiple locations and the arbitrary measurement position. The average diameter of the object to be measured can be calculated by calculating the radii of measurement positions separated by 180 degrees and the obtained offset amount based on an average diameter calculation formula.

Therefore, it is possible to accurately measure the average diameter of the object to be measured even if the roundness measuring machine does not have a digital scale for detecting the amount of movement of the detector from the rotational axis and a mechanism for accurate parallel movement. Therefore, it is possible to prevent an increase in equipment costs.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an average diameter measuring device of a roundness measuring machine according to the present invention.

FIG. 2 is an explanatory diagram of a method for measuring an average diameter.

FIG. 3 is a flowchart of a method for measuring an average diameter.

FIG. 4 is a schematic diagram of a conventional average diameter measuring device.

FIG. 5 is a schematic diagram of a conventional average diameter measuring device.

FIG. 6 is a schematic diagram of a conventional average diameter measuring device.

[Explanation of symbols]

10... Roundness measuring machine 12...table 14...Main body 18...Encoder 26...Object to be measured 28...Detector 30...Tip 36... Arithmetic unit 38...Program means 41...Diameter measuring means 48... Average diameter measuring device

Claims (2)

[Claims] Claim 1: The object to be measured is placed on a table provided in the main body, the tip of the detector is brought into contact with the object to be measured, and the table or the detector is rotated to measure the object to be measured based on the displacement of the tip. In an average diameter measuring method of a roundness measuring machine for measuring the roundness of an object, a reference diameter at a predetermined measurement position of the object to be measured is measured by a diameter measuring means, and the diameter of the object to be measured is measured by the detector. A first reference radius at a predetermined measurement position and a second reference radius at a measurement position spaced 180° from the predetermined measurement position are measured, and a diameter of the object to be measured is determined from the first and second reference radii and the reference diameter. Calculate the offset amount, set a plurality of arbitrary measurement positions on the object to be measured, and use the detector to calculate the radius of the arbitrary measurement position on the object to be measured and the radius of the measurement position spaced 180 degrees from the measurement position. and calculate the diameter dimension of each arbitrary measurement position from the offset amount, the radius of the arbitrary measurement position, and the radius of the measurement position spaced 180 degrees from the measurement position, and A method for measuring an average diameter using a roundness measuring machine, characterized by calculating an average diameter of an object to be measured. 2. Place the object to be measured on a table provided in the main body, bring the tip of the detector into contact with the object, and rotate the table or detector to measure the object based on the displacement of the tip. An average diameter measuring device of a roundness measuring machine for measuring the roundness of a workpiece includes a diameter measuring means for measuring the diameter of the workpiece, and a detector for measuring a predetermined measurement position of the workpiece. and the first reference radius determined by 180° from the measurement position.
The diameter of the object to be measured is determined from the second reference radius obtained by measuring the measurement positions at intervals, and the reference diameter obtained by measuring the measurement positions of the first and second reference radii with the diameter measuring means. Calculate an offset amount, and calculate each diameter from the offset amount, the radius of a plurality of arbitrary measurement positions of the object to be measured measured by the detector, and the radius of measurement positions spaced 180° from the measurement position. a program means into which a formula for calculating the average diameter of the object to be measured is inputted from each of the diameters; means for detecting the rotation angle of the table or the detector and outputting a detection signal; A calculation unit to which the radius dimension of the object to be measured is inputted via the tip when the instrument is rotated, and the rotation angle signal of the table or detector outputted from the detection means is inputted, the rotation angle signal being inputted. The first and second reference radii and reference diameter when is at the predetermined measurement position, the radius when the rotation angle signal is at an arbitrary measurement position, and the radius at a position 180° apart from the arbitrary measurement position, An average diameter measuring device for a roundness measuring machine, characterized by comprising: a calculation unit that calculates the average diameter of the object to be measured by calculating the average diameter of the object to be measured by calculating the average diameter of the object to be measured using the formula inputted into the program means; .