JPH0654204B2 - Sphere size measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a sphere size for performing shape measurement such as measurement of diameter, sphericity and surface roughness of a sphere such as a bearing ball. The present invention relates to a measuring device, and more particularly, to a sphere size measuring device capable of quickly and highly accurately setting a sphere to be measured at a fixed position on a surface plate and significantly shortening a measurement work time.

(Prior Art) As a rolling bearing that supports a shaft that rotates at high speed, a bearing in which a large number of spheres are mounted on the inner circumference of a housing is used in many devices. Since the shape of the bearing sphere determines the function and life of the bearing, the dimensions and shape of the sphere such as diameter, sphericity and surface roughness are measured in the manufacturing process, and the measured value may be within the allowable value. It is confirmed. JIS for specific measurement methods and allowable values
(B-1501-1953) and the like.

Conventionally, for example, when measuring the diameter of a sphere, generally,
A sphere size measuring device 1 as shown in the figure was used.

This spherical body size measuring device 1 includes a support column 3 protruding from a base 2.
A measurement head 4 mounted on the measurement head 4 such that it can be raised and lowered and horizontally rotated, a probe 5 mounted on the tip of the measurement head 4, for example, an electric micrometer, and arranged to face the probe 5. The base plate 6 has a reference surface finished with high precision and smoothness, and a sphere holder 7 slidably disposed on the upper surface of the base plate 6. The sphere holder 7 is formed with a V-shaped groove 9 for holding the sphere 8 to be inspected on the surface plate 6 and holding it at a fixed position. After guiding the sphere 8 to the fixed position, sphere holding A fixing screw 10 for fixing the tool 7 is provided.

The electric micrometer used as the probe 5 usually has a measurement accuracy of about 1 μm, although it depends on the dimensional accuracy required for the sphere 8 to be measured.

When measuring the diameter of the sphere 8 to be inspected using the sphere size measuring device 1 having the above-mentioned configuration, first the sphere 8 to be inspected is placed on the surface plate 6, and the upper surface of the surface plate 6 and the sphere holder 7 are placed. The spherical body 8 to be inspected is sandwiched by the three planes formed by the V-shaped groove 9 and. Slide the sphere holder 7 in the horizontal direction while sandwiching it,
The position is finely adjusted so that the apex of the sphere 8 to be measured coincides with the position of the tip of the pointer of the probe 5.

That is, with the sphere 8 to be inspected pressed against and brought into contact with the three planes, the sphere holder 7 is manually finely moved along the upper surface of the surface plate 6 and fixed at a position where the reading of the probe 5 is maximized. The sphere holder 7 is fixed to the surface plate 6 by tightening the manual screw 10, and the so-called peaking is completed. By this fixing work, preparation for measuring the diameter of the sphere 8 to be inspected is completed.

Thereafter, the test spheres 8 having the same diameter are fixed 3
By pressing on a flat surface, it becomes possible to set the apex, and the diameter can be continuously measured. After that,
Perform calibration using the masters and gauges required for dimension measurement and then move to measurement work.

That is, while maintaining the state in which the vertex position of the test sphere is fixed, the test sphere 8 is rotated, the measurement direction is changed several tens of times, and the diameter of each direction is measured by the probe 5. The diameter is measured with an accuracy of the order of 1/10 / to 1/100 μm, and the average diameter and diameter disparity are calculated by aggregating the measured values, and whether the calculated value is within the allowable limit is acceptable. Is determined.

(Problems to be Solved by the Invention) However, according to the conventional sphere size measuring apparatus 1, the work of finely adjusting the position of the sphere holder is carried out manually by the inspector.

By the way, spheres used for bearings (balls)
In order to measure the dimension of 1 with an accuracy of the order of 1/100 μm to 1/10 μm, it is necessary to fix the sphere holder on the surface plate with a positional accuracy of several tens of μm. As the diameter of the sphere becomes smaller, the sphere holding becomes smaller. The positional accuracy of the tools will be sharply sharpened. For example, a sphere having a diameter of 3/8 inch (φ9.525 mm) requires a positioning accuracy of about ± 30 μm, and a sphere having a diameter of 1 mm requires a positioning accuracy of about ± 10 μm.

In addition, since the sphere has a shape in which the dimensions change three-dimensionally continuously, when performing the so-called apex determination to determine the top position of the sphere, at least two planes (X A complicated operation is required to perform positioning by pushing in from the (axis, Y axis) direction.

On the other hand, in recent years, the miniaturization and integration of the equipment have been advanced, and the spheres that are the component parts thereof are required to be minute and highly accurate.

However, when measuring the size of a small sphere, it is very difficult to manually perform fine adjustment of the sphere to a predetermined position with an accuracy of several tens of μm. Performing it manually requires a high level of skill and requires a long inspection time, resulting in an increase in the number of inspection steps. By the way, when measuring the size of a small sphere with a diameter of 1 to 2 mm, the time required to adjust the position of the sphere holder may reach more than half of the total inspection time required to complete the size measurement, and it is remarkably inspected. There was a problem that the efficiency was lowered.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to fix the sphere to be inspected on the surface plate with high accuracy and speed, and to reduce the inspection work time significantly. An object is to provide a measuring device.

(Structure of the Invention) (Means for Solving the Problems) In order to achieve the above object, a sphere size measuring device according to the present invention is a measuring element for contacting a sphere and measuring the size of the sphere, and a horizontal surface facing the measuring element. The X-axis is configured to be movable in two axis (XY) directions that are orthogonal to each other on a horizontal plane while providing a measuring device main body having a surface plate on which a sphere is placed.
-An XY coordinate measuring device that has a Y table and measures the coordinates after movement with a dimensional accuracy of 0.01 mm or less is attached to the measuring device body, and the sphere is guided to a predetermined position on the surface plate. The spherical holder for holding and fixing
It is characterized by being integrally attached to the Y table.

Further, the surface plate, the sphere holder, and the tracing stylus may be formed of a ceramic sintered body.

(Operation) According to the sphere size measuring device having the above-described configuration, since the sphere holder for holding the sphere to be tested is integrally mounted on the XY table of the XY coordinate measuring device, at least 10 μm.
It is possible to fix the sphere holder at a predetermined position on the surface plate with high position accuracy on the order of m. That is, by numerically inputting the movement amount in the X-axis direction or the Y-axis direction to the XY coordinate measuring device, the XY table is quickly moved in the designated direction, and is integrated in the XY table. It is possible to quickly move the mounted sphere holder to the apex position of the sphere.

Therefore, it becomes possible to carry out the vertex setting operation with extremely high precision, easily and quickly, and the measurement work time is greatly shortened.

In addition, the surface plate, sphere holder, and probe are made of a ceramic sintered body, which increases wear resistance and corrosion resistance compared to conventional metal ones, and also has a small coefficient of thermal expansion and is lightweight. Since the rigidity can be increased while improving the measurement accuracy, the measurement accuracy can be improved, and the measurement accuracy can be maintained for a long time, and the reliability of the inspection can be significantly improved.

(Embodiment) Next, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing an embodiment of a sphere size measuring apparatus according to the present invention. The same elements as those of the conventional apparatus shown in FIG. 2 are designated by the same reference numerals and detailed description thereof will be omitted.

The sphere size measuring device 11 according to the present embodiment has an electric micrometer as a measuring element 5 that abuts on the sphere 8 to be measured and measures the size of the sphere, and the sphere 8 to be measured on a horizontal plane facing the sphere 5. Measuring device main body 12 equipped with a surface plate 6 for mounting a table
On the other hand, an XY table 13 is provided which is movable in two axis (XY) directions orthogonal to each other on a horizontal plane, and the coordinate after the movement is measured with a dimensional accuracy of 0.001 mm. A Y-coordinate measuring device 14 is attached to the measuring device main body 12, and a sphere holder 15 for guiding and holding and fixing the sphere 8 to be inspected to a predetermined position on the surface plate 6 is attached to the X-axis.
The Y table 13 is integrally mounted and configured.

The surface plate 6, the sphere holder 15, and the tracing stylus 5 are made of a ceramic sintered body.

Here, the XY coordinate measuring device 14 is generally commercially available as position control equipment, and is placed on the upper part of the main body so that the XY table 13 is biaxial (X axis,
It has a built-in servo mechanism that moves in the (Y-axis) direction.
It is configured to be movable in each axial direction with a positional accuracy of μm.

The movement distance in each direction is the digital display window 16X, 16
Displayed numerically by Y. In addition, the adjustment handle 18 mounted on each micrometer head 17X, 17Y
X and 18Y can also be rotated in each direction by rotating it manually.
The Y table 13 is constructed so that it can be moved with a very small size.

The dimensional measurement accuracy of the XY coordinate measuring device 14 is at least 0.
If it is 01 mm, it is possible to easily and quickly position even a microsphere having a diameter of about 1 mm and with high accuracy, but it is desirable to use one having an accuracy of about 0.001 mm as in this embodiment. .

When measuring the size of a sphere using the sphere size measuring device 11 according to the present embodiment, first, the sphere to be inspected is formed on the three planes formed by the surface plate 6 and the V-shaped groove 9 of the sphere holder 15. 8 is pressed, and the tip of the electric micrometer as the probe 5 is brought into contact with the surface of the sphere 8 to be inspected.

Next, the XY table 13 is moved by a small distance in the X-axis or Y-axis direction so that the apex of the test sphere 8 coincides with the tip of the probe 5. This moving operation is preferably performed automatically by a servo mechanism controlled by a numerical value (5 to 15 μm) of a previously input moving distance, but by manually rotating the adjusting handles 18X and 18Y by a predetermined angle. Can also be performed.

In this way, the XY table 13 is slightly moved in the X-axis and Y-axis directions, and the position at which the reading of the probe 5 is maximized becomes the fixed position. After that, the diameter in each direction of the sphere to be measured is sequentially measured in the usual manner.

According to the apparatus of this embodiment, the sphere holder 15 is integrally mounted on the XY table 13 capable of controlling the moving distance with high accuracy and speed, so that the sphere 8 to be inspected on the surface plate 6 is fixed. It is possible to carry out the peak-setting work extremely quickly and with high accuracy, and as a result, the inspection and measurement work time is significantly shortened, and the measurement accuracy can be further improved.

Next, the difference in effect when the diameter of a minute sphere is actually measured using the device of the present invention and the conventional device will be described more specifically.

A high-precision standard sphere having a diameter accuracy of ± 0.03 μm with a diameter of 1.5 mm is used as the sphere to be inspected 8 by using the device of the present invention and the conventional device to repeat the peak-extracting work and the diameter-measuring work 10 times, and fluctuations in the measured values When the total inspection time including the width and the working time for peaking was measured, the values shown in Table 1 below were obtained.

As is clear from the results of Table 1, according to the apparatus of the present embodiment, the positioning operation of the sphere 8 to be inspected by the sphere holder 15 can be performed with high accuracy and speed, so that the total inspection time is 1
It is shortened to / 3 to 1/4.

Therefore, no high skill is required for the inspection and measurement work, and the efficiency and reliability of the inspection and measurement work can be significantly improved.

By the way, the reference surface of the surface plate 6, the sphere holder 15, and the tip of the probe 5 are constantly in contact with the sphere 8 to be inspected having high hardness. There is a high possibility that the measurement accuracy is lowered due to the influence of the thermal expansion due to.

As a countermeasure against this, by constructing the components such as the platen 6 with a ceramic sintered body, the wear resistance and the corrosion resistance are improved and the coefficient of thermal expansion is reduced as compared with the conventional metal products. In addition, the rigidity can be increased while further reducing the weight.

Therefore, the measurement accuracy can be improved and the reliability of the inspection can be maintained for a long time.

(Effects of the Invention) As described above, according to the sphere size measuring apparatus of the present invention, the sphere holder for holding the sphere to be tested is integrally mounted on the XY table of the XY coordinate measuring apparatus. Because
It is possible to fix the sphere holder at a predetermined position on the surface plate with high positional accuracy of at least 10 μm order. That is, by numerically inputting the movement amount in the X-axis direction or the Y-axis direction to the XY coordinate measuring device, the XY table is quickly moved in the designated direction, and is integrated in the XY table. It is possible to quickly move the mounted sphere holder to the apex position of the sphere.

Therefore, it becomes possible to carry out the vertex setting operation with extremely high precision, easily and quickly, and the measurement work time is greatly shortened.

Further, by constructing the surface plate, the sphere holder and the measuring element with a sintered body of ceramics, the wear resistance and the corrosion resistance are higher than those of the conventional metal, and the coefficient of thermal expansion is small, and Since the rigidity can be increased while reducing the weight, the measurement accuracy can be improved, and the measurement accuracy can be maintained for a long time, and the reliability of the inspection can be significantly improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a sphere size measuring apparatus according to the present invention, and FIG. 2 is a perspective view showing a configuration example of a conventional apparatus. 1 ... Sphere size measuring device, 2 ... Base, 3 ... Post, 4
…… Measuring head, 5 …… Sensor, 6 …… Surface plate, 7 …… Sphere holder, 8 …… Inspected sphere, 9 …… V-shaped groove, 10 ……
Fixing screw, 11 ... Sphere size measuring device, 12 ... Measuring device main body, 13 ... XY table, 14 ... XY coordinate measuring device, 15 ... Sphere holder, 16X, 16Y.
Digital display window, 17X, 17Y ... Micrometer head, 18X, 18Y ... Adjustment handle.

Claims (2)

[Claims] 1. A measuring device main body is provided which is provided with a stylus for abutting against a sphere to measure the size of the sphere and a surface plate for mounting the sphere on a horizontal plane facing the stylus, while being orthogonal to each other on the horizontal plane. The XY coordinate measuring device having an XY table configured to be movable in two axis (XY) directions and measuring coordinates after movement with a dimensional accuracy of 0.01 mm or less is measured. A sphere size measuring device characterized in that a sphere holder, which is attached to the main body of the device and guides and holds the sphere to a predetermined position on a surface plate, is integrally mounted on the XY table. 2. The sphere size measuring device according to claim 1, wherein the surface plate, the sphere holder and the measuring element are formed of a ceramic sintered body.