JP2020160091A - Linear expansion coefficient measurement method and measurement apparatus for dimension reference device - Google Patents

Abstract

To provide a linear expansion coefficient measurement method and measurement apparatus for a dimension reference device capable of highly accurately and inexpensively measuring a linear expansion coefficient for dimension reference devices of various lengths.SOLUTION: By using a measurement target first support base 51, a measurement target second support base 52, a reference gauge first support base 61, and a reference gauge second support base 62, a measurement object (10) and a reference gauge (20) are supported in parallel the inside of a constant temperature bath 30. A linear expansion coefficient measurement method includes the steps of: comparatively measuring a length from a first surface 11 to a second surface 12 of the measurement object by setting an internal temperature of the constant temperature bath 30 at a first temperature and defining, as a reference, a length from a first reference surface 21 to a second reference surface 22 of the reference gauge; comparatively measuring a length from the first surface 11 to the second surface 12 by setting the internal temperature of the constant temperature bath 30 at a second temperature and defining, as a reference, a length from the first reference surface 21 to the second reference surface 22; and calculating a linear expansion coefficient of the measurement object from the length of the measurement object at the first temperature and the length of the measurement object at the second temperature.SELECTED DRAWING: Figure 4

Description

The present invention relates to a method for measuring the coefficient of linear expansion of a dimensional reference device and a measuring device.

In a measuring device such as a coordinate measuring machine, a dimensional reference device is used for inspection.
As the dimensional reference device, various block gauges whose end face dimensions are calibrated with high accuracy are used, and step gauges corresponding to a plurality of lengths are used.
The step gauge has a comb-teeth shape in which convex portions and concave portions are alternately arranged, and a plurality of reference dimensions can be obtained between the end faces of the convex portions. Such a step gauge is manufactured by alternately arranging a measuring block as a convex portion and an interval block as a concave portion and fixing them to a holder, or by shaving from a single member in a comb-teeth shape. Manufactured.

The calibration value of the distance between the end faces of the step gauge is provided as a length at a specific temperature, often the length at 20 ° C., an industrial standard temperature.
In the inspection of the coordinate measuring machine, it is necessary to convert the measured length into the temperature at the time of calibration and use it. This is generally called length temperature compensation. At this time, it is necessary to know the coefficient of linear expansion of the step gauge accurately.

Many dimensional standards, including step gauges, have a coefficient of linear expansion used for temperature correction on the calibration certificate or inspection report. Each such coefficient of linear expansion is displayed with a tolerance.
When a step gauge is used for inspection of a CMM, this tolerance is treated as a factor of uncertainty in examining the uncertainty of inspection. Therefore, in order to reduce uncertainty in inspection, it is required to evaluate the coefficient of linear expansion of the step gauge with high accuracy.

The coefficient of linear expansion of an object, including a dimensional reference device, is obtained by changing the temperature of the object and measuring the amount of change in the length of the object due to the temperature change.
Specifically, the coefficient of linear expansion α is Lo for the length of the object at the reference temperature To, L for the length of the object at the current temperature T, the amount of temperature change ΔT = T-To, and the amount of change in length (thermal expansion). Amount) ΔL = L−Lo, which is given by α = (ΔL / L) · (1 / ΔT).

In a dimension reference device such as a step gauge, the size of the length L of an object is larger than 10 5 with respect to the amount of change ΔL of the length. Therefore, in general, the accuracy of the numerical value of the length L has a small influence on the numerical value of the coefficient of linear expansion α.
Therefore, in order to obtain the coefficient of linear expansion α with high accuracy, it is necessary to measure the temperature change amount ΔT and the length change amount ΔL with high accuracy.

In order to measure the coefficient of linear expansion α like this, a measurement method using a light wave interferometer has been proposed (see Patent Document 1).
In Patent Document 1, two sets of light wave interferometers facing each other on the same measurement axis are used so that the length between both end faces of an object to be measured such as a block gauge can be measured with high accuracy. Then, the temperature of the object to be measured is changed by the temperature control means, and the length is measured at different temperatures to obtain the amount of thermal expansion due to the temperature change and calculate the coefficient of linear expansion.

However, in the length measurement using such a light wave interferometer, there is a problem that the light wave interferometer is expensive. That is, not only is the light wave interferometer itself expensive, but it is also necessary to calculate the refractive index of air in order to correct the wavelength of the light for measurement, which involves the environment such as temperature, humidity, atmospheric pressure, and carbon dioxide concentration. A measuring machine is also required, and there is a problem that the system as a whole becomes expensive.

Further, in the length measurement using the light wave interferometer, since the reflected light from both end faces of the object to be measured is used, the length to be measured is limited to the length of the measurement target. That is, in a reference device having a comb-shaped measuring surface such as a step gauge, there is a problem that it is difficult to apply to the measurement of the length between the convex portions of the intermediate portion.

To solve such a problem, a method using a coordinate measuring machine (see Patent Document 2) and a method using a pinching portion and a strain gauge (see Patent Document 3) have been proposed.

In the method of Patent Document 2, a step gauge as an object to be measured is placed in a constant temperature bath, a probe of an external coordinate measuring machine is introduced from an opening of the constant temperature bath, and the length of the step gauge is measured by this probe. To do. Then, the temperature setting in the constant temperature bath is changed, the length is measured at different temperatures, and the amount of thermal expansion is calculated from the difference in the measured lengths before and after the temperature change.
In the length measurement using such a three-dimensional measuring machine, it is not necessary to use a light wave interferometer, and an environment in which a general-purpose three-dimensional measuring machine can be used is sufficient.
Further, by using the coordinate measuring machine, the length between the convex portions of the intermediate portion of the step gauge can be measured, and the uniformity of the coefficient of thermal expansion of the intermediate portion can also be measured.

In the method of Patent Document 3, a sandwiching portion that sandwiches an arbitrary convex portion of the step gauge is used, a strain gauge is installed on one of the chips that come into contact with the step gauge of the sandwiching portion, and a pair of end faces for length measurement are sandwiched. The temperature is changed while sandwiched between the parts, and the thermal expansion due to the temperature change is directly detected by the strain gauge.
In the measurement of thermal expansion using such a pinch and a strain gauge, it is not necessary to use a light wave interferometer, and a simple and inexpensive configuration of a pinch and a strain gauge is sufficient, and between the convex portions of the intermediate portion of the step gauge. Length measurement can also be performed.

Japanese Patent No. 3897655 Japanese Unexamined Patent Publication No. 2004-226369 Japanese Unexamined Patent Publication No. 2005-83920

By the way, as a dimensional reference device such as a step gauge, those having various dimensions are used according to the size of the coordinate measuring machine to be inspected. For example, some long step gauges have a nominal size (nominal length) of more than 1.5 m.
It is required that the above-mentioned measurement of the coefficient of linear expansion α of the dimensional reference device can be applied to such a dimensional reference device having a large length L and can be measured with high accuracy.

However, the method of Patent Document 3 described above has a problem that the measurement length is fixed by the sandwiched portion and various measurements such as the length of the intermediate portion cannot be performed. Further, for a long step gauge, it is necessary to prepare a sandwiching portion having an appropriate size, which limits the implementation.
Further, since the output of the strain gauge contains a noise component, there is also a problem that it is difficult to extract only the coefficient of linear expansion of the step gauge from the amount converted into length.

On the other hand, as in Patent Document 2 described above, if a three-dimensional measuring machine is used for length measurement, the length between both end faces and the convex portion of the intermediate portion are obtained with respect to a dimension reference device having various lengths. It is possible to cope with various measurements such as the length between the end faces of, and it is possible to measure the linear expansion coefficient based on the measurements at different temperatures.

However, even when the length measurement by the coordinate measuring machine is used as in the method of Patent Document 2, there is a possibility that the above-mentioned large step gauge having a length exceeding 1.5 m may have a problem such as a decrease in accuracy. ..
That is, the maximum allowable length measurement error is used as an index indicating the measurement performance of the coordinate measuring machine. The maximum permissible length measurement error is generally given by a linear equation and increases in proportion to the measurement length. This means that the accuracy decreases as the length to be measured increases. For this reason, it is difficult to measure the coefficient of linear expansion with high accuracy for a long step gauge.

An object of the present invention is to provide a method and a measuring device for measuring the coefficient of linear expansion of a dimensional standard for various lengths, which can measure the coefficient of linear expansion with high accuracy and at low cost.

In the method for measuring the linear expansion coefficient of the dimension reference device of the present invention, the line of the portion from the first surface to the second surface of the measurement object separated in the stretching direction of the measurement object with the dimension reference device as the measurement object. A method for measuring a linear expansion coefficient of a dimensional reference device for measuring an expansion coefficient, which has a first reference surface and a second reference surface corresponding to the first surface and the second surface, and from the first reference surface. A reference gauge having a known length to the second reference surface, a constant temperature bath capable of accommodating the object to be measured and the reference gauge, adjusting the internal temperature, and having a measurement opening on the measurement surface. A measurement object support base installed inside the constant temperature bath to support the measurement object, a reference gauge support base installed inside the constant temperature bath to support the reference gauge, and the measurement opening. A three-dimensional measuring machine capable of introducing a measuring probe into the constant temperature bath is prepared, and the object to be measured and the reference gauge are supported in parallel inside the constant temperature bath, and the internal temperature of the constant temperature bath is supported. Is the first temperature, and the length from the first surface to the second surface is comparatively measured with the length from the first reference surface to the second reference surface as a reference, and the internal temperature of the constant temperature bath is measured. As the second temperature, the length from the first surface to the second surface is comparatively measured with reference to the length from the first reference surface to the second reference surface, and the first at the first temperature. It is characterized in that the linear expansion coefficient of the object to be measured is calculated from the length from one surface to the second surface and the length from the first surface to the second surface at the second temperature.

In the present invention as described above, since the length of the object to be measured is measured by using a coordinate measuring machine, the linear expansion coefficient of the dimension reference device of various lengths can be increased without using an expensive light wave interferometer. It can be measured accurately.
At this time, the length from the first surface to the second surface can be measured as the length of the object to be measured. Therefore, by setting both end faces of the object to be measured as the first surface and the second surface, the length of the object to be measured and the coefficient of linear expansion between them can be measured. Further, by setting the first surface and the second surface to the end surface of the convex portion of the intermediate portion of the measurement object, the length and the coefficient of linear expansion of the intermediate portion can be measured.

Further, in the present invention, when measuring the length of an object to be measured by using a coordinate measuring machine, a reference gauge is used as a reference for the length, and a comparative measurement of the length with respect to the reference gauge is performed. Therefore, the result of the length measurement does not depend on the accuracy of the scale of the coordinate measuring machine, but depends exclusively on the accuracy of the reference gauge, and high accuracy can be ensured even if the object to be measured becomes long.

That is, in the present invention, in the comparative measurement of length, when the object to be measured is short, a short reference gauge corresponding to the object is used, and when the object to be measured is long, the gauge is correspondingly used. Use a long reference gauge.
Then, the length of the reference gauge (distance between the first reference surface and the second reference surface) and the length of the object to be measured (distance between the first surface and the second surface) are measured by a three-dimensional measuring machine. The difference between the measurement length of the reference gauge and the measurement length of the measurement object is added to the reference length known for the reference gauge, whereby the length of the measurement object is calculated.
That is, in the coordinate measuring machine, the difference between the measurement length of the reference gauge and the measurement length of the object to be measured, specifically, the distance between the first surface and the first reference surface, and the second surface and the second reference surface. It is only necessary to be able to measure the distance between.
Therefore, in the present invention, in the comparative measurement of length, even if the object to be measured is long, it is not affected by the maximum permissible length measurement error which is the measurement performance of the coordinate measuring machine.

Based on the above, according to the method for measuring the coefficient of linear expansion of a dimensional reference device of the present invention, it is possible to measure the coefficient of linear expansion of a dimensional reference device of various lengths with high accuracy and at low cost.

In the method for measuring the coefficient of linear expansion of the dimensional reference device of the present invention, when the comparative measurement is performed, the calculation of the center coordinates of the first reference surface, the second reference surface, the first surface and the second surface is performed. It is desirable to determine the coordinate system including the calculation of the inclination of the reference gauge and the measurement object with respect to the stretching direction.

In the present invention as described above, when performing comparative measurement, it is possible to determine a coordinate system as a reference for measuring the length of each of the reference gauge and the object to be measured.
That is, even if the first reference surface and the second reference surface of the reference gauge and the first surface and the second surface of the object to be measured are inclined with respect to the stretching direction, the contact of the coordinate measuring machine on each surface. The position detected by the coordinate measuring machine can be corrected from the distance from the position to the center coordinates and the inclination of each surface.
Then, each coordinate system is determined according to the current state of the reference gauge and the object to be measured, and the length is measured under the coordinate system to improve the accuracy, and the accuracy of the comparative measurement can be improved. Can be kept high.

In the method for measuring the coefficient of linear expansion of the dimension reference device of the present invention, it is desirable that the reference gauge support base supports the reference gauge on the side of the measurement object facing the measurement opening.
The side facing the measurement opening of the measurement object may be, for example, the upper surface side or the side surface side of the measurement object.

In the present invention as described above, the first surface and the second surface, which are the measurement target parts of the measurement target, are arranged on the measurement opening side, and the reference gauge is arranged on the same side, so that the first reference for comparison is made. The surface and the second reference surface can be arranged close to the first surface and the second surface, and the measurement accuracy can be improved and the efficiency and speed of the measurement operation can be improved.

In the method for measuring the coefficient of linear expansion of the dimension reference device of the present invention, it is desirable that the length of the reference gauge in the stretching direction is shorter than that of the object to be measured.
The predetermined length is such that the surface on the measurement opening side of the object to be measured and the surface closest to the first surface or the second surface can be secured so that the probe of the coordinate measuring machine can come into contact with the surface. It may be the length of. For example, when a step gauge having a plurality of convex portions is used as a measurement object, the reference gauge may be shorter than the length of the step gauge by one convex portion.

In the present invention as described above, since the reference gauge is arranged on the measurement opening side of the measurement object, the surface of the measurement opening side of the measurement object is covered with the reference gauge. However, in the vicinity of the end of the object to be measured, the surface is exposed to the measurement opening side due to the short length of the reference gauge.
Therefore, in the coordinate system determination described above, the surface can be detected without interfering with the reference gauge by bringing the probe of the coordinate system into contact with the exposed surface at the end of the object to be measured.

In the method for measuring the coefficient of linear expansion of the dimensional reference device of the present invention, when the comparative measurement is performed, the first reference surface and the first surface are arranged in the same plane, or the second reference surface and the first surface. It is desirable to arrange the two surfaces in the same plane.

In the present invention as described above, when the reference gauge is shortened by a predetermined length from the object to be measured as described above, the length of the reference gauge and the object to be measured is at the end opposite to the side on the same plane. The difference between the dimensions is maximized, and the margin for surface detection by the probe of the coordinate measuring machine can be maximized.

In the method for measuring the linear expansion coefficient of the dimension reference device of the present invention, the measurement target support base includes the measurement target first support base and the measurement target second support base, and the measurement target first support base and the measurement target first support base. The second support base of the measurement object regulates the displacement of the measurement object in two directions intersecting the stretching direction, and rotates the measuring object around the two directions intersecting the stretching direction. Allowed, either one of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and one of the other is the measurement target in the stretching direction. Allows the displacement of the object, and either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object around the stretching direction and either of them. The other allows the object to be measured to rotate about the stretching direction, and the reference gauge support base includes the reference gauge first support base and the reference gauge second support base, and the reference gauge first support base includes the reference gauge first support base. The support base and the reference gauge second support base each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the rotation of the reference gauge about the two directions intersecting the stretching direction as a central axis. One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and the other one regulates the displacement of the reference gauge in the stretching direction. One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge around the stretching direction, and one of the other supports the stretching direction. It is desirable to allow the reference gauge to rotate about the central axis.

In the present invention as described above, the object to be measured and the reference gauge are allowed to be displaced while the displacement is regulated (positioned) on one of the first and second supports with respect to the displacement in the respective stretching directions. By doing so, it is possible to accurately perform comparative measurement of the length of the object to be measured and the length of the reference gauge in the stretching direction. Further, by restricting the rotation of either the first or second support around the central axis in the stretching direction and allowing the rotation around the other axis, the object to be measured and the reference gauge can be bent. Even if deformation occurs, this can be tolerated.
In the present invention, such a measurement object support and a reference gauge support can cope with free expansion and posture fluctuation of the measurement object and the reference gauge, and the measurement object and the reference gauge can be stretched in different directions. It can be maintained in the desired state parallel to each other.

In the method for measuring the linear expansion coefficient of the dimensional reference device of the present invention, the first support for the object to be measured has a contact portion between a conical hole and a sphere and a contact between a flat surface and the sphere between the bottom surface of the object to be measured. It has one or two of a portion, a V-groove and a contact portion between the sphere, and the measurement object second support has a conical hole and a sphere between the bottom surface of the measurement object and the bottom surface of the measurement object. It is desirable to have a contact portion, a contact portion between the flat surface and the sphere, and a contact portion between the V groove and the sphere, which are not on the first support base of the object to be measured.

In the present invention as described above, the measurement object support including the measurement object 1st support and the measurement object 2 support is a contact portion between the conical hole and the sphere between the measurement object and the bottom surface of the measurement object. A kinematic mount having three points, a contact portion between a flat surface and a sphere and a contact portion between a V groove and a sphere, can be configured, and the above-mentioned displacement regulation and rotation regulation with respect to the extension direction and the intersection direction thereof are appropriately performed. be able to.

In the method for measuring the linear expansion coefficient of the dimensional reference device of the present invention, the first support base of the object to be measured has a contact portion between a conical hole and a sphere and a contact between a flat surface and the sphere between the bottom surface of the object to be measured. The second support base of the object to be measured has one of the portions, and the second support base of the object to be measured has a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the object to be measured. It has a contact portion that is not on the first support of the measurement object, and either the first support of the measurement object or the second support of the measurement object has a contact portion between one side surface of the measurement object and a sphere. It is desirable to have a contact portion and a pressing means for pressing the side surface of the measurement object against the ball.

In such an invention, in either the first support base of the measurement object or the second support base of the measurement object, the combination of the contact portion with the side surface of the measurement object and the pressing means allows displacement in the stretching direction. However, in order to regulate the displacement in the two directions intersecting in the stretching direction, the function corresponding to the combination of the V-groove formed on the bottom surface of the measurement object and the sphere is performed. As a result, the function corresponding to the above-mentioned kinematic mount can be obtained in the measurement object 1st support and the measurement object 2nd support, and the above-mentioned displacement regulation and rotation regulation with respect to the extension direction and the intersection direction thereof can be obtained. Can be done properly.

In the method for measuring the coefficient of linear expansion of the dimension reference device of the present invention, the reference gauge first support has a contact portion between a conical hole and a sphere and a contact portion between a flat surface and a sphere between the bottom surface of the reference gauge. The reference gauge second support base has one or two of the contact portions between the V-groove and the sphere, and the reference gauge second support is formed between the bottom surface of the reference gauge and the contact portion between the conical hole and the sphere, and a flat surface. It is desirable to have a contact portion between the ball and the ball, and a contact portion between the V-groove and the ball, which is not included in the reference gauge first support base.

In the present invention as described above, the reference gauge support base including the reference gauge first support base and the reference gauge second support base has a contact portion between a conical hole and a sphere and a flat surface and a sphere between the bottom surface of the reference gauge. A kinematic mount having three points of a contact portion and a contact portion between the V-groove and the sphere can be configured, and the above-mentioned displacement regulation and rotation regulation with respect to the stretching direction and the intersecting direction thereof can be appropriately performed.

In the method for measuring the coefficient of linear expansion of the dimension reference device of the present invention, the reference gauge first support is formed between the bottom surface of the reference gauge and the contact portion between the conical hole and the sphere and the contact portion between the flat surface and the sphere. The reference gauge second support base has any one of them, and the reference gauge second support base has a contact portion between a conical hole and a sphere and a contact portion between a flat surface and a sphere between the bottom surface of the reference gauge. 1 The reference gauge has a contact portion that is not provided on the support base, and either the reference gauge first support base or the reference gauge second support base has a contact portion between one side surface of the reference gauge and a ball, and the reference gauge. It is desirable to have a pressing means for pressing the side surface against the ball.

In such an invention, in either the reference gauge first support or the reference gauge second support, the combination of the side surface of the reference gauge and the pressing means intersects in the stretching direction while allowing displacement in the stretching direction. In order to regulate the displacement in two directions, the function corresponding to the combination of the V-groove formed on the bottom surface of the reference gauge and the sphere is performed. As a result, in the reference gauge 1st support and the reference gauge 2nd support, the function corresponding to the above-mentioned kinematic mount can be obtained, and the above-mentioned displacement regulation and rotation regulation with respect to the extension direction and the intersection direction thereof are appropriately applied. Can be done.

In the method for measuring the coefficient of linear expansion of the dimensional reference device of the present invention, the support adapter is attached to the reference gauge and supported by the reference gauge support, or is attached to the measurement object and is attached to the measurement object support. It is desirable to use a supported support adapter.

In the present invention as described above, even when supporting by the above-mentioned kinematic mount or the like, it is sufficient to form a conical hole, a V-groove, or the like in the support adapter, and it is not necessary to directly form the reference gauge or the object to be measured. Can be facilitated.

In the method for measuring the coefficient of linear expansion of the dimension reference device of the present invention, it is desirable to have a pressurizing means for pressurizing the reference gauge downward.

In such an invention, even when the reference gauge is lightweight, it can be stably supported by the reference gauge support base by applying pressure downward.
The object to be measured is generally heavier than the reference gauge, and pressurization is not particularly required. However, when the object to be measured is lightweight, the same pressurization may be performed.

In the present invention, the reference gauge is manufactured from a material having an extremely low expansion coefficient or a zero expansion coefficient whose expansion can be ignored in terms of accuracy in the temperature change between the first temperature and the second temperature, or It is desirable that it is manufactured from a material with a known coefficient of expansion.

In the present invention as described above, when the reference gauge is manufactured from a material having an extremely low expansion coefficient or a zero expansion coefficient, the temperature correction of the length of the reference gauge between the first temperature and the second temperature is omitted. can do. On the other hand, when the reference gauge is manufactured from a material having a known expansion coefficient, the length of the reference gauge at each temperature can be calculated with high accuracy by temperature correction at the first temperature and the second temperature. In either case, since the reference gauge length at each temperature can be made accurate, the comparative measurement at the first temperature and the comparative measurement at the second temperature can be performed with high accuracy.
As such a reference gauge, an existing block gauge with high accuracy can be used.

The linear expansion coefficient measuring device of the dimensional reference device of the present invention uses the dimensional reference device as a measurement object, and is a line of a portion from the first surface to the second surface of the measurement object separated in the stretching direction of the measurement object. A linear expansion coefficient measuring device of a dimensional reference device for measuring an expansion coefficient, which has a first reference surface and a second reference surface corresponding to the first surface and the second surface, and from the first reference surface. A reference gauge having a known length to the second reference surface, a constant temperature bath capable of accommodating the object to be measured and the reference gauge, adjusting the internal temperature, and having a measurement opening on the measurement surface. A measurement object support base installed inside the constant temperature bath to support the measurement object, a reference gauge support base installed inside the constant temperature bath to support the reference gauge, and the measurement opening. It is characterized by having a three-dimensional measuring machine capable of introducing a measuring probe into a constant temperature bath.

In such an invention, the same effect can be obtained by the procedure as described in the above-described method for measuring the coefficient of linear expansion of the dimension reference device of the present invention.

According to the present invention, it is possible to provide a method and a measuring device for measuring the coefficient of linear expansion of a dimensional reference device, which can measure the coefficient of linear expansion of various lengths with high accuracy and at low cost.

The perspective view which shows the measuring apparatus of 1st Embodiment of this invention. The perspective view which shows the step gauge which is the measurement object of the 1st Embodiment. The perspective view which shows the reference block gauge which is the reference gauge of the 1st Embodiment. The perspective view which shows the arrangement of the constant temperature bath, the step gauge and the reference block gauge of the 1st Embodiment. The side view which shows the 1st support stand of the measurement object of the 1st Embodiment. The side view which shows the 2nd support stand of the measurement object of the 1st Embodiment. The side view which shows the reference gauge 1st support of the 1st Embodiment. The side view which shows the reference gauge 2nd support of the 1st Embodiment. The perspective view which shows the bottom surface side of the reference block gauge of the 1st Embodiment. The flowchart which shows the measurement procedure of the 1st Embodiment. The side view which shows the installation state of the 1st Embodiment. The perspective view which shows the measurement operation of the 1st Embodiment. The perspective view which shows the support adapter of the 2nd Embodiment of this invention. The perspective view which shows the constant temperature bath of 3rd Embodiment of this invention. The perspective view which shows the arrangement of the constant temperature bath, the step gauge and the reference block gauge of the 3rd Embodiment. The side view which shows the 1st support stand of the measurement object of 4th Embodiment of this invention. The side view which shows the 2nd support stand of the measurement object of 4th Embodiment. The side view which shows the reference gauge 1st support stand of 5th Embodiment of this invention. The side view which shows the reference gauge 2nd support of the 5th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
In FIG. 1, the linear expansion coefficient measuring device 1 of the present embodiment uses a step gauge 10 which is a dimensional reference device as a measurement object, and measures the linear expansion coefficient with high accuracy.
For this purpose, the linear expansion coefficient measuring device 1 includes a constant temperature bath 30 that accommodates the step gauge 10 and maintains the temperature at a predetermined temperature, a reference block gauge 20 as a reference gauge that is also accommodated in the constant temperature bath 30, and a reference block gauge. A three-dimensional measuring machine 40 for comparing and measuring the length of the step gauge 10 with reference to 20 is provided.

The coordinate measuring machine 40 has a surface plate 41, and a head 44 is supported on the upper surface thereof by a column 42 and a crossbar 43. A ram 45 extending downward is installed in the head 44, and a probe 46 is supported at the tip thereof.
In the coordinate measuring machine 40, the column 42 is movable in the Y-axis direction with respect to the surface plate 41, the head 44 is movable in the X-axis direction with respect to the crossbar 43, and the ram 45 is movable with respect to the head 44. It is said that it can be moved in the Z-axis direction. By these three-axis movements, the probe 46 can be moved three-dimensionally with respect to the surface plate 41.

The constant temperature bath 30 is a device capable of maintaining the temperature inside the box-shaped housing at a desired temperature, is placed on the upper surface of the surface plate 41, and is fixed so that its longitudinal direction is along the Y-axis direction. ..
The constant temperature bath 30 can accommodate the step gauge 10 and the reference block gauge 20 inside by opening and closing the upper surface side.
A plurality of measurement openings 31 having an openable / closable lid are formed on the upper surface of the constant temperature bath 30.

Inside the constant temperature bath 30, the step gauge 10 is supported so that its stretching direction Lt is along the Y-axis direction. Further, the reference block gauge 20 is arranged on the upper surface side of the step gauge 10 (the side of the step gauge 10 facing the measurement opening 31), and its stretching direction Lr is parallel to the step gauge 10 along the Y-axis direction. Is supported by.

As shown in FIG. 2, the step gauge 10 which is an object to be measured has a prismatic main body extending in the stretching direction Lt, and its upper surface, bottom surface and each side surface have heights in two directions intersecting the stretching direction Lt. It is parallel to either the direction Ht or the width direction Wt.
On the upper surface of the step gauge 10, a plurality of block gauge-shaped convex portions 13 are arranged in the stretching direction Lt. The length of the extending direction Lt of each convex portion 13 is Dp, and the interval of the extending direction Lt of the concave portion between each convex portion 13 is Dc.
In the present embodiment, the surface of the convex portion 13 at one end of the step gauge 10 is designated as the first surface 11, and the surface of the convex portion 13 at the other end is designated as the second surface 12, and these first surfaces. The distance between 11 and the second surface 12 is measured as the length Dx of the step gauge 10.

As shown in FIG. 3, the reference block gauge 20 which is a reference gauge is a block gauge extending in the stretching direction Lr, and the upper surface, the bottom surface and each side surface thereof are the height direction Hr and the height direction Hr which is two directions intersecting the stretching direction Lr. It is parallel to any of the width direction Wr.
In the reference block gauge 20, the pair of end faces corresponding to both ends in the stretching direction Lr are the first reference surface 21 and the second reference surface 22.

The reference block gauge 20 has a distance, that is, a length of Drx between the first reference surface 21 and the second reference surface 22. In the reference block gauge 20, the length Drx is a predetermined dimension (for example, the length of the convex portion 13) rather than the length Dx based on the length Dx (nominal dimension, nominal dimension) of the measurement target in the step gauge 10 which is the measurement target. (By Dp) Shorter dimensions are selected.
The reference block gauge 20 has not only a known length Drx but also a highly accurate linear expansion coefficient, and is used for comparative measurement at a first temperature t1 and comparative measurement at a second temperature t2, which will be described later. Can calculate the length Drx at each temperature t1 and t2 with high accuracy from the linear expansion coefficient.

In FIG. 4, these step gauge 10 and the reference block gauge 20 are installed in parallel in the constant temperature bath 30.
In order to support these step gauge 10 and reference block gauge 20, a highly rigid bottom plate 32 is installed in the constant temperature bath 30, and a measurement object support base 50 and a reference gauge support base 60 are installed on the upper surface thereof. ing.

The measurement object support base 50 is composed of a measurement target first support base 51 on the first surface 11 side and a measurement target second support base 52 on the second surface 12 side.
The reference gauge support base 60 is composed of a reference gauge first support base 61 on the first reference surface 21 side and a reference gauge second support base 62 on the second reference surface 22 side.

[Measurement target 1st support 51]
In FIG. 5, the measurement object first support 51 has a base portion 511 installed on the bottom plate 32, and standing portions 512 and 513 are formed along both side edges thereof. The step gauge 10 is housed in the space between the upright portions 512 and 513 and is supported on the base 511.
Two sets of balls 514 and a ball holder 515 are installed side by side in the width direction Wt on the base portion 511. The ball holder 515 has a large number of support balls that roll on the balls 514 and forms so-called free ball bearings or ball casters.

The bottom surface of the step gauge 10 is in contact with two balls 514, and the balls 514 and the ball holder 515 provide a flat surface and a sphere between the first support base 51 of the object to be measured and the bottom surface of the step gauge 10. The contact portion 502 is formed.
Then, the load of the step gauge 10 is supported by the constant temperature bath 30 via the base portion 511 and the bottom plate 32 by these two sets of contact portions 502.

In the contact portion 502, the bottom surface of the step gauge 10 and the ball 514 roll so that the step gauge 10 can be displaced in the stretching direction Lt and the width direction Wt, and the height direction H and the width direction Wt are the central axes. Rotation (yawing and pitching) is possible.
However, the bottom surface of the step gauge 10 and the ball 514 are in contact with each other, and the displacement in the height direction Ht is restricted. Further, since there are two sets of balls 514, rotation (rolling) about the drawing direction Lt as a central axis is also regulated.

A ball 514 and a ball holder 515 similar to the contact portion 502 between the base portion 511 and the contact portion 502 are installed between the upright portion 512 and the side surface of the step gauge 10, thereby forming a contact portion 504 between the flat surface and the ball. ing.
Between the upright portion 513 and the side surface of the step gauge 10, a ball 514 and a ball holder 515 similar to the contact portion 502 between the base portion 511 and the base portion 511 are installed. Further, a compression coil spring 516 is installed between the ball holder 515 and the upright portion 513. The pressing means 505 is formed by these balls 514, the ball holder 515, and the compression coil spring 516.

The step gauge 10 is pressed by the pressing means 505 along the width direction Wt and is pressed against the upright portion 512 via the contact portion 504, and the displacement is regulated in the width direction Wt. However, since the pressing means 505 and the contact portion 504 come into contact with the side surface of the step gauge 10 via the ball 514, the displacement in other directions is not regulated, and the rotation about each direction is regulated. Nor.

Therefore, in the measurement object first support base 51, the displacement of the step gauge 10 along the height direction Ht is regulated while the load of the step gauge 10 is supported by the two sets of contact portions 502. Further, the contact portion 504 and the pressing means 505 also regulate the displacement of the step gauge 10 along the width direction Wt, whereby the direction of the extension direction Lt of the step gauge 10 is also determined.
On the other hand, in the measurement object first support 51, displacement in the stretching direction Lt is allowed, pitching and yawing are also allowed, and expansion and contraction of the stretching direction Lt is allowed when the step gauge 10 is thermally deformed. can do.

[Measuring object second support 52]
In FIG. 6, the measurement object second support base 52 has a base portion 521 installed on the bottom plate 32 and a support portion 522 on which the lower surface of the step gauge 10 is placed.
A ball 524 and a ball holder 525 are installed on the base 521. The ball holder 525 has a large number of support balls that roll on the balls 524, forming so-called free ball bearings or ball casters.

A conical hole 529 is formed on the lower surface of the support portion 522, and the ball 524 is fitted into the conical hole 529.
These conical holes 529 and balls 524 form a contact portion 501 between the conical hole and the sphere.

Therefore, in the measurement object second support base 52, while the contact portion 501 supports the load of the step gauge 10, the displacement of the step gauge 10 in the height direction Ht, the displacement in the width direction Wt, and the displacement in the stretching direction Lt All are regulated. However, in the contact portion 501, rotation about the ball 524 as the central axis (yawing) about the height direction Ht, rotation about the width direction Wt (pitching), and rotation about the extension direction Lt as the central axis. (Rolling) is all allowed.

In this way, the step gauge 10 is supported by the measurement object first support 51 and the measurement object second support 52.
As a result, the step gauge 10 is restricted in the position of Wt in the width direction in each of the first support stand 51 of the measurement object and the second support stand 52 of the measurement object, and the extension direction Lt is the constant temperature bath 30 and the coordinate measuring machine 40. It is supported so as to be aligned in the Y-axis direction of.
The position of the stretching direction Lt is constrained by the contact portion 501 of the measurement object second support 52, but the measurement target first support 51 allows displacement in the stretching direction Lt and expands and contracts due to thermal deformation. Appears mainly on the 11th side of the first surface.

[Reference gauge first support 61]
In FIG. 7, the reference gauge first support base 61 has a base portion 611 arranged above the bottom plate 32 and a support column 612 fixed to the lower surface of the base portion 611, and is supported by the bottom plate 32 by the support column 612. ..
Two sets of balls 614 and a ball holder 615 are installed side by side in the width direction Wr on the base portion 611. The ball holder 515 has a large number of support balls that roll on the balls 514 and forms so-called free ball bearings or ball casters.

Of the two sets of balls 614 and the ball holder 615, one set of balls 614 is in contact with the lower surface of the reference block gauge 20, thereby forming a contact portion 602 between the flat surface and the sphere.
Of the two sets of balls 614 and the ball holder 615, the other set of balls 614 is fitted into a conical hole 619 (see FIG. 9) formed on the lower surface of the reference block gauge 20 so that the conical hole and the sphere are connected. The contact portion 601 is formed.

Therefore, in the reference gauge first support base 61, the load of the reference block gauge 20 is supported by the contact portion 602 between the plane and the sphere and the contact portion 601 between the conical hole and the sphere arranged in the width direction Wr. Displacement of Hr in the height direction, displacement of Wr in the width direction, displacement of Lr in the stretching direction and rotation (rolling) around the stretching direction Lr are regulated, and rotation (yawing) and width about the center axis of Hr in the height direction are regulated. Rotation (pitching) about the direction Wr as the central axis is allowed.

Further, an upright portion 610 is formed on the base portion 611, and between the upright portion 610 and the upper surface of the reference block gauge 20, a ball 614 and a ball holder 615 similar to the contact portion 602, and these are used as the reference block gauge 20. A compression coil spring 617 for urging toward the upper surface is installed, and a pressurizing means 609 for pressurizing the reference block gauge 20 downward is formed by these.
By such a pressurization means 609, in the reference gauge first support 61, even if the weight of the reference block gauge 20 is small, the contact of the contact portions 601, 602 on the lower surface side is surely maintained.

[Reference gauge second support base 62]
In FIG. 8, the reference gauge second support base 62 has a base portion 621, a support column 622, and an upright portion 620 similar to the reference gauge first support base 61. A similar pressurizing means 609 is configured by the ball 624, the ball holder 625, and the compression coil spring 627.
On the other hand, in the reference gauge second support base 62, the contact portion between the V-groove and the sphere is replaced with the contact portion 602 between the flat surface and the sphere and the contact portion 601 between the conical hole and the sphere in the reference gauge first support base 61. 603 is configured.

A ball 624 and a ball holder 625 are installed on the upper surface of the base portion 621. A V-groove 628 is formed on the lower surface of the facing reference block gauge 20 along the stretching direction Lr (see FIG. 9). By fitting the ball 624 into the V-groove 628, the contact portion 603 between the V-groove and the ball is formed.

Therefore, in the reference gauge second support base 62, the load of the reference block gauge 20 is supported by the contact portion 603 between the V groove and the ball, and the displacement in the height direction Hr and the displacement in the width direction Wr are regulated. , Displacement in the stretching direction Lr, rotation around the stretching direction Lr (rolling), rotation around the height direction Hr (yawing), and rotation around the width direction Wr (pitching) are allowed. There is.

In this way, the reference block gauge 20 is supported by the reference gauge first support base 61 and the reference gauge second support base 62.
As a result, the reference block gauge 20 is restricted in the position of Wr in the width direction in each of the reference gauge first support 61 and the reference gauge second support 62, and the extension direction Lr is the constant temperature bath 30 and the coordinate measuring machine 40. It is supported so as to be aligned in the Y-axis direction (that is, the stretching direction Lt of the step gauge 10).
The position of the drawing direction Lr is restricted by the contact portion 601 of the reference gauge first support 61, but the reference gauge second support 62 allows the displacement of the drawing direction Lr, and the expansion and contraction due to thermal deformation is the main. Appears on the 21st side of the first reference surface.

[Measurement operation of coefficient of linear expansion]
FIG. 10 shows a procedure for measuring the linear expansion coefficient of the step gauge 10 using the linear expansion coefficient measuring device 1.
At the start of measurement, first, the constant temperature bath 30 is fixed to the coordinate measuring machine 40 as the linear expansion coefficient measuring device 1, and the step gauge 10 and the reference block gauge 20 are installed inside the constant temperature bath 30 (process S1).

When installing the step gauge 10 and the reference block gauge 20 inside the constant temperature bath 30, first, the measurement object first support 51 and the measurement object second support 52 are installed, and the step gauge 10 is formed by these. To support. Next, the reference gauge first support base 61 and the reference gauge second support base 62 are installed so as to straddle the step gauge 10, and the reference block gauge 20 is supported by these.

As shown in FIG. 11, when the step gauge 10 and the reference block gauge 20 are installed, the positions of the respective stretching directions Lt and Lr are adjusted, and the second surface 12 and the second reference surface 22 are the same. Keep it flat.
Here, since the length Drx of the reference block gauge 20 is set shorter than the length Dx of the step gauge 10 by the length Dx of the convex portion 13, the second reference surface 22 and the second surface 12 are aligned. In such a case, the first reference surface 21 does not reach the first surface 11 by the length Dx of the convex portion 13, and the convex portion 13 closest to the first surface 11 does not cover the upper surface side with the reference block gauge 20. Be in a state.

After installing the step gauge 10 and the reference block gauge 20 (process S1), input the measurement length (length Dx of the step gauge 10) into the coordinate measuring machine 40 (process S2), and step gauges at different temperatures. The comparative measurement operation of the length of 10 is executed (processes S3 to S5).
First, with all the measurement openings 31 closed, the internal temperature of the constant temperature bath 30 is set to the first temperature t1, and the temperature is stabilized after a predetermined time (process S3).

When the inside of the constant temperature bath 30 is stabilized at the first temperature t1, the coordinate system of the step gauge 10 and the reference block gauge 20 is determined (process S4).
Specifically, the measurement opening 31 on the first surface 11 side is opened, and the probe 46 of the coordinate measuring machine 40 is introduced. Then, as shown in FIG. 12, the first surface 11 of the step gauge 10 is brought into contact with three or more points to detect the position and inclination. Further, the upper surface and one side surface of the convex portion 13 on which the first surface 11 is set are similarly contacted at three or more points to detect the position and inclination. As a result, the three-dimensional coordinates of the center position of the first surface 11 and the direction Lt in the stretching direction of the step gauge 10 are acquired.

Similarly, the probe 46 detects contact between the first reference surface 21 of the reference block gauge 20 and the adjacent upper surface and side surface, and the three-dimensional coordinates of the center position of the first reference surface 21 and the stretching direction of the reference block gauge 20. Get the orientation of Lr.
Further, the probe 46 is introduced through the measurement opening 31 on the second surface 12 side, the second surface 12 of the step gauge 10 and the second reference surface 22 of the reference block gauge 20 are measured, and the second surface 12 and the second surface 12 and the second surface are measured. The three-dimensional coordinates of the center position of the reference surface 22 are acquired.

After the coordinate system of the step gauge 10 and the reference block gauge 20 is determined (process S4), the dimensions of the step gauge 10 and the reference block gauge 20 are comparatively measured, and the temperature at that time is measured and recorded (process). S5).
Specifically, under the coordinate system by the process S4, the distance between the center position of the first surface 11 and the center position of the first reference surface 21, the center position of the second surface 12 and the center of the second reference surface 22 The first surface 11 and the second surface 12 are calculated from the distance between the first reference surface 21 and the second reference surface 22 (the length Drx of the reference block gauge 20) based on the distance from the position. The distance (the exact value of the length Dx) can be compared and measured.

As described above, when the distance between the first surface 11 and the second surface 12 can be compared and measured at the first temperature t1, the internal temperature of the constant temperature bath 30 is changed to the second temperature t2 (process S6), and the above-mentioned comparison is performed. The measurement operation (processes S3 to S5) is repeated.
As a result, the length Dx1 at the first temperature t1 and the length Dx2 at the second temperature t2 can be obtained. Therefore, the length D of the step gauge 10 is the first surface 11 and the second surface of the step gauge 10. It can be calculated as the linear expansion coefficient α = [(Dx1-Dx2) / D] / (t1-t2) in the section between 12 and 12 (process S7). The length D may be either the measured length Dx1 or the length Dx2, or an average value, or may be the nominal length of the step gauge 10, and in any case, the thermal deformation ΔD = (Dx1). Since it is sufficiently large with respect to −Dx2), it does not affect the calculation of the linear expansion coefficient α.

[Effect of the first embodiment]
According to this embodiment, the following effects can be obtained.
Since the length of the step gauge 10 which is the object to be measured is measured by using the coordinate measuring machine 40, the linear expansion coefficient of the step gauge 10 of various lengths can be accurately measured without using an expensive light wave interferometer. Can be measured.

Further, in the present embodiment, when the length of the step gauge 10 is measured by using the coordinate measuring machine 40, the reference block gauge 20 is used as a reference for the length, and the length is comparatively measured with respect to the reference block gauge 20. I do. Therefore, the result of the length measurement does not depend on the accuracy of the scale of the coordinate measuring machine 40, but depends exclusively on the accuracy of the reference block gauge 20, and even if the step gauge 10 is lengthened, the accuracy is high. Can be secured.

In the present embodiment, when performing comparative measurement, the calculation of the center coordinates of the first reference surface 21, the second reference surface 22, the first surface 11 and the second surface 12, and the stretching of the reference block gauge 20 and the step gauge 10 are performed. The coordinate system determination (process S4 in FIG. 11) including the calculation of the inclination with respect to the directions Lr and Lt is performed.
Therefore, even when the first reference surface 21 and the second reference surface 22 of the reference block gauge 20 and the first surface 11 and the second surface 12 of the step gauge 10 are tilted with respect to the stretching directions Lr and Lt. The detection position by the coordinate measuring machine 40 can be corrected from the distance from the contact position of the probe 46 to the center coordinates on each surface and the inclination of each surface.
Then, each coordinate system is determined according to the current state of the reference block gauge 20 and the step gauge 10, and the length is measured under the coordinate system to improve the accuracy. The accuracy can be maintained high.

In the present embodiment, the first surface 11 and the second surface 12 which are the measurement target parts of the step gauge 10 are arranged on the measurement opening 31 side, and the reference block gauge 20 is arranged on the same side to be compared. The first reference surface 21 and the second reference surface 22 can be arranged close to the first surface 11 and the second surface 12, and the measurement accuracy can be improved and the measurement operation can be made more efficient and speedy.

In the present embodiment, the length Drx from the first reference surface 21 to the second reference surface 22 of the reference block gauge 20 is more convex than the length Dx from the first surface 11 to the second surface 12 of the step gauge 10. The length Dp of one part 13 was set short.
Therefore, even if the reference block gauge 20 is arranged on the measurement opening 31 side of the step gauge 10 and the surface of the step gauge 10 is covered with the reference block gauge 20, the reference block gauge 20 is near the end on the first surface 11 side. Since the length of the block gauge 20 is short, the surface of the step gauge 10 is exposed on the measurement opening 31 side. Therefore, in determining the coordinate system described above, the surface of the step gauge 10 can be detected without interfering with the reference block gauge 20 by bringing the probe 46 of the coordinate measuring machine 40 into contact with the exposed surface. it can.

In the present embodiment, since the second reference surface 22 and the second surface 12 are arranged in the same plane, when the reference block gauge 20 is made shorter than the step gauge 10 by a predetermined length as described above, the same plane is formed. The difference in length between the reference block gauge 20 and the step gauge 10 is maximized at the end (the side of the first surface 11 and the first reference surface 21) opposite to the side where the measure is set, and the three-dimensional measuring machine 40 The margin when performing surface detection by the probe 46 can be maximized.

In the present embodiment, in the measurement object first support 51, the combination of the contact portion 504 with the side surface of the step gauge 10 and the pressing means 505 intersects the stretching direction Lt while allowing the displacement of the stretching direction Lt 2 In order to regulate the displacement in the direction (Ht in the height direction, Wt in the width direction), this combination provides a function corresponding to the combination of the V-groove and the sphere of the kinematic mount. As a result, the measurement object 1st support 51 and the measurement object 2nd support 52 can obtain the function corresponding to the kinematic mount, and the displacement regulation and the rotation regulation with respect to the extension direction Lt and its intersection direction can be obtained. Can be done properly.

In the present embodiment, the reference gauge support base 60 is composed of the reference gauge first support base 61 and the reference gauge second support base 62, and the contact portion 601 between the conical hole and the sphere between the reference gauge support base 60 and the bottom surface of the reference block gauge 20. A kinematic mount having three points, a contact portion 602 between a flat surface and a sphere and a contact portion 603 between a V groove and a sphere, can be constructed, and the extension direction Lr and its intersection direction (height direction Hr, width direction Wr) can be configured. ) Can be appropriately regulated in displacement and rotation.

In the present embodiment, since the pressurizing means 609 that pressurizes the reference block gauge 20 downward is provided, even if the reference block gauge 20 is lightweight, the reference gauge first support 61 and the reference can be obtained by pressurizing the reference block gauge 20 downward. Support by the gauge second support base 62 can be stably performed.

In addition, this embodiment can correspond to the case where the length of the step gauge 10 is shorter, or the case where the length between the convex portions 13 of the intermediate portion of the step gauge 10 is measured.
In FIG. 11, when the length of the intermediate portion of the step gauge 10 is set, the first surface 11 is set on the convex portion 13 of the intermediate portion as shown by the alternate long and short dash line, and the reference block gauge 20 having the corresponding length is set. The first reference surface 21 may be set using the probe 46, and each measurement may be performed with the probe 46. At this time, when the probe 46 is introduced into the constant temperature bath 30, the nearest one of the plurality of measurement openings 31 may be used.

[Second Embodiment]
FIG. 13 shows a second embodiment of the present invention.
In the first embodiment described above, when the reference block gauge 20 is supported by the reference gauge first support 61 and the reference gauge second support 62, the conical hole 619 and the V groove 628 are directly placed on the lower surface of the reference block gauge 20. Formed.

On the other hand, in the second embodiment, as shown in FIG. 13, the support adapters 71 and 72 are attached to the reference block gauge 20, and a conical hole 619 and a V groove 628 are formed on the lower surface of each.
Since the configuration of the second embodiment is the same as that of the first embodiment described above except for the support portion of the reference block gauge 20, duplicate description will be omitted, and only the difference portion will be described below.

The support adapter 71 is installed at a position supported by the reference gauge first support base 61 of the reference block gauge 20. The support adapter 71 has a support plate 711 and a fixing member 712, and is fixed to the reference block gauge 20 by sandwiching the reference block gauge 20 between them.
The support adapter 72 is installed at a position supported by the reference gauge second support base 62 of the reference block gauge 20. The support adapter 72 has a support plate 721 and a fixing member 722, and is fixed to the reference block gauge 20 by sandwiching the reference block gauge 20 between them.

A conical hole 619 is formed on the lower surface of the support plate 711, and a V groove 628 is formed on the lower surface of the support plate 711.
Utilizing these, between the support adapters 71 and 72 and the reference gauge first support 61 and the reference gauge second support 62, the lower surface of the reference block gauge 20 of the first embodiment (see FIG. 9) Similarly, a contact portion 601 between the conical hole and the sphere, a contact portion 602 between the flat surface and the sphere, and a contact portion 603 with the V groove are formed.

In such an embodiment, the effects of the first embodiment described above can be obtained without forming a conical hole 619 and a V-groove 628 on the lower surface of the reference block gauge 20.
Since it is not necessary to form a conical hole 619 and a V-groove 628 on the lower surface of the reference block gauge 20, by sharing the support adapters 71 and 72, a general-purpose reference block gauge 20 can be used and can be used in various dimensions. Correspondence can be easily performed.

[Third Embodiment]
14 and 15 show a third embodiment of the present invention.
In the first embodiment described above, a measurement opening 31 for introducing the probe 46 is formed on the upper surface of the constant temperature bath 30, and inside the constant temperature bath 30, the upper surface side of the step gauge 10 (the side where the measurement opening 31 is located) is formed. ), And the reference block gauge 20 was arranged in parallel on the same side.

On the other hand, in the third embodiment, as shown in FIGS. 14 and 15, a measurement opening 31A for introducing the probe 46 is formed on the side surface of the constant temperature bath 30A, and the step gauge 10 is provided along the same side surface. In addition to being arranged, the reference block gauge 20 is arranged in parallel between the same side surface and the step gauge 10.
Also in such an embodiment, the same effect as that of the above-described first embodiment can be obtained.

[Fourth Embodiment]
16 and 17 show a fourth embodiment of the present invention.
In the first embodiment described above, in the measurement object first support 51 (see FIG. 5), two contact portions 502 between the flat surface and the sphere are formed between the lower surface of the step gauge 10 and the step gauge 10. The pressing means 505 and the contact portion 504 were formed so as to be sandwiched from the side surface. Further, in the measurement object second support 52 (see FIG. 6), a contact portion 501 between the conical hole and the sphere was formed between the lower surface of the step gauge 10 and the lower surface of the step gauge 10.

On the other hand, in the fourth embodiment, in the measurement object first support 51A (see FIG. 16), the contact portion 502 between the flat surface and the sphere and the contact between the conical hole and the sphere between the lower surface of the step gauge 10 and the sphere. A portion 501 (conical hole 519) is formed, and in the second support base 52A (see FIG. 17) of the object to be measured, a contact portion 503 (V groove 528) between the V groove and the ball is provided between the lower surface of the step gauge 10. Is forming.
In such an embodiment, a configuration corresponding to a kinematic mount can be formed between the step gauge 10 and the measurement object first support 51A and the measurement object second support 52A.

A contact portion 501 between the conical hole and the sphere is formed between the first support base 51A of the measurement object and the step gauge 10, and a flat surface and a sphere are formed between the second support base 52A of the measurement object and the step gauge 10. The contact portion 502 with and the contact portion 503 between the V-groove and the sphere may be formed.

[Fifth Embodiment]
18 and 19 show a fifth embodiment of the present invention.
In the first embodiment described above, in the reference gauge first support 61 (see FIG. 7), the contact portion 601 between the conical hole and the sphere between the lower surface of the reference block gauge 20 and the contact portion 602 between the flat surface and the sphere. In addition, in the reference gauge second support base 62 (see FIG. 8), a contact portion 603 between the V-groove and the sphere was formed between the lower surface of the reference block gauge 20 and the lower surface of the reference block gauge 20.

On the other hand, in the fifth embodiment, in the reference gauge first support 61A (see FIG. 18), two contact portions 602 between the flat surface and the sphere are formed between the lower surface of the reference block gauge 20 and the reference block. A pressing means 605 (ball 614, ball holder 615, compression coil spring 616) and a contact portion 604 (ball 614, ball holder 615) are formed so as to sandwich the gauge 20 from the side surface. Further, in the reference gauge second support base 62A (see FIG. 19), a contact portion 601 (conical hole 629) between the conical hole and the sphere is formed between the reference block gauge 20 and the lower surface.
Also in this embodiment as described above, a configuration corresponding to a kinematic mount can be formed between the reference block gauge 20, the reference gauge first support base 61A, and the reference gauge second support base 62A.

A contact portion 603 between the V-groove and the sphere and a contact portion 602 between the flat surface and the sphere are formed between the reference gauge first support base 61A and the reference block gauge 20, and the reference gauge second support base 62A and the reference block are formed. A contact portion 601 between the gauge 20 and the conical hole and the sphere may be formed.

[Modification example]
The present invention is not limited to the configuration of each of the above-described embodiments, and modifications within the range in which the object of the present invention can be achieved are included in the present invention.
For example, in each embodiment, in the reference gauge 1st support 61, 61A and the reference gauge 2nd support 62, 62A, the pressurization means 609 ensures that the contact portions 601, 602, 603 on the lower surface side are in contact with each other. I was trying to be done.
The pressurizing means 609 is not limited to a mechanical one using compression coil springs 617 and 627, and a non-contact urging means using fluid pressure, fluid flow, electromagnetic force, etc. may be used. Good.
Further, if the weight of the reference block gauge 20 is sufficient, the pressurizing means 609 may be omitted.

In the first embodiment described above, the length Dx from the first surface 11 to the second surface 12 was measured as the length of the step gauge 10. However, by setting both end faces of the step gauge 10 as the first surface 11 and the second surface 12, the length of the step gauge 10 and the coefficient of linear expansion between them can be measured. Further, as described with reference to FIG. 10, by setting the first surface 11 and the second surface 12 to the end surface of the convex portion 13 of the intermediate portion of the step gauge 10, the length and the coefficient of linear expansion of the intermediate portion are measured. You can also do it.

In each of the above-described embodiments, the step gauge 10 is used as the measurement target, but the measurement target may be a block gauge or another dimensional reference device.
Further, the reference gauge is not limited to the reference block gauge 20, and a dedicated reference gauge or a master gauge which is a step gauge 10 similar to the object to be measured and calibrated with high accuracy may be used.
At this time, the reference gauge is manufactured from a material having an extremely low expansion coefficient or zero expansion coefficient whose expansion can be ignored in terms of accuracy in the temperature change between the first temperature t1 and the second temperature t2, or expansion. It is desirable that it is manufactured from a material with a known coefficient.

In the above embodiment, the second reference surface 22 of the reference block gauge 20 which is the reference gauge and the second surface 12 of the step gauge 10 which is the measurement target are aligned on the same plane, but the first reference surface 21 and the first are The surface 11 may be aligned with the surface 11, or both ends of the reference gauge and the object to be measured may not be aligned.
However, by aligning either end, the difference in length between the reference gauge and the object to be measured is maximized at the end opposite to the coplanar side, and the surface of the coordinate measuring machine probe is used. The margin for detection can be maximized.

The present invention can be used for a method and a measuring device for measuring the coefficient of linear expansion of a dimensional reference device.

1 ... Linear expansion coefficient measuring device, 10 ... Step gauge which is an object to be measured, 11 ... First surface, 12 ... Second surface, 13 ... Convex part, 20 ... Reference block gauge which is a reference gauge, 21 ... First reference Surface, 22 ... 2nd reference surface, 30, 30A ... Constant temperature bath, 31 ... Measurement opening, 31A ... Measurement opening, 32 ... Bottom plate, 40 ... Three-dimensional measuring machine, 41 ... Plate, 42 ... Column, 43 ... Crossbar, 44 ... head, 45 ... ram, 46 ... probe, 50 ... measurement object support, 501 ... contact part between conical hole and sphere, 502 ... contact part between flat surface and sphere, 503 ... V groove and sphere Contact part with, 504 ... Contact part between flat surface and sphere, 505 ... Pressing means, 51, 51A ... Measurement object 1st support base, 511 ... Base, 512 ... Standing part, 513 ... Standing part, 514 ... Ball, 515 ... ball holder, 516 ... compression coil spring, 319 ... conical hole, 52, 52A ... object to be measured 2nd support base, 521 ... base, 522 ... support, 524 ... ball, 525 ... ball holder, 528 ... V groove , 529 ... Conical hole, 60 ... Reference gauge support, 601 ... Conical hole and sphere contact part, 602 ... Flat surface and sphere contact part, 603 ... V groove and sphere contact part, 604 ... Flat surface and sphere Contact part, 605 ... Pressing means, 609 ... Pressurizing means, 61, 61A ... Reference gauge first support base, 610 ... Standing part, 611 ... Base, 612 ... Support, 614 ... Ball, 615 ... Ball holder, 616 ... compression coil spring, 617 ... compression coil spring, 619 ... conical hole, 62, 62A ... reference gauge second support base, 620 ... standing part, 621 ... base, 622 ... support, 624 ... ball, 625 ... ball holder, 628 ... V groove, 629 ... Conical hole, 71,72 ... Support adapter, 711,721 ... Support plate, 712,722 ... Fixing member, Dx ... Length of object to be measured, Drx ... Reference gauge length, Hr ... Reference Gauge height direction, Ht: height direction of measurement object, Lr: extension direction of reference gauge, Lt: extension direction of measurement object, T ... temperature, t1 ... first temperature, t2 ... second temperature, To ... Reference temperature, Wr ... Reference gauge width direction, Wt ... Measurement object width direction, α ... Linear expansion coefficient, ΔL ... Length change amount.

Claims (8)

A method for measuring the coefficient of linear expansion of a dimensional reference device, which measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface, which is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Prepare and
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The first support for the object to be measured is one of a contact portion between a conical hole and a sphere, a contact portion between a flat surface and a sphere, and a contact portion between a V groove and a sphere between the bottom surface of the measurement object. Have one or two,
The second support base of the measurement object is the measurement of the contact portion between the conical hole and the sphere, the contact portion between the flat surface and the sphere, and the contact portion between the V groove and the sphere between the bottom surface of the measurement object. It is assumed that the object has a contact part that is not on the first support base.
The object to be measured and the reference gauge are supported in parallel inside the constant temperature bath.
With the internal temperature of the constant temperature bath as the first temperature and the length from the first reference surface to the second reference surface as a reference, the length from the first surface to the second surface is comparatively measured.
The internal temperature of the constant temperature bath is defined as the second temperature, and the length from the first surface to the second surface is comparatively measured with reference to the length from the first reference surface to the second reference surface.
The coefficient of linear expansion of the object to be measured is calculated from the length from the first surface to the second surface at the first temperature and the length from the first surface to the second surface at the second temperature. A method for measuring the coefficient of linear expansion of a dimensional reference device. A method for measuring the coefficient of linear expansion of a dimensional reference device, which measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface, which is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Prepare and
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The first support for the object to be measured has any one of a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the measurement object.
The measurement object second support is in contact with the bottom surface of the measurement object, which is a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere, which is not on the measurement object first support. Has a part
Either the first support of the measurement object or the second support of the measurement object presses the contact portion between one side surface of the measurement object and the sphere and the side surface of the measurement object against the sphere. Assuming that it has a pressing means,
The object to be measured and the reference gauge are supported in parallel inside the constant temperature bath.
With the internal temperature of the constant temperature bath as the first temperature and the length from the first reference surface to the second reference surface as a reference, the length from the first surface to the second surface is comparatively measured.
The internal temperature of the constant temperature bath is defined as the second temperature, and the length from the first surface to the second surface is comparatively measured with reference to the length from the first reference surface to the second reference surface.
The coefficient of linear expansion of the object to be measured is calculated from the length from the first surface to the second surface at the first temperature and the length from the first surface to the second surface at the second temperature. A method for measuring the coefficient of linear expansion of a dimensional reference device. A method for measuring the coefficient of linear expansion of a dimensional reference device, which measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface, which is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Prepare and
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The first support for the object to be measured has any one of a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the measurement object.
The reference gauge first support is one of a conical hole and a sphere contact portion, a flat surface and a sphere contact portion, and a V groove and a sphere contact portion between the reference gauge first support base. Or have two
The reference gauge second support is the reference gauge second among the contact portion between the conical hole and the sphere, the contact portion between the flat surface and the sphere, and the contact portion between the V groove and the sphere between the bottom surface of the reference gauge. 1 It is assumed that the support has a contact part that is not on the support base.
The object to be measured and the reference gauge are supported in parallel inside the constant temperature bath.
With the internal temperature of the constant temperature bath as the first temperature and the length from the first reference surface to the second reference surface as a reference, the length from the first surface to the second surface is comparatively measured.
The internal temperature of the constant temperature bath is defined as the second temperature, and the length from the first surface to the second surface is comparatively measured with reference to the length from the first reference surface to the second reference surface.
The coefficient of linear expansion of the object to be measured is calculated from the length from the first surface to the second surface at the first temperature and the length from the first surface to the second surface at the second temperature. A method for measuring the coefficient of linear expansion of a dimensional reference device. A method for measuring the coefficient of linear expansion of a dimensional reference device, which measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface, which is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Prepare and
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The reference gauge first support base has any one of a contact portion between a conical hole and a sphere and a contact portion between a flat surface and a sphere between the bottom surface of the reference gauge.
The reference gauge second support has a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the reference gauge and the contact portion which is not on the reference gauge first support. And
Either the reference gauge first support base or the reference gauge second support base has a contact portion between one side surface of the reference gauge and a ball, and a pressing means for pressing the side surface of the reference gauge against the ball. As you have
The object to be measured and the reference gauge are supported in parallel inside the constant temperature bath.
With the internal temperature of the constant temperature bath as the first temperature and the length from the first reference surface to the second reference surface as a reference, the length from the first surface to the second surface is comparatively measured.
The internal temperature of the constant temperature bath is defined as the second temperature, and the length from the first surface to the second surface is comparatively measured with reference to the length from the first reference surface to the second reference surface.
The coefficient of linear expansion of the object to be measured is calculated from the length from the first surface to the second surface at the first temperature and the length from the first surface to the second surface at the second temperature. A method for measuring the coefficient of linear expansion of a dimensional reference device. A linear expansion coefficient measuring device of a dimensional reference device that measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface that is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Have,
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The first support for the object to be measured is one of a contact portion between a conical hole and a sphere, a contact portion between a flat surface and a sphere, and a contact portion between a V groove and a sphere between the bottom surface of the measurement object. Have one or two,
The second support base of the measurement object is the measurement of the contact portion between the conical hole and the sphere, the contact portion between the flat surface and the sphere, and the contact portion between the V groove and the sphere between the bottom surface of the measurement object. An object linear expansion coefficient measuring device of a dimensional reference device, which has a contact portion that is not on the first support base of an object. A linear expansion coefficient measuring device of a dimensional reference device that measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface that is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Have,
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The first support for the object to be measured has any one of a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the measurement object.
The measurement object second support is in contact with the bottom surface of the measurement object, which is a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere, which is not on the measurement object first support. Has a part
Either the first support of the measurement object or the second support of the measurement object presses the contact portion between one side surface of the measurement object and the sphere and the side surface of the measurement object against the sphere. A linear expansion coefficient measuring device for a dimension reference device, which comprises a pressing means. A linear expansion coefficient measuring device of a dimensional reference device that measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface that is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Have,
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The first support for the object to be measured has any one of a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the measurement object.
The reference gauge first support is one of a conical hole and a sphere contact portion, a flat surface and a sphere contact portion, and a V groove and a sphere contact portion between the reference gauge first support base. Or have two
The reference gauge second support is the reference gauge first among the contact portion between the conical hole and the sphere, the contact portion between the flat surface and the sphere, and the contact portion between the V groove and the sphere between the bottom surface of the reference gauge. 1 A coefficient of linear expansion measuring device for a dimension reference device, which has a contact portion that is not provided on a support base. A linear expansion coefficient measuring device of a dimensional reference device that measures the coefficient of linear expansion of a portion of the object to be measured from the first surface to the second surface that is separated from the object to be measured in the stretching direction of the object to be measured. And
A reference gauge having a first reference surface and a second reference surface corresponding to the first surface and the second surface, and having a known length from the first reference surface to the second reference surface.
A constant temperature bath that can accommodate the object to be measured and the reference gauge, can adjust the internal temperature, and has a measurement opening on the measurement surface.
A measurement object support base installed inside the constant temperature bath to support the measurement object,
A reference gauge support base installed inside the constant temperature bath to support the reference gauge, and
A three-dimensional measuring machine capable of introducing a measuring probe from the measuring opening into the constant temperature bath,
Have,
The measurement object support includes a measurement object first support and a measurement object second support.
The first support for the measurement object and the second support for the measurement object regulate the displacement of the measurement object in the two directions intersecting the stretching directions, respectively, and the central axis is the two directions intersecting the stretching directions. Allowing the rotation of the object to be measured
One of the first support for the measurement object and the second support for the measurement object regulates the displacement of the measurement object in the stretching direction, and the other one regulates the displacement of the measurement object in the stretching direction. Tolerate,
Either one of the first support for the measurement object and the second support for the measurement object regulates the rotation of the measurement object with the stretching direction as the central axis, and the other one is centered on the stretching direction. While allowing the measurement object to rotate as an axis,
The reference gauge support base includes a reference gauge first support base and a reference gauge second support base.
The reference gauge first support and the reference gauge second support each regulate the displacement of the reference gauge in two directions intersecting the stretching direction, and the central axis is the two directions intersecting the stretching direction. Allows rotation of the reference gauge,
One of the reference gauge first support and the reference gauge second support regulates the displacement of the reference gauge in the stretching direction, and one of the other allows the displacement of the reference gauge in the stretching direction.
One of the reference gauge first support and the reference gauge second support regulates the rotation of the reference gauge with the stretching direction as the central axis, and one of the other controls the rotation of the reference gauge with the stretching direction as the central axis. Allows rotation of the reference gauge
The reference gauge first support base has any one of a contact portion between a conical hole and a sphere and a contact portion between a flat surface and a sphere between the bottom surface of the reference gauge.
The reference gauge second support has a contact portion between the conical hole and the sphere and a contact portion between the flat surface and the sphere between the bottom surface of the reference gauge and the contact portion which is not on the reference gauge first support. And
Either the reference gauge first support base or the reference gauge second support base has a contact portion between one side surface of the reference gauge and a ball, and a pressing means for pressing the side surface of the reference gauge against the ball. A coefficient of linear expansion measuring device for a dimensional reference device, characterized by having.

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