JP7144035B2 - Hardness reference piece - Google Patents

Description

TECHNICAL FIELD The present invention relates to a hardness reference piece used for precision control and calibration of a hardness tester, and more particularly, to a hardness reference piece that allows the test surface to be evenly and efficiently used while ensuring proper intervals between indentations. Regarding the reference piece.

Rockwell hardness testers and Brinell hardness testers are well known as testers for verifying the surface hardness of industrial materials and industrial products. Hardness reference pieces conforming to standards such as ISO and ISO are generally used. As the hardness reference piece, a disk-shaped piece having a certain thickness and made of a predetermined metal material is widely used.

In such a hardness test, an indenter of a hardness tester is pressed into the test surface of the hardness reference piece described above with a predetermined pressure to form indentations (indentations). If the distance is too large, an error will occur in the measured value, so it is necessary to provide a distance W that is equal to or greater than a predetermined multiple of the diameter d of the indentation. Therefore, as shown in FIG. 11, before the test, a grid-like guide pattern having intervals W in the vertical and horizontal directions is drawn on the test surface of the circular hardness reference piece with a permanent marker or the like. is often used as the target of the hitting point (pressing point) by the indenter.

However, it takes a lot of time and effort for the person conducting the test to accurately draw the aforementioned guide pattern on the hardness reference piece in advance. As a result, it tends to become difficult to accurately position the hitting point as it is used. In addition, since the indentation is formed by using the points of intersection of the vertical and horizontal lines in the lattice pattern as points of impact, the existence of the lines may hinder the accurate measurement of the diameter d of the indentation.

Further, for example, when a grid pattern is displayed at intervals of 9 mm on a square test surface with a side of 100 mm, 100 intersections (rubbing points) can be secured, whereas as shown in FIG. If a grid pattern is displayed on the reference piece with an interval W of 9 mm, and the intersection points separated from the edge by 6.5 mm or more are set as the points, only 76 points can be secured at the maximum. Even if the circular shape were enlarged to have the same surface area as the square shape, the maximum number would be 88. Therefore, it must be said that the circular hardness reference pieces are inefficient in ensuring the number of hit points.

As a solution to this problem, FIG. 1 of Japanese Patent Application Laid-Open No. 61-193046 describes a positioning seal for a hardness reference piece, in which through holes having a diameter larger than the indentation are provided in advance at predetermined intervals. A method has been proposed in which this is attached to a circular test surface, and then the through holes of the positioning seal are used as positioning guides to press the indenter of the hardness tester. As a result, the indenter can be positioned accurately and easily, and the test surface can be efficiently used without waste.

However, in this technique, in addition to the cost of purchasing the positioning seal separately from the hardness reference piece, the person who conducts the test is required to attach the positioning seal accurately to the hardness reference piece in advance. will be required. Moreover, when the positioning seal is partially peeled off due to washing work or the like, it is not easy to reattach it accurately.

JP-A-61-193046

The present invention is intended to solve the above-described problems, and the test surface can be efficiently obtained while ensuring appropriate intervals between indentations without excessively increasing labor and cost for a hardness reference piece. The challenge is to make it available for

Therefore, the present invention provides a flat test surface on which indentations are formed by pressing an indenter of a hardness tester so that all adjacent indentations are aligned with a predetermined width or more of space between adjacent ones. A hardness reference piece on which a guide pattern is displayed as a visual guide when determining the hitting position of the indenter, and the guide pattern is a diagram of a combination of lines. It is characterized in that the center is separated from the edge of the test surface by at least a predetermined distance.

In this way, by providing in advance a guide pattern for aligning and forming indentations at appropriate intervals on the test surface of the hardness reference piece, the person conducting the test does not need to draw the guide pattern by himself/herself. However, by making the guide pattern a line drawing, there is no excessive cost increase for displaying it, and the position of the hitting point is at least a predetermined distance from the edge of the test surface. Separation facilitates efficient use of the test surface while still meeting test method criteria.

Further, in this hardness reference piece, the guide pattern is formed by superimposing a group of parallel lines in which a plurality of straight lines are arranged at regular intervals and a group of parallel lines formed by a plurality of straight lines having the same intervals as the parallel lines. A lattice pattern or diamond pattern formed by intersecting at an angle of 120 degrees, or a third group of parallel lines having the same configuration as the group of parallel lines superimposed on the diamond pattern, and the straight lines intersecting each of the internal angles of 120 degrees. It is an equilateral triangular pattern formed by intersecting to bisect, and the position of the intersection where each straight line intersects is the center position of the hitting point. Even if the position is difficult to see, it is easy to perform alignment by using the direction of the line toward the intersection as a reference.

Alternatively, the guide pattern is a circular pattern in which a plurality of curved circles having a diameter equal to the distance to be secured between adjacent indentations are uniformly arranged in close proximity or in close contact with each other. If the center of each circle is the center position of the hitting point, the alignment of the indenter becomes easier, and the presence of the pattern is less likely to interfere with the measurement of the diameter of the indentation. becomes.

Furthermore, in the hardness reference piece described above, the guide pattern is formed of a curved line having a diameter of 1.3 times or less of the indentation to be formed in the portion to be the hitting position and having a size in which the entire outer periphery of the indentation can be accommodated inside. If the circle is provided with a blank inner portion, and the center of the circle is the center position of the hitting point, the display of the circle of a size close to the indentation can facilitate the alignment of the indenter. It is easier and the placement of the solid circles at the intersections of the lines makes it less of a hindrance when measuring the diameter of the indentation.

Alternatively, the guide pattern is provided with a blank portion having a size and shape that can accommodate all the formed indentations, and no lines are displayed, in the portion that will be the location of the hitting point. If it is characterized by being able to estimate and determine the position, the center position of the hitting point can be relatively easily estimated from the surrounding straight lines and curves, and the part must be completely plain. makes it easier to measure the diameter of the indentation.

In addition, if the hardness reference piece described above is characterized by having a square metal plate on the test surface, it will be more efficient because it will be easier to provide more points than a circular test surface. .

In addition, if the hardness reference piece described above is made of an aluminum alloy, it is easy to handle due to its light specific gravity, and is highly resistant to corrosion and excellent in stability.

According to the present invention, in which a guide pattern for aligning the indentations at appropriate intervals is displayed on the test surface in advance, the test surface can be efficiently arranged while ensuring the appropriate intervals between the indentations without excessively increasing labor and cost. It can be used.

1 is a front view of a hardness reference piece according to a first embodiment of the present invention; FIG. FIG. 3 is a front view showing a modification of the hardness reference piece of FIG. 1; FIG. 3 is a front view showing an application example of the hardness reference piece of FIG. 2; FIG. 5 is a front view of a hardness reference piece according to a second embodiment of the present invention; FIG. 5 is a front view showing a modification of the hardness reference piece of FIG. 4; FIG. 6 is a front view showing an application example of the hardness reference piece of FIG. 5; FIG. 5 is a front view of a hardness reference piece according to a third embodiment of the present invention; FIG. 8 is a front view showing an application example of the hardness reference piece of FIG. 7; FIG. 11 is a front view of a hardness reference piece according to a fourth embodiment of the present invention; FIG. 10 is a front view showing an application example of the hardness reference piece of FIG. 9; It is a front view showing a conventional example.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated, referring drawings.

FIG. 1 shows a hardness reference piece 1A as a first embodiment of the invention. The hardness reference piece 1A consists of a plate-shaped metal piece 10 having a square test surface 10a and a predetermined thickness. A guide pattern 100, which is used as a visual guide when determining the striking position of the indenter so that all adjacent indentations are aligned with a predetermined width or more, is printed in advance. It features the points shown.

The guide pattern 100 is composed of a diagram of a combination of lines, and a group of parallel lines in which a plurality of straight lines are arranged at equal intervals is added to a group of parallel lines of a plurality of straight lines having the same intervals. A grid pattern is provided on the test surface 10a by overlapping and crossing each other at an angle of 90 degrees, and each intersection indicating the center position of the hitting point is at least from the edge of the test surface 10a. They are separated by a predetermined distance or more.

In this way, by providing the guide pattern 100 for aligning the indentations at appropriate intervals on the test surface 10a in advance, the person conducting the test can save the trouble of drawing the guide pattern in advance for determining the hitting position. becomes unnecessary. In addition, since the guide pattern 100 is composed of a line drawing, it is relatively easy to display it, so that introduction of the guide pattern does not involve an excessive increase in cost. Further, the central position of the hit point by the guide pattern 100 is separated from the edge of the test surface 10a by a predetermined distance or more, so that the test surface 10a can be used efficiently and easily while meeting the applicable test standards. there is

For example, in the JIS Brinell hardness test, the distance between the centers of two adjacent indentations (dents) is three times or more the diameter d of the indentation, and the distance from the center of the indentation to the edge of the test surface is the diameter d of the indentation. 2.5 times or more, but when applying this standard with the indentation diameter d of 2.5 mm, if the metal piece 10 has a square test surface 10a with a side of 100 mm, the pitch is 9 mm in length and width to display a lattice pattern as shown in the figure. As a result, it is possible to secure the hitting positions by 100 intersections, which is more efficient than the 76 circular hardness reference pieces shown in FIG.

FIG. 2 shows a hardness reference piece 1B as a modification of the hardness reference piece 1A described above. The hardness reference piece 1B is formed by a curved line having a diameter of 1.3 times or less than the diameter of the indentation formed at the intersecting portion of the guide pattern 100 described above and having a size that allows the entire circumference of the indentation to fit inside. The test surface 11a is characterized by a guide pattern 110 having a plain inner portion of a circle, and the center of the circle is the central position of the hitting point.

As for the size of the circle indicating the hitting position, for example, if the diameter d of the indentation is 2.5 mm, the inner diameter of the inner uncoated portion should be about 3 mm. By providing such a guide pattern 110, it is easier to align the indenter by displaying a circle of a size close to the indentation. It becomes less likely to interfere with the measurement.

FIG. 3 shows a hardness reference piece 1C as an application example of the hardness reference piece 1B described above. In this hardness reference piece 1C, although the guide pattern 120 displayed on the test surface 12a is based on a rectangular grid pattern, the placement of the circles serving as the hitting positions is such that the intervals between adjacent ones are all the same distance. For example, if the interval between the center positions of the hitting points is 9 mm and the distance from the edge is 7 mm, 120 hitting positions can be secured, making the test surface 12a more efficient. can be used for

FIG. 4 shows a hardness reference piece 1D as a second embodiment of the invention. A guide pattern 130 displayed on the test surface 13a of the hardness reference piece 1D is formed by a group of parallel lines in which a plurality of straight lines are arranged at equal intervals, and a group of parallel lines formed by a plurality of straight lines having the same intervals as the parallel lines. are stacked and intersected at an angle of 120 degrees (and 60 degrees) to form a diamond pattern.

In this guide pattern 130, the position of the intersecting point, which is the center position of the hit points, coincides with the center position of the circle of the guide pattern 120 on the hardness reference piece 1C of FIG. If the distance from the edge is 9 mm and the distance from the edge is 7 mm, 120 hitting positions can be secured, so that the test surface 13a can be efficiently used in the same manner as described above. Further, each intersection of the guide pattern 130 may be a guide pattern 140 whose inside is a plain circle like the hardness reference piece 1E shown in FIG.

FIG. 6 shows a hardness reference piece 1F as an application example of the hardness reference piece 1E described above. The hardness reference piece 1F has a blank portion of a size and shape that can accommodate all the formed indentations in the portion corresponding to the position of the intersection of the diamond pattern, which corresponds to the position of the intersection of the diamond pattern. It is characterized in that the central position of the hitting point can be estimated and determined from the line pattern around the blank portion. Specifically, the portion of the hardness reference piece 1E where the circle is arranged is made plain without lines, but the central position of the hitting point can be relatively easily estimated from the surrounding straight line, and the portion The fact that the is completely blank makes it easier to measure the diameter of the indentation.

FIG. 7 shows a hardness reference piece 1G as a third embodiment of the invention. The guide pattern 160 on the hardness reference piece 1G is formed by superimposing a third parallel line group having the same interval between straight lines on the diamond pattern forming the guide pattern 130 on the hardness reference piece 1D in FIG. It is an equilateral triangular pattern formed by intersecting each of the 120-degree interior angles so as to bisect each of them. Since the straight lines intersect at a pitch of 60 degrees, it is easier to align the hitting points.

FIG. 8 shows a hardness reference piece 1H as an application example of the hardness reference piece 1G described above. The guide pattern 170 on the hardness reference piece 1H has a size and shape in which all the formed indentations can be accommodated in the central position of the striking point corresponding to the position of the intersection of the straight lines, similar to the hardness reference piece 1F. A blank area with no display is provided, and the center position of the hitting point can be estimated and determined from the line pattern around the blank area. Position estimation has become easier.

FIG. 9 shows a hardness reference piece 1I as a fourth embodiment of the invention. The hardness reference piece 1I has a guide pattern 180 displayed on its test surface 18a, in which a plurality of circles 181 formed of curved lines having a diameter equal to the distance to be secured between adjacent indentations are in close contact with each other. Circular patterns are uniformly arranged, and the center of each circle 181 is the central position of the hitting point.

Further, the guide pattern 180 is formed at the central portion of each circle 181 at the hitting position by a curved line having a diameter of 1.3 times or less of the indentation to be formed and having a size in which the outer circumference of the indentation can be entirely accommodated inside. A circle 182 is provided with the inner portion being plain, and the center of the circle 182 is the central position of the hitting point. Since the small circle 182 having a size close to the indentation to be formed is displayed at the center of the larger circle 181, the alignment of the indenter is further facilitated, and a plain circle is displayed at the impact point position. Due to the arrangement, it is less likely to interfere with the diameter measurement of the indentation.

FIG. 10 shows a hardness reference piece 1J as an application example of the hardness reference piece 1I described above. The hardness reference piece 1J has a circular pattern in which circles 191 similar to the guide pattern 180 on the hardness reference piece 1I are uniformly arranged in close contact. Instead of arranging it, a cross 192 is displayed, which is a size and shape in which all the impressions can be accommodated in the center of the cross where two straight lines intersect at right angles, and a solid part with no line display is provided. and

The center of the blank portion at the center of the cross 192 is the center position of the hitting point, and the center position of the hitting point can be easily estimated and determined from the line pattern forming the cross shape around it. In addition, since the circle 191 is arranged around the cross 192, rough positioning can be performed in a short period of time. Precise positioning can be done in time.

In the above-described embodiment, the hardness reference pieces 1C, 1D, 1E, 1F, 1G, 1H, 1I, and 1J have 120 hit points. The number of hit points can also be increased to 130 by adding 10 rows in the horizontal direction while reducing the spacing between the .

Further, plate-like metal pieces 10, 11, 12, 13, 14, 15, 16 which are the main bodies of the hardness reference pieces 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I, 1J described above. , 17, 18, and 19, it is recommended to use an aluminum alloy that achieves the desired surface hardness while appropriately adjusting the type and proportion of the metal contained and the treatment method, and has a lighter specific gravity than iron. It is suitable as a hardness reference piece in that it is excellent in corrosion resistance.

Furthermore, in the above-described embodiments, the display method of the guide patterns 100, 110, 120, 130, 140, 150, 160, 170, 180, 190 is illustrated by printing, but it does not affect the test performance. As far as possible, other methods such as transfer or stamping, machine engraving or laser engraving are also possible. In addition, in the above description, the case of performing the Brinell hardness test according to JIS was exemplified, but the present invention is the same as described above in other standards such as ISO and other test methods such as Rockwell hardness test. The action and effect of is expected.

As described above, with regard to the hardness reference piece, the present invention has made it possible to efficiently use the test surface while properly securing the intervals between the indentations without excessively increasing the labor and cost.

1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I, 1J hardness reference pieces 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 metal pieces 10a, 11a, 12a, 13a, 14a, 15a, 16a, 17a, 18a, 19a test surface, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190 guide pattern, 181, 182, 191 circle, 192 cross

Claims (1)

On the flat test surface on which the indentation is formed by pressing the indenter of the hardness tester, the points of the indenter are hit so that all the formed indentations are aligned with adjacent ones at intervals of a predetermined width or more. A hardness reference piece on which a guide pattern is displayed to serve as a visual guide when determining a position, wherein the guide pattern is a diagram of a combination of lines, and the center of the portion indicating the hitting position is at least the above. It is separated from the edge of the test surface by a predetermined distance or more, and the guide pattern is a plurality of curved circles having a diameter equivalent to the distance to be secured between the adjacent indentations. A hardness reference piece characterized in that it has a circular pattern that is uniformly arranged, and the center of the circle is the center position of the hitting point.

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