JP2006220496A - Hardness testing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hardness testing machine constituted so as to more certainly prevent the shift of an indenter shaft. <P>SOLUTION: The hardness testing machine is equipped with: an indenter; the indenter shaft; a support part for supporting the indenter shaft so as to move the same in its axial direction; and a load applying mechanism part. The support part 6 is constituted of a plurality of return spring 61 and a connecting member 62, and return springs 61 are constituted of the inner leaf spring part fixed to the indenter shaft at its one end part, with the outer leaf string part being fixed to a testing machine body at its one end part and a connection part for connecting the inner leaf spring part and the other end part of the outer leaf string part, while the connection part of a plurality of the return springs 61 is connected to the connection member 62. The support part 6 is constituted so that the outer leaf string part is displaced, so as to negate the movement of the indenter shaft in a direction vertical to the axial direction of the indenter shaft, accompanied by the displacement of the inner leaf spring part at the time of movement of the indenter shaft in its axial direction. The inner leaf spring part and the outer leaf spring part are formed into a shape, preliminarily deformed to an opposite side by the displacement quantity of the connection member 62, due to own weight so as to become vertical with respect to the indenter shaft, when the own weight of the connection member 62 acts. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hardness tester that measures the hardness of a sample by forming a dent on the surface of the sample.

Conventionally, a hardness tester that evaluates and measures the hardness of a sample based on applying a load to the surface of the sample with an indenter and forming a recess has been used (for example, Patent Document 1).
The hardness tester described in Patent Document 1 includes an indenter shaft having an indenter at the tip, a support portion that elastically supports the indenter shaft on the tester body, and a load loading mechanism that moves the indenter shaft in the axial direction. It is provided with a part etc.
The support part is comprised by the connection member etc. which connect two folding springs and two folding springs. The folding spring has a substantially E shape in which three leaf spring pieces are connected at one end (hereinafter referred to as a connecting portion). The open end of the center leaf spring piece (hereinafter referred to as the middle leaf spring portion) of the folding spring is fixed to the indenter shaft, and the leaf spring piece (hereinafter referred to as the outer leaf spring portion) located outside the middle leaf spring portion is opened. The end is fixed to the tester body. Further, the connecting portions are connected by a connecting member so that the two folding springs are arranged vertically along the axial direction of the indenter shaft. When the indenter shaft is pushed by the load loading mechanism and moves downward, the middle leaf spring portion and the outer leaf spring portion bend vertically and the connecting member moves to the indenter shaft side. Axis misalignment is prevented.
JP 2004-205334 A

  However, more strictly, for example, as shown in FIG. 6A, even before the indenter shaft 104 moves in the axial direction, the folding spring 161 is already slightly bent due to its own weight. The connecting member 162 was positioned below the indenter shaft 104. When the indenter shaft 104 is moved downward along the axial direction from the state where the folding spring 161 is already bent, the connecting member 162 is moved downward from the indenter shaft 104 as shown in FIG. For this reason, the outer leaf spring portion 164 tends to bend further, while the middle leaf spring portion 163 is displaced in a direction to cancel the deflection, and the indenter shaft 104 is displaced in the horizontal direction from the axial position before the movement. End up. When the indenter shaft 104 is further moved downward, the middle leaf spring portion 163 is displaced in the direction of bending again. That is, as a result, the axial displacement of the indenter shaft 104 occurs.

  The subject of this invention is providing the hardness tester which prevents the axial deviation of an indenter axis | shaft more reliably.

In order to solve the above problems, the invention according to claim 1 is directed to an indenter shaft having an indenter at a tip portion, a support portion that supports the indenter shaft so as to be movable in the axial direction, and an axial direction relative to the indenter shaft In a hardness tester comprising a load-loading mechanism that loads a predetermined force of
The support portion includes a plurality of elastic members and a connecting member that connects the plurality of elastic members,
The elastic member includes a first elastic portion whose one end is fixed to the indenter shaft, a second elastic portion whose one end is fixed to a tester body of the hardness tester, and the first elasticity. A connecting portion that connects the other end portion of the portion and the other end portion of the second elastic portion,
The connecting member connects the connecting portions of the plurality of elastic members,
In the support portion, the first elastic portion is displaced in the axial direction of the indenter shaft when the load loading mechanism portion applies a predetermined force to the indenter shaft and the indenter shaft moves in the axial direction. The second elastic part is configured to be displaced so as to cancel the movement of the indenter shaft in a direction perpendicular to the axial direction.
The first elastic portion and the second elastic portion are preliminarily opposite to each other by a displacement due to the weight of the connecting member so that the first elastic portion and the second elastic portion are perpendicular to the indenter shaft when the weight of the connecting member acts. It is characterized by being deformed into a shape.

  According to a second aspect of the present invention, in the hardness tester according to the first aspect, the first elastic portion and the second elastic portion are integrally formed from a leaf spring. To do.

  According to the first aspect of the present invention, the first elastic portion and the second elastic portion depend on the weight of the connecting member so as to be perpendicular to the indenter shaft when the weight of the connecting member acts. Since the shape is deformed to the opposite side in advance, when the plurality of elastic members are connected by the connecting members and mounted in the hardness tester, the first elastic portion and the second elastic portion Is perpendicular to the indenter axis. Therefore, when the indenter shaft is moved downward by the load-loading mechanism portion, both the first elastic portion and the second elastic portion can be displaced in the bending direction, so that the first elastic portion and the second elastic portion Is displaced so that the side shapes of the first elastic portion and the second elastic portion are vertically symmetrical, the connecting member is drawn toward the indenter shaft side, and the axial displacement of the indenter shaft is further reduced. It can be surely prevented.

  According to the second aspect of the invention, the same effect as in the first aspect can be obtained, and in particular, the first elastic portion and the second elastic portion are integrally formed from a leaf spring. Therefore, by adjusting the shapes of the first elastic portion and the second elastic portion, adjustment of the spring coefficient of the first elastic portion and the second elastic portion and adjustment of the amount of bending can be easily performed. Can do. For example, by making the shapes of the first elastic part and the second elastic part substantially the same, the spring coefficient and the deflection amount of the first elastic part and the second elastic part can be made substantially the same. .

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
First, the configuration of the hardness tester 1 according to the present invention will be described.

  As shown in FIGS. 1 and 2, a hardness tester 1 according to the present invention includes an indenter mounting portion 3 having an indenter 2 at the tip, and an indenter shaft 4 that holds the indenter 2 via the indenter mounting portion 3. An indenter shaft mounting portion 51 for mounting the indenter shaft 4 to the hardness tester main body 5, a support portion 6 that elastically supports the indenter shaft 4 so as to be movable in the axial direction on the indenter shaft mounting portion 51, and an indenter shaft 4 includes a load loading mechanism unit 7 that applies a predetermined force in the axial direction thereof, a sample stage 8 on which the sample S is placed, and the like.

The indenter mounting portion 3 connects the indenter 2 to the indenter shaft 4 by attaching the indenter 2 to the lower end portion and holding the indenter shaft 4 at the upper end portion.
A stopper 31 is provided on the side surface of the indenter mounting portion 3.
The stopper 31 is formed by integrally forming a substantially cylindrical main body 31a and a spherical portion 31b provided on the upper surface of the main body 31a, and the upper surface of the substantially cylindrical main body 31a has a mortar shape. The spherical portion 31b is located so as to fit in the upper portion of the mortar shape. Moreover, the uppermost part of the spherical part 31b is slightly higher than the upper end part of the main body part 31a.

  The indenter shaft attaching portion 51 attaches the indenter shaft 4 to the hardness tester body 5 by elastically holding the indenter shaft 4 via the support portion 6. Further, the indenter shaft mounting portion 51 has a leaf spring member 51 a fixed to the lower end portion side of the indenter shaft 4 with a bolt B. The leaf spring member 51 a comes into contact with the spherical portion 31 b of the stopper 31 provided in the indenter mounting portion 3 when the indenter shaft 4 is positioned at the uppermost position. Thereby, the zero point position of the indenter shaft 4 in the axial direction is defined. Then, the displacement of the indenter shaft 4 from the zero point position defined here is measured by a displacement meter (not shown), and the displacement of the indenter shaft 4 in the axial direction is measured.

  As shown in FIG. 1, the support portion 6 includes folding springs 61 and 61 as two upper and lower elastic members that elastically connect the indenter shaft mounting portion 51 and the indenter shaft 4 on the upper end side and the lower end side, respectively. The upper and lower folding springs 61, 61 are connected to each other and provided with a connecting member 62 and the like.

  The folding spring 61 is formed of, for example, a metal such as beryllium copper, and as shown in FIG. 3, a middle plate spring portion 63 as a first elastic portion extending leftward in the drawing, Outer leaf spring portions 64 and 64 as second elastic portions extending from the one end portion 641 to the left in the drawing on both sides of the leaf spring portion 63 (upper and lower sides of the middle leaf spring portion 63 in the figure), and the middle plate A connecting portion 65 that connects the other end 632 of the spring portion 63 and the other end portions 642 and 642 of the outer plate spring portions 64 and 64 is provided. The middle leaf spring portion 63, the outer leaf spring portions 64 and 64, and the connection portion 65 are integrally formed from a leaf spring.

Further, the side shape of the folding spring 61 is a shape that is deformed in advance to the opposite side by the amount of displacement due to the weight of the connecting member 62 so as to be perpendicular to the indenter shaft 4 when the weight of the connecting member 62 acts. It is molded into. More specifically, as shown in FIG. 4, the end portions 631 and 641 of the middle leaf spring portion 63 and the outer leaf spring portion 64 are bent and molded so as to protrude downward. Further, the degree of the bending is calculated from the bending curve based on the weight of the connecting member 62.
When the two folding springs 61 formed in this way are connected by the connecting member 62 and mounted on the hardness tester 1, the bending spring 61 is bent as shown in FIGS. The side surface shape of the folding spring 61 is almost straight because the weight of the connecting member 62 is eliminated, and the folding spring 61 is perpendicular to the indenter shaft 4.

  The width of the middle leaf spring portion 63 (length in the vertical direction in the drawing; b) is twice the width of the outer leaf spring portion 64 (length in the vertical direction in the drawing; a) (that is, b = a + a). Is formed. Accordingly, the middle leaf spring portion 63 and the two outer leaf spring portions 64 and 64 have the same length (the length in the left-right direction in the drawing) and the same thickness and substantially the same width. It will have a spring constant.

In the upper folding spring 61 (61a), one end portion 631 of the middle leaf spring portion 63 is fixed to the upper end portion of the indenter shaft 4 by a bolt B via a fixing plate (not shown), and the outer leaf spring portion 64. Is fixed to the upper surface of the indenter shaft mounting portion 51 with a bolt B.
In the lower folding spring 61 (61b), one end portion 631 of the middle leaf spring portion 63 is fixed between the lower end portion of the indenter shaft 4 and the indenter attachment portion 3 via a fixed plate, and the outer leaf spring One end portion 641 of the portion 64 is fixed to the lower surface of the indenter shaft mounting portion 51 with a bolt B.

The upper and lower folding springs 61 and 61 are connected by a connecting member 62.
As shown in FIG. 1, the connecting member 62 has, for example, a substantially U shape in a side view, and a connection portion 65 of the upper folding spring 61 (61 a) is connected to the upper end 62 a of the connecting member 62 with a bolt B. It is fixed by. A connecting portion 65 of the lower folding spring 61 (61 b) is fixed to the lower end portion 62 b of the connecting member 62 with a bolt B. That is, the connecting member 62 connects the upper folding spring 61 (61a) and the lower folding spring 61 (61b).

  In addition, by fixing the connection portion 65 of the folding spring 61 (61a, 61b) to the upper end portion 62a and the lower end portion 62b of the connecting member 62, the other end portion 632 of the middle leaf spring portion 63, the outer leaf spring portion 64, The other end portions 642 and 642 of 64 are connected so as to have the same fulcrum.

By such a folding spring 61, the indenter shaft 4 is attached to the hardness tester body 5 with its axial direction perpendicular to the mounting surface of the sample table 8 and is elastically supported. .
As shown in FIG. 1, the connecting member 62 is arranged in the vertical direction parallel to the axis of the indenter shaft 4.

  As shown in FIG. 5, as the indenter shaft 4 is loaded with a test force and moved in the axial direction, the side plate shapes of the middle leaf spring portion 63 and the outer leaf spring portions 64 and 64 are both linear ( From FIG. 5A, the shape is bent (FIG. 5B). At this time, the middle leaf spring portion 63 and the outer leaf spring portions 64 and 64 are elastically displaced so that the side surface shapes thereof are vertically symmetric. That is, when the indenter shaft 4 moves in the axial direction, the indenter shaft 4 moves in a direction perpendicular to the axial direction when the middle leaf spring portion 63 is displaced in the axial direction of the indenter shaft 4. The outer leaf spring portions 64 and 64 are configured to be displaced so as to cancel each other. Further, when the middle leaf spring portion 63 and the outer leaf spring portions 64 and 64 are bent, one end portions 641 and 641 of the outer leaf spring portions 64 and 64 are connected to the indenter shaft attaching portion 51 of the hardness tester 1 and do not move. Therefore, the connecting member 62 is pulled toward the indenter shaft 4 side. Then, the connecting member 62 is drawn toward the indenter shaft 4 side, so that the axial displacement of the indenter shaft 4 is prevented.

  The load load mechanism unit 7 is configured by, for example, a force motor or the like, and in a magnetic circuit configuration unit (not illustrated) provided in the force motor, a magnetic flux generated by a magnet (not illustrated) and a gap is disposed in the gap. A force generated by electromagnetic induction with a drive current (not shown) supplied to a drive coil (not shown) is used as a drive force, and the load shaft 71 of the load load mechanism unit 7 is moved in the axial direction so that a predetermined force is applied to the indenter shaft 4. It comes to load the power of.

Next, an example of a hardness test in the hardness tester 1 configured as described above will be described in detail.
First, the sample S is mounted on the mounting surface of the sample table 8, and an operation command for the hardness tester 1 to perform a hardness test operation is input by an operation unit (not shown). Based on this operation command, a control unit (not shown) supplies a predetermined drive current to the drive coil of the load load mechanism unit 7 to generate a drive force. When a driving force is generated in the driving coil, the load shaft 71 presses the indenter shaft 4 in the axial direction by the driving force and moves it.

  When the load loading mechanism 7 applies a test force to the indenter shaft 4, the indenter shaft 4 moves toward the sample S. As the indenter shaft 4 moves toward the sample S, the middle leaf spring portion 63 whose one end is fixed to the indenter shaft 4 is elastically displaced, and its side surface shape is bent from a linear shape (FIG. 5A). It becomes a bent shape (FIG. 5B). Similarly, the outer leaf spring portions 64 and 64 are also elastically displaced, and the side surface shape is bent from the linear shape. At this time, the middle leaf spring portion 63 and the outer leaf spring portions 64 and 64 are elastically displaced so that the side surface shapes are vertically symmetric. Further, the middle plate spring portion 63 and the outer plate spring portions 64 and 64 are bent, whereby the connecting member 62 is drawn toward the indenter shaft 4 side. Then, the connecting member 62 is drawn toward the indenter shaft 4 side, so that the axial displacement of the indenter shaft 4 is prevented.

  The indenter shaft 4 moves downward along the axial direction while elastically displacing the folding spring 61, and pushes the indenter 2 into the surface of the sample S with a predetermined force to form a recess. Based on the indentation formed on the sample S by the indenter 2 as described above, a hardness measurement test of the sample S, for example, a microhardness test is performed.

  According to the hardness tester 1 according to the present invention described above, the middle leaf spring portion 63 and the outer leaf spring portion 64 are perpendicular to the indenter shaft 4 when the weight of the connecting member 62 acts. As described above, since the displacement due to the weight of the connecting member 62 is deformed in advance to the opposite side, when the plurality of folding springs 61 are connected by the connecting member 62 and mounted in the hardness tester 1. In addition, the middle leaf spring portion 63 and the outer leaf spring portions 64 and 64 are perpendicular to the indenter shaft 4. Therefore, when the indenter shaft 4 is moved downward by the load applying mechanism 7, the middle leaf spring 63 and the outer leaf springs 64 and 64 can be displaced in the direction in which they are bent. 63 and the outer leaf spring portions 64 and 64 are displaced so that the side shapes of the middle leaf spring portion 63 and the outer leaf spring portions 64 and 64 are vertically symmetrical, and the connecting member 62 is moved to the indenter shaft 4 side. It is attracted and the axial displacement of the indenter shaft 4 can be prevented more reliably.

  Further, since the middle leaf spring portion 63 and the outer leaf spring portion 64 are integrally formed from a leaf spring, the middle leaf spring portion can be adjusted by adjusting the shapes of the middle leaf spring portion 63 and the outer leaf spring portion 64. Adjustment of the spring coefficient of 63 and the outer leaf | plate spring part 64 and adjustment of bending amount can be performed easily. For example, by making the shapes of the middle leaf spring portion 63 and the outer leaf spring portion 64 substantially the same, the spring coefficient and the deflection amount of the middle leaf spring portion 63 and the outer leaf spring portion 64 can be made substantially the same. .

  In addition, in this embodiment, although the support part 6 was provided with the two upper and lower folding springs 61, two or more may be provided.

It is a side view which shows the hardness tester principal part which concerns on this invention. It is a perspective view which shows the hardness tester principal part which concerns on this invention. It is a top view in the III-III line of the principal part of the hardness tester of FIG. It is a side view of the support part before mounting | wearing with the hardness tester which concerns on this invention. It is a figure explaining the mode of the elastic displacement of the return spring in the hardness test with the hardness tester concerning the present invention. It is a figure explaining the mode of the elastic displacement of the return spring in the hardness test with the conventional hardness tester.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hardness testing machine 2 Indenter 4 Indenter shaft 6 Support part 61 Folding spring (elastic member)
62 Connecting member 63 Middle leaf spring portion (first elastic portion)
64 Outer leaf spring part (second elastic part)
65 Connection 7 Load-loading mechanism

Claims (2)

An indenter shaft having an indenter at the tip;
A support portion for supporting the indenter shaft so as to be movable in the axial direction;
A load-loading mechanism that applies a predetermined axial force to the indenter shaft;
In a hardness tester comprising:
The support portion includes a plurality of elastic members and a connecting member that connects the plurality of elastic members,
The elastic member is
A first elastic portion having one end fixed to the indenter shaft;
A second elastic portion having one end fixed to the testing machine body of the hardness testing machine;
A connecting portion that connects the other end of the first elastic portion and the other end of the second elastic portion;
With
The connecting member connects the connecting portions of the plurality of elastic members,
In the support portion, the first elastic portion is displaced in the axial direction of the indenter shaft when the load loading mechanism portion applies a predetermined force to the indenter shaft and the indenter shaft moves in the axial direction. The second elastic portion is configured to be displaced so as to cancel the movement of the indenter shaft in a direction perpendicular to the axial direction.
The first elastic portion and the second elastic portion are preliminarily opposite to each other by a displacement due to the weight of the connecting member so that the first elastic portion and the second elastic portion are perpendicular to the indenter shaft when the weight of the connecting member acts. A hardness tester characterized by having a deformed shape.   The hardness tester according to claim 1, wherein the first elastic part and the second elastic part are integrally formed from a leaf spring.

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