JP2008180669A - Hardness testing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hardness testing machine capable of forming indentations having suitable size without having to form trial indentations (preliminary test) to samples having unknown hardness. <P>SOLUTION: An indenting depth measuring means (indentor axial displacement detection part 20) measures an indenting depth when an indentor 1 is pressed into the surface of a sample when an indentation is formed by a test force provided by a test force providing means (a force motor 10 and a force motor 30). On the basis of the test force provided by the test force providing means and the indenting depth measured by the indenting depth measuring means, a measuring means (a CPU 201 and a setting program 203b) sets a maximum test force in such a way that the size of the indentation may have a previously set size estimated on the basis of the relation between the geometric shape of the indentor 1 and the indenting depth of the indentor 1. A control means (the CPU 201 and a control program 203d) controls the test force providing means as to provide a maximum test force set by the setting means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hardness tester.

Conventionally, a hardness tester that evaluates and measures the hardness of a sample based on applying a load to the surface of the sample by an indenter and forming a dent is used. It is necessary to determine the test force so that the indentation has an appropriate size.
By the way, it is not difficult for a user who routinely performs a hardness test on the same type of sample to estimate the hardness of the sample based on the test. There is known a hardness tester that selects and calculates a magnification of an objective lens used for observation and a test force necessary for formation of a dent by simply inputting the length (see Patent Document 1).
JP 2005-114613 A

  However, in the case of the above-described prior art, for the types of samples that have been tested in the past, from the experience by the user, a hardness test can be suitably performed, but the user has not performed the test, When testing a sample of unknown hardness, it is difficult to know how much load should be applied to the sample surface by the indenter to form an optimally dent. Test).

  The subject of this invention is providing the hardness tester which can form the hollow of a suitable magnitude | size, without throwing away with respect to the sample whose hardness is unknown (preliminary test).

In order to solve the above problems, the invention described in claim 1
In a hardness tester that measures hardness based on the size of a depression formed by pushing an indenter into the sample surface,
A test force applying means for applying a test force to the indenter;
An indentation depth measuring means for measuring an indentation depth when the indenter is indented into the sample surface at the time of forming a recess by the test force applied by the test force applying means;
Estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter by the test force imparted by the test force imparting means and the indentation depth measured by the indentation depth measuring means at the time of forming the recess. Setting means for setting a maximum test force so that the indented dimension to be a preset indented dimension;
Control means for controlling the test force applying means to apply the maximum test force set by the setting means;
It is characterized by providing.

The invention described in claim 2
The hardness tester according to claim 1,
A recess size input means for inputting the recess size desired by the user;
Indentation depth calculating means for calculating the indentation depth of the indenter, in which the indentation size estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter is the indentation size input by the indentation size input means. And comprising
The setting means sets a test force that is the indentation depth calculated by the indentation depth calculation means.

The invention described in claim 3
In the hardness tester according to claim 2,
An indentation range information input means for inputting information regarding the range of the sample surface into which the indenter is to be pushed;
When the indentation size input by the indentation size input means exceeds the range of the sample surface that pushes in the indenter input by the indentation range information input means, the indentation size is the range of the sample surface into which the indenter is pushed. An indentation size correcting means for correcting the indentation into a predetermined indentation size,
It is characterized by providing.

The invention according to claim 4
In a hardness tester that measures hardness based on the size of a depression formed by pushing an indenter into the sample surface,
An indentation range information input means for inputting information regarding the range of the sample surface into which the indenter is to be pushed;
A test force applying means for applying a test force to the indenter;
An indentation depth measuring means for measuring an indentation depth when the indenter is indented into the sample surface at the time of forming a recess by the test force applied by the test force applying means;
Estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter by the test force imparted by the test force imparting means and the indentation depth measured by the indentation depth measuring means at the time of forming the recess. An indentation depth calculating means for calculating an indentation depth of the indenter that has a maximum in the range of the sample surface inputted by the indentation range information input means;
Setting means for setting a maximum test force to be the indentation depth calculated by the indentation depth calculating means;
Control means for controlling the test force applying means to apply the maximum test force set by the setting means;
It is characterized by providing.

The invention described in claim 5
In the hardness testing machine according to any one of claims 1 to 4,
The control means includes
The time required until the maximum test force set by the setting means is reached after the indenter contacts the sample surface is controlled.

According to the first aspect of the present invention, the test force can be applied to the indenter by the test force applying means, and when the depression is formed by the test force applied by the test force applying means by the indentation depth measuring means, The indentation depth at which the indenter is pushed into the surface of the sample can be measured, and the setting means determines the test force applied by the test force application means and the indentation depth measured by the indentation depth measurement means when forming the recess. The maximum test force can be set so that the indentation size estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter becomes a preset indentation size. Further, it is possible to perform control for applying the maximum test force set by the setting means.
Therefore, it is possible to form a recess with a suitable size without throwing away a sample of unknown hardness (preliminary test), and to shorten the test time.

According to the second aspect of the invention, it is possible to obtain the same effect as the first aspect of the invention, and the user can input the desired indentation size by the indentation size input means. The indentation depth calculating means calculates the indenter indentation depth in which the indentation size estimated from the relationship between the indenter geometry and the indenter indentation depth is the indentation size input by the indentation dimension input means. The setting means can set the test force that is the indentation depth calculated by the indentation depth calculation means.
Accordingly, the hardness can be measured based on the indentation size desired by the user, and a more suitable indentation can be formed, and more suitable measurement can be performed.

According to the third aspect of the invention, it is possible to obtain the same effect as that of the second aspect of the invention, and information on the range of the sample surface into which the indenter is pushed is inputted by the pushing range information input means. If the indentation size input by the indentation size input means exceeds the range of the sample surface into which the indenter input by the indentation range information input means is pushed, the indentation size is pushed by the indentation size correcting means. It can be modified to a predetermined indentation size within the sample surface.
Therefore, even if the location to be tested is a local location and can not be thrown away (preliminary test), it is possible to form a recess of an appropriate size according to the location and hardness. It is possible to suitably prevent a test failure due to a mistake in setting the test force even for a sample of which is unknown.

According to the fourth aspect of the present invention, it is possible to input information regarding the range of the sample surface into which the indenter is pushed in by the indentation range information input unit, and it is possible to apply the test force to the indenter by the test force applying unit. The indentation depth can be measured by the indentation depth measuring means when the indentation is formed by the test force applied by the test force applying means, and the indentation depth can be measured by the indentation depth calculating means. Sometimes the indentation size estimated from the relationship between the indenter geometric shape and the indenter indentation depth is determined by the test force imparted by the test force imparting means and the indentation depth measured by the indentation depth measuring means. The indenter indentation depth that is the maximum within the range of the sample surface input by the information input means can be calculated. Thus, the maximum test force that becomes the indentation depth calculated by the indentation depth calculation means can be set, and the control means performs control to apply the maximum test force set by the setting means to the test force application means. be able to.
Therefore, even if the location to be tested is a local location and can not be thrown away (preliminary test), it is possible to form a recess of an appropriate size according to the location and hardness. It is possible to suitably prevent a test failure due to a mistake in setting the test force even for a sample of which is unknown.

According to the fifth aspect of the present invention, it is of course possible to obtain the same effect as that of any one of the first to fourth aspects of the invention, and the control means causes the indenter to contact the sample surface. The time required to reach the maximum test force set by the setting means can be controlled.
Therefore, by making the indenter indentation speed variable during indenter indentation, the time required to reach the maximum test force can be set to, for example, the time required in accordance with the JIS standard, or the test conditions desired by the user. A hardness test can be performed.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
(First embodiment)
FIG. 1 is an explanatory view showing a state in which the schematic configuration of the hardness tester according to the present embodiment is partially viewed from the side. FIG. 2 is a block diagram showing a main configuration of the hardness tester.
As shown in FIG. 1, the hardness tester 100 includes an indenter shaft unit 110 having an indenter shaft 2 provided at the tip with an indenter 1 for forming a recess in a sample S placed on a sample stage 120. A pressing force applying mechanism 130 for applying a predetermined pressing force to the indenter shaft 2, an input unit 140 for inputting information on the size of the indentation and information on the surface of the sample S into which the indenter 1 is pushed, and the indentation is enlarged. The display unit 150 is displayed. In the hardness tester 100, operation control of each unit is performed by the control unit 200 shown in FIG.

  The indenter shaft unit 110 is provided above the sample stage 120. The support springs 3 and 3 as elastic support members provided on the tester main body 101 and the support springs 3 and 3 are elastic on the upper end side and the lower end side, respectively. The indenter shaft 2 supported in force, the force motor 10 that applies a predetermined force in the axial direction to the indenter shaft 2 by moving the indenter shaft 2 in the axial direction, and the displacement amount of the indenter shaft 2 is detected. The indenter shaft displacement detector 20 and the like.

The indenter 1 is an indenter used for a hardness test by forming a recess, such as Vickers, Knoop indenter, Brinell, and the like.

  Each of the support springs 3 and 3 is a leaf spring that is fixed to the test machine main body 101 and extends from the test machine main body 101 in a substantially horizontal direction, and the other ends are respectively the upper end side of the indenter shaft 2. Connected to the lower end side, the indenter shaft 2 is elastically supported perpendicular to the sample stage 120. The support spring 3 is bent and deformed so that the indenter shaft 2 maintains a vertical posture with respect to the sample stage 120 when the indenter shaft 2 is moved in the vertical direction by a force motor 10 described later.

The force motor 10 is composed of a magnetic circuit constituent part 12 and a drive coil part 13 provided on the indenter shaft 2 side. The force motor 10 generates a force in the magnetic circuit configuration unit 12 by electromagnetic induction between a magnetic field generated by a magnet in a gap and a current flowing in a drive coil unit 13 installed in the gap. The force motor 10 uses the force as a driving force, moves the indenter shaft 2 in the axial direction, and applies a predetermined test force to the sample S via the indenter 1 provided on the indenter shaft 2.
In other words, the force motor 10 generates an arbitrary driving force according to the amount of current supplied to the driving coil unit 13 of the force motor 10, and moves the indenter shaft 2 based on the driving force to cause various changes in the sample S. Test force can be applied. The force motor 10 can output a stepless driving force and load the sample S with a stepless test force by adjusting the amount of current flowing through the drive coil unit 13 steplessly.
The current supplied to the drive coil unit 13 of the force motor 10 is controlled by the control unit 200 described later. The force motor 10 generates a driving force based on a predetermined amount of current (or current direction) according to a predetermined test force, and moves the indenter shaft 2 to load the sample S with a predetermined test force. To do.
Thereby, the force motor 10 functions as a test force application unit.

The indenter shaft displacement detector 20 includes, for example, a scale 21 provided with a scale at a predetermined interval, and a linear encoder 22 that optically reads the scale of the scale 21. 2 detects a displacement amount (for example, an intrusion amount when the indenter 1 is pushed into the sample S) when the recess 2 is formed in the sample S, and sends an indenter shaft displacement signal to the control unit 200 based on the detected displacement amount. Output.
Thereby, the indenter shaft displacement detector 20 functions as a push-in depth measuring unit.

  The pressing force applying mechanism unit 130 includes a control lever 50 provided above the indenter shaft unit 110, a force motor 30 that applies an acting force to the control lever 50, and the like.

  The control lever 50 is pivotally supported at a substantially central portion by a rotation shaft 51 so as to be rotatable on a tester main body (not shown). A force motor 30 is attached to one end 50 a of the control lever 50. The other end 50b of the control lever 50 extends above the indenter shaft unit 110 from the rotation shaft 51 and is located above the indenter shaft 2. The other end 50b has an indenter shaft of the indenter shaft unit 110. 2 is provided with a pressing portion 52 for pressing down the upper end portion 2a of the two.

The force motor 30 uses, as a driving force, a force generated by electromagnetic induction between a magnetic field generated by the magnet in the gap and a current flowing in the driving coil unit 33 installed in the gap in the magnetic circuit configuration unit 32. The load shaft 31 is moved in the axial direction by the force, an acting force is applied to the one end portion 50a of the control lever 50, and the control lever 50 is rotated. And the force motor 30 inclines the other end part 50b of the control lever 50 below, and pushes down the indenter axis | shaft 2 to the axial direction with the press part 52 with which the other end part 50b was equipped.
Thereby, the force motor 30 functions as a test force application unit.

The input unit 140 includes, for example, a cursor key, a character / number key, various function keys, and the like, and outputs a pressing signal accompanying a user key operation to the control unit 200. The input unit 140 may include other input devices such as a pointing device such as a mouse or a touch panel as necessary. It should be noted that the input unit 140 according to the present invention is used when inputting, for example, the length data of the diagonal of the recess as the recess size desired by the user. Thereby, the input part 140 functions as a hollow dimension input means.
In addition, for example, a cursor that can be moved by the operation of the input unit 140 is displayed together with an image of the surface of the sample S that pushes the indenter 1 on the display unit 150 that will be described later. Used when specifying. Thereby, the input unit 140 functions as a push-in range information input unit.

  The display unit 150 includes, for example, a liquid crystal monitor, and the display unit 150 according to the present invention displays a captured image of the dent. Further, the display unit 150 displays, for example, a movable cursor used when designating a range of the surface of the sample S into which the indenter 1 is pushed together with an image of the surface of the sample S into which the indenter 1 is pushed. Thereby, the display part 150 functions as a pushing range information input means.

  The control unit 200 includes a CPU (Central Processing Unit) 201, a RAM (Random Access Memory) 202, a storage unit 203, and the like, and a predetermined program stored in the storage unit 203 is executed to execute a predetermined program. It has a function of controlling the operation of each part for forming a recess based on a predetermined operating condition (operating condition for each hardness test) set in advance for performing the hardness test.

  The CPU 201 controls the entire hardness tester 100 by reading a processing program or the like stored in the storage unit 203, developing it in the RAM 202, and executing it.

  The RAM 202 expands the processing program executed by the CPU 201 in the program storage area in the RAM 202, and stores input data and a processing result generated when the processing program is executed in the data storage area.

  The storage unit 203 has, for example, a recording medium (not shown) in which programs, data, and the like are stored in advance, and this recording medium is configured by, for example, a semiconductor memory. The storage unit 203 also stores various data, various processing programs, data processed by the execution of these programs, and the like for realizing a function for the CPU 201 to control the entire hardness tester 100. More specifically, the storage unit 203 stores, for example, as shown in FIG. 2, an indentation depth calculation program 203a, a setting program 203b, an indentation size correction program 203c, a control program 203d, and the like.

The indentation depth calculation program 203a causes the CPU 201 to set the indentation size estimated from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 to the indentation size desired by the user input from the input unit 140. This is a program for realizing the function of calculating the indentation depth of the indenter 1.
That is, for example, as shown in FIG. 3, in the case of an indenter that is a regular quadrangular pyramid with a facing angle of 136 ° used in the Vickers hardness tester, the CPU 201 executes the indentation depth calculation program 203 a to obtain a user desired When the length d of the bottom diagonal line is input by the input unit 140 as the indentation dimension, the corresponding indentation depth h is calculated.
The CPU 201 functions as an indentation depth calculation unit by executing the indentation depth calculation program 203a.

The setting program 203b causes the CPU 201 to determine the geometric shape of the indenter 1 based on the test force applied by the force motor 10 and the force motor 30 and the indentation depth measured by the indenter shaft displacement detection unit 20 when the recess is formed. This is a program for realizing a function of setting a maximum test force at which the indentation size estimated from the relationship with the indentation depth of the indenter 1 becomes a preset indentation size.
Specifically, for example, as shown in FIG. 4, when the CPU 201 executes the setting program 203 b to gradually increase the test force by the force motor 10 and the force motor 30, the indenter shaft displacement detection unit 20 From the relationship between the indentation depth during measurement and the test force applied by the force motor 10 and the force motor 30, the test force when the CPU 201 reaches the indentation depth calculated by executing the indentation depth calculation program 203a. Predict and set the test force as the maximum test force.
The CPU 201 functions as a setting unit by executing the setting program 203a.

The indentation size correction program 203c is a program that realizes a function of correcting to a predetermined indentation size when the indentation size input by the input unit 140 is inappropriate.
Specifically, the CPU 201 executes the indentation size correction program 203c so that the user-desired indentation size input by the input unit 140 relates to the range of the surface of the sample S into which the indenter 1 input by the input unit 140 is pushed. Based on the information, when the range of the surface of the sample S into which the indenter 1 is pushed is exceeded, the indentation size is corrected to a predetermined indentation within the range of the surface of the sample S into which the indenter 1 is pushed.
More specifically, for example, the user inputs a diagonal length of 0.1 mm as a desired indentation size via the input unit 140, and the surface area 0 of the sample S as information regarding the surface of the sample S into which the indenter 1 is pushed by the input unit 140. When .08 × 0.06 mm ² is input, under such test conditions, the size of the recess formed on the surface of the sample S protrudes the portion to be tested, so the CPU 201 executes the recess size correction program 203c. By doing so, for example, the maximum indentation size that falls within the surface area of the sample S is calculated, and the indentation size is corrected by multiplying the maximum indentation size by a predetermined coefficient n (n <1).
The CPU 201 functions as a recess dimension correcting unit by executing the recess dimension correcting program 203c.

The control program 203d is a program that realizes a function of performing control to apply a predetermined test force to the force motor 10 and the force motor 30.
Specifically, the CPU 201 executes the control program 203d to cause the force motor 10 and the force motor 30 to apply the maximum test force set by the CPU 201 executing the setting program 203b and to form a recess. At that time, the indentation depth measured by the indenter shaft displacement detector 20 is used to predict the time until the CPU 201 reaches the indentation depth calculated by executing the indentation depth calculation program 203a. The force application speed of the force motor 10 and the force motor 30 is controlled so that the maximum test force is reached within a predetermined time after the surface of the sample S contacts the surface of the sample S.
More specifically, for example, when performing a Vickers hardness test (JIS Z2244) compliant with the JIS standard, when the maximum test force set by the CPU 71 executing the setting program 73b exceeds 29.4 N, The time required to reach the maximum test force is 2 to 8 seconds. On the other hand, when the maximum test force is 29.42 N or less, the time required to reach the maximum test force is 10 seconds or less. In addition, the control is performed by varying the application speed of the test force by the force motor 10 and the force motor 30.
The CPU 201 functions as a control unit by executing the control program 203d.

Next, a dent forming method in a hardness test using the hardness tester 100 in the first embodiment will be described.
First, the indenter 1 is attached to the indenter shaft 2, the sample S is placed on the sample stage 120, and the sample stage 120 is adjusted.
Next, the user inputs a desired indentation size into the input unit 140. In addition, the user inputs information regarding the range of the surface of the sample S into which the indenter 1 is pushed into the input unit 140. At this time, the CPU 201 executes the indentation size correction program 203c, so that the indentation size input by the input unit 140 exceeds the range of the surface of the sample S into which the indenter 1 input by the input unit 140 is pushed. The indentation size is corrected to a predetermined indentation within the range of the surface of the sample S into which the indenter 1 is pushed.
Next, the CPU 201 executes the indentation depth calculation program 203 a, so that the indentation size estimated from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 is the indentation size input by the input unit 140. The indentation depth of the indenter 1 is calculated.
Next, when the indentation depth is calculated, the CPU 201 executes the setting program 203b to measure the test force applied by the force motor 10 and the force motor 30 and the indenter shaft displacement detection unit 20 when the recess is formed. The maximum test force is set so that the indentation size estimated from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 becomes the indentation size input by the input unit 140 based on the indentation depth. .
Next, the CPU 201 executes a control program 203d to perform control for applying the maximum test force set by the execution of the setting program 203b, and sets the indenter 1 within a predetermined time after contacting the surface of the sample S. The test force by the force motor 10 and the force motor 30 is controlled so as to reach the maximum test force set by the execution of the program 203b. Then, the indenter 1 attached to the tip of the indenter shaft 2 is pushed into the sample S with the set maximum test force, and a recess is formed in the sample S.

According to the hardness tester 100 according to the first embodiment of the present invention, a test force can be applied to the indenter 1 by the force motor 10 and the force motor 30, and the force is detected by the indenter shaft displacement detection unit 20. When the indentation is formed by the test force applied by the motor 10 and the force motor 30, the indentation depth by which the indenter 1 is pushed into the surface of the sample S can be measured, and the CPU 201 executes the setting program 203b. The relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 based on the test force applied by the force motor 10 and the force motor 30 and the indentation depth measured by the indenter shaft displacement detection unit 20 when the recess is formed. Set the maximum test force so that the indentation size estimated from the above is the preset indentation size Bets can be, by executing the control program 203d, the force motor 10, and the force motor 30 can be controlled to impart maximum test force set by executing the setting program 203b.
Therefore, it is possible to form a recess with a suitable size without throwing away a sample of unknown hardness (preliminary test), and to shorten the test time.
In addition, the user can input a desired indentation size by the input unit 140, and the CPU 201 executes the indentation depth calculation program 203a, whereby the geometric shape of the indenter 1 and the indentation depth of the indenter 1 are determined. The indentation depth of the indenter 1 in which the indentation size estimated from the relationship becomes the indentation size input by the input unit 140 can be calculated, and is calculated by executing the indentation depth calculation program 203a by executing the setting program 203b. It is possible to set a test force that results in the indentation depth.
Accordingly, the hardness can be measured based on the indentation size desired by the user, and a more suitable indentation can be formed, and more suitable measurement can be performed.
In addition, information regarding the range of the surface of the sample S into which the indenter 1 is pushed can be inputted by the input unit 140, and the indentation size inputted by the input unit 140 is the surface of the sample S into which the indenter 1 inputted by the input unit 140 is pushed. When the above range is exceeded, the CPU 201 can execute the indentation size correction program 203c to correct the indentation size to a predetermined indentation size within the range of the surface of the sample S into which the indenter 1 is pushed.
Therefore, even if the location to be tested is a local location and can not be thrown away (preliminary test), it is possible to form a recess of an appropriate size according to the location and hardness. It is possible to suitably prevent a test failure due to a mistake in setting the test force even for a sample of which is unknown.
Further, the CPU 201 can control the time required until the maximum test force set by the execution of the setting program 203b after the indenter 1 contacts the surface of the sample S by executing the control program 203d.
Therefore, by making the indenter indentation speed variable during indenter indentation, the time required to reach the maximum test force can be changed to the required time conforming to the JIS standard, or hardened according to the test conditions desired by the user. Can be tested.

(Second Embodiment)
Next, a second embodiment of the hardness tester according to the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same part as 1st Embodiment, and only a different part is demonstrated.

  As shown in FIG. 5, the control unit 300 includes a CPU (Central Processing Unit) 201, a RAM (Random Access Memory) 202, a storage unit 303, and the like, and a predetermined program stored in the storage unit 303 is executed. By doing so, it has a function of controlling the operation of each part for forming a recess based on a predetermined operation condition (operation condition for each hardness test) set in advance to perform a predetermined hardness test.

  The storage unit 303 has, for example, a recording medium (not shown) in which programs, data, and the like are stored in advance, and this recording medium is configured by, for example, a semiconductor memory. In addition, the storage unit 303 stores various data, various processing programs, data processed by executing these programs, and the like for realizing the function of the CPU 201 controlling the entire hardness tester 100. More specifically, the storage unit 303 stores, for example, a push-in depth calculation program 303a, a setting program 303b, and a control program 303c as shown in FIG.

The indentation depth calculation program 303a has the indentation size estimated from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 input to the CPU 201 on the surface of the sample S into which the indenter 1 is input. This is a program for realizing the function of calculating the indentation depth of the indenter 1 that is the maximum in the range.
Specifically, for example, as shown in FIG. 3, in the case of an indenter that is a regular quadrangular pyramid having a facing angle of 136 ° used in a Vickers hardness tester, range information of the surface of the sample S into which the indenter 1 is pushed is input by the input unit 140. When the depression is formed, the CPU 201 executes the indentation depth calculation program 303a to thereby estimate the indentation dimension (diagonal length d) from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1. ) Calculates the indentation depth h of the indenter 1 that is the maximum in the range based on the range information on the surface of the sample S into which the indenter 1 is input by the input unit 140.
The CPU 201 functions as an indentation depth calculation unit by executing the indentation depth calculation program 303a.

The setting program 303b is a program that causes the CPU 201 to realize a function of setting the maximum test force that is the indentation depth calculated by executing the indentation depth calculation program 303a.
Specifically, for example, as illustrated in FIG. 4, when the CPU 201 executes the setting program 303 b to gradually increase the test force by the force motor 10 and the force motor 30, the indenter shaft displacement detection unit 20 Based on the relationship between the indentation depth during measurement and the test force applied by the force motor 10 and the force motor 30, the test force when the CPU 201 reaches the indentation depth calculated by executing the indentation depth calculation program 303a. Predict and set the test force as the maximum test force.
The CPU 201 functions as a setting unit by executing the setting program 303b.

The control program 303c is a program that realizes a function of performing control to apply a predetermined test force to the force motor 10 and the force motor 30.
Specifically, the CPU 201 executes the control program 303c, thereby giving the force motor 10 and the force motor 30 the maximum test force set by the CPU 201 executing the setting program 303b, and forming a dent. At that time, the indentation depth measured by the indenter shaft displacement detector 20 is used to predict the time until the CPU 201 reaches the indentation depth calculated by executing the indentation depth calculation program 303a. The force application speed of the force motor 10 and the force motor 30 is controlled so that the maximum test force is reached within a predetermined time after the surface of the sample S contacts the surface of the sample S.
More specifically, for example, when performing a Vickers hardness test (JIS Z2244) compliant with the JIS standard, when the maximum test force set by the CPU 201 executing the setting program 303b exceeds 29.4N, The time required to reach the maximum test force is 2 to 8 seconds. On the other hand, when the maximum test force is 29.42 N or less, the time required to reach the maximum test force is 10 seconds or less. In addition, the control is performed by varying the application speed of the test force by the force motor 10 and the force motor 30.
The CPU 201 functions as a control unit by executing the control program 303c.

Next, a dent forming method in a hardness test using the hardness tester 100 according to the second embodiment will be described.
First, the indenter 1 is attached to the indenter shaft 2, the sample S is placed on the sample stage 120, and the sample stage 120 is adjusted.
Next, the user inputs information regarding the range of the surface of the sample S into which the indenter 1 is pushed into the input unit 140.
Next, the CPU 201 executes the indentation depth calculation program 303a, so that the indenter 1 estimated from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 is input by the input unit 140. The indentation depth of the indenter 1 that is the maximum in the range of the surface of the sample S into which is pushed is calculated.
Next, when the indentation depth is calculated, the CPU 201 executes the setting program 303b to measure the test force applied by the force motor 10 and the force motor 30 and the indenter shaft displacement detection unit 20 when the recess is formed. The maximum test force is set so that the indentation size estimated from the relationship between the geometric shape of the indenter 1 and the indentation depth of the indenter 1 becomes the indentation size input by the input unit 140 based on the indentation depth. .
Next, the CPU 201 executes control to execute the control program 303c so that the maximum test force set by the execution of the setting program 303b is applied, and is set within a predetermined time after the indenter 1 contacts the surface of the sample S. The test force by the force motor 10 and the force motor 30 is controlled so as to reach the maximum test force set by the execution of the program 303b. Then, the indenter 1 attached to the tip of the indenter shaft 2 is pushed into the sample S with the set maximum test force, and a recess is formed in the sample S.

According to the hardness tester 1 according to the second embodiment of the present invention, information regarding the range of the surface of the sample S into which the indenter 1 is pushed can be input by the input unit 140, and the force motor 10 and the force motor 30. Thus, a test force can be applied to the indenter 1, and the indenter 1 is pushed into the surface of the sample S by the indenter shaft displacement detection unit 20 when a depression is formed by the test force applied by the force motor 10 and the force motor 30. The indentation depth can be measured, and when the CPU 201 executes the indentation depth calculation program 303a, the test force applied by the force motor 10 and the force motor 30 and the indenter shaft displacement detection unit when the depression is formed. 20 and the indentation depth measured by the indenter 20 and the indenter indentation depth. The indentation depth of the indenter 1 at which the indentation size estimated from the relationship of FIG. 5 becomes the maximum in the range of the surface of the sample S input by the input unit 140 can be calculated, and the indentation depth can be calculated by executing the setting program 303b. The maximum test force that is the indentation depth calculated by executing the calculation program 303a can be set. By executing the control program 303c, the force is set in the force motor 10 and the force motor 30 by executing the setting program 303b. It is possible to perform control to give the maximum test force.
Therefore, even if the location to be tested is a local location and can not be thrown away (preliminary test), it is possible to form a recess of an appropriate size according to the location and hardness. It is possible to suitably prevent a test failure due to a mistake in setting the test force even for a sample of which is unknown.
Further, by executing the control program 303c, the CPU 201 can control the time required for the indenter 1 to contact the surface of the sample S and reach the maximum test force set by executing the setting program 303b.
Therefore, by making the indenter indentation speed variable during indenter indentation, the time required to reach the maximum test force can be changed to the required time conforming to the JIS standard, or hardened according to the test conditions desired by the user. Can be tested.

  The present invention is not limited to the above embodiment. For example, the hardness tester may be a dent observation type hardness tester, and can be used for a Vickers hardness tester, a Brinell hardness tester, a Knoop hardness tester, and the like. In addition, in the embodiment described above, the indentation range information input means is displayed on the display unit 150 by the input unit 140 based on the image data of the surface of the sample S into which the indenter 1 is to be pushed. Although the configuration is such that the indentation range information on the surface of the sample S is input with the displayed cursor, for example, the control unit 200 includes image processing means and is based on the image data on the surface of the sample S into which the indenter 1 is to be pushed. The edge of the sample S may be discriminated and the push-in range may be automatically specified, or a combination of these may be used. In addition, the present invention can be freely changed and improved without departing from the gist of the invention.

1 is a schematic sectional view of a hardness tester according to the present invention. It is a block diagram showing a schematic structure of a hardness tester in a 1st embodiment concerning the present invention. It is a figure which shows the relationship between the geometric shape of an indenter and the indentation depth of the indenter in the hardness tester which concerns on this invention. It is a figure which shows the relationship between the indentation depth of the indenter at the time of hollow formation in the hardness tester based on this invention, and test force. It is a block diagram which shows schematic structure of the hardness tester in 2nd Embodiment which concerns on this invention.

Explanation of symbols

100 Hardness tester 1 Indenter 10 Force motor (Test force applying means)
20 Indenter shaft displacement detector (pushing depth measuring means)
30 force motor (test force application means)
140 Input section (recess dimension input means, push range information input means)
150 Display (push-in range information input means)
200 control unit 201 CPU (push-in depth calculating means, setting means, indentation size correcting means, control means)
203 storage unit 203a indentation depth calculation program (indentation depth calculation means)
203b Setting program (setting means)
203c Recess size correction program (recess size correction means)
203d Control program (control means)
300 control unit 303 storage unit 303a indentation depth calculation program (indentation depth calculation means)
303b Setting program (setting means)
303c Control program (control means)
S sample

Claims (5)

In a hardness tester that measures hardness based on the size of a depression formed by pushing an indenter into the sample surface,
A test force applying means for applying a test force to the indenter;
An indentation depth measuring means for measuring an indentation depth when the indenter is indented into the sample surface at the time of forming a recess by the test force applied by the test force applying means;
Estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter by the test force imparted by the test force imparting means and the indentation depth measured by the indentation depth measuring means at the time of forming the recess. Setting means for setting a maximum test force so that the indented dimension to be a preset indented dimension;
Control means for controlling the test force applying means to apply the maximum test force set by the setting means;
A hardness tester comprising: A recess size input means for inputting the recess size desired by the user;
Indentation depth calculating means for calculating the indentation depth of the indenter, in which the indentation size estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter is the indentation size input by the indentation size input means. And comprising
The hardness tester according to claim 1, wherein the setting means sets a maximum test force that is the indentation depth calculated by the indentation depth calculation means. An indentation range information input means for inputting information regarding the range of the sample surface into which the indenter is to be pushed;
When the indentation size input by the indentation size input means exceeds the range of the sample surface that pushes in the indenter input by the indentation range information input means, the indentation size is the range of the sample surface into which the indenter is pushed. An indentation size correcting means for correcting the indentation into a predetermined indentation size,
The hardness tester according to claim 2, comprising: In a hardness tester that measures hardness based on the size of a depression formed by pushing an indenter into the sample surface,
An indentation range information input means for inputting information regarding the range of the sample surface into which the indenter is to be pushed;
A test force applying means for applying a test force to the indenter;
An indentation depth measuring means for measuring an indentation depth when the indenter is indented into the sample surface at the time of forming a recess by the test force applied by the test force applying means;
Estimated from the relationship between the geometric shape of the indenter and the indentation depth of the indenter by the test force imparted by the test force imparting means and the indentation depth measured by the indentation depth measuring means at the time of forming the recess. An indentation depth calculating means for calculating an indentation depth of the indenter that has a maximum in the range of the sample surface inputted by the indentation range information input means;
Setting means for setting a maximum test force to be the indentation depth calculated by the indentation depth calculating means;
Control means for controlling the test force applying means to apply the maximum test force set by the setting means;
A hardness tester comprising: The control means includes
5. The hardness according to claim 1, wherein a time required until the maximum test force set by the setting means is reached after the indenter contacts the sample surface is controlled. testing machine.

Images