JP2000097830A - Displacement calibration jig for instrumentated impact test device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To calibrate a potentiometer simply and highly accurately by measuring a horizontal displacement of a hammer after being moved in the impact direction from a free suspended position, by a measuring apparatus having a probe abutting on an impact edge of the hammer. SOLUTION: A hammer 8 is placed at a free suspended position, and a holder 48 of a displacement calibration jig 46 is mounted on a test piece support stand 14. A probe of a micrometer head 64, a spindle 66, is allowed to abut on an impact edge 10 of the hammer 8 in this state, and a scale value read at that time is set as a reference value. Thereafter, the spindle 66 is retreated in the impact direction of the hammer 8 from the projecting position of the reference value as much as a prescribed length. In this sate, the hammer 8 is moved in the impact direction from the free suspended position, and the impact edge 10 is allowed to abut on the spindle 66 head. In this case, the horizontal position of the hammer 8 can be set simply and optionally only by adjusting the position of the spindle 66, and a potentiometer is adjusted and calibrated, based on a potentiometer output and a retreated length of the spindle 66.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instrumented impact test apparatus such as an instrumented Charpy impact tester or an instrumented Izod impact tester. And a displacement calibration jig used for calibrating the potentiometer when measuring the rotation angle with the potentiometer.

[0002]

[Related Background Art] In this type of impact test apparatus,
The calibration of the potentiometer is performed in the following procedure.
First, as shown in FIG.
The test piece b is placed on the test piece b, and an impact blade of a hammer (not shown) of the test piece b is brought into contact with the test piece b. In this state, the output from the potentiometer is read, and it is confirmed whether or not the output value matches a reference value (for example, zero).

[0003] Thereafter, a block gauge c indicated by a two-dot chain line is placed on the test piece support table a and is brought into close contact with the test piece b.
In this state, the impact blade of the hammer is brought into contact with the block gauge c, the output of the potentiometer at this time is read, and it is checked whether or not the output value matches the horizontal displacement of the hammer determined by the block gauge c. If not, adjust the potentiometer output and perform its calibration.

[0004]

The above-mentioned calibration is performed on the test piece a.
Since the block gauge c is used and the potentiometer is calibrated at an arbitrary horizontal displacement of the hammer, the combination of the block gauges c becomes complicated, and the calibration requires a great deal of labor and time. Further, in the above-described calibration, the potentiometer is calibrated with a horizontal displacement in a direction opposite to the impact direction of the hammer, so that the calibration has poor reliability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a displacement calibration jig for an instrumented impact test apparatus which enables simple and highly accurate calibration of a potentiometer. Is to do.

[0006]

SUMMARY OF THE INVENTION A displacement calibration jig for an instrumented impact test apparatus according to the present invention (Claim 1) includes a holder detachably mounted on a test piece support of the impact test apparatus, and a holder. And a measuring device provided. This measuring instrument has a measuring element that comes into contact with the impact blade of the hammer, and measures the horizontal displacement of the hammer moved in the direction of impact from a freely suspended position.

According to the above displacement calibration jig (claim 1), the horizontal displacement of the hammer when the hammer is moved in the direction of impact from a freely suspended position with the holder mounted on the test piece support table is measured. The potentiometer is calibrated by measuring with a measuring instrument and comparing the measurement result with the output of the potentiometer. Examples of the measuring device include a micrometer head that determines the horizontal displacement of the hammer (claim 2) and a displacement meter that outputs the horizontal displacement of the hammer following the movement of the hammer in the impact direction (claim 2). Can be used.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown an instrumented Charpy impact tester having a machine frame 2. The machine frame 2 is erected on a base 4 on a floor via a base plate 6, and a hammer 8 is pivotally mounted on an upper portion thereof. The hammer 8 has an impact blade 10, and semiconductor strain gauges (not shown) are attached to both sides of the impact blade 10 near the edge thereof.

A hammer lifting motor 12 is arranged on the upper part of the machine frame 2 and rotates the hammer shaft of the hammer 8 via a power transmission path. The hammer 8 is shown by a solid line in the drawing. It can be pivoted and lifted to a prescribed lifting position. On the other hand, a test piece support 14 is provided below the machine frame 2.
Is composed of a pair of left and right mounting tables 16 and a pair of left and right receiving tables 18, and a hammer swing passage is secured between the mounting tables 16 and between the receiving tables 18. Therefore, the hammer 8 can drop from the lifting position shown in the figure, pass through the test piece support table 14, and then swing up to the opposite side as shown by the two-dot chain line in FIG. At this time, if the test piece is placed on the test piece support 14, the test piece is broken from the notch by the impact blade 10 of the hammer 8, and the energy required for the break is determined by the swing angle of the hammer 8. As a result of determining
The Charpy impact value of the test piece can be measured. At this time, the impact load of the test piece is measured based on the output from the strain gauge of the hammer 8.

In FIG. 1, reference numerals 20, 22, 2
4, 26, 28 are hook devices, scales, hand operation panels,
The brake handle and protective frame are shown. Referring to FIG. 2, a lifting mechanism of the hammer 8 is shown, and the lifting mechanism will be described below. The hammer 8 has a base end connected to the hammer shaft 30. The hammer shaft 30 extends horizontally and is supported by a sleeve shaft 34 via a pair of bearings 32. A tooth clutch 36 is interposed between one end of the sleeve shaft 34 and the hammer 8, and the tooth clutch 36 can interrupt connection between the sleeve shaft 34 and the hammer 8.

A worm wheel 40 is connected to the sleeve shaft 34 via a cam clutch 38, and a worm 42 meshes with the worm wheel 40.
The worm 40 is connected to the aforementioned power transmission path on the hammer lifting motor 12 side via a pair of bevel gears (not shown). Therefore, the above-mentioned tooth scratch 36
When the hammer lifting motor 12 is driven while the cam clutch 38 and the cam clutch 38 are connected together, rotational power is transmitted from the sleeve shaft 34 to the hammer 8 via the tooth clutch 36, whereby the hammer 8 is moved to a predetermined lifting position. Can be raised up.

The other end of the hammer shaft 30 is connected to the potentiometer 4
4 is connected to the input shaft of
Reference numeral 4 denotes the rotation angle of the hammer shaft 30, that is, the horizontal displacement of the hammer 8 when the hammer 8 passes through the test piece support 14 in the direction of impact. Therefore, according to such an instrumented Charpy impact tester, the strain gauge and the potentiometer 44
The relationship between the load and the time and the relationship between the load and the deflection can be obtained based on the output of (1).

Referring next to FIGS. 3 and 4, there is shown a displacement calibration jig 46 used for calibrating the potentiometer 44. The displacement calibration jig 46 will be described below. The displacement calibration jig 46 includes a holder 48,
The holder 48 is detachably attached to the test piece support table 14. More specifically, the holder 48 has a pair of left and right spacer plates 50, and the width of each spacer plate 50 is the same as the mounting table 16 of the test piece support 14.
Each spacer plate 50 is mounted on the mounting table 16 on the corresponding side of the test piece support table 14, and one end protrudes between the left and right mounting tables 16. However, a sufficient space is provided between the left and right spacer plates 50 to allow the hammer 8 to pass through the impact blade 10.

A plate-like mounting piece 52 is attached to the outer edge of each spacer plate 50 via a pair of screws 54. These mounting pieces 52 are in close contact with the outer surface of the mounting table 16 and are connected via connecting bolts 56. And can be fixed to the mounting table 16. Further, one end of each spacer plate 50 has an extended portion 58 integrally protruding from an inner edge thereof. These extending portions 58 extend between the pair of receiving stands 18 in parallel with each other,
The holder block 6 is connected to the tip thereof via a pair of screws 60.
2 are connected.

A micrometer head 64 is mounted on the holder block 62. The micrometer head 64 has a measuring element, ie, a spindle 66, which projects horizontally from the holder block 62 toward the space between the spacer plates 50. ing. Next, calibration of the potentiometer 44 using the displacement calibration jig 46 will be described.

First, the hammer 8 is set at a freely suspended position, and the holder 48 of the displacement calibration jig 46 is mounted on the test piece support 14 as shown in FIGS. In this state, the spindle 66 of the micrometer head 64 is brought into contact with the impact blade 10 of the hammer 8, the scale of the micrometer head 64 at this time is read, and the value is used as a reference value. Thereafter, the spindle 66 of the micrometer head 64 is retracted by a predetermined length in the impact direction of the hammer 8 from the projection position of the reference value. In this state, the hammer 8 is moved from the freely suspended position in the direction of impact, and the impact blade 10 is brought into contact with the tip of the spindle 66. The output of the potentiometer 44 and the retracted length of the spindle 66 at this time are determined. Based on
The output of the potentiometer 44 can be adjusted, that is, its calibration can be performed.

When the potentiometer 44 is calibrated based on the horizontal displacement of the hammer 8 in the direction of impact as described above, the output of the potentiometer 44 accurately indicates the displacement of the test piece during a break test of the test piece. Become. The horizontal displacement of the hammer 8 can be easily and arbitrarily set only by adjusting the spindle position of the micrometer head 64, so that the calibration accuracy of the potentiometer 44 can be further improved.

As described above, the potentiometer 4
Calibration of 4 is performed by moving the hammer 8 in the direction of impact. After that, the hammer 8 is moved in the opposite direction from the free hanging position, the horizontal displacement is measured, and the accuracy of the calibration is confirmed. You can also. The present invention is not limited to the above-described embodiment. For example, a digital or analog displacement meter 68 can be used instead of the micrometer head 64 as shown in FIG. .
The displacement gauge 68 has a rod-shaped probe 70 projecting from the holder block 62, and is configured to continuously output a signal corresponding to the amount of expansion and contraction of the probe 70.

According to the displacement calibration jig 46 having such a displacement meter 68, the displacement calibrating jig 46 is mounted on the test piece support 14 in the same manner, and the measuring element 70 of the displacement meter 68 abuts on the impact blade 10 of the hammer 8. In this state, the hammer 8 is moved from its free hanging position in the direction of impact, and based on the output of the displacement meter 68 and the output of the potentiometer 44 at this time,
It is also possible to automatically perform the calibration of the potentiometer 44.

In the displacement calibration jig 46, the specific configuration of the holder 48 can be variously changed.
Needless to say, the displacement calibration jig of the present invention can be applied not only to the instrumented Charpy impact tester but also to an instrumented impact test apparatus such as an instrumented Izod impact tester.

[0021]

As described above, according to the displacement calibration jig for the instrumented impact test apparatus of the present invention (claim 1), the holder detachably attached to the test piece support of the impact test apparatus. Since a measuring device for measuring the horizontal displacement of the hammer is attached to the device, the potentiometer can be easily calibrated based on the output from the measuring device and the output from the potentiometer for outputting the rotation angle of the hammer. Further, the calibration of the potentiometer can be performed based on an arbitrary horizontal displacement of the hammer in the impact direction, and the reliability of the calibration and the accuracy thereof can be improved.

When a micrometer head is used for the measuring device (claim 2), a displacement calibration jig can be easily obtained. When a displacement meter is used for the measuring device, the calibration of the potentiometer can be more easily performed. It can be carried out.

[Brief description of the drawings]

FIG. 1 is a schematic side view of an instrumented Charpy impact tester.

FIG. 2 is a cross-sectional view showing a structure around a hammer shaft of the impact tester of FIG.

FIG. 3 is a plan view of a displacement calibration jig mounted on a test piece support of the impact testing machine of FIG. 1;

FIG. 4 is a front view of the displacement calibration jig of FIG.

FIG. 5 is a plan view showing a displacement calibration jig of a modified example.

FIG. 6 is a diagram for explaining a conventional calibration procedure.

[Explanation of symbols]

 Reference Signs List 8 hammer 10 impact blade 30 hammer shaft 44 potentiometer 48 holder 56 connecting bolt 64 micrometer head (measuring device) 66 spindle (measuring device) 68 displacement meter (measuring device) 70 measuring device

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Koji Usami, Shirane, Shikata, Tokai-mura, Naka-gun, Ibaraki Pref. (72) Inventor Yuzo Ishii Kitajima-cho, Kitajima-cho, Toyohashi-shi, Aichi F-term (reference) 2G061 AA13 BA20 DA16 EA01 EA02 EA10 EB04

Claims (3)

[Claims] 1. An instrumented impact test device having a potentiometer for detecting a rotation angle of a hammer, a holder detachably mounted on a test piece support of the impact test device, and a holder provided on the holder. A measuring device having a measuring element for contacting an impact blade of the hammer, and measuring a horizontal displacement of the hammer moved in a direction of impact from a freely suspended position. Displacement calibration jig for instrumented impact test equipment. 2. The displacement calibration jig according to claim 1, wherein the measuring device is a micrometer head that determines a horizontal displacement of the hammer. 3. The instrumented impact test apparatus according to claim 1, wherein the measuring device is a displacement meter that follows the movement of the hammer in an impact direction and outputs a horizontal displacement of the hammer. Displacement calibration jig.