JPH068780B2 - Displacement measuring device for test piece of material testing machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a material testing machine in which a test piece is used as a material test, and particularly to a test piece displacement amount for measuring the displacement amount of the test piece. The present invention relates to a measuring device.

(B) Conventional technology For example, in order to test the material of a test piece under high temperature and high pressure, as shown in FIG. 5, the test piece (T.
P.) must be accommodated. Then, while applying a load to the test piece (TP), measure the displacement amount of the test piece (TP),
It is necessary to material test the test piece (TP) inside the high temperature and high pressure vessel (1). In the case of the tensile test, it is usually required to generate a displacement between the gauge marks of the test piece (TP) and measure the displacement amount between the gauge marks.

For this reason, conventionally, a pair of protrusions (2) were provided on the outer periphery of the test piece (TP) at an interval corresponding to the gauge length of the test piece (TP). Then, the pair of arms (3) is fitted into the protrusion (2) and fixed to the test piece (TP). Further, the detection rod (4) and the detection tube (5) were engaged with each arm (3). Therefore, when displacement occurs between the reference points of the test piece (TP), each arm (3) is displaced integrally with the test piece (TP). Detection rod
(4) and the detection tube (5) follow the test piece and the arm (2) and are relatively displaced. By this, the displacement amount of the test piece (TP) is taken out. Therefore, when the displacement amount of the detection rod (4) and the detection tube (5) is detected outside the high temperature and high pressure container (1), the displacement amount of the test piece (TP) can be measured.

However, in this test piece displacement amount measuring device, each arm (3) is integrally displaced with the test piece (TP) so that the detection rod (4) and the detection tube (5) follow each arm (3). Requires that each arm (3) be firmly fixed to the test piece (TP). For this reason, it was necessary to make the protrusion (2) of the test piece (TP) large. Increasing the protrusion (2) allows each arm (3)
Although it can be firmly fixed to the test piece (TP),
It is unavoidable that (2) affects the displacement of the test piece (TP). Therefore, there is a problem in that it is not possible to accurately measure the variable position between the gauge marks.

(C) Purpose Therefore, the present invention, in a material testing machine for material testing a test piece inside a sealed container such as a high temperature and high pressure container, it is not necessary to increase the protrusion of the test piece, and the displacement of the test piece can be accurately measured. It is intended to be measured.

(D) Structure According to the present invention, the test piece is housed inside the sealed container,
While applying a load to the test piece, the displacement amount of the test piece is measured, and in the material testing machine configured to test the material of the test piece inside the sealed container, a pair of arms inside the sealed container. One end is engaged with the test piece, an arm connecting member is provided between both ends of each arm, the respective arms are connected to each other by the connecting member, and further, there is an interval in a direction parallel to the load direction of the test piece. A first pair of fixed walls placed and opposed to each other is fixed to the hermetically sealed container, a first movable member is provided between the first pair of fixed walls, and expands and contracts in a direction parallel to a load direction of the test piece. The first pair of fixed walls and the first movable member are sealed by one bellows, and the second pair of fixed walls facing each other with a gap in a direction parallel to the load direction of the test piece is provided in the sealed container. Between the fixed wall of the second pair A second movable member is provided, and a space between the second movable member and the fixed wall of the second pair is sealed by a second bellows that expands and contracts in a direction parallel to the load direction of the test piece, and the first and second bellows are sealed. One of the inner side and the outer side is communicated with the inside of the hermetically sealed container, and the first and second can be performed by a rigid member protruding from the inside of the hermetically sealed container to one side of the first and second bellows. A rigid member that connects a member to the other end of each of the arms, provides first and second detectors outside the sealed container, and is arranged on the other side of the inside and the outside of the first and second bellows. The first and second detectors with the first
And a second movable member, and when the displacement of the test piece occurs, the arms are relatively swung with the connecting member as a fulcrum, and the swing amounts of the arms are detected by the detectors. There is provided a test piece displacement amount measuring device characterized by the above.

(E) Example Hereinafter, an example of the present invention will be described. FIG. 1 shows an embodiment of the present invention. The test piece (TP) is housed inside the high-temperature high-pressure container (6) and arranged vertically. High temperature and high pressure container
(6) is inserted inside the heating furnace (7). This tester is designed to perform a tensile test on a test piece (TP) inside a high temperature and high pressure container (6), and the test piece (TP) is chucked by a pair of upper and lower pull lots (not shown). Therefore, a pull load can apply a tensile load to the test piece (TP) to cause a displacement between the gauge points of the test piece (TP).

This tester has a pair of upper and lower arms (8H) and (8L), and the arms (8H) and (8L) are arranged horizontally and in parallel on the right side of the test piece (TP). The test piece (TP) consists of a pair of upper and lower protrusions (9
H) and (9L), and the protrusions (9H) and (9L) are provided on the outer periphery of the test piece (TP) at intervals corresponding to the gauge length of the test piece (TP). Then, inside the high-temperature high-pressure container (6), one end of each arm (8H), (8L) is fitted into the protrusions (9H), (9L),
It is engaged with the test piece (TP). Also, high temperature and high pressure container
An elongated arm accommodating sleeve (10) is formed as a part of (6), the sleeve (10) penetrates the wall surface of the heating furnace (7), and the arms (8H) and (8L) are inside the sleeve (10). It is housed in. Further, a leaf spring (11) is provided between both ends of the arms (8H) and (8L), and the arms (8H) and (8L) are connected to each other by the leaf spring (11). The upper arm (8H) is connected to the inner surface of the sleeve (10) by the coil spring (12).
The coil spring (12) is for supporting the weight of each arm (8H), (8L) and is provided at the same position as the leaf spring (11).

In addition, this tester has a pair of upper and lower differential transformers (13H), (13H).
L) and differential transformers (13H) and (13L) are high temperature and high pressure vessels.
It is provided outside (6). Furthermore, this tester has a pair of upper and lower bellows storage cases (14), and the cases (14) are arranged above and below the arm storage sleeve (10),
It is attached to the outside of the cold water jacket (15). The differential transformers (13H) and (13L) are composed of a coil (16) and a core (17), and the coil (16) is attached to the outer surface of the bellows housing case (14) and connected to the arithmetic unit (18). . Furthermore, a bellows (19) is housed inside each case (14),
(19) is arranged so as to expand and contract in the vertical direction. A through hole (20) is provided in the wall surface of the arm housing sleeve (10), and the high temperature and high pressure container (6) and the arm housing sleeve (10) are provided.
The inside of the bellows communicates with the inside of the bellows (19).

Further, in this embodiment, the detection rod (2) is used as a rigid member for connecting the differential transformers (13H), (13L) and the arms (8H), (8L).
1) and (21) are used, and the intermediate flange (23) is used as a movable member.
Is used. Furthermore, the wall surfaces of the cold water jacket (15) and the bellows housing case (14) are used as the fixed wall. The detection rod (21) penetrates the wall surface of the case (14) and is inserted outside the bellows (19), and the detection rod (22) penetrates the wall surface of the arm housing sleeve (10), and the bellows (19).
Is inserted inside. The detection rod (21) connects the cores (17) of the differential transformers (13H) and (13L) to the intermediate flange (23), and the detection rod (22) connects the intermediate flange (23) to each arm (8H). , (8L) is connected to the other end.
In addition, the bellows (19) allows the arm receiving sleeve (10).
Wall, intermediate flange (23) and bellows storage case (1
The walls of 4) are sealed. Therefore, the differential transformers (13H) and (13L) are connected to the arms by the detection rods (21) and (22) and the intermediate flange (23) which penetrate the wall surface of the arm housing sleeve (10), that is, the wall surface of the high temperature and high pressure container. (8H), (8
L), connected to the other end, in the vertical direction, that is, the test piece (TP)
The bellows (19) which expands and contracts in the displacement direction of (1) seals between the wall surface of the high temperature and high pressure container and its penetrating rigid member.

In the test piece displacement amount measuring device configured as described above, when displacement occurs between the reference points of the test piece (TP), each arm
(8H) and (8L) follow the protrusions (9H) and (9L) of the test piece (TP). Then, using the leaf spring (11) as a fulcrum, each arm (8H), (8H)
L) swings relatively. By this, the displacement amount of the test piece (TP) is taken out. Furthermore, the detection rods (21), (22) and the intermediate flange (23) follow each arm (8H), (8L),
Move up and down. The bellows (19) expands and contracts in the vertical direction to absorb the movement of the intermediate flange (23). Therefore,
Differential transformer (13H), (13L) core (17) detection rod (21)
And the coil (16) relative to the coil (16). Therefore, the swing amount of each arm (8H), (8L) is detected by each differential transformer (13H), (13L). The detection output is sent to the arithmetic unit (18), and the arithmetic unit (18) adds the detection outputs of the differential transformers (13H) and (13L). By this, the amount of displacement of the test piece (TP) is measured.

Therefore, unlike the above-mentioned conventional device, this device has an arm (8
It is not necessary to firmly fix H) and (8L) to the test piece (TP).
Each arm (8H), (8L) follows the projections (9H), (9L) of the test piece (TP) and can be relatively swung, and each arm (8H), (8L) can be lightly moved. All that is required is to fit one end of each of the protrusions (9H) and (9L). Therefore, the test piece (TP) protrusions (9H), (9L)
Does not have to be large.

The protrusions (9H) and (9L) can be made smaller, and the protrusions (9H) and (9L)
L) has almost no effect on the displacement of the test piece (TP). Therefore, the amount of displacement between the gauge marks can be accurately determined.

Further, in this device, the entire differential transformers (13H) and (13L), that is, the coil (16) and the core (17) can be arranged outside the high temperature and high pressure container (6). Furthermore, when the amount of displacement of the test piece (TP) is taken out, the arms (8H) and (8L) relatively swing about the leaf spring (11) as a fulcrum, and the bellows (19) expands and contracts in the vertical direction. Only, no friction problems arise. Therefore, the measurement accuracy of the differential transformers (13H) and (13L) is high.
Further, the internal pressure of the high temperature high pressure vessel (6) is guided to the inside of the bellows (19), and the detection rod (22) and the intermediate flange (23) receive the internal pressure of the high temperature high pressure vessel (6), but the bellows (19) If the radius is constant over its entire length, the upward and downward forces exerted on the intermediate flange (23) by the internal pressure are substantially the same and cancel each other out. Therefore, the internal pressure of the high-temperature high-pressure container (6) does not affect the measurement accuracy of the differential transformers (13H) and (13L), and the displacement amount of the test piece (TP) can be accurately measured. Moreover, the wall surface of the arm housing sleeve (10), the intermediate flange (23) and the wall surface of the bellows housing case (14) are sealed by the bellows (19), and there is no problem of leakage and durability. Therefore, there is no problem even if the high temperature high pressure gas or the high temperature high pressure liquid is enclosed in the container (6). It is also possible to enclose toxic gas or toxic liquid.

The arms (8H) and (8L) act as levers for expanding or contracting the displacement of the test piece (TP). The lever ratio can be arbitrarily selected depending on the position of the fulcrum of the arms (8H) and (8L), that is, the position of the leaf spring (11). Furthermore, most of the arms (8H) and (8L) are housed in the arm housing sleeve (10), not in the main body of the high temperature and high pressure container (6). Therefore, high temperature and pressure vessels (6)
The main body of does not need to be large, and can be made compact.

Various modifications of the present invention are possible. For example, as shown in FIG. 2, the inside of the sleeve (10) is communicated with the outside of the bellows (19) by the through hole (20) of the arm housing sleeve (10). Then, the detection rod (24) inserted inside the bellows (19) connects the cores (17) of the differential transformers (13H) and (13L) to the intermediate flange (23) and inserts them outside the bellows (19). The intermediate flange (2
3) may be connected to the tip of each arm (8H), (8L). Also in this case, the detection rods (24), (25) and the intermediate flange (23)
To the arm (8H), (8L), the differential transformer (13H),
The amount of swing of the arms (8H) and (8L) can be detected by (13L), and the same effect can be obtained.

Moreover, if similar functions such as arms (8H), (8L), differential transformers (13H) and (13L) are provided not only on the right side of the test piece (TP) but also on the left side, the test piece (TP) The displacement between the gauge marks can be measured on the left side. Therefore, it is possible to obtain the average value of the displacement amount between the reference points.

Also, instead of the leaf spring (11), such as a pin or pivot
Other connecting members may be used, and the arms (8H) and (8L) may be connected to each other by the connecting member. Furthermore, the arms (8H) and (8L) do not necessarily have to be arranged in parallel.
Depending on the case, the arms (8H) and (8L) may be crossed. In FIG. 3, a pair of arms (8H) and (8L) are crossed with each other and each arm (8H) and (8H) is connected by a pin or pivot (26).
L) is connected to each other. When a displacement occurs between the gauge points of the test piece (TP), each arm (8H), (8L) swings relative to the pin or pivot (26) as a fulcrum, and the differential transformer
The amount of swing of each arm (8H), (8L) is detected by (13H), (13L). Therefore, the amount of displacement of the test piece (TP) can be similarly measured. In addition, as shown in FIG. 4, a pair of differential transformers (13) are respectively connected to the arm housing sleeves (1).
It may be provided above 0). Further, instead of the differential transformer, other detectors such as an eddy current type detector, a capacitance type detector, an optical type detector, or a strain gauge type detector may be used.

Also, the projections (9H), (9L) are not always on the outer circumference of the test piece (TP).
Need not be provided. For example, one of the arms (8H) and (8L) and the test piece (TP) may be provided with a pin, another pin hole may be provided, and the pin may be inserted into the pin hole. The ends of the arms (8H) and (8L) may be pressed against the test piece (TP) by a coil spring. In short, arms (8H), (8H), (8H), (8L) swing so that each arm (8H), (8L) swings when displacement occurs between the gauge points of the test piece (TP)
It is sufficient to engage one end of L) with the test piece (TP). In addition, a test piece is provided by one end of each arm (8H), (8L).
When (TP) is sandwiched in the diametrical direction, the displacement amount can be measured in the diametrical direction. Further, the apparatus can be used for material tests other than the tensile test, for example, bending test or shear test, and the displacement of the test piece can be measured.

This device can also measure the displacement of a test piece inside a sealed container other than the high temperature and high pressure container, for example, a vacuum chamber.

(F) Effect As described above, according to the present invention, the sealed container (6)
In the inside, one end of the pair of arms (8H), (8L) engages with the test piece (TP), and arm connecting members (11) are provided between both ends of each arm (8H), (8L), The arms (8H) and (8L) are connected to each other by the connecting member (11). In addition, the test piece
The first pair of fixed walls facing each other at intervals in the direction parallel to the load direction of (TP) is fixed to the sealed container (6), and the first movable member (23) is provided between the first pair of fixed walls. The test piece (T.
P.) The first bellows (1
The space between the first pair of fixed walls and the first movable member (23) is sealed by 9). Similarly, the second pair of fixed walls facing each other at intervals in the direction parallel to the load direction of the test piece (TP) is the sealed container (6).
Fixed to the second movable member (23) between the second pair of fixed walls.
And a second pair of fixed walls and a second bellows (19) that expands and contracts in a direction parallel to the load direction of the test piece (TP).
The movable members (23) are sealed. Further, the first and second
One of the inner side and the outer side of the bellows (19) communicates with the inside of the sealed container (6), and a rigid member protruding from the inside of the sealed container (6) to one side of the first and second bellows (19). (22) causes the first and second movable members (23) to move to arms (8H), (8
L) is connected to the other end. Further, the first and second detectors (13H) and (13L) are provided outside the hermetically sealed container (6) and are arranged on the other side of the inside and outside of the first and second bellows (19). The rigid member (21) connects the first and second detectors (13H), (13L) to the first and second movable members (23). Therefore, when displacement of the test piece (TP) occurs, each arm (8H), (8L) swings relatively with the connecting member (11) as a fulcrum, and each detector (13H), (13L) By each arm
The swing amount of (8H), (8L) is detected. This gives the test piece
The amount of displacement of (TP) can be measured.

Therefore, according to the present invention, even with the test piece (TP) inside the sealed container (6), the displacement of the test piece (TP) can be measured by the external detectors (13H) and (13L). You can
Moreover, it is not necessary to firmly fix the arms (8H) and (8L) to the test piece (TP). Each arm (8
It suffices that the H) and (8L) oscillate relative to each other, and only one end of each arm (8H) and (8L) needs to be lightly engaged with the test piece (TP). Therefore, it is not necessary to provide the test piece (TP) with a large protrusion. Small protrusions (9H) and (9L) may be provided, and the protrusions (9H) and (9L) hardly affect the displacement of the test piece (TP). Therefore, the amount of displacement between the gauge marks can be accurately measured. The movable member (23) moves in the direction parallel to the load direction of the test piece (TP) between the first and second fixed walls, and the bellows (19) moves in the load direction of the test piece (TP). It only expands and contracts in the parallel direction and does not cause friction problems. There is no problem that the internal pressure of the sealed container (6) affects the measurement accuracy of the detectors (13H) and (13L). Therefore, the measurement accuracy of the detectors (13H) and (13L) can be enhanced, and the displacement amount of the test piece (TP) can be accurately measured. There are no problems of leakage and durability.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIGS. 2, 3, and 4 are explanatory views showing a modification of FIG. 1, and FIG. 5 is a conventional test piece displacement amount measurement. It is explanatory drawing which shows an apparatus. (TP) …… Test piece (6) …… High temperature and pressure vessel (8H), (8L) …… Arm (11) …… Leaf spring (13H), (13L) …… Differential transformer (19) …… Bellows (21), (22) …… Detection rod (23) …… Intermediate flange

Claims (1)

[Claims] 1. A test piece is housed in a sealed container, a load is applied to the test piece, a displacement amount of the test piece is measured, and a material test of the test piece is performed inside the sealed container. In the material testing machine described above, one end of a pair of arms is engaged with the test piece inside the sealed container, arm connecting members are provided between both ends of each arm, and the arms are connected to each other by the connecting member. Further, the first pair of fixed walls, which are opposed to each other with a gap in the direction parallel to the load direction of the test piece, are fixed to the sealed container, and the first movable member is provided between the first pair of fixed walls. The first bellows, which is provided and expands and contracts in a direction parallel to the load direction of the test piece, seals between the first pair of fixed walls and the first movable member, and an interval is provided in a direction parallel to the load direction of the test piece. The second pair of fixed walls placed facing each other The second movable member is fixed between the fixed container and the second pair of fixed walls, and the second movable member is expanded and contracted in the direction parallel to the load direction of the test piece by the second bellows. The two movable members are sealed and the first
One of the inner side and the outer side of the second bellows is communicated with the inside of the hermetically sealed container, and the rigid member protrudes from the inside of the hermetically sealed container to one side of the first and second bellows. First and second movable members are connected to the other ends of the arms, first and second detectors are provided outside the sealed container, and the other side of the inside and the outside of the first and second bellows is provided. The first and second detectors are connected to the first and second movable members by a rigid member disposed in the arm, and when the test piece is displaced, the arms are relatively rocked with the connecting member as a fulcrum. The test piece displacement amount measuring device, wherein the test piece displacement amount measuring device is configured to be moved, and the swing amount of each arm is detected by each of the detectors.