KR100938949B1 - A measuring instrument for compression stress relaxation - Google Patents

Abstract

The present invention relates to an apparatus for accurately measuring the compressive stress relaxation characteristics of an elastomeric material in a state in which a fluid such as oil (working oil) is filled, and displaying them externally.

An apparatus for measuring compressive stress relaxation characteristics according to the present invention includes a housing 20 that forms a space having a predetermined size therein, a test piece M placed inside the housing 20, and a pressing piece of the test piece M. A press block 30, a holder 40 forcing the press plate 30 to press the test piece M, and a space block for limiting the degree to which the press plate 30 presses the test piece M. (50), a load cell (60) for measuring the stress applied to the test piece (M), a transfer member (70) for transmitting the stress applied to the test piece (M) to the load cell (60), and the load cell It is provided between the 60 and the housing 20 is composed of a heat insulating member 80 and the like to prevent heat transfer. According to the present invention having such a configuration, there is an advantage that more accurate compressive stress relaxation characteristics can be measured.

Compression, Strain Relief, Test, Measurement, Elastomers

Description

A measuring instrument for compression stress relaxation

The present invention relates to an apparatus for measuring compressive stress relaxation characteristics, and more particularly, to an apparatus for accurately measuring the compressive stress relaxation characteristics of an elastomeric material in a state in which a fluid (working oil), such as oil, is filled, and displaying them externally. It is about.

The apparatus for measuring compressive stress relaxation characteristics according to the present invention may be used regardless of the material and the type of the test piece, but for the convenience of description, an example in which an elastomer called an elastomer is used as the test piece is used as an example. Listen and explain.

An elastomer is a high molecular compound that has a property of increasing many times when pulled by applying an external force and returning to its original length when the external force is removed. Representative examples of such elastomers include vulcanized rubber, which is called elastic rubber, and besides, elastic fiber (spandex), which is an elastomer without chemical bonding.

 Such elastomers are widely used throughout the industry for materials for packing and sealing. Elastomers are produced by chemical bonds. Over time, some of the bonds are broken, resulting in loss of chemical and physical properties.

This loss is then affected by the operating environment, such as temperature, pressure, and type of contact, over time.

In addition, the apparatus and method for evaluating elastomers used in packings and seals are based on ASTM (American Society for Testing Materials) or other standard tests.

However, the results of the conventional test are far from the harsh environment of the product to which the actual material is applied, so it is difficult to accurately predict the life of the material. That is, in general, because the measurement in the state exposed to the air or without the accurate device, it is difficult to measure continuously, the external force is acting, there is a problem that the long-term performance, life of the elastomer material is not measured accurately .

An object of the present invention is to solve the problems of the prior art as described above, and to provide a compressive stress relaxation characteristic measuring apparatus for evaluating the long-term performance of the elastomeric material used in the harsh environment of high temperature, high pressure.

Another object of the present invention is to provide an apparatus for measuring compressive stress relaxation characteristics that can be continuously tested.

Apparatus for measuring compressive stress relaxation characteristics according to the present invention for achieving the above object includes a housing for forming a space of a predetermined size therein; A test piece placed inside the housing; A press plate provided inside the housing and pressing the test piece; A holder provided inside the housing for forcing the press plate to press the test piece; A space block provided at an outer side of the test piece to limit a degree to which the press plate presses the test piece; A load cell spaced apart from the test piece to measure a stress applied to the test piece; A transfer member provided between the load cell and the test piece to transfer the stress applied to the test piece to the load cell; And a heat insulating member provided between the load cell and the housing to prevent heat transfer.

According to the compression stress relaxation characteristics measuring apparatus of the present invention as described above, the data processing device is connected to the load cell inside the compression device is exposed to the outside. Therefore, since the compressive stress measured by the load cell is displayed to the outside by the data processing apparatus in real time, there is an advantage that the ease of use is increased.

In the present invention, a high temperature fluid is filled inside the housing. In other words, the fluid is heated by a thermostat installed outside or inside. Therefore, since the test piece is located and measured in the fluid of such a harsh environment, there is an advantage that the reliability of the measurement data is improved.

In addition, in the present invention, while the heat insulating member is provided so that heat inside the housing is not transmitted to the load cell, the transmitting member is also made of a ceramic insulating material. Therefore, since the measured value is prevented from being changed by the external environment, there is an advantage that the measurement accuracy is improved.

In the present invention, the space block is installed to surround the test piece, while the space block is further provided with a fluid groove through which fluid can flow. Therefore, since a uniform pressure is applied to the entire test piece, there is an effect that a more accurate measurement of compressive stress relaxation characteristics can be measured.

Hereinafter, the configuration of the compressive stress relaxation characteristic measuring apparatus according to the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, the apparatus 10 for measuring compressive stress relaxation characteristics according to the present invention includes a plurality of components and has a predetermined size, and the measuring apparatus 10 includes a temperature controller 100 and a data processor 110. ) Etc. are connected and installed.

The temperature controller 100 is for supplying and recovering a high temperature fluid into the housing 20 to be described below. The fluid supply pipe is supplied and recovered between the temperature controller 100 and the measuring device 10. 102 and the fluid return pipe 104 are installed. Therefore, the hot fluid heated in the temperature controller 100 is circulated into the housing 20 through the fluid supply pipe 102 and the fluid recovery pipe 104.

In addition, the data processor 110 is to display the measured value measured from the measuring device 10 to the outside, and is connected to the load cell 60 to be described below. In the data processor 110, the measured values measured by the load cell 60 are displayed in numerical or graphed form in real time.

The measuring device 10 includes a housing 20 that forms a space having a predetermined size therein, a test piece M placed inside the housing 20, and a press plate 30 that presses the test piece M. FIG. ), A holder 40 forcing the press plate 30 to press the test piece M, a space block 50 for limiting the degree to which the press plate 30 presses the test piece M, and And a load cell 60 for specifying the stress applied to the test piece M, a transfer member 70 for transmitting the stress applied to the test piece M to the load cell 60, the load cell 60, Is provided between the housing 20 is made of a heat insulating member 80 and the like to prevent heat transfer.

As shown, the housing 20 has a cylindrical shape with an open top. Of course, such a housing 20 may be made of a rectangular pillar or other polygonal pillar in addition to the cylindrical shape.

The upper side of the housing 20 is shielded by a cover 22. The cover 22 has a disc shape corresponding to an upper end of the housing 20, and is fastened to the housing 20 by a plurality of cover bolts 24.

The bottom surface of the housing 20 is further provided with a seating recess 26 recessed downward as shown. The seating groove 26 is a portion on which the test piece M and the space block 50 are seated. That is, the seating groove 26 is formed to have a predetermined depth, to have a diameter corresponding to the outer diameter of the space block 50, so that the space block 50 is always mounted at a constant position.

Fluid is filled in the housing 20. In other words, the fluid serving as the hydraulic oil is filled. Accordingly, the inlet 28 through which the fluid is introduced and the recovery port 29 through which the fluid is discharged are formed on the side surface (left side in FIG. 1) of the housing 20.

The inlet 28 is formed at the upper half of the housing 20 and is connected to the fluid supply pipe 102. In addition, the recovery port 29 is formed in the lower half of the housing 20, and is connected to the fluid recovery tube 104.

The test piece M is placed on the inner bottom surface of the housing 20, that is, the center portion of the seating groove 26. The test piece M may be made of various kinds of materials causing a change in stress by compression. Here, the test piece M is made of an elastomer for convenience of explanation. That is, the test piece (M) is made of a columnar elastomer (elastomer) material having a predetermined height.

The press plate 30 is provided inside the housing 20 to press the test piece (M). That is, as shown, the press plate 30 is placed on the upper side of the test piece (M) to press the test piece (M) from the upper side.

The press plate 30 may also be formed in various shapes, but the case where the press plate 30 is formed as an example will be described.

The holder 40 is provided outside the press plate 30. The holder 40 is applied to the lower side by holding the outer end of the press plate 30, as shown in the shape of a disk having a predetermined diameter, or consists of a plurality of independent objects.

A holder 40 having a disc shape as shown is provided with a plurality of holder bolts 42. The holder bolt 42 is a portion that substantially applies a force to move the holder 40 downward. That is, the plurality of holder bolts 42 are screwed to the bottom surface of the housing 20 in a state where the holder bolts 42 are installed to penetrate the holder 40 as shown. Therefore, as the holder bolts 42 are fastened to the lower ends of the housings 20, the holders 40 gradually move downward and apply a force to the press plates 30.

The holder bolts 42 are preferably provided with a plurality. That is, three are installed to maintain an angle of 120 degrees to each other, or four are installed to maintain an angle of 90 degrees to each other as shown in FIG.

A fixing groove 44 corresponding to one end of the press plate 30 is formed in the holder 40. That is, as shown, a fixing groove 44 is formed on one side (left or right in FIG. 1) of the holder 40 is accommodated one end of the press plate 30. The fixing groove 44 is a portion in which the edge of the press plate 30 is accommodated. Therefore, the fixing groove 44 is formed to have a circular cross-sectional surface corresponding to the rim of the plate-shaped press plate 30. (Fig. 1 is a front section, so is shown in the shape of '┏' '┓')

The space block 50 is spaced apart from the outside of the test piece (M). That is, as shown, the circular test piece (M) is formed in an annular ring (ring) shape so as to be accommodated inside, is formed to surround the side of the test piece (M) as a whole.

The space block 50 is made of a rigid body having no elasticity, and serves to limit the test piece M from being pressed and deformed by the press plate 30. That is, the press plate 30 forcibly presses the test piece M upward from the lower side by the holder 40 so that the bottom surface of the press plate 30 contacts the upper surface of the space block 50. If so, the lowering of the press plate 30 is stopped.

The transfer member 70 is provided between the load cell 60 and the test piece M to transfer the stress applied to the test piece M to the load cell 60.

Looking more specifically, the transmission member 70 is installed to penetrate the bottom surface of the housing 20 up and down. That is, the transmission member 70 is installed to penetrate up and down the center of the bottom surface of the housing 20, the top is installed to form the same plane as the bottom surface of the seating groove 26 of the housing 20.

The transfer member 70 may be formed to have a variety of shapes, but is preferably formed in a cylindrical shape, made of a ceramic heat insulating material to prevent heat transfer. Therefore, the heat of the fluid filled in the housing 20 is prevented from being transferred to the load cell 60 through the transfer member 70.

A sealing member 90 is further provided between the transfer member 70 and the housing 20 to prevent the fluid inside the housing 20 from leaking. That is, as shown, a member groove 72 recessed inwardly is formed on the outer circumferential surface of the transmission member 70, the member groove 72 is further provided with a sealing member (90).

The sealing member 90 is made of a material having elasticity, such as rubber, the fluid filled in the housing 20 leaks to the lower side of the housing 20 through a gap between the transfer member 70 and the housing 20. Block to prevent The sealing member 90 is composed of an annular O-ring.

The heat insulating member 80 is provided between the housing 20 and the load cell 60 to block heat transfer. That is, the heat insulating member 80 is formed in a disc shape corresponding to the cross section of the housing 20, and is installed below the housing 20.

The heat insulating member 80 is made of a material that is not heat transfer. Preferably, the heat insulating member 80 is preferably made of a ceramic heat insulating material. And, as shown, the transmission member 70 penetrates up and down in the central portion of the heat insulating member (80).

Below the heat insulating member 80, a disk-shaped support plate 82 corresponding to the heat insulating member 80 is further provided. The support plate 82 is for supporting components such as the housing 20 and the heat insulating member 80, and the support plate 82 is installed to penetrate the support plate 82 up and down.

The base plate 84 is spaced apart below the support plate 82. That is, the support plate 82 is installed at a predetermined interval on the upper side of the base plate 84 forming the bottom. Therefore, a base support 86 is provided between the base plate 84 and the support plate 82.

The base support 86 is made of a cylindrical shape. Therefore, a predetermined space is formed inside the base support 86 as shown, and the load cell 60 is installed in this space.

The load cell 60 is connected to the external data processor 110 to provide the measured compressive stress to the outside, and the upper end is installed to contact the lower end of the transfer member 70 to the test piece M. The compressive stress applied is measured. That is, the load cell 60 and the test piece (M) are installed to be spaced apart from each other, the transfer member 70 is installed between the load cell 60 and the test piece (M).

A plurality of bolts are fastened to the base plate 84 to fix each of the upper components.

Specifically, the long fastening bolt 92 to fix all the parts of the base plate 84, that is, the base support 86 and the support plate 82 and the heat insulating member 80 and the housing 20 integrally ) Is fastened about three, and then, a plurality of cell fixing bolts 94 for fixing the load cell 60 to the base plate 84 is provided.

2 and 3 illustrate the configuration of the space block 50 in more detail. That is, a plan view of the space block 50 is shown in FIG. 2, and a front sectional view of the space block 50 is shown in FIG. 3.

As shown in these figures, the space block 50 is formed in a ring shape surrounding the outside of the test piece M, and a fluid groove 52 through which fluid flows is formed.

In more detail, as shown, the space block 50 has an annular ring shape having a predetermined thickness, and the fluid grooves 52 are recessed to be rounded downwards in front, rear, left and right. Therefore, the fluid inside the housing 20 flows smoothly into the space block 50 through the fluid groove 52.

Hereinafter, a process of measuring compressive stress using the apparatus for measuring compressive stress relaxation characteristics as described above will be described.

First, as shown in FIG. 4, the test piece M and the space block 50 are placed on the seating groove 26 of the housing 20 in a state where the cover 22 is peeled off, and then the press plate 30 is placed on the press plate 30. Place it on top of the specimen (M).

In this case, the press plate 30 is in contact with the upper surface of the test piece (M) and at the same time spaced apart from the upper surface of the space block 50, thereby forming a gap.

Next, the holder 40 is placed on the press plate 30 from above and fastened to the housing 20. That is, the holder bolts 42 are fastened to the bottom surface of the housing 20. At this time, the press plate 30 is received and fixed into the fixing groove 44 of the holder 40.

When the holder bolt 42 is continuously tightened in the above state, the press plate 30 is moved downward by the pressing force of the holder 40 to press the test piece M, and the test piece ( M) is compressed by elasticity, and the height is reduced.

When the holder bolt 42 is continuously rotated as described above, the press plate 30 is lowered, and eventually the lower surface of the press plate 30 comes into contact with the upper surface of the space block 50.

When the press plate 30 is in contact with the space block 50, the press plate 30 is supported by the space block 50, so that the press plate 30 is no longer lowered.

In this state, the cover 22 is closed, and a fluid (working oil) is filled in the housing 20 to make a measurement. Therefore, the fluid in the housing 20 also flows into the space block 50 through the fluid groove 52 of the space block 50, and the load cell 60 is the test piece with the change of time The compressive stress change of (M) is transmitted to the data processor 110.

Thus, the user can view the compressive stress results of the test piece M tabulated in real time through the data processor 110.

5 is a cross-sectional view illustrating a state in which the press plate 30 moves downward by the holder 40 and finally contacts the upper surface of the space block 50.

The scope of the present invention is not limited to the above-exemplified embodiments, and many other modifications based on the present invention will be possible to those skilled in the art within the above technical scope.

For example, in the above embodiment, the thermostat 100 is installed outside the housing 20 of the measuring device 10 to supply a high temperature fluid into the housing 20 as an example. It is also possible to configure such a heater 100 is installed in the housing 20.

That is, the heater (heating fluid) inside the housing 20 is directly heated by installing a heater or the like in the housing 20 inside the housing 20 and supplying power from the outside to heat the heater. It will be possible to make it possible, it is also possible to further configure a separate circulation device in the housing 20 such that the fluid (working fluid) to circulate itself in the housing.

1 is a cross-sectional view showing the configuration and use of a preferred embodiment of the apparatus for measuring compressive stress relaxation characteristics according to the present invention.

Figure 2 is a plan view showing the configuration of a space block constituting an embodiment of the present invention.

3 is a front sectional view of the space block shown in FIG. 2;

Figure 4 is an exploded view showing an installation state of the embodiment of the present invention.

5 is a cross-sectional view showing a state of use of the embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

10. Measuring device 20. Housing

30, pressplate 40. Holder

50. Space Block 60. Load Cell

70. Transmission member 80. Insulation member

90. Sealing member M. Test piece

Claims (12)

A housing 20 defining a space having a predetermined size therein; A test piece (M) placed inside the housing (20); A press plate (30) provided inside the housing (20) for pressing the test piece (M); A holder (40) provided inside the housing (20) for forcing the press plate (30) to press the test piece (M); A space block (50) spaced apart from the test piece (M) and configured to limit the degree to which the press plate (30) presses the test piece (M); A load cell 60 spaced apart from the test piece M to measure a stress applied to the test piece M; A transfer member (70) provided between the load cell (60) and the test piece (M) to transfer the stress applied to the test piece (M) to the load cell (60); Compression stress relaxation characteristics measuring apparatus, characterized in that it comprises a; is provided between the load cell (60) and the housing (20), to prevent heat transfer. The apparatus of claim 1, wherein a fluid is circulated in the housing and the fluid is heated by a temperature controller. The method of claim 1, wherein the holder 40, Compression stress relaxation characteristics measuring device, characterized in that made of a plurality, the fixing groove 44 corresponding to one end of the press plate 30 is formed. The method of claim 1, wherein the space block 50, Compression stress relaxation characteristic measuring device characterized in that the test piece (M) is formed in a ring shape surrounding the outside, the fluid groove 52 is formed to flow across the fluid. The method of claim 1, wherein the bottom surface of the housing 20, Compression stress relaxation characteristics measuring apparatus characterized in that the seating groove (26) is formed to be seated on the test piece (M) and the space block (50). The method according to any one of claims 1 to 5, wherein between the transfer member 70 and the housing 20, Compression stress relaxation characteristics measuring apparatus further comprises a sealing member (90) for preventing the leakage of the fluid in the housing (20). The method of claim 6, wherein the load cell 60, Connected to an external data processor (110), the compressive stress relaxation characteristics measuring apparatus, characterized in that for providing the measured compressive stress to the outside. A housing 20 forming a space having a predetermined size therein; A test piece (M) placed inside the housing (20); A press plate (30) provided inside the housing (20) for pressing the test piece (M); A holder (40) provided inside the housing (20) for forcing the press plate (30) to press the test piece (M); A space block (50) spaced apart from the test piece (M) and configured to limit the degree to which the press plate (30) presses the test piece (M); A load cell 60 spaced apart from the test piece M to measure a stress applied to the test piece M; A transfer member (70) provided between the load cell (60) and the test piece (M) to transfer the stress applied to the test piece (M) to the load cell (60); It is provided between the load cell (60) and the housing (20), and has a configuration including a heat insulating member (80) to prevent heat transfer; The transfer member 70 and the heat insulating member 80 is a compressive stress relaxation characteristic measuring device, characterized in that made of a ceramic (ceramics) insulating material. The apparatus for measuring compressive stress relaxation characteristics according to claim 8, wherein the holder is composed of a plurality of holders. The method of claim 8 or 9, wherein the space block 50, Apparatus for measuring compressive stress relaxation characteristics, characterized in that further fluid grooves 52 are formed to allow fluid to flow. The method of claim 10, wherein between the transmission member 70 and the housing 20, Compression stress relaxation characteristics measuring apparatus further comprises a sealing member (90) for preventing the leakage of the fluid in the housing (20). The method of claim 11, wherein the sealing member 90, Compression stress relaxation measuring device characterized in that the O-ring (O-ring).

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