JP2735657B2 - Tester or test machine for test piece or test object and its test method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a structural component connected to a relatively moving tester, particularly to a structural component connected to a tester frame and a structural component connected to a movable test piece clamping device. The present invention relates to a test device or a test method for a test piece or a test object, which has at least one connection device and is provided with a fluid for the connection.

[Conventional technology]

A testing machine having such a connecting device is employed, for example, as a high-speed rupture testing machine. The high-speed rupture test is performed under the condition that a load is applied to the test piece as shockingly as possible.
In the case of a known high-speed rupture tester, a load force is generated in a state in which a connecting device as a run-up device is employed. In this case, the extension of the movable part, which accelerates as it follows the approach distance, strikes via a hydraulic stop against a projection fixedly arranged on the frame, which causes the required impact load of the test specimen. A testing machine equipped with such a device is, for example,
Zwick GmbH & Co. company report "Universal type testing machine system 1800 for high-speed testing" Nr.7.22.1.04.PI 100 1.
Known at 287.102. However, in the event of an impact, there is always an undesired uncontrollable bouncing action for the intended load of the specimen. Furthermore, because the reaction time of the valve is fast in seconds, the test force can only be adjusted or tracked very inaccurately. Furthermore, the final acceleration can only be determined very roughly by the approach distance.

Liquids whose flow properties change under the action of an electric field are known and are called electrorheological liquids or electrorheological or rheological electric liquids. In most cases, the dispersion medium is a dispersion medium of a hydrophilic solid finely dispersed in an electrically nonconductive hydrophobic liquid. Under the action of a modifiable sufficiently strong electric field, the viscosity of an electrorheological liquid can change from a liquid state to a solid state via a plastic state at a rate of microseconds. This process is reversible. DC or AC electric fields can be used.

It is also known to use electro-rheological liquids for controllable viscous clutches (see DE-A 31 28 959). In this clutch, the electrorheological liquid exists between the rotating clutch elements as a force transmitting mechanism, and a potential difference is generated between the clutch elements in order to change the shear viscosity of the liquid. The clutch is electrically controlled between a substantially completely disengaged state and a completely entrained state.

[Problems to be solved by the invention]

It is an object of the present invention to enable a test machine of the type described at the outset to be controlled reliably and accurately in a simple structure in a short time, for example in the adjustment of forces, travel distances, speeds, accelerations and shock or vibration loads. In order to allow various operation modes, it is desirable to form the apparatus.

[Means for solving the problem]

According to the invention, this object is achieved in a test machine of the type mentioned at the outset in that the fluid is an electrorheological liquid and the opposed electrodes delimiting at least one flow path are arranged in at least one structural part and / or in each case. Attached to the structural parts,
This is achieved by having a connection terminal for applying a control voltage.

〔The invention's effect〕

According to the present invention, the accuracy of the test results and the reliability of the test report for the test object or test piece associated therewith,
This is enhanced by the provision of hydraulic and electrical means that can accurately maintain and regenerate high dynamic load handicap (Vorgabe). For the first time in the field of test technology, it is possible to obtain load force handicap and acceleration handicap accurately in a short time (speed in microseconds). The coupling device can be easily adapted to various test programs or test objects based on electrical control or regulation.

The embodiment according to claim 2 is advantageous in terms of manufacturing and assembly.

Two specimen clamping devices with pistons are provided, one piston being movable in a housing surrounding a given liquid volume and the other piston being hydraulically movable in a housing having a connection tube. In one embodiment, one piston is moved to any position compatible with the test configuration and the other piston hydraulically loads the specimen.

Advantageously, the piston in the housing surrounding a given liquid volume is the piston of the starting device and is spaced from the housing wall at the end position of the other piston. Through a fluid pressure piston, a system composed of a fluid pressure piston, a test piece fastening device, a test piece, a test piece fastening device, and a second piston is accelerated, and the viscosity of the electrorheological liquid causes the second piston to be accelerated. The specimen is loaded by force, either shock-restrained in the housing supported by the frame and by more permanent pressure loading of the hydraulic piston or by the inertial mass of the piston and the structural components connected to it. Is done.

If the test specimen clamping devices are rigidly connected to each other and one of the pistons or a structural component connected to the piston, for example a hydraulic piston, is provided with a test specimen storage device, the test of the test specimen or the test object is performed with an extremely high deceleration force. I can do it. For this purpose, the piston of the start-up device is controlled and shock-restrained, while at the same time the fluid chambers on both sides of the hydraulically movable piston are hydraulically short-circuited, so that no hydraulic pressure is applied to the piston, and therefore There is no acceleration limitation.

Advantageously, the effective area of the hydraulic piston is very small due to the effective area of the piston of the start-up device. Due to the different piston areas, only a small valve is required to speed up the hydraulic piston.

Advantageous embodiments of the invention are described in the further embodiments.

In order to achieve the object of the present invention, an electrorheological liquid is used as the fluid, and the electrorheology is controlled or adjusted by applying a control voltage, and the control thereof is performed in the method according to the preamble of claim 19. Alternatively, the adjustment is characterized as a function of a stroke distance and / or of a force applied to the test piece or test piece and / or of a motion state of at least one structural component connected to the test piece or test piece. In addition, it is proposed to be performed according to at least one state quantity. It is particularly simple for the control to involve the travel distance of the piston of the coupling device formed as a start-up device.

Control or adjustment methods that can be easily adapted to various test purposes include the forces applied to the test specimen or test object to control, the acceleration of the test specimen clamping device attached to the coupling device (running device), and the fluid. Care is taken that the speed of the working piston is involved.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

The test machine shown in FIG.
And a frame 1 for supporting the second test piece clamping device 3 and the test piece 21 is clamped between the two test piece clamping devices 2 and 3. The frame 1 is elastically supported on a foundation 4. The frame 1 is composed of, for example, a horizontally arranged tester table (lower part in the drawing), two vertically arranged guide columns, and a horizontal cross beam (upper part in the drawing). Locked.

The upper clamping device 2 in the drawing is provided with a force measuring device 5, for example, German Patent Application 37
It is formed as proposed in Japanese Patent Publication No. 20303.7. The test piece clamping device 2 further has an acceleration detector 6. The test piece clamping device 2 is connected to a piston 8 via a piston rod 7. This piston 8 can move within a housing 9 attached to the upper frame part. The housing 9 is filled with an electrorheological liquid. Two fluid chambers 10, 10 'are defined by the piston 8, and these fluid chambers 10, 10' communicate with each other via a flow path. The flow path is formed by, for example, a number of slits 11. These slits 11 are provided on the circumference of the piston 8 and extend substantially parallel to the axis. The slit 11 forms a capacitor, i.e. the opposing slit walls are insulated from each other and form electrodes 11a, 11b, each of which has a connection to a power supply.

The lower second test piece clamping device 3 in the drawing is connected to a piston 13 via a piston rod 12.
The histone 13 can be airtightly and hydraulically moved within a housing 14 mounted in the lower area of the frame 1. Since the fluid chambers 15, 15 'on both sides of the piston 13 can be connected to a fluid source or return path in the form of a pump, the piston 13 can be moved in the direction of the first specimen clamping device 2 when the pressure is applied, or It can move in the opposite direction or provide a corresponding force. An electrorheological liquid is used as a working fluid. The fluid chamber 15 'is connected to the outflow passage 16 leading to the return passage 28. Electrodes 17a, 17b are arranged in the outflow channel 16,
Each of these electrodes 17a and 17b has a connection terminal for a power supply. The piston 13 has another piston rod 18 projecting downward from the housing 14 in the drawing. The piston rod 18 has, for example, a lower end connected to the test piece storage device 19. The test piece storage device 19 is attached to a structural component connected to the piston 13 at an arbitrary position. A measuring device 24 for detecting the speed of the piston or for detecting the speed of the test piece 20 stored in the test piece storage device 19 is provided between the housing 14 and the piston rod 18 or the test piece storage device 19. I have.

When the specimen 20 is accommodated in the specimen accommodating device 19 as shown by the broken line, the specimen clamping devices 2 and 3 are firmly connected to each other in a manner not shown without clamping the specimen. Or not connected to each other. When the mass of the test object is very small,
A method is adopted in which 2, 3 is not positively connected. This is because a high dynamic characteristic of the system can be obtained with a small vibrating mass.

The piston 8 / housing 9 device forms a start-up device 25, which is designed such that the piston 8 can be locked in the housing 9 in a preferential position.
For this purpose, a voltage is applied to the electrodes 11a and 11b of the slit 11. This voltage increases the viscosity of the electrorheological liquid so that the liquid can be considered solid within the slit area.

The output terminals of the force measuring device 5, the acceleration detector 6, and the measuring device 24 are led to the adjusting device 30 via wirings K, B, and V.
The output side of the adjusting device 30 is connected to a high-voltage generator 31, and through the high-voltage generator 31, the electrodes 11a, 11b, 17a, 17b, 26a, 26b
(See FIG. 3), a voltage is supplied according to the control. A target value is introduced on the input side.

In the process of the high-speed fracture test, the test piece 21 is fastened and fixed to the test piece fastening devices 2 and 3. The pistons 8 and 13 are preferably in terminal positions at the upper ends of the housings 9, 14, respectively. The piston 13 passes through a servo valve 27,
It is moved so as to descend at high speed, that is, move in the direction of arrow 41. The same pressure then occurs in the cylinder chambers 15,15. The electrorheological liquid in the housing 9 has a low viscosity, while the electrodes 17a and 17b in the housing 14 are applied with a high voltage, and the high viscosity of the liquid in the electrode area causes the fluid 16 to flow out of the fluid chamber 15 and the outlet 16 and Therefore the return path
Fluid outflow to 28 is reliably prevented. The speed of the piston 13 is measured by the measuring device 24.

When the desired speed (breaking speed) is reached, a voltage of sufficient height is applied to the electrodes 11a, 11a, the liquid hardens in the area of the slit 11, and the piston 8 is impulsively linked to the frame 1 according to the housing 9. Locked. The load force is applied to the test piece 21 in an impact at a speed of a microsecond unit.

Since the breaking speed to be kept constant decreases according to the breaking stroke distance of the test piece 21, the fluid is controlled and flows out of the fluid chamber 15 'to the return path 28 through the outflow path 16 so that
An auxiliary differential pressure is applied to the piston 13 in the direction of arrow 41. This keeps the breaking rate constant.

Since the viscosity changes electrically in microseconds, precise control of the force, speed and acceleration when loading the test specimen can be achieved by continuous voltage changes. For this purpose, the signals of the measuring devices 5, 6, 24 for forces, velocities and accelerations are guided to the control device 30 and are evaluated individually or in any combination depending on the handicap and possibly in relation to the travel distance. . The required voltage is guided to the electrodes 11a, 11b, 17a, 17b, 26a, 26b via the wiring via the high voltage generator 31.

When testing the acceleration of the test piece 20 or the DUT with a testing machine, the test piece 20
Fastened to 19. The specimen clamping devices 2, 3 are connected directly to one another or via force transmission rods of sufficiently large dimensions. The piston 13 is set at a high speed with a relatively small acceleration.

The fluid chambers 15 and 15 'are short-circuited, and at the same time, the flow path formed by the slit 11 is restrained by the application of voltage to the electrodes 11a and 11b.
20 is greatly reduced. Voltage is applied to the electrodes 17a and 17b.

The testing machine shown is also used for high-speed compression tests,
In this case, the load piston 13 is moved upward, that is, in the direction indicated by the arrow 40.

FIG. 2 shows a different embodiment of the approach device 25. Its operation is the same as that of the run-in device in FIG. 1, and a description thereof will be omitted. The piston 8 in the housing 9 is formed as a solid body in this embodiment. The electrodes 11a and 11b are arranged outside the housing 9 and in a flow path 26 connecting the fluid chambers 10 and 10 'to each other.

The electrodes 11a and 11b are insulated from each other and have connection terminals for voltage supply.

In the case of the embodiment in FIG. 3, the piston 8 is formed as a solid body in the piston 8 and housing 9 device.
An annular gap 26 is provided between the housing 9 and
An electrode 26a is arranged on the housing 9, and an electrode 26b is arranged on the outer periphery of the piston 8. In the case of this embodiment, the piston 8 is constrained by applying a voltage to the electrodes 26a and 26b at an arbitrary position. A slip ring 34 is provided on the piston rod 7 of the piston 8 for applying a voltage,
A synthetic resin ring 35 for insulation is fitted into the hole of the housing.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a testing machine according to the present invention, and FIGS. 2 and 3 are schematic configuration diagrams of different embodiments of the approaching device. DESCRIPTION OF SYMBOLS 1 ... Frame 2 ... Specimen clamping apparatus 3 ... Specimen clamping apparatus 5 ... Force measuring apparatus 6 ... Acceleration measuring apparatus 8 ... Piston 9 ... Housing 10 ... Fluid chamber 10 ... Fluid chamber 11 ... … Slit 11a …… Electrode 11b …… Electrode 13 …… Piston 14 …… Housing 15 …… Fluid chamber 15 …… Fluid chamber 17a …… Electrode 17b …… Electrode 24 …… Velocity measuring device 25 …… Running device 26a …… Electrode 26b …… Electrode

Claims (21)

(57) [Claims] 1. The apparatus according to claim 1, further comprising at least one connecting device for connecting the relatively moving tester structural parts, in particular the structural parts connected to the tester frame and the structural parts connected to the movable test piece clamping device. The test piece or the test device for which the fluid is prepared for the test, the fluid is an electrorheological liquid, and the electrodes (11a, 11b; 17a, 17b; ; 26a,
26b) At least one of the structural parts and / or each of the structural parts has a connection terminal for applying a control voltage, and a test device for a test piece or a test object. 2. One of the structural parts is formed as a housing (9, 14) and the other structural part has a piston (8, 13) movable within the housing (9, 14). 13), the two fluid chambers (10, 10 '; 15, 1) in which the housing chamber communicates via at least one flow path.
The testing machine according to claim 1, wherein the testing machine is divided into 5 '). 3. The tester according to claim 2, wherein the housing (9) is connected to the frame (1) and surrounds a predetermined liquid volume. 4. A housing (14) is connected to the frame (1), and at least one fluid chamber (15, 15 ') is provided in a fluid supply or return pipe for moving the piston (13) with fluid pressure. 3. The tester according to claim 2, wherein the tester is connected. 5. A test piece clamping device (2,3) having pistons (8,13), one of which is moved in a housing (9) surrounding a predetermined liquid volume. 5. The testing machine according to claim 2, wherein the other piston (13) can be moved hydraulically in a housing (14) provided with a connecting tube. 6. A piston (8) in a housing (9) surrounding a predetermined liquid volume is the piston of the starting device (25) and is spaced from the housing wall at the end position of the other piston (13). The testing machine according to claim 5, comprising: 7. The test piece, wherein the test piece (20) or the test object is located on one of the pistons (8, 13) when the test piece clamping devices (2, 3) are firmly connected or not connected to each other. 7. The test piece receiving device (19), which is mounted on the receiving device (19) or on a structural component connected to the piston, preferably on a hydraulic piston (13). The testing machine according to any one of the above. 8. The device according to claim 1, wherein the flow path has an annular gap between the piston and the housing wall.
8. The testing machine according to any one of items 7 to 7. 9. A method according to claim 1, wherein the flow path is formed by a slit (11) provided in the circumference of the piston (8) and preferably extending in the longitudinal direction. The testing machine described. 10. The testing machine according to claim 1, wherein the flow path is arranged outside the housing. 11. The flow channel (32) is provided with a plate-like electrode (11a, 11
11. The testing machine according to claim 10, wherein the testing machine is bounded by b). 12. The testing machine according to claim 1, wherein the viscosity can be adjusted or controlled according to force, acceleration, speed, or travel distance, or a combination thereof. 13. In order to adjust or control the piston (8) of the starting device (25) as a function of the travel distance, opposed electrodes (26a, 26b) are arranged offset from one another in the direction of movement. 13. The testing machine according to claim 12, wherein: 14. The testing machine according to claim 5, wherein the viscosity control for both piston housing devices is performed in an inverse relationship. 15. The test piece clamping device (2) connected to the piston (8) of the starting device (25) is provided with a force measuring device (5) and / or a measuring device for the state of motion. The test machine according to any one of claims 1 to 14. 16. A piston housing device having a hydraulic piston (13) is provided with a device (24) for measuring the movement of the piston (13), in particular a device for measuring the speed of the piston (13). The test machine according to any one of claims 1 to 15, wherein: 17. A measuring device (6) for measuring the motion of a test piece clamping device (2) attached to a running-in device (25) and / or a measuring of the motion of a hydraulic piston (13). A device (24) is connected to the control device (30), which applies a voltage to the electrodes (11a, 11b; 17a, 17b; 26a, 26b) of one or both piston housing devices. 17. The test machine according to claim 16, wherein the device is connected downstream. 18. The tester according to claim 1, wherein the effective area of the piston is much smaller than the effective area of the piston. 19. The apparatus according to claim 19, further comprising at least one coupling device for connecting the relatively moving tester structural parts, in particular, the structural parts connected to the tester frame and the structural parts connected to the movable test piece clamping device. In a method for controlling or adjusting the load applied to a test piece or a test object in a test machine in which a fluid is prepared for use, an electrorheological liquid is used as the fluid, and the electrorheology is controlled or adjusted by applying a control voltage. The control or adjustment thereof depends on the travel distance and / or on the force applied to the test piece or the test piece and / or the movement of at least one structural part connected to the test piece or the test piece. A test method for a test piece or a test object, which is performed according to at least one state quantity characterizing a state. 20. In order to control, a connecting device (a starting device 2)
20. The method according to claim 19, wherein the travel distance of the piston (8) of 5) is involved. 21. A control device for controlling a force applied to a test piece or a test object, an acceleration of a test piece tightening device (2) attached to a coupling device (propulsion device 25) and a hydraulic piston (13). Claims wherein speed is involved
19. The method according to 19 or 20.