FI78559C - ANORDNING FOER PROVBELASTNING OCH KVALITETSKONTROLL. - Google Patents

Description

78559

Koestus- ja Qualityunvalvontani te - Anordning för provbelas tuning och kvalitetskontroll

The invention relates to a testing and quality control device, in particular for performing bending, tensile and compression tests, the device comprising a fixed body part, a movable body part or a bushing, means for supporting the body to be tested with respect to the body part and a fixed body part and a movable body part. a part or a hydraulically actuated force element arranged between the buffer to apply a force to the object to be tested.

Several test and quality control devices of this type are known in the art. However, most of these devices are characterized by a very complex structure and therefore a very high price. On the other hand, there are also test devices with a fairly simple structure and relatively inexpensive, in which, however, the biggest problem is usually the dependence of the measurement results on the user of the device. In these devices, the load velocity is highly dependent on external factors and thus causes high scatter and inaccuracies in the measurement results, which in turn means that the structures under measurement have to be dimensioned unnecessarily strong due to the inaccuracy of the test method.

The object of the invention is to provide a testing and quality control device which is inexpensive, but nevertheless very accurate, and the measurement results obtained by means of which device are independent of the user of the device.

According to the invention, this object is solved in such a way that the liquid acting as the medium of the power element is connected via a shut-off valve to the liquid space of the pressure tank and the air space of the tank

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2 78559 in turn is connected to a source of compressed air, and that at least one booster is connected to the liquid space between the power element and said shut-off valve, the positive side of which is connected to the source of compressed air via a flow regulator, either directly or using liquid as a pressure medium.

In a preferred embodiment of the invention, the power element is formed by one or more hydraulic cylinder units.

In a preferred embodiment of the invention is a pressure-arranged's elevator minus side to the outflow opening reactor.

In another preferred embodiment of the invention there is provided at least one second force element formed by a pressure hose closed at both ends, which is arranged to return the force to the body to be tested to its basic position, and that said second force element is adjustably connected to the compressed air source either directly or using as a pressure medium.

For calibrating the measuring system of the test device, it is preferably arranged that the device comprises a force sensor with a display device, which sensor is arranged between a fixed cross-beam and a force-receiving beam articulated at one end.

The test device for venting the hydraulic system is preferably arranged in such a way that the inner surface of the upper end of the piston of the power element is formed as an upwardly tapering cone, from the upper part of which a continuously upwardly directed passage with shut-off valve is arranged.

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The device according to the invention has two force zones, the first of which makes it possible to remove the clearance quickly, and the second force zone, which has a shorter travel distance, is used for the actual test. It is possible to make the pressure and flow effect so uniform that the measuring components depending on the application become dominant. This is achieved at a substantially lower cost than known hydraulic systems. Due to the structure of the device according to the invention, the force effect is also made vibration-free even with high forces, in addition to which the device is practically silent.

In the following, the invention will be described in more detail by way of example with reference to the example shown in the accompanying drawing.

Figure 1 shows a schematic side view of a testing and quality control device according to the invention.

Figure 2 shows an enlarged side view of a schematic cross-section of the force element with its deaeration member.

The embodiment of the testing and quality control device shown in the attached figure concerns the use of the device for determining the compressive strength of concrete pieces 4. The device comprises a fixed body part, generally indicated by reference numeral 1, a movable body part or a bushing 2, means 3 for supporting the body 4 to be tested with respect to the body part 1 and a fixed hydraulic power element 5 arranged between the body part 1 and the movable body part or bumper 2. to apply a force effect to the body to be tested 4. In this application example, the force element 5 is formed by a hydraulic cylinder unit, the end of the movable piston 28 forming a buffer 2 to which the body 4 to be tested is attached by means of means not shown.

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The liquid acting as the medium of the power element 5 is connected via a pipe 16 provided with a shut-off valve 6 to the liquid space 8 of the pressure tank 7. The air space 9 of the pressure tank 7 is in turn connected to a compressed air source by a pipe 17 in which a control valve 18 and a pressure relief valve 19 are arranged.

A pressure booster 10 is connected to the force element 5 and to the pipe 16 between the closing element 6. The positive side 11 of the pressure booster 10 is connected to the pressure source via a pipe 20 provided with a flow regulator 12. A pressure booster 10 the minus side 13 of the outlet port 14 is provided with an air-permeable filter. In some embodiments, the outflow opening 14 may further be provided with a choke (not shown) for controlling the operation of the pressure booster 10 and thus also the operation of the force element 5 in the desired manner.

As can be seen from Figure 2, a continuous deaeration is provided in the power element 5. The inner surface 34 of the upper end of the piston 28 is conical so that in the system possibly. . The air enters the duct 32 arranged at the top of the conical part, which, when continuously directed upwards, continues through the shut-off valve 33 into the liquid space 8 of the pressure tank 7. The shut-off valve 33 can be opened, for example during breaks in operation, or

During the pressing step, the upper end of the body 4 to be tested rests on a plate 21 with a flat surface at its lower surface. A force sensor 25 known per se is arranged in between, which transmits an impulse to the display device 27 via a conductor 26.

i s 78559

It is possible to calibrate the press by moving the force sensor 25 in the longitudinal direction of the beam 22.

In order to return the piston 28 of the force-applying force element 5 to the test piece 4 to its basic position, a second force element 15 formed at both ends is closed by a pressure hose. The force element 15 is supported on the flat surface of the buffer 2 or fixed body part 1 relative to the piston 28 of the buffer element 5.

The power element 15 is connected via a pipe 30 to a control valve 18 and further via a pipe 17 via a pressure relief valve 19 to a source of compressed air.

The principle of operation of the device shown in the figure below is as follows.

When the control valve 18 is opened, compressed air, for example from the compressed air network, passes through the pipe 17 to the pressure relief valve. . through the brick 19 to flow into the air space of the pressure vessel 7. The pressure thus generated in the pressure vessel 7 presses the liquid in the liquid state 8 of the vessel 7 through the pipe 16 into the force element 5. The force element 5 then expands and presses the test piece 4 against the plate 21. Due to the pressure in the pipe 16 the piston 31 of the booster 10 is depressed. whereby air can escape from the positive side 11 of the booster 10. Simultaneously with the movement of the piston 31, air or alternatively liquid flows to the negative side 13 of the booster 10 through the outflow opening 14 via means not shown.

At this point, all clearances have been removed. The shut-off valve 6 in the pipe 16 is closed and compressed air is led via the pipe 20 through the flow regulator 12 to the positive side 11 of the booster 10 78559 6. In this case, the booster 10 increases the pressure in the pipe 16

Thus, during the actual testing phase, the shut-off valve 6 in the pipe 16 is closed and the movement of the force element 5 is controlled only on the plus side 11 of the pressure booster 10 by means of the compressed air supplied by the flow regulator 12. In addition to the flow regulator 12, the movement of the force element 5 can also be adjusted by means of a throttle arranged on the negative side 13 of the pressure booster.

After the test piece 4 is broken, the piston 28 of the power element 5 is returned to its initial position by opening the shut-off valve 6 and passing compressed air through the pipe 17 through the pressure relief valve 19 and the control valve 18 along the pipe 30 to the second power element 15.

The pieces of the test piece 4 can then be removed and a new test piece placed in place.

The invention has been described above with reference to only one preferred embodiment thereof. However, this is in no way intended to limit the invention to this example only, but many modifications are possible within the scope of the following claims.

Claims (6)

7 78559 1. Testing and quality control device, in particular for performing bending, tensile compression tests, the device comprising a fixed body part (1), a movable body part or a bushing (2), means (3) for supporting the body part (4) to be tested ( 1) and a hydraulically actuated force element (5) arranged between the fixed body part (1) and the movable body part or buffer (2) for applying a force to the body under test, characterized in that the fluid acting as a medium for the force element (5) is connected to a shut-off valve ( 6) through the pressure tank (7) to the liquid space (8) and the air space (9) of the tank (7) is in turn connected to a source of compressed air, and that at least one booster (10) is connected to the liquid space between the force element (5) and said shut-off valve (6). (11) is connected via a flow regulator (12) to a source of compressed air, either directly or using a liquid as a pressure medium. Device according to Claim 1, characterized in that the force element (5) is formed by one or more hydraulic cylinder units. January 3 or 2, the device according to claim, characterized in that the low side pressure booster (13) to the outflow opening (14) is arranged in the inductor. Device according to one of Claims 1 to 3, characterized in that at least one second force element (15) formed by a pressure hose closed at both ends is arranged to return the force element (5) applying force to the body to be tested (4), and that said second force element (15) is adjustably connected to the compressed air source either directly or using a liquid as a pressure medium. 8 78559 Device according to one of Claims 1 to 4, characterized in that the device comprises a force sensor (25) provided with a display device (27), which sensor is arranged on a fixed cross member (24) and a force element (5) articulated to the cross member (24) at one end. between the force receiving beam (22). Device according to one of Claims 1 to 5, characterized in that the inner surface of the upper end of the piston (28) of the power element (5) is formed as an upwardly tapering cone (34). At its upper point a continuously extending channel (33) is arranged. 32) the pressure vessel (7) into the liquid space (8). ~ 1 9 78559