RU2246104C9 - Load-bearing frame of testing machine - Google Patents

Abstract

FIELD: testing engineering.

SUBSTANCE: load-bearing frame of the testing machine comprises base, two hydraulic cylinders symmetrically mounted on the load-bearing axle, and connecting rods coupled with traverse. The base and bottom side of the traverse are provided with clamping devices. Two pillars are mounted on the base parallel to the rods of hydraulic cylinders, symmetrically to the load-bearing axle, and in the same plane with the axle. Two pillars are interconnected through an additional traverse at a level which is higher than the top level of the traverse connecting the hydraulic cylinders. The traverse is also mounted for permitting movement along the rods and locking in any position. The additional traverse is made for permitting movement along the pillars and locking in any position.

EFFECT: enhanced reliability of testing.

1 cl, 2 dwg

Description

The present invention relates to testing equipment, and more specifically to the structural elements of devices (power frames of testing machines) for the study of strength properties.

Known for the design of the power frames of the loading devices of testing machines, containing the base, the active beam and its drive (hydraulic or electromechanical), columns and passive beam /1...5/.

The closest analogue of the invention is the power frame produced by the state unitary enterprise "Tochmashpribor" machines: IR / 4, 5 / and its latest modification MIR-K / 5 /, presented in figure 1.

On the base 1, two hydraulic cylinders 2, the rods 3 of which are connected by a traverse 4, are placed symmetrically to the force axis. If gripping devices 5 are now fixed on the lower surface of the cross beam 4 and the base 1 of this frame, a loading device of the testing machine will be obtained, in which the base 1, rods 3 and cross beam 4 form a working space with one zone, because when the working fluid is fed into the hydraulic cylinders 2, the rods 3 and the yoke 4 will begin to move upward, loading the tensile test object installed in the gripping devices 5.

The considered power frames of the prototype are simple in design and reliable. As their undoubted merit, it is worth noting the implementation of installation moves (changing the height of the working space) and working moves with one mechanism. This makes it possible to obtain a compact, rather low-metal loading device of the testing machine. However, the power frame of the prototype has one significant drawback - using this frame, it is impossible to implement the loading device of the testing machine, which allows you to perform other than tensile types of tests.

At the same time, it is known that almost all types of metal products for quality assessment upon release from production require tensile, bending and compressive forces: for compression itself, for upsetting, and pipes for flattening, beading and distribution.

The use of two separate testing machines for performing such tests — one for tension, for example, IR / 4, 5 / or MIR-K / 5 /, the other for bending and compressive forces, for example MII / 5 /, makes these tests more expensive, and, accordingly , metal products.

In this situation, some companies go to the creation and production of plants containing two separate loading devices - one for tension and the other for bending and compressive forces, powered from one pump station and controlled by one system (for example, the MIRI-K machine, / 5 /). Such a solution only partially, to a rather small extent, eliminates the drawback noted above.

The power frame of universal machines with one central cylinder, for example, of the URS / 4 / type, requires for the transition from one type of testing to another the remounting of gripping devices and adaptation to bending or compression. This operation, especially for machines with a reproducible force of 500 kN and higher, is very laborious, requires the use of special lifting devices and is unacceptable for most factory laboratories.

The power frame with the upper arrangement of one central hydraulic cylinder and the reverse frame, which was used in the universal machines UMM / 3 /, previously produced by the Tochmashpribor software, is very bulky and metal-intensive, does not guarantee the necessary alignment of the force application and requires the use of an additional mechanism for regulating the height of the working space.

The aim of the claimed invention is a two-zone power frame, which, with good compactness and low metal consumption, allows to obtain a loading device of a testing machine with a working space having two zones - tension and compression and (or) bending, constantly prepared to perform the corresponding tests, providing with high accuracy providing wherein the axis of the test object (sample) is located on the force axis (line of action of the force).

This goal is achieved due to the fact that on the power frame containing the base, two located on this base symmetrically to the power axis of the hydraulic cylinder, the rods of which are connected by a traverse, parallel to the rods of the hydraulic cylinders are symmetrical to the power axis and two columns connected at a height are installed in one plane with it, exceeding the maximum upper position of the beam, connecting the hydraulic cylinder rods with an additional beam.

A diagram of such a power frame is shown in FIG.

On the base 1, two columns 6 are installed, passing through the holes in the traverse 4, connecting the rods 3 of the hydraulic cylinders 2 and rigidly connected at a height exceeding the maximum upper position of the traverse 4, additional traverse 7.

In the same place, in Fig. 2, the possibility of using the proposed power frame to obtain a loading device of the testing machine is shown. On the upper plane of the traverse 4 and the lower plane of the traverse 7, platforms 8 are made for testing with compressive forces or for accommodating a bending test device, and grippers are fixed to the base 1 and the lower surface of the traverse 4.

It turned out to be a compact and reliable loading device with a working space having two zones - tension and compression (or bending), constantly prepared to perform the corresponding tests, while ensuring high accuracy with the location of the axis of the sample on the force axis (force action lines). When the working fluid is fed into the hydraulic cylinders 2, the rods 3 and the connecting beam 4 will move upwards, stretching the sample installed in the gripping devices 5, or compressing (bending) the sample installed between the platforms 8.

The principle of placement on the base of the columns parallel to the hydraulic cylinder rods is symmetrical to the power axis and in the same plane as it is implemented not only according to the scheme of figure 2. The circuits shown in FIGS. 3 and 4 also comply with this principle. (The designations in FIGS. 2, 3, 4 are the same.)

The proposed design of the power frame will gain a new additional positive quality if the additional traverse is not rigidly fixed, but with the ability to move around the columns and be fixed at any point in the range of movement. This method of connecting the additional traverse 7 with the columns 6 provides the ability to change the height of the compression zone (bending), which will allow to establish the optimal working stroke during compression or bending tests and, accordingly, reduce energy consumption.

The proposed design of the power frame gains another new positive quality if the crosshead 4, connecting the rods 3 of the hydraulic cylinders 2, is also attached with the possibility of moving it along the rods and fixing at any point in the range of movement. In this case, it is possible to adjust the height of the working space of the stretch zone.

The presence of two traverses with a variable position in the power frame will allow: to obtain a loading device of the testing machine with regulation of the height of the working spaces and compression and tension, which will significantly expand the range of samples tested on such a machine. The power frame, combining all the new technical solutions, is presented in figure 5.

The mechanism for moving the traverse 4 and 7 along the rods and columns and their fixation in any position can be any, for example, according to the scheme of Fig.6. The sections of the columns (rods), within which the traverses 4 and 7 move, are made with threads on them, and the traverses themselves are fixed in place with nuts 9 and 10. In this case, for example, the traverse 7 is moved in the following manner.

A rigid spacer is installed on the compression platform 8, the crosshead 4, then, having turned on the supply of the working fluid to the hydraulic cylinders 2, the crosshead 4 is lifted up and rest against the spacer 7. Continuing to load the crosshead 7, weaken the tightening of the lower nut 10 and unscrew it on both columns. The nuts 10 are installed in a new position and, controlling the hydraulic cylinders 2, lower the yoke 7 onto the nuts 10. Then, the nuts 9 are lowered until they are in close contact with the yoke 7; again, the hydraulic cylinders 2 and the spacer on the crosshead 4 load the beam 7 and tighten the nuts 10 until they are in close contact with the beam 7. Then the load is removed and the beam 7 is tightly clamped in a new position. Similarly, using a specimen with a strength exceeding the maximum tensile strength of the loading device, the traverse 4 is rearranged.

USED SOURCES

1. Nomenclature and technical catalogs and brochures of the company Schenck, Germany.

2. Nomenclature and technical catalogs and brochures of the company MTS, USA.

3. Testing machines. The consolidated catalog of the Armavir Testing Machines Plant. 1966.

4. Testing machines. Combined catalog VO Soyuzzagranpribor. 1966.

5. Promotional brochure NIKTSIM and SPF "Tochmashpribor".

Claims (2)

1. The power frame of the testing machine, comprising a base, two symmetrical power axles of the hydraulic cylinder located on it, the rods of which are connected by a traverse, while grippers are fixed to the base and the lower surface of the crosshead, and on the base parallel to the hydraulic cylinder rods symmetrically to the power axis and in one with it two columns are installed on the plane, characterized in that the two columns installed on the base are connected by an additional traverse at a height exceeding the upper limit position of the traverse connecting the rod ki of hydraulic cylinders, which is also installed with the ability to move along the rods and fixation at any point in the gap. 2. The power frame according to claim 1, characterized in that the additional traverse is made with the possibility of movement along the columns and fixation at any point in the movement interval.

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