SU1541427A1 - Rig for service-life testing of swivel hydraulic cylinders - Google Patents

Abstract

The invention can be used to conduct life tests of swinging cylinders with a constant load. The aim of the invention is to enhance the functionality and simplify the design of the stand. The stand contains a bed 3 with a rocking lever 4 fixed on it by means of a hinge 5, a rocking test 6 and a load 7 hydraulic cylinders, the rodless cavities of which are hydraulically connected by line 8 and connected via valves 9 and 10 respectively to pump 1 and tank 2, and the rod cavities are communicated hydraulic lines 11 and 12 through a three-position control valve 13. The rods of the hydraulic cylinders 6 and 7 are fixed on the swing arm 4 on the hinge 16 and are arranged normally to each other in their extreme positions, and the axis of the hinge 5 is equidistant from the axes hinges 14 and 15 for fastening the housings of hydraulic cylinders 6 and 7 on the bed 3. In this case, it is possible to create maintaining high working pressure in the hydraulic cylinders and large forces on the rods with minimal energy consumption. 2 Il.

Description

The invention relates to engineering hydraulics and is intended to carry out life tests of oscillating identical hydraulic cylinders with a constant load.

The purpose of the invention is to expand the functionality and simplify the design of the stand.

FIG. 1 shows the general scheme of the stand; in fig. 2 shows a kinematic scheme for mounting swiveling hydraulic cylinders with a lever.

The stand for endurance tests of swinging hydraulic cylinders with a constant load contains a pump 1, a tank 2, a frame 3 with swings levers 4 fixed on it by means of a hinge 5, a swinging test 6 and a load 7 hydraulic cylinders, rodless cavities - which are hydraulically joined by line 8 and connected through valves 9 and 10, respectively, with the pump 1 and tank 2, and the rod cavities are communicated hydraulically by lines 11 and 12 through a three-position control valve 13 with the pump 1 and tank 2. The housings of the hydraulic cylinders 6 and 7 are fixed on the base 3 through ohm hinges 14 and 15, and the rods of the hydraulic cylinders 6 and 7 - by a swing arm 4 by a common pivot 16, the axis of which is located on the shoulder, the magnitude of which is determined from the kinematic scheme of the stand according to the formula

50

R. Ut ± lUitg3: lk ± 4gIi.3: & llll- ± -Iilt

4-f 21, U

where 1 (- shoulder of the test cylinder 6 with the extreme retracted position of its stem;. shoulder of the load cylinder 7 with the extreme extended position of its stem. The rods of the hydraulic cylinders 6 and 7 are arranged normally to each other in the extreme - 5 their positions, and the hinge axis 5 of the mount swing lever 4 on bed 3 equidistant from hinge axes

15

20

25 30 35 40

45

50

- 5 14 and 15 mounting housings of hydraulic cylinders 6 and 7. The right angle between the rods is selected from the conditions of the minimum dimensions of the stand and the assembly of two hydraulic cylinders 6, 7 and swing lever 4, With the swing lever 4 vertical, the shoulders of hydraulic cylinders 6 and 7 are equal - (1D + 1).

The swing lever 4 can be equipped with limit switches providing automatic control. the position of the hydraulic distributor 13.

The stand works as follows.

When the working fluid is supplied from the pump 1 through the open valve 9 and line 8 into the rodless cavities of the test 6 and load 7 swinging cylinders, a preliminary high pressure is created with the valve 10 closed, after which the valve 9 closes. At the same time, the neutral distributor 13 communicates the lines 11 and 12 of the rod cavities of the hydraulic cylinders 6 and 7 with the drain line to the tank 2.

When the control signal is applied to the hydraulic distributor 13, it is shifted to one of the extreme positions, thereby connecting the pressure line of the pump 1 via line 12 to the rod of the loading hydraulic cylinder J, and the rod of the test cylinder 6 through the hydraulic line 11 communicates with the drain into the tank 2. When this happens, the stem of the load cylinder 7 is pushed back and, accordingly, the rod of the test cylinder 6. is extended.

The movement of the rods of the hydraulic cylinders 6 and 7 is reversed when they reach the opposite extreme position, the swing lever switches the limit switch, the control signal from which the hydraulic distributor 13 is shifted to another extreme position, which prevents the swing lever 20 from operating a common hinge, the axis of which, at the eccentric moment of the bending moment, is located on the shoulder of the swinging rod fastening to the lever lever, the lever (R) determined by the formula

and no manufacturing is required

special loading hydraulic cylinder. The presence of internal and external 25 leakage of working fluid is not tolerated; UL ± l "lL ± 21i. L2. ± lllLlЈ Ш ± Ш, and

where 1 is the shoulder of the test cylinder with the extreme retracted position of its rod; - the shoulder of the hydraulic cylinder with the extreme extended position of its stem, while the axis of the pivotal attachment of the swinging arm on the frame is equidistant from the axes of the pivotal attachment of the hydraulic cylinders.

otherwise, loss of tightness is a rejection sign of the hydraulic cylinders.

Claims (1)

Claims of the Invention Stand for durability testing of swinging cylinders with a constant load, comprising a pump, a tank, a frame with a hinged lever attached to it by a swinging lever, equipped with ; UL ± l "lL ± 21i.l2. ± lllLlЈ Ш ± Ш, and where 1 is the shoulder of the test cylinder with the extreme retracted position of its rod; - the shoulder of the hydraulic cylinder with the extreme extended position of its stem, while the axis of the pivotal attachment of the swinging arm on the frame is equidistant from the axes of the pivotal attachment of the hydraulic cylinders. ®ig