SU1381358A1 - Bed for testing logging machines - Google Patents

Abstract

FIELD: forest industry. The purpose of the invention is to improve the test efficiency by increasing the test acceleration rate. The bench includes kinematically interconnected hydraulic motors 3 and 4, respectively, of the working bodies of the tested machine and the loading device. The input of the hydraulic distributor (GR) I is connected to the pump station 9, and the two outputs are connected to the high-pressure lines 5 of the hydraulic motors 3 and 4. The low-pressure pipelines 6 are connected to each other and to the make-up line 10. The third output of the GR 11 is connected to a safety valve 7 and through an additional throttle 12 with a drain tank 8. When the fluid is supplied to the hydraulic motor 3, the working member is mixed. At this time, kinematically connected to the hydraulic actuator of the working body, the hydraulic motor 4 operates in the hydraulic pump mode, sucking the fluid from the liquid pressure line 6. Next, the liquid enters the high pressure line 5 and through GR 11 to the safety valve 7, and from there through throttle 12 it is discharged into tank 8. When the working body reaches its extreme position, the limit switches are triggered, giving a signal to switch GR II. The liquid begins to flow into the hydraulic motor 4 loading device, which begins to move the working body in the opposite direction. In this case, the hydraulic motor 3 begins to operate in the hydraulic pump mode. 1 hp f-ly, 2 ill. i (L with so co 00 00

Description

The invention relates to the equipment for testing of forest machines LZM) used in the forestry industry.

The purpose of the invention is to improve the efficiency of the tests by increasing the acceleration factor in testing LZM.

FIG. 1 shows a stand, general, and its appearance; in fig. 2 - hydraulic scheme of the stand. I The test bench for logging machines contains the tested machine 1 and loading device 2, has reverse drive hydraulic motors 3 and 4 of the drive, respectively, the LZM working body and load, kinematically connected to each other, its devices with highways 5 and b, respectively, of high and low pressure, safety valve 7, drain tank 8 1- pumping station 9. High pressure lines 6 of hydraulic engines 3 and 4 are connected to a make-up line 10. The hydraulic actuator is equipped with a hydraulic distributor 11 to the throttle (filter) 12. For switching the hydraulic distributor there are limit switches 13 installed in the extreme positions of the working body 14 of the tested machine.

I stand works in the following way. I The beginning of the working stroke corresponds to the initial extreme position of the working body of the LZM under test (for example, with a cutting machine). When the 9th drive station 9 drives the working bodies of the tested machine 1 through the directional control valve 11 turned on, the working fluid enters the hydraulic motor 3 drives the working body of the machine, W it begins to mix the working or- 14. At the same time, the hydraulic drive is kinematically connected The operating unit, the hydraulic motor 4 of the loading device, operating in the hydraulic pump mode, sucks the working fluid from the low-6 & n pipeline and pumps it into the high-pressure 5, from where it is distributed 11 only enters the valve 7 and h (the choke (filter) 12 cuts into the tank 8. When the working body reaches the extreme position 14, the limit switches 13 are activated, the hydraulic valve is switched; the distributor 11 is in the third position and the liquid from the pump station 9 is fed through the distributor 11 to the hydraulic unit 4 of the loading device, which is kinematically connected with the working body 14. The hydraulic motor 4 of the loading device begins to move the working body 14 in the opposite direction, returning it to the original extreme polo living When this hydraulic 3

the drive of the working body, kinematically connected with the working body 14, begins to operate in the mode of a hydraulic pump and sucks the working fluid from line 6

low pressure, then supplies it to the high pressure line 5, from where it is fed through the valve 11, the valve 7 and the throttle (filter) 12 is fed to the tank 8. After the working body 14 reaches the

The "forward position" triggers the limit switch 13, applying a control signal to the valve P. The latter switches to the first position and the cycle repeats. Loading the tested LZM drive with variable loads is performed by sequential switching on and off of the electric control valve 7, which is controlled according to a special program from a stand-alone software device.

The feed line 10 serves to feed the working fluid of the low pressure line 6 in order to avoid premature wear of the hydraulic motors 3 and 4, cyclically alternatingly operating in the pumping mode.

5 For the drive of the working body of the machine and the loading device, for example, two hydraulic motors 3 and 4 connected in parallel can be used.

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Claims (2)

1. Test bench for logging machines, including the machine under test and loading device, which have kinematically interconnected reversible hydraulic motors 5 for driving the actuator and loading device with high and low pressure lines, safety valve, make-up line, drain tank and pumping station, characterized in that, with the aim of improving test efficiency by increasing the test acceleration factor, the hydraulic actuator is equipped with a hydraulic distributor, which inlet connected to a pumping station, and two exits to high pressure lines of the hydraulic engine of the working body and loading device, the low pressure lines of which are connected between by itself and with a make-up line, which through a safety valve is connected to the third outlet of the distributor and the drain tank through an additional choke. 2. A stand according to claim 1, wherein the safety valve is in the form of an electrically controlled relief valve. //// i ///// J FIG. one