SU1606749A1 - Rig for determining starting characteristics of hydraulic units - Google Patents

Abstract

The invention can be used in testing hydromotors to determine starting characteristics. The aim of the invention is to extend the functionality when creating constant or variable dynamic loads on the motor shaft. The test bench contains the hydraulic motor 1 under test, the pressure cavity of which is connected by hydraulic line 2 via adjustable throttle 3 to hydraulic pump 4, load hydraulic actuator in the form of hydraulic cylinder 6 to the power supply system from hydraulic pump 7. On the shaft of hydraulic motor 1, the flywheel 11 and drum 14 connected by flexible wiring 15 are fixed the piston rod 16 of the piston 17 of the hydraulic cylinder 6 directly or through the block 18. By changing the flow area of the throttles 8, the pressure in the line 10 and the torque on the drum 14 are controlled, setting the load in rotation angle of the shaft. 1 il.

Description

The invention relates to machine-building hydraulics and can be used in testing hydraulic motors to determine the starting characteristics, the time of breaking.

The aim of the invention is to expand the functionality when creating constant or variable dynamic loads on the shaft of the hydraulic motor.

The drawing shows a schematic diagram of the proposed stand.

The stand contains the tested hydraulic motor 1, the pressure cavity of which is connected by a hydraulic line 2 through an adjustable throttle 3 with a hydraulic pump 4 and a safety valve 5, a load hydraulic actuator. made in the form of a hydraulic cylinder 6 with a hydraulic pump power system 7, a control system in the form of an adjustable throttle 8 and a safety valve

9 connected to the pressure line

10. A flywheel 11, torque sensors 12 and revolutions and a drum 14 are connected to the output shaft of the hydraulic motor 1, connected via flexible wiring 15 to the piston rod 16 of the piston 17 of the loading hydraulic cylinder 6 directly with low-speed hydraulic motors 1 or through block 18 when installing high-speed hydraulic motors 1.

The stand is equipped with a system 19 for recording parameters associated with sensors of torque 12, speed 13 and pressure 20 installed in the hydraulic line 2.

The stand works as follows.

Select the operating mode of the loading hydraulic cylinder 6: the constant load mode on the shaft of the tested hydraulic motor 1 with the throttle 8 fully closed, or the mode of increasing load (when starting the fan drive) when the passage of the throttle 8 decreases, or the falling load mode (tests according to GOST 20719-80 ) when increasing the flow area of the inductor 8, or variable load mode.

In constant load mode, the safety valve 9 is adjusted to the required pressure, while the starting torque of the load on the drum 14 overcome by the test motor 1 will be equal to the product of the tension force of the cable 15 by the radius of winding of the drum 14. The tension of the cable 15 when fixing it directly to the rod 16 depends on the effective area of the piston 17 and the pressure setting of the safety valve 9. The use of block 18 allows to increase the time for determining the starting characteristics with a constant stroke of the rod 16 and d ametre drum 14. When setting of the safety valve 9 is necessary to consider the multiplicity of unit 18. When the hydraulic pump 7, working fluid is supplied through the pressure line 10 to the rod end of the hydraulic cylinder 6. The throttle 8 is closed. The piston 17 occupies the extreme (lower) position. The working fluid from the hydraulic pump 4 is fed into the pressure chamber of the tested hydraulic motor 1 and as soon as the moment developed by the hydraulic motor 1 exceeds the load moment on the drum 14, the shaft of the hydraulic motor 1 will begin to rotate and the cable 15 will be wound on the drum 14. The parameters are measured. The piston 17 of the hydraulic cylinder 6 moves upward and the working fluid from the rod cavity is displaced into> line 10 to drain through valve 9. In this case, the hydraulic system of the loading device operates in constant pressure mode. When the piston 17 is in the upper position of the hydraulic cylinder 6, the pressure in the pressure chamber of the tested hydraulic motor 1 increases to the setting of the safety valve 9, it opens and the hydraulic motor stops.

In the modes of increasing or decreasing loads · the operation of the stand differs by the supply of a control, for example, an electric signal to the adjustable throttle 8 with the valve 9 closed. At the same time, an increase in the orifice of the throttle 8 causes a decrease in pressure in line 10, and therefore, load on the drum 14. Decrease the flow area of the throttle 8 increases the pressure in the line 10 and the moment on the drum 14.

The stand provides a mode of setting a constant load by the angle of rotation of the shaft.

Claims (1)

Claim A stand for determining the starting characteristics of hydraulic units containing a test hydraulic motor, the pressure cavity of which is connected through an adjustable throttle to a hydraulic pump and a safety valve, -. hydraulic loading actuator, pressure sensor, parameter registration system, flywheel and measurement system, including torque and speed sensors, mounted on the output shaft of the hydraulic motor, which is kinematically connected to the hydraulic loading actuator having a power supply, control system and safety valve, 1606749 6 characterized in that ', in order to expand the functionality when creating constant or variable dynamic loads on the motor shaft, the load hydraulic drive is made in the form of a hydraulic cylinder, the output shaft of the hydraulic motor is equipped with a drum connected by flexible wiring through the chain hoist to the load hydraulic drive rod, while .In the control system includes an adjustable throttle.