RU2338352C1 - Recuperative hydraulic drive of forestry assembly - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: hydraulic drive comprises hydraulic cylinder of the mounted device, drain and pressure supply lines, hydraulic cylinder of safety mechanism of tiller operation elements, hydraulic shock absorbers of running gear and spring-loaded pressure intensifier, hydraulic accumulator, hydraulic valve, pump and hydraulic reservoir. The hydraulic drive comprises also automatic overload relief valve connected with the pressure supply line by a return valve, the above supply line is connected to the hydraulic accumulator as well as to the hydraulic reservoir through the on/off control valve and safety valve.

EFFECT: reducing fuel consumption and increasing reliability of forestry assembly.

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Description

The invention relates to forestry and agricultural engineering, in particular to hydraulic drives of forestry units.

Known energy-efficient hydraulic device containing a hydraulic cylinder, drain and pressure hydraulic lines, hydraulic accumulator, valve, pump and hydraulic tank (German patent DE No. 295212, F15B 1/02, 10.24.91).

This scheme does not ensure reliable operation of the device with a decrease or absence of pressure in the accumulator.

A device for energy recovery, containing a hydraulic cylinder, drain and pressure hydraulic lines, hydraulic accumulator, valve, pump and hydraulic tank (international application PCT No. 9613669, F15В 11/064, 05/09/96).

The disadvantage of this device is its rather complicated design.

From the prototype (patent No. 2294613, АВВ 63/10, 03/10/2007, Bull. No. 7), a recuperative hydraulic drive of a tillage unit is known that contains hydraulic cylinders, a drain and pressure hydraulic lines, a hydraulic accumulator, a valve, a pump and a hydraulic tank.

However, in the indicated regenerative hydraulic drive of the tillage unit there is no hydraulic control element for automatically shutting down the tractor hydraulic pump during periods of full charge of the hydraulic accumulator, which leads to increased fuel consumption.

The invention solves the problem of reducing fuel consumption and improving the reliability of the forestry unit.

To solve this problem, a recuperative hydraulic drive of a forestry unit, including an attachment hydraulic cylinder, a drain and a pressure hydraulic line, a hydraulic cylinder of the safety mechanism of the working bodies of the tillage implement, hydraulic shock absorbers of the chassis and a spring-loaded pressure multiplier, a hydraulic accumulator, a valve, a pump and a hydraulic tank, according to the invention, additionally unloading automatic valve connected through a check valve with a pressure head the line connected to the hydraulic accumulator and through the on-off distributor and safety valve to the hydraulic tank.

The drawing shows a diagram of a regenerative hydraulic drive of a forestry unit.

The recuperative hydraulic drive of the forestry unit consists of recuperative systems 1, 2, 3, sections of the hydrodistributor 4 and the pump and accumulator unit 5. The recuperative system 1 of the safety mechanism of the working bodies of the tillage implement includes a hydraulic cylinder 6, an adjustable throttle 7, check valves 8 and 9. Recuperative system 2 the tractor’s chassis includes a hydraulic shock absorber 10, a throttle 11 and check valves 12, 13, 14, 15. The regenerative system 3 of the tractor’s outboard mechanism consists of a hydraulic cylinder 16, under the spring pressure multiplier 17 and the check valves 18, 19. The pump-accumulator unit 5 includes a pump 20, a hydraulic tank 21, a filter 22, a check valve 23, a hydraulic accumulator 24, a pressure gauge 25 and an unloading automatic valve 26, which, in turn, includes a check valve valve 27, on-off valve 28 and pressure relief valve 29. All hydraulic drive systems are interconnected by pressure 30 and drain 31 hydraulic lines.

The work of the regenerative hydraulic drive of the forestry unit is based on the pumping effect and is as follows. When the forestry unit moves on forest or agricultural facilities, the tractor undergoes vertical movements under the influence of its mass and roughness of the supporting surface, as a result of which the pistons of the hydraulic shock absorbers 10 make reciprocating movements. In this case, the movement of the piston to the left is accompanied by the displacement of part of the working fluid from the shock cavity of the shock absorber through the throttle 11 and the check valve 15 to the pressure hydraulic line 30, thus recharging the hydraulic accumulator 24. At the same time, due to the discharge, the rod cavity of the shock absorber 10 is filled with the working liquid from the hydraulic tank 21 through the drain hydraulic line 31 and the check valve 12. Similarly, when the shock absorber piston 10 moves to the right, the working fluid is displaced from the rod cavity into the hydraulic accumulator 24 through the non-return valve 13 and the discharge hydraulic line 30, and the stock cavity, due to the discharge, is filled with the working fluid from the hydraulic tank 21 through the drain hydraulic line 31 and the non-return valve 14.

In the event that the tillage implement encounters an obstacle, the safety mechanism is activated and the stand with working bodies deviates upward relative to the implement frame. In this case, the piston of the hydraulic cylinder 6 of the safety mechanism displaces the working fluid from the bolt cavity through the check valve 8 and partially through the adjustable throttle 7 to the pressure hydraulic line 30 and hydraulic accumulator 24. After overcoming the obstacle, the working bodies return to their original position by the pressure of the working liquid in the pressure hydraulic line entering hydraulic cylinder 6 through an adjustable throttle 7. With a sharp return of the working bodies to their original position under the action of their own mass in the stock of the cylinder 6 at the initial moment, the formation of a discharge of the working fluid is possible. To eliminate it, check valve 9 is used.

When the forestry unit is moving, the mounted tillage implement in the transport position creates significant alternating moments relative to the hinges of the attachment of the links of the mounted mechanism to the tractor frame, causing the implement to oscillate in the vertical and horizontal planes. In this case, the loads on the construction elements of the mounted mechanism are reduced and energy is accumulated using a spring-loaded pressure multiplier 17 and check valves 18 and 19. In this case, the oscillations of the gun, through the links of the mounted mechanism, are transmitted to the piston of its hydraulic cylinder 16, and the piston, despite being locked the spool device of the hydraulic distributor 4 both cavity of the hydraulic cylinder, also makes minor fluctuations. The magnitude of these fluctuations is prudently ensured by the selected spring spring pressure multiplier 17 and partially by the compressibility of the working fluid in the cavities and flexible hoses of the hydraulic cylinder 16 of the mounted mechanism. When the piston of the hydraulic cylinder 16 downward, the working fluid is displaced from its rod cavity into the cavity of the larger diameter of the multiplier 17. The piston and the rod of the multiplier, overcoming the force of the pre-pressed spring, also move down and displace the compressed working fluid from the cavity of the smaller diameter of the multiplier through the check valve 18 and the pressure head hydraulic line 30 to the hydraulic accumulator 24. When the piston of the hydraulic cylinder 16 moves up, the piston and the multiplier rod, under the influence of a previously compressed spring, move up. The resulting pressure in the cavity of a smaller diameter of the multiplier 17 is eliminated using the check valve 19.

When moving from a transport position to a working, mounted mounted tillage implement, it falls down with some acceleration due to its mass. At this moment, the working fluid is displaced from the rear cavity of the hydraulic cylinder 16 of the tractor attachment mechanism both into the drain hydraulic line through the spool device of the hydraulic distributor 4, and into the cavity of the larger diameter of the multiplier 17. As in the previous case, the piston and rod of the multiplier move down and displace the compressed working fluid through the check valve 18 and the pressure hydraulic line 30 into the hydraulic accumulator 24.

During periods of full charging of the hydraulic accumulator 24, an unloading automatic valve 26 is activated, which is designed to automatically transfer the pump to idle mode when there is no energy consumption by the hydraulic system and recharge the hydraulic accumulator 24 when the pressure in it decreases to a certain value.

In the process of operation of the forestry unit, the protection of the regenerative hydraulic actuator from exceeding a predetermined pressure value, with a fully charged hydraulic accumulator 24, is carried out using a safety valve 29.

Thus, the recuperative hydraulic drive reduces the fuel consumption of the forestry unit by accumulating in the hydraulic shock absorbers and returning to the hydraulic system of the unit unproductive loss of energy from vertical movements of the sprung tractor mass when the tractor springs up, the hydraulic safety mechanism of the tillage implement, and also due to damping of the working fluid in the hydraulic cylinder of the mounted mechanism in the transport position of the implement when the tractor is moving and when lowering the mounted implement to the working position. In addition, due to a significant decrease in the maximum "peak" pressure values in the regenerative hydraulic drive due to the use of a hydraulic accumulator in it, the loads on the structural elements during the operation of the forestry unit are reduced and, thereby, its reliability is increased.

Claims (1)

Recuperative hydraulic drive of the forestry unit, including the mounted hydraulic cylinder, drain and pressure hydraulic lines, the hydraulic cylinder of the safety mechanism of the working bodies of the tillage implement, the hydraulic shock absorbers of the undercarriage and the spring-loaded pressure multiplier, hydraulic accumulator, hydraulic distributor, pump and hydraulic tank, characterized in that it contains an unloading valve connected via a check valve to a pressure hydraulic line in communication with a hydraulic the battery and through the on-off distributor and the safety valve with a hydraulic tank.