CN205329745U - Two operation mode control systems of leveler - Google Patents

Abstract

The utility model belongs to the technical field of engineering machinery, in particular to a dual-operation mode control system for a grader. Including steering hydraulic circuit, brake hydraulic circuit, left working hydraulic circuit and right working hydraulic circuit; the steering hydraulic circuit includes steering pump, steering priority valve, steering gear and steering hydraulic cylinder, and the braking hydraulic circuit includes brake pump, filling fluid Valve, brake pedal valve, brake accumulator and brake hydraulic cylinder, the left and right working hydraulic circuits include their own working pumps, control valves and multiple actuators; also include the mode selection valve, the EF port of the steering priority valve passes through The pipeline is connected to the mode selection valve, and then connected to the oil inlet of the right control valve through the pipeline, and the N port of the filling valve is connected to the mode selection valve through the pipeline, and then connected to the oil inlet of the left control valve through the pipeline . Through the above-mentioned mode selection valve, the dual-mode operation of the motor grader operation system is realized, that is, the fast operation mode with large flow rate and the precise operation mode with small flow rate.

Description

A dual-operation mode control system for a motor grader

technical field

The utility model belongs to the technical field of engineering machinery, in particular to a dual-operation mode control system for a grader.

Background technique

In construction machinery, independent steering, braking and working hydraulic circuits are mostly used. All three hydraulic circuits are powered by independent hydraulic pumps (the series pumps currently used in motor graders are essentially two or more independent hydraulic pumps connected in series). Such mutually independent hydraulic circuits have situations such as insufficient use of engine power, inability of various hydraulic systems to work together, and partial power waste, which cannot realize the conversion of the multi-working mode of the motor grader. The utility model is based on the hydraulic circuit of the existing independent brake pump, steering pump and working pump of the grader, and uses combined hydraulic valve elements to solve the cooperative work of multiple pumps, and realizes two flow pressure modes of the working hydraulic circuit—that is, large flow Work in dual mode of low pressure and small flow high pressure mode.

Utility model content

In order to solve the technical problems existing in the known technology, the utility model provides a dual-operation mode control system for graders, which realizes the dual-mode operation of the operation hydraulic circuit in two flow pressure modes (i.e. high-flow low-pressure mode and low-flow high-pressure mode). , Reduce the hydraulic installed power of the whole machine, increase the working speed of the oil cylinder, and increase the maximum working pressure.

The technical solution adopted by the utility model to solve the technical problems existing in the known technology is: a dual-operation mode control system of a grader includes a steering hydraulic circuit, a brake hydraulic circuit, a left operation hydraulic circuit and a right operation hydraulic circuit;

The steering hydraulic circuit includes a steering pump, a steering priority valve, a steering gear and a steering hydraulic cylinder. The oil inlet of the steering pump is connected to the hydraulic oil tank through a pipeline, and the oil outlet is connected to the oil inlet of the steering priority valve through a pipeline. The steering priority The oil outlet of the valve is connected to the oil inlet of the steering gear through the pipeline, and the oil outlet of the steering gear is connected to the steering hydraulic cylinder through the pipeline;

The brake hydraulic circuit includes a brake pump, a filling valve, a brake pedal valve, a brake accumulator and a brake hydraulic cylinder. The oil inlet of the brake pump is connected to the hydraulic oil tank through a pipeline, and the oil outlet is connected through a pipe The oil outlet of the oil charging valve is connected to the oil inlet of the brake accumulator through the pipeline, and the oil outlet of the brake accumulator is connected to the brake hydraulic pressure through the pipeline. cylinder, the brake pedal valve is connected to the pipeline between the oil outlet of the charging valve and the oil inlet of the brake accumulator;

The left working hydraulic circuit includes a left valve working pump, a left steering valve and multiple left actuators. The oil inlet of the left valve working pump is connected to the hydraulic oil tank through a pipeline, and the oil outlet is connected to the oil inlet of the left steering valve through a pipeline. The oil outlet of the left control valve is connected to each left actuator through pipelines;

The right operation hydraulic circuit includes the right valve operation pump, the right control valve and multiple right actuators. The oil inlet of the right operation pump is connected to the hydraulic oil tank through the pipeline, and the oil outlet is connected to the oil inlet of the right control valve through the pipeline. The oil outlet of the right control valve is connected to each right actuator through pipelines;

It also includes a mode selection valve. The EF port of the steering priority valve is connected to the mode selection valve through a pipeline, and then connected to the oil inlet port of the right control valve through a pipeline. The N port of the filling valve is connected to the mode selection valve through a pipeline. It is then connected to the oil inlet of the left control valve through a pipeline.

The advantages and positive effects of the utility model are: the utility model provides a dual-operation mode control system of a motor grader with reasonable structural design. Compared with the existing control system, the system is independent of steering, braking and operation hydraulic circuits Oil-fed open hydraulic system. By adding a mode selection valve on the basis of the original hydraulic system of the grader, the dual-mode operation of the grader operation system can be realized. The dual-mode operation can realize the fast operation of large flow and the precise operation mode of small flow. Since the system realizes the combined operation of the steering system and the braking system, the displacement of the operating pump can be reduced while the total installed flow remains unchanged, which can not only increase the operating pressure but also reduce the installed power of the hydraulic system of the whole machine. To achieve the effect of energy saving. The mode selection valve has the advantages of simple structure, small size, high integration, and convenient installation and maintenance.

Preferably: the mode selection valve includes two sets of electromagnetic reversing valves, relief valves and one-way valves arranged side by side, wherein one set of electromagnetic reversing valves, relief valves and one-way valves are located between the EF port of the steering priority valve and the right control Between the oil inlets of the valves, another set of electromagnetic reversing valves, overflow valves and check valves are located between the N port of the filling valve and the oil inlet of the left control valve.

Description of drawings

Fig. 1 is the structural representation of the utility model.

In the figure: 1. Hydraulic oil tank; 2. Steering pump; 3. Brake pump; 4. Left valve operating pump; 5. Right valve operating pump; 6. Steering priority valve; 7. Steering gear; 8. Steering hydraulic cylinder; 9. Mode selection valve; 9.1. Electromagnetic reversing valve; 9.2. Relief valve; 9.3. Check valve; 10. Filling valve; 11. Brake pedal valve; 12. Brake accumulator; 13. Hydraulic cylinder; 14, left control valve; 15, right control valve; 16, left actuator; 17, right actuator.

detailed description

In order to further understand the content of the invention, features and effects of the present utility model, the following examples are given in detail as follows:

Please refer to Fig. 1, the utility model uses an open hydraulic system, including a steering hydraulic circuit, a brake hydraulic circuit, a left working hydraulic circuit and a right working hydraulic circuit, wherein the steering hydraulic circuit is used to control the steering of The hydraulic circuit is used to control the brake of the grader, and the two working hydraulic circuits are used to control the working device of the grader.

The steering hydraulic circuit includes a steering pump 2, a steering priority valve 6, a steering gear 7, and a steering hydraulic cylinder 8. The oil inlet of the steering pump 2 is connected to the hydraulic oil tank 1 through a pipeline, and the oil outlet is connected to the steering priority valve 6 through a pipeline. The oil inlet of the steering priority valve 6 is connected to the oil inlet of the steering gear 7 through a pipeline, and the oil outlet of the steering gear 7 is connected to the steering hydraulic cylinder 8 through a pipeline.

The brake hydraulic circuit includes a brake pump 3, a filling valve 10, a brake pedal valve 11, a brake accumulator 12 and a brake hydraulic cylinder 13, and the oil inlet of the brake pump 3 is connected to the hydraulic oil tank through a pipeline 1. The oil outlet is connected to the oil inlet of the filling valve 10 through a pipeline, and the oil outlet of the filling valve 10 is connected to the oil inlet of the brake accumulator 12 through a pipeline, and the oil outlet of the brake accumulator 12 The oil outlet is connected to the brake hydraulic cylinder 13 through a pipeline, and the brake pedal valve 11 is connected to the pipeline between the oil outlet of the filling valve 10 and the oil inlet of the brake accumulator 12 .

The left operation hydraulic circuit includes a left valve operation pump 4, a left control valve 14 and a plurality of left actuators 16. The oil inlet of the left valve operation pump 4 is connected to the hydraulic oil tank 1 through a pipeline, and the oil outlet is connected to the left hydraulic tank 1 through a pipeline. The oil inlet of the steering valve 14 and the oil outlet of the left steering valve 14 are connected to each left actuator 16 through pipelines.

The right operation hydraulic circuit includes a right valve operation pump 5, a right control valve 15 and a plurality of right actuators 17. The oil inlet of the right valve operation pump 5 is connected to the hydraulic oil tank 1 through a pipeline, and the oil outlet is connected to the right side through a pipeline. The oil inlet of the steering valve 15 and the oil outlet of the right steering valve 15 are connected to each right actuator 17 through pipelines.

It also includes a mode selection valve 9, the EF port of the steering priority valve 6 is connected to the mode selection valve 9 through a pipeline, and then connected to the oil inlet of the right control valve 15 through a pipeline, and the N port of the filling valve 10 is connected through a pipeline To the mode selection valve 9, and then connected to the oil inlet of the left control valve 14 through a pipeline.

In this embodiment, the mode selection valve 9 includes two groups of electromagnetic reversing valves 9.1, overflow valves 9.2 and check valves 9.3 arranged side by side, wherein one set of electromagnetic reversing valves 9.1, overflow valves 9.2 and one-way valves 9.3 are located at Between the EF port of the steering priority valve 6 and the oil inlet port of the right steering valve 15, another group of electromagnetic reversing valve 9.1, overflow valve 9.2 and check valve 9.3 are located between the N port of the filling valve 10 and the left steering valve 14 between the oil inlets.

work process:

The steering pump 2 sucks oil from the hydraulic oil tank 1, and forms a steering hydraulic circuit through the steering priority valve 6, the steering gear 7 and the steering hydraulic cylinder 8. The brake pump 3 absorbs oil from the hydraulic oil tank 1, fills the brake accumulator 12 through the filling valve 10, and the brake pedal valve 11 outputs the pressure of the brake accumulator 12 to the wheel brake hydraulic cylinder 13 to form Brake hydraulic circuit. The left valve operating pump 4 and the right valve operating pump 5 suck oil from the hydraulic oil tank 1, and provide power for the left actuator 16 and the right actuator 17 through the left operating valve 14 and the right operating valve 15 respectively to form two left and right operating hydraulic circuits.

When there is no steering action, the pressure oil provided by the steering pump 2 enters the mode selection valve 9 through the output of the EF port of the steering priority valve 6 . Similarly, when the brake pump 3 finishes filling the brake accumulator 12 , the pressure oil provided by the brake pump 3 is output through the N port of the filling valve 10 and enters the mode selection valve 9 .

When the solenoid valve reversing valve 9.1 in the mode selection valve 9 is de-energized, the steering pressure oil and brake pressure oil entering the mode selection valve 9 are unloaded and flow back to the hydraulic oil tank 1. At this time, the steering pump 2 and brake The hydraulic oil output by the dynamic pump 3 does not participate in the confluence of the working hydraulic system, and the motor grader is in a fine working mode in which only the left valve working pump 4 and the right valve working pump 5 participate.

When the electromagnetic reversing valve 9.1 in the mode selection valve 9 is energized and works, the electromagnetic reversing valve 9.1 cuts off the passage of the steering system fluid and the braking system fluid entering the mode selection valve 9 from flowing back to the hydraulic oil tank 1 . The pressure oil output by the steering pump 2 and the brake pump 3 is combined with the pressure oil output by the right valve operating pump 5 and the left valve operating pump 4 respectively. At this time, the working hydraulic system of the grader increases the working flow, and the grader is in the high-flow fast operation mode.

The pressure setting value of the overflow valve 9.2 in the mode selection valve 9 is lower than the maximum working pressure of the working hydraulic system. When working in the high-flow fast operation mode, when the movement of the actuator is at the end or encounters a large resistance to make the pressure of the working hydraulic system rise to the set value of the relief valve 9.2, the relief valve 9.2 in the mode selection valve 9 is at The unloading is opened under the feedback of the downstream pressure signal of the one-way valve 9.3. At this time, the pressure oil of the steering system and the pressure oil of the braking system flowing into the mode selection valve 9 are unloaded and flow back to the hydraulic oil tank 1. The working hydraulic system is only continuously supplied with oil by the left valve working pump 4 and the right valve working pump 5, and the pressure continues to rise. The working hydraulic system of the motor grader automatically switches to the low-flow high-pressure working mode, which can effectively protect the steering system and braking system . Automatic adjustment of flow and pressure according to load changes can also effectively utilize engine power and prevent overloading and power waste.

In this system, the steering priority valve 6 ensures that the pressure oil supply of the steering system is prioritized when the vehicle has a steering demand, and the filling valve 10 also prioritizes the pressure reserve of the brake accumulator 12 in the braking system.

Claims (2)

1. A dual-operation mode control system for a motor grader, characterized in that it includes a steering hydraulic circuit, a brake hydraulic circuit, a left operation hydraulic circuit and a right operation hydraulic circuit; The steering hydraulic circuit includes a steering pump (2), a steering priority valve (6), a steering gear (7) and a steering hydraulic cylinder (8). The oil inlet of the steering pump (2) is connected to the hydraulic oil tank (1), The oil outlet is connected to the oil inlet of the steering priority valve (6) through a pipeline, and the oil outlet of the steering priority valve (6) is connected to the oil inlet of the steering gear (7) through a pipeline, and the oil outlet of the steering gear (7) The oil outlet is connected to the steering hydraulic cylinder (8) through a pipeline; The brake hydraulic circuit includes brake pump (3), filling valve (10), brake pedal valve (11), brake accumulator (12) and brake hydraulic cylinder (13), brake pump (3 )’s oil inlet is connected to the hydraulic oil tank (1) through a pipeline, the oil outlet is connected to the oil inlet of the filling valve (10) through a pipeline, and the oil outlet of the filling valve (10) is connected to The oil inlet port of the brake accumulator (12), the oil outlet port of the brake accumulator (12) is connected to the brake hydraulic cylinder (13) through pipelines, and the brake pedal valve (11) is connected to On the pipeline between the oil outlet of the valve (10) and the oil inlet of the brake accumulator (12); The left working hydraulic circuit includes a left valve working pump (4), a left control valve (14) and a plurality of left actuators (16), and the oil inlet of the left valve working pump (4) is connected to the hydraulic oil tank (1) through a pipeline , The oil outlet is connected to the oil inlet of the left control valve (14) through the pipeline, and the oil outlet of the left control valve (14) is connected to each left actuator (16) through the pipeline; The right working hydraulic circuit includes a right valve working pump (5), a right control valve (15) and a plurality of right actuators (17), and the oil inlet of the right valve working pump (5) is connected to the hydraulic oil tank (1) through a pipeline , The oil outlet is connected to the oil inlet of the right control valve (15) through the pipeline, and the oil outlet of the right control valve (15) is connected to each right actuator (17) through the pipeline; It also includes a mode selection valve (9), the EF port of the steering priority valve (6) is connected to the mode selection valve (9) through a pipeline, and then connected to the oil inlet of the right control valve (15) through a pipeline, and the filling valve The N port of (10) is connected to the mode selection valve (9) through a pipeline, and then connected to the oil inlet of the left control valve (14) through a pipeline. 2. The dual-operation mode control system of the motor grader according to claim 1, characterized in that: the mode selection valve (9) includes two sets of electromagnetic reversing valves (9.1), overflow valves (9.2) and one-way valves arranged side by side. valve (9.3), a set of electromagnetic reversing valve (9.1), relief valve (9.2) and check valve (9.3) are located at the EF port of the steering priority valve (6) and the oil inlet port of the right steering valve (15) Between, another group of electromagnetic reversing valve (9.1), relief valve (9.2) and check valve (9.3) are located between the N port of the charging valve (10) and the oil inlet of the left control valve (14) .