Tractor direction valve


Direction valve is one of the important control components in the hydraulic system, which is mainly used to control the flow direction of hydraulic oil and realize the connection and isolation between hydraulic components. In hydraulic systems, the direction valve is usually used to control the direction of action of the action mechanism of unidirectional motion, so that it moves according to a predetermined path and speed. At the same time, the Direction Valve can also control the flow rate according to the different oil pressure, so the Direction Valve plays a very important role in the hydraulic system.


First. The structure of the Tractor direction valve

The Tractor direction valve consists of a control valve body, gears, gear shaft, piston, and hydraulic cylinders. The Direction valve is divided into front and rear oil circuits, and the high-pressure oil flow is introduced into the pressure oil chamber through the hydraulically controlled check valve by controlling the operation of the valve body, so that the piston moves along the axis under the action of pressure, and the gear shaft is meshed with the gear on the power take-off shaft to achieve the purpose of the tractor moving forward or backward.


Second. Workflow of the Tractor direction valve

1. Forward state:

When the tractor is in the forward state, the operating mechanism of the control valve body makes the high-pressure oil flow from the hydraulic pump enter the front oil circuit through the control valve in the reversing valve, and the piston is driven to move to the left, and the planetary gear on the gear shaft rotates to the left at this time, and the power is transmitted to the power take-off shaft in the process of meshing with the planetary gear on the power take-off shaft, and the wheel is driven forward.

2. Regressive state:

When the tractor needs to reverse, the operating mechanism switches the control valve in the control valve body to the rear oil circuit, that is, controls the high-pressure oil flow into the rear oil circuit of the direction valve, and makes the piston move to the right. At this time, the planetary gear on the gear shaft rotates to the right, and the power is output to the wheel in the reverse during the process of meshing with the planetary gear on the PTO shaft to realize the backwardness of the tractor.


Third. The role of the various components of the Tractor direction valve

1. Hydraulic pump: provide high pressure hydraulic oil.

2.direction valve: switch the front oil circuit and the rear oil circuit.

3. Hydraulically controlled check valve: the liquid flows to the pressure oil chamber under the action of pressure to prevent it from entering the reverse oil circuit.

4. Hydraulic cylinder: converts the thrust of the pressure oil into mechanical energy to push the piston to move.

5. Gear shaft: output power to power take-off shaft.


As an important component of the tractor drive system, the working principle of the Tractor direction valve and the role of each component are very important. Understanding how the Direction Valve works helps to have a deeper understanding of how the tractor's drivetrain works, so that the tractor can be better maintained.


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