Tractor direction valve


1. The composition of the Tractor Direction Valve

The Tractor Direction Valve consists of components such as a control valve body, gears, gear shafts, pistons, and hydraulic cylinders. The Tractor 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. The Direction Valve is a commonly used element in hydraulic systems and is a key component in achieving steering. Its main function is to realize the steering control of the equipment by controlling the flow direction of the hydraulic oil. Specifically, the Direction Valve directs hydraulic oil from one oil circuit to another, allowing the equipment to steer. In hydraulic systems, the Direction Valve is generally used as a control element, which can be used to control the steering operation of actuators such as hydraulic cylinders and hydraulic motors.

2. How the direction valve works

The working principle of the direction valve is to rely on the movement of the valve core in the valve body to control the connection and shut-off between different oil circuits. Typically, a direction valve consists of a body and a spool. There are multiple oil circuits inside the valve body, and when the valve core moves in the valve body, it can be connected with different oil circuits to control the hydraulic flow direction to achieve steering.

The valve core of the Direction Valve is usually composed of springs, sealing rings and cone holes, etc., and its working process is divided into two states: open and closed. When the spool is closed, hydraulic fluid flows through the inlet into the steering valve, but cannot flow out. When the spool is pushed to the open position, the hydraulic oil can flow smoothly from the inlet to the other oil circuits in the valve body, allowing the equipment to be steered.

3. Workflow of 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 go backwards, the operating mechanism switches the control valve in the control valve body to the rear oil circuit, that is, the control of the high-pressure oil flow into the rear oil circuit of the reversing valve, so that the piston moves 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.

4. the role of each component 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.


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