Hydraulic motor Structure of:

1、 Vane type

Based on the action of pressure oil, the unbalanced pressure makes the rotor appear torque. The output torque of the vane type hydraulic motor is related to the displacement of the hydraulic motor and the pressure difference between the inlet and outlet of the hydraulic motor, and its speed is determined by the flow of the input hydraulic motor. Since the hydraulic motor is usually specified to be capable of forward and reverse rotation, the blades of the vane type hydraulic motor should be placed radially. In order to ensure that there is pressure oil at the blade root all the time, a one-way valve should be set on the path between the return and pressure oil cavities and the blade root. In order to ensure the normal operation of the vane hydraulic motor after the pressure oil is connected, the top of the blade must be in close contact with the inner surface of the stator to ensure excellent sealing. Therefore, a preloaded torsion spring should be set at the blade root. The vane type hydraulic motor has small volume, small moment of inertia, flexible operation, and can be used in places with high reversing frequency; However, the leakage is large and unstable during slow operation. Therefore, the vane type hydraulic motor is usually used in places with high speed, small torque and flexible operation regulations.

2、 Radial plunger type

Radial plunger hydraulic motor In principle, when the pressure oil enters the bottom end of the plunger in the cylinder through the window of the fixed oil distribution shaft 4, the plunger extends outward, firmly against the inside of the stator, based on the eccentricity between the stator and the cylinder. At the contact between the plunger and the stator, the reaction force between the stator and the plunger is. The force can be divided into two components: and. When the oil pressure acting on the bottom end of the plunger is p, the diameter of the plunger is d, and the included angle between the force and the middle is X, the force will produce a torque on the cylinder block to stabilize the cylinder block. The cylinder body then outputs torque and speed outward by virtue of the transmission shaft connected to the end face. The torque state of the two plungers described above is based on the fact that there are many plungers in the oil pressure area. The torque on such plungers can stabilize the cylinder block and output torque. Radial plunger hydraulic motor It is mostly used in the state of slow speed and large torque.

1. Single acting connecting rod type radial piston motor

The connecting rod motor diagram, shaft flow distribution hydraulic motor diagram and five corner radial motor assembly animation show the operation structure diagram of the single acting connecting rod radial piston motor, which is in a five corner shape. The motor is composed of housing 1, crankshaft 6, port shaft 5, connecting rod 3, plunger 2, eccentric wheel 4 and other parts. Advantages: simple structure and accurate operation. Disadvantages: large volume, heavy weight, pulsation of rotation and torsion, slightly poor stability at slow speed.

2. Multi action Internal curve plunger motor

The motor is composed of port shaft 1, cylinder block 2, plunger 3, cross beam 4, roller 5, stator 6, output shaft 7, etc. The displacement of this type of motor is twice that of single stroke motor. There are 21 plungers. Based on the increase of equivalent plunger number, under the same load, the corresponding increase of output torque will reduce the torque pulsation rate. Sometimes this type of motor is made of multi row plunger, the number of plunger is increasing, the output torque is further increased, and the torque pulsation rate is further reduced. Therefore, this kind of motor can be made into a very large displacement, and can be stable at very low speed. Since the motor must be stable in both directions, the blade slots are arranged radially.

3. Plunger type High speed hydraulic motor

The plunger type high-speed hydraulic motor is usually axial type.

3、 Axial plunger motor

Except for valve type flow distribution, other types of axial piston pump can be used as hydraulic motor under normal conditions, that is, axial piston pump and axial piston motor are reversible. The principle of the axial piston motor is that the oil distribution plate and swashplate are fixed, and the motor shaft and the cylinder block are connected and rotate together. When the pressure oil enters into the plunger hole of the cylinder block through the window of the oil distribution plate, the plunger extends under the action of the pressure oil and is close to the swashplate. The swashplate has a normal reaction force p against the plunger, which can be divided into the axial component force and the vertical component force Q. Q is in balance with the hydraulic pressure on the plunger, and Q makes the plunger have a turning distance to the center of the cylinder block, pushing the motor shaft to rotate counterclockwise. The instantaneous total torque of the axial piston motor is pulsating. If the motor pressure oil input direction is changed, the motor shaft rotates clockwise. The change of swashplate angle a, that is, the change of displacement, not only interferes with the torque of the motor, but also interferes with its rotation speed and steering. The greater the tilt angle of the swashplate, the greater the torque and the lower the rotation speed.

4、 Gear motor

In order to better meet the requirements of forward and reverse rotation, the gear motor structure type has the same oil outlet and inlet, symmetrical and independent oil leakage ports, which lead the leakage oil at the bearing out of the housing; In order to better reduce the running friction torque, rolling bearings are adopted; To better reduce torque pulsation, Gear hydraulic motor The gear module of is more than that of the pump. The gear hydraulic motor has poor dry sealing performance, low volumetric efficiency, high input oil pressure and relatively large torque. And the instantaneous rotation speed and torque change with the change of the meshing point, so the gear hydraulic motor is only suitable for the places with high speed and small torque. It is usually used for construction machinery, agricultural machinery and equipment with low demand for torque balance.

5、 High speed motor

The motor with rated rotation speed exceeding 500r/min belongs to high-speed motor. The basic types of high-speed motors are gear type, vane type and axial plunger type. They are characterized by high rotation speed, small moment of inertia, convenient operation, braking, speed change and reversing.

VI Low speed motor

Hydraulic motor with rotation speed less than 500r/min belongs to Low speed hydraulic motor 。 Its basic type is radial plunger type. The main characteristics of the low-speed hydraulic motor are: large displacement, large volume, low rotation speed, direct connection with the operating mechanism, no speed reduction system, which greatly simplifies the transmission mechanism. The output torque of the low-speed hydraulic motor is relatively large, which can reach thousands to tens of thousands of Nm, so it is also called Low speed high torque hydraulic motor 。