Typical structure of crankshaft connecting rod radial piston motor

Typical structure of crankshaft connecting rod radial piston motor

a. The single acting crankshaft connecting rod type quantitative radial piston motor is shown in Fig. y. the motor adopts shaft flow distribution. The star shaped housing 4 of the motor has a cylindrical hole arranged radially, and the hole end is closed by the cylinder head 7. The plunger 6 acts on the crankshaft (integrated with the eccentric) 3 through the connecting rod 5. The crankshaft is mounted on the rolling bearings 2 and 10 and drives the valve distribution shaft 12 to rotate through the cross coupling 8. The port shaft is installed in the current collector 9 and supported by the needle roller bearing 11. The ball joint of connecting rod 5 and the bearing surface of connecting rod in contact with crankshaft are in the form of hydrostatic bearing, and the pressure oil enters into the hydrostatic bearing through the small hole of piston cylinder. This structure can reduce the friction loss of the most important parts. When the high-pressure oil enters the piston cylinder of the motor through the current collector 9 and the valve distribution shaft, the piston acts on the crankshaft through the connecting rod and makes it rotate, thus driving the working mechanism connected with the motor. There are two kinds of motors, single row and double row. Each row has five or seven plungers.

b. The structure of single acting crankshaft connecting rod variable radial piston motor is shown in Figure Z. By changing the eccentricity to make the motor variable. A small piston 2 and a large piston 3 are installed on the crankshaft. When the small piston cavity is filled with control oil and the large piston cavity is filled with return oil, the small piston moves upward under the action of pressure oil and pushes the eccentric ring 1 to the maximum eccentric position. At this time, the motor displacement and output torque are the maximum and the speed is the minimum. If the position of the motor is changed by the directional valve, the control oil is injected into the large piston cavity and the return oil is injected into the small piston cavity, the large piston moves downward under the action of the pressure oil, and the eccentric ring is pushed to the minimum eccentric position. At this time, the motor has a small displacement. Under the same oil supply, the output speed increases and the output torque decreases correspondingly. The change of eccentricity can be carried out smoothly in the motor operation; the pressure oil of the motor itself can be used as the control oil, which saves the control oil source; the motor can be combined with the quantitative pump to form a volume speed regulation circuit, which can effectively realize constant power speed regulation. It is especially suitable for towing winch or driving vehicle wheels.

Figure a shows the structure of single acting crankshaft connecting rod variable radial piston motor with slide valve distribution. Each plunger of the motor is equipped with a separate valve spool 1, which is moved by the auxiliary eccentric cam 2. A displacement adjusting mechanism is composed of a speed regulating cylinder 3, a pull rod 4 and a push rod 5. When the piston of the speed regulating cylinder moves, it drives the pull rod to slide left or right to push the push rod down or up. By changing the position of eccentric ring 6, the eccentricity can be changed and the displacement can be adjusted.