The transmission device refers to the device that transmits the motion and power of the power source to the actuator, which is located between the power source and the actuator and can change the motion speed, motion mode and force or torque. Any whole machine consists of power part, transmission device and working mechanism, and energy is transferred from power part to working mechanism through transmission device.
According to the different working media, transmission devices can be divided into four categories: mechanical transmission, electrical transmission, gas transmission and liquid transmission. The task of the overall design of the transmission device is to determine the transmission scheme, select the motor model, reasonably allocate the transmission ratio, and calculate the motion and power parameters of the transmission device, which provides the basis for the design and calculation of transmission components at all levels.
Liquid transport:
1, hydraulic transmission
It is actually a centrifugal pump-turbine system. The engine drives the centrifugal pump to rotate, and the centrifugal pump sucks the liquid from the liquid tank and drives the liquid to rotate, and finally discharges the liquid into the conduit at a certain speed. In this way, the centrifugal pump changes the mechanical energy of the engine into the kinetic energy of the liquid. The high-speed liquid discharged by the pump is sprayed on the blades of the turbine through the conduit, which makes the turbine rotate, thus becoming the mechanical energy of the turbine shaft.
2. Liquid viscous transmission
It uses viscous liquid as working medium, and relies on the viscosity of liquid between driving and driven friction plates to transmit power and adjust speed and torque. Liquid viscous transmission can be divided into two categories: one is that the oil film thickness is constant in operation, such as silicone oil fan clutch; The other is the liquid viscous transmission with variable oil film thickness, such as liquid viscous speed regulating clutch, liquid viscous brake, liquid viscous dynamometer, liquid viscous coupling and liquid viscous speed regulating device.
3. Hydraulic transmission
It is driven by the pressure energy of the liquid in the closed working volume. Hydraulic jack is a simple example of hydraulic transmission.