#Hydraulic #pump is a mechanical source of power that converts mechanical power into hydraulic energy (hydrostatic energy i.e. flow, pressure). It generates flow with enough power to overcome #pressure induced by the load at the pump outlet.
There is a multiple designs for the hydraulic pump
the #gear hydraulic pump is a simple effective design and cheap
How manual #gear box works ?
The gearboxes that used in cars are used to increase torque while reducing the speed of a prime mover output shaft . This means that the output shaft of a #gearbox rotates at a slower rate than the input shaft, and this reduction in speed produces a mechanical advantage, increasing torque.