Pin-Gear Drive is a special form of fixed axle gear transmission. The large wheel with cylindrical pin teeth is called pin wheel. It can be divided into outer gearing pin gear transmission (see Figure 3-7 ①), inner gearing pin gear transmission (see Figure 3-7 ②) and the rack gearing pin gear transmission (see Figure 3-7 ③). As the pin wheel is round pin shaped, it has simple structure, easy processing, low cost, easy overhaul compared to the general gear. Suitable for low-speed and heavy-duty mechanical transmission and for occasions with more dust, poor lubrication condition and so on.​​​​​​​