1. Pulley design and material selection
The design of the pulley is the basis for ensuring its efficient and stable operation. The design of high-quality pulleys often follows strict mechanical principles, and disperses stress, reduces wear and improves durability through reasonable structural layout. For example, the rim of the pulley is usually designed to be wide and thick to enhance its load-bearing capacity and anti-deformation ability; at the same time, the shape and size of the wheel groove must be precisely matched with the transmission belt or chain to reduce sliding and wear, and ensure the efficiency and stability of power transmission.

In terms of materials, wear-resistant and corrosion-resistant materials are the first choice. Common pulley materials include cast iron, steel, aluminum alloy and some high-performance synthetic materials. Cast iron pulleys are widely used in heavy equipment due to their good wear resistance and cost-effectiveness; while aluminum alloy pulleys are more suitable for occasions where weight reduction is required due to their light weight, high strength and corrosion resistance. In addition, some new composite materials, such as carbon fiber reinforced plastics, are gradually becoming the first choice in high-end applications due to their excellent mechanical properties and corrosion resistance.

2. Manufacturing process and precision control
The quality of the manufacturing process is directly related to the final quality of the pulley. High-precision manufacturing processes can ensure that the dimensions of each component of the pulley are accurate and the surface finish is high, which is crucial to reducing friction, vibration and energy loss during operation. For example, the use of CNC machining technology can accurately control the shape and size of the pulley to ensure the perfect match between the wheel groove and the transmission belt; and surface treatment technologies such as sandblasting, polishing or plating can further improve the surface quality of the pulley, reduce wear and extend service life.

In addition, heat treatment process is also a key step to improve the performance of the pulley. Through heat treatment methods such as quenching and tempering, the microstructure of the material can be changed, its hardness and toughness can be improved, thereby enhancing the wear resistance and fatigue resistance of the pulley.

3. The influence of the use environment on the speed stability
The working environment of the lawn mower is complex and changeable, which poses a severe challenge to the speed stability of the pulley. In a humid environment, a water film is easily formed on the surface of the pulley, increasing friction resistance and even causing rust, affecting the speed and life; in a dusty environment, sand and dust particles may invade between the pulley and the transmission belt, aggravating wear and reducing transmission efficiency.

Therefore, the self-cleaning ability and sealing of the pulley need to be considered during design to reduce the negative impact of environmental factors. For example, special textures can be designed on the pulley surface to promote the discharge of water film and dust; or a sealing structure can be used to prevent external pollutants from entering the pulley.