What is the name of the fixed pulley fixed on the flagpole shaft?

The immovable pulley on the flagpole is called the crown block. Like the pulley at the top of the flagpole, the pulley that rotates in a fixed position is called the crown block. The crown block is fixed at a certain point on the flagpole. The rope has to bypass the crown block to pull up the ground object, and the pulling force is equal to the gravity of the object, and the direction is opposite. Different from the moving pulley, the moving pulley rises with the suspended object, but the tension is half of gravity, and the direction is opposite, which is labor-saving and labor-saving. The crown block and the moving pulley can form a pulley block.

Characteristics of crown block:

1, when pulley is used, the pulley with fixed shaft position is called crown block. The crown block is not labor-saving, such as F=G, but it can change the direction of force. It belongs to the application of pulley principle and the discussion of mechanical work. Essentially, the power arm is equal to the lever of the resistance arm.

2. When using the crown block, the pulling distance is equal to the rising distance of the object, which is neither labor-saving nor laborious. The tension at both ends of the rope is equal, so when the output force is equal to the input force, the mechanical efficiency of the crown block is close to 1 regardless of friction.