Heater for shrink fit chucks and blocking unit of the heater

A heater for shrink fit chucks comprising:

• a heat gun assembly having a heat gun having an air outlet for discharging hot air;
• a heating cover connected to the heat gun and having
• a first through hole;
• a second through hole;
• and
• a heating space disposed within the heating cover, extending along an extending direction to form the first through hole and the second through hole, and communicating with the air outlet of the heat gun;
• a blocking piece having
• a blocking body detachably connected to the heating cover to block the first through hole;
• and
• a communicating hole formed through the blocking body and capable of communicating with the first through hole;
• an adjustable blocking set connected to the heating cover and having
• a housing;
• and
• two blade assemblies mounted inside the housing and capable of blocking the second through hole and having
• multiple blades disposed annularly along the extending direction;
• and
• a switching component mounted inside the housing, rotatably disposed between the two blade assemblies, capable of pushing the multiple blades of each one of the two blade assemblies to move toward or depart from each other, and having a manual protrusion extending out of the housing.