Particle sensing device and air conditioner including the same

A particle sensing device comprising:

• a sensor including a sensing path through which air passes;
• a flow path housing which accommodates the sensor and guides air;
• and
• a blower unit which causes external air to pass through the sensing path and be discharged to the outside,
• wherein the flow path housing includes:
• a suction port through which air is suctioned;
• a suction path which vertically extends and guides air suctioned from the outside;
• a guide path which extends obliquely upward from the suction path and guides air to the sensing path;
• a particle discharge port provided at a lower side of the suction path and configured to discharge particles;
• and
• an air discharge port through which air having passed through the sensing path is discharged.

A particle sensing device comprising:

• a sensor including a sensing path through which air passes;
• a first suction path which guides air including fine particles into the sensing path in a first direction;
• and
• a second suction path which guides air including ultrafine particles into the sensing path in a second direction different from the first direction,
• wherein the sensor is rotatably installed and is selectively connected to one of the first suction path and the second suction path according to a rotation angle of the sensor.