Abstract: A blow-off valve for a turbo blower 1000 has a body part 100 which includes a cylinder part 110, a valve-guide plate 130 on the cylinder part 110 and a head part 150 covering the valve-guide plate 130. In the cylinder part 110, a blow-connection opening 1038 connected with a blow opening 2500 of the turbo blower 2000 and a blow-off opening 1058 to blow off the emission air from the turbo blower 2000. A spool valve 300 is provided and a blow-pressure spool 380 is located at space connected with the blow-connection opening 1038 and a blow-pressure opposing spool 330 is located between the valve-guide plate 130 and the head part 150 and a stem of the spool valve penetrates the valve-guide plate 130 and is supported thereby. A three-way solenoid valve 20 is mounted on the head part 150.

Abstract: A blow-off valve for a turbo blower 1000 has a body part 100 which includes a cylinder part 110, a valve-guide plate 130 on the cylinder part 110 and a head part 150 covering the valve-guide plate 130. In the cylinder part 110, a blow-connection opening 1038 connected with a blow opening 2500 of the turbo blower 2000 and a blow-off opening 1058 to blow off the emission air from the turbo blower 2000. A spool valve 300 is provided and a blow-pressure spool 380 is located at space connected with the blow-connection opening 1038 and a blow-pressure opposing spool 330 is located between the valve-guide plate 130 and the head part 150 and a stem of the spool valve penetrates the valve-guide plate 130 and is supported thereby. A three-way solenoid valve 20 is mounted on the head part 150.