DUST COLLECTION METER FOR VACUUM CLEANER

PURPOSE:To prevent the suction force of a vacuum cleaner body from lowering without the ambient air flowing into the vacuum cleaner body by fixing one end part of a diaphragm to the opening side of a pipe in an air-tight manner. CONSTITUTION:A bottomed cylindrical part 14 is slidably disposed in a pipe 7, and is urged by a diaphragm 15 toward to the suction port 8 side of the pipe 7 so as to close the suction port 8 of the pipe 7. The resilient diaphragm 15 is expandable disposed in the pipe 7, one end part thereof being fixed to a support part 14 so as to urge the support part 14 toward the suction port 8 of the pipe 7 and the other end part thereof being fixed to the opening 9 side of the pipe 7 in an air-tight manner so as to prevent air from flowing into the vacuum cleaner body from the suction port 8. When the volume of air passing through a dust collecting chamber is reduced due to build-up of dust in the dust collecting chamber so that the pressure of a storage chamber in which a motor driven blower is disposed becomes negative, the support part 14 in a dust collection meter is pressed by the ambient air, and accordingly, it slides so as to indicate the build-up of dust. At this time, the ambient air flows into the pipe 7 from the suction port 8, but is prevented from flowing into the vacuum cleaner body since the end part of the diaphragm 15 is fixed to the opening 9 side of the pipe 7 in the air-tight manner.