Air flow rate regulation apparatus for air pump

An air flow rate regulation apparatus for regulating a volume of air discharged from an air pump used for keeping aquarium fishes, comprising:

• a cylindrical control member having a hollow chamber thereinside and a regulation hole formed in an outer peripheral surface thereof;
• and
• a cylindrical regulation member having an inner peripheral surface coming into contact with the outer peripheral surface of said control member, having a regulation recess in the inner peripheral surface thereof and made of a flexible material;
• wherein:
• said regulation member is rotatably fitted over the outer peripheral surface of said control member so as to cover said regulation hole;
• and
• said control member and said regulation member are rotated relative to each other through a rotating angle of at least 90.degree. so as to continuously increase or decrease an overlapped area of said regulation hole and said regulation recess so that a part of the air can be discharged to the atmosphere from a discharge opening disposed in said regulation recess to change the volume of air discharged from an outflow port and the final discharge volume of air can thus be regulated.

An air flow rate regulation apparatus for regulating a volume of air discharged from an air pump used for keeping aquarium fishes, comprising:

• a cylindrical control member having a hollow chamber defined thereinside and a regulation hole and a through-hole bored in an outer peripheral surface thereof, and having further a partition disposed between said regulation hole and said through-hole at the center of said hollow chamber;
• and
• a cylindrical regulation member having an inner peripheral surface coming into contact with the outer peripheral surface of said control member, having a regulation recess formed in the inner peripheral surface thereof, and made of a flexible material;
• wherein:
• said regulation member is rotatably fitted over the outer peripheral surface of said control member in such a manner as to cover said regulation hole;
• and
• said control member and said regulation member are rotated relative to each other through a rotating angle of at least 90.degree. so as to continuously increase or decrease an overlapped area of said regulation hole and said regulation recess so that the volume of air passing through said through-hole can be increased or decreased and the final discharge volume of air can thus be regulated.