Flexible, oscillating blade liquid pump

A liquid conveying pump, especially a resonance pump for aquariums, which includes:

• pump housing means, holding means connected to said housing means, resiliently flexible leaf spring means secured to and supported by said holding means, alternating current operable armature means supported by said leaf spring means and spaced from said holding means in axial direction of said leaf spring means for alternate oscillation toward one side and the opposite side of said pump housing, said pump housing means having liquid inlet means and passage means including liquid outlet means, and flexible thin-walled plate means connected to said armature means axially beyond the free end of said leaf spring means while extending into said passage means for alternately swinging toward one side and the opposite side of said passage means in synchronism with the oscillation of said armature means, said plate means having a considerably lower bending resistance than said leaf spring means, the plate means being made of rubber-like material the cross section of said passage means gradually narrowing from its inner end in the direction toward said liquid outlet means, said plate means extending substantially into said narrowing part of said passage means.