WATER PURIFIER

PROBLEM TO BE SOLVED: To provide a water purifier making sure a zero resetting of a display part at an exchange time of filter medium by a simple mechanical structure, in a mechanism for displaying a measure of exchange of the filter medium in the water purifier. SOLUTION: An impeller rotatable with a water stream is arranged in a water path of a filter part, and a constitution in which plural gears being a transmission mechanism for reducing and transmitting the rotation of the impeller, and a display part 7 for displaying a water purifying cartridge 2 in the final stage of the gears, housed in a slide part 4 moving to coincide with detachment of the water purifying cartridge 2, are provided, is housed in a casing 8, and the purifier is constituted such that the zero resetting is performed such that the display part 7 is off from the gears by the exchange of the water purifying cartridge 2. Respective gears are vertical with respect to the moving direction of the water purifying cartridge 2, thus error, or the like. The attachment of the water purifying cartridge 2 can be absorbed, thus the water purifier by which the display part 7 is surely connected with the gears, is obtained.