Rotary piston type water meter measuring chamber structure

The utility model discloses a rotary piston type water meter measuring chamber structure, which comprises an outer casing, a piston and an end cap. The outer casing is equipped with a water inlet, an upper cylinder is arranged at the center of a piston chamber, a rotary sleeve sleeved on a mandrel of a measuring chamber is arranged at the center of the upper cylinder, a vertical partition board is inserted beside the water inlet, the outer circle of the piston is axially provided with an opening, the middle of the piston is provided with an integrated transverse partition board which is distributed with water inlet orifices, a shifting rod is tightly engaged with the upper portion of a piston mandrel, the end cap is provided with a water outlet and a lower cylinder, a shifting block connected with the shifting rod is arranged at the center of the lower cylinder, and a shifting fork shifting a counting mechanism is arranged on the shifting block. The piston generates rotating torsion to perform eccentric rotat