| 摘要 |
A small orifice in a flush valve piston is provided with a filter means to prevent sedimentary deposits from clogging the orifice. The filter is formed by providing a generally three-sided channel around the piston. The channel is located such that the orifice opens into the base of the channel. A resilient sealing ring is seated on the channel to close the open side of the channel. A plurality of grooves extend from the interior of the channel, under the sealing ring and to the exterior of the piston. These grooves are sized to prevent entry of sedimentary deposits into the channel while permitting entry of water in the channel. The grooves are individually small compared to the orifice opening but they are sufficient in number to provide an adequate supply of water to the orifice. |
