| 主权项 |
1. A backflow prevention device, the backflow prevention device comprising:
a housing defining a water flow stream; an upstream shutoff valve, wherein the upstream shutoff valve is configured to allow a user to control water flow through the housing; a check valve:
located within the housing downstream of the upstream shutoff valve; andincluding:
an orifice, wherein the orifice is configured for the flow of water through the check valve; anda clapper, wherein the clapper is configured to:
allow water flow, in the downstream direction, through the orifice; andprevent water flow, in the upstream direction, through the orifice; a downstream shutoff valve, wherein the downstream shutoff valve is:
located downstream of the check valve; andconfigured to allow a user to control the water flow stream through the housing; wherein at least on one of the shutoff valves includes an obstruction, wherein the obstruction is configured to:
prevent water flow at a first position;allow water flow at a second position; androtate from first position to second position about an axis of rotation, wherein the axis of rotation is:
substantially parallel to the direction of the water flow stream as the water flow stream passes the obstruction; andpositioned such that the water flow stream passes the obstruction at openings spaced about the axis when in the second position. |
