Lawn treatment apparatus for an underground sprinkler system

Lawn treatment apparatus for delivering chemical to an underground sprinkler system comprising:

• a) a water inlet pipe having a water control valve connected to an outlet pipe for delivering water to said underground water sprinkler system, said outlet pipe having an anti-siphon valve assembly, said assembly having an anti-siphon valve housing with a threaded mouth and a threaded anti-siphon valve cap carrying an anti-siphon valve;
• b) a cylindrical, vertically extending body member having an open bottom end and an open top end mounted between said anti-siphon valve housing and said anti-siphon valve cap;
• c) means for securing said open bottom end of said body member to the threaded mouth on the anti-siphon valve housing;
• d) means disposed in said body member for mixing said chemical deposited within said body member with water flow traveling from the inlet pipe into the anti-siphon valve assembly and out through the outlet pipe to the underground sprinkler system, said mixing means comprising a vertically extending cylindrical tube located within said body member to form a space within said body member completely surrounding said tube, said tube having a top outlet port and a tapered bottom portion with an inlet port, and a control plate having a plurality of exit holes therethrough surrounding said elongated water flow tube above said tapered bottom portion, so that with said tapered portion extending into said anti-siphon valve housing, allowing water to travel from said inlet pipe into said anti-siphon valve housing, through said inlet port into and up said elongated water flow tube, out from said top outlet port through said anti-siphon valve, down through said body member around said flow tube mixing with said chemical, through said exit holes in said control plate and an exit side of the anti-siphon valve housing into said outlet pipe;
• and
• e) means for retaining said open top end of said body member to said anti-siphon valve cap, so that said anti-siphon valve prevents the water with the chemical from backing up into the water supply.