Ball check valves

Claim 1

A CHECK VALVE COMPRISING A STRAIGHT MAIN CONDUIT WITH A BORE, AN INTEGRAL BRANCH CONDUIT MERGING AT AN ACUTE ANGLE THEREWITH AND HAVING AN OUTER END AND HAVING A BORE WHICH IS OF GREATER DIAMETER THAN SAID MAIN CONDUIT BORE TO PROVIDE GUIDING TRACKS AND TO PROVIDE AN INTEGRAL INTERNAL ANNULAR VALVE SEAT FORMED BY THE MERGER OF SAID BRANCH CONDUIT BORE WITH SAID MAIN CONDUIT BORE, WHICH SEAT IS OF LESS DIAMETER THAN THE BORE OF SAID BRANCH CONDUIT AND OF GREATER DIAMETER THAN THE BORE OF SAID MAIN CONDUIT, MEANS REMOVABLY CLOSING THE OUTER END OF SAID BRANCH CONDUIT, AND A BALL OF SUBSTANTIALLY LESS DIAMETER THAN SAID BRANCH CONDUIT BORE AND OF GREATER DIAMETER THAN SAID MAIN CONDUIT BORE SUPPORTED ON SAID TRACKS IN SAID BRANCH CONDUIT BORE FOR MOVEMENT FROM A POSITION IN ENGAGEMENT WITH SAID SEAT TO A POSITION IN SAID BRANCH CONDUIT WHERE IT NO LONGER OBSTRUCTS MOVEMENT OF LIQUID THROUGH THE MAIN CONDUIT, SAID BRANCH CONDUIT BEING OF SUCH LENGTH THAT THERE IS A BRANCH CONDUIT PORTION BEYOND THE BALL WHEN THE LATTER IS IN SAID NON-OBSTRUCTING POSITION, THERE BEING A HOLLOW WEB BETWEEN SAID BRANCH CONDUIT AND MAIN CONDUIT POSITIONED TO PROVIDE A FREE RETURN PASSAGEWAY FOR LIQUID WHICH PASSES INTO THE UPPER PORTION OF SAID BRANCH CONDUIT BEYOND SAID BALL WHEN THE LATTER IS IN SAID NON-OBSTRUCTING POSITION WITH RESPECT TO THE MAIN CONDUIT.