Fluid silencing improvements for pumps

Claim 1

AN ACOUSTIC FILTER COMPRISING: A CYLINDRICAL CASING; MEANS DEFINING A CIRCUMFERENTIAL INLET OPENING PROXIMATE ONE END OF SAID CASING; FIRST TUBULAR WALL MEANS WITHIN SAID CASING DEFINING A PASSAGE EXTENDING AXIALLY FROM THE OTHER END OF SAID CASING TOWARDS A POINT NEAR SAID ONE END; SECOND WALL MEANS WITHIN SAID CASING DEFINING AN ANNULAR PASSAGE OF GRADUALLY DECREASING RADIUS COMMUNICATING FROM SAID CIRCUMFERENTIAL OPENING TO SAID POINT; AND, AN ANNULAR CHAMBER WITHIN SAID CASING DEFINED IN PART BY SAID FIRST WALL MEANS AND POSITIONED RADIALLY EXTERIORLY OF SAID FIRST WALL MEANS, SAID ANNULAR CHAMBER COMMUNICATING WITH SAID FIRST WALL MEANS NEAR SAID POINT, SAID FIRST WALL MEANS FORMING A VENTURI SECTION WITH RESPECT TO SAID CHAMBER AT SAID POINT, WHEREBY FLUID IS DRAWN FROM SAID CHAMBER INTO SAID FIRST WALL MEANS, AND WHEREIN SAID CHAMBER FUNCTIONS TO ABSORB PULSATIONS THAT MAY CHARACTERIZE SAID FLUID.