Variable nozzle

Claim 1

A CONTROL SYSTEM FOR JET-PROPELLED WATERCRAFT COMPRISING A CONDUIT MOUNTED ON THE CRAFT AND EXTENDING AND OPENING REARWARDLY THEREOF, SAID CONDUIT HAVING AN INTERIOR HOLLOW THERETHROUGH WHICH IS CIRCULAR IN CROSS SECTION AND CONVERGES TO THE REARWARD OPENING THEREOF, A FLEXIBLE ANNULAR ELEMENT SECURED TO SAID CONDUIT WITHIN THE REARWARD OPENING THEREOF, MEANS FOR INFLATING SAID FLEXIBLE ANNULAR ELEMENT FOR REDUCING THE SIZE OF SAID REARWARD OPENING, A PUMP IN SAID CONDUIT, A PLURALITY OF STATOR VANES FIXED TO THE CONDUIT AND EXTENDING INWARDLY IN SAID PASSAGE BETWEEN SAID PUMP AND SAID OPENING, A RING FIXED TO THE INNER ENDS OF SAID VANES AND POSITIONED COAXIALLY OF SAID PASSAGE, A CONTROL ELEMENT SLIDABLY MOUNTED IN SAID RING, SAID CONTROL ELEMENT ENGAGING SAID RING AND HAVING AN OUTER PERIPHERY WHICH TAPERS FROM THE OUTER PERIPHERY OF SAID RING TO A MAXIMUM DIAMETER AND CONVERGES FROM SAID MAXIMUM DIAMETER IN A FRUSTO-CONICAL SHAPE, SAID MAXIMUM DIAMETER BEING LARGER THAN SAID OPENING, AND MEANS FOR PROJECTING SAID CONTROL ELEMENT TOWARD SAID OPENING TO VARY THE SIZE OF THE PASSAGE BETWEEN SAID CONDUIT AND THE CONTROL ELEMENT FROM A RELATIVELY LARGE ANNULAR SHAPE THROUGH INTERMEDIATE SIZED ANNULAR SHAPES TO A COMPLETE CLOSURE.