Flow control valve for intravenous fluids

Claim 1

A valve operable with means to administer fluid intravenously, comprising a. an axially extending upper non-rotary annular member forming a central passage through which fluid is flowable and having an end face with multiple grooves therein, the grooves having inner ends communicating with said passage and being generally circularly spaced, the grooves extending outwardly relative to said passage and having different cross sectional areas, and b. a rotary flow control member having an end face relatively rotatable adjacent and directly beneath said annular member end face, the control member having a flow port successively and selectively communicating with said grooves in radially outwardly spaced relation to said passage and in response to said relative rotation, said port adapted to pass fluid to administration tubing, c. a flow control chamber connected with said annular chamber to supply fluid simultaneously to said grooves via said central passage, and d. each groove having width and depth dimensions, the width dimensions being the same at all the grooves in planes normal to said axis, and the depth dimensions being different for the different grooves, and e. said grooves including an air-flush groove the depth dimension of which is at least several times greater than the largest of the depth dimensions for the remaining grooves.