Device for the intravenous or enteric infusion of liquids into the human

Abstract

A portable device for accurately metering a liquid for intravenous or enteric infusion into a patient's body in which the pressure from a pressure source is utilized to pressurize the liquid and the pressurized liquid becomes the sole driving force to meter and to infuse the liquid into the body. The pressurized liquid is applied alternately to one of a pair of flexible liquid bladders the other one being connected to a discharge device such as a tube so that, as one liquid bladder is filled with pressurized liquid, the other bladder is emptied into the patient. The expanding liquid bladder and the contracting liquid bladder cooperate with a teeter totter type control which applies pressure to the contracting liquid bladder and is damped to control the rate of expansion and contraction. The position of the teeter totter controls the valving for applying pressurized fluid from one side to the opposite by alternatively selecting channels of fluid flow to each liquid bladder. The angular motion of the teeter totter is controlled by a pair of flexible damping bladders connected through an adjustable constant flow valve which is disposed on the side of the teeter totter opposite the liquid bladders.