INFLATING AND DEFLATING DEVICE FOR BALLOON DILATATION CATHETERS

摘要

of the Invention Inflating and deflating device for a balloon dilatation catheter comprising a housing and a syringe carried by the housing. The syringe has an outlet adapted to be connected to the catheter. The syringe includes a container and a piston which is slidably mounted in the container. The syringe also includes a rigid plunger connected to the piston and extends out of the housing. The plunger has helical threads formed thereon to provide an elongate ratchet. A pawl is movable between rachet-engaging and rachet-disengaging positions. A spring is carried by the housing and engages the pawl and yieldably urges the pawl into its rachet-engaging position. A tab is carried by the housing and engages the pawl and is used for moving the pawl out of engagement with the ratchet to release the ratchet. The pawl and the ratchet are formed so that when the syringe contains a liquid, the plunger can be pushed inwardly by hand to provide a desired pressure on the liquid in the container and the plunger can be rotated to gradually increase or decrease the pressure on the liquid in the container. A 42608/ld