Abstract: An infusion device includes a pump forming front and rear chambers for receiving medicaments therein. The medicaments supplied from the two chambers are respectively transmitted into an elastic reservoir forming first and second lumens through first and second passageways. Then, the medicaments are infused into a person through a catheter which defines one passageway toward the human body. The first passageway is in fluid communication with the front chamber and second lumen. The second passageway is in fluid communication with the rear chamber, the first lumen, and the second lumen. By making the diameter of a second hole which connects the first lumen and second lumen smaller than a first hole which connects the first passageway and the first lumen, the medicament from the second chamber can be infused into patient with a low concentration.

Abstract: An infusion device includes a pump forming front and rear chambers for receiving medicaments therein. The medicaments supplied from the two chambers are respectively transmitted into an elastic reservoir forming first and second lumens through first and second passageways. Then, the medicaments are infused into a person through a catheter which defines one passageway toward the human body. The first passageway is in fluid communication with the front chamber and second lumen. The second passageway is in fluid communication with the rear chamber, the first lumen, and the second lumen. By making the diameter of a second hole which connects the first lumen and second lumen smaller than a first hole which connects the first passageway and the first lumen, the medicament from the second chamber can be infused into patient with a low concentration.

Abstract: An infusion device comprises a pump having first and second chambers that are sealed by a penetrable membrane; an injection catheter comprises a first passageway which is connected to the first chamber; and an expandable elastic pouch which is mounted to the injection catheter and is connected to the second chamber through inlet holes defined in a wall of the second passageway. The expandable elastic pouch further connects an outlet port of the injection catheter through some outlet holes which are also defined in the wall. Medicaments are filled into the chambers and can either be directly injected through to the first passageway, or transmitted to the elastic pouch. The elastic pouch is expanded, and accordingly, a pressure is induced on the medicament to effectively continuous deliver the medicament for a given period of time.