Medical liquid infusion apparatus

• US 7,867,198 B2
• Filed: 08/05/2005
• Issued: 01/11/2011
• Est. Priority Date: 08/16/2004
• Status: Expired due to Fees

• Current Assignee: Daiken IkI Kabushiki Kaisha
• Original Assignee: Daiken IkI Kabushiki Kaisha
• Inventors: Kobayashi, Takeharu, Ihara, Hiroshi, Yamada, Keiichi, Yoshida, Makoto
• Primary Examiner(s): KOHARSKI, CHRISTOPHER
• Application Number:
  US11/660,257
• Publication Number:
  US 20090137955A1
• Time in Patent Office: 1,985 Days
• Field of Search: 604140-144, 604146-147, 604/70, 604/890.1, 604/891.1, 604 65- 68
• US Class Current: 604/141
• CPC Class Codes: A61M 2005/14264 with means for compensating influence from the environment
• CPC Class Codes: A61M 2005/14268 with a reusable and a disposable component
• CPC Class Codes: A61M 2205/8225 using incorporated gas cartridges for the driving gas
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14526 the piston being actuated by fluid pressure

Abstract

An object is to provide a medical liquid infusion apparatus suitable for a portable use and capable of suppressing an abrupt change in flow rate even when the environmental temperature rises. A medical liquid infusion apparatus 1 is provided with a driving portion 2 and configured to infuse a medical liquid inside a medical liquid container 3 to a patient by applying a pressure to the medical liquid container 3 using a driving force of the driving portion. The driving portion 2 includes a compressed gas cylinder 4 filled with a compressed gas, and it is configured in such a manner that the driving force is generated by the pressure inside the compressed gas cylinder 4.

Claims

1. A medical liquid infusion apparatus provided with a driving portion and configured to infuse a medical liquid inside a medical liquid container into a patient by applying a pressure to the medical liquid container using a driving force of the driving portion, wherein:

the driving portion includes a compressed gas cylinder filled with a compressed gas alone, and the driving force is generated by a pressure inside the compressed gas cylinder, the compressed gas cylinder including an on-off valve configured to close the compressed gas cylinder using a pressure of the compressed gas, when no external force is conferred thereto,

wherein the driving portion further includes;

a main body portion allowed to communicate with an interior of the compressed gas cylinder by opening the on-off valve;

a diaphragm valve that defines a compression chamber capable of sealing the compressed gas flown from the compressed gas cylinder in a space between the main body portion and the medical liquid container;

a pushing member that pushes the diaphragm valve toward the compression chamber from an outside open to atmosphere; and

a link member that allows the on-off valve and the diaphragm valve to operate in synchronization with each other in such a manner that a first resultant force obtained by adding a force to close the on-off valve and a force to expand the diaphragm valve outward using the pressure inside the compression chamber is balanced out with a second resultant force to push the diaphragm valve toward the compression chamber using an atmospheric pressure and a pushing force of the pushing member, and

wherein the pressure inside the compression chamber is used as the driving force.

2. The medical liquid infusion apparatus according to claim 1, wherein:

the driving portion is configured so as to be attachable to and detachable from the medical liquid container.

3. The medical liquid infusion apparatus according to claim 1, wherein:

the medical liquid container has been previously filled with a specific medical liquid.

4. The medical liquid infusion apparatus according claim 1, wherein:

the medical liquid container has a hole formed to have a minimal sectional area, and a flow rate adjustment member capable of adjusting a flow rate of the medical liquid by forcing the medical liquid discharged according to the driving force to pass through the hole so as to produce a pressure loss.

5. The medical liquid infusion apparatus according claim 1, wherein:

the medical liquid container includes a cylinder to hold the medical liquid and a piston that slides within the cylinder along an axial direction thereof to allow the medical liquid to be discharged from a tip end side of the cylinder; and

an interior of the cylinder is formed in a tapered-shape that narrows toward the tip end side.

6. The medical liquid infusion apparatus according claim 1, wherein:

the diaphragm valve is made of a material having high gas permeability at least in part.