Pressure regulator for infusor

• US 6,892,755 B2
• Filed: 02/28/2003
• Issued: 05/17/2005
• Est. Priority Date: 02/28/2003
• Status: Expired due to Fees

• Current Assignee: Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Black, Larry
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US10/376,409
• Publication Number:
  US 20040168723A1
• Time in Patent Office: 809 Days
• Field of Search: 137/505.39, 137/505.41, 137/505.42, 137/505.43, 604/118, 604/132
• US Class Current: 137/505.41
• CPC Class Codes: A61M 2205/3331 Pressure; Flow
• CPC Class Codes: A61M 5/152 pressurised by contraction of elastic reservoirs containers for dispensing contents by contraction of an elastic bag provided therein, in general B65D83/0061
• CPC Class Codes: A61M 5/16877 Adjusting flow; Devices for setting a flow rate
• CPC Class Codes: G05D 16/0655 using one spring-loaded membrane
• CPC Class Codes: Y10T 137/7819 Rectilinear valve stem rigid with reactor surface
• CPC Class Codes: Y10T 137/7825 Rectilinear valve stem rigid with reactor surface

Abstract

An improved ambulatory infusion device for dispensing a fluid into a patient includes a flexible bladder enclosure having a first open end a closed second end. The closed second end of the sheath is free to conform to the body of the patient so that the device is comfortable when worn. In other aspects, a pressure regulator of the device is adapted to maintain the outlet pressure within a predetermined range of pressures so that the fluid flow rate is substantially constant during fluid flow. A flow restrictor of the device is formed of flexible tubing.

An ambulatory infusion device for dispensing a fluid at a predetermined fluid flow rate includes an elastic bladder having an interior volume for storing the fluid under pressure and an opening for dispensing the fluid. A pressure regulator is in fluid communication with the opening of the bladder and includes an inlet for receiving fluid from the bladder at an inlet pressure and an outlet for discharging the fluid at a predetermined outlet pressure. A valve at the inlet has a hemispheric-shaped head adapted to cooperate with a frustoconic-shaped seat to promote uniform fluid flow therebetween. A movable diaphragm is connected to the valve, and a valve plate opposite a surface of the diaphragm has channels or texture therein. The diaphragm and the valve are movable in response to the fluid pressure acting on the diaphragm surface.

Claims

1. An ambulatory infusion device for dispensing a fluid at a predetermined fluid flow rate, comprising:

an elastic bladder having an interior volume for storing the fluid under pressure and an opening for dispensing the fluid;

a pressure regulator in fluid communication with the opening of the bladder, the pressure regulator including an inlet for receiving fluid from the bladder at an inlet pressure, an outlet for discharging the fluid at a predetermined outlet pressure, a valve at the inlet having a hemispheric-shaped head adapted to cooperate with a frustoconic-shaped seat to promote uniform fluid flow therebetween, a movable diaphragm connected to the valve, and a valve plate opposite the diaphragm having channels or texturing therein for receiving fluid flowing through the valve, the diaphragm and the valve being movable in response to fluid pressure to maintain the outlet pressure within a predetermined range of pressures so that the fluid flow rate is substantially constant during fluid flow.

2. An infusion device as set forth in claim 1 wherein the diaphragm includes a fluid flow ring having a hole therethrough for directing fluid to an outlet of the pressure regulator, a channel of the valve plate being in fluid communication with the hole of the fluid flow ring.

3. An infusion device as set forth in claim 2 wherein the fluid flow rate remains substantially constant when the inlet pressure is up to about 5 times greater than the outlet pressure.

4. An infusion device as set forth in claim 1 further comprising a flow restrictor in fluid communication with the pressure regulator and positioned downstream therefrom, wherein the flow restrictor is tubing having an inside diameter sized about 0.0022 inches.

5. An infusion device as set forth in claim 4 wherein the pressure regulator is connected to the flow restrictor by intermediate tubing.

6. An infusion device as set forth in claim 5 wherein the outlet pressure of the pressure regulator is substantially equal to the inlet pressure of the flow restrictor.

7. An infusion device as set forth in claim 1 wherein pressure is exerted on the fluid in the bladder due to the elasticity of the bladder.

8. An infusion device as set forth in claim 1 wherein the valve includes a valve stem extending from the head through the movable diaphragm and a diaphragm backing plate, the stem terminating at an opposite end of the valve from the head, the opposite end being supported by the backing plate such that movement of the backing plate away from the valve plate is fully transmitted directly to the valve and to allow the valve stem and head to pivot for centering of the head relative to the seat during fluid flow.

9. An infusion device as set forth in claim 8 wherein the opposite end of the stem engages the diaphragm such that the stem and head may pivot relative to the diaphragm.

10. An infusion device as set forth in claim 1 wherein the pressure regulator constitutes a closed-loop flow controlling system.

11. An ambulatory infusion device for dispensing a fluid at a predetermined fluid flow rate, comprising:

an elastic bladder having an interior volume for storing the fluid under pressure and an opening for dispensing the fluid;

a pressure regulator in fluid communication with the opening of the bladder, the pressure regulator including an inlet for receiving fluid from the bladder at an inlet pressure, an outlet for discharging the fluid at an outlet pressure, a valve plate, and a valve at the inlet including a hemispheric-shaped head at one end adapted to cooperate with a frustoconic-shaped seat of the valve plate and a valve stem extending from the head through a movable diaphragm and through a diaphragm backing plate, the valve stem terminating at an opposite end of the valve from the head, the opposite end being supported by the backing plate such that movement of the backing plate away from the valve plate is substantially transmitted directly to the valve and to allow the valve stem and head to pivot for centering of the head relative to the seat during fluid flow.