Liquid flow rate control device

• US 6,213,986 B1
• Filed: 11/28/1997
• Issued: 04/10/2001
• Est. Priority Date: 09/29/1995
• Status: Expired due to Fees

• Current Assignee: Buffalo Economic Renaissance Corporation
• Original Assignee: Appro Healthcare Inc.
• Inventors: Darling, Phillip H. Jr.
• Primary Examiner(s): Bockelman, Mark
• Application Number:
  US08/980,461
• Time in Patent Office: 1,229 Days
• Field of Search: 604/251-256, 604/246, 604/248, 137/423, 137/430
• US Class Current: 604/248
• CPC Class Codes: A61M 5/1411 Drip chambers A61M5/162, A61M5/1689, A61M5/40 take precedence
• CPC Class Codes: A61M 5/16818 by changing the height of the reservoir
• CPC Class Codes: A61M 5/40 using low-level float-valve to cut off media flow from reservoir position detection of a floating member A61M5/1685
• CPC Class Codes: Y10T 137/7404 Plural floats
• CPC Class Codes: Y10T 137/7426 Float co-axial with valve or port

Abstract

A fluid flow rate control device, especially adapted for controlling the flow of IV fluid to a patient, comprises a first vented fluid chamber having an upper fluid inlet end with a hollow spike which enables fluid connection with a conventional fluid container. A free floating float valve in the first chamber blocks the flow of fluid into the first chamber from the fluid container according to whether or not the fluid level in the first chamber is at a preestablished fluid level, thereby providing a constant pressure head regardless of fluid level in the fluid container. A lower end of the first chamber is connected, through a flow regulator, such as a screw-type valve, to an upper inlet end of a second, vented, drip chamber, the lower end of which is adapted for connection to a discharge tube, such as an IV tube. A second, free floating float valve in the second chamber blocks the flow of fluid from the second chamber into the discharge tube when the fluid level in the second chamber is at or below a preestablished minimum level and blocks flow of fluid into the second chamber when the fluid level in the second chamber reaches a preestablished maximum level. A first variation fluid flow control device is disclosed in which the first an second chambers are arranged in a side-by side configuration and a second variation fluid flow control device is disclosed in which fluid flow through the device is controlled in response to relative rotation between axially-aligned upper and lower shell segments of the device.

Claims

1. A gravity flow IV fluid flow device with constant fluid head provision, said device comprising:

a. an upper shell segment having an upper end region configured for receiving a flow of IV fluid from an external IV fluid source;

b. a lower shell segment having a lower end region configured for discharging said flow of IV fluid from said device, a lower region of said upper shell segment being connected to an upper region of said lower shell segment for relative rotation between the upper and lower shell segments and for limited axial movement between the upper and lower shell segments;

c. a first, upper fluid chamber defined inside said upper shell segment;

d. a second, lower fluid chamber defined in said lower shell segment, said second fluid chamber being in fluid flow communication with said first, upper chamber;

e. a fluid flow regulating valve disposed between said first and second fluid chambers, said fluid flow regulating valve being configured for varying the flow of fluid from the first chamber into the second chamber in response to relative rotation between the upper and lower shell segments, said valve including a valve seat portion disposed in said upper shell segment at the bottom of said first chamber and a valve stem disposed in an upper region of said second shell segment at the top of said second chamber, said valve seat being formed in a conical shape and said valve stem being formed in a complementary cone shape, and wherein the valve stem is responsive to relative rotation by a user between the upper and lower shell segments about the longitudinal axis of said device after assembly of said device to cause the flow rate of fluid through said valve to be varied according to the rotational position of the lower shell segment relative to the upper shell segment so as to thereby enable a user to selectively control the gravity flow of fluid from said first chamber into said second chamber without any disassembly of the device, said upper shell segment connection to said lower shell segment limiting axial movement between the upper and lower shell segments to the amount of axial adjustment of said fluid flow regulating valve;

f. a first float valve disposed in said first chamber for maintaining a preestablished fluid level in said first chamber as the fluid level in said IV fluid source decreases, and including an opening at a fluid inlet end region of the first chamber, and wherein said first float valve is constructed for floating upwardly in said first chamber and blocking said opening to stop the gravity flow of fluid through said opening from the IV fluid container when the fluid level in said first chamber rises to a preestablished fluid level.

2. The gravity flow fluid flow device as claimed in claim 1, wherein at least a side wall region of said second shell segment is constructed of a transparent material so that the inside of said second chamber is visible and the flow of IV fluid through the second chamber can be seen from outside the device.

3. The gravity flow fluid flow device as claimed in claim 1, including a first vent located at an upper region of said first chamber above said preestablished fluid level for venting the first chamber to ambient pressure, and a second vent located at an upper region of said second chamber for venting the second chamber to ambient surrounding pressure.

4. The gravity flow fluid flow device as claimed in claim 1, including an index mark on one of the upper and lower shell segments and including a calibrated scale on the other one of the upper and lower shell segments, said scale being calibrated to indicate the rate of fluid flow from the first chamber into the second chamber.

5. A gravity flow IV fluid flow device with constant fluid head provision, said device comprising:

a. an upper shell segment having an upper end region configured for receiving a flow of IV fluid from an external IV fluid source;

b. a lower shell segment having a lower end region configured for discharging said flow of IV fluid from said device, a lower region of said upper shell segment being connected to an upper region of said lower shell segment for relative rotation between the upper and lower shell segments and for limited axial movement between the upper and lower shell segments;

c. a first, upper fluid chamber defined inside said upper shell segment;

d. a second, lower fluid chamber defined in said lower shell segment, said second fluid chamber being in fluid flow communication with said first, upper chamber;

e. a fluid flow regulating valve disposed between said first and second fluid chambers, said fluid flow regulating valve being configured for varying the flow of fluid from the first chamber into the second chamber in response to relative rotation between the upper and lower shell segments, said valve including a valve seat portion disposed in said upper shell segment at the bottom of said first chamber and a valve stem disposed in an upper region of said second shell segment at the top of said second chamber, said valve seat being formed in a conical shape and said valve stem being formed in a complementary cone shape, and wherein the valve stem is responsive to relative rotation by a user between the upper and lower shell segments about the longitudinal axis of said device after assembly of said device to cause the flow rate of fluid through said valve to be varied according to the rotational position of the lower shell segment relative to the upper shell segment so as to thereby enable a user to selectively control the gravity flow of fluid from said first chamber into said second chamber without any disassembly of the device, said upper shell segment connection to said lower shell segment limiting axial movement between the upper and lower shell segments to the amount of axial adjustment of said fluid flow regulating valve;

f. a first float valve disposed in said first chamber for maintaining a preestablished fluid level in said first chamber as the fluid level in said IV fluid source decreases, and including an opening at a fluid inlet end region of the first chamber, and wherein said first float valve is constructed for floating upwardly in said first chamber and blocking said opening to stop the gravity flow of fluid through said opening from the IV fluid container when the fluid level in said first chamber rises to a preestablished fluid level; and

g. a second float valve disposed in said second chamber for maintaining a preestablished fluid level in said second chamber, and including an outlet opening at a fluid outlet end region of the second chamber, and wherein said second float valve is constructed for floating downwardly in said second chamber and blocking said outlet block said outlet opening when the fluid level in said second chamber falls to a preestablished fluid level.