Metering apparatus for a fluid infusion system with flow control station

• US 4,210,138 A
• Filed: 12/02/1977
• Issued: 07/01/1980
• Est. Priority Date: 12/02/1977
• Status: Expired due to Term

• Current Assignee: Baxter Travenol Laboratories Incorporated
• Original Assignee: Baxter Travenol Laboratories Incorporated
• Inventors: Jess, Thurman S., Zissimopoulos, Nicholas
• Primary Examiner(s): Burr, Edgar S.
• Assistant Examiner(s): Bratlie, Steven A.
• Application Number:
  US05/856,926
• Time in Patent Office: 942 Days
• Field of Search: 128/214 E, 128/214 F, 128/DIG. 12, 128/DIG. 13, 417/474-479, 417/20, 292/335, 251/7, 119/14.08
• US Class Current: 604/67
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/14232 Roller pumps
• CPC Class Codes: A61M 5/16804 Flow controllers
• CPC Class Codes: A61M 5/16854 by monitoring line pressure
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: A61M 5/365 Air detectors A61M5/1684 takes precedence; in extracorporeal blood circuits A61M1/3626
• CPC Class Codes: G05D 7/0676 by action on flow sources G05D7/0688, G05D7/0694 take precedence
• CPC Class Codes: Y10S 128/12 Pressure infusion
• CPC Class Codes: Y10S 128/13 Infusion monitoring
• CPC Class Codes: Y10T 292/558 Sliding bolt, swinging detent

Abstract

A system for infusing fluids into the human body includes a peristaltic-type metering apparatus which controls the flow of fluid through a disposable administration set. The metering apparatus includes a control system which allows the volume and rate of flow of the fluid to be infused to be accurately preset by the operator. The control system provides an alarm function in the event of malfunction of the pump or occlusion of the tubing of the administration set, and a minimum pumping rate for maintaining fluid flow through a system after the desired volume of fluid has been infused. Novel power supply circuitry within the control system renders the system immune to power line transients, and a novel bubble detector circuit provides for more reliable detection of air bubbles in the tubing. A mechanical linkage between the pressure plate and downline flow restriction plunger of the metering apparatus provides for convenient loading of the administration set and for automatic closure of the plunger prior to use.

Claims

1. Fluid metering apparatus for controlling the flow of fluid through the tubing of a fluid administration set, comprising:

a housing;

a rotor mounted on said housing for rotation about a fixed axis, said rotor including a plurality of pressure rollers disposed about the circumference thereof;

a platen assembly slidably mounted to said housing and having a pressure plate having an open position displaced from the circumference of said rotor whereby said tubing can be inserted therebetween, and having a closed position adjacent said rotor circumference whereby a segment of said tubing is positioned in compressive engagement with said pressure rollers and fluid is caused to flow along the tubing with rotation of said rotor;

flow restriction means including a plunger slidably mounted on said housing for occluding said tubing at a predetermined location downline of said tubing segment for increasing the pressure of said fluid in said tubing segment, said plunger having an open position removed from said tubing and a operating position compressively engaging said tubing;

means carried on said housing for biasing said plunger to said operating position even if said platen assembly is accidently moved to said open position; and

user-actuable latching means operable only when said platen assembly is in said open position for latching said plunger in said open position, said latching means automatically releasing said plunger to allow said plunger to move to said operating position upon actuation of said pressure plate to said closed position.

2. Fluid metering apparatus as defined in claim 1 wherein a portion of said latching means is carried on said slidably mounted platen assembly.

3. Fluid metering apparatus as defined in claim 1 wherein said latching means include a lever pivotally mounted to said platen assembly, detent means on said plunger for engaging said lever to lock said plunger for movement with said platen assembly, and actuator means on said housing for displacing said lever from said detent means upon closure of said platen assembly whereby said plunger is returned to said operating position by said biasing means.

4. Fluid metering apparatus as defined in claim 3 wherein said lever is mounted for movement in a plane generally perpendicular to said plunger, said detent means comprise a notch in said plunger dimensioned to receive said lever, and wherein means are provided for biasing said lever against said plunger whereby said lever is received in said notch when said plunger is locked in said open position.

5. Fluid metering apparatus as defined in claim 4 wherein said actuator means comprise a tapered actuator pin extending from said housing in generally parallel-spaced relationship to said plunger for displacing said lever from said notch upon closure of said platen assembly.

6. Fluid metering apparatus for controlling the flow of fluid through the tubing of a fluid administration set, comprising:

a housing;

a rotor mounted on said housing for rotation about a fixed axis, said rotor including a plurality of pressure rollers disposed about the circumference thereof;

means including a pressure plate disposed adjacent the circumference of said rotor whereby a segment of said tubing is positioned in compressive engagement with said pressure rollers and fluid is caused to flow through said tubing with rotation of said rotor;

means for rotatably driving said rotor;

flow restriction means including a slidably mounted plunger spring-biased against said tubing for occluding said tubing at a predetermined location downline of said tubing segment to increase the pressure of said fluid in said tubing segment, the position of said plunger with respect to said housing varying over a predetermined operating range with the pressure of said fluid in said tubing;

occlusion detection means including electric switch means operatively engaged with said plunger and responsive to the position thereof in said operating range for interrupting rotation of said rotor upon movement of said plunger to a predetermined position in said operating range corresponding to a predetermined partial occlusion of said tubing by said plunger.