Air in-line sensor for ambulatory drug infusion pump

Abstract

An air in-line sensor 10 for detecting air bubbles in a therapeutic solution flowing through a tube 12 utilizes a unitary type sensor having a channel 16 for receiving the tube 12. The channel 16 has a tube loading section 18. A signal emitting member 20 is positioned on one side of the tube 12 and a signal receiving member 22 is positioned on an opposite side of the tube 12. A first air baffle 24 is positioned between the signal emitting 20 and signal receiving members 22.

We claim:  
     
         1 . An air in-line sensor for detecting air bubbles in a therapeutic solution flowing through a tube, the sensor comprising: 
 a channel for receiving the tube having a tube loading section;    a signal emitting member positioned on one side of the tube and a signal receiving member positioned on an opposite side of the tube; and,    a first air baffle positioned between the signal emitting member and the signal receiving member.    
     
     
         2 . The sensor of  claim 1  further comprising a first lead-in section.  
     
     
         3 . The sensor of  claim 2  wherein the first lead-in section comprises an upper portion of a first sidewall of the channel, the first lead-in section tapers upwardly and outwardly from an intermediate portion of the first sidewall to the upper portion of the first sidewall.  
     
     
         4 . The sensor of  claim 1  wherein the first air baffle prevents an ultrasonic signal from traveling around the tube.  
     
     
         5 . The sensor of  claim 1  further comprising a second air baffle.  
     
     
         6 . The sensor of  claim 5  wherein the second air baffle is positioned between the signal emitting member and the signal receiving member.  
     
     
         7 . The sensor of  claim 6  wherein the second air baffle prevents an ultrasonic signal from traveling around the tube.  
     
     
         8 . The sensor of  claim 1  further comprising a second lead-in section positioned opposite the first lead-in section.  
     
     
         9 . The sensor of  claim 8  wherein the second lead-in section comprises an upper portion of a second sidewall of the channel, the second lead-in section tapers upwardly and outwardly from an intermediate portion of the second sidewall to the upper portion of the second sidewall.  
     
     
         10 . An air in-line sensor for detecting air bubbles in a therapeutic solution flowing through a tube, the sensor comprising: 
 a channel for receiving the tube having a first lead-in section, and a tube loading section;    a signal emitting member positioned on one side of the tube and a signal receiving member positioned on an opposite side of the tube; and,    a first air baffle positioned between the signal emitting member and the signal receiving member.    
     
     
         11 . The sensor of  claim 10  wherein the first lead-in section comprises an upper portion of a first sidewall of the channel, the first lead-in section tapers upwardly and outwardly from an intermediate portion of the first sidewall to the upper portion of the first sidewall.  
     
     
         12 . The sensor of  claim 10  wherein the first air baffle prevents an ultrasonic signal from traveling around the tube.  
     
     
         13 . The sensor of  claim 10  further comprising a second air baffle.  
     
     
         14 . The sensor of  claim 13  wherein the second air baffle is positioned between the signal emitting member and the signal receiving member.  
     
     
         15 . The sensor of  claim 14  wherein the second air baffle prevents an ultrasonic signal from traveling around the tube.  
     
     
         16 . The sensor of  claim 10  further comprising a second lead-in section positioned opposite the first lead-in section.  
     
     
         17 . The sensor of  claim 16  wherein the second lead-in section comprises an upper portion of a second sidewall of the channel, the second lead-in section tapers upwardly and outwardly from an intermediate portion of the second sidewall to the upper portion of the second sidewall.  
     
     
         18 . An air in-line sensor for detecting air bubbles in a therapeutic solution flowing through a tube located in a tube loader, the sensor comprising: 
 a channel for receiving the tube having a tube loading section; and,    the tube loader having a stationary section and a movable section hingedly connected to the stationary section, the movable section having a blade having a radius of curvature for positioning the tube in the tube loading section.    
     
     
         19 . The sensor of  claim 18  further comprising a signal emitting member positioned on one side of the tube and a signal receiving member positioned on an opposite side of the tube.  
     
     
         20 . The sensor of  claim 18  further comprising a first lead-in section.  
     
     
         21 . The sensor of  claim 20  wherein the first lead-in section comprises an upper portion of a first sidewall of the channel, the first lead-in section tapers upwardly and outwardly from an intermediate portion of the first sidewall to the upper portion of the first sidewall.  
     
     
         22 . The sensor of  claim 20  further comprising a second lead-in section positioned opposite the first lead-in section.  
     
     
         23 . The sensor of  claim 22  wherein the second lead-in section comprises an upper portion of a second sidewall of the channel, the second lead-in section tapers upwardly and outwardly from an intermediate portion of the second sidewall to the upper portion of the second sidewall.  
     
     
         24 . An air in-line sensor for detecting air bubbles in a therapeutic solution flowing through a tube located in a tube loader, the sensor comprising: 
 a channel for receiving the tube having a first lead-in section, and a tube loading section; and,    the tube loader having a stationary section and a movable section hingedly connected to the stationary section, the movable section having a blade having a radius of curvature for positioning the tube in the tube loading section.    
     
     
         25 . The system of  claim 24  further comprising a signal emitting member positioned on one side of the tube and a signal receiving member positioned on an opposite side of the tube.  
     
     
         26 . The sensor of  claim 24  wherein the first lead-in section comprises an upper portion of a first sidewall of the channel, the first lead-in section tapers upwardly and outwardly from an intermediate portion of the first sidewall to the upper portion of the first sidewall.  
     
     
         27 . The sensor of  claim 24  further comprising a second lead-in section positioned opposite the first lead-in section.  
     
     
         28 . The sensor of  claim 27  wherein the second lead-in section comprises an upper portion of a second sidewall of the channel, the second lead-in section tapers upwardly and outwardly from an intermediate portion of the second sidewall to the upper portion of the second sidewall.  
     
     
         29 . An air in-line sensor system for detecting air bubbles in a therapeutic solution flowing through a tube located in a pumping mechanism, the tube extending from a supply bag of the therapeutic solution to a patient through the system, the system comprising: 
 a channel for receiving the tube having a first lead-in section, and a tube loading section;    a signal emitting member positioned on one side of the tube and a signal receiving member positioned on an opposite side of the tube;    a first air baffle positioned between the signal emitting member and the signal receiving member; and,    the tube loader having a stationary section and a movable section hingedly connected to the stationary section, the movable section having a blade having a radius of curvature for positioning the tube in the tube loading section.    
     
     
         30 . The system of  claim 29  wherein the pumping mechanism is selected from the group consisting of a peristaltic pump, a roller pump, an expulsor pump, a finger pump and a piston cassette pump.  
     
     
         31 . The sensor of  claim 29  wherein the first lead-in section comprises an upper portion of a first sidewall of the channel, the first lead-in section tapers upwardly and outwardly from an intermediate portion of the first sidewall to the upper portion of the first sidewall.  
     
     
         32 . The sensor of  claim 29  wherein the first air baffle prevents an ultrasonic signal from traveling around the tube.  
     
     
         33 . The sensor of  claim 29  further comprising a second air baffle.  
     
     
         34 . The sensor of  claim 33  wherein the second air baffle is positioned between the signal emitting member and the signal receiving member.  
     
     
         35 . The sensor of  claim 34  wherein the second air baffle prevents an ultrasonic signal from traveling around the tube.  
     
     
         36 . The sensor of  claim 29  further comprising a second lead-in section positioned opposite the first lead-in section.  
     
     
         37 . The sensor of  claim 36  wherein the second lead-in section comprises an upper portion of a second sidewall of the channel, the second lead-in section tapers upwardly and outwardly from an intermediate portion of the second sidewall to the upper portion of the second sidewall.  
     
     
         38 . An air in-line sensor for detecting air bubbles in a therapeutic solution flowing through a tube, the sensor comprising: 
 means for emitting an ultrasonic signal through the tube;    means for preventing the ultrasonic signal from traveling around the tube;    means for detecting the ultrasonic signal emitted through the tube;    means for measuring the strength of the ultrasonic signal emitted through the tube;    means for comparing the strength of the ultrasonic signal to a preset voltage value;    means for outputting a preset, maximum value for liquid and a preset, minimum value for air; and,    means for determining whether to sound an air in-line alarm.    
     
     
         39 . The sensor of  claim 38  wherein the means for emitting is a transducer.  
     
     
         40 . The sensor of  claim 38  wherein the means for preventing employs two air baffles positioned between a signal emitting member and a signal receiving member.  
     
     
         41 . The sensor of  claim 38  wherein the means for detecting is a transducer.  
     
     
         42 . The sensor of  claim 38  wherein the means for measuring employs an electrical circuit.  
     
     
         43 . The sensor of  claim 38  wherein the means for comparing employs a voltage comparator.  
     
     
         44 . A method for loading a tube into a channel of a medical pump comprising the steps of: 
 providing a tube loader having a stationary section and a movable section, the movable section having a blade having a radius of curvature;    positioning the tube proximate the channel;    placing the blade in contact with the tube; and,    moving the blade until the tube is positioned within the tube loading section.    
     
     
         45 . The method of  claim 44  further comprising the step of providing an air sensor having a channel having a first lead-in section and a tube loading section, and a signal emitting member positioned on one side of the tube and a signal receiving member positioned on an opposite side of the tube.