| 摘要 |
An ultrasonic device for detecting the presence of air in the fluid line of an IV infusion device comprises a transmitter and a receiver which are, positioned to pinchingly engage a portion of the fluid line therebetween. Both the transmitter and receiver have convex-shaped lenses which contact and cause a slight indentation of the tube for enhanced coupling therebetween. The device may also have a pair of diametrically opposed pedestals which contact and engage the tube from a direction substantially at right angles to the axis defined by the transmitter and receiver. These pedestals help hold the tube between the transmitter and receiver. The device also includes self-testing electronic componentry which compares the transmitter-off output with the transmitter-on output to determine whether operation is normal or should be stopped because either there is air in the line or the electronic circuitry is faulty. |
