Method and apparatus for detecting occlusion in fluid-infusion tube of peristaltic type fluid-infusion pump
First Claim
Patent Images
1. A method for detecting occlusion in a fluid-infusion tube of a peristaltic fluid-infusion pump, comprising:
- pressing respective wall portions of the fluid-infusion tube on inlet and outlet sides of the pump with substantially equal pressures during normal fluid infusing, by means of pressing means which includes a pair of pressing parts on a common movable member;
detecting a change in the position of said common movable member of said pressing means, said change being a result of a change in the difference between a first distance and a second distance, said first distance being defined by the distance between opposite wall portions of the fluid-infusion tube at said inlet side and being a function of the fluid pressure in the inlet portion of the tube; and
said second distance being defined by the distance between opposite wall portions of the tube at said outlet side and being a function of the fluid pressure in the outlet portion of the tube, the sum of said first and second distances always being constant; and
detecting an occlusion in the fluid-infusion tube from said detected change in position.
1 Assignment
0 Petitions
Accused Products
Abstract
A change in the internal pressure of the fluid-infusion tube of a peristaltic fluid-infusion pump due to occlusion in the fluid-infusion tube is detected through a change in the diameter of the fluid-infusion tube. The occlusion is detected by detection of the change in the distance between the opposite wall portions of the tube.
-
Citations
15 Claims
-
1. A method for detecting occlusion in a fluid-infusion tube of a peristaltic fluid-infusion pump, comprising:
-
pressing respective wall portions of the fluid-infusion tube on inlet and outlet sides of the pump with substantially equal pressures during normal fluid infusing, by means of pressing means which includes a pair of pressing parts on a common movable member; detecting a change in the position of said common movable member of said pressing means, said change being a result of a change in the difference between a first distance and a second distance, said first distance being defined by the distance between opposite wall portions of the fluid-infusion tube at said inlet side and being a function of the fluid pressure in the inlet portion of the tube; and
said second distance being defined by the distance between opposite wall portions of the tube at said outlet side and being a function of the fluid pressure in the outlet portion of the tube, the sum of said first and second distances always being constant; anddetecting an occlusion in the fluid-infusion tube from said detected change in position.
-
-
2. An apparatus for detecting occlusion in a fluid-infusion tube of a peristaltic fluid-infusion pump comprising:
-
a pair of stationary pieces respectively mounted adjacent said fluid-infusion tube at a fluid inlet portion and a fluid outlet portion of said fluid-infusion pump; a common movable member having a pair of pressing parts disposed respectively in opposition to said stationary pieces, said pressing parts being adapted to press the parts of said fluid-infusion tube which correspond to said fluid inlet and outlet portion of said pump, with a predetermined substantially equal pressure between said pressing parts and said respective associated stationary pieces during normal fluid infusing, said common movable member being adapted to be displaced corresponding to a change in a first distance between opposite wall portions of said fluid-infusion tube at said inlet portion thereof, and a change in a second distance at said outlet portion thereof, the sum of said first and second distances always being constant, said first and second distances being changed by a change in the internal pressure of said fluid-infusion tube caused by occlusion in said fluid-infusion tube; and means coupled to said common movable member for detecting said occlusion by detecting said displacement of said common movable member. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
Specification