Peristaltic Linear Pump and Method of Operation

Abstract

The present disclosure provides a linear peristaltic pump that is capable of dispensing varied amounts of liquid from a tube. The linear peristaltic pump includes an adjustably attached squashing plate that is configured to move lengthwise in the housing of the pump. The amount of liquid dispensed from a tube disposed in the pump varies based on the location of the squash plate in the housing.

What is claimed is: 
     
         1 . A peristaltic linear pump to dispense a varied volume of liquid from a tube, comprising:
 a base plate with at least a first groove formed in a top surface of the base plate, the first groove configured to hold a first tube in a lengthwise direction;   a first bump formed at a first end of the base plate and in the first groove, the first bump extending above the first groove;   a downstream valve configured to prevent liquid in the first tube from flowing upstream,   a housing include a first movable arm disposed lengthwise in the housing;   a first squash plate adjustably fixed in the first movable arm and configured to move lengthwise in the first movable arm, the first movable arm having a greater length than the first squash plate, wherein the first squash plate is configured to squash a portion of the first tube, the portion of the squashed first tube extending from a downstream end of the first squash plate to the first bump;   wherein an amount of liquid dispensed from the first tube by the pump varies based upon a location of the first squash plate in the movable arm.   
     
     
         2 . The linear pump of  claim 1 , further comprising:
 a first linear actuator configured to move the first squash plate in a vertical direction, such that the first squash plate is configured to first squash the tube at the first bump and then configured to continue rotating the first squash plate downward to squash the squashed portion of the tube.   
     
     
         3 . The linear pump of  claim 1 , further comprising the first tube,
 wherein the first bump extends above the lower surface of the first groove by a vertical distance of 10 to 80% of the uncompressed diameter of the first tube.   
     
     
         4 . The linear pump of  claim 1 , wherein the base plate further comprises a second groove, the second groove configured to hold a second tube in a lengthwise direction; and
 wherein a second bump is formed at a first end of the base plate and in the second groove, the second bump extending above the first groove.   
     
     
         5 . The linear pump of  claim 4 , further comprising a second squash plate adjustably fixed in a first movable arm of the housing and configured to move in a lengthwise direction in the housing, wherein a length of the first movable arm is greater than a length of the second squash plate, and wherein the second squash plate is configured to squash a portion of the second tube, the portion of the squashed second tube extending from a downstream end of the second squash plate to the first bump. 
     
     
         6 . The linear pump of  claim 5 , further comprising a second linear actuator configured to move the second squash plate in a vertical direction, such that the second squash plate is configured to first squash the tube at the first bump and then configured to continue rotating the second squash plate downward to squash the squashed portion of the second tube. 
     
     
         7 . The linear pump of  claim 4 , wherein the first tube is a different size than the second tube. 
     
     
         8 . The linear pump of  claim 4 , wherein the first squash plate is configured to squash a portion of the second tube, the portion of the squashed second tube extending from a downstream end of the second squash plate to the second bump. 
     
     
         9 . The linear pump of  claim 4 , wherein a depth of the first groove is different from a depth of the second groove. 
     
     
         10 . The linear pump of  claim 1 , wherein a depth of the first groove is larger at a downstream end than at an upstream end of the first groove. 
     
     
         11 . A peristaltic linear pump to dispense a varied volume of liquid from a tube, comprising:
 a base plate with at least a first groove formed in a top surface of the base plate, the first groove configured to hold a first tube in a lengthwise direction;   a first bump formed at a first end of the base plate and in the first groove, the first bump extending above the first groove;   a downstream valve configured to prevent liquid in the first tube from flowing upstream,   a housing include a first movable arm disposed lengthwise in the housing;   a first plate adjustably fixed in the first movable arm, the first movable arm having a greater length than the first plate, wherein the first plate is configured to compress a portion of the first tube, the portion of the compressed first tube extending from a downstream end of the first plate to the first bump;   wherein an amount of liquid dispensed from the first tube by the pump varies based upon a location of the first plate in the first movable arm.   
     
     
         12 . The linear pump of  claim 11 , wherein a bottom surface of the first plate is curved. 
     
     
         13 . The linear pump of  claim 11 , wherein a bottom surface of the first plate is flat. 
     
     
         14 . The linear pump of  claim 11 , further comprising an actuator coupled to the movable arm, the actuator configured to move the movable arm along a vertical axis. 
     
     
         15 . A peristaltic linear pump to dispense a varied volume of liquid from a tube, comprising:
 a housing including an adjustably attached flattening bar;   a bottom plate with at least a first trench formed therein, the first trench configured to hold a first tube in a lengthwise direction, the flattening bar and bottom plate being positioned within the housing to be movable relative to each other;   a first protrusion extending upwardly from an upstream end of the first trench;   a first pincher disposed at a downstream end of the first trench, the first pincher configured to prevent liquid in the first tube from flowing upstream;   wherein the flattening bar is configured to close a portion of the first tube from the first protrusion to a downstream end of the flattening bar such that the first pincher is opened and the liquid in the closed portion of the first tube is dispensed, and   wherein an amount of liquid dispensed from the first tube by the pump varies based upon a relative positioning of the flattening bar and bottom plate.   
     
     
         16 . The pump of  claim 15 , further comprising:
 a second trench formed in the bottom plate, the second trench configured to hold a second tube in a lengthwise direction;   a second protrusion extending upwards from an upstream end of the second trench; and   a second pincher configured to prevent liquid in the second tube from flowing upstream.   
     
     
         17 . The pump of  claim 15 , wherein the flattening plate is configured to close a portion of the second tube from the second protrusion to a downstream end of the flattening bar such that the second pincher is opened and the liquid in the closed portion of the second tube is dispensed. 
     
     
         18 . The pump of  claim 15 , further comprising a second adjustably attached flattening plated disposed in the housing, the second flattening plate configured to close a portion of the second tube from the second protrusion to a downstream end of the second flattening bar such that the second pincher is opened and the liquid in the closed portion of the second tube is dispensed. 
     
     
         19 . A method of dispensing a varied volume of liquid from a tube using a linear peristaltic pump, comprising the steps of:
 placing a tube in a groove of the pump, the groove having a bump at an upstream end of the groove and a pinching valve at the downstream end of the groove;   rotating a squash plate downward such that the squash plate closes the tube at the bump;   dispensing a volume of liquid from the tube by rotating the squash plate further downward such that the squash plate closes the tube from the bump to the pinching valve,   wherein a length of the tube that is closed by the squash plate is adjustable.