Abstract: An infusion pump (100) includes a plunger (110) configured to squeeze a section of an infusion tube (150). A proximal valve (120), proximal to the plunger, ascends to allow infusion fluid intake from a reservoir to the infusion tube and descends to inhibit infusion fluid intake from the reservoir to the infusion tube. A distal valve (125), distal to the plunger, ascends to allow infusion fluid flow past the distal valve, and descends to inhibit infusion fluid flow past the distal valve. A controller (141) controls the plunger, proximal valve, and distal valve by initiating descending of the plunger concurrently with or prior to the ascending of the distal valve, such that the descending of the plunger compensates for suction produced by the ascending of the distal valve, thereby reducing backflow of fluid from the subject. Other applications are also described.

Abstract: A tube cassette (22) for receiving infusion tubing is shaped to define a locking surface (26). A pump (20) includes a latch (28) which engages with the locking surface and locks the cassette in a preset position with respect to the pump. A mechanical stop (38) in the pump stops motion of the cassette in a first direction, such that the cassette has moved past the preset position. Until motion of the cassette is stopped by the mechanical stop, the latch allows motion of the cassette past the preset position in the first direction. The latch automatically moves from an open position to a cassette-withdrawal-inhibiting position upon engagement of the latch with the locking surface, and subsequently locks the cassette in the preset position by pushing the cassette in a second direction, from past the preset position to the preset position. Other applications are also described.

Abstract: An infusion pump including a plunger, a proximal valve located proximally to the plunger, a distal valve located distally to the plunger, and a controller configured to trigger the position of the plunger, such that both in its upper position and its lower position, the plunger squeezes a section of an infusion tube, such that opposite sides of an inner surface of the section do not contact one another.

Abstract: An infusion pump (100) includes a plunger (110) configured to squeeze a section of an infusion tube (150). A proximal valve (120), proximal to the plunger, ascends to allow infusion fluid intake from a reservoir to the infusion tube and descends to inhibit infusion fluid intake from the reservoir to the infusion tube. A distal valve (125), distal to the plunger, ascends to allow infusion fluid flow past the distal valve, and descends to inhibit infusion fluid flow past the distal valve. A controller (141) controls the plunger, proximal valve, and distal valve by initiating descending of the plunger concurrently with or prior to the ascending of the distal valve, such that the descending of the plunger compensates for suction produced by the ascending of the distal valve, thereby reducing backflow of fluid from the subject. Other applications are also described.

Abstract: A tube cassette (22) for receiving infusion tubing is shaped to define a locking surface (26). A pump (20) includes a latch (28) which engages with the locking surface and locks the cassette in a preset position with respect to the pump. A mechanical stop (38) in the pump stops motion of the cassette in a first direction, such that the cassette has moved past the preset position. Until motion of the cassette is stopped by the mechanical stop, the latch allows motion of the cassette past the preset position in the first direction. The latch automatically moves from an open position to a cassette-withdrawal-inhibiting position upon engagement of the latch with the locking surface, and subsequently locks the cassette in the preset position by pushing the cassette in a second direction, from past the preset position to the preset position. Other applications are also described.

Abstract: An infusion pump includes upstream and downstream valves, a pressing surface disposed between the valves which presses on an infusion tube, a pressure sensor which measures pressure within the infusion tube, and a controller. In response to the pressure, the controller determines that there is an occlusion in the infusion tube downstream of the downstream valve, and in response thereto, toggles the upstream valve and the downstream valve. The toggling includes sequentially, (a) while the upstream valve remains closed, isolating a segment of the infusion tube between the valves by closing the downstream valve, (b) while the downstream valve remains closed, reducing pressure in the isolated segment by opening the upstream valve, (c) while the downstream valve remains closed, closing the upstream valve, and (d) while the upstream valve remains closed, reducing pressure downstream of the downstream valve by opening the downstream valve. Other applications are also described.

Abstract: An infusion pump includes inlet and outlet valves and a squeezing element configured to squeeze a fluid line coupled to the infusion pump. A method includes at least one round of valve operation check prior to initiation of a delivery session of fluid to a subject, and subsequently, after an intake phase and before a delivery phase of at least one infusion pump cycle, determining for the at least one pump cycle, an absolute amount of air in the fluid line. The valve operation check and the determining of the amount of air each include: (A) closing the inlet valve to confine a section of the fluid line between the inlet and outlet valves; (B) squeezing the confined section; (C) measuring the pressure within the confined section; and (D) subsequently, relieving the pressure in the confined section. Other applications are also described.

Abstract: An infusion pump including a plunger, a proximal valve located proximally to the plunger, a distal valve located distally to the plunger, and a controller configured to trigger the position of the plunger, such that both in its upper position and its lower position, the plunger squeezes a section of an infusion tube, such that opposite sides of an inner surface of the section do not contact one another.

Abstract: An infusion pump includes inlet and outlet valves and a squeezing element configured to squeeze a fluid line coupled to the infusion pump. A method includes at least one round of valve operation check prior to initiation of a delivery session of fluid to a subject, and subsequently, after an intake phase and before a delivery phase of at least one infusion pump cycle, determining for the at least one pump cycle, an absolute amount of air in the fluid line. The valve operation check and the determining of the amount of air each include: (A) closing the inlet valve to confine a section of the fluid line between the inlet and outlet valves; (B) squeezing the confined section; (C) measuring the pressure within the confined section; and (D) subsequently, relieving the pressure in the confined section. Other applications are also described.

Abstract: Disclosed is a medical device including a housing which may receive an interface unit body which may include at least one flexible segment, a therapeutic component which may apply a force to cause fluid to flow through the flexible segment and a sensor to (1) detect if the interface unit body corresponds to said housing and (2) disable said therapeutic component if the interface unit body is non-corresponding.