Peristaltic dialysate solution pump
First Claim
1. Peristaltic pump means for use in hemodialysis apparatus, comprising a rotatable pump head assembly including a base member positioned for rotation about a fixed axis with four circumferentially spaced apart rollers mounted thereon for independent rotation about respective axes parallel to the base member fixed axis;
- flexible resilient tubing through which a negative pressure fluid is pumped;
means for anchoring end segments of the flexible resilient tubing such that the tubing is tensionally extended around the pump head assembly, being simultaneously engaged and compressed by at least two of said circumferentially spaced apart rollers, said rollers being mounted for longitudinal movement of the points of compression along the tubing during rotation of said pump head assembly to advance fluid through said tubing;
each of said four rollers having a generally convex surface profile, for only partial closure of the tubing at the points of compression by said rollers, and circumferentially spaced 90°
apart from adjacent rollers;
said flexible resilient tubing having a length, as measured longitudinally along the tubing between the anchored end segments thereof, of from 6.75 to 11.0 inches, a wall thickness no greater than 0.125 inch, and an internal diameter no greater than 0.35 inch; and
drive means coupled to said pump head assembly for rotation thereof.
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Accused Products
Abstract
Peristaltic pump means for pumping dialysate solution through a dialysate solution flow circuit in a hemodialysis system. The pump comprises four rollers mounted on a rotatable base member with a relatively long segment of flow circuit tubing tensionally extended around the pump head so as to be simultaneously engaged and compressed by at least two of the rollers, the rollers being mounted for longitudinal movement of the points of compression along the tubing during rotation of the pump head assembly to advance dialysate solution through the flow circuit. The disclosed pump means provides a substantially uniform dialysate solution flow rate under conditions of varying dialysate solution negative pressure and is particularly suitable for use in a unitary, portable hemodialysis module of a type adapted for coupling with either a single-pass proportioning system or a batch dialysate solution supply. A proportioning system is disclosed for such arrangement which employs a recirculating deaeration means for removal of soluble gases from the water employed for make-up of dialysate solution. The peristaltic dialysate solution pump is mounted in the portable hemodialysis module in a manner which facilitates rapid changeover from single-pass to batch dialysate solution flow, and vice versa.
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Citations
18 Claims
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1. Peristaltic pump means for use in hemodialysis apparatus, comprising a rotatable pump head assembly including a base member positioned for rotation about a fixed axis with four circumferentially spaced apart rollers mounted thereon for independent rotation about respective axes parallel to the base member fixed axis;
- flexible resilient tubing through which a negative pressure fluid is pumped;
means for anchoring end segments of the flexible resilient tubing such that the tubing is tensionally extended around the pump head assembly, being simultaneously engaged and compressed by at least two of said circumferentially spaced apart rollers, said rollers being mounted for longitudinal movement of the points of compression along the tubing during rotation of said pump head assembly to advance fluid through said tubing;
each of said four rollers having a generally convex surface profile, for only partial closure of the tubing at the points of compression by said rollers, and circumferentially spaced 90°
apart from adjacent rollers;
said flexible resilient tubing having a length, as measured longitudinally along the tubing between the anchored end segments thereof, of from 6.75 to 11.0 inches, a wall thickness no greater than 0.125 inch, and an internal diameter no greater than 0.35 inch; and
drive means coupled to said pump head assembly for rotation thereof. - View Dependent Claims (2, 3, 4)
- flexible resilient tubing through which a negative pressure fluid is pumped;
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5. Hemodialysis apparatus for treatment of blood to remove waste impurities therefrom, including:
- dialyzer means through which waste impurity-containing blood and a dialysate solution are passed in indirect mass transfer dialyzing relationship for transfer of said waste impurities from said blood to said dialysate solution;
means for transferring waste impurity-containing blood from a patient to said dialyzer means including a flexible resilient tubing pumping section through which blood is pumped and means for returning waste impurity-depleted blood to said patient forming a blood flow circuit;
means for transferring dialysate solution from a negative pressure dialysate solution source to said dialyzer means and means for discharging waste impurity-enriched dialysate solution from said dialyzer means forming a dialysate solution flow circuit including a flexible resilient tubing pumping section through which dialysate solution is pumped;
peristaltic blood pump means disposed in said blood flow circuit and peristaltic dialysate pump means disposed in said dialysate solution flow circuit each pump means comprising a rotatable pump head assembly including a base member positioned for rotation about a fixed axis with a plurality of circumferentially spaced apart rollers mounted thereon for independent rotation about respective axes parallel to the base member fixed axis, at least said peristaltic dialysate pump means having four spaced apart rollers mounted on the base member thereof;
means for anchoring the end segments of the flexible resilient tubing pumping section in said blood flow circuit and means for anchoring the end segments of the flexible resilient tubing pumping section in said dialysate solution flow circuit such that the tubing in each circuit is tensionally extended around the pump head assembly of a respective one of said peristaltic pump means and is simultaneously engaged and compressed by at least two of said circumferentially spaced apart rollers of the respective peristaltic pump means, the rollers of each peristaltic pump means being mounted for longitudinal movement of the points of compression along the associated tubing during rotation of said pump head assembly to advance fluid through said tubing;
each of said four rollers in at least the peristaltic dialysate pump means having a generally convex surface profile, for only partial closure of the tubing at the points of compression by the rollers, with a maximum diameter between 0.25 and 0.75 inch and circumferentially spaced 90°
apart from adjacent rollers with a radial distance between the roller axis and said base member fixed axis of from 0.50 to 1.50 inches;
said flexible resilient tubing pumping section in the dialysate flow circuit having a length, as measured longitudinally along the tubing between the anchored end segments thereof, of from 6.75 to 11.0 inches, a wall thickness of from 0.07 to 0.125 inch, and an internal diameter of from 0.18 to 0.35 inch; and
drive means coupled to the pump head assembly of the peristaltic dialysate pump means for rotation thereof at a speed in the range of from 150 to 400 rpm. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
- dialyzer means through which waste impurity-containing blood and a dialysate solution are passed in indirect mass transfer dialyzing relationship for transfer of said waste impurities from said blood to said dialysate solution;
Specification