Hydraulic pump with replaceable pumping member

• US 4,012,178 A
• Filed: 02/25/1975
• Issued: 03/15/1977
• Est. Priority Date: 04/16/1973
• Status: Expired due to Term

• Current Assignee: Benjamin V. Puckett
• Original Assignee: Benjamin V. Puckett
• Inventors: Puckett, Benjamin V.
• Primary Examiner(s): Croyle, Carlton R.
• Assistant Examiner(s): Ross, Thomas I.
• Application Number:
  US05/552,927
• Time in Patent Office: 749 Days
• Field of Search: 417/478, 417/479, 417/394, 417/567, 417/568, 285/347
• US Class Current: 417/478
• CPC Class Codes: A61M 1/3621 Extra-corporeal blood circuits single-needle circuits A61M1/30
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/37 Haemodialysis, haemofiltration or diafiltration
• CPC Class Codes: A61M 60/427 the force acting on the blood contacting member being hydraulic or pneumatic
• CPC Class Codes: A61M 60/531 using blood pressure data, e.g. from blood pressure sensors
• CPC Class Codes: A61M 60/837 Aspects of flexible displacement members, e.g. shapes or materials
• CPC Class Codes: A61M 60/849 Disposable parts
• CPC Class Codes: A61M 60/851 Valves
• CPC Class Codes: A61M 60/892 Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: F04B 43/107 the fluid being actuated directly by a piston
• CPC Class Codes: F04B 49/12 by varying the length of stroke of the working members
• CPC Class Codes: F04B 9/02 the means being mechanical

Abstract

A hydraulic pump particularly suited for the extracorporal circulation of blood, having a readily replaceable and disposable pumping member is disclosed. The pump avoids injury to the blood cells and creates a minimum of turbulence during the pumping operation, thus limiting the buildup of fibrin.

Claims

1. A hydraulic pump comprising a casing and a pumping unit comprising:

a. a fluid impermeable elastic tubular member;

b. a first and second pair of sealing rings sealingly connected to said elastic tubular member, each pair having;

3. The apparatus of claim 1 in which said inlet valve comprises:

a. said inner tubular ring having a section of reduced inner diameter

b. at least one projection extending radially inwardly into the interior of said inner tubular ring at a point proximate the interior of said elastic tubular member,

c. a ball located within said inner tubular ring, said ball having a diameter larger than the reduced inner diameter portion of said inner tubular ring, said ball restrained by said projections from entering said elastic tubular member.

4. The apparatus of claim 1 in which said outlet valve comprises:

a. said inner tubulor ring having a section of reduced inner diameter proximate the interior of said elastic tubular member,

b. a connecting extension tubular member having a first section with an outer diameter slightly smaller than the large inner diameter of the inner tubular ring, said section fited within the inner tubular ring, and a second portion of said connecting extension tubular member having an inner diameter smaller than the inner diameter of the portion of the connecting extension tubular member inserted within the inner tubular ring,

c. at least one projection extending radially into the interior of the connecting entension tubular member at a point away from said elastic tubular member,

d. a ball located within said connecting extension tubular member having a diameter larger than said reduced diameter section of the inner ring and restrained by said projections from entering the reduced inner diameter of the connecting extension tubular member.

5. The apparatus of claim 3 in which said at least one projection extending radially into the interior of the inlet and outlet valves comprises at least three pins.

6. The apparatus of claim 3 in which said at least one projection extending radially into the interior of the inlet and outlet valves comprises at least three pins.

7. The apparatus of claim 5 in which said pins are symmetrically spaced from one another.

8. The apparatus of claim 1 in which said means for aligning and holding said sealing rings in said casing is a skirt on the outer tubular ring of each sealing ring, said skirt projecting radially outward from said outer tubular ring.

2. an outer tubular ring surrounding a portion of the outer wall of said elastic tubular member, said outer tubular ring including means for aligning and holding said sealing rings in said casing;

2. an inner tubular ring within said elastic tubular member and having an annular groove around the outer circumference of said inner tubular ring;

3. an O-ring within said annular grooves of said first and second inner tubular rings, said O-rings being in fluid sealing engagement with the inner surface of said elastic tubular member;

c. said first pair of sealing rings having an inlet valve within the inner tubular ring, and

d. said second pair of sealing rings having an outlet valve within the inner tubular ring, said elastic tubular member and said first and second pair of sealing rings defining a disposable unit which may be inserted in, or removed from the interior chamber of said casing which comprises means for creating alternately positive and negative pressure within the chamber to intermittently expand said elastic tubular member in said interior chamber.