High pressure pumping cartridges for medical and surgical pumping and infusion applications
Pumping cartridges useful for medical and surgical pumping and infusion procedures. In one aspect, a series of pumping cartridges include cylinders and pistons which have a sealing component including a circumferential, flared sealing flange and can be configured to enable the pumping cartridge to generate high liquid pumping pressures. Many of the pumping cartridges can be configured to be detachable from a pump drive unit and disposable after a single use. Some pistons include or at least partially form a valve and/or are relatively movable with respect to a connected piston rod. Valves include a valve seat and a movable sealing element able to create a seal capable of withstanding differences in fluid pressures thereacross of at least about 1,000 psi. The movable sealing element is concave in shape, and may be curved for improved sealing performance. Methods for pumping or infusing a liquid for delivery to the body of a patient or a surgical or medical instrument.
1. A pumping cartridge comprising:
a cylinder; and a piston rod constructed and arranged for reciprocating motion with respect to the cylinder, the pumping cartridge including therein a sealing component shaped to include a circumferential, flared sealing flange portion extending away from a portion to which it is attached, of a sealing component support element, such that a first surface of the flared sealing flange portion adjacent to and facing a surface with which it is in sliding contact forms a first angle with respect to the longitudinal axis of the cylinder and a second surface of the flared sealing flange portion facing away from the surface with which it is in sliding contact forms a second angle with respect to the longitudinal axis of the cylinder, where the first angle exceeds 0 degrees, the second angle does not exceed 90 degrees, the second angle exceeds the first angle, and
the sealing flange portion of the sealing component is constructed of a non-elastomeric material, the flared sealing portion is essentially irreversibly deformed during sliding motion of the piston rod relative to the cylinder.
2. The pumping cartridge as in claim 1 , further comprising a piston coupled to the piston rod, wherein the piston includes the sealing component shaped to include the circumferential, flared sealing flange portion, the flared sealing flange portion extending away from a portion, to which it is attached, of a main body of the piston, such that the first surface of the flared sealing flange portion is adjacent to and faces an inner surface of the cylinder to form the first angle with respect to the longitudinal axis of the cylinder and the second surface of the flared sealing flange portion faces the cylinder bore to form the second angle with respect to the longitudinal axis of the cylinder.
3. The pumping cartridge as in claim 1 , wherein the cylinder includes the sealing component shaped to include the circumferential, flared sealing flange portion, the flared sealing flange portion extending away from a portion, to which it is attached, of a cylinder-engaging main body portion of a sealing ring coupled to the cylinder, such that the first surface of the flared sealing flange portion is adjacent to and faces the piston to form the first angle with respect to the longitudinal axis of the cylinder and the second surface of the flared sealing flange portion faces an inner surface of the cylinder to form the second angle with respect to the longitudinal axis of the cylinder.
4. The pumping cartridge as in claim 1 , wherein the cylinder includes the sealing component shaped to include the circumferential, flared sealing flange portion, the flared sealing flange portion extending away from a portion, to which it is attached, of an inner surface of the cylinder, such that the first surface of the flared sealing flange portion is adjacent to and faces the piston to form the first angle with respect to the longitudinal axis of the cylinder and the second surface of the flared sealing flange portion faces an inner surface of the cylinder to form the second angle with respect to the longitudinal axis of the cylinder.
5. The pumping cartridge as in claim 2 , wherein the piston includes at least part of a valve.
6. The pumping cartridge as in claim 5 , wherein the valve included in the piston is constructed and positioned to act as an inlet valve to the cylinder of the fluid being pumped by the pumping cartridge when it is in operation.
7. The pumping cartridge as in claim 1 , wherein a proximal end of the cylinder has a beveled inner surface.
8. The pumping cartridge as in claim 2 , wherein the sealing component is integrally formed with the main body of the piston and both the main body of the piston and the sealing component are formed of the same polymeric material.
9. The pumping cartridge as in claim 8 , wherein the sealing component and the main body of the piston are injection molded as one piece.
10. The pumping cartridge as in claim 1 , wherein the flared sealing flange portion has a predefined length and extends both axially and radially away from the portion of the sealing component support element to which it is attached so as to form a cantilevered circumferential flange thereon.
11. The pumping cartridge as in claim 10 , wherein the sealing flange portion extends axially away from the portion of the sealing component support element to which it is attached by a distance of between about 0.01 inch and about 0.2 inch.
12. The pumping cartridge as in claim 2 , wherein the maximum axial thickness of the piston is between about 0.04 inch and about 0.32 inch.
13. The pumping cartridge as in claim 2 , wherein the pumping cartridge is constructed and arranged so that the piston reciprocates within an essentially immobile cylinder.
14. The pumping cartridge as claimed in claim 13 , wherein the flared sealing flange portion of the piston has a predefined length and extends both axially and radially away from the portion of the main body of the piston to which it is attached so as to form a cantilevered circumferential flange thereof, and wherein the sealing flange portion of the piston has a maximum outer diameter large enough to enable at least a portion of the sealing flange to be in essentially continuous contact with an inner surface of the cylinder during reciprocation of the piston.
15. The pumping cartridge as in claim 14 , wherein the sealing flange portion of the piston has a maximum-outer diameter, when in a relaxed configuration prior to insertion into the cylinder upon assembly of the pumping cartridge, exceeding a maximum outer diameter of the main body of the piston.
16. The pumping cartridge as in claim 15 , wherein the sealing flange portion of the piston has a maximum outer diameter, when in a relaxed configuration prior to insertion into the cylinder upon assembly of the pumping cartridge, exceeding a maximum outer diameter of the main body of the piston by at least about 1%.
17. The pumping cartridge as in claim 14 , wherein a portion of the cylinder in which the piston reciprocates has an inner diameter exceeding the maximum outer diameter of the main body of the piston.
18. The pumping cartridge as in claim 17 , wherein the portion of the cylinder in which the piston reciprocates has an inner diameter less than a maximum outer diameter of the sealing flange portion of the piston, by at least about 1% when it is in a relaxed configuration prior to insertion into the cylinder upon assembly of the pumping cartridge.
19. The pumping cartridge as in claim 14 , wherein the piston is annular in shape with a centrally disposed bore therethrough defining a fluid flow path.
20. The pumping cartridge as in claim 1 , where in the first angle is between about 1 degree and about 20 degrees.
21. The pumping cartridge as in claim 1 , wherein the second angle is between about 10 degrees and about 80 degrees.
22. The pumping cartridge as in claim 20 , wherein the second angle is between about 10 degrees and about 80 degrees.
23. The pumping cartridge as in claim 20 , wherein the first angle is between 3 degrees and 12 degrees and the second angle is between 15 degrees and 30 degrees.