Volumetric pump
In one embodiment, a volumetric pump in a medical fluid delivery system comprises at least one piston in a hollow cylinder, the pump having at least one inlet port through which a medical fluid can be sucked into a pump chamber during an instroke of said piston, and at least one outlet port through which the medical fluid can be expelled during an outstroke of the piston. The piston or the hollow cylinder can be actuated directly or indirectly by a rotor. This rotor transmits on the one hand a bi-directional linear movement to the piston or to the cylinder and on the other hand, a bi-directional angular movement either to the piston or to another ratable element in order to open and close alternately the inlet and outlet ports.
1. A medical fluid delivery system comprising a volumetric pump, the pump comprising at least one first piston inside a first hollow cylindrical part, said pump having at least one inlet port through which a medical fluid can flow into at least one pump chamber, and at least one outlet port through which the medical fluid can be expelled, at least one second piston being positioned opposite to the first piston inside a second hollow cylindrical part, both cylindrical parts being assembled end-to-end facing each other to form a housing, the housing being ultimately driven by a drive link in a bidirectional linear movement to cause sliding between the housing and the pistons along an axis of said pistons, a disc being mounted midway inside said housing, said disc comprising fluid ports, the disc including a receptacle to receive a drive member, wherein linear movement of the drive member causes bidirectional angular movement of the disc to selectively align the disc fluid ports with the inlet and outlet ports in a synchronized fashion with the bidirectional linear movement of the housing to provide a substantially continuous delivery of medical fluid to a patient, wherein the medical fluid comprises at least a contrast medium.
2. The medical fluid delivery system according to claim 1 , wherein the at least one first piston and the at least one second piston each have at least two over-molded circumferential sealing members.
3. The medical fluid delivery system according to claim 1 , wherein a portion of said housing, near the assembly of the first and second cylindrical parts, is rectangular in shape.
4. The medical fluid delivery system of claim 2 , wherein the at least one first piston and the at least one second piston each have an outer surface that contacts the medical fluid in use, and each of the at least two over-molded circumferential sealing members extend circumferentially beyond the outer surface of the at least one first piston and the at least one second piston to contact the first and second hollow cylindrical parts, respectively.
5. The medical fluid delivery system according to claim 1 , further comprising one or more reservoirs of contrast media coupled to the pump.
6. The medical fluid delivery system according to claim 5 , further comprising a spike/drip chamber assembly coupled to each of the one or more reservoirs of contrast media.
7. The medical fluid delivery system according to claim 5 , further comprising a valve located between the one or more reservoirs of contrast media and the pump.
8. The medical fluid delivery system according to claim 1 , further comprising an air/pressure sensor coupled to the pump.
9. The medical fluid delivery system according to claim 1 , wherein the system is a powered contrast injection system.
10. The medical fluid delivery system according to claim 1 , further comprising a reservoir of diluent coupled to the pump.
11. The medical fluid delivery system of claim 1 , wherein a portion of said housing, near the assembly of the first and second cylindrical parts, is rectangular in shape.
12. The medical fluid delivery system according to claim 1 , wherein the receptacle comprises a socket to receive a ball-shaped end of the drive member.
13. The medical fluid delivery system according to claim 1 , wherein movement of the drive member is perpendicular to movement of the drive link.