Syringe for use in fluid-handling apparatus

• US 6,235,002 B1
• Filed: 04/17/1998
• Issued: 05/22/2001
• Est. Priority Date: 04/17/1998
• Status: Expired due to Term

• Current Assignee: Drew Scientific Holdings, Inc.
• Original Assignee: CDC Technologies, Inc. (Escalon Medical Corporation)
• Inventors: Antoci, Frank, Carver, Edward Lawrence Jr.
• Primary Examiner(s): Seidel, Richard K.
• Assistant Examiner(s): Thanh, LoAn H.
• Application Number:
  US09/062,107
• Time in Patent Office: 1,131 Days
• Field of Search: 604/181, 604/122-125, 604/131, 604/150, 604/173, 604/183, 604/194, 604/218, 604/231, 604/235, 604/187, 604/151, 604/152, 604/154, 604/221, 604/222, 604/236, 604/207, 604/68, 141/2, 141/18
• US Class Current: 604/183
• CPC Class Codes: B01L 3/0217 of the plunger pump type medical syringes A61M

Abstract

An improved displacement-type syringe has a housing, a substantially fixed seal, a solid or closed-tip plunger, an internal passageway formed between the housing and the plunger, and at least two ports on the housing with at least one port located at each end of the passageway for the passage of fluids and the elimination of gas. The syringe may be mounted in apparatus over a wide range of fixed inclination angles and remain substantially impervious to gas accumulation.

Claims

1. A syringe comprising:

an elongated housing defining a side wall, and an axially-elongated fluid passageway having a first end and a second end and extending through a substantial portion of the housing in an axial direction thereof;

at least one first fluid port located at approximately the first end of the passageway and coupled in fluid communication therewith for permitting the flow of fluid and gas into and out of the passageway;

at least one second fluid port located at approximately the second end of the passageway and coupled in fluid communication with the passageway and the first fluid port for permitting the flow of fluid and gas into and out of the passageway;

a plunger slidably received and movable through the housing between the first and second fluid ports for moving fluid into and out of the housing, wherein the axially-elongated passageway is formed between the plunger and the side wall of the housing and defines an unobstructed fluid-flow path connecting the first and second fluid ports in fluid communication with each other with the plunger located therebetween, to thereby allow gas within housing to flow out through at least one of the first and second fluid ports and prevent an accumulation of gas within the housing; and

a seal mounted on the housing and located between the at least one first fluid port and an adjacent end of the housing.

2. A syringe as defined in claim 1, wherein the plunger defines a solid exterior surface.

3. A syringe as defined in claim 1, wherein the port at the first end of the passageway defines a flow axis oriented radially with respect to an elongated axis of the housing.

4. A syringe as defined in claim 1, wherein the port at the second end of the passageway defines a flow axis oriented approximately parallel to an elongated axis of the housing.

5. A syringe as defined in claim 1, wherein the housing is substantially cylindrical.

6. A syringe as defined in claim 1, further comprising a threaded fitting mounted to the housing at the second end of the axially-elongated fluid passageway.

7. A syringe as defined in claim 1, wherein the plunger defines a tapered surface at a leading end thereof, and the housing further comprises an aperture located at the second end of the passageway and formed in fluid communication with the second fluid port for receiving the leading end of the plunger and forming a substantially fluid-tight seal.

8. A syringe as defined in claim 1, wherein the elongated housing defines an axially-extending interior wall, and the axially-elongated fluid passageway is formed, and further extends between the plunger and the axially-extending interior wall.

9. A syringe as defined in claim 1, wherein the syringe defines an axially-elongated housing, the first fluid port is located at approximately one end of the housing, and the second fluid port is located at approximately an opposite end of the housing.

10. A syringe comprising:

an elongated hollow housing;

a plunger slidably received through one end of the housing and spaced inwardly from an interior wall of the housing, the plunger being movable within the housing to move fluid into and out of the housing;

at least one first fluid port located at approximately one end of the housing and permitting the flow of fluid and gas into and out of the housing;

at least one second fluid port connected in fluid communication with the at least one first fluid port, and located at approximately an opposite end of the housing relative to the first fluid port, wherein the plunger is movable between the first and second fluid ports for moving fluid through at least one of the first and second fluid ports and into and out of the housing;

means defining an unobstructed fluid-flow path between the plunger and interior wall of the housing for maintaining the at least one first fluid port in fluid communication with the at least one second fluid port with the plunger located between the first and second fluid ports, and for allowing gas within the housing to flow out through at least one of the first and second fluid ports to thereby prevent an accumulation of gas within the housing; and

means for sealing mounted on the housing at approximately a first end of the unobstructed fluid-flow path.

11. A syringe as defined in claim 10, wherein the means for maintaining the first fluid port in fluid communication with the second fluid port and allowing gas to flow out through at least one of the ports to thereby prevent an accumulation of gas within the housing includes an axially-elongated passageway defined between the plunger and an interior wall of the housing, and extending between and coupled in fluid communication with the first and second fluid ports.

12. A syringe as defined in claim 11, wherein the housing defines an approximately cylindrical interior surface, and the axially-elongated passageway is formed between the plunger and the approximately cylindrical interior surface.

13. A syringe as defined in claim 10, wherein the plunger defines a solid exterior surface.

14. A syringe as defined in claim 10, wherein the means for sealing comprises at least one seal fixedly mounted at approximately one end of the housing, and defining an aperture with the plunger slidably received therethrough forming a substantially fluid-tight seal between the plunger and housing.

15. A syringe comprising:

an elongated housing defining a side wall, and an axially-elongated fluid passageway having a first end and a second end and extending through a substantial portion of the housing in an axial direction thereof;

a first fluid port located at approximately the first end of the passageway and coupled in fluid communication therewith for permitting the flow of fluid and gas into and out of the passageway;

a second fluid port located at approximately the second end of the passageway and coupled in fluid communication with the passageway and the first fluid port for permitting the flow of fluid and gas into and out of the passageway;

a plunger slidably received and movable through the housing between the first and second fluid ports for moving fluid into and out of the housing, wherein the axially-elongated passageway defines an unobstructed fluid-flow path connecting the first and second fluid ports in fluid communication with each other with the plunger located therebetween, to thereby allow gas within the housing to flow out through at least one of the first and second fluid ports and prevent an accumulation of gas within the housing; and

a seal fixedly mounted within the housing and located at approximately the first end of the axially-elongated fluid passageway.

16. A syringe as defined in claim 15, wherein the seal at the first end of the axially-elongated fluid passageway comprises at least one o-ring.

17. A method for preventing gas from accumulating within a syringe, wherein the syringe includes an elongated hollow housing, first and second fluid ports axially spaced relative to each other on the housing and connected in fluid communication with a hollow interior of the housing, a plunger slidably mounted within the hollow interior of the housing and movable between the first and second fluid ports for moving fluid through at least one of the ports and into and out of the housing, and an axially-elongated passageway formed between the plunger and an interior wall of the housing, and extending between and connecting the first and second fluid ports in fluid communication with each other with the plunger located between the first and second fluid ports, the method comprising the steps of:

introducing fluid into the hollow interior of the housing through at least one of the first and second fluid ports upon moving the plunger in a first direction between the first and second fluid ports;

directing gas within the fluid introduced into the hollow interior of the housing through the axially-elongated passageway and out of the housing through at least one of the first and second fluid ports;

directing fluid out of the housing through at least one of the first and second fluid ports upon moving the plunger in a second direction opposite the first direction between the first and second fluid ports; and

providing a seal mounted on the housing and located at approximately one end of the axially-elongated fluid passageway adjacent to one of the first and second fluid ports.

18. A method as defined in claim 17, further comprising the steps of mounting the syringe with one of the fluid ports located higher than the other fluid port, and directing any gas and fluid out of the housing through the higher fluid port.

19. A method as defined in claim 17, further comprising the steps of introducing fluid and gas into the hollow interior of the housing through one of the fluid ports, and directing fluid and gas out of the hollow interior of the housing through the other of the fluid ports.