Disposable syringe and cartridge with pneumatic chamber

• US 7,267,668 B2
• Filed: 04/23/2003
• Issued: 09/11/2007
• Est. Priority Date: 11/30/2001
• Status: Expired due to Fees

• Current Assignee: Philip H. Ruben
• Original Assignee: Philip H. Ruben
• Inventors: Ruben, Philip H.
• Primary Examiner(s): DESANTO, MATTHEW F
• Application Number:
  US10/421,588
• Publication Number:
  US 20030195477A1
• Time in Patent Office: 1,602 Days
• Field of Search: 604/82, 604 88- 91, 604/187, 604/221, 604/222, 604/227, 604/228, 604/233, 604/223, 604/181, 604/232
• US Class Current: 604/187
• CPC Class Codes: A61M 5/31513 Piston constructions to improve sealing or sliding
• CPC Class Codes: A61M 5/484 Regulating injection pressure
• CPC Class Codes: B01L 2400/0478 pistons
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 3/021 Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
• CPC Class Codes: B01L 3/0217 of the plunger pump type medical syringes A61M

Abstract

A syringe or cartridge having a hollow barrel with an open end and a second end suitable for attaching a needle assembly. A master plunger assembly that includes a master plunger and a plunger member is mounted in the barrel for longitudinal movement therein. A slave plunger is mounted in the barrel for longitudinal movement therein, and is located between the master plunger assembly and the second barrel end so as to define two chambers. The first chamber a liquid chamber and is between the slave plunger and the second barrel end, and the second chamber is a pneumatic chamber and is between the slave plunger and the master plunger assembly. The liquid-containing chamber is suitable for containing a liquid to be dispensed from the syringe, and the pneumatic chamber contains a gas such as air. When the liquid-containing chamber contains a liquid to be dispensed, a user applying selective pressure to the plunger member will cause the master plunger assembly to slide towards the slave plunger and compress the gas against the slave plunger. The slave plunger will as a result of this pressure slide towards the second barrel end as the gas decompresses and apply pressure against the liquid as a result thereof. The liquid will then be dispensed out of the syringe or cartridge via a needle attached to the barrel end.

Claims

1. A syringe comprising:

a) a hollow barrel comprising a first barrel end and a second barrel end, said first barrel end being open and said second barrel end comprising means for allowing attachment of a needle assembly, said barrel having a first chamber and a second chamber of substantially equal diameters;

b) said first chamber accommodating a non-therapeutic compressible gas which is not to be dispensed out of said first chamber;

c) said second chamber accommodating a therapeutic fluid capable of being dispensed out of said second chamber;

d) a master plunger assembly mounted in said barrel for longitudinal movement therein, said master plunger assembly comprising a master plunger having a diameter located in said first chamber and a plunger member extending through said first barrel end for allowing a user to apply pressure thereto;

e) a single slave plunger having a diameter substantially equal to the diameter of said master plunger located in said second chamber of said barrel between said master plunger assembly and said second barrel end for longitudinal movement therein and to define a single therapeutic fluid chamber extending longitudinally from said slave plunger to said second barrel end, and to define a single pneumatic chamber containing said non-therapeutic compressible gas extending longitudinally from said slave plunger to said master plunger assembly, said slave plunger further serving to both isolate the therapeutic fluid and non-therapeutic compressible gas from each other and further serve to prevent the non-therapeutic compressible gas from being dispensed out of the syringe;

wherein only two plungers are within said barrel, and fluid cannot transfer through either of the two plungers; and

wherein, when said therapeutic fluid chamber contains a therapeutic fluid to be dispensed from said syringe, a user applying selective pressure to said plunger member will cause said master plunger assembly to slide towards said slave plunger and compress said non-therapeutic compressible gas against said slave plunger, said slave plunger will as a result of said pressure slide towards said second barrel end as said gas decompresses and apply pressure against said therapeutic fluid as a result thereof, and said therapeutic fluid will be dispensed out of the syringe via the means for allowing attachment of a needle assembly,

wherein said slave plunger is effective to prevent escape of said non-therapeutic compressible gas as the therapeutic fluid is dispensed out of the syringe via said second barrel end in accordance with said pressure applied to the plunger member.

2. The syringe of claim 1 in which the gas substantially comprises air.

3. The syringe of claim 1 in which the means for allowing attachment of a needle assembly comprises an opening in said second barrel end for coupling with a needle assembly.

4. The syringe of claim 1 in which the slave plunger and the master plunger each are comprised of a rubber disc having at least one ridge for making substantial contact with the barrel, said ridge being suitable for sliding engagement with said barrel when pressure is applied thereto.

5. The syringe of claim 1 wherein said plunger member comprises a thumb engagement means at an end opposite the master plunger, said thumb engagement means allowing a user to pull said plunger member away form said syringe and cause a negative pressure on said master plunger.

6. A syringe comprising:

a) a hollow barrel comprising a first barrel end and a second barrel end, said first barrel end being open and said second barrel end comprising means for allowing attachment of a needle assembly, said barrel having a first chamber and a second chamber of substantially equal diameters;

b) a master plunger assembly mounted in said barrel for longitudinal movement therein, said master plunger assembly comprising a master plunger having a diameter located in said first chamber and a plunger member extending through said first barrel end for allowing a user to apply pressure thereto;

c) a single slave plunger having a diameter substantially equal to the diameter of said master plunger located in said second chamber of said barrel between said master plunger assembly and said second barrel end for longitudinal movement therein and to define a single therapeutic fluid chamber extending longitudinally from said slave plunger to said second barrel end, and to define a single pneumatic chamber containing said non-therapeutic compressible gas extending longitudinally from said slave plunger to said master plunger assembly, said slave plunger thereby isolating the therapeutic fluid and non-therapeutic compressible gas from each other,

said first chamber accommodating said non-therapeutic compressible gas therein,

said second chamber accommodating the therapeutic fluid therein,

wherein only two plungers are within said barrel, and fluid cannot transfer through either of the two plungers; and

wherein said slave plunger is effective to prevent escape of said non-therapeutic compressible gas as the therapeutic fluid is dispensed out of the syringe via said second barrel end in accordance with said pressure applied to the plunger member.

7. The syringe of claim 6 in which the gas substantially comprises air.

8. The syringe of claim 6 in which the means for allowing attachment of a needle assembly comprises an opening in said second barrel end for coupling with a needle assembly.

9. The syringe of claim 6 in which the slave plunger and the master plunger each are comprised of a rubber disc having at least one ridge for making substantial contact with the barrel, said ridge being suitable for sliding engagement with said barrel when pressure is applied thereto.

10. The syringe of claim 6 wherein said plunger member comprises a thumb engagement means at an end opposite the master plunger, said thumb engagement means allowing a user to pull said plunger member away form said syringe and cause a negative pressure on said master plunger.

11. A syringe, consisting essentially of:

a) a hollow barrel having a first barrel end and a second barrel end, said first barrel end being open and said second barrel end including means for allowing attachment of a needle assembly, said barrel having a first chamber and a second chamber of substantially equal diameters;

b) said first chamber accommodating a non-therapeutic compressible gas which is not to be dispensed out of said first chamber;

c) said second chamber accommodating a therapeutic fluid capable of being dispensed out of said second chamber;

d) a master plunger assembly mounted in said barrel for longitudinal movement therein, said master plunger assembly including a master plunger having a diameter located in said first chamber and a plunger member extending through said first barrel end for allowing a user to apply pressure thereto;

e) a slave plunger having a diameter substantially equal to the diameter of said master plunger located in said second chamber of said barrel between said master plunger assembly and said second barrel end for longitudinal movement therein and to define a therapeutic fluid chamber between said slave plunger and said second barrel end, and to define a pneumatic chamber containing said non-therapeutic compressible gas between said slave plunger and said master plunger assembly, said slave plunger further serving to both isolate the therapeutic fluid and non-therapeutic compressible gas from each other and further serve to prevent the non-therapeutic compressible gas from being dispensed out of the syringe;

wherein, when said therapeutic fluid chamber contains a therapeutic fluid to be dispensed from said syringe, a user applying selective pressure to said plunger member will cause said master plunger assembly to slide towards said slave plunger and compress said non-therapeutic compressible gas against said slave plunger, said slave plunger will as a result of said pressure slide towards said second barrel end as said gas decompresses and apply pressure against said therapeutic fluid as a result thereof, and said therapeutic fluid will be dispensed out of the syringe via the means for allowing attachment of a needle assembly,

wherein said slave plunger is effective to prevent escape of said non-therapeutic compressible gas as the therapeutic fluid is dispensed out of the syringe via said second barrel end in accordance with said pressure applied to the plunger member.

12. The syringe of claim 11 in which the gas substantially comprises air.

13. The syringe of claim 11 in which the means for allowing attachment of a needle assembly includes an opening in said second barrel end for coupling with a needle assembly.

14. The syringe of claim 11 in which the slave plunger and the master plunger each are comprised of a rubber disc having at least one ridge for making substantial contact with the barrel, said ridge being suitable for sliding engagement with said barrel when pressure is applied thereto.

15. The syringe of claim 11 wherein said plunger member has a thumb engagement means at an end opposite the master plunger, said thumb engagement means allowing a user to pull said plunger member away form said syringe and cause a negative pressure on said master plunger.

16. A syringe, consisting essentially of:

a) a hollow barrel having a first barrel end and a second barrel end, said first barrel end being open and said second barrel end including means for allowing attachment of a needle assembly, said barrel having a first chamber and a second chamber of substantially equal diameters;

b) a master plunger assembly mounted in said barrel for longitudinal movement therein, said master plunger assembly including a master plunger having a diameter located in said first chamber and a plunger member extending through said first barrel end for allowing a user to apply pressure thereto;

c) a slave plunger having a diameter substantially equal to the diameter of said master plunger located in said second chamber of said barrel between said master plunger assembly and said second barrel end for longitudinal movement therein and to define a therapeutic fluid chamber between said slave plunger and said second barrel end, and to define a pneumatic chamber containing said non-therapeutic compressible gas between said slave plunger and said master plunger assembly, said slave plunger thereby isolating the therapeutic fluid and non-therapeutic compressible gas from each other,

said first chamber accommodating said non-therapeutic compressible gas therein,

said second chamber accommodating the therapeutic fluid therein,

wherein said slave plunger is effective to prevent escape of said non-therapeutic compressible gas as the therapeutic fluid is dispensed out of the syringe via said second barrel end in accordance with said pressure applied to the plunger member.

17. The syringe of claim 16 in which the gas substantially comprises air.

18. The syringe of claim 16 in which the means for allowing attachment of a needle assembly includes an opening in said second barrel end for coupling with a needle assembly.

19. The syringe of claim 16 in which the slave plunger and the master plunger each are comprised of a rubber disc having at least one ridge for making substantial contact with the barrel, said ridge being suitable for sliding engagement with said barrel when pressure is applied thereto.

20. The syringe of claim 16 wherein said plunger member has a thumb engagement means at an end opposite the master plunger, said thumb engagement means allowing a user to pull said plunger member away form said syringe and cause a negative pressure on said master plunger.