Multi-Chamber Syringe Having a Gas Separator

Abstract

A syringe is partitioned into at least proximal and distal chambers to provide a multi-chamber, sequentially dispensing syringe apparatus. The syringe includes a gas separator that prevents gas from exiting a chamber with delivered fluid.

1 . A multi-chamber syringe apparatus for sequentially dispensing medical fluids, said apparatus comprising:
 a syringe barrel which is concentrically disposed about an elongated medial axis, said barrel comprising an open proximal end and a distal end having a closed interior surface about an orifice through which fluid is transferred, said surface having a substantially concave shape;   a plunger and plunger stopper combination disposed to be displaced within said barrel for dislocating fluid thereby; and   a valve assembly disposed within said barrel between said plunger stopper and said distal end to provide a proximal chamber between the valve assembly and plunger stopper and a distal chamber between the valve assembly and said interior surface;   said valve assembly comprising:
 a valved stopper comprising a distal face and a hollow, grooved, cylindrical interior which opens proximally toward said plunger stopper and which communicates with said plunger stopper via fluid within the barrel, therebetween, to be displaced as the plunger stopper is displaced; 
 said valved stopper further comprising an operable, normally closed valve, which permits displacement of fluid therethrough only when open, and a pliable material whereby said distal face cooperatively conforms to the shape of the interior surface when forced thereupon; and 
 a valve actuator comprising features which are complimentary to grooves of the interior of the valved stopper whereby the actuator is securely affixed to the valved stopper and is displaced as the valved stopper is displaced; 
 said actuator further comprising structure for sensing impact between said distal face and said interior surface and, upon sensing the impact, reactively causes said valve to open. 
   
   
   
       2 . Apparatus according to  claim 1  wherein said actuator comprises a medially disposed elongated body which comprises a hollow opening which communicates with said valve. 
   
   
       3 . Apparatus according to  claim 2  wherein said actuator comprises at least one stabilizing element, affixed to said body which acts upon the valved stopper to resist canting of the valved stopper within the barrel to thereby assure stability of the valved stopper during forcible displacement by the plunger and plunger stopper combination. 
   
   
       4 . Apparatus according to  claim 3  wherein said at least one stabilizing element comprises a circular disk sized and shaped to provide support within the hollow of the valved stopper. 
   
   
       5 . Apparatus according to  claim 2  wherein said valve comprises a slit disposed through the distal face of said valved stopper. 
   
   
       6 . Apparatus according to  claim 5  wherein said stopper comprises a size and shape relative to said hollow syringe barrel which maintains said slit in a normally closed state unless acted upon by a valve opening mechanism of said impact sensing structure. 
   
   
       7 . Apparatus according to  claim 5  wherein said impact sensing structure comprises an arm which comprises a hinged connection to said body, said arm having a distally extending appendage which communicates with said inner surface through said distal face upon impact between the distal face and inner surface articulates to open said slit. 
   
   
       8 . Apparatus according to  claim 7  wherein said arm further comprises an outwardly extending part which is in contact with the hollow cylindrical interior of said stopper and which articulates as said arm articulates. 
   
   
       9 . Apparatus according to  claim 8  wherein said arm and said part couple comprise sufficient length away from said hinged connection to compressively act to forcibly maintain said slit closed prior to impact between said closed face and the inner surface. 
   
   
       10 . A multi-chamber syringe apparatus for sequentially dispensing medical fluids, said apparatus comprising:
 a syringe barrel having an internal surface which is concentrically disposed about an elongated medial axis, said barrel surface comprising an open proximal end and a distal end having a closed interior about an orifice through which fluid is transferred;   a stem and plunger combination disposed to be displaced within said barrel by application of a directional force against said stem for dislocating fluid thereby; and a valve assembly which, when disposed within said barrel between said plunger stopper and said distal end, provides a proximal chamber between the valve assembly and plunger stopper and a distal chamber between the valve assembly and said closed interior surface;   said valve assembly comprising:
 a valved stopper comprising a normally closed, medially disposed valve in a distal face of the stopper and a hollow, grooved, cylindrical interior which opens proximally toward said plunger and which communicates with said plunger stopper via fluid, within the barrel, said valved stopper being distally displaced toward said distal end within said barrel when acted upon by a force directionally applied toward said distal end which produces a first differential pressure and being proximally displaced away from said distal end when acted upon by an oppositely directed force of a second differential pressure; and 
 said valved stopper further comprising structure which only opens said valve to permit fluid flow there through when said stopper is acted upon by force of a third differential pressure which is in the same direction as force from the first differential pressure, the magnitude of the third differential pressure being greater than the first differential pressure. 
   
   
   
       11 . A multi-chamber syringe apparatus according to  claim 10  wherein said valved stopper comprises a bi-stable valve. 
   
   
       12 . A multi-chamber syringe apparatus according to  claim 10  comprises a slit valve comprising a medially disposed slit valve. 
   
   
       13 . A multi-chamber syringe apparatus according to  claim 12  wherein said bi-stable valve comprises a non-planar structure. 
   
   
       14 . A multi-chamber syringe apparatus according to  claim 13  wherein said non-planar valve comprises structure which defines operation of said valve to be bi-stable such that, once opened, said valve remains open. 
   
   
       15 . A multi-chamber syringe apparatus according to  claim 14  wherein said valved stopper further comprises a hinge disposed about said valve structure which articulates about said valve structure to permit the valve to be displaced to an open state when acted upon by force of said third differential pressure and to retain the valve in the open state, once opened. 
   
   
       16 . A multi-chamber syringe apparatus according to  claim 14  wherein said non-planar valve structure comprises a hemispherical dome shape. 
   
   
       17 . A multi-chamber syringe apparatus according to  claim 16  wherein said valved stopper further comprises a proximally disposed annular groove disposed to communicate through a wide proximal opening. 
   
   
       18 . A multi-chamber syringe apparatus according to  claim 10  wherein said valved stopper comprises material from which a syringe stopper is made. 
   
   
       19 . A multi-chamber syringe apparatus according to  claim 10  wherein the stem and plunger combination includes a catch that inhibits the plunger from contacting the valve assembly.