Pre-filled syringe having a plunger, plunger insert and plunger rod
First Claim
Patent Images
1. A syringe designed to be pre-filled and stored ready for injection comprising:
- (a) a barrel having an inner surface defining a cylindrical chamber for retaining an injectable fluid therein;
a distal end terminating in a tapered tip to which an injection needle can be attached; and
a proximal end for receiving a plunger;
(b) a cup-shaped plunger slideably mounted in said barrel and positioned close to the proximal end of the barrel to provide a seal with the inner surface of the barrel, said plunger comprising;
(1) a distal convex face which is to interface with the injectable fluid contained in the barrel;
(2) a proximal face;
(3) an outside wall contiguous with the distal convex face having thereon;
distal ring, proximal ring and center ring extending radially outwardly and forming a slideable seal with the inner surface of the barrel;
(4) an inside wall;
(5) a bottom rim which together with the inside wall defines a cavity to receive a plunger insert;
(c) a rigid plunger insert having distal end and proximal end positioned within said cavity comprising;
an inside wall having female threads thereon to receive and engage male threads on a plunger rod;
a flange located at the proximal end having a diameter larger than the diameter of the bottom rim of the plunger so that said plunger insert is securely held within said cavity; and
(d) a plunger rod having distal and proximal ends, for engaging the plunger comprising;
(1) a shoulder portion at the distal end of the plunger rod to contact bottom rim of the plunger when plunger rod is inserted in the plunger to limit elongation of the plunger;
(2) a neck portion, contiguous with the plunger rod tip, having male threads thereon to engage female threads of plunger insert; and
(3) a plunger rod tip, located at the distal end of the plunger rod projecting in the direction of the plunger, the diameter of which is substantially smaller than the diameter of the plunger, and is designed to contact the proximal inside face of the plunger at the center portion thereof.
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0 Petitions
Accused Products
Abstract
Disclosed are pre-filled syringes equipped with an improved plunger having a plunge insert and a plunger rod, characterized by a leak-proof seal and easy sliding property.
77 Citations
18 Claims
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1. A syringe designed to be pre-filled and stored ready for injection comprising:
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(a) a barrel having an inner surface defining a cylindrical chamber for retaining an injectable fluid therein;
a distal end terminating in a tapered tip to which an injection needle can be attached; and
a proximal end for receiving a plunger;(b) a cup-shaped plunger slideably mounted in said barrel and positioned close to the proximal end of the barrel to provide a seal with the inner surface of the barrel, said plunger comprising; (1) a distal convex face which is to interface with the injectable fluid contained in the barrel; (2) a proximal face; (3) an outside wall contiguous with the distal convex face having thereon;
distal ring, proximal ring and center ring extending radially outwardly and forming a slideable seal with the inner surface of the barrel;(4) an inside wall; (5) a bottom rim which together with the inside wall defines a cavity to receive a plunger insert; (c) a rigid plunger insert having distal end and proximal end positioned within said cavity comprising;
an inside wall having female threads thereon to receive and engage male threads on a plunger rod;
a flange located at the proximal end having a diameter larger than the diameter of the bottom rim of the plunger so that said plunger insert is securely held within said cavity; and(d) a plunger rod having distal and proximal ends, for engaging the plunger comprising; (1) a shoulder portion at the distal end of the plunger rod to contact bottom rim of the plunger when plunger rod is inserted in the plunger to limit elongation of the plunger; (2) a neck portion, contiguous with the plunger rod tip, having male threads thereon to engage female threads of plunger insert; and (3) a plunger rod tip, located at the distal end of the plunger rod projecting in the direction of the plunger, the diameter of which is substantially smaller than the diameter of the plunger, and is designed to contact the proximal inside face of the plunger at the center portion thereof. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A method of delivering a liquid medium into a patient from a pre-filled syringe, said syringe comprising:
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(a) a barrel having an inner surface defining a cylindrical chamber for retaining an injectable fluid therein;
a distal end terminating in a tapered tip to which an injection needle can be attached; and
a proximal end for receiving a plunger;(b) a cup-shaped plunger slideably mounted in said barrel and positioned close to the proximal end of the barrel to provide a seal with the inner surface of the barrel, said plunger comprising; (1) a distal convex face which is to interface with the injectable fluid contained in the barrel; (2) a proximal face; (3) an outside wall contiguous with the distal convex face having thereon;
distal ring, proximal ring and center ring extending radially outwardly and forming a slideable seal with the inner surface of the barrel;(4) an inside wall; (5) a bottom rim which together with the inside wall defines a cavity to receive a plunger insert; (c) a rigid plunger insert having distal end and proximal end positioned within said cavity comprising;
an inside wall having female threads thereon to receive and engage male threads on a plunger rod;
a flange located at the proximal end having a diameter larger than the diameter of the bottom rim of the plunger so that said plunger insert is securely held within said cavity; and(d) a plunger rod having distal and proximal ends, for engaging the plunger comprising; (1) a shoulder portion at the distal end of the plunger rod to contact bottom rim of the plunger when plunger rod is inserted in the plunger to limit elongation of the plunger; (2) a neck portion, contiguous with the plunger rod tip, having male threads thereon to engage female threads of plunger insert; and (3) a plunger rod tip, located at the distal end of the plunger rod projecting in the direction of the plunger, the diameter of which is substantially smaller than the diameter of the plunger, and is designed to contact the proximal inside face of the plunger at the center portion thereof, said method comprising the steps of; (i) engaging a hypodermic needle with the tapered tip of said barrel; (ii) threading the plunger rod into the plunger; (iii) gaining entry into the desired injection site on the patient; (iv) exerting a slight pressure on the plunger rod to expel head gas from the barrel; (v) releasing the pressure applied on the plunger rod to create vacuum in the syringe and drawing a small amount of body fluid from the patient and into the distal end of the barrel; and (vi) exerting pressure on the plunger rod to move the plunger toward the distal end of the barrel thereby delivering the liquid medium into the patient. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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Specification