Spring-actuated infusion syringe
First Claim
1. A spring-actuated syringe, comprising:
- a housing having an open distal end and a proximal end terminated by a proximal end wall;
a piston disposed in the housing for axial translation therein;
a tether connecting the piston to the proximal end of the housing;
a spring disposed longitudinally in the housing between the piston and the proximal end wall of the housing so as to bias the piston toward the distal end of the housing;
a barrel for the containment of a liquid medicament, the barrel having a distal end portion having a fluid flow passage therethrough and an open proximal end, the proximal end of the barrel being axially insertable in the housing through the open distal end of the housing, whereby the piston is received in the barrel through the proximal end of the barrel when the barrel is inserted into the housing;
a plunger disposed in the barrel for axial translation therein, the plunger being engaged by the piston when the piston is received in the barrel; and
retention means, operable between the barrel and the housing, for retaining the barrel at a selected axial position in the housing when the barrel is inserted axially into the housing.
3 Assignments
0 Petitions
Accused Products
Abstract
A spring-actuated infusion syringe includes a housing having an open distal end, with a spring-loaded piston disposed for axial translation in the housing. The piston is biased toward the distal end of the housing. The syringe also includes a barrel for containing a liquid medicament, the barrel having a distal end having a fluid passage therethrough and an open proximal end. A plunger is disposed in the barrel for axial translation therein. The proximal end of the barrel is axially insertable into the distal end of the housing, whereby the piston enters the proximal end of the barrel and engages the plunger. In use, the barrel is filled with a medicament through the fluid flow passage, and the flow of medicament from the syringe is obstructed. The proximal end of the barrel is inserted into the distal end of the housing, whereby the piston enters the proximal end of the barrel. The plunger, immobilized by the hydrostatic pressure of the liquid in the barrel, pushes the piston proximally against its biasing force. An engagement between an annular barrel flange and an internal housing thread retains the barrel at the desired axial position within the housing. To deliver the liquid from the syringe, the obstruction is removed. The hydrostatic pressure in the barrel being relieved, the biasing force of the piston pushes the plunger distally into the barrel, displacing the liquid therefrom through the fluid flow passage.
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Citations
16 Claims
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1. A spring-actuated syringe, comprising:
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a housing having an open distal end and a proximal end terminated by a proximal end wall; a piston disposed in the housing for axial translation therein; a tether connecting the piston to the proximal end of the housing; a spring disposed longitudinally in the housing between the piston and the proximal end wall of the housing so as to bias the piston toward the distal end of the housing; a barrel for the containment of a liquid medicament, the barrel having a distal end portion having a fluid flow passage therethrough and an open proximal end, the proximal end of the barrel being axially insertable in the housing through the open distal end of the housing, whereby the piston is received in the barrel through the proximal end of the barrel when the barrel is inserted into the housing; a plunger disposed in the barrel for axial translation therein, the plunger being engaged by the piston when the piston is received in the barrel; and retention means, operable between the barrel and the housing, for retaining the barrel at a selected axial position in the housing when the barrel is inserted axially into the housing. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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9. A spring-actuated syringe, comprising:
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a housing having an open distal end and a proximal end terminated by a proximal end wall; a spring-biased piston disposed in the housing for axial translation therein, the piston being biased toward the distal end of the housing; a filamentous tether connecting the piston to the proximal end wall of the housing; a barrel for the containment of a liquid medicament, the barrel having a distal end with a fluid flow passage therethrough and an open proximal end, the proximal end of the barrel being axially insertable in the housing trough the open distal end of the housing, whereby the piston is received in the barrel through the proximal end of the barrel when the barrel is inserted into the housing; a plunger disposed in the barrel for axial translation therein, the plunger being engaged by the piston when the piston is received in the barrel; and retention means, operable between the barel and the housing, for retaining the barrel at a selected axial position in the housing when the barrel is inserted axially into the housing. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
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Specification