Disposable syringe with automatic needle retraction
First Claim
1. A disposable syringe assembly, comprising:
- a barrel having a proximal end and a distal end and an internal central bore;
a tubular plunger having a closed proximal end, said plunger being telescopingly insertable within the proximal end of said central bore of said barrel and adapted for sealed, sliding reciprocating movement therewithin;
needle attachment means mounted around the inner wall of said barrel, said needle attachment means being adapted for receiving a hypodermic needle mountable therein and having a releasable hub portion adapted for movement within said central bore of said barrel when released;
a plunger distal seal member mounted on the distal end of said tubular plunger, said plunger distal seal member having a releasable hub portion adapted for sealed sliding movement within said tubular plunger when released, said plunger distal seal member closing and sealing the distal end of said plunger prior to release of said hub portion of said plunger distal seal member, the interior of said tubular plunger being relatively evacuated;
said releasable hub portions of said needle attachment means and said plunger distal seal member being releasable in sequence and lockingly engageable with one another upon application of a predetermined longitudinal axial force on said plunger, the distal end of said barrel having an opening therein exposing the distal faces of said releasable hub portions of said plunger distal seal member and said needle attachment means to the atmosphere;
said releasable hub portions of said needle attachment means and said plunger distal seal member being forced, when engaged with one another and released, into the relatively evacuated interior of said plunger by differential pressure between said evacuated interior and the atmosphere.
2 Assignments
0 Petitions
Accused Products
Abstract
A disposable medicinal syringe including a tubular plunger from which air has been evacuated and a seal member releasably attached on the distal end of the plunger. The plunger is slidingly and sealingly disposed in the barrel of the syringe. A luer lock assembly is mounted within the barrel and includes a releasable hub portion which is securely engageable with the releasable plunger seal member, the securely engaged members when released being actuated by ambient air pressure into retraction into the evacuated plunger. The luer lock assembly is adapted for receiving a hypodermic needle or other medical device. Following use of the syringe, longitudinal axial force is applied to the proximal end of the plunger, thereby detaching, in sequence, first and second annular thin-walled portions of the luer lock assembly to release the hub portion for movement within the barrel, securely mounting the plunger seal member into the luer lock hub, and detaching the plunger seal member from the plunger at an annular thin-walled portion. The combined luer lock hub/plunger seal member and attached needle or other medical device are then forced into the evacuated interior of the plunger, safely isolating the needle or other medical device inside the plunger.
190 Citations
12 Claims
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1. A disposable syringe assembly, comprising:
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a barrel having a proximal end and a distal end and an internal central bore; a tubular plunger having a closed proximal end, said plunger being telescopingly insertable within the proximal end of said central bore of said barrel and adapted for sealed, sliding reciprocating movement therewithin; needle attachment means mounted around the inner wall of said barrel, said needle attachment means being adapted for receiving a hypodermic needle mountable therein and having a releasable hub portion adapted for movement within said central bore of said barrel when released; a plunger distal seal member mounted on the distal end of said tubular plunger, said plunger distal seal member having a releasable hub portion adapted for sealed sliding movement within said tubular plunger when released, said plunger distal seal member closing and sealing the distal end of said plunger prior to release of said hub portion of said plunger distal seal member, the interior of said tubular plunger being relatively evacuated; said releasable hub portions of said needle attachment means and said plunger distal seal member being releasable in sequence and lockingly engageable with one another upon application of a predetermined longitudinal axial force on said plunger, the distal end of said barrel having an opening therein exposing the distal faces of said releasable hub portions of said plunger distal seal member and said needle attachment means to the atmosphere; said releasable hub portions of said needle attachment means and said plunger distal seal member being forced, when engaged with one another and released, into the relatively evacuated interior of said plunger by differential pressure between said evacuated interior and the atmosphere. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification