US4030498A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Syringe
Assignee: Baxter International Inc
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Filing: 1976-07-22
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Granted: 1977-06-21
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Expires: 1996-07-22
Abstract
Abstract A contamination resistant syringe is provided in which two sealing rings are axially spaced from each other. The sealing rings are prevented from sweeping the same area and there is no communication between the chamber defined by the two sealing rings and the discharge area forward of the inner sealing ring. In this manner, contamination which might enter from the rear of the barrel will be prevented from contact with the inner ssealing ring.
Inventors
- 👤 Douglas L. Tompkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:49
CPC Classifications
A; A61; A61M; A61M5/00; A61M5/178; A61M5/31; A61M5/315; A61M5/31511; A61M5/31513; A61M2005/3117; A61M2005/3121
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
155 words
In a syringe comprising a barrel defining a bore and having a discharge portion, and a plunger extending into said bore and movable therewithin, the improvement comprising, in combination: inner sealing means carried by said plunger and movable axially within said bore in an area proximate to said discharge portion for substantially preventing leakage of medicament or other biologic fluid contained in the space forward of said inner sealing means adjacent said discharge portion; outer sealing means carried by said plunger, said outer sealing means being spaced axially from said inner sealing means and movable axially within said bore in an area behind the travel area of said inner sealing means; said plunger having an axial length within the bore of more than one-half of the functional length of the bore void of sealing rings; and means for preventing said outer sealing means from moving in the area in which said inner sealing means travels.
Claim 2
Dependent Claim
155 words
In a syringe comprising a barrel defining a bore and having a discharge portion, and a plunger extending into said bore and movable therewithin, the improvement comprising, in combination: inner sealing means carried by said plunger and movable axially within said bore in an area proximate to said discharge portion for substantially preventing leakage of medicament or other biologic fluid contained in the space forward of said inner sealing means adjacent said discharge portion; outer sealing means carried by said plunger, said outer sealing means being spaced axially from said inner sealing means and movable axially within said bore in an area behind the travel area of said inner sealing means; said plunger having an axial length within the bore of more than one-half of the functional length of the bore void of sealing rings; and means for preventing said outer sealing means from moving in the area in which said inner sealing means travels.
Claim 3
Dependent Claim
16 words
In a syringe as described in claim 1, said inner and outer sealing means including O-rings.
Claim 4
Dependent Claim
50 words
In a syringe as described in claim 1, said means for preventing said outer sealing means from moving in the area in which said inner sealing means travels comprising an infusion pump coupled to said syringe and having a limited stroke, whereby said plunger travel is limited by said stroke.
Claim 5
Dependent Claim
50 words
In a syringe as described in claim 1, said means for preventing said outer sealing means from moving in the area in which said inner sealing means travels comprising said inner and outer sealing means being axially spaced from each other more than one-half the functional length of said bore.
Claim 6
Dependent Claim
44 words
In a syringe as described in claim 1, said means for preventing said outer sealing means from moving in the area in which said inner sealing means travels comprising a detent carried by said barrel to limit movement of said plunger within said barrel.
Claim 7
Dependent Claim
24 words
In a syringe as described in claim 1, including a detent carried by said barrel to limit movement of said plunger within said barrel.
Claim 8
Dependent Claim
30 words
In a syringe as described in claim 6, wherein said detent comprises an annular ring having an inner diameter that is greater than the outer diameter of said sealing rings.
References Cited (Backward Citations)
DE67033C
Cited
FR325274A
Cited
US766121A
Cited
US786697A
Cited
US788059A
Cited
US1771219A
Cited
US2688325A
Cited
US2771880A
Cited
US2842127A
Cited
US2896621A
Cited
US2902035A
Cited
US3255752A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-20 | 1980-12-20 | 1981-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-20 | 1984-12-20 | 1985-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-20 | 1988-12-20 | 1989-06-21 | $7700.00 | Window Closed / Lapsed |