Patent US4074715A successfully refreshed from Google Patents.
US4074715A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Syringe plunger
Assignee: Becton Dickinson and Co
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Filing: 1976-11-01
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Granted: 1978-02-21
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Expires: 1996-11-01
Abstract
Abstract The disclosure is of a novel syringe plunger characterized by a completely immobile piston head. The plunger is advantageously used in syringe assemblies and facilitates the so-called "micrometer" injection.
Inventors
- 👤 Kenneth E. Geiger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:41
CPC Classifications
A; A61; A61M; A61M5/00; A61M5/178; A61M5/31; A61M5/315; A61M5/31511; A61M5/31515; A61M5/31525; A61M5/31531
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
57 words
A plunger for a syringe assembly, which comprises; a handle; a piston interlock; a shank joining said handle to the piston interlock; said interlock including a bar extending distally from said shank; and a piston, completely enmeshing and enclosing said bar and making full contact with the interlock, whereby said piston is immovably mounted on said interlock.
Claim 2
Dependent Claim
57 words
A plunger for a syringe assembly, which comprises; a handle; a piston interlock; a shank joining said handle to the piston interlock; said interlock including a bar extending distally from said shank; and a piston, completely enmeshing and enclosing said bar and making full contact with the interlock, whereby said piston is immovably mounted on said interlock.
Claim 3
Dependent Claim
17 words
A plunger of claim 1 wherein said piston interlock is an integrally molded part of said shank.
Claim 4
Dependent Claim
56 words
A plunger of claim 1 wherein said interlock comprises a plurality of bars extending distally from said shank, said bars being joined together by a ring and spaced apart by intervening space, said piston completely enmeshing and enclosing said interlock and making full contact with the interlock, whereby said piston is immovably mounted on said interlock.
Claim 5
Dependent Claim
27 words
A plunger of claim 1 wherein said shank, handle and interlock are fabricated from a rigid polymeric resin and said piston is fabricated from a styrene-butadiene copolymer.
Claim 6
Dependent Claim
14 words
A plunger according to claim 4 wherein said copolymer is filled with a slip-agent.
Claim 7
Dependent Claim
97 words
A syringe assembly, which comprises; a syringe barrel; a plunger slidably mounted in said barrel, said plunger comprising; a handle; a piston interlock; a shank joining said handle to the piston interlock; said interlock comprising a plurality of bars extending distally from said shank, said bars being joined together by a ring and spaced apart by intervening space; and a piston, completely enmeshing and enclosing said interlock and making full contact with the interlock, whereby said piston is immovably mounted on said interlock and adapted to form a sliding seal with the inside walls of said barrel.
Claim 8
Dependent Claim
97 words
A syringe assembly, which comprises; a syringe barrel; a plunger slidably mounted in said barrel, said plunger comprising; a handle; a piston interlock; a shank joining said handle to the piston interlock; said interlock comprising a plurality of bars extending distally from said shank, said bars being joined together by a ring and spaced apart by intervening space; and a piston, completely enmeshing and enclosing said interlock and making full contact with the interlock, whereby said piston is immovably mounted on said interlock and adapted to form a sliding seal with the inside walls of said barrel.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-20 | 1981-08-22 | 1982-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-20 | 1985-08-22 | 1986-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-20 | 1989-08-22 | 1990-02-21 | $7700.00 | Window Closed / Lapsed |