Patent US4770367A successfully refreshed from Google Patents.
US4770367A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic tape cassettes
Assignee: KOLLER INDUSTRIES Inc
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Filing: 1987-03-25
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Granted: 1988-09-13
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Expires: 2007-03-25
Abstract
Abstract A magnetic tape cassette has an improved reel spring, slack limiter and tape guide. The reel spring has a generally rectangular shape with first and second parallel edges extending substantially along its entire length. A flat, central base portion of the spring is bounded by a pair of transition portions which extend at an angle out of the plane of the base. A pair of outer end portions set at a sharper angle to the base complete the spring configuration. A polypropylene slack limiter applies a preloaded tension on the magnetic tape. The polypropylene eliminates the need for laminating a separate bearing material to the slack limiter. The tape guide has a semi-cylindrical, stainless steel insert attached to a plastic mounting core. The core is fastened to the cassette housing.
Inventors
- 👤 William M. Carroll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:11
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/04; G11B23/08; G11B23/087
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
138 words
In a magnetic tape cassette, a reel spring comprising an elongated strip of resilient material having first and second edges extending substantially throughout its length parallel to a longitudinal centerline, and the strip further including a flat, central base portion, a first pair of transverse crimps at the ends of the base portion defining transition sections of the strip extending at a first angle to the plane of the base portion, and a second pair of transverse crimps at the outer ends of the transition sections defining end portions of the strip extending at a second angle to the plane of the base portion, and means for mounting said reel spring to the cassette, said means being formed in said base portion and disposed upon the longitudinal centerline of said spring and spaced from the transverse centerline thereof.
Claim 2
Dependent Claim
138 words
In a magnetic tape cassette, a reel spring comprising an elongated strip of resilient material having first and second edges extending substantially throughout its length parallel to a longitudinal centerline, and the strip further including a flat, central base portion, a first pair of transverse crimps at the ends of the base portion defining transition sections of the strip extending at a first angle to the plane of the base portion, and a second pair of transverse crimps at the outer ends of the transition sections defining end portions of the strip extending at a second angle to the plane of the base portion, and means for mounting said reel spring to the cassette, said means being formed in said base portion and disposed upon the longitudinal centerline of said spring and spaced from the transverse centerline thereof.
Claim 3
Dependent Claim
15 words
The reel spring of claim 1 wherein the tips of the end portions are rounded.
Claim 4
Dependent Claim
13 words
The reel spring of claim 1 wherein the resilient material is stainless steel.
Claim 5
Dependent Claim
24 words
A reel spring as claimed in claim 1 wherein said means for mounting include separate means disposed on opposite sides of the transverse centerline.
Claim 6
Dependent Claim
20 words
A reel spring as claimed in claim 4 wherein said separate means for mounting are equidistant from said transverse centerline.
Claim 7
Dependent Claim
22 words
A reel spring as claimed in claim 5 herein said means for mounting includes a pair of apertures through said base portion.
Claim 8
Dependent Claim
13 words
A reel spring as claimed in claim 6 herein said apertures are circular.
Claim 9
Dependent Claim
85 words
In a magnetic tape cassette, a reel spring comprising an elongated strip of resilient material having first and second parallel edges extending substantially throughout its length with an uninterrupted surface therebetween, the strip having a central base portion and adjoining end portions extending out of the plane of the base portion, and means for mounting said reel spring to the cassette, said means being formed in said base portion and disposed upon the longitudinal centerline of said spring and spaced from the transverse centerline thereof.
Claim 10
Dependent Claim
85 words
In a magnetic tape cassette, a reel spring comprising an elongated strip of resilient material having first and second parallel edges extending substantially throughout its length with an uninterrupted surface therebetween, the strip having a central base portion and adjoining end portions extending out of the plane of the base portion, and means for mounting said reel spring to the cassette, said means being formed in said base portion and disposed upon the longitudinal centerline of said spring and spaced from the transverse centerline thereof.
Claim 11
Dependent Claim
15 words
The reel spring of claim 8 wherein the spring has an overall generally curved configuration.
Claim 12
Dependent Claim
15 words
The reel spring of claim 8 wherein the tips of the end portions are rounded.
Claim 13
Dependent Claim
13 words
The reel spring of claim 8 wherein the resilient material is stainless steel.
Claim 14
Dependent Claim
24 words
A reel spring as claimed in claim 8 wherein said means for mounting include separate means disposed on opposite sides of the transverse centerline.
Claim 15
Dependent Claim
20 words
A reel spring as claimed in claim 12 wherein said separate means for mounting are equidistant from said transverse centerline.
Claim 16
Dependent Claim
22 words
A reel spring as claimed in claim 13 wherein said means for mounting includes a pair of apertures through said base portion.
Claim 17
Dependent Claim
13 words
A reel spring as claimed in claim 14 wherein said apertures are circular.
Claim 18
Dependent Claim
99 words
A magnetic tape cassette reel spring comprising an elongated strip of resilient material having first and second parallel, exterior edges extending substantially throughout its length parallel to a longitudinal centerline, first and second tips at the ends of the strip connecting the first and second exterior edges, the strip defining a central base portion and adjoining end portions which extend out of the plane of the base portion and means for mounting said reel spring to a cassette formed in said base portion and disposed upon the longitudinal centerline of said stirp and spaced from the transverse centerline thereof.
Claim 19
Dependent Claim
99 words
A magnetic tape cassette reel spring comprising an elongated strip of resilient material having first and second parallel, exterior edges extending substantially throughout its length parallel to a longitudinal centerline, first and second tips at the ends of the strip connecting the first and second exterior edges, the strip defining a central base portion and adjoining end portions which extend out of the plane of the base portion and means for mounting said reel spring to a cassette formed in said base portion and disposed upon the longitudinal centerline of said stirp and spaced from the transverse centerline thereof.
Claim 20
Dependent Claim
24 words
The reel spring of claim 16 wherein the end portions are separated from the central base portion by a first pair of transverse crimps.
Claim 21
Dependent Claim
50 words
The reel spring of claim 17 wherein the end portion further comprises a second pair of transverse crimps defining a transition section extending at a first angle to the plane of the base portion and an end portion extending at a second angle to the plane of the base portion.
Claim 22
Dependent Claim
15 words
The reel spring of claim 16 wherein the tips of the end portions are rounded.
Claim 23
Dependent Claim
13 words
The reel spring of claim 16 wherein the resilient material is stainless steel.
Claim 24
Dependent Claim
23 words
A spring as claimed in claim 16 wherein said means for mounting include separate means disposed on opposite sides of the transverse centerline.
Claim 25
Dependent Claim
20 words
A reel spring as claimed in claim 21 wherein said separate means for mounting are equidistant from said transverse centerline.
Claim 26
Dependent Claim
22 words
A reel spring as claimed in claim 22 wherein said means for mounting includes a pair of apertures through said base portion.
Claim 27
Dependent Claim
15 words
A reel spring as claimed in claim 23 wherein said resilient material is stainless steel.
Claim 28
Dependent Claim
13 words
A reel spring as claimed in claim 23 wherein said apertures are circular.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |