US4856776A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coil spring exerciser
Assignee: Individual
•
Filing: 1987-12-31
•
Granted: 1989-08-15
•
Expires: 2007-12-31
Abstract
Abstract A dyna-bender includes an internal coil spring; an external coil spring, coaxially surrounding the internal coil spring, having an intermediate portion spaced from the internal coil spring at a predetermined distance, and two opposite end portions having diameter-reduced turns for being sleeved tightly on the internal coil spring; and two hollow plastic grips each having an open inner end which is heat pressed to sleeve tightly on one of the end portions of the external coil spring.
Inventors
- 👤 Liu Ching-Liang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:11
CPC Classifications
A; A63; A63B; A63B21/00; A63B21/02; A63B21/045; A63B21/0004; A63B21/00043; A63B21/40; A63B21/4027; A63B21/4033; A63B21/4035; A63B21/023; A63B21/4041; A63B21/4043; A63B21/4047; A63B23/00; A63B23/035; A63B23/12
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
107 words
A coil spring exerciser an internal coil spring; an external coil spring, coaxially surrounding said internal coil spring, having an intermediate portion spaced from internal coil spring at a predetermined distance whereby said spacing reduces frictional contact between the springs during bending of the device, and two opposite end portions having diameter-reduced turns for being sleeved tightly on said internal coil spring whereby said sleeving fixes the ends of the internal spring relative to the ends of the external spring; and two hollow plastic grips each having an open end which is heat pressed to sleeve tightly on of said end portions of said external coil spring.
Claim 2
Dependent Claim
107 words
A coil spring exerciser an internal coil spring; an external coil spring, coaxially surrounding said internal coil spring, having an intermediate portion spaced from internal coil spring at a predetermined distance whereby said spacing reduces frictional contact between the springs during bending of the device, and two opposite end portions having diameter-reduced turns for being sleeved tightly on said internal coil spring whereby said sleeving fixes the ends of the internal spring relative to the ends of the external spring; and two hollow plastic grips each having an open end which is heat pressed to sleeve tightly on of said end portions of said external coil spring.
Claim 3
Dependent Claim
35 words
A coil spring exerciser as claimed in claim 1, wherein said internal and external coil springs are the same length so that said external coil spring surrounds said internal coil spring along their full length.
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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) | 1992-08-14 | 1993-02-13 | 1993-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-14 | 1997-02-13 | 1997-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-14 | 2001-02-13 | 2001-08-15 | $7700.00 | Window Closed / Lapsed |