US3830468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trailer jack
Assignee: Individual
•
Filing: 1973-06-11
•
Granted: 1974-08-20
•
Expires: 1993-06-11
Abstract
Abstract A jack comprising a lower upright tubular member closed at the lower end, an intermediate upright tubular member telescopically received in the lower member, the intermediate member being closed at the bottom, granular material within the annular area between the lower and intermediate member, the granular member falling to the lower end of the lower member as the intermediate member is withdrawn to thereby support the intermediate member in withdrawn position, an upper tubular member telescopically received in the intermediate member and granular material within the upper member and the lower portion of the intermediate member, the granular material falling to a lower portion of the intermediate member as the upper member is withdrawn to thereby support the upper member in the withdrawn position.
Inventors
- 👤 W Whitchurch
- 👤 I Willis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:54
CPC Classifications
B; B66; B66F; B66F3/00; B66F3/08; B66F3/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
172 words
A jack comprising: a lower upright tubular member closed at the lower end; an intermediate upright tubular member of external diameter less than the internal diameter of said lower member, the intermediate tubular member being telescopically received in said lower member, the intermediate member being closed at the bottom; granular material within the annular area between the lower and intermediate members, the granular material falling to the lower end of the lower member as said intermediate member is withdrawn to thereby support the intermediate member in such withdrawn position; an upper upright tubular member of external diameter less than the internal diameter of said intermediate member, the upper member being telescopically received in said intermediate member and being opened at the bottom and closed at the upper end thereof; and granular material within said upper member and the lower portion of said intermediate member, the granular material falling to the lower portion of said intermediate member as said upper member is withdrawn to thereby support the upper member in such withdrawn position.
Claim 2
Dependent Claim
172 words
A jack comprising: a lower upright tubular member closed at the lower end; an intermediate upright tubular member of external diameter less than the internal diameter of said lower member, the intermediate tubular member being telescopically received in said lower member, the intermediate member being closed at the bottom; granular material within the annular area between the lower and intermediate members, the granular material falling to the lower end of the lower member as said intermediate member is withdrawn to thereby support the intermediate member in such withdrawn position; an upper upright tubular member of external diameter less than the internal diameter of said intermediate member, the upper member being telescopically received in said intermediate member and being opened at the bottom and closed at the upper end thereof; and granular material within said upper member and the lower portion of said intermediate member, the granular material falling to the lower portion of said intermediate member as said upper member is withdrawn to thereby support the upper member in such withdrawn position.
Claim 3
Dependent Claim
59 words
A jack according to claim 1 including: a bushing closing the upper end of said upper member, the bushing having a threaded opening therein; and an externally threaded screw received in said threaded opening of said bushing, whereby the length of the jack may be adjusted by the rotation of said screw and said bushing relative to each other.
Claim 4
Dependent Claim
36 words
A jack according to claim 1 wherein said upright tubular member includes an enlarged internal diameter portion intermediate the upper and lower end thereof, the enlarged diameter portion serving as a reservoir of said granular material.
Claim 5
Dependent Claim
62 words
A jack according to claim 1 including: a first seal member closing the upper end of said lower tubular member, the first seal member having an opening therein slidably receiving said intermediate tubular member; and a second seal member closing the upper end of said intermediate tubular member, the second seal member having an opening therein slidably receiving said upper tubular member.
References Cited (Backward Citations)
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Cited
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US1895053A
Cited
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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) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |