US3743248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic jack
Assignee: Individual
•
Filing: 1970-11-02
•
Granted: 1973-07-03
•
Expires: 1990-11-02
Abstract
Abstract A pneumatic jack comprising a telescopically extendable lifting axis which is enclosed by a flexible bellows, the lifting axis having five stages extendable telescopically with a first stage thereof being mounted on a rollable base plate, and at least the third and fourth stages of said lifting axis having a checking means for limiting movement of said latter stages into one another.
Inventors
- 👤 H Moor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:24
CPC Classifications
F; F15; F15B; F15B15/00; F15B15/08; F15B15/14; F15B15/16; B; B66; B66F; B66F3/00; B66F3/24; B66F3/25; B66F3/35; F15B15/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
140 words
A portable pneumatic jack comprising a telescopically extendible lifting assembly and a flexible bellows enclosing said lifting assembly, the lifting assembly having five stages telescopically engaged one into the other and adapted to slide thereinto, a rollable base plate for supporting said member, said base plate defining means for resting on a support surface during use and be rollable when not in use the first lower stage being fixed to the said plate, a groove provided around the periphery of at least the upper third and fourth stages, said groove being located below the outer upper edge, and a ring disposed in each of said grooves, wherein the ring is adapted to rest on the upper surface of the next lower stage before the said third and fourth stages reach their lowermost position relative to the respective next stages'' position.
Claim 2
Dependent Claim
140 words
A portable pneumatic jack comprising a telescopically extendible lifting assembly and a flexible bellows enclosing said lifting assembly, the lifting assembly having five stages telescopically engaged one into the other and adapted to slide thereinto, a rollable base plate for supporting said member, said base plate defining means for resting on a support surface during use and be rollable when not in use the first lower stage being fixed to the said plate, a groove provided around the periphery of at least the upper third and fourth stages, said groove being located below the outer upper edge, and a ring disposed in each of said grooves, wherein the ring is adapted to rest on the upper surface of the next lower stage before the said third and fourth stages reach their lowermost position relative to the respective next stages'' position.
Claim 3
Dependent Claim
69 words
A pneumatic jack as claimed in claim 1, wherein the four lower stages are constructed of steel tubing, while the uppermost stage consists of a pin, and the four lower stages are each provided with an internal upper projection which, when the stages are extended, is caused to come into contact with an internal lower projection of the next higher stage to limit outward relative movement of said stages.
Claim 4
Dependent Claim
52 words
A pneumatic jack as claimed in claim 1, wherein the checking means comprises a Seger ring attached to the upper end of the outer casing of the third and fourth stages and which, when the stages slide into each other, strike against the upper edges of the third and second stages respectively.
Claim 5
Dependent Claim
48 words
A pneumatic jack as claimed in any of claim 1 wherein two rollers are pivoted at one wide side of the base plate in such a manner that when the base plate is set on the ground the running surfaces of these rollers do not touch the ground.
Claim 6
Dependent Claim
31 words
A pneumatic jack as claimed in claim 4 wherein to the base plate is secured a guide handle which has securing means for the free end of an air supply hose.
Claim 7
Dependent Claim
39 words
A pneumatic jack as claimed in claim 5, wherein the other end of the air supply hose is attached to a flange member secured to the base plate, in which flange member there is additionally arranged a safety valve.
References Cited (Backward Citations)
US1711565A
Cited
US1917011A
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US2070960A
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US2803224A
Cited
US2805839A
Cited
US3298664A
Cited
US3279755A
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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) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |