US4030701A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic vehicle jack
Assignee: Individual
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Filing: 1976-04-06
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Granted: 1977-06-21
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Expires: 1996-04-06
Abstract
Abstract A pneumatic vehicle jack comprises a jack cylinder with a body and a piston rod assembly movable relative to each other, two levers pivoted to said body or piston rod assembly, located on either side of the longitudinal axis of the jack cylinder and carrying vehicle and ground engaging shoes, and two struts pivotally mounted between said levers on the one hand and said piston rod assembly or cylinder body on the other hand. A cartridge of compressed gas can be removably connected to said jack cylinder for actuating the same. Actuation of the jack cylinder causes the pivot points of the levers and struts to be brought closer together, to move the shoes away from each other. At the beginning stage of the actuation movement, the lever system comprising the levers and struts reduces the force exerted by the jack, and at the end of the said movement it increases said force. Because the volume occupied by the gas contained in the cartridge increases during the actuation of the jack, the force exerted by the jack cylinder progressively decreases. Thus, the lever system compensates for this decreasing force and a substantially constant force is exerted by the vehicle jack over its whole stroke, and the raising movement of the vehicle is also progressive and constant.
Inventors
- 👤 Pierre Joseph Pingon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:25
CPC Classifications
B; B66; B66F; B66F3/00; B66F3/24; B66F3/245
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
144 words
A pneumatic vehicle jack comprising a pneumatic jack cylinder made of relatively movable parts and having a pressure chamber, a cartridge of compressed air having a limited volume, means for connecting the interior of said cartridge with said pressure chamber of said jack cylinder, whereby the force exerted by said jack cylinder is progressively reduced when the volume of said pressure chamber increases during the operation of said jack, and a lever system connected to said movable parts of said jack cylinder and acting between the ground and the vehicle to be lifted, said lever system comprising levers so disposed as to reduce the force exerted by the jack cylinder at the beginning stage of the jack operation and for multiplying said force during the last stage of the said operation, so that a substantially constant lifting force is provided by said vehicle jack.
Claim 2
Dependent Claim
144 words
A pneumatic vehicle jack comprising a pneumatic jack cylinder made of relatively movable parts and having a pressure chamber, a cartridge of compressed air having a limited volume, means for connecting the interior of said cartridge with said pressure chamber of said jack cylinder, whereby the force exerted by said jack cylinder is progressively reduced when the volume of said pressure chamber increases during the operation of said jack, and a lever system connected to said movable parts of said jack cylinder and acting between the ground and the vehicle to be lifted, said lever system comprising levers so disposed as to reduce the force exerted by the jack cylinder at the beginning stage of the jack operation and for multiplying said force during the last stage of the said operation, so that a substantially constant lifting force is provided by said vehicle jack.
Claim 3
Dependent Claim
168 words
A pneumatic vehicle jack comprising a jack cylinder having two relatively movable parts forming a body and a piston rod assembly for said jack cylinder, said piston rod assembly having a piston slidably mounted in said body and a piston rod extending outside said body, two levers pivoted at pivot points on said body, said levers being arranged on either side of the longitudinal axis of said jack cylinder, ground and vehicle engaging shoes on said levers, two struts pivoted at pivot points on said piston rod at its end opposite said piston on the one hand, and to each lever on the other hand, means on said piston on its side opposite said piston rod for removably fitting a cartridge of compressed gas, and means for connecting the interior of said gas cartridge with the interior of said jack cylinder so as to move said body and piston rod assembly relative to each other thereby to pivot said levers away from one another to actuate the jack.
Claim 4
Dependent Claim
168 words
A pneumatic vehicle jack comprising a jack cylinder having two relatively movable parts forming a body and a piston rod assembly for said jack cylinder, said piston rod assembly having a piston slidably mounted in said body and a piston rod extending outside said body, two levers pivoted at pivot points on said body, said levers being arranged on either side of the longitudinal axis of said jack cylinder, ground and vehicle engaging shoes on said levers, two struts pivoted at pivot points on said piston rod at its end opposite said piston on the one hand, and to each lever on the other hand, means on said piston on its side opposite said piston rod for removably fitting a cartridge of compressed gas, and means for connecting the interior of said gas cartridge with the interior of said jack cylinder so as to move said body and piston rod assembly relative to each other thereby to pivot said levers away from one another to actuate the jack.
Claim 5
Dependent Claim
57 words
A pneumatic vehicle jack according to claim 2, wherein said levers are substantially parallel to each other in the collapsed condition of the jack, said levers having a U-shaped cross-section with open sides directed toward each other and enclosing said jack cylinder and said struts in a box-like manner when said jack is in its closed condition.
Claim 6
Dependent Claim
40 words
A pneumatic vehicle jack according to claim 2, comprising a rectangular block member on said jack cylinder body, said levers being pivoted on said rectangular block member, and said struts being pivoted between said levers and said piston rod assembly.
Claim 7
Dependent Claim
56 words
A pneumatic vehicle jack according to claim 2, comprising a housing in said piston on its side opposite said piston rod, said cartridge of compressed gas being fittable within said housing, and passages in said piston between said housing and the interior of said jack cylinder for the operation of the jack through said compressed gas.
Claim 8
Dependent Claim
87 words
A pneumatic vehicle jack according to claim 2, comprising a tubular jack cylinder body projecting from said piston on the side opposite said piston rod and beyond said pivot points of said levers on said jack cylinder body, to provide a handle allowing the jack to be held when it is positioned under a vehicle to be lifted, and a housing in said piston on its side opposite said piston rod for receiving said cartridge of compressed gas, said tubular jack cylinder body surrounding said piston housing.
Claim 9
Dependent Claim
131 words
A pneumatic vehicle jack according to claim 2, comprising a housing in said piston on its side opposite said piston rod, said cartridge of compressed gas being fittable within said housing, passages in said piston between said housing and the interior of said jack cylinder for the operation of the jack through said compressed gas, there being a threaded portion on said piston rod at its end opposite said piston, a ring freely slidable on said threaded portion of said piston rod, said levers being pivoted on said piston cylinder, and said struts being pivotally mounted between said levers and said slidable ring, and an abutment nut screwed on said threaded portion of said piston rod for abutting and adjusting said slidable ring and the starting position of said vehicle jack.
Claim 10
Dependent Claim
171 words
A pneumatic vehicle jack comprising a jack cylinder having two relatively movable parts forming a body and a piston rod assembly for said jack cylinder, said piston rod assembly having a piston slidably mounted in said body and a piston rod extending outside said body and having a free end, two levers pivoted at pivot points at said free end of said piston rod, said levers being arranged on either side of the longitudinal axis of said jack cylinder, ground and vehicle engaging shoes on said levers, two struts pivoted at pivot points on said cylinder body on the one hand and to each lever on the other hand, means at the free end of said piston rod for removably fitting a cartridge of said compressed gas, and means for connecting the interior of said gas cartridge with the interior of said jack cylinder so as to move said body and piston rod assembly relative to each other thereby to pivot said levers away from one another to actuate the jack.
Claim 11
Dependent Claim
171 words
A pneumatic vehicle jack comprising a jack cylinder having two relatively movable parts forming a body and a piston rod assembly for said jack cylinder, said piston rod assembly having a piston slidably mounted in said body and a piston rod extending outside said body and having a free end, two levers pivoted at pivot points at said free end of said piston rod, said levers being arranged on either side of the longitudinal axis of said jack cylinder, ground and vehicle engaging shoes on said levers, two struts pivoted at pivot points on said cylinder body on the one hand and to each lever on the other hand, means at the free end of said piston rod for removably fitting a cartridge of said compressed gas, and means for connecting the interior of said gas cartridge with the interior of said jack cylinder so as to move said body and piston rod assembly relative to each other thereby to pivot said levers away from one another to actuate the jack.
Claim 12
Dependent Claim
36 words
A pneumatic vehicle jack according to claim 8, comprising a longitudinal passage in said piston rod for connecting the interior of said compressed gas cartridge with the interior of said jack cylinder for operating the jack.
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) | 1980-06-20 | 1980-12-20 | 1981-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-20 | 1984-12-20 | 1985-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-20 | 1988-12-20 | 1989-06-21 | $7700.00 | Window Closed / Lapsed |