US3556481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air-operated scissors-type jack
Assignee: McNeil Corp
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Filing: 1969-01-23
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Granted: 1971-01-19
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Expires: 1989-01-23
Abstract
Abstract A scissors-type jack for a vehicle lift comprises a base, a scissors linkage above the base and a platform on the scissors linkage adapted to be raised to various elevations by upward extension of the linkage from the base. The linkage is adapted to be so extended by air cylinder actuated follower rollers which have a wedging action between the links of the scissors linkage, the air cylinder being movable with the scissors pivot. An auxiliary locking mechanism is provided for locking the follower rollers in various platform-elevating positions thereof to prevent collapse of the jack under load in the event of failure of the air cylinder to hold the follower rollers in platformelevating position.
Inventors
- 👤 Carl H Mueller
- 👤 Jerome B Wegmann
- 👤 Clarence E Kitchen
- 👤 George Weitzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:01
CPC Classifications
B; B66; B66F; B66F3/00; B66F3/24; B66F3/247; B66F7/00; B66F7/06; B66F7/065; B66F7/08
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
137 words
A jack comprising a base, a scissors linkage extending upward from the base, a platform on the scissors linkage adapted to be raised to various elevations by upward extension of the linkage from the base, said linkage comprising scissors links pivotally interconnected intermediate their ends by a scissors pivot which moves upward on extension of the linkage and downward on retraction of the linkage, folloWer means between the links on one side of the pivot movable inward toward the pivot with a wedging action between the links for extending them to raise the platform to various elevations and movable outward away from the pivot for downward retraction of the linkage, and cylinder and piston means movable upward and downward with the scissors pivot and interconnected with the follower means for moving it inward to various platform-elevating positions.
Claim 2
Dependent Claim
137 words
A jack comprising a base, a scissors linkage extending upward from the base, a platform on the scissors linkage adapted to be raised to various elevations by upward extension of the linkage from the base, said linkage comprising scissors links pivotally interconnected intermediate their ends by a scissors pivot which moves upward on extension of the linkage and downward on retraction of the linkage, folloWer means between the links on one side of the pivot movable inward toward the pivot with a wedging action between the links for extending them to raise the platform to various elevations and movable outward away from the pivot for downward retraction of the linkage, and cylinder and piston means movable upward and downward with the scissors pivot and interconnected with the follower means for moving it inward to various platform-elevating positions.
Claim 3
Dependent Claim
69 words
A jack as set forth in claim 1 further having auxiliary means for locking the follower means against outward movement from any platform-elevating position thereof to prevent collapse of the jack under load in the event of failure of the cylinder and piston means to hold the follower means in platform-elevating position, said locking means being releasable to allow outward movement of the follower means for lowering the platform.
Claim 4
Dependent Claim
50 words
A jack as set forth in claim 2 wherein the cylinder and piston means comprises a cylinder movable with the pivot, a piston in the cylinder, and piston rod means movable with the piston and connected to the follower means, said locking means being interengageable with the piston rod means.
Claim 5
Dependent Claim
43 words
A jack as set forth in claim 2 wherein said locking means comprises a series of locking members successively movable from a retracted position to a locking position engageable by the piston rod means to lock the latter against movement in linkage-retracting direction.
Claim 6
Dependent Claim
23 words
A jack as set forth in claim 4 further comprising cylinder and piston means for moving said locking members to their retracted position.
Claim 7
Dependent Claim
85 words
A jack as set forth in claim 4 wherein said piston rod means comprises a first rod extending through one end of the cylinder to a connection with the follower means and a second rod extending through the other end of the cylinder having a shoulder facing said other end of the piston, and having means carrying said locking members at said other end of the cylinder, said locking members being successively movable behind said shoulder as the piston rod means moves in linkage-extending direction.
Claim 8
Dependent Claim
97 words
A jack as set forth in claim 6 wherein said second rod has an outer end extension of larger diameter than the second rod, each of said locking members comprising a plate located above the second rod disposed in a plane at right angles to the axis of the rod, said plates being arranged in face-to-face engagement, each plate being individually vertically slidable between a raised retracted position wherein its lower end engages said extension and a lowered locking position wherein one face thereof is engageable by the inner end of said extension acting as said shoulder.
Claim 9
Dependent Claim
26 words
A jack as set forth in claim 7 wherein each plate has a notch extending upward from its bottom edge adapted to receive said second rod.
Claim 10
Dependent Claim
18 words
A jack as set forth in claim 8 further comprising cylinder and piston means for raising said plates.
Claim 11
Dependent Claim
66 words
A jack as set forth in claim 9 wherein said cylinder and piston means for raising said plates comprises a cylinder mounted below said plates, a piston extending up out of said cylinder, and a pusher on the upper end of said piston having side members extending upward on opposite sides of said second rod and said extension engageable with the lower edges of said plates.
Claim 12
Dependent Claim
68 words
A jack as set forth in claim 1 wherein said cylinder and piston means comprises a cylinder having scissors pivots extending laterally outward from opposite sides thereof, and said scissors linkage comprises two pairs of scissors links, one pair being pivoted on the scissors pivot on one side of the cylinder, and the other pair being pivoted on the scissors pivot on the other side of the cylinder.
Claim 13
Dependent Claim
51 words
A jack as set forth in claim 11 wherein said cylinder has a piston therein and a rod extending from the piston through one end of the cylinder, said follower means comprising a crossbar on the outer end of said rod and follower rollers on the crossbar between the scissors links.
Claim 14
Dependent Claim
81 words
A jack as set forth in claiM 12 having auxiliary means mounted on the outside of the other end of the cylinder for locking the piston and follower rollers against outward movement from any platform-elevating position thereof to prevent collapse of the jack under load in the event of failure of the cylinder and piston means to hold the follower rollers in platform-elevating position, said locking means being releasable to allow outward movement of the follower rollers for lowering the platform.
Claim 15
Dependent Claim
152 words
A jack as set forth in claim 13 wherein said piston has a second piston rod extending through said other end of the cylinder having an outer end extension of larger diameter than said second rod providing a shoulder at the inner end of said extension facing said other end of the cylinder, said locking means comprising a housing on said other end of the cylinder, a plurality of locking plates arranged in a row above the piston rod axis in said housing with each plate in a plane at right angles to said axis, said plates being arranged in face-to-face engagement, each plate being individually vertically slidable between a raised retracted position wherein its lower end engages said extension and a lowered locking position wherein one face thereof is engageable by said shoulder, said extension extending through said housing and holding all said plates raised when the platform is fully lowered.
Claim 16
Dependent Claim
40 words
A jack as set forth in claim 14 wherein each plate has a notch extending upward from its bottom edge adapted to receive said second piston rod, the width of said notch being less than the diameter of said extension.
Claim 17
Dependent Claim
22 words
A jack as set forth in claim 15 further comprising cylinder and piston means carried by said housing for raising said plates.
Claim 18
Dependent Claim
66 words
A jack as set forth in claim 16 wherein said cylinder and piston means for raising said plates comprises a cylinder mounted below said plates, a piston extending up out of said cylinder, and a pusher on the upper end of said piston having side members extending upward on opposite sides of said second rod and said extension engageable with the lower edges of said plates.
Claim 19
Dependent Claim
60 words
A jack as set forth in claim 17 having a valve for controlling the supply and exhaust of air from the cylinder for the follower rollers and adapted to trap air in this cylinder, and a valve operable to supply air to the cylinder for raising the locking plates and adapted on release to bleed air from the latter cylinder.
References Cited (Backward Citations)
US2862689A
Cited
DE1175852B
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |