US3901356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lift mechanism
Assignee: Bear Manufacturing Corp
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Filing: 1972-03-15
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Granted: 1975-08-26
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Expires: 1992-03-15
Abstract
Abstract A scissors-type lift mechanism employs a reciprocating cam wedge adapted to engage cam follower rollers mounted on collapsed, transversely arranged scissor arms movable in the vertical plane. Movement of the cam in one direction forces the arms apart into a lifting movement as the rollers follow engaged cam surfaces. Movement of the cam in an opposite direction allows the scissor arms to collapse. In a modified construction, slotted toggle links pivotally connected to the cam engage pins on the scissor arms to effect an additional arm-spreading or lifting action after an initial spreading action effected by the cam.
Inventors
- 👤 Louis L Butler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:43
CPC Classifications
B; B66; B66F; B66F7/00; B66F7/06; B66F7/08; B66F7/065
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
152 words
In a vehicle lifting rack the combination comprising a vehicle supporting runway, a collapsible scissors type lifting mechanism supportably engaging undersurface portions of said runway, said mechanism comprising transversely arranged, pivotally connected scissor arms movable in the vertical plane and assuming a substantially horizontal side by side relationship when in the collapsed condition, cam follower means disposed on each of said scissor arms whereby each arm follower means is arranged in vertically aligned adjacent relationship with every other cam follower means when said scissor arms are in the collapsed condition, cam means pivotally supported at the pivotal connection of said arms and movable substantially horizontally between said cam follower means, said cam means being adapted to force said cam follower means apart and thereby force said scissor arms to move about their pivotal connection so as to raise their upper ends; the upper ends of said scissor arms supportably engaging said runway.
Claim 2
Dependent Claim
152 words
In a vehicle lifting rack the combination comprising a vehicle supporting runway, a collapsible scissors type lifting mechanism supportably engaging undersurface portions of said runway, said mechanism comprising transversely arranged, pivotally connected scissor arms movable in the vertical plane and assuming a substantially horizontal side by side relationship when in the collapsed condition, cam follower means disposed on each of said scissor arms whereby each arm follower means is arranged in vertically aligned adjacent relationship with every other cam follower means when said scissor arms are in the collapsed condition, cam means pivotally supported at the pivotal connection of said arms and movable substantially horizontally between said cam follower means, said cam means being adapted to force said cam follower means apart and thereby force said scissor arms to move about their pivotal connection so as to raise their upper ends; the upper ends of said scissor arms supportably engaging said runway.
Claim 3
Dependent Claim
35 words
The lifting rack of claim 1 in which said cam followers are rollers mounted on pins anchored in each of said scissor arms; said rollers being disposed adjacent the pivotal connection between said scissor arms.
Claim 4
Dependent Claim
41 words
The lifting rack of claim 2 in which said cam means comprises a wedge mounted on the end of a reciprocally movable piston rod extending from a cylinder, said cylinder being supportably mounted at the pivotal connection between said scissor arms.
Claim 5
Dependent Claim
91 words
The lifting rack of claim 2 in combination with slotted toggle links pivotally mounted on said cam means and having the slotted portions thereof slidably engageable with said pins while said cam means engages said cam followers; said slots being of such length that said cam means disengage from contact with said cam followers when said pins traverse the length of said slots whereafter cam movement forces said scissor arms to move about said pivotal connection by means of said toggle links as said toggle links pivot about said cam means.
Claim 6
Dependent Claim
32 words
An automotive lift rack comprising spaced lifting racks as described in claim 4 in combination with motive means for simultaneously raising and collapsing the scissor arms of each of said lifting racks.
Claim 7
Dependent Claim
77 words
The rack of claim 1 in which said cam means has a pointed end maintained between said cam follower means; in which movement of said scissor arms in the vertical plane causes vertical movement of said pivotal connection and corresponding pivotal movement of said cam means relative thereto; and in which said cam follower means are in vertical alignment and said cam means is disposed at substantially right angles thereto so as to be always substantially horizontal.
Claim 8
Dependent Claim
144 words
In a scissors type lift mechanism for imparting a vertical lift to a supported surface, the combination comprising transversely arranged scissor arms pivotally connected at their centers, having cam follower rollers mounted thereon which assume an adjacent relationship when said scissor arms are in a collapsed position, said rollers being in vertical alignment and disposed adjacent the pivot point of said arms when said scissor arms are in the collapsed condition, power driven cam means supported adjacent said cam followers adapted to spread said cam followers apart and simultaneously force said scissor arms to spread aparT about their pivot point, said cam means having inclined surfaces adapted to move substantially horizontally to so force said rollers into spaced relation, and said scissor arms and the supported surface being so related that spreading action of the scissor arms imparts vertical movement to the supported surface.
Claim 9
Dependent Claim
144 words
In a scissors type lift mechanism for imparting a vertical lift to a supported surface, the combination comprising transversely arranged scissor arms pivotally connected at their centers, having cam follower rollers mounted thereon which assume an adjacent relationship when said scissor arms are in a collapsed position, said rollers being in vertical alignment and disposed adjacent the pivot point of said arms when said scissor arms are in the collapsed condition, power driven cam means supported adjacent said cam followers adapted to spread said cam followers apart and simultaneously force said scissor arms to spread aparT about their pivot point, said cam means having inclined surfaces adapted to move substantially horizontally to so force said rollers into spaced relation, and said scissor arms and the supported surface being so related that spreading action of the scissor arms imparts vertical movement to the supported surface.
Claim 10
Dependent Claim
58 words
The lift mechanism of claim 7 in combination with slotted toggle links pivotally mounted on said cam means and slidably engaging pins on which said rollers are mounted during said cam-roller engagement by means of said slots; said links being adapted to force said scissor arms further apart after said wedge has initially spread apart said scissor arms.
Claim 11
Dependent Claim
77 words
The lift mechanism of claim 7 wherein said power means includes a hydraulic cylinder supportably mounted at the pivot connection between said scissor arms, a reciprocally movable piston rod extending from said cylinder toward said cam followers, and said cam means being mounted on said piston rod and normally disposed between said pivot connection and said cam followers for engaging and forcibly spreading said followers upon outward movement of said cam means relative to said pivot connection.
Claim 12
Dependent Claim
83 words
An automative lift rack comprising a pair of spaced generally parallel lift mechanisms each as described in claim 7; said power driven cam means of each of said lift mechanisms including a hydraulic cylinder and reciprocable piston rod unit disposed beneath the respective supporting surface, and each having a cam member mounted on said piston rod; the space between said mechanisms being unobstructed; and hydraulic motive means for simultaneously actuating said cylinders for simultaneously raising and collapsing the scissor arms of said mechanisms.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |