Patent US3667631A successfully refreshed from Google Patents.
US3667631A
Expired / Lapsed
US
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Hydraulic utility lift for trucks
Assignee: Individual
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Filing: 1971-01-22
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Granted: 1972-06-06
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Expires: 1991-01-22
Abstract
Abstract A hydraulic utility lift for pick-up trucks and other vehicles consisting of a frame adapted to be mounted under the rear portion of the truck bed and carrying a lift arm operable to lift a load disposed rearwardly of said truck as said arm is pivoted from a downwardly and rearwardly inclined position to a substantially horizontal position, a hydraulic ram for pivoting said arm, and a linkage operatively connecting said ram to said arm, said linkage having a novel arrangement whereby it both converts horizontal movements of said ram to vertical movement lifting said arm, whereby said ram may be elevated to preserve better ground clearance for said lift, and also provides a more uniform power ratio for said ram, permitting economies in the design of said ram.
Inventors
- 👤 Jerald W Bishop
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:45
CPC Classifications
B; B60; B60P; B60P3/00; B60P3/12; B60P3/125
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
179 words
A hydraulic utility lift for trucks comprising: a. a lift frame adapted to be affixed to the truck beneath the rearward portion of the truck bed, b. a lift arm pivoted to said frame on a horizontal transverse axis for movement from a downwardly and rearwardly inclined lowered position to a generally horizontal rearwardly extending raised position, c. a hydraulic ram extending longitudinally of said frame and pivoted at its forward end to said frame on a horizontal transverse axis spaced forwardly from the pivotal axis of said lift arm, d. guide means carried fixedly by said frame and limiting the rearward end of said ram to generally horizontal movement along a horizontal line spaced below the pivotal axis of said lift arm, e. a link pivoted at its forward end to the rearward end of said ram and at its rearward end to said lift arm, in rearwardly spaced relation from the pivotal axis of said lift arm, f. a tool support, and g. means for attaching said tool support to the rearward end of said lift arm.
Claim 2
Dependent Claim
179 words
A hydraulic utility lift for trucks comprising: a. a lift frame adapted to be affixed to the truck beneath the rearward portion of the truck bed, b. a lift arm pivoted to said frame on a horizontal transverse axis for movement from a downwardly and rearwardly inclined lowered position to a generally horizontal rearwardly extending raised position, c. a hydraulic ram extending longitudinally of said frame and pivoted at its forward end to said frame on a horizontal transverse axis spaced forwardly from the pivotal axis of said lift arm, d. guide means carried fixedly by said frame and limiting the rearward end of said ram to generally horizontal movement along a horizontal line spaced below the pivotal axis of said lift arm, e. a link pivoted at its forward end to the rearward end of said ram and at its rearward end to said lift arm, in rearwardly spaced relation from the pivotal axis of said lift arm, f. a tool support, and g. means for attaching said tool support to the rearward end of said lift arm.
Claim 3
Dependent Claim
58 words
The structure as recited in claim 1 wherein the vertical spacing between said arm pivot and the rearward end of said ram is substantially less than the longitudinal length of saidram, and wherein the forward end of said ram is pivoted to said frame at a point at least as high as the rearward end of said ram.
Claim 4
Dependent Claim
34 words
The structure as recited in claim 1 wherein the length of said link is greater than the vertical spacing between the rearward end of said ram and the pivotal axis of said lift arm.
Claim 5
Dependent Claim
75 words
The structure as recited in claim 1 wherein said guide means is operable to cause the rearward end of said hydraulic ram to move gradually farther away from the pivotal axis of said lift arm as said lift arm is elevated, whereby the angle of said link to said lift arm is gradually increased as said lift arm is raised, and the mechanical advantage of said link relative to said lift arm consequently gradually increased.
Claim 6
Dependent Claim
37 words
The structure as recited in claim 1 with the addition of a manually operable latch carried by said frame and operable to engage and secure said lift arm in its raised position independently of said hydraulic ram.
Claim 7
Dependent Claim
63 words
The structure as recited in claim 1 wherein said lift arm extends rearwardly to a position generally flush with the rearward end of the bed of said truck, wherein said tool support extends upwardly behind said truck bed when said lift arm is raised, and wherein said attaching means for said tool support is readily detachable to permit dismounting of said tool support.
Claim 8
Dependent Claim
131 words
The structure as recited in claim 6 whereIn said attaching means comprises: a. a pin fixed in said tool support and engageable freely and pivotally in a notch formed therefor in said lift arm when said tool support is angled on said pin away from its normal position relative to said lift arm, b. a tongue member carried fixedly by said tool support and operable to engage said lift arm to prevent disengagement of said pin from said notch when said tool support is pivoted on said pin to its normal position relative to said lift arm, and c. a gravity-actuated latch member carried by said lift arm and operable to engage and secure said tongue in its normal position relative to said lift arm, said latch member being manually releaseable.
Claim 9
Dependent Claim
74 words
The structure as recited in claim 1 wherein said tool support comprises: a. a frame extending upwardly and rearwardly from the rearward end of said lift arm when said arm is raised, b. a sleeve affixed to the rearward end of said frame and disposed vertically when said lift arm is in its raised position, c. a spindle disposed coaxially and rotatably in said sleeve, and d. a load-supporting tool carried by said spindle.
References Cited (Backward Citations)
US2625279A
Cited
US2715470A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |