US4000789A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable scaffold
Assignee: Individual
•
Filing: 1976-02-18
•
Granted: 1977-01-04
•
Expires: 1996-02-18
Abstract
Abstract An improved portable scaffold is the subject of the present invention. A base framework is provided with horizontally telescoping feet to accommodate free movement of the scaffold while still affording maximum stability during use. A telescoping tongue member likewise facilitates transportation but during use of the lifting device may be moved to an out of the way position substantially underlying the plane of the framework. Foldable upright standards are coupled with the framework at each end and mount platform supporting means for movement therealong. A platform member which substantially spans the distance between the upright standards is coupled with the platform supporting means at each end by a hangar bracket which accommodates 90° pivotal movement between the supporting means and the platform. Each bracket also extends away from the supporting means a distance at least equal to the width of one upright standard so as to accommodate folding of the standards one on top of the other.
Inventors
- 👤 Louis J. Zahner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:10
CPC Classifications
E; E04; E04G; E04G1/00; E04G1/18; E04G1/20; E04G1/34
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
227 words
A lifting device comprising: a base framework; first and second elongated upright supports pivotally coupled with said framework in spaced apart relationship, each of said supports being movable from a collapsed position in generally horizontal disposition to an extended position in generally vertical disposition; first and second platform supporting means for raising and lowering an object, said means being mounted on said first and second upright supports, respectively, for movement longitudinally therealong between raised and lowered positions when said supports are in their extended positions; a platform member substantially spanning the distance between said supports and adapted to be coupled therewith; means for mounting one end of said member on each of said platform supporting means, each of said mounting means comprising a bracket presenting a coupling with said supporting means for accommodating pivotal movement of said supporting means relative to said platform mounting means for approximately 90°, an elongate section extending away from said pivotal coupling and means coupled with said elongate section for coupling with said platform member whereby the latter may be lowered to a plane lying below the plane of the pivotal point of one of said supports a distance at least equal to the width of the other of said upright supports; and means coupled with said platform supporting means for moving the platform member up and down along said upright supports.
Claim 2
Dependent Claim
227 words
A lifting device comprising: a base framework; first and second elongated upright supports pivotally coupled with said framework in spaced apart relationship, each of said supports being movable from a collapsed position in generally horizontal disposition to an extended position in generally vertical disposition; first and second platform supporting means for raising and lowering an object, said means being mounted on said first and second upright supports, respectively, for movement longitudinally therealong between raised and lowered positions when said supports are in their extended positions; a platform member substantially spanning the distance between said supports and adapted to be coupled therewith; means for mounting one end of said member on each of said platform supporting means, each of said mounting means comprising a bracket presenting a coupling with said supporting means for accommodating pivotal movement of said supporting means relative to said platform mounting means for approximately 90°, an elongate section extending away from said pivotal coupling and means coupled with said elongate section for coupling with said platform member whereby the latter may be lowered to a plane lying below the plane of the pivotal point of one of said supports a distance at least equal to the width of the other of said upright supports; and means coupled with said platform supporting means for moving the platform member up and down along said upright supports.
Claim 3
Dependent Claim
36 words
The invention of claim 1, wherein said hangar bracket comprises a generally L-shaped component with the vertical leg thereof presenting said elongate section and the uppermost end thereof being bent back to provide said pivotal coupling.
Claim 4
Dependent Claim
30 words
The invention of claim 1, wherein each of said first and second upright supports comprises a pair of standards disposed in spaced apart relationship at one end of said framework.
Claim 5
Dependent Claim
30 words
The invention of claim 3, wherein each of said platform supporting means comprises spaced apart plate means having roller means coupled therewith and adapted to ride along said upright supports.
Claim 6
Dependent Claim
79 words
The invention of claim 4, wherein is included a header beam extending between each pair of upright standards adjacent the ends of the latter which are farthest removed from said framework, said means for moving the platform supporting means comprising cables coupled with each of said platform supporting means, there being at least one cable pulley mounted on each of said header beams and over which a cable is trained, and winch means for winding and unwinding said cables.
Claim 7
Dependent Claim
15 words
The invention of claim 5, wherein is included power means for operating said winch means.
Claim 8
Dependent Claim
55 words
The invention of claim 6, wherein is included a cable secured to each of said platform supporting means adjacent each of said upright standards, there being at least three pulleys mounted on each of said heater beams, one of said cables being trained over one pulley and the other cable being trained over two pulleys.
Claim 9
Dependent Claim
32 words
The invention of claim 7, wherein said winch means comprises an elongated winding drum extending substantially the length of said framework whereby all of said cables may be wound on said drum.
Claim 10
Dependent Claim
69 words
The invention of claim 5, wherein is included a safety lever stop coupled with each of said platform supporting means and operable to engage said upright support to stop movement of said platform supporting means, each of said stops being urged in the direction of an adjacent upright support by yieldable biasing means and held against movement by one of said cables so long as the latter is taut.
Claim 11
Dependent Claim
85 words
The invention of claim 3, wherein is included an angle brace extending between one of said upright supports of each pair of supports and said base framework, the latter including an elongated guide track for one end of each of said braces whereby said one end moves along said guide trace as said upright supports are moved between collapsed and extended positions, and means for locking said one end relative to said track when the brace and corresponding upright support are in their extended positions.
Claim 12
Dependent Claim
53 words
The invention of claim 10, wherein said guide track comprises a tubular member having opposed slots for coupling said one end of each of said braces therewith, and yieldable biasing means disposed in said tubular member and coupled with said one end of each brace for urging the latter into its extended position.
Claim 13
Dependent Claim
20 words
The invention of claim 3, wherein said base framework comprises horizontal telescoping feet for increasing the stability of the framework.
Claim 14
Dependent Claim
33 words
The invention of claim 12, wherein two telescoping sections are disposed at each end of the framework, each pair of sections at one end of the framework being offset relative to one another.
Claim 15
Dependent Claim
51 words
The invention of claim 3, wherein is included a telescoping tongue member mounted on said base framework, said tongue member being movable in the direction of the longitudinal axis of the framework from a retracted position substantially underlying the plane of the framework to an extended position projecting from said plane.
References Cited (Backward Citations)
US2354906A
Cited
US2420903A
Cited
US3130815A
Cited
US3378101A
Cited
US3463265A
Cited
US3576233A
Cited
US3682271A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-04 | 1980-07-05 | 1981-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-04 | 1984-07-05 | 1985-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-04 | 1988-07-05 | 1989-01-04 | $7700.00 | Window Closed / Lapsed |