Patent US3817346A successfully refreshed from Google Patents.
US3817346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mobile scaffolding
Assignee: Individual
•
Filing: 1972-08-21
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Granted: 1974-06-18
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Expires: 1992-08-21
Abstract
Abstract There is disclosed a mobile scaffolding which is powered by self contained electrical storage batteries. The electric drive is mechanically linked to the lift mechanism of the scaffolding by mechanical means comprising screw means and a mating nut means interconnected by rolling means to provide a high efficiency coupling. The lift mechanism employs very compact spring means which is biased to extend the lift mechanism from its contracted position to provide a force that supplements the electric drive when the mechanism has the most unfavorable lever moment for extension of the scaffolding. The unit has a self contained power means for mobility and a self contained directional control means with remote control means whereby the entire unit can be controlled from the scaffolding platform with a single lever that actuates the lift, drive and steering motors.
Inventors
- 👤 D Wehmeyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:26
CPC Classifications
E; E04; E04G; E04G1/00; E04G1/18; E04G1/22; B; B66; B66F; B66F11/00; B66F11/04; B66F11/042; E04G1/24; E04G2001/242; E04G2001/244
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
334 words
A mobile scaffolding machine having: a platform; a base, axle means carried thereon, wheels on said axle means whereby said scaffolding is mobile; an extendible assembly mechanically interlinking said platform and base and comprising at least one pair of arm members joined together in a pivotable connection at an intermediate point of their length; platform attachment means securing a pair of free ends of said extendible assembly to said platform; base attachment means securing the opposite pair of free ends of said extendible assembly to said base; said attachment means including longitudinal channel means carried on each of said platform and base and wheeled means engaged therein and carried by at least one of each of the pairs of free ends of said assembly to permit its sliding engagement with its respective platform or base; lift means operatively attached to at least one end of said extendible assembly comprising screw means positioned transversely to the direction of extension of said assembly, screw engagement means cooperative therewith, electric lift motor means, interconnecting means linking said motor in rotational driving relationship to one of said screw and screw engagement means and means securing at least one of said pair of free ends at said one end of said extendible assembly to at least one of said screw and screw engagement means whereby rotational movement of said motor effects the extension and retraction of said assembly; resilient means comprising compression coil spring means carried on said scaffolding coaxially with said screw means to engage said extendible assembly between its retracted position and a partially extended position having said arm members at an angle no greater than about 45 degrees to the horizontal and to urge extension of said assembly from said retracted position to said partially extended position whereby the force stored in said resilient means by retraction of said assembly is available for supplementing the force of said motor means through the positions of said assembly having the most disadvantageous lever moments to said screw means.
Claim 2
Dependent Claim
334 words
A mobile scaffolding machine having: a platform; a base, axle means carried thereon, wheels on said axle means whereby said scaffolding is mobile; an extendible assembly mechanically interlinking said platform and base and comprising at least one pair of arm members joined together in a pivotable connection at an intermediate point of their length; platform attachment means securing a pair of free ends of said extendible assembly to said platform; base attachment means securing the opposite pair of free ends of said extendible assembly to said base; said attachment means including longitudinal channel means carried on each of said platform and base and wheeled means engaged therein and carried by at least one of each of the pairs of free ends of said assembly to permit its sliding engagement with its respective platform or base; lift means operatively attached to at least one end of said extendible assembly comprising screw means positioned transversely to the direction of extension of said assembly, screw engagement means cooperative therewith, electric lift motor means, interconnecting means linking said motor in rotational driving relationship to one of said screw and screw engagement means and means securing at least one of said pair of free ends at said one end of said extendible assembly to at least one of said screw and screw engagement means whereby rotational movement of said motor effects the extension and retraction of said assembly; resilient means comprising compression coil spring means carried on said scaffolding coaxially with said screw means to engage said extendible assembly between its retracted position and a partially extended position having said arm members at an angle no greater than about 45 degrees to the horizontal and to urge extension of said assembly from said retracted position to said partially extended position whereby the force stored in said resilient means by retraction of said assembly is available for supplementing the force of said motor means through the positions of said assembly having the most disadvantageous lever moments to said screw means.
Claim 3
Dependent Claim
64 words
The scaffolding machine of claim 1 wherein said base carries: electric power means, means linking said power means to at least one of said wheels to drive said scaffolding, directional control power means, means linking said control power means to at leat one of said wheels to steer said scaffolding, and a source of electrical energy with connector means to said electric power means.
Claim 4
Dependent Claim
20 words
The scaffolding machine of claim 1 wherein said extendible assembly comprises two assemblies of arms located at each side thereof.
Claim 5
Dependent Claim
19 words
The scaffolding machine of claim 3 wherein each of the extendible assemblies of arms comprises four arms pivotably interconnected.
Claim 6
Dependent Claim
27 words
The scaffolding machine of claim 4 wherein each of said platform and base attachment means includes a set of fixed brackets at one end of said scaffolding.
Claim 7
Dependent Claim
21 words
The scaffolding machine of claim 5 wherein screw and screw engagement means are positioned at each side of the scaffolding base.
Claim 8
Dependent Claim
63 words
The mobile scaffolding machine of claim 1 wherein said screw means comprises at least one screw rod longitudinally carried by said base with one end thereof secured to said one end of said extendible assembly and the oPposite end thereof extending to said interconnecting means, the latter comprising a rotating nut drive member engaged by said screw rod in a thread drive housing.
Claim 9
Dependent Claim
49 words
The mobile scaffolding machine of claim 7 wherein said free end of said screw rod extends past said threaded drive housing and into sliding engagement with a tubular member having a flanged abutment and coxially supporting said compression coil spring means between said abutment and said threaded drive housing.
Claim 10
Dependent Claim
290 words
A mobile scaffolding machine comprising: a rectangular mobile base with dirigible wheels; a pair of spaced-apart parallel channel means located on opposite sides of said base, each of said channel means having a pivot fixture located at one end thereof; a separate dolly means reciprocally confined in each of said channel means; a first screw rod having one end connected to one of said dolly means and extending coasially therefrom in its associated channel means toward its pivot fixture; a second screw rod having one end connected to the other of said dolly means and extending coaxially therefrom in its associated channel means toward its pivot fixture; a first thread drive housing fixedly mounted intermediately of one of said channel means and having a rotating nut drive member engaging the threads of said first screw rod; a second thread drive housing fixedly mounted intermediately of the other of said channel means and having a rotating nut drive member engaging the threads of said second screw rod; drive means in each of said housing for rotating its drive nut member; a rigid cross shaft interconnecting said drive means of said housings for simultaneous rotation thereof; an electric drive motor drivingly connected to said cross shaft where said dolly means can be simultaneously advanced and retracted relative to their respective pivot fixtures; a pair of vertically oriented scissor-type lift arms, one of said pair connected between one of said dolly means and its pivot fixture and the other of said pair connected between the other of said dolly means and its pivot fixture whereby a work platform connected to said pair of vertically oriented lift arms is raised and lowered as said dolly means are simultaneously reciprocated in their associated channel means.
Claim 11
Dependent Claim
290 words
A mobile scaffolding machine comprising: a rectangular mobile base with dirigible wheels; a pair of spaced-apart parallel channel means located on opposite sides of said base, each of said channel means having a pivot fixture located at one end thereof; a separate dolly means reciprocally confined in each of said channel means; a first screw rod having one end connected to one of said dolly means and extending coasially therefrom in its associated channel means toward its pivot fixture; a second screw rod having one end connected to the other of said dolly means and extending coaxially therefrom in its associated channel means toward its pivot fixture; a first thread drive housing fixedly mounted intermediately of one of said channel means and having a rotating nut drive member engaging the threads of said first screw rod; a second thread drive housing fixedly mounted intermediately of the other of said channel means and having a rotating nut drive member engaging the threads of said second screw rod; drive means in each of said housing for rotating its drive nut member; a rigid cross shaft interconnecting said drive means of said housings for simultaneous rotation thereof; an electric drive motor drivingly connected to said cross shaft where said dolly means can be simultaneously advanced and retracted relative to their respective pivot fixtures; a pair of vertically oriented scissor-type lift arms, one of said pair connected between one of said dolly means and its pivot fixture and the other of said pair connected between the other of said dolly means and its pivot fixture whereby a work platform connected to said pair of vertically oriented lift arms is raised and lowered as said dolly means are simultaneously reciprocated in their associated channel means.
Claim 12
Dependent Claim
52 words
The mobile scaffolding machine as defined in claim 9 wherein a compression spring is coaxially mounted between each threaded drive housing and the end of its screw rod extending therefrom toward its associated pivot fixture whereby said compression spring will be compressed as its associated dolly moves away from its pivot fixture.
Claim 13
Dependent Claim
108 words
The mobile scaffolding machine of claim 10 wherein said compression springs are operative only to bias their associated screw rods when said scissor-type lift arms are between their most retracted position and a partially extended position having said arms at an angle no greater than about 45 degrees to the horizontal and to urge extension of said lift arms from their retracted position to said partially extended position whereby the force stored in said compression springs by retraction of said lift arms is available for supplementing the force of said motor through the positions of said lift arms having the most disadvantageous lever moments to said screw rods.
Claim 14
Dependent Claim
37 words
The mobile scaffolding machine as defined in claim 9 wherein the electric drive motor is a variable speed drive motor so the speed of simultaneous movement of said dolly means in their associated channels can be controlled.
Claim 15
Dependent Claim
44 words
The mobile scaffolding machine defined in claim 12 wherein the electric drive motor is a DC drive motor and its speed is controlled with a control circuit employing a SCR operable to pulse the drive motor at different frequencies to selectively change its speed.
Claim 16
Dependent Claim
39 words
The mobile scaffolding machine defined in claim 13 wherein a control circuit is provided to change the pulse rate of the SCR, said control circuit having a manually operated device for chAnging the pulse rate of the SCR circuit.
Claim 17
Dependent Claim
93 words
The mobile scaffolding machine defined in claim 14 wherein the manually controlled device includes a lever means which includes a reversing switch and a potentiometer whereby advancing the lever from a neutral position in one direction will cause the motor to drive clockwise at a rate proportional to the displacement of said lever from a neutral position and the advance of said lever from said neutral position in the other direction will cause said motor to rotate in a counter-clockwise manner proportional to the distance said lever is moved from said neutral position.
Claim 18
Dependent Claim
32 words
The mobile scaffolding machine as defined in claim 15 wherein the lever means is mounted on the work platform whereby the ascent and descent of the platform can be controlled directly therefrom.
Claim 19
Dependent Claim
48 words
The mobile scaffolding machine as defined in claim 15 wherein the rectangular mobile base with dirigible wheels includes an electric drive motor and the control circuit can be switched so the lever means can be utilized to control the movement of said mobile base in speed and direction.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |