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Publication numberUS2948363 A
Publication typeGrant
Publication dateAug 9, 1960
Filing dateAug 11, 1955
Priority dateAug 11, 1955
Publication numberUS 2948363 A, US 2948363A, US-A-2948363, US2948363 A, US2948363A
InventorsHopfeld Fred P
Original AssigneeGrand Specialties Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Telescoping elevators
US 2948363 A
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Description  (OCR text may contain errors)

Aus. 9, 1960 `Fl P. HOPFELD TELESCOPING ELEVATORS Filed Aug'. 1l,I 1955 2 sheets-sheet 1 linnn i, @uf

Invexz for Fred R J70/feld Aug. 9, 1960 F. |=j. HoPFELD 'rELEscPING ELEvAToRs 2 'Sheets-Sheet 2 FiledAug. 11, 1955 .In ver2 for Y. R H w m s I Fred IF v11| W United States Patent TELESCOPIM; ELEvAroRS Fred P. Hopfeld, Elmwood Park, lll., assigner to Grand Specialties Company, Chicago, Ill., a corporation of Illinois Filed Aug. 11, 1955, Ser. No. 527,851 2 Claims. (cl. 18s-14) This invention relates to a telescoping elevator that is particularly adapted to support and erect a work tower.

In construction and repair work, and in the installation of xtures and the like, itis often necessary to work at rather extreme heights under circumstances that do not warrant the erection of scaiolding of the usual kind, and in these instances it is desirable that a work platform be afforded capable of elevation to dilierent heights. One form in which it has been proposed to accomplish this is to provide. a platform adapted to be elevated by a hydraulically operated piston, but to accommodate the various elevations to which it may be desired to position, the ,platform a piston having an unusuallylong stroke is required. For instance, to elevate the platform toV a thirty-five foot height a thirty-five foot stroke is required for the piston. Such arrangements involve unstable structure and the expense of the hydraulic system entailed is often prohibitive.

In view of the foregoing, the primary object of the present invention is to arrange va Working platform on a sectional telescoping elevator in such a way that the sections `oli the elevator are adapted to nest one in the other in collapsed or unerected condition and to undergo selferection by imparting Vertical upward movement to one section through a relatively short distance that is multiplied with respect to the other sections telescoped therein. In this way, a hydraulic pistonor the like having a -relatively shortstroke may be used to erect a tower for supporting a .'work platform at a predetermined height, and the elevator may be readily moved about in collapsedV condition. s

I A further object of the present invention is to alord relatively compact and stable elevator structure comprising a plurality of nested or telescoped elevator sections coupled one to another in such a Way that the distance through which a iirst such movable section is advanced is multiplied by a substantial factor for the remaining movable sections. By supporting a work platform on the last of the nested sections, the platform will be elevated through a distance which is a multiple of the distancethrough which the lirst section is advanced.

. Further objects of the present invention are to enable a telescoping elevator of the foregoing kind to be propelled manually -in a compact collapsed condition to the position of use and to be readily erected as a tower to the desired height; to so construct the sections of the elevator that the platform will be stably supported in its elevated position; and to greatly simplify the construction `and enlarge the flexibility of erectable work platforms. .Y

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, byway of illustration, show a preferred embodiment of the present invention and the principle thereof and what l now consider to be the best mode in which I have contemplated applying that principle. Other embodiments ofthe invention embodying the same or equiv- {alent principle may be used and structural. changes may be made as Vdesired by those skilled in the art Without departing from the present invention and the purview of the appended claims.

In the drawings:

Fig. 1 is a perspective view of one form of the present invention in a collapsed or unerected condition;

Fig. 1A is a detail view of certain supporting structure; f

Fig. 2 is a perspective view of the elevator and platform in an erected condition; f

Fig. 3 is a schematic illustration of the arrangement of the elevator sections; s

Fig. 4 is a fragmentary perspective of structure at corner portion of the elevator;

Fig. 5 is a fragmentary elevation of the elevator in a partially erected condition;

Fig. 6 is a fragmentary top plan view of a corner of the collapsed elevator; and

Fig. 7 is a section through Fig. 6 immediately below the idlers and the idler supports.

The present invention is shown in Figs. 1 and 2 as embodied in a telescoping elevator 20` which includes a caged platform 2l adapted to be raised as shown in Fig. 2 to a predeterminedheight, and the way in which this is accomplished will be presently set forth.

The elevator in the present instance is in the main constructed ofangle bars that are welded together to afford a plurality of box-like sections that are telescoped one in another. Thus,l there is rst provided an outer rectangular or box-like section F-1 including four correspondingly spaced vertical angle bars 26, Fig. l, and these bars are reinforced by diagonal cross bars 27 extended between the upper and lower ends of the members 2.6. Extended horizontally between the respective vergt-ical members 26 are longitudinal tie bars 28 and transverse tie bars 29 serving to space the vertical members 26 of the frame F-l in the desired dimension. The vertical members 26 at each corner of the outer section F-l are disposed so that the channels thereof face inwardly as shown in Figs. 6 and 7, and the reason for this will be explained below.

SectionF-l at the bottom is secured as by welding to a pair of longitudinal parallel angle bars 31 disposed in la horizontal plane, and these in turn at the opposite endsrare connected by transverse angle bars as 3'2 alording va base structure 35, Fig. 1, for the elevator. At one end of the base 35, a pair of relatively short up-rights 36 are provided, and a pair of reinforcing bars as 37 are extended upwardly from the up-nights 36 to the top of section F-L Preferably, transverse tie bars 38 are extended between the up-rights 36, the bars 37, and the angles 26 forming a part of the section F-Z as shown in Fig. A1. In like manner, long tie bars 39 are extended between the reinforcing bars 37 and the postsy 26 on either side of section F-1, and tie bars 39A of somewhat greater length are extended between the short up-rights 36 and the vertical members 26 at either side of the frame F-1. At the four corners of the base 35, casters 40 Kare journaled for supporting Wheels as 41 which enable the elevator 203to be propelled manually to position of use.

Supported adjacent one end Vof the base 35, in the space between section F-l and the up-rights 36, is a plate 43, Fig. l, and anchored to the plate 43 is a motor and pump assembly MPV adapted to furnish fluid under pressure to ia Acylinder 45, Fig. 5, and they fluid thusfurnished is provided by a reservoir 46k bracketed to an up-right 47 as shown in Fig. 1.

' Under the present invention, a series` of inner box-*like elevator sectionsF-Z, F-3, F4, F-S and ,F-'which are of diminishing size in the order mentioned are 'telescopically arranged within the outer section F-l that is fixed to the base 35, so that when the elevator sections are in a collapsed or completely nested condition as shown in Fig; l, the platform 21 which is carried by sectionF- is just above the tie bars 28 and 29 that are connected between the upper ends of the vertical members 26 included in the section F-l.

The various sections of the elevator thus aorded are constructed quite similar to the outermost section F-l except for certain dilerences to be mentioned. Thus, the elevator sections F-Z through F-6 each include vertical langle bars as 26A, Fig. 6, having flanges fl extending outwardly so that the channels thereof face outwardly as shown in Fig. 7. The elevator sections F2 through F-S also include vertical angle bars 26B which have flanges fl welded in back-to-back relation to like opposed anges fl'. of the angle hars 26A. The other flanges fl" of the angles 26B project inwardly as shown in Figs. 6 and 7 so that the channels thereof face inwardly as shown in Fig. 7. Thus, each section F-Z through F-S includes at each of the four corners, two vertical angle bars; section F-l includes at each corner but one angle bar 26 with its channel facing inwardly; and section F-6 includes at each corner but one angle bar 26A with its channel facing inwardly.

'It will be appreciated that the distance by which the vertical angle bars in each section of the elevator are separated will be of diminishing order enabling the various sections to be telescoped one within the other as shown particularly in Figs. 5, 6 and 7. The vertical bars 26A in each instance are spaced at either end by longitudinal and transverse tie bars as 28A and 29A respectively, and are reinforced by diagonal bars 27A at the opposite sides thereof that correspond to the sides of the frame F-l that are reinforced by the diagonal bars 27.

The cylinder 45 includes a piston 45-P, Fig. 5, and this piston is adapted to be elevated by iiuid under pressure as aforesaid. The lower end of the cylinder 45 is mounted in a socket 49 which is rigidly anchored to a pair of transverse I-beams 50 and 51, Fig. 5, which extend between the two longitudinal angle bars 31 that are included in the base 35 of the elevator.

Y Vertical upward movement of the piston 45P is imparted to the elevator section F-Z which is the one next innermost with respect to the section F-1 that is lixed to the base 35. To this end, the piston 45P carries a cross head 53, Fig. 5, and connected to the cross head 53 in depending relation are a pair of transmitting rods 54 and 55. At their lower ends, the transmitting rods 54 and 55 are anchored in a pair of sleeves 58 and 59, and these sleeves in turn are Welded to the inner faces of a pair of transverse I-bars 61 and 62 welded at respective ends to the longitudinal tie bars as 28A, Fig. 5, trhat are secured to the bottom of the elevator section From the foregoing, it will be seen that when iluid under pressure is furnished to the bottom of cylinder 45 to elevate the piston 45'P, upward movement of the piston 45P is transmitted to the elevator section F-2 which then commences to advance upwardly and such advancing movement of the elevator section F-Z in turn is imparted to the remaining elevator sections F-3 through F-6 as will now be described.

As shown in Fig. 7, the longitudinal tie bars 28A at the top and bottom of the elevator sections F-Z through F-6 are secured to the upper and lower ends of the vertical angle bars 26A, and in sections F-2 through F-S the transverse tie bars 29A are secured to the upper and lower ends of the vertical angle bars 26B which, as was mentioned, are welded to the angle bars 26A so that the channels thereof face inY opposite directions. This enables the sections of the elevator when undergoing expansion to be stabilized and guided in a way to be described. inasmuch es there is no further elevator section nested within section F-6, this section does not include at the four corners thereof an auxiliary angle bar 26B; in this instance, therefore, both the tie bars 28A and 29A are welded to the single vertical angle bar 26A.

As shown in Figs. 4 and 6, a relatively short mounting plate 7i) is welded to the tie bars 28A and 29A where these are in juxtaposition at the upper four corners of each of the elevator sections F-2 through F-S so as to overlay the upper ends of the vertical angle bars 26A and 26B. The mounting plates 74) thus provided each serve to support idlers at the corresponding corner as will be explained and since in the arrangement entailed sections F-1 and F-6 carry no such idlers, mounting plates as 70 are not afforded for these sections as will be observed from Fig. 6.

In View of the fact that the idler arrangement at the four corners of each :section F-Z through F-5 is identical, the description to follow will pertain to but one corner only of each such elevator section, bearing in mind that each section F-2 through F-S carries four idlers, one at each upper corner.

Thus, a pair of spaced apart vertical brackets 72, Fig. 4, are welded to the upper face of each mounting plate '70. A pin 74 is extended between these brackets and serves as an axle for an idler in the form of a sprocket 75 journaled thereon.

An anchor bar 76 is rigidly secured at either end, as shown in Fig. 4, to the vertical angle bars 26 which are on opposite sides of the elevator section F-1. There will be two such anchor bars on opposite sides of the section F-l, and these are arranged substantially below the top of section F-ll as will be noted from Fig. 5. A flexible coupler or connector in the form of a chain 78, Fig. 4, is attached at one end to a lug 79 supported by the anchor bar 76, and this chain is directed upwardly about the idler 75 on section F-2 and then downwardly to an anchor lug 81 welded to the angle bar 26A that is included in the elevator section F3. The anchor lug 8l is spaced above the bottom of section F-3 as will be observed from Fig. 5.

The foregoing arrangement regarding the way in which a coupler as 78 is connected at one end to an anchor on an outer section as F-l, and at the opposite end to an anchor on an alternate inner section as F-3 while being passed over an idler on an interposed one of the telescoped sections as F2 is repeated for the remaining ones of the sections. Thus, a chain 7.8-2, Fig. 5, is connected at one end to an anchor lug 792 secured to section -F-2, and this chain is then directed upwardly about an idler sprocket 75-3, Fig. 6, on interposed section F-S and then is directed downwardly to an anchor lug 81--4 adjacent the bottom of the alternate section F-4. Likewise, a third chain 78-3 is secured at one end to an anchor lug 79--3 carried by section F-3 and then is played about an idler 75--4 carried at an upper corner of section F-4 that is interposed between sections F-S and F-S. Chain 78-3 at the other end is then anchored to a lug 81-5 adjacent the bottom of the alternate section F-S. Finally, a chain 78-4 is c011- nected at one end to an anchor 79-4 on frame section F-4, played about an idler on section F-S and then is directed downwardly and attached to a lug 81-6 that is xed to section F-6.

Y' As was mentioned, upward movement of the piston 45P is imparted to section F-Z through the transmitting links 54 and 55. When this occurs, section F2 is first lifted from the bottom, and the idlers 75 at the upper four corners of section F-Z will likewise advance upwardly. As a consequence, the four chains as 78 will be placed under tension and since these are anchored at one end to section F-l, which is immovable, the chains 7S at the ends connected to the lugs 81 on name F-S and will lift the latter to advance simultaneously upwardly with section F-Z as indicated in Fig. 4." In like manner, upward advancing movement of section F-3 places the four chains as '78-2 under tension so that section F-4 will commence to advance upwardly with sections F-Z and F-3 and the way in which sections l`-`5 and F-6 are likewise lifted will be readily apparent from Fig. 5 which illustrates the elevator at an intermediate state of expansion or erection. It will be appreciated that two chains for lifting each section could be resorted to,'one located medially on either side, but by using four chains increased stability from the standpoint of tilting is attained and equalized expansion of the several sections is assured. It will be appreciated that the sections in eifect are suspended or hung by the chains, so that each chain can be adjusted to take up wear or align the several sections of the collapsed elevator.

In Fig. 3, the mechanical advantage that is involved is illustrated diagrammatically. It will be observed that the telescoped sections of the elevator are indicated by lower case characters f-l through f-6, section f-1 being immovable and section f-6 being the one adapted to carry the work plateform 21. When the initial lifting force is applied to the bottom of section f-Z, this section will be elevated through a relatively short distance x corresponding to the extent of movement of the piston 45P. Each section f-3 through f-,6 will likewise advance simultaneously with section f-2 through a like predetermined or selected distance x, and consequently the last of the movable sections f-6 will attain a height that is a multiple of the distance x. In this instance, since there are live movable sections, the last section f-6 will attain a height 5x as indicated in Fig. 3 in comparison to the elevator in a collapsed or unerected condition.

It was mentioned that the arrangement of the vertical angle bars 26, 26A and 26B enables the various tele` scoping sections to be guided and stabilized in a positive manner, and this is accomplished by having resort to complementally related guide and stabilizing means which are adapted to engage the flanges or plates as fl and fl'" of these vertical angle bars to aord what in eifect are complemental guide members on respective adjacent sections of the elevator. Such means include short plates 90 which in section F-l, as shown particularly in Fig. 7, are welded at one edge to the inner faces of those iianges of the vertical members 26 that are parallel to the transverse tie members 29. In section F-Z through F-S, the plates 90 are welded in a similar relation to the flanges fl of the angles 26B. Each such plate 90 at the opposite or inner edge has welded thereto a relatively short full-round bar 91, and these bars are adapted to engage the outer faces of those flanges fl" of the angles 26A which are parallel to the transverse tie bars as 29A. The guide elements thus afforded are disposed at the upper ends of the vertical members 26, 26A and 26B, beneath the mounting plates 70, as will be observed in Fig. 4. Since during expansion of the elevator sections there will be relative sliding movement between the guide elements 91 and the vertical angle bars 26A, the guides 91 will serve to hold the sections for accurate parallel movement.

In a similar fashion, guides of the foregoing kind are also provided at the lower ends of the elevator sections. Thus, relatively short plates 95 are secured as by rivets or the like to the outer faces of those flanges fl of the vertical members 26A that are parallel to the longitudinal tie members as 28A. The plates 95 at the outer edge carry relatively short full-round bars 96, and the arrangement is such that the guides 96 engage the inner faces of the ianges of the angles 26 that are parallel to the ties 29 in section F-l and the inner faces of the flanges fl of the angles 26B in sections F-Z through F-S, as shown particularly in Fig. 7.

The work platform 21 which is carried by the innermost one of the telescoped sections may be supported in different ways, but the preferred way of accomplishing this is to provide reinforcing runners 98, Figs. 1 and 5, in spaced parallel relation at the underside of the work platform 21 and to secure the outer ones of these runners as by a weld or the like to the vertical members 26A of section F-6 as shown in Fig. 5. In this connection, it will be appreciated that the hydraulic cylinder 45 vand the piston 45P controlled thereby will be centered within section F-6 below the work platform 21.

Because of the extreme height to which the work platform 21 may be elevated under some circumstances, as shown in Fig. 2, it is desirable to provide stabilizers at the base of the elevator 20. In the present instance, this is attained by a pair of foldable outriggers at either side of the base structure. Each Outrigger includes a pair of tubular members as and 101, Figs. 1 and 2, that are pivoted at one end on plates 103l that are secured at opposite ends of the horizontal bars 39A, At the ends of the tubular members 101 and 103 opposite the ends pivoted to the plates 103, horizontal cross members in the form of tubes 105 are attached to plates 106. The plates 106 are each welded to one side of a sleeve-like nut 107, and the nuts 107 in turn are welded to the upper ends of the members 100 and 101 as viewed in Fig. l, which is to say the ends opposite the ends pivoted to the plates 103.

Screws 108 are threadedly mounted in the nuts 107, and the nuts 108 at one end are provided with Hat, circular ground-engaging plates 110. At the ends opposite the plates 110, the screws 108 are provided with short handles 110 enabling the plates 110 to be selectively positioned.

vSwiveled on a pin (not shown) carried by the plates 106 are connector rods 112 and 113, and the ends of these rods opposite the ends swiveled on the plates 106 are provided with in-turned ears 112E and 113B. for a purpose to be described.

Preferably, the outriggers are reinforced by cross braces 115, Fig. 2. The stabilizing Outrigger means may be held in an upwardly folded relation inwardly against the stationary elevator section F-l vin any convenient manner, and when it is desired to stabilize the elevator these are then unfolded, as shown in Fig. 2, so that the plates 110 are at ground level. The -in-turned ears 112B and 113B are then sprung into openings formed in lugs as 115 that 'are secured at opposite ends of the angle bars 31, thereby locking the outriggers in an unfolded or stabilizing relation as shown in Fig. 2. If uneveness is encountered, the screws 108 are adjusted to accordingly raise or lower the ground-engaging plates` 110.

It is desirable to prevent the elevator 20 from drifting, either when collapsed or erected. Consequently, a brake including a frictioned ground-engaging shoe 120, Pig l, is supported by a bracket 122 at one end of the base 35. The shoe is adapted to be lowered to operative position, and released to inoperative position, in a known way by a foot pedal 123.

It will be seen from the foregoing that under the present invention there is afforded 'a telescoping elevator adapted to undergo erection or expansion from a collapsed condition by a force applied to a section that is interposed between what may be termed alternate sections, that is, telescoping sections on either side of the interposed section. The force thus applied is transmitted by ileXible couplers or connectors arranged in such a way that the connectors at one end are adapted to be tensioned on one of the aforesaid alternate sections so as to impart at the oposite end lifting movement simultaneously to the other alternate section. Repeating this arrangement enables the last of the alternate sections to be elevated to a height which is a substantial multiple of the `distance through which the initial lifting force is applied.

Thus, while 'I have illustrated the preferred embodiment of the invention, it is to be understood that this iS capable of variation and modication, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. An elevator of the kind described adapted to be erected from a collapsed condition and comprising in nested assembly, a plurality of generally cubical sections of diminishing lateral dimension telescoped one within another and including a first or outer such section and a last r innermost section and a plurality of intermediate sections between said iirst and last sections, the outer or iirst one of said sections being stationarily mounted on a base structure having wheels thereon enabling the elevator to be manually moved about, idlers carried at the upper end of said intermediate sections, iiexible connectors each attached at one end to anchor means on an outer section below the top thereof, passed over the idlers on the next inner section and then attached at the other ends to anchor means on the second next inner section, a hydraulically operated piston substantially centered within the innermost one of said sections and adapted through transmitting links to apply a lifting force to the bottom of the outermost one of said intermediate sections, a work platform carried by the innermost one of said sections so as to be elevated to a height that is a multiple of the distance through which the outermost one of said intermediate sections is advanced, said intermediate sections each having at the four corners thereof elongated vertical angle bars arranged in substantially back-to-back relation with the channels thereof facing inwardly and outwardly relative to the assembly respectively in opposite directions, the first or outer section having a like angle bar at a corner thereof with the channel of that bar facing inwardly relative to the assembly and the last or innermost section having a like angle bar at a corner thereof with the channel of that bar facing outwardly relative to the assembly, and a ilange of each of said angle bars having fixed thereon a iiat narrow guide plate projecting therefrom a substantial distance and fitting in complemental fashion into the channel of the opposed angle bar, each corner of said 8 intermediate sections having two such guide plates one of which extends inwardly relative to the assembly and which is xed to the channel bar having the inwardly facing channel, and the other of which extends outwardd lly relative to the assembly and which is fixed to the channel bar having the outwardly facing channel.

2. An elevator of the kind described adapted torbe erected to a predetermined height from a collapsed condition and comprising in nested assembly, a plurality of generally cubical sections at least three in number telescoped one within another and including alternate sections and a section interposed between said alternate sections, the outer one of said alternate sections being immovably secured to a base structure, means to apply a lifting force to advance said interposed section through a selected distance, a flexible force transmitting means anchored at respective ends to said alternate sections and arranged to transmit said lifting force applied to the interposed section to the inner one of said alternate sections, said interposed section at each corner thereof having a pair of vertical angle bars disposed in substantial back-to-back relation so that the channels thereof vface inwardly and outwardly relative to the assembly respectively toward said alternate sections, said alternate 'sections at each corner thereof being provided with a guide plate fitting into the channel of the related angle bar on said interposed section, and the angle bars at each corner on the interposed section having fixed thereto a pair of guide plates projecting therefrom in opposite inward and outward directions relative to the assembly to engage solid surfaces provided at corners of said alternate sections.

References Cited in the tile of this patent UNITED STATES PATENTS -459,613 Newman Sept.A 15, 1891 1,188,283 LeBlanc June 30, 1916 2,204,671 Erickson et al June 18, 1940 2,402,579 Ross June Z5, 1946 2,57 6,3 89 Craighead et al Nov. 27, 1951

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3058543 *Mar 29, 1961Oct 16, 1962Prosser Clyde WPortable scaffolds
US3095945 *Dec 22, 1959Jul 2, 1963Lift A Loft CorpOverhead service unit
US3248831 *Jan 3, 1962May 3, 1966Craig Systems CorpTelescoping antenna mast
US3395776 *Mar 13, 1967Aug 6, 1968Hilary F. RussellSelf-locking safety support for ladders
US3439467 *Jan 26, 1967Apr 22, 1969Zip Up Lighting Tower Co IncPortable collapsible tower
US3664458 *Jan 20, 1971May 23, 1972Howard Arthur GLadder scaffold vehicle
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US4633625 *Sep 23, 1983Jan 6, 1987Man Gutehoffnungshuette GmbhPedestal unit having raisable and lowerable platforms
US4657112 *Apr 25, 1986Apr 14, 1987Up-Right, Inc.Mast construction for pedestal scaffold
US5310018 *Dec 17, 1992May 10, 1994Lahaie Jean JScaffold
US5324086 *Jul 13, 1992Jun 28, 1994Mordechai HammerDevice capable of positive extension and retraction using a casading force transfer
US5390760 *Apr 12, 1994Feb 21, 1995Upright, Inc.Safety guard for scissor lift
US7500334 *May 19, 2006Mar 10, 2009John Timothy StevensAccess tower
US20120043158 *Jul 27, 2011Feb 23, 2012Geoffrey George CampbellMast Lift with Screw Drive and Gas Strut
DE3034852A1 *Sep 16, 1980Apr 2, 1981Sante ZelliFahrbare teleskopische hubvorrichtung
DE9201136U1 *Jan 31, 1992Dec 3, 1992Goy, Wilhelm, 8881 Haunsheim, DeTitle not available
WO2010131065A1 *May 11, 2009Nov 18, 2010Ramirez Alfredo MedinaVery tall, vertical extendable/retractable structure
Classifications
U.S. Classification182/141, 182/17, 52/118, 182/69.4
International ClassificationE04G1/18, E04G1/22, B66F11/04
Cooperative ClassificationE04G1/22, B66F11/04
European ClassificationE04G1/22, B66F11/04
Legal Events
DateCodeEventDescription
Feb 10, 2006ASAssignment
Owner name: PATRIARCH PARTNERS AGENCY SERVICES, LLC, NORTH CAR
Free format text: PATENT COLLATERAL SECURITY AGREEMENT;ASSIGNOR:AMERICAN LAFRANCE, LLC;REEL/FRAME:017154/0385
Effective date: 20051214
Dec 28, 2005ASAssignment
Owner name: AMERICAN LAFRANCE, LLC, SOUTH CAROLINA
Free format text: PATENT ASSIGNMENT AGREEMENT;ASSIGNOR:LADDER TOWERS, INC.;REEL/FRAME:016945/0245
Effective date: 20051214