US3404752A

US3404752A - Scaffold

Info

Publication number: US3404752A
Application number: US560926A
Authority: US
Inventors: Stanley N Deines
Original assignee: Stanley N. Deines
Current assignee: STANLEY N DEINES
Priority date: 1966-06-23
Filing date: 1966-06-23
Publication date: 1968-10-08
Anticipated expiration: 1985-10-08

Description

S. N. DEINES SCAFFOLD 5 Sheets-Sheet 1 Filed June 23, 1966 INVENT OR STANLEY N. names Oct. 8, 1968 Filed June 25, 1966 5. N. DEINES SCAFFOLD 5 Sheets-Sheet 2 INVENTOR STANLEY u. DEINES Oct. 8, 1968 s. N. DEINES 3,404,752

SCAFFOLD Filed June 23, 1966 5 Sheets-Sheet 5 a INVENTOR STANLEY N. DEINES BY M Oct. 8, 1968 s. N. DEINES 3,404,752

SCAFFOLD Filed June 23, 1966 5 Sheets-Sheet 4 INVENTOR. STANLEY N. DEINES Oct. 8, 1968 s. N. DEINES 3,404,752

SCAFFOLD Filed June 25, 1966 5 Sheets-Sheet 5 laa 2|6 h i V214 INVENTOR. STANLEY N. DEINES United States PatentO 3,404,752 SCAFFOLD Stanley N. Deines, Denver, Colo. (RR. 1, Oberlin, Kans. 67749) Continuation-impart of application Ser. No. 429,733, Feb. 2, 1965. This application June 23, 1966, Ser.

A Claims. (cl. 182-148) ABSTRACT OF THE DISCLOSURE This application is a continuation-in-part of my copending patent application, Ser. No. 429,733, filed Feb. 2, 1965 and now abandoned.

This invention relates to a scaffold and more particularly to a vertically extendable scaffold structure having means for supporting a deck in various attitudes and particularly in a disposition inclined to the horizontal.

In the construction industry, scaffolds are used extensively for supporting men and equipment in working position adjacent to a building being constructed.

Scaffolds are used for many other purposes, however, most scaffolds are assembled and disassembled at a job site and such assembly and disassembly requires con-; siderable time of workmen and imposes some inconvenience in the transportation and use of conventional scaffolds. Further, most scaffold structures are inconvenient for use in supporting a deck in parallel relation to an inclined surface, such as an inclined ceiling or other similar structure adjacent to which workmen are performing various installations or finishing operations. It has been a problem properly to support men on a scaffold deck in parallel relation to an inclined ceiling or the like, so that they may work with ease and precision during the performance of various installations and/or finishing work, such as plastering or the like. Additionally, prior art scaffolds have lacked economi cally operable power equipment for vertically extending the scaffold and retracting them quickly and to thereby permit simple transportation and set-up of scaffold structures adjacent to a job site.

Accordingly, it is an object of the present invention to provide a novel scaffold having a generally rectangular structure provided with vertically extendable column structures at the corners of the scaffold structure and I 3,404,752 Patented Oct. 8, 1968 2 arrangement of vertically extendable telescopic column members for a scaffold structure which permit the construction of a very compact scaffold which may be readily and quickly extendable to substantial elevations and which may also selectively dispose a deck supported by the column members on a desired inclined position relative to the horizontal.

Another object of the present invention is to provide a novel arrangement of vertically extendable telescopic column members in which each assembly of column members at each corner of the scaffold structure of the invention is provided with a pair of hollow cylindrical members, one of which employs an upwardly extending telescopic element and the other supports a downwardly extending telescopic element and wherein a pair of hydraulic cylinders at each end of the scaffold are provided with corresponding downwardly extending and upwardly extending plungers, whereby the hydraulic cylinders cooperate with the column assemblies at the corners of the scaffold to permit cross bracing readily to be employed in interconnecting relation with the column assemblies of the corners of the scaffold. v

Further objects and advantages of the present invention may be apparent from the following specification, appended claims and accompanying drawings, i'n which:

"FIG. 1 'is an end elevational view of a scaffold in accordance with the present invention;

FIG. 2 is a diagrammatic view of the hydraulic power actuating system of the invention; I

FIG. 3 is a side elevational view of the scaffold structure of the invention;

FIG. 4 is a side elevational view of the scaffold structure of the invention similar to that shown in FIG. 3, but showing the scaffold structure vertically extended;

FIG. 5 is an enlarged fragmentary sectional view taken from the line 55 of FIG. 1;

FIG. 6 is an enlarged fragmentary plan sectional view taken from the line 6-6 of FIG. 1;

FIG. 7 is an enlarged fragmentary plan sectional view taken from the line 7-7 of FIG. 1; v 4

FIG. 8 is an .enlarged fragmentary sectional view taken from the line 88.of FIG. 1, showing by broken lines varying inclined positions of a deck structure of the present invention;

FIG. 9. is a reduced planview of the scaffold of the invention; 1

FIG. 10 is a side elevational view of a modified form of the invention, showing by broken lines an inclined disposition of the platform of the invention similar tothat shown in FIG. 4;

FIG. 11 is a view taken from the line .11-.11 of FIG. 10, showing an end of the-modified scaffold structure of the invention; :1

-FIG. 1-2 is a fragmentary plan view taken from the line 1212 of FIG. 10; and

FIG. 13 is an enlarged fragmentary plan sectional view taken from theline 13.13ofFIG. 10..

' Another object of the invention is to provide a novel scaffold structure having telescopic vertically extendable column members which are extendably operable by hydraulic cylinders furnished power by a contained hydraulic system'carried by the scaffold structure.

...A s shown in FIGS. 1, 3, 4 and 9 :of the drawings, the scaffold of the invention is a generally. rectangular scaffold having first-and second ends 10.and.12 and having opposite sides Hand 16. At corners .of these scaffolds are vertically extendable telescopic column assemblieslS, .20, 22 and 2,4. These column assemblies are arranged'in pairs, the column assemblies 18- and 20 being one pair and ;-the column assemblies. 221and 24 being another. pair,-.the pairs being'at respective opposite ends or-first=-and second Another object of the invention is to provide a power nds n tt e scaffold, 1 1 )-bcSt illFIG;

9.,ofthe drawings. The first pair 18 and 2.0 and the second pair .22 and 24 are connected together by removable braces, as will be hereinafter describedin detail, so that the pairsof vertically extendable telescopic column members may be maintained in assembled relation as unitary operating mechanisms and 'in this manner the braces removably connecting the pairs of column assemblies together permits the entire scaffold structure to be disassembled, if desired, for transportation in compact' form.

Each of the column assemblies18, 20,22 and 24 is composed of three concentric telescopic members and the construction of all of the column assemblies 18,20, 22 and 24 is substantially identical. A

As shown in FIGS. 5 and 7, the column assembly 18 is provided with an outside hollow cylindrical tubular member 26 internally of which a second hollow tubular member 28 is disposed and vertically slidably movable in the hollow tubular member 26. g

The hollow tubular member 28 is provided with an internal bore in which a third hollow tubular member 30 is vertically slidably mounted, all as shown best'in FIGS 5 and 7 of the drawings. j

The hollow tubular member 26 is provided with a vertically disposed slot 32 in the side wall thereof which is traversed by a tubular cross member 34 secured by welding or otherwise to the outer" surface of the hollow tubular member 28 at 36 so that when the hollow tubular member 28 moves vertically in the tubular member 26, the cross member 34 may also move vertically in the slot 32.

The column assembly 20 is similar to the column assembly 18, such that it is provided with a slot similar to the slot 32 in such slot and move up and down with the respective hollow tubular member 28 of the

assemblies

18 and 20.

Interconnecting upper ends of the hollow tubular members 28 of the

assemblies

18 and 20 is a secondcro'ss member 38 which may, at its opposite ends, be welded to the hollow tubular members 28 of the

assemblies

18 and 20, respectively.

A third cross member 40 is welded at its opposite "ends to upstanding portions of the hollow tubular members 30 of the

assemblies

18 and 20 at locations above the uppermost end portions of the hollow tubular members 28.

The structural interconnection'of the pair of column assemblies 22 and 24 is similar to that disclosed in connection with the pair of column assemblies 18 and'=20, such that there are

respective cross members

34, 38 and 40 interconnecting both pairs of column assemblies. Thus, a cross member 40 interconnecting upper ends of the tubular members 30 of each pair of column assemblies are disposed at

opposite ends

10 and 12 of the scaffold, as shown in FIG. 9. Thus, the cross member 40 at

opposite ends

10 and 12 support planks 42 thereon. These planks 42' are secured together at their lower sides by stops 44 or each plank 42 may have a pair of individual stops disposed adjacent the cross members 40, such that the planks may not slide longitudinally an appreciable distance between the cross members 40. In this manner, these stops 44 retain the planks 42 when they are'moved into broken line inclined positions, disclosed in FIG. 8 of the drawings.

'The hollow tubular members-26 of the column assem blies 20 and 24 are interconnected by

diagonal braces

44 and 46. These braces may be welded to the hollow tubular members 26 or they may be removably bolted thereto or removably connected thereto in any suitable manner, as desired. Removable connections of the

braces

44 and 46 with the hollow tubular members 26 will permit the scaffold structure of the invention to be disassembled so thatthe pairs of

column assemblies

18 and 20 with their inter-'- connecting

cross members

34, 38 and 40 may be removably secured to the pair of columnassemblies 22 and 24* together with their

cross members

34, 38 and 40.

Diagonal braces

48 and 50 interconnect the-tubular members 28 of the

column assemblies

20 and 24 and also the assemblies 18 and 22 at-opposite sides of the scaffold. Lower end portins'52 and 54 of the braces '48-and 50,- respectively, are connected'to the cross bars 34 while upper members 38, as shown best in FIGS. 4 and of the drawings. The connection of each'upper end 56 and 60 of the

braces

48 and 50, respectively, is preferably at the upper end of each tubular member 28 above the upper end of the respective tube 26. These

brace members

48 and 50 may. be-welded in their connections with the cross members 34 and the upper portions of the tubularmembers 28 or they may be 'bolted or otherwise removably connected to provide for disassembly of thescaffold into separate brace components and pairs of column assemblies at the ends and 12 of the scaffold to thereby permit complete collapsing of the scaffold to render it readily portable. It will be seen that the planks 42 may readily be removed from the cross member '40'to accommodate disassembly of the scaffold structure, if desired.

Pressure fluid operated

hydraulic cylinders

62, 64, 66

and 68 are disposed to elevate the scaffold structure of the invention, the hydraulic cylinder 62 .being provided with a plunger 63 secured at 70 by a bracket welded to a cross bar 72 having its opposite ends welded or otherwise fixed to the tubularmember 26 of the

column assemblies

18 and 20. A normally upper end of the hydraulic cylinder 62 is mounted on a pin 74 carried by a bracket 76 secured by welding or otherwise to the respective cross member 38, as shown best in FIG. 5 of the drawings.

The hydraulic cylinder 64 is provided with a plunger 78 mounted by a pin 80 to a bracket 82 fixed to the cross bar 34. The cylinder 64 is mounted by means of a pin 84 to a bracket 86 and this bracket 86 is welded or otherwise secured to the respective cross bar 40.

' Extension of the plunger 63 from the cylinder 62 causes the telescopic elevation of the tube 28 relative to the respective tube 26 and energization of the cylinder 64 to extend its plunger 78 causes the cylinder to raise the tubular telescopic element 30 relative to the tubular telescopic element 28 of each column assembly. It will be seen that the hydraulic cylinder 66 is structurally arranged in an equivalent manner to that of the hydraulic cylinder of the

hydraulic cylinders

64 and 66 may permit the scatfold planks 42 to be disposed on an incline, as indicated by broken lines in FIGS. 4 and 8 of the drawings, simply by independently energizing one of the cylinders 64 and E 66 to a greater degree than the other from an elevational standpoint.

As shown in FIG. 1 of the drawings, the

hydraulic cylinders

62 and 64 are disposed at a location substantially intermediate the

column assemblies

18 and 20 and, likewise, the

cylinders

66 and 68 are in a similar location between the pair of column assemblies 22 and 24.

The cylinder 62, as hereinbefore described, is supported by means of a bracket carried by the cross bar 72 and this cross bar 72 is braced near its intermediate portion adjacent the bracket 70 by means of diagonal braces and 82 having their upper end portions welded at 84 to the respective outer tubular member 26 of the respective column assembly, all as shown best in FIGS. 1 and 5 of the drawings.

Interconnecting the respective tubular member 26 of the

column assemblies

18 and 20 and also the column assemblies 22 and 24, respectively, is a cross member 86 which is welded or otherwise secured to the tubular member 26 adjacent the connections 84 of the diagonal 20. Thus, vertical loading and stress applied by operation ends 56 and "60 of the braces 48'and 50 are connected to] upper end portions of the hollow tubular members 28near 7 diagonally disposed relative to the connection of the of the hydraulic cylinder 62 is carried by the

braces

80 and 82 together with the cross member 72 and the cross member 86, as hereinbefore described.

As shown in FIG. 1, it will be seen that the bracket members 86, as hereinbefore described, are substantially upper end of the cylinder 64 therewith at 65, as shown in FIG. 5 of the drawings.

As shown in FIGS. 1, 3, 4 and 5 of the drawings, each of the

column assemblies

18, 20, 22 and 24 may be supported on a suitable caster 88 to facilitate movement of the scaffold of, the invention.

Carried on

plates

90 and 100 secured to upper ends of the tubular members 80 of the

column assemblies

20 and 24 are

valves

102 and 104. These

valves

102 and 104 are provided with control arms for actuating valve elements to control operation of the

respective cylinders

62, 64, 66 and 68. The valve 102 is provided with two operating

handles

106 and 108, while the valve 104 is provided with a pair of operating handles 110 and 112, as will be hereinafter described in detail, in connection with the diagrammatic view of the hydraulic system, shown in FIG. 2.

A motor driven pump 114 is mounted in connection with the cross member 72, hereinbefore described, and this motorized pump is adapted to supply pressure fluid through the

valves

102 and 104 to the

hydraulic cylinders

62, 64, 66 and 68, all as shown best in FIG. 2 0f the drawings. These

cylinders

62, 64, 66 and 68 are double acting cylinders controlled 'by the operating handles 106, 107, 110 and 112, respectively, of the

valves

102 and 104, hereinbefore described. An outlet conduit 116 from the pump 114 delivers fluid through a spring loaded bypass valve 118 which is adapted to bypass fluid into a reservoir 120, when fluid is not permited to flow into one of the

cylinders

62, 64, 66 or 68. An inlet conduit 122 communicates with the inlet of the pump and extends downwardly into a lower portion of the reservoir 120.

A hydraulic return line 124 is coupled to

individual return lines

126, 128, 130 and 132 communicating with the

cylinders

62, 64, 66 and 68, respectively.

It will be understood that the valve operating handles 106 and 112 may be suitably coupled so that both the

cylinders

62 and 68 may be energized at the same time while the operating handles 108 and 110 may also be coupled for concurrent operation so that the

cylinders

64 and 66 may be operated concurrently. Additionally, it will be seen that each of the

handles

108 and 110 may be operated individually to obtain individual height adjustment, as indicated in FIG. 8 of the drawings and hereinbefore described, in order to place the platform planks 42 on an incline relative to the horizontal.

The coupling of the valves, as hereinbefore described, may be done electrically and these valves may be solenoid valves so that selective operation of these valves may be attained and also it will be understood that concurrent operation of these valves may be attained, if desired, particularly the valves controlling the

cylinders

62 and 68 should be operated together while, in most instances, the valves controlling the

cylinders

64 and 66 should be operated concurrently. The

cylinders

64 and 66 should only be energized independently, when it is desired to obtain an incline of the plank deck 42 relative to the horizontal after the platform has been substantially elevated to its desired disposition.

As. shown in FIGS. 10, 11 and 12 of the drawings, the modified structure of the invention is provided with four

column assemblies

140, 142, 144 and 146 located similarly to the

column assemblies

18, 20, 22 and 24, hereinbefore described.

Each

column assembly

140, 142, 144 and 146 is similar and these column assemblies are in pairs at opposite ends of the scaffold, as for example, the

column assemblies

140 and 142 form one pair, while the column assemblies 144 and 146 form another pair, all as shown best in FIGS. 10, 11 and 12.

Inasmuch as all of the corner assemblies are substantially identical in structure, the

corner assemblies

142 and 146 will be described generally, as shown in the drawings.

As shown in FIGS. 1 and 2, the corner assembly 142 is provided with a pair of substantially vertical external hollow

cylindrical column members

148 and 149. Telescopically supported in these hollow cylindrical members '148 and 149 are

internal column members

150 and 152, respectively. The internal column member 150 being extendable upwardly and retractable downwardly relative to the interior of the hollow cylindrical column member 148, while the column member 152 is extendable downwardly and retractable upwardly within the hollow cylindrical column member 149.

Mounted on a lower end of the internal column member 152 is a caster 154 and extendably mounted telescopically in an upper end 156 of the internal column member 150 is an uppermost column member 158.

Secured to an upper end portion of the uppermost column member 158 is a cross member 160, the opposite end of which is carried by a similar uppermost column member 162 telescopically extendable upwardly from an internal column member 164 which is telescopically mounted in a hollow cylindrical column member 166 of the column assembly 140. The same combination of mechanism exists with respect to said pair of column assemblies 144 and 146.

Planks 168 form a platform extending across the cross members and a plunger 170 of a hydraulic cylinder 172 is connected to an intermediate portion 174 of the cross member 160 by a clevis 176 reinforced by

braces

178 and 180. The body or cylinder portion of the hydraulic cylinder 172 at its upper end is connected to a cross member 182 having its opposite ends supported on the

internal column members

150 and 164. This is the general construction of each pair of column assemblies and the respective scaffold structural elements. The cylinder 172 being operable independently of a cylinder 184 disposed in a similar manner between the column assemblies 144 and 146 at their uppermost column members which correspond with the

column members

162 and 158.

A pair of

hydraulic cylinders

186 and 188 are secured together and supported by

cross members

190 and 192 at respective upper and lower ends of the hollow

cylindrical members

166 and 149 of the

column assemblies

140 and 142. Thus, the

cylinders

186 and 118 are fixed to the

column assemblies

140 and 142. The cylinder 188 has an upwardly extendable and downwardly retractable plunger 191 having a clevis connection 193 secured to the cross bar 182 at normally upper ends of the

internal column members

150 and 164. The hydraulic cylinder 186 has a downwardly extendable and upwardly retractable plunger 194 pivotally connected to a clevis 196 carried by a cross member 198 having its opposite ends secured to the downwardly extending internal column member 152 and a similar downwardly extending internal column member 200 which is extendable downwardly from the column assembly 140 in a similar manner to the telescopically extendable relationship of the internal column member 152.

A hydraulic pressure fluid supply system 202 is carried on a cross member 198 and adapted to clear the hollow

cylindrical column members

148 and 149, when the internal column member 152 is in retracted position relative to the hollow cylindrical member 149. This hydraulic system 202 is similar to that shown in FIG. 2 and is adapted, when energized, to provide pressure fluid to the

hydraulic cylinders

172, 186 and 188, as desired, either collectively or selectively such as to extend the scaffold structure of the invention vertically and to permit independent energization of the

cylinders

172 and 184, such that the planks 168 may be disposed, as indicated by broken lines 169, to place the scaffold platform on an incline, as desired.

It will be seen that the hollow cylindrical column memher 148 of the column assembly 142 is disposed inwardly with respect to the hollow cylindrical column member 149 from a respective end of the scaffold of the invention. Likewise, all the

other column assemblies

140, 144 and 146 are similar.

A cross brace 204, as shown in FIG. 10 of the drawings, is pivotally connected at 206 to a lower portion of the internal column member 152 and an opposite end of the brace 204 is pivotally connected at 206 with a member which traverses a slot in the cylindrical member 252, as will be hereinafter described. This cylindrical member corresponding to the hollow cylindrical member 149 of the column assembly 142. Likewise, another similar cross brace 208 is. pivoted at its lower end 210 to another of the internal column members 212 extendable downwardly from the column assembly 146. The opposite end of the brace 208 is pivotally connected at 214 to a member which traverses a slot in the hollow cylindrical column member 149, as will be hereinafter described. Inwardly relative to the

braces

204 and 208 are

braces

216 and 218, these braces being shown in plan section in FIG. 13.

It will be seen that the

braces

216 and 218 at their lower ends pivotally interconnect innermost hollow cylindrical members at the corner assemblies, said innermost cylinders being comparable to the hollow cylindrical column member 148. The lower ends of the

braces

216 and 218 pivotally interconnect lower ends of these hollow cylindrical column members, while upper ends of the braces, in a cross position interconnect upper ends of the hollow cylindrical column members similar to the inner ones 142 or a comparable inner cylindrical member 220, shown in FIG. 3, which forms an element of the column assembly 146.

Additional cross braces 222 and 224 at their lower ends are connected to members which traverse slots in the innermost hollow

cylindrical members

148 and 220, as will be hereinafter described.

Disposed on upper opposite ends of the scaffold of the invention, as shown in FIG. 10, are

control assemblies

228 and 230 similar to the

assemblies

100 and 102, shown in FIG. 4 of the drawings.

It will be seen from FIG. 11, that

diagonal braces

232 and 234 are connected to the cross member 198 near the clevis 196 and that upper opposite ends of the

braces

232 and 234 are extended angularly outward and are pivotally connected to the upper ends of the

braces

204 and 208. In this manner, the sides and the ends of the scaffold are braced so as to transfer through the

diagonal braces

232 and 234 forces imposed by the cylinder plunger 194 and to assist the cross member 198 in supporting this load. In a similar manner, braces 236 and 238 are connected to the cross member 182 and downwardly and outwardly extending

portions

240 and 242 of these

braces

236 and 238 are pivotally connected to the lower ends of the

braces

222 and 224. Accordingly, load from the plunger 198 is carried partly in tension by the

braces

240 and 242 transferred to the

diagonal braces

222 and 224 and also the

braces

216 and 218.

As shown in FIG. 13, it will be seen that the

braces

204 and 208 at their connections 206 are secured to an angle member 248 which is connected to a bar 250 secured to the internal column member 212. The bar 250 operating vertically in a vertical slot 251 disposed in the hollow cylindrical column member 252 which is similar to the hollow cylindrical column member 149. A similar arrangement exists with respect to the

braces

222 and 224 and the

diagonals

236 and 238 and with respect to the hollow

cylindrical column members

148 and 220, such that the upwardly extending internal column members 150 may retract downwardly vertically into the hollow cylindrical column members 148 and permit the

braces

222 and 224 connected to a bar 225 to traverse a slot 221 in the cylindrical member 220 to move downwardly together with the internal column members 150 and the

diagonals

236 and 238. Thus, all of the corner assemblies are constructed.

It will be obvious to those skilled in the art that various modifications of the present invention may be resorted to in a manner limited only by a just interpretation of the following claims.

I claim:

1. In a scaffold the combination of: a generally rectangular scaffold structure having four corners and first and second ends; four vertically extendable telescopic column assemblies; each of said column assemblies disposed at one of said four corners; a first pair of said column assembiles disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at said second end of said scaffold structure; first means coupled to said first pair of telescopic column members and disposed to extend said first pair vertically; second means coupled to said second pair of vertically extendable column members and disposed to extend said second pair vertically and independently relative to said first pair, whereby each of said pair may be independently extended to an elevation different from that of the other pair; and deck means abridging and supported by said first and second pairs of column members, whereby said deck means may be supported on an incline relative to the horizontal when one of said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of the other pair of column members; first and second relatively movable sections of each of said assemblies; cross bars interconnecting said first and second sections, respectively, of each of said pairs of assemblies; said first means extendable and interconnecting said cross bars of said first and second sections, respectively, at locations substantially midway between the column assemblies of each pair of column assemblies.

2. In a scaffold the combination of: a generally rectangular scaffold structure having four corners and first and second ends; four vertically extendable telescopic column assemblies; each of said column assemblies disposed at oneof said four corners; a first pair of said column assemblies disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at said second end of said scaffold structure; first means coupled to said first pair of telescopic column members and disposed to extend said first pair vertically; second means coupled to said second pair of vertically extendable column members and disposed to extend said second pair vertically and independently relative to said first pair, whereby each of said pair may be independently extended to an elevation different from that of the other pair; and deck means abridging and supported by said first and second pairs of column members, whereby said deck means may be supported on an incline relative to the horizontal when one of said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of the other pair of column members; first and second relatively movable sections of each of said assemblies; cross bars interconnecting said first and second sections, respectively, of each of said pairs of assemblies; said first means extendable and interconmeeting said cross bars of said first and second sections, respectively, at locations substantially midway between the column assemblies of each pair of column assemblies; said first means being a hydraulic cylinder and plunger actuator.

3. In a scaffold the combination of: a generally rectangular scaffold structure having four corners and first and second ends; four vertically extendable telescopic column assemblies; each of said column assemblies disposed at one of said four corners; a first pair of said column assemblies disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at said second end of said scaffold structure; first means coupled to said first pair of telescopic column members and disposed to extend said first pair vertically; second means coupled to said second pair of vertically extendable column members and disposed to extend said second pair vertically and independently relative to said first pair, whereby each of said pair may be independent? ly,,ex tended .to an elevation different from that off the other pair; and .deck means abridgingand supported by said first and second pairs of column members whereby said deck means may be supported on an incline relative to the horizontal when oneof said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of'the other pair of column members;..first, and .secondrelati'vely movable sections of each-of saidassemblies; cross bars interconnecting said first and second sections, respectively, of each of" said pairs of assemblies; said first means extendable and interconnecting .said. cross bars of said first and second sections, respectively, at locations substantially midway between the column assembliesof each pair of columnvas: semblies; said first sections of each column assembly being hollow and containing said second section, each of said first sections having a vertically disposed slotted side wall through which cross bars, connecting said respective second sections, extend.

4. In a scaffold the combination of: a generally rectangular scaffold structure having four corners and first and second ends; four vertically extendable telescopic column assemblies; each of said column assemblies dis posed at one of said four corners; a first pair of said column assemblies disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at said second end of said scaffold structure; first means coupled to said first pair of telescopic column members and disposed to extend said first pair vertically; second means coupled to said second pair of vertically extendably column members and disposed to extend said second pair vertically and independently relative to said first pair, whereby each of said pair may be independently extended to an elevation different from that of the other pair; and deck means abridging and supported by said first and second pairs of column members, whereby said deck means may be supported on an incline relative to the horizontal when one of said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of the other pair of column members; each of said column assemblies comprising three concentric relatively telescopic sections; brace means interconnecting said telescopic sections; vertically slotted portions of some of said sections disposed and receiving said brace means interconnecting some of the other telescopic sections of each column assembly.

5. In a scaffold the combination of: a generally rectangular scaffold structure having four comers and first and second ends; four vertically extendable telescopic column assemblies; each of said column assemblies disposed at one of said four corners; a first pair of said column assemblies disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at said second end of said scaffold structure; first means coupled to said first pair of telescopic column members and disposed to extend said first pair vertically; second means coupled to said second pair of vertically extendable column members and disposed to extend said second pair of vertically and independently relative to said first pair, whereby each of said pair may be independently extended to an elevation different from that of the other pair; and deck means abridging and supported by said first and second pairs of column members, whereby said deck means may be supported on an incline relative to the horizontal when one of said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of the other pair of column members; first and second relatively movable sections of each of said assemblies; cross bars interconnecting said first and second sections, respectively, of each of said pairs of assemblies; said first means extendable and interconnecting said cross bars of said first and second sections, respectively, at locations substantially midway between the column assemblies of each pair of column assemblies; said first sections of each column assembly being hollow and containing said second section, each of said first sections having a vertically disposed slotted side wall through which cross bars, connecting said respective second sections,extend; braces interconnecting said first and second pairs of column assemblies at said first and second ends, respectively, of said scaffold structure, t

6. In a scaffold the combination of: a generally, rec tangular scaffold structure having four corners and first and secondends; tour vertically extendable telescopic column assemblies; each of said column assemblies disposed at one of said four corners; a first pair of said column assemblies disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at saidsecond end of said scaffold structure; first hydraulic cylinder 'means coupled to said first pair of telescopic column members and disposed to extend said first pair vertically; second hydraulic cylinder means coupled to said second pair of vertically extendable column members and disposed to extend said second pair vertically and independently relative to said first pair, whereby each of said pairs may be independently extended to an elevation different from that of the other pair; and deck means abridging and supported by said first and second pairs of column members, whereby said deck means may be supported on an incline relative to the horizontal when one of said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of the other pair of column members; motor and pump means carried by said scaffold structure and disposed to deliver hydraulic pressure fluid to said hydraulic cylinders.

7. In a scaffold the combination of: a generally rectangular scaffold structure having four corners and first and second ends; four vertically extendable telescopic column assemblies; each of said column assemblies disposed at one of said four corners; a first pair of said column assemblies disposed at said first end of said scaffold structure; a second pair of said column assemblies disposed at said second end of said scaffold structure; and cross angular brace means interconnecting said column assemblies at said sides and ends of said scaffold; first means coupled to said first pair of telescopic column members and dispose-d to extend said first pair vertically; second means coupled to said second pair of vertically extendable column members and disposed to extend said second pair vertically and independently relative to said first pair whereby each of said pair may be independently extended to an elevation different from that of the other pair; and deck means abridging and supported by said first and second pairs of column members, whereby said deck means may be supported on an incline relative to the horizontal when one of said pairs of column assemblies is telescopically extended and disposed at an elevation different from that of the other pair of column members; each column assembly comprises first and second external hollow cylindrical column members disposed vertically and parallel to each other and fixed in contiguous relationship to each other, said hollow cylindrical column members having upper and lower ends; first and second internal column members telescopically slidably mounted in said first and second external cylindrical members, respectively, said first internal column members telescopically extendable upwardly from an upper end of said first external cylindrical members and said second external column members telescopically extendable downwardly from a lower end of said second external column members.

8. The invention, as defined in claim 7, wherein: said first and second means each comprising first and second power operated actuators fixed respectively to said first and second external hollow cylindrical column members; power operated extendable and retractable members for said actuators, said first actuators having their said extendable members extendable upwardly and retractable downwardly, said first actuator having its extendable member connected to said first internal column members of a respective pair of said column assemblies; said second I actuators having their said extendable members extendable downwardly and retractable upwardly, said second actuators having their extendable members connected to said second internal column members of a respective pair of said column assemblies.

9. The invention, as defined in claim 8, wherein: each of said first hollow cylindrical column members is disposed inwardly *from a respective end of said scaffold with respect to respective ones of said hollow cylindrical column members.

10. The invention, as defined in claim 8, wherein: uppermost telescopic members are upwardly extendably mounted on said first internal column members and said first r e A 7 each of said pairs of internal column members and disposed to vertically extend upward and retract downwardly to move said uppermost telescopic members relative to said first internal column members.

References Cited UNITED STATES PATENTS 2,657,009 10/1953 Neis 254-93 2,692,169 10/1954 Phillips 182141 2,993,561 7/1961 Watson 182-195 3,017,968 1/1962 McMahon 182141 3,028,928 4/1962 Iuculano 182-178 and second means also comprising actuating means on 5 REINALDO P. MACHADO, Primary Examiner.