US3891055A

US3891055A - Self-elevating scaffold construction

Info

Publication number: US3891055A
Application number: US425775A
Authority: US
Inventors: Alfred A Medlock
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-12-18
Filing date: 1973-12-18
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24

Abstract

A pair of upstanding end frames are provided and each end frame includes upper and lower sections guidingly supported from each other for relative vertical movement. The upper sections of the frames include scaffold board support portions and motor structure is operatively connected between the upper and lower sections of each end frame whereby the upper section may be raised and lowered relative to the lower section. The upper and lower sections of each frame further include support portions for removable support from the end section cross members of conventional scaffold frames.

Description

Unite States Medlock atet 1 1 June 24, 1975 SELF-ELEVATING SCAF FOLD CONSTRUCTION Alfred A. Medlock, PO. Box 627, Ocean Springs, Miss. 39564 Filed: Dec. 18, 1973 Appl. No.: 425,775

Inventor:

us. c1 182/141; 182/132 1111. c1. E04g l/l8 Field of Search 182/178, 141, 148, 63,

References Cited UNITED STATES PATENTS 8/1958 Esch 182/141 5/1963 Casella 182/129 12/1965 Brayton 182/178 3,385,400 5/1968 Whitsett 182/179 3,717,220 2/1973 Donker 182/129 FOREIGN PATENTS OR APPLICATIONS 1,430,237 1/1966 France 182/141 Primary Examiner-Reinaldo P. Machado Attorney, Agent, or FirmClarence A. OBrien; Harvey B. Jacobson 12 Claims, 5 Drawing Figures SELF-ELEVATING SCAFFOLD CONSTRUCTION BACKGROUND OF THE INVENTION Conventional scaffold frames are used for many purposes in the construction industry. Quite often these scaffold frames are utilized initially to form a low support for workmen in construction of a wall and as the wall being constructed increases in height additional scaffold sections are added on top of the initial scaffold section. However, conventional scaffold sections include scaffold board supports which are not adjustable in height and a workman constructing a wall through the utilization of conventional scaffolding must perform his work on the wall at various elevations in relation to the portion of the scaffolding upon which he is standing. Thus, the workman will sometimes be working at a level only slightly elevated relative to his feet and at other times be working at an elevation which may be shoulder height or higher. In addition, the scaffolding boards upon which the workman is supported as well as the scaffolding boards upon which his work materials are supported must occasionally be repositioned in height relative to the scaffold section being used.

SUMMARY OF THE INVENTION The scaffold construction includes end frames each consisting of upper and lower sections which may be raised and lowered relative to each other. The upper sections may be provided with crossed bracing and the upper sections include scaffold board support portions between which scaffolding boards may extend and be supported. In this manner. the scaffold boards supporting a workman and his work materials may be adjustably raised relative to the lower sections of the end frames as the upper sections of the end frames are raised relative to the lower sections. In addition the upper and lower sections include support portions for removable support from the end section cross members of conventional scaffold frames and in this manner if the maximum desired elevation of the scaffold construction is greater than that which may be achieved with the lower sections of the end frames resting on the ground, after the upper sections have been elevated relative to their lower sections almost to their limits of elevation conventional scaffolding construction may be erected between the end frames and the support portions on the upper sections may be lowered into engagement with the erected conventional scaffolding for support therefrom. Then, the lower sections of the end frames may be raised relative to the upper sections and have their support portions engaged with upper cross members of the conventional scaffolding for support therefrom whereby the upper sections of the end frames may again be raised relative to the lower sections in order to further elevate the scaffolding boards supported therefrom.

The main object of this invention is to provide a scaffolding construction which will enable workmen and their materials to be supported at the most advantageous elevation relative to the work being performed by the workmen.

Another object of this invention, in accordance with the immediately preceding object, is to provide a scaffolding construction for supporting the' scaffold boards comprising the support for workmen and materials to be used by the workmen in a manner such that the boards may be gradually elevated as the elevation of the work being performed by the workmen increases in height.

Yet another object of this invention is to provide a scaffolding construction which may be utilized efficiently in the erection of and dismantling of conventional scaffolding structures.

A final object of this invention to be specifically enumerated herein is to provide a scaffolding construction in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble-free in operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the scaffolding construction of the instant invention in operative association with a conventional scaffolding structure;

FIG. 2 is an enlarged fragmentary vertical sectional view illustrating the manner in which the upper and lower sections of the scaffolding construction are supported from each other for relative vertical movement;

FIG. 3 is a horizontal sectional view taken substantially upon the plane indicated by the section line 33 of FIG. 2;

FIG. 4 is a vertical sectional view taken substantially upon the plane indicated by the section line 4-4 of FIG. 3; and

FIG. 5 is an enlarged fragmentary vertical sectional view taken substantially upon the plane indicated by the section line 55 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT The numeral 10 generally designates a conventional form of scaffolding including a pair of upright end sections 12 interconnected by means of

crossed bracing members

14 and 16. Each of the end sections 12 includes a pair of

uprights

18 and 20 interconnected by means of vertically spaced

horizontal cross members

22, 24, 26 and 28. The

uprights

18 and 20 are tubular and the lower ends thereof are provided with removable feet 30 while the upper ends thereof are open and project slightly above the corresponding cross members 22.

The conventional scaffolding 10 may be erected in vertically stacked relation with several scaffolding structures stacked on top of each other and suitable connecting members telescoped within and secured between opposing upper and lower ends of theuprights 18 of the stacked scaffolding sections. Further, suitable scaffolding boards may extend between and be supported from the upper cross members 22. Accordingly, it will be appreciated that scaffolding boards may be placed at spaced elevations throughout the height of a plurality of stacked scaffold constructions 10.

However, the scaffolding boards may not be positioned at precise elevations nor may they be gradually increased in elevation as a wall being constructed by a bricklayer or the like increases in height. Thus, although at one point in the construction of a wall the elevation of work may be ideal in relation to the elevation of the workman, the workman must also work at an elevation requiring him to bend over and at other elevations requiring him to work at an elevation of perhaps shoulder height.

The self-elevating scaffold construction of the instant invention is referred to in general by the reference numeral 34 and includes a pair of end frames referred to in general by the reference numerals 36. Each of the end frames 36 includes an upper section referred to in general by the reference numeral 38 and a lower section referred to in general by the reference numeral 40.

Each lower section 40 comprises a horizontal base member 42 from which a pair of spaced upright tubular members 44 are supported. The upper ends of the tubular members 44 are interconnected by means of a transverse header member 46 and each upper section 38 includes a pair of upstanding tubular members 48 which are slidingly telescoped over the tubular members 44 and are interconnected at their upper ends by means of a transverse member 50 extending therebetween.

Vertically intermediate portions of the tubular members 48 are interconnected by means of horizontally disposed U-shaped braces 52 for supporting center scaffolding boards 54 and the lower ends of the tubular members 48 are interconnected by means of a lower transverse portion 56 and the opposite ends of the transverse portions 56 project outwardly beyond remote sides of the tubular members 48 and include depending shank portions 58 which are telescopingly receivable downwardly in the upper ends of the uprights 18 and of the conventional scaffolding 10.

Each of the lower brace members 42 supports the lower end of an upstanding cylinder portion 60 of a fluid motor 62 therefrom and each fluid motor 62 includes an extendable piston rod portion 64 which is carried by a piston 66 slidable in the cylinder portion 60. The piston rod portion 64 is extendable through a central opening 68 formed in the upper end wall 70 of the cylinder portion 60 and the upper end wall 70 as well as the lower end wall 72 of the cylinder portion 60 has a fluid inlet and outlet fitting 74 secured therethrough by which fluid under pressure may be admitted into either the upper or lower end of the cylinder portion 60 and vented from the other end.

The upper end of the piston rod portion 64 is anchored to the center of the transverse member 50.

Three sides of each tubular member 48 include rol lers 76 journaled therefrom and the rollers 76 are dis posed in rolling contact with the outer surfaces of the corresponding sides of the associated inner tubular members 44. Also, the fourth side of each tubular member 48 includes a pivoted pawl 78 and the pawl 78 is operable through an opening 80 provided therefor in the fourth side of the tubular member 48.and engageable with longitudinally extending rack gear teeth 82 formed on the outer surface of the corresponding wall of the inner tubular member 44. The pawls 78 and the rack gear teeth 82 are provided to prevent uncontrolled dropping of the tubular members 48 along the tubular members 44.

From FIGS. 1, 3 and 4 of the drawings it may be seen that each of the transverse base members 42 has a pair of opposite end inclined sleeves 86 supported therefrom and that each sleeve 86 has a forked slide 90 slidably disposed therein. A locking pin 92 is supported from each sleeve 86 and is selectively engageable in a pair of apertures 94 spaced therealong. Each locking pin 92 is projectable through the apertures 94 and into a similar aperture (not shown) formed in the corresponding slide 90 whereby the slide 90 may be locked in the projected position illustrated in FIG 4 of the drawings or in a retracted position with the forked end of the slide 90 substantially fully received within the sleeve 86. The forked end of each slide 90 is engageable with the corresponding transverse member 28 in the manner illustrated in FIG. 4 of the drawing or the corresponding upper transverse member 22. Accordingly, it may be seen that the base member 42 may be supported from the scaffolding end section 12 either at a low elevation adjacent the low transverse brace member 28 or at an upper elevation adjacent the upper transverse brace member 22.

The upper sections 38 may be provided with crossed bracing (not shown) such as the

cross bracing members

14 and 16. Also, scaffolding boards 96 may extend between and be supported from the transverse portions 56 and the latter may be provided with sockets (not shown) for supporting a railing structure 98.

In operation, the end frames 36 may be positioned as desired and the tubular members 48 may be provided with cross bracing members such as the

cross bracing members

14 and 16. Then, the upper sections 38 may be raised relative to the lower sections 40 by extension of the piston rod portions 64. Of course, the

boards

54 and 96 will be elevated with the upper sections 38.

If it is desired to support workmen and their materials at a higher elevation, after the upper sections 38 have been substantially fully raised, the conventional scaffolding 10 may be erected in the manner illustrated in FIG. 1 of the drawings and the upper sections 38 may be further raised so that the upper ends of the conventional scaffolding uprights l8 and 20 may be positioned immediately beneath the shank portions 58. Then, the upper sections 38 may be lowered to telescope the shank portions 58 downwardly into the upper ends of the uprights l8 and 20 to thus support the upper sections 38 from the end sections 12. Thereafter, fluid under pressure may be pumped into the upper ends of the cylinder portions to raise the lower base members 42 from the ground, past the positions thereof illustrated in FIGS. 1 and 4 of the drawings and to eleva tions closely adjacent the upper transverse brace members 22 so that the slides may be extended from the sleeves 86 in order to engage the opposite ends of the upper transverse brace members 22 in the manner in which the slides 90 are engaged with the opposite ends of the lower transverse brace members 28 in FIGS. 1 and 4 of the drawings. After the slides 90 have been extended and locked in position by means of the lockpins 92 so that the lower sections 40 are supported from the opposite ends of the upper transverse brace members 22, fluid under pressure may be pumped into the lower ends of the cylinder portions 60 to raise the upper sections 38 relative to the upper portions of the conventional scaffolding 10. Of course. this process may be repeated so that additional conventional scaffolding structures may be stacked on top of the conventional scaffold structure 10 and the scaffolding construction 34 may be actuated to lift itself up along the stacked conventional scaffolding constructions l0.

Further. the motors 62 may be replaced by electric motor powered or manually powered screw jacks. Also. the sections 38 may be raised by means of lift cables wound on manually or electrically actuated winding members.

The foregoing is considered illustrative only of the principles of the invention. Further. since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. A scaffold construction including a pair of end frames each having upper and lower sections guidingly supported from each other for relative vertical shifting, motor means connected between said upper and lower sections for shifting the latter relative to each other, scaffold board support means carried by said upper sections for supporting the opposite ends of boards extending therebetween, said upper and lower sections including anchor structure for releasable engagement with and support from upper and lower portions of adjacent conventional scaffold end sections, the anchor structure of said lower sections also being provided for releasable engagement with and support from upper portions of adjacent conventional scaffold end sec tions.

2. The combination of claim 1 wherein said motor means includes an upright fluid cylinder having its upper and lower ends connected to said upper and lower sections, respectively.

3. The combination of claim 2 wherein said fluid cylinder is of the double acting type.

4. A scaffold construction including a pair of end frames each having upper and lower sections guidingly supported from each other for relative vertical shifting, motor means connected between said upper and lower sections for shifting the latter relative to each other, scaffold board support means carried by said upper sections for supporting the opposite ends of boards extending therebetween, each of said lower sections including a lower horizontal member and a pair of first uprights supported at their lower ends from spaced portions of said horizontal member and interconnected at their upper ends by means ofa cross member extending therebetween, each of said upper sections including a pair of spaced and interconnected second upstanding tubular uprights telescoped over said first uprights, said scaffold board support means comprising portions of vertically spaced brace means extending between and secured to said tubular uprights.

5. The combination of claim 3 wherein said motor means including an upright fluid cylinder having its upper and lower ends connected to said upper and lower sections, respectively.

6. The combination of claim 5 wherein said fluid cylinder is of the double acting type.

7. The combination of claim 4 wherein said first pair of uprights including longitudinally extending rack teeth and said second pair of uprights including pivoted stop dogs engageable with said teeth in ratchet fashion for preventing uncontrolled dropping of said second uprights relative to said first uprights in the event of failure of said motor means.

8. The combination of claim 7 wherein said upper and lower sections include anchor structure for releasable engagement with and support from upper and lower portions of adjacent conventional scaffold end sections, the anchor structure of said lower sections also being provided for releasable engagement with and support from upper portions of adjacent conventional scaffold end sections.

9. The combination of claim 8 wherein said motor means includes an upright fluid cylinder having its upper and lower ends connected to said upper and lower sections, respectively.

10. The combination of claim 9 wherein said fluid cylinder is of the double acting type.

11. A scaffold construction including a pair of end frames each having upper and lower sections guidingly supported from each other for relative vertical shifting, motor means connected between said upper and lower sections for shifting the latter relative to each other, scaffold board support means carried by said upper sections for supporting the opposite ends of boards extending therebetween, each of said lower sections including a lower elongated horizontal member and a pair of first uprights supported at their lower end portions from longitudinally spaced portions of said horizontal member spaced inwardly of the opposite ends of said horizontal member, each of said upper sections including a pair of spaced uprights guidingly engaged with said first uprights and interconnected at their lower end portions by means of a second lower elongated horizontal member to which the lower end portions of said second uprights are secured at portions spaced therealong and inwardly from the opposite ends of said second horizontal member, the opposite end portions of the horizontal member of said upper section, outwardly of the corresponding uprights, including anchor structure for releasable engagement with and support from the upper portions of adjacent conventional scaffold end sections, the opposite end portions of the horizontal member of the lower section, outwardly of the corresponding uprights, including anchor structure for releasable engagement with and support from the upper and lower portions of adjacent conventional scaffold end sections.

12. The combination of claim 11 wherein said motor means includes an upright fluid cylinder having its upper and lower ends connected to said upper and lower sections, respectively, said fluid cylinder being of

Claims

1. A scaffold construction including a pair of end frames each having upper and lower sections guidingly supported from each other for relative vertical shifting, motor means connected between said upper and lower sections for shifting the latter relative to each other, scaffold board support means carried by said upper sections for supporting the opposite ends of boards extending therebetween, said upper and lower sections including anchor structure for releasable engagement with and support from upper and lower portions of adjacent conventional scaffold end sections, the anchor structure of said lower sections also being provided for releasable engagement with and support from upper portions of adjacent conventional scaffold end sections.

4. A scaffold construction including a pair of end frames each having upper and lower sections guidingly supported from each other for relative vertical shifting, motor means connected between said upper and lower sections for shifting the latter relative to each other, scaffold board support means carried by said upper sections for supporting the opposite ends of boards extending therebetween, each of said lower sections including a lower horizontal member and a pair of first uprights supported at their lower ends from spaced portions of said horizontal member and interconnected at their upper ends by means of a cross member extending therebetween, each of said upper sections including a pair of spaced and interconnected second upstanding tubular uprights telescoped over said first uprights, said scaffold board support means comprising portions of vertically spaced brace means extending between and secured to said tubular uprights.

12. The combination of claim 11 wherein sAid motor means includes an upright fluid cylinder having its upper and lower ends connected to said upper and lower sections, respectively, said fluid cylinder being of the double-acting type.