US3212605A - Portable scaffold - Google Patents

Portable scaffold Download PDF

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US3212605A
US3212605A US392095A US39209564A US3212605A US 3212605 A US3212605 A US 3212605A US 392095 A US392095 A US 392095A US 39209564 A US39209564 A US 39209564A US 3212605 A US3212605 A US 3212605A
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scaffold
upper
lower
end
posts
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US392095A
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Robert L Dickerson
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Robert L Dickerson
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    • EFIXED CONSTRUCTIONS
    • E04BUILDING
    • E04GSCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR OTHER BUILDING AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
    • E04G1/00Scaffolds primarily resting on the ground
    • E04G1/34Scaffold constructions able to be folded in prismatic or flat parts or able to be turned down

Description

Oct. 19, 1965 Filed Aug. 26, 1964 2 Sheets-Sheet 1 FI.G l I E v -i m MI ROBERT L. DICKERSON INVENTOR.

ATTORNEYS Oct. 19, 1965 R. L. DICKERSON PORTABLE S CAFFOLD 2 Sheets-Sheet 2 Filed Aug. 26, 1964 FIG FIG

ROBERT L. DIOKERSON INVENTOR.

ATTORNEYS United States Patent 3,212,605 PORTABLE SCAFFOLD Robert L. Dickerson, 3536 Stoneway, Seattle, Wash. Filed Aug. 26, 1964, Ser. No. 392,095 7 Claims. (CL 182119) This invention relates to movable scaffolds and more particularly to a type of collapsible scaffold having vertically adjustable work platforms. This is a continuationin-part of pending application Serial Number 257,613, filed February 11, 1963, which is in turn a continuationin-part of abandoned application Serial Number 128,463, filed August 1, 1961.

It is a principal object of my invention to provide a new and improved scaffold which embodies novel details of construction in its frame work and in the means for removably securing the working platform to the frame when in use and when collapsed for storage.

Further objects of my invention are to provide a scaffold of this type which is sturdy, which is convenient both to use and to store, which can easily be assembled in its expanded working position or collapsed to its storage position, and which is stable in both such positions.

These and other objects will appear in the course of the following description and claims, the invention consisting in the novel construction and in the adaptation and combination of parts hereinafter described and claimed.

In the accompanying drawings:

FIG. 1 is a side elevational view of a scaffold embodying the preferred teachings of my invention.

FIG. 2 is a detail horizontal sectional view taken on line 22 of FIG. 1.

FIG. 3 is a side elevational view showing the scaffold in collapsed position.

, FIG. 4 is an end view of the scaffold while in collapsed condition.

FIG. 5 is a fragmentary vertical sectional view to an enlarged scale taken on line 55 of FIG. 3; and

FIG. 6 is a detail vertical sectional view taken as indicated by line 6-6 in FIG. 4 and with one of the platforms in working position on the upper rungs of the ladder sections.

Referring to the accompanying drawings it is seen that V the scaffold of the present invention comprises end ladder sections 12 which are joined between the lower portions thereof by side parallel linkages 13. The ladder sections provide means to support working platforms 14 which may be positioned at selected levels.

Each ladder section 12 includes a pair of corner posts 16 which are of channel form comprising a web 17 and spaced flanges 18-18. Vertically spaced rungs 20 extend horizontally between each pair of corner posts and are welded to the flange 18'. The rungs also are of channel form and each includes an upstanding outer flange 21 and an upstanding inner flange 23 'of reduced height connected by a horizontal web 22 providing a support for the ends of the platforms 14.

The platforms 14 may be solid wood planks or grates and to retain them on the rungs 20 I provide locating bars 24 which are riveted to the bottom side of the platforms at both ends thereof. When one of the platforms is placed between a pair of horizontally aligned rungs, its bars 24 fit into the channel grooves defined by the flanges 21 and 23 of the rungs. In this manner the platforms aid 3,212,605 Patented Oct. 19, 1965 ice the side linkages 13 in holding the end ladder sections 12 upright. The width of each working platform 14 is approximately one-half the length of the rungs 20 so that a pair of platforms may be placed side by side or at different levels. In the latter instance, the platforms may be placed directly above one another or, as will more commonly be the case, they maybe offset with respect to one another so as to be in a stepped arrangement.

Each corner post 16 rests on a related caster unit 25 anchored thereto by bolts 26. The caster wheels are swivel-mounted to permit the scaffold to be moved along the ground surface in any direction and each is provided with an individual braking device which provides for convenient locking and release of the casters by means of related pedals 27-28. The braking device may be of the type described in United States Patent No. 1,471,307.

The parallel linkages 13 at the longitudinal sides of the scaffold each have three-part upper and lower toggle mechanisms, the upper toggle comprising a right arm 30, elbow link 31, and left arm 32, while the corresponding parts of the lower toggle are designated 33, 34 and 35. Each of the upper toggle arms is formed as a downturned channel of a width to fit at its outer end between the flanges 18-18 of the related corner post 16 and be pivotally connected therewith by bolts 36. The upper elbow links 31 may be formed of the same channel stock as the posts 16 so as to fit over the inner ends of the upper toggle arms and be pivotally connected thereto by bolts 37 in similar manner to the connection 36 between the outer ends of arms and the corner posts.

It will be noted that the inner ends of each set of the upper toggle arms are spaced apart to receive the upper end portion of a vertical connecting rod 38 the-rebetween. These rods 38 are secured to the flanges 31a of the upper elbow links 31 by a cross-bar 40 which passes by necked threaded ends 40a through the flanges 31a, the rods 38 and related washers 41, and receives nuts 42. In addition to functioning as a pair of bolts, the cross-bar 40 also serves as both a center cross-brace and as a lift handle by which the toggle mechanisms can be upwardly broken to collapse the scaffold.

Instead of being of channel stock, the lower elbow links 34 and lower toggle arms 33, 35 are formed from flat bar stock. At their outer ends the lower toggle arms rests against the outer back face of the inner posts 16, and at their inner ends they occupy a position behind the related elbow links 34. Bolts 43 and 44 pivotally connect the lower toggle arms to the corner posts and the links 34, respectively.

At their lower end the inner faces of the rods 38 are cut back as shown in FIG. 5 to present flat surfaces 38a opposing the outer faces of the links 34 and shoulders 38b bearing against the upper edge of the links. Bolts 45 connect the rods 38 and links together. In this regard, although not detectable in the drawings, the vertical distance at each side of the scaffold between the pivots 37 and 44 on the links 31 and 34 is made slightly greater than the vertical spacing on each post 16 between the pivots 36 and 43 so that when the scaffold is in its expanded position (FIG. 1), the pivots 44 are past center, i.e. the pivots 44 are slightly below the level of the pivots 43 whereas the upper pivots 36 and 37 are in coplanar horizontal alinement. This arrangement serves as a lock to resist any tendency for the scaffold to fold up while being moved about in its expanded operational condition.

The side parallel linkages 13 each include a pair of diagonal knee braces 46-46 which are pivotally connected at their lower ends to the corner posts 16 by the bolts 43. From the lower end of the related posts 16 the knee braces of each pair converges upwardly to bolts 37 serving as pivots between the braces and a respective slide block 48. These blocks 48 are sleeved on the rods 38 and bear against the lower edge of the flanges 31a of the upper elbow links 31 when the scaffold is expanded. During collapsing of the scaffold the blocks 48 ride down the rods 38 toward the lower el bow links 34 as shown in FIG. 3.

Each ladder section 12 is provided with a vertically adjustable hand rail unit 50 which is of channel crosssection and inverted U-configuration providing vertical legs 51 depending from the ends of the rail proper, denoted 52. The rail legs 51 are slidably received by the corner posts 16 and each has its channel flanges 51a directed toward the outer flange 18 of the respective corner post to receive a nut 53 therebetween. Each of these nuts 53 is threaded onto a locking screw 54 which passes outwardly through the outer flange 18 of the related post to a handle head 54a. When the locking screws 54 are tightened they bear against the web 51b of the rail legs and force them against the inner flanges 18 of the corner posts thereby locking the hand rail units 50 against vertical movement. Raising or lowering of the hand rails 50 to the desired height is readily accomplished by manually turning the exposed handles 54a to release the screw locks on the rail legs 51, slide adjusting the elevation of the hand rails, and then resetting the locking screw 54.

As can be seen in FIG. 3, a pair of hanger cleats 55 is screw-connected to the underside of each of the platforms 14 and is arranged to hook over the outer flange 21 of one of the rungs 20 when the platform is placed on end. In this manner the platforms 14 may be conveniently stored with the rest of the scaffold.

To erect the scaffold into its work position, the platforms 14 are lifted to free their hanger cleats 55, the ladder sections are pulled apart to fully expand the side linkages 13 and lower the pivots 44 past center. Then the platforms 14 are placed at the desired height or heights on the respective rungs 20 with the locating bars 24 of each platform seated on the web 22 and fitting between the flanges 21 and 23 of the rungs. With the locating bars so engaged the platforms are retained in fixed position and contribute to the stability of the platform. The hand rails 52 may be moved to the desired height and locked in position as afore described. In use, the workman can easily roll the scaffold on its casters 26 from place to place on the work site and set the caster brakes for safety.

T o prepare the scaffold for compact storage, the hand rails 52 are lowered by releasing the locking screws 54, the platforms 14 are lifted from the ladder sections 12, the cross bar 40 is lifted to collapse the scaffold, and the platforms are hung by their cleats 55 on one of the rungs 20.

It is thought that the invention will have been clearly understood from the foregoing detailed description. Changes in the details of construction will suggest themselves and may be resorted to without departing from the spirit of the invention, wherefore it is my intention that no limitations be implied and that the hereto annexed claims be given a scope fully commensurate with the broadest interpretation to which the employed language admits.

What I claim as new is:

1. A collapsible scaffold comprising, an exposed pair of vertical end support sections each including a pair of laterally spaced posts, parallel side linkages connected between the posts of said end sections for vertical jackknifing action whereby the end sections may be expanded to a fully spaced working position or brought close together to a collapsed storage :position, each of said parallel side linkages having upper and lower parallel toggle mechanisms, each said upper toggle mechanism including a center upper elbow section and a pair of upper toggle arms pivotally connected to the upper elbow section and to the end posts at the respective side of the scaffold, and each said lower toggle mechanism including a center lower elbow section and a pair of lower toggle arms pivotally connected to the lower elbow section and to the end posts at the respective side of the scaffold, a respective vertical connecting bar in each of said parallel side linkages extending between the upper and lower elbow sections thereof, a respective slide block sleeved on each of said connecting bars, and a respective pair of diagonal knee braces in each of said parallel side linkages pivotally connected to the respective said slide block and to the end posts at the respective side of the scaffold.

2. The scaffold of claim 1 in which said vertical connecting bars are interconnected by a transverse bracing bar whereby collapsing of said scaffold may be accomplished by pulling said bracing bar upwardly.

3. The scaffold of claim 1 in which the lower elbow links are sprung downwardly past center when the scaffold is in its expanded working position.

4. The scaffold of claim 1 in which each of said end posts has a respective caster unit at its lower end comprising a caster wheel and a lock mechanism for selectively locking the wheel.

5. The scaffold of claim 1 in which one of said end sections carries a transverse hand rail with legs at its end depending into the posts of the respective end section, each of said legs having a channel cross-section, and a respective locking device for each of said legs comprising a nut nesting in the leg, and a screw passing from its head through the respective post, threaded through the nut, and bearing against the leg.

6. The scaffold of claim 1 in which each of said end support sections has its posts connected by a plurality of vertically spaced rungs spaced above said side linkages, and in which removable platform means is provided for placing at selected levels between said end support sections on said rungs, the end portions of said platform means and the rungs of said end support sections detachably interlocking with one another when said platform means is placed in working position between said end support sections in a manner holding said end support sections against movement endwise of and relative to said platform means, the interlock between said platform means and said rungs being released by vertical movement of said platform means relative to said rungs.

7. A collapsible scaffold comprising, removable platform means, two vertical end ladder sections each comprising two posts connected by a plurality of vertically spaced rungs, parallel side linkages operatively connected between said ladder sections near the lower end thereof and below the level of a majority of said rungs so that said ladder sections may be brought close together to a collapsed storage position or be expanded to a fully spaced working position wherein said platform means may be placed at selected levels between said ladder sections to be supported by the rungs thereof, the end portions of said platform means and the rungs of said ladder sections detachably interlocking with one another when said platform means is placed in working position between said ladder sections in a manner holding said ladder sections against movement endwise of and relative to said plat form means, the interlock between said platform means and said rungs being released by vertical movement of said platform means relative to said rungs, said parallel linkages at each side of said scaffold comprising respective upper and lower parallel toggle mechanisms which jackknife upwardly at vertically spaced elbows midway between said ladder sections and a respective vertical con necting bar extending between said connecting bars whereby collapsing of the scaffold may be effected by pulling said bracing bar upwardly after removing said platform means, a pair of slide blocks sleeved on said vertical connecting bars and bearing against the underside of the elbow of the upper toggle mechanisms when the scaffold is in expanded working position, and a pair of diagonal knee braces for each side of the scaffold pivotally connected at their upper ends to the respective slide block and at their lower ends to the lower ends of the posts on the corresponding side of the scaffold.

References Cited by the Examiner UNITED STATES PATENTS Chenoweth 182152 X Waltz 182152 Dirks 182--152 Thomas 182-452 Mitchell 182-222 X HARRISON R. MOSELEY, Primary Examiner.

Claims (1)

1. A COLLAPSIBLE SCAFFOLD COMPRISING, AN EXPOSED PAIR OF VERTICAL END SUPPORT SECTIONS EACH INCLUDING A PAIR OF LATERALLY SPACED POSTS, PARALLEL SIDE LINKAGES CONNECTED BETWEEN THE POSTS OF SID END SECTION FOR VERTICAL JACKKNIFING ACTION WHEREBY THE END SECTIONS MAY BE EXPANDED TO A FULLY SPACED WORKING POSITION OR BROUGHT CLOSE TOGETHER TO A COLLAPSE STORAGE POSITION, EACH OF SAID PARALLEL SIDE LINKAGES HAVING UPPER AND LOWER PARALLEL TOGGLE MECHANISMS, EACH SID UPPER TOGGLE MECHANISM INCLUDING A CENTER UPPER ELBOW SECTION AND A PAIR OF UPPER TOGGLE ARMS PIVOTALLY CONNECTED TO THE UPPER ELBOW SECTION AND TO THE END POSTS AT THE RESPECTIVE SIDE OF THE SCAFFOLD, AND EACH SAID LOWER TOGGLE MECHANISM INCLUDING A CENTER LOWER ELBOW SECTION AND A PAIR OF LOWER TOGGLE ARMS PIVOTALLY CONNECTED TO THE LOWER ELBOW SECTION AND TO THE END POSTS AT THE RESPECTIVE SIDE OF THE SCAFFOLD, A RESPECTIVE VERTICAL CONNECTING BAR IN EACH OF SAID PARALLEL SIDE LINKAGES EXTENDING BETWEEN THE UPPER AND LOWER ELBOW SECTIONS THEREOF, A RESPECTIVE SLIDE BLOCK SLEEVED ON EACH OF
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Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3312305A (en) * 1965-08-02 1967-04-04 Leo S Waun Folding scaffold
US3675736A (en) * 1971-05-03 1972-07-11 Baker Roos Inc Guard rail assembly for a platform
FR2227752A5 (en) * 1973-04-27 1974-11-22 Duarib Ets
US3997024A (en) * 1975-11-19 1976-12-14 Fredricks Anthony T Portable scaffold ladder
US4088202A (en) * 1976-08-25 1978-05-09 Costello Clifford T Scaffolding cart
US4102555A (en) * 1977-01-31 1978-07-25 Thaddeus Tobolski Folding work table apparatus
US4534447A (en) * 1984-04-03 1985-08-13 Lucien Champigny Foldable ladder scaffold
US4917217A (en) * 1989-01-23 1990-04-17 Stageright Corporation Portable folding staging
US5121812A (en) * 1989-09-28 1992-06-16 Takenaka Corporation Folding scaffold unit
EP0754819A1 (en) * 1995-07-20 1997-01-22 Tatsuo Ono Shore
US6105719A (en) * 1998-11-05 2000-08-22 Rel Products Inc. User-configurable mechanics stool
US6450291B1 (en) * 1997-12-26 2002-09-17 Nisso Sangyo, Co., Ltd. Frames and structures assembled by same
US20050167195A1 (en) * 2004-01-30 2005-08-04 Gary Chipman Safety rail for scaffolding
GB2443487A (en) * 2006-11-03 2008-05-07 Birchwood Products Ltd Collapsible work stand
FR2934290A1 (en) * 2008-07-23 2010-01-29 Tubesca Folding scaffolding element for use as lower element of multistage scaffolding, has upper and lower bars folded in vertical plane along reduced volume where ladder elements are moved closer to one another, in unserviceable position
US20100326938A1 (en) * 2009-06-25 2010-12-30 Shou Qiang Zhu Foldable and portable storage shelf
GB2486015A (en) * 2010-12-02 2012-06-06 Turner Access Ltd Folding platform safety unit
US20130043095A1 (en) * 2011-08-16 2013-02-21 Stephen H. Thacker Masonry scaffold system with truss level rosettes
ITCR20130008A1 (en) * 2013-03-01 2014-09-02 Franco Montani Scaffold foldable with built-in scale
US20150090532A1 (en) * 2012-04-19 2015-04-02 Sorlandsstigen As Collapsible escape ladder with guards
US9226574B1 (en) * 2014-09-23 2016-01-05 Protrend Co., Ltd. Foldable multi-shelf stand
CN105386223A (en) * 2015-12-28 2016-03-09 江苏国茂纺织科技有限公司 Metal plate machine frame
CN105568536A (en) * 2015-12-28 2016-05-11 江苏国茂纺织科技有限公司 Metal plate rack for flat knitting machine

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2285901A (en) * 1942-03-30 1942-06-09 Albert J Chenoweth Material handling scaffold
US2394221A (en) * 1945-04-13 1946-02-05 Homer B Waltz Platform scaffold
US2593386A (en) * 1948-05-21 1952-04-15 Dirks Daisy Folding scaffold
US2599670A (en) * 1950-02-01 1952-06-10 George G Thomas Foldable scaffold for household uses
US2767032A (en) * 1952-05-29 1956-10-16 Mitchell Maintenance Company I Platform for painting poles

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2285901A (en) * 1942-03-30 1942-06-09 Albert J Chenoweth Material handling scaffold
US2394221A (en) * 1945-04-13 1946-02-05 Homer B Waltz Platform scaffold
US2593386A (en) * 1948-05-21 1952-04-15 Dirks Daisy Folding scaffold
US2599670A (en) * 1950-02-01 1952-06-10 George G Thomas Foldable scaffold for household uses
US2767032A (en) * 1952-05-29 1956-10-16 Mitchell Maintenance Company I Platform for painting poles

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3312305A (en) * 1965-08-02 1967-04-04 Leo S Waun Folding scaffold
US3675736A (en) * 1971-05-03 1972-07-11 Baker Roos Inc Guard rail assembly for a platform
FR2227752A5 (en) * 1973-04-27 1974-11-22 Duarib Ets
US3997024A (en) * 1975-11-19 1976-12-14 Fredricks Anthony T Portable scaffold ladder
US4088202A (en) * 1976-08-25 1978-05-09 Costello Clifford T Scaffolding cart
US4102555A (en) * 1977-01-31 1978-07-25 Thaddeus Tobolski Folding work table apparatus
US4534447A (en) * 1984-04-03 1985-08-13 Lucien Champigny Foldable ladder scaffold
US4917217A (en) * 1989-01-23 1990-04-17 Stageright Corporation Portable folding staging
US5121812A (en) * 1989-09-28 1992-06-16 Takenaka Corporation Folding scaffold unit
EP0754819A1 (en) * 1995-07-20 1997-01-22 Tatsuo Ono Shore
US6450291B1 (en) * 1997-12-26 2002-09-17 Nisso Sangyo, Co., Ltd. Frames and structures assembled by same
US6105719A (en) * 1998-11-05 2000-08-22 Rel Products Inc. User-configurable mechanics stool
US20050167195A1 (en) * 2004-01-30 2005-08-04 Gary Chipman Safety rail for scaffolding
US6932194B1 (en) 2004-01-30 2005-08-23 Gary Chipman Safety rail for scaffolding
GB2443487A (en) * 2006-11-03 2008-05-07 Birchwood Products Ltd Collapsible work stand
FR2934290A1 (en) * 2008-07-23 2010-01-29 Tubesca Folding scaffolding element for use as lower element of multistage scaffolding, has upper and lower bars folded in vertical plane along reduced volume where ladder elements are moved closer to one another, in unserviceable position
US20100326938A1 (en) * 2009-06-25 2010-12-30 Shou Qiang Zhu Foldable and portable storage shelf
US20110068072A1 (en) * 2009-06-25 2011-03-24 Shou Qiang Zhu Foldable and portable storage shelf
US8256630B2 (en) * 2009-06-25 2012-09-04 Shou Qiang Zhu Foldable and portable storage shelf
US8256629B2 (en) * 2009-06-25 2012-09-04 Shou Qiang Zhu Foldable and portable storage shelf
GB2486015A (en) * 2010-12-02 2012-06-06 Turner Access Ltd Folding platform safety unit
US20130043095A1 (en) * 2011-08-16 2013-02-21 Stephen H. Thacker Masonry scaffold system with truss level rosettes
US20150090532A1 (en) * 2012-04-19 2015-04-02 Sorlandsstigen As Collapsible escape ladder with guards
ITCR20130008A1 (en) * 2013-03-01 2014-09-02 Franco Montani Scaffold foldable with built-in scale
WO2014132281A1 (en) * 2013-03-01 2014-09-04 Montani Franco Folding scaffold with built in ladder
US9226574B1 (en) * 2014-09-23 2016-01-05 Protrend Co., Ltd. Foldable multi-shelf stand
CN105386223A (en) * 2015-12-28 2016-03-09 江苏国茂纺织科技有限公司 Metal plate machine frame
CN105568536A (en) * 2015-12-28 2016-05-11 江苏国茂纺织科技有限公司 Metal plate rack for flat knitting machine

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