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Publication numberUS3504766 A
Publication typeGrant
Publication dateApr 7, 1970
Filing dateMar 13, 1968
Priority dateMar 13, 1968
Publication numberUS 3504766 A, US 3504766A, US-A-3504766, US3504766 A, US3504766A
InventorsBoyd Joseph Emmett
Original AssigneeBoyd Joseph Emmett
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Ladders
US 3504766 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

April 7, 1970 J. E. BOYD 3,504,766

Flag Fla? 56.10

INVENTOR JOSEPH EMMETT BOYD April 7, 1970 J. E. BOYD 3,504,766

LADDERS Filed March 13. 1968 2 Sheets-Sheet 2 Paalga INVENTOR JOSEPH EMMETT BOYD mmmm.

ATioRNEY United States Patent O 3,504,766 LADDERS Joseph Emmett Boyd, 4462 Fenwick, Warren, Mich. 48092 Filed Mar. 13, 1968, Ser. No. 712,787 Int. Cl. E06c 1/18 U.S. Cl. 182-104 12 Claims ABSTRACT OF THE DISCLOSURE Improvements in ladders are disclosed, comprising, in combination, at least a pair of ladder sections, each said ladder section having a pair of rails and rungs joining said rails, and hinge means hinging said ladder sections together side by side, the adjacent rails of said ladder sections connected together by said hinge means, said ladder sections swingable relative to each other via said hinge means between a stowage position in which said ladder sections are folded together for stowage and a work position in which said ladder sections are swung away from each other for use as a ladder.

Reference is made to my subsequent copending United States patent application Ser. No. 739,119 led June 2l, 1968, in which improvement in ladders not claimed herein are disclosed and claimed.

The principal object of my invention is the provision of improvements in ladders which extend their usefulness and permit results to be accomplished not heretofore attainable with ordinary ladders.

The foregoing object of my invention and its advantages will become apparent during the course of the following description, taken in conjunction with the accompanying drawings, in which:

FIGS. 1-11 are various views of a ladder embodying my invention; FIGS. 1 and 3 being bottom plan views of said ladder in different positions; FIGS. 2 and 4 being fragmentary front elevational views of the inverted structure of FIGS. 1 and 3, respectively; FIG. 5 being a side elevational view of said ladder; FIGS. 6-11 being fragmentary views of certain structure of the preceding FIGS.; and FIGS. 12-18 are various views of another ladder embodying my invention; FIG. 12 being a bottom plan view of said ladder in one position thereof; FIGS. 14, 15 and 16 being, respectively, side, top plan and perspective views of said ladder in another position thereof; FIG. 13 being a rear elevational view of said ladder in still another position thereof; and FIGS. 17 and 18 being fragmentary views of certain structure of the preceding FIGS.

Referring to the drawings in greater detail and rst to FIGS. l-ll, 20 generally designates the ladder shown therein embodying my invention. Said ladder 20 comprises ladder sections 30, 40 and 50 each of which has a pair of rails designated 31 and 32; 41 and 42; and 51 and 52, respectively, joined by rungs 33, 43 and S3. Hinge means 60 and 70 hinge together side by side the ladder sections 30, 40 and 40, 50, respectively, to form a wall supported ladder. The ladder sections 30, 40 and 50 are swingable relative to each other between a stowage position for stowage and a work position for use as a ladder. In said work position the three ladder sections are in 180 degree alignment with each other as shown in FIGS. 3-5. In said stowage position the two outboard ladder sections 30 and 50 fold against the intermediate ladder section 40 on opposite sides thereof as shown in FIGS. l and 2. In further combination with the foregoing structure length adjusting means is provided at the foot end of at least two rails for changing the effective length of the respective rail so that the ladder 20 can be maintained level on nonlevel supporting surfaces. In the instance length adjusting means is provided at the foot end of each rail and comprises a threaded rod threadably supported by well known means (not shown) at said foot end of each rail and carrying on its free end via a universal type joint an anchor plate having antiskid means on its engaging face. The head end of at least the two extreme outboard rails is provided with pivotally supported anti-skid means of the vertical surface engaging type which comprises a member 93 having anti-skid means on its engaging face pivotally connected to a member 92 anchored on said head end of the respective rail. In use of the ladder 20 the members 92 and 93 are made fast relative to each other at any preselected obtuse angle by well known means (not shown). The ladder sections 30, 40 and 50 mutually contribute to stability of the ladder 20 by being hinged together and make for a safer arrangement for workmen who need to work closely together at a height above the ground. Such workmen in groups of two or more can carry bulky and weighty objects up the ladder 20` and handle them together at heights above the ground while standing on the ladder 20. The hinge pins of the hinge means 60 and 70 may be removed to facilitate transport of the ladder sections 30, 40 and 50.

Referring now to FIGS. 12?-18, 200` generally designates the ladder shown therein embodying my invention. Said ladder 200 comprises ladder sections 300, 400 and 500 each of which has a pair of rails 310` and 320; 410y and 420; and 510 and S20, respectively, joined by rungs 330, 430 and 530. Hinge means 600 and 700 hinge together side by side the ladder sections 300, 400* and 300, 500, respectively, to form a self-supporting free standing ladder. The ladder sections '300, 400 and 500* are swingable relative to each other between a stowage position for stowage and a work position for use as a ladder. In said work position the two outboard ladder sections 400 and 500 are disposed on the same side of and at right angles to the intermediate ladder section 300- as shown in FIGS. 14-16. In said stowage position the two outboard ladder sections 400 and 500 fold against the intermediate ladder section 300 on the Same side thereof as shown in FIGS. 12. and 13. The intermediate ladder section 300 is multiple stance in width which means that a user can move his feet without impediment across the rungs 330 between the rails 310 and 320 for a distance several times greater than the width of the normal human stance. Means are provided for locking the outboard ladder sections 400 and 500 together in said 'work position which, in the instance, comprise, in one form, a plank 900 extending between the outboard ladder sections 400 and 500 in said work position. The plank 900 has spaced apart bars 910 fastened to the underside thereof bet-Ween which fit corresponding pairs of rungs 430 and 530gof the outboard ladder sections 400 and 500, respectively, to lock the outboard ladder sections 400 and 500 together in said work position. In another form said locking means comprises a railing 950 the free ends of which are insertable into apertures in anchor blocks fastened in the upper ends of the rails 410 and 510. In further combination with the foregoing structure length adjusting means is provided at the foot end of at least two rails for changing the effective length of the respective rail so that the ladder 200 can be maintained level on non-level supporting surfaces. In the instance length adjusting means 800y of the same construction as the length adjusting means 80 is provided at the foot end of the rails 310, 320, 410` and 510. More than one person at a time can use the ladder 200 to advantage. The ladder 200 can conveniently accommodate as many as four persons at a time, for example, one person on the rungs of each of the ladder sections 300, 400 and 500 and one person on the plank 9001. More work at a height above the ground in a less tiring manner, in less time and with less shifting of ladder positions can be accomplished with the ladder 200 than with a conventional step ladder. The ladder sections 300, 400 and 500are light enough to be transported as a unit in said stowage position.

It will thus be seen that there has been provided by my invention improvements in ladder in which the advantages hereinabove set forth together with many other thoroughly practical advantages has been successfully achieved. While a preferred embodiment of the invention has been shown and described it is to be understood that variations and changes may be resorted to without departing from the spirit of the invention as defined by the appended claims.

I claim:

1. In a ladder, the improvement comprising, in cornbination, three ladder sections forming a wall supported ladder, each said ladder section having a pair of rails and rungs joining said rails, and hinge means hinging the three ladder sections together side by side, the intermediate ladder section having its rails hinged to the respective adjacent rail of the outboard ladder sections, the three ladder sections swingable relative to each other via said hinge means between a stowage position in which said ladder sections are folded together for stowage and a work position in which said ladder sections are swung away from each other for use as a ladder, the three ladder sections in 180 degrees alignment with each other in said work position, the two outboard ladder sections folding against the intermediate ladder section on opposite sides thereof in said stowage position.

2. In a ladder, the improvement comprising, in combination, three ladder sections forming a self-supporting free standing ladder, each said ladder section having a pair of rails and rungs joining said rails, and hinge means hinging the three ladder sections together side by side, the intermediate ladder section having its rails hinged to the respective adjacent rail of the outboard ladder sections, the three ladder sections swingable relative to each other via said hinge means between a stowage position in which said ladder sections are folded together for stowage and a work position in which said ladder sections are swung away from each other for use as a ladder, the two outboard ladder sections disposed on the same side of and at right angles to the intermediate ladder section in said work position, the two outboard ladder sections folding against the intermediate ladder section on the same side thereof in said stowage position.

3. The improvement of claim 2, comprising, in further combination, means to lock the ladder sections together in said work position.

4. The improvement of claim 3 in which said lock means comprises a rail extending between the outboard ladder sections.

5. The improvement of claim 4 comprising, in further 55 combination, means in the outboard ladder sections to slidably receive and hold the ends of said rail.

=6. The improvement of claim 2 comprising, in further combination, a walk-upon Weight supporting means extending between the outboard ladder sections in said work position, and means on said walk-upon weight supporting means cooperating with the rungs of said outboard ladder sections locking the outboard ladder sections together in said work position.

7. The improvement of claim 6 comprising, in further combination, a rail extending between the outboard ladder sections locking said ladder sections together in said work position, said rail disposed so as to extend above and along the length of said walk-upon Weight supporting means.

8. The improvement of claim 2 in which said intermediate ladder section is disposed at an obtuse angle to the horizontal.

9. The improvement of claim 8 in which a rail of each said outboard ladder section is disposed at an obtuse angle to the horizontal.

10. The improvement of claim 2 in which the intermediate ladder section is multiple stance in width.

11. The improvement of claim 2 comprising, in further combination, means to lock the outboard iadder sections together in said work position.

12. In a ladder, the improvement comprising, in combination, a pair of outboard ladder sections, a third section intermediate between said pair of outboard ladder sections, the three sections forming a self-supporting free standing ladder, each said outboard ladder section having a pair of rails and rungs joining said rails, said intermediate section having a pair of rails, and hinge means hnging the three sections together side by side, said intermediate section having its rails hinged to the respective adjacent rail of the outboard ladder sections, the three sections swingable relative to each other via said hinge means between a stowage position in which said sections are folded together for stowage and a work position in which said sections are swung away from each other for use as a ladder, the two outboard ladder sections disposed on the same side of and at right angles to said intermediate section in said work position, the two outboard ladder sections folding against said intermediate section on the same side thereof in said stowage position.

References Cited UNITED STATES PATENTS 510,427 12/1893 Hine 1GO-135 882,161 3/1908 Olive 182-104 1,280,291 10/1918 Phelps 160-135 2,573,156 10/1951 Meyers 160-135 2,855,037 10/1958 Stilel 160--135 2,994,402 8/ 1961 Tyler 182-152 2,718,346 9/1955 Galen 182-104 2,987,148 6/1961 Millard 182-152 2,593,386 4/1952 Dirks 182-152 REINALDO P. MACHADO, Primary Examiner U.S. Cl. X.R. l82-152, 119

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US510427 *Aug 8, 1892Dec 12, 1893 Voting booth
US882161 *Jul 1, 1907Mar 17, 1908Leonidas T OlivePortable ladder-like scaffold.
US1280291 *Nov 5, 1917Oct 1, 1918Byron PhelpsDeflector for air-currents.
US2573156 *Apr 22, 1946Oct 30, 1951G H Specialty CompanyScreen with removable panel
US2593386 *May 21, 1948Apr 15, 1952Daisy DirksFolding scaffold
US2718346 *Jan 26, 1953Sep 20, 1955Max GalenLadders
US2855037 *Jan 30, 1956Oct 7, 1958Theophile A StiffelPortable wall or panel structures and means for supporting same
US2987148 *Aug 26, 1955Jun 6, 1961Reeson Millard JohnExpansible structural member
US2994402 *Jul 21, 1958Aug 1, 1961Tyler Kenneth EScaffold unit construction
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4478549 *May 20, 1983Oct 23, 1984Curtis StellyFoldable loading ramp for all terrain/recreational vehicles and the like
US4638604 *May 7, 1984Jan 27, 1987Stage Rite CorporationStaging structure
US8056678 *Dec 6, 2004Nov 15, 2011Sullivan Sidney JModular ladder assembly
US20130048426 *Aug 17, 2012Feb 28, 2013Dale EkdahlGrain Rescue Apparatus and Method of Rescue
Classifications
U.S. Classification182/104, 182/119, 182/152
International ClassificationE06C7/44, E06C7/00
Cooperative ClassificationE06C7/44
European ClassificationE06C7/44