US1973774A

US1973774A - Stepladder

Info

Publication number: US1973774A
Application number: US668525A
Authority: US
Inventors: Pflugradt Alfred
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-04-29
Filing date: 1933-04-29
Publication date: 1934-09-18
Anticipated expiration: 1951-09-18

Description

Sept. l8`, 1934. A. PFLUGRABT y 1,973,774

STEPLADDER Filed April 29. 1955 2 swing-sheet4 1 INYENTQR I ATT'oRNEY v Sept. 18,1934. I A PFLUGRADT V V l,97 3,774

'STEPLADDER VFiled April 29, 1953 2 Sheets-Sheet'y 2 INVENToR ATToRNi-:Ys

Patented Sept. 18, 1934 1973374 z STEPLADDER Alfred Pflugradt, Milwaukee, Wis. Application April 29, 1933, serial; No. 668,525

6 Claims.

My invention relates to improvements in stepladder assemblies.l

The object of. my invention is to provide va stepladder which is capable of being separated `i` into relatively small units of such light weight as to be easily handled and adjustedfor ordinary purposes, to facilitate reaching .shelving, ceilings of rooms, or lower branches of' trees. -It is also my object to provide aV jointed stepladder of great strength and durability, although constructed of separable parts.

It is my object to construct stepladders in units adapted to be usedV independently or in assembled superposed relation, one of the units being adapted to serve as the top of asteplad-` derof any height determinable by superposing such unit upon one ormore associated units, each adapted to form the base of a stepladder or an intermediate section thereof.

Specific objects arev to provide means for adequately and safely connecting 'stepladder units with each other; to provide adequate bracing for the connected units; to provide means whereby the units .may be readily folded as a single package for storage and transportation purposes; and to provide safety locks for jointed stepladders, whereby they may be securely hel in an extended relation. 1

In the drawings: o

Figure 1 is a side elevation of a stepladder unit adapted to serve as the top unit for an extended ladder. z

Figure 2 is a side elevation of anassociate stepladder unit adapted to be used separately or in association with the unit shown in Figure 1, or with other units like that shown in-y Figure 2, and with which the unit shown in Figure 1 has been assembled as a top unit.

Figure 3 is an enlarged fragmentary view of one of the hinge joint -connections of two as.- sembled ladder sections. V A

Figure 4 is a view of the same showing said members and their connections in detached relation.

Figure 5 is an enlarged Sectional view drawn to line 5-`5 of Figure' 2). o f

Figure 6 is a side elevation, showing two of the stepladder units in assembled relation j to produce a stepladder of substantially double height as compared with that shown in Figure 1.

Figure 7 is a front elevation showing a modification. V I

Figure 8 is a side view, showing two of the 55 units folded and prepared for storage.

Like parts are identified by the same reference characters: throughout the several views.

The unit disclosed in Figure 1 is a short ladder having side bars 10 connected at intervals by cross bolts 11 and steps 12',the1atter being pref- 60. erably located directlyV above vthe bolts and supported by angle brackets` 13, through the vertical flange of ``Which the bolts preferably extend, as best illustrated in Figure 2. The horizontal flange of each bracket .may serve as a spacer 65.- interposed between the end of the. step and the bolt, whereby the bolt is made to cooperate with the bracket in supporting the step from the associated side bar independently of screwsor other connections, such as are 'ordinarily used to connect step supporting brackets with the side bars.

The top step or cap piece 15 is supported from the side bars 10 Vby special brackets 16, each connected with one of the side: bars 10 by a bolt 17 which also' serves to connect the' associated brace bar 18 with the'bar` 10. The upper end of thebrace bar 18.preferably has 'a metal sheath y In conformity with .ordinary practice,` -the brace bars 18 are Vreenforced by diagonal cross 30.. braces 22 and are detachably connected with the side bars 101 by stays A23 having hook-shaped extremities adapted to removably engage fprojections 24 on the bars 10, whereby these stays may be disconnected and folded upon the brace bars 18; The shelf 25 is also of Ordinary construction and pivotally supported from the brace bars V'10 by the shelf supporting arms'26.

. It will be observed thatV the brace bars of each setare morewidely spaced from each other than 9 the step supporting side' Abars and V so hinged thereto as to permit the.brace bars to fold at the sides of the step .supporting bars. For example, the brace bars 18 are so connected withV the side bars `10 underneath the'cap-'step 15 as to permit the brace Vbars to swing to a folded position at the sides and parallel with the bars 10, whereby the `hinged extension bars 10a,`hereinafter described, may be folded upon the edges of the bars 10 as shown in Fig. 8, and embraced by the 10 extension bars `18h `toform a compact 'package for transportation or storage. i f

. The lower'ends'of Vthe side bars-10 lare provided With hinge members 31 having-bearing faces 32.to receive azcounterpart'hinge member,

`socketed. lThe hinge member 31 is apertured atV 34 -to receive a hinge'pin 35, and at 36 to 'receive 10 a sheath-like extension 43 in which the upper' end of the associated ladder bar 10a is socketed.

The looking pin 37 is preferably connected With the step 12a by a suitable chain 45; v z

The side bars 18a. of thebrace are connected With a hinge member 41 b'y "bolfts 1528 Whhthev unit is separately used as a small ladder. ,#The cross braces 22a and stays 23a are similar to the corresponding parts 22 -and23 lin 'Figure-1.

Assuming that the two ``ladderv units illustrated in Figurel and Figure 2. are to be assembled 'as shown in Figure 6, the -brace bars 1'8 Will first be disconnected by removingthe bolts 48 and'disengagingthe. sta'ys 23a. 'Ther'eupon the side bar 10a of this unit may have theshinge members 41 at their upper ends connectedby the hinge pins or bolts 35 .(*Figures 'Szand 4) with 'the hinge members 31 of `.the `ladder unit illustrated in Figure 1. The. hinge boltsjor pintles 35 preferably have threaded inner ends to receive a special nut 50 provided Withia pivoted handle 51 and an annular flange `52, whereby. this nut. may

J be manually. adjusted'upon the pint1e-35 to hold the bearing surfaces 32d Vand 42 in frictional con'- tact with each other. It will. be observed .that the hinge member,41 hasa shoulder' at 53 upon which thelower margin'54. of .the hinge member 31 may. bear when the sidebars loand. .10a of the two ladder. units arealigned.V

, When inztheyposition .of alignment the'lockin'g pin 37 Will be inserted in the holes 36a and 36 of the hinge members 41 and31, thereby looking the hinge with the ladder vsections 10a and 10 in alienment.... z When the bolts 48 are removed to' disconnect the .brace bars 18a from the hinge members '41 preparatory to assembly as a part'ofan-extension laddenzthesegbolts .48 and their associated washers 56 are preferably inserted thrugh-aper tures` 57 in,l thev sheath--43, wher'eupon .they icooperate with the upper orossrod 11 for securely holding the sheath to its ,associated side bar 10a. The brace'bars 18d are then aligned with-the brace bars 18,of the Figure 1l unit, and: the sheath 38 ,'is moved downwardlyto .embrace the upper ends,A of the brace bars '18aand secured to both bars by the looking detents `39 of ordinary'type. o The stays 23a may remain folded againstfthe side bars 18a When the parts are assembled to form the, extension ladder shown in/Figure'l 6. If desired, the `lower ends of the bars 18a1may be provided with sheaths 38a, similar to 'the 'v sheaths 38, and similarly; connected and adaptedfor adjustment to connect another extension unit in the same manner that the'sheaths 3'8 are employed to connect the, Figure-2- unit with I thefFigure 1 unit;

mally be folded along the brace bars 18a When not in use, but when the units are assembled to form an extension ladder the hook-shaped upper ends 63 of these stay rods may be engaged with projections 64 on the hinge members 31a. Also, these stay rods may be provided with pivoted extension members 66, Which also have hook-shaped ends 67.

The step supporting side bars 10h` and brace bars 181) of the lower unit may be outwa'rdly or ,divergently curved in the direction of their lower Therefore, the side bars of this unit will not requirehinge members at their lower ends.

Referringto Figure 8, it will be observed that When the units are connected in superposed relation as shown in Figure 7, the lower set of bracying bars may be disconnected and the lower set of step. supporting-'bars maybe swung..upon the intermediate hinge to folded position after first withdrawing. the :keyz 37. Thereuponthe idetached brace barsv` may -be placedupon the folded sections landsecured thereto 'by links 68 .similar to the stay -23, and normally disposed in Vparallel relation lto the -bracebars VIzclaim:

1.. Aset of stepladdersprovided with mutually. engageable. couplingzmembers adapted lto connect the stepladder elements in superposed relation to form va single stepladder of increased height, o'ne .of said stepladders havinga oapping top step, and the other stepladder havingzits steps spacedxequally' from eachother and from the lower stepv'of Vthe. other ladder. .whense'cured in 'extended relation thereto. f .f z

-2. A stepladder fprovided yWithl hinge members having a capping -top step 'and lsecured to =the upper .ends of itssidebars, and alsoihaving hinge memberssecured to. :the llower ends of its side bars, ein combination :with-an associated stepl'ad'- der. having hinge members at the upper ends of its -side bars engageable in hinged relation to Vthe hinge members .at the l-lower .ends 'of the 'fside bars of the first mentioned ladder,-eachzof said ladders .being 'provided4 with bracing; vmembers adapted to be coupled end to. end Vwhenithe step supporting portions are superposed, the fbracing membersof one ladder being provided with sliding couplings, :each adapted in-onej-positionfor connecting bracing members of both laddersof the set when thepairs ,of bracing membersare ingend to end adjustment... H 1 :3. The combination with aset of stepladders having'step supporting'fsidebars :anda pair of bra0ing ,,membe1's normally tpivotally connected with the upper ends of the respective. side bars, means forconnecting the side barskend tozend, and means for 'manuallyfl releasingone pair of bracing bars from their associated side vbars and connecting them endto end with'the braeing bars, of= the other stepladder, 'the bracing 'bars of 'one ladder being 'provided' with' 'sli'e'aths adapted to Vslide thereon to a joint covering position of engagement with the bracin'g bars of both ladders of the set when the pairs of :bracing bars-'are in end to-end'adjustment.

54.' -A stepladder vunit `vhaving lfstep supporting side'I bars provided 'with one-way 'hinge in'e'mbers fat'their 'lowerieiidsadapted to 'be' coupled toextension'side bar me`mbers, in combination with bracing bars pivotally connected withithe upper-ends of :'saidi'sideY barsfand. provided with res Vsheaths at theirlowerzends':adapted to-beiinoved step bars to fold upon the inner margins of those of the other set.

6. A set of folding step ladders, each having hinged bracing Vmembers, one of said ladders having a capping top step, and the other having its top step below the hinge connection of its bracing member, and means for separately securing the last mentioned step and bracing members to the lower ends of the respective step and bracing members of the ladder having the capping top step.

ALFRED PFLUGRADT.