US3005513A - Stepladders and structural components thereof - Google Patents

Stepladders and structural components thereof Download PDF

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Publication number
US3005513A
US3005513A US801751A US80175159A US3005513A US 3005513 A US3005513 A US 3005513A US 801751 A US801751 A US 801751A US 80175159 A US80175159 A US 80175159A US 3005513 A US3005513 A US 3005513A
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Prior art keywords
rails
rail
stepladders
web
attached
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Expired - Lifetime
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US801751A
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Clayton E Larson
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WHITE METAL ROLLING AND STAMPING CORP
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WHITE METAL ROLLING AND STAMPING CORP
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Priority to US801751A priority Critical patent/US3005513A/en
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    • EFIXED CONSTRUCTIONS
    • E06DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06CLADDERS
    • E06C1/00Ladders in general
    • E06C1/02Ladders in general with rigid longitudinal member or members
    • E06C1/14Ladders capable of standing by themselves
    • E06C1/16Ladders capable of standing by themselves with hinged struts which rest on the ground
    • E06C1/20Ladders capable of standing by themselves with hinged struts which rest on the ground with supporting struts formed as poles
    • EFIXED CONSTRUCTIONS
    • E06DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06CLADDERS
    • E06C7/00Component parts, supporting parts, or accessories
    • E06C7/08Special construction of longitudinal members, or rungs or other treads
    • EFIXED CONSTRUCTIONS
    • E06DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
    • E06CLADDERS
    • E06C7/00Component parts, supporting parts, or accessories
    • E06C7/42Ladder feet; Supports therefor
    • E06C7/46Non-skid equipment

Description

Oct. 24, 1961 c. E. LARSON 3,005,513 STEPLADDERS AND STRUCTURAL COMPONENTS THEREOF Filed March 25. 1959 2 Sheets-Sheet 1 INVENTOR. CLAYTON E LARSON M e/41m,
A TTORNE Y Oct. 24, 1961 c. E. LARSON 3,005,513
STEPLADDERS AND STRUCTURAL COMPONENTS THEREOF Filed March 25. 1959 2 Sheets-Sheet 2 INVENTOR. CLAYTON LARSON MM/QM,
ATTORNEY United States Patent 3,005,513 STEPLADDERS AND STRUtITURAL COIVHO- NENTS THEREQF Clayton E. Larson, Weston, COHXL, as'signor to White Metal Rolling 8; Stamping Corporation, Brooklyn,
N.Y., a corporation of New York Filed Mar. 25, 1959, Ser. No. 801,751 2 Claims. (Cl. 182-165) This invention relates to stepladders and structural components of ladders and is more particularly concerned with stepladders possessing the characteristics of structural and mechanical simplicity, light-weight, economy of manufacture and compactness for storage.
Field of invention There exists a real consumer demand for a stepladder providing structural simplicity, stability, minimal weight and compactness for storage and which does not include spreaders because of the attendant hazard of malfunction of spreader elements or collapse of a spreader retained ladder structure. Use of spreaders in ladders are also a problem because they contribute to increased bulk, multiplicity of manufactured units and difficulty in converting the ladder from a folded to an open position. Further, ladder spreaders present various problems of design and economy in the manufacture of stepladders.
A solution to this situation is provided by the present invention which offers a stepladder without the necessity for spreader means.
Another problem attendant upon the manufacture and use of ladders in general, lies in achieving an attachment between the steps and side rails of ladders which will resist both torsional and direct forces. This problem is pronounced in the fabrication of ladders from extruded light metals wherein the side rails and steps are commonly formed from light weight channel members. A remedy for this situation is offered by the present invention in which at novel tread and uniting arrangement provides a stronger connection and more stable structure.
Still another difficulty encountered in the fabrication of stepladders is that of uniting the front and rear sections by means which will allow pivotal movement between these sections while enduring considerable amounts of strain and wear. A novel lug member provided by the present invention provides a solution for this problem.
Objects A principal object of this invention is to provide new improvements in ladders. Further objects include: the decrease of material requirements for manufacture; provision for a ladder of structural simplicity; increased ease of manufacture as the result of the curtailment of the number of necessary structural units and assembly opera,- tions required; economic benefits resulting from the diminishing of assembly and material requirements; elimination of the possibility of mechanical malfunction present in stepladders utilizing spreader means; enhancement of stepladder storage characteristics; elimination of the difliculties presented by the setting up and folding of stepladders equipped with spreaders; provision of a strong and stable union between the steps and side rails of ladders in general and between the front and rear sections of stepladders, and enhancement of the tractive and cushioning support of ladders.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereafter. 'It should be understood, however, that the detailed description, while indicating preferred embodiments of the invention, is given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
General description These objects are accomplished according to the pres-,
ent invention by forming a stepladder comprising a front section, a rear propping section and uniting means which serves to pivotally attach the front and rear sectionsqin.
provides a stepladder structure which may assume a com-.
pact or folded position in which the side rails of the two sections are parallel, or the sections may be spread apart to form an acute angle. When the sections are spread in order to place the ladder in a} stable, independent posi tion for use, the upper ends of the rear section side rails, which are angular, abut upon the rear edges of the upper ends of the front section side rails, thereby acting as a stop means to limit the rotation of the front and rear sections about the point of pivotal attachment andeliminating the necessity for manipulation or adjustment of spreader means.
The uniting member by which the front and rear sections are connected is fashioned in the form of a lug with a projecting lateral flange which may be attached to the rear edge of the front section side rails. The upper ends of the rear section side rails are pivotally attached to the lug member which extends rearwardly of the front sec-.
tion side rails and the forward portion of the lug plate is fixed to the lateral surface of the front section side rail.- I Brace means are provided for the front and rear sec! tions. In the preferred form the front section is braced by means of elongate elements connecting the front edge.
of the front section side rails with the front, edge of the steps and the rear section is also reinforced by means Detailed description A more complete understanding of the'new devices of this invention may be had by reference to the accompanying drawings in which:
. FIGURE 1 is a perspective view of a preferred form of stepladder which is set up on position for use;
FIGURE 2 is a side View of the same ladder in a folded position; v
FIGURE 3 is a fragmentary, enlarged perspective view of an end portion of a step of the ladder;
, FIGURE 4 is an enlarged sectionalview of the lug 7 member and side rails taken along line URE 2;
FIGURE 5 is an enlarged, view of the step. and side'rail;
of FIG- fragmentary perspective FIGURE 6 is an end view ofa lug member of theladder; y v FIGURE 7 is a fragmentary side view ofthe foot member and side rail, and i FIGURE 8 is a fragmentary, sectional, end view of,
the bottom of a side rail and the attached foot member; Referring in detail. to the 'drawings, th eistepladder basically comprises a front section 2. which includes two Patented Oct. 24, 1961 In this side rails 4 with a plurality of space apart steps 6 and a top tread or platform 8 fixed between the side rails 4. 7 Attached to the upper ends of the front side rails 4 are lugmembers 10, described in more detail hereinafter, which are in turn pivotally attached at 1.2 to the side rails 14 of the rear propping section. The rear section side rails 14 are provided with angular upper ends 16 which abut upon the rear edge of the upper ends of the front section side rails when the ladder structure is in aspread or open position as illustrated in FIGURE 1.
- The rear section side rails 14 are also provided with two "or more bracernembers 1-8 which serve to hold the side rails 14 in a spaced-apart relation. In a preferred form wherein the side rails 14 are channel members comprising a central web and two spaced-apart laterally projecting flanges, one of the brace members 18- is attached at one end to the front flange of the left rear section side rail 14 near the top thereof and at the other end to the from flange of the right rear section side rail 14 near the bottom thereof. The second brace member 18 is attached at one end to the front flange of the night rear section side rail 14 near the top thereof and at the other end to the front flange of the left rear section side rail near thebot'tom thereof. The two brace elements are then attached, such as by rivets, to one another at their point of intersection. As shown in FIGURE 1, a second pair of brace members '19 may then be similarly attached to the rear flanges of the right and left rear section side rails 14.
Additional brace elements may also be provided in order to enhance the stability of the front section 2. The brace elements 20 may be attached at one end to the front edge of the side rail 4 at a point below the juncture of the side rail '4 and the bottom step 6, and at the other end to the front edge of the step 6 equal to the distance from this juncture to the point of attachment of the other end of the brace element to the side rail 4.
'- The stepladder may be converted to a compact folded form for'storage in which the front and rear sections are parallel as shown in FIGURE '2, by rotating the rear section side rails 14 about their point of pivotal attachment 12,'toward the front section side rails 4.
"A preferred form of step for use in the invention and in ladders in general is illustrated by FIGURES 3 and 5. The step comprises a channel member including a central web 2.2mm spaced-apart lateral projections 24 which are formed integrally with the web 6 and extend at an angle thereto. If desiredportions of the web 22 may be made to project beyond the flanges 24 as shown at 26 in FIGURE 5, by setting in the point of juncture of the flanges 24 with the central web 6. The end portions of the web 22- are provided with recesses 25 as shown in FIGURE 3, whereby the side rails, as shown by phantom lines in FIGURE 3, may be inserted in the recesses 25 and attached to the lateral flanges 24 of the step by rivets 3'2 which'extend through holes 30.
To enhance the tractive qualities of steps 6, their upper surfaces are provided with serrations 38' at the front and 7 rear edges.
The lug member used for pivotally uniting the front and rear ladder sections is illustrated by FIGURES 4 and 6, and comprises a flat plate and a laterally projecting flange 44 formed integrally therewith. In a preferred form the lug member is provided with a groove 42 along the point of juncture of the flange 44 and the plate 10 on the side of the flange which engages the front side rail 4. As shown in FIGURE 4, 'the'front side rail 4 is'attached to the plate 10 and the flange 44by means such as bolts or rivets. 34 and 36. The rear end of plate It) is attached to rear side rail 14 by pivotal means 12.
To prevent marring and provide a tractive support surfgce for the ladder structure, foot elements illustrated by FIGURES 7 and 8 are provided. For descriptive purposes the foot element is depicted in conjunction with front side rail 4. The foot elements comprise an L- shaped member 46 which is attached to the side rail 4 by rivet 52 and to secure a stronger attachment a groove 54 is provided adjacent to the vertical projection of the foot element 46 to receive the bottom of the side rail 4.
In the bottom surface of the horizontal projection of member 46, a resilient element 48 made of rubber or a similar substance, is inserted in the recess 56 and secured there by a rivet or similar means 50.
Having provided a complete description of the invention in such manner as to distinguish it from other inventions and from what is old, and having provided a description of the best mode contemplated of carrying out the invention, the scope of patent protection to be granted the invention is defined by the following claims.
I claim:
1. A stepladder comprising a front section including two side rails each comprising a central web, two spacedapart lateral projections formed integrally with said web which parallel the longitudinal axis of the Web and are normal to the web, means for connecting said two side rails in spaced-apart relation comprising a step including a central web, two spaced apart lateral projections formed integrally with said web which parallel the longitudinal axis of the web and project at an angle to the web, said central web being provided at each end with recesses spaced-apart a distance equal to the distance between said spaced-apart lateral projections of said side rails so that the lateral projections of the side rails may be inserted within the recesses provided in the central web of the step and attached to the lateral projections of the step, additional steps similarly fixed in a spaced-apart relation between said two side rails, a rear propping section comprising two side rails with angular upper ends, brace means for holding said rear section side rails in spaced-apart relation, means for pivotally attaching said rear section is said front section comprising a lug member carried near the top of one of the side rails of the front section and extending rearwardly of the rear edge of the side rail with one of the side rails of the rear section being pivotally connected thereto, a second lug member similarly attached to the other side rail of the front section and pivotally connected to the second side rail of the rear section, said lug members being spaced from the top of the front and rear section side rails so that the rear section side rails may be moved about the point of pivotal attachment to engage the angular upper ends of the rear section side rails with the rear edges of the front section side rails throughout a substantial extent of the angular surface and actingas the sole stop means for the rear propping section.
2. In a ladder having side rails comprising a central web and spaced-apart lateral projections formed integrally with the 'web, a step comprising a central web, two spaced-apart lateral projections formed integrally with said web which parallel the longitudinal axis of the web and project at an angle to the web, said central web being provided at each end with recesses spaced-apart a distance equal to the distance between said spaced-apart lateral projections of said side rail so that the lateral projections of the side rail may be inserted within the recesses provided in the end of the central web of the step and attached to the lateral projections of the step.
References Cited in the file of this patent UNITED STATES PATENTS UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent N05 3,,OO5,,513 October 24 1961 Clayton E. Larson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.
Column 4 line 36 for "is" read to Signed and sealed this 24th day of April 1962 (SEAL) Attest:
ESTON G. OHNSON DAVID La LADD Attesting Officer Commissioner of Patents
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Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3083786A (en) * 1961-09-19 1963-04-02 Bauer Mfg Company Stepladder
US3189123A (en) * 1962-05-11 1965-06-15 Homer L Bond Folding ladder
US3216526A (en) * 1961-12-18 1965-11-09 Racole Trading & Mfg Company L Ladders
US3327764A (en) * 1965-01-18 1967-06-27 Air Balance Damper and method of making same
US3327766A (en) * 1965-09-23 1967-06-27 Air Balance Damper frame
US3421598A (en) * 1966-10-11 1969-01-14 Showa Aluminium Co Ltd Combination ladder
US3782498A (en) * 1972-08-21 1974-01-01 R Gleisen Improved scaffold
US3882965A (en) * 1973-10-12 1975-05-13 Charles M Loomis Truck ladder
US4008786A (en) * 1975-09-15 1977-02-22 The Raymond Lee Organization, Inc. Support for elongated wooden planks and the like
US4332308A (en) * 1980-06-30 1982-06-01 White Metal Rolling & Stamping Corp. Safety stepladders
US4655320A (en) * 1984-12-14 1987-04-07 Benboid Pty Ltd. Ladder means and method of production
US4694932A (en) * 1986-08-12 1987-09-22 Emerson Electric Co. Structural support shoe and method of manufacturing the same
EP0345676A1 (en) * 1988-06-10 1989-12-13 Hailo-Werk Rudolf Loh GmbH & Co. KG Method for producing rungs for a step ladder
US5516127A (en) * 1993-07-20 1996-05-14 Guilford Glazer Cart for negotiating escalators
EP0691453A3 (en) * 1994-07-08 1996-08-14 Werner Co A ladder, member for connecting a rail to a horizontal element of a ladder, and method, and apparatus and method for holding a washer
US5636706A (en) * 1994-07-08 1997-06-10 Werner Co. Ladder, member for connecting a rail to a horizontal element of a ladder, and method
US6116379A (en) * 1997-11-12 2000-09-12 Michael A. Huss Ladder stabilizing cross brace
US20060231334A1 (en) * 2005-04-18 2006-10-19 Hall Bill R Stepladder stabilizer
US20110147123A1 (en) * 2008-09-27 2011-06-23 New-Tec Integration(Xiamen) Co.,Ltc. Top tread for aluminum ladder
US8191685B1 (en) * 2011-05-16 2012-06-05 Geiselman Iii Grover J Folding ladder
CN103362435A (en) * 2013-06-28 2013-10-23 河南省电力公司信阳供电公司 Anti-skidding ladder for electricians
USD710031S1 (en) 2012-11-15 2014-07-29 Tricam Industries, Inc. Step stool
US20140262621A1 (en) * 2013-03-15 2014-09-18 Hailo-Werk Rudolf Loh Gmbh & Co. Kg Step Ladder
US20140363228A1 (en) * 2013-06-10 2014-12-11 Constantine Vassilakos Ladder retaining bracket
US9068394B1 (en) 2014-10-10 2015-06-30 Grover J. Geiselman, III Space saving ladder
USD817516S1 (en) * 2017-04-05 2018-05-08 Louisville Ladder Inc. End cap for a ladder
US10066437B2 (en) * 2016-07-20 2018-09-04 The Boeing Company Staggered step trestle ladder
USD855833S1 (en) 2017-01-04 2019-08-06 Tricam Industries, Inc. Ladder rail
USD860476S1 (en) 2017-01-04 2019-09-17 Tricam Industries, Inc. Hinge for a multi-position ladder
US10808459B2 (en) * 2017-04-13 2020-10-20 Wing Enterprises, Incorporated Braces for ladders, ladders incorporating same and related methods

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US283524A (en) * 1883-08-21 Edwaed a
US791509A (en) * 1903-12-12 1905-06-06 John G Soergel Step-ladder.
US891736A (en) * 1905-05-24 1908-06-23 Chandelier & Art Brass Works Ladder.
US1479262A (en) * 1923-01-17 1924-01-01 Otto H Stegeman Stepladder
CH132565A (en) * 1928-12-01 1929-04-30 Mauch Robert Step ladder with extension piece that can be used as a substitute ladder.
GB555774A (en) * 1942-06-09 1943-09-07 Dorothy Jessop Marshall An improvement in or relating to step ladders
US2899008A (en) * 1955-09-21 1959-08-11 White Metal Rolling & Stamping Multi-way ladder

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US283524A (en) * 1883-08-21 Edwaed a
US791509A (en) * 1903-12-12 1905-06-06 John G Soergel Step-ladder.
US891736A (en) * 1905-05-24 1908-06-23 Chandelier & Art Brass Works Ladder.
US1479262A (en) * 1923-01-17 1924-01-01 Otto H Stegeman Stepladder
CH132565A (en) * 1928-12-01 1929-04-30 Mauch Robert Step ladder with extension piece that can be used as a substitute ladder.
GB555774A (en) * 1942-06-09 1943-09-07 Dorothy Jessop Marshall An improvement in or relating to step ladders
US2899008A (en) * 1955-09-21 1959-08-11 White Metal Rolling & Stamping Multi-way ladder

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3083786A (en) * 1961-09-19 1963-04-02 Bauer Mfg Company Stepladder
US3216526A (en) * 1961-12-18 1965-11-09 Racole Trading & Mfg Company L Ladders
US3189123A (en) * 1962-05-11 1965-06-15 Homer L Bond Folding ladder
US3327764A (en) * 1965-01-18 1967-06-27 Air Balance Damper and method of making same
US3327766A (en) * 1965-09-23 1967-06-27 Air Balance Damper frame
US3421598A (en) * 1966-10-11 1969-01-14 Showa Aluminium Co Ltd Combination ladder
US3782498A (en) * 1972-08-21 1974-01-01 R Gleisen Improved scaffold
US3882965A (en) * 1973-10-12 1975-05-13 Charles M Loomis Truck ladder
US4008786A (en) * 1975-09-15 1977-02-22 The Raymond Lee Organization, Inc. Support for elongated wooden planks and the like
US4332308A (en) * 1980-06-30 1982-06-01 White Metal Rolling & Stamping Corp. Safety stepladders
US4655320A (en) * 1984-12-14 1987-04-07 Benboid Pty Ltd. Ladder means and method of production
US4694932A (en) * 1986-08-12 1987-09-22 Emerson Electric Co. Structural support shoe and method of manufacturing the same
EP0345676A1 (en) * 1988-06-10 1989-12-13 Hailo-Werk Rudolf Loh GmbH & Co. KG Method for producing rungs for a step ladder
DE3819724A1 (en) * 1988-06-10 1989-12-14 Loh Kg Hailo Werk METHOD FOR PRODUCING STAGES FOR STEP LADDERS
US5516127A (en) * 1993-07-20 1996-05-14 Guilford Glazer Cart for negotiating escalators
US5560626A (en) * 1993-07-20 1996-10-01 Guilford Glazer Cart for negotiating escalators
US6142255A (en) * 1994-07-08 2000-11-07 Werner Co. Ladder, member for connecting a rail to a horizontal element of a ladder, and method
EP0691453A3 (en) * 1994-07-08 1996-08-14 Werner Co A ladder, member for connecting a rail to a horizontal element of a ladder, and method, and apparatus and method for holding a washer
US5791439A (en) * 1994-07-08 1998-08-11 Werner Co. Ladder, member for connecting a rail to a horizontal element of a ladder, and method, and apparatus and method for holding a washer
US5636706A (en) * 1994-07-08 1997-06-10 Werner Co. Ladder, member for connecting a rail to a horizontal element of a ladder, and method
US6116379A (en) * 1997-11-12 2000-09-12 Michael A. Huss Ladder stabilizing cross brace
US20060231334A1 (en) * 2005-04-18 2006-10-19 Hall Bill R Stepladder stabilizer
US20110147123A1 (en) * 2008-09-27 2011-06-23 New-Tec Integration(Xiamen) Co.,Ltc. Top tread for aluminum ladder
US9926742B2 (en) * 2008-09-27 2018-03-27 New-Tec Integration (Xiamen) Co., Ltd. Top step for aluminum ladder
US8191685B1 (en) * 2011-05-16 2012-06-05 Geiselman Iii Grover J Folding ladder
USD710031S1 (en) 2012-11-15 2014-07-29 Tricam Industries, Inc. Step stool
US20140262621A1 (en) * 2013-03-15 2014-09-18 Hailo-Werk Rudolf Loh Gmbh & Co. Kg Step Ladder
US20140363228A1 (en) * 2013-06-10 2014-12-11 Constantine Vassilakos Ladder retaining bracket
CN103362435A (en) * 2013-06-28 2013-10-23 河南省电力公司信阳供电公司 Anti-skidding ladder for electricians
US9068394B1 (en) 2014-10-10 2015-06-30 Grover J. Geiselman, III Space saving ladder
US10066437B2 (en) * 2016-07-20 2018-09-04 The Boeing Company Staggered step trestle ladder
USD855833S1 (en) 2017-01-04 2019-08-06 Tricam Industries, Inc. Ladder rail
USD860476S1 (en) 2017-01-04 2019-09-17 Tricam Industries, Inc. Hinge for a multi-position ladder
USD817516S1 (en) * 2017-04-05 2018-05-08 Louisville Ladder Inc. End cap for a ladder
US10808459B2 (en) * 2017-04-13 2020-10-20 Wing Enterprises, Incorporated Braces for ladders, ladders incorporating same and related methods

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