US1028691A - Combined step and extension ladder. - Google Patents

Description

J. DUNCAN. COMBINED STEP AND EXTENSION-LADDER.

APPLICATION FILED SEPT. 30, 1911.

' Patented June 4,1912.

2 SHEETS-SHEET 1.

J. E. DUNCAN.

COMBINED STEP AND EXTENSION LADDER.

APPLICATION FILED SEPT. 30', 1911.

- Patented June 4, 1912.

2 SHEETS-SHEET 2.

wi tmaooao FCE.

JAMES E. DUNCAN, OF ELTON, LOUISIANA.

COMBINED STEP AND EXTENSION LADDER.

To all whom it may concern:

Be it known that I, JAMES E. DUNCAN, a citizen of the United States, residing at Elton, in the parish of Calcasieu and State of Louisiana, have invented a new and useful Combined Step and Extension Ladder, of which the following is a specification.

The invention relates to improvements in combined step and extension ladders.

The object of the present invention is to improve the construction of extension step ladders, and to provide a ladder of this character, which will be cheap to manufacture, and capable of being readily arranged to for either a step ladder or an extension ladder, and being securely locked in its extended position.

With these and other objects in view, the invention consists in the construction and novel combination of parts hereinafter fully described, illustrated in the accompanying drawings, and pointed out in the claims hereto appended; it being understood that various changes in the form, proportion, size and minor details of construction, within the scope of the claims, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

. tive view of a ladder, constructed in accordance with this invention, the parts being arranged to form a step ladder.- Fig. 2 is a side elevation, the parts being arranged to form an extension ladder. Fig. 3 is a longitudinal sectional View on the line 33 of Fig. 2. Fig. 4 is' a longitudinal sectional view on the line H of Fig. 3.

Like numerals of reference designate corresponding parts in all the figures ofthe drawings. I

In the accompanying drawings in which is illustrated the preferred embodiment of the invention, the combined step and extension ladder comprises in its construction a front section 1 and a prop or extension sec tion 2, pivotally connected with the front section 1 and adapted to be arranged in an inclined position at an angle thereto to form a step ladder, as illustrated in Fig. 1 of the drawings, and capable of being swung upwardly or outwardly into the plane of the front section to form an extension thereof,

Specification of Letters Patent.

Application filed September 30, 1911.

Patented June 4, 1912.

Serial No. 652,215.

as illustrated in Fig. 2 of the drawings. The front section is preferably composed of side bars 3 and connecting steps 4, suitably secured to the side bars 3. The rear prop or extension section 2 is preferably composed of side bars 5 and connecting rungs 6, suitably secured at their ends to-the side bars 5, but the extension or prop section 2 may be constructed in any other suitable manner, and the front section may be provided with rungs instead of steps if desired.

The side bars 5 of the extension or prop section are pivoted at their upper ends to the outer faces of the side bars 3 of the front section 1 by means of a transverse pivot rod 7, which pierces the side bars 3 at the upper portions thereof at a point adjacent to the lower face'of the second step. The pivot rod is equipped at its ends with nuts 8, washers 9 being interposed between the nuts and the outer faces of the side bars 5 of the extension or prop section 2. Any other suitable means may be employed for pivoting the upper ends of the side bars 5 of the extension or prop section 2 to the side bars 3 of the front section 1.

When the parts are arranged to form a step ladder, as illustrated in Fig. 1 of the drawings,'the sections of the ladder are secured in their angular relation by means of braces 10, consisting of metallic bars pivoted at their rear ends to the outer faces of the side bars 5 of the rear section 2 by means of a transverse pivot rodll, having threaded terminals piercing the side bars 5 and extending through the braces 10 and receiving nuts 12, washers 13 being preferably interposed between the inner faces of the braces and the outer faces of the side bars 5. The front ends of the braces 10 are provided with openings 14: to receive extended ends 15 of a transverse rod 16, located beneath the second step from the bottom and piercing the side bars 3 and secured to the-section 1 by nuts 17, arranged on the threaded ends 15 at the outer faces of the side bars 3 and interposed between the sidebars 3 and the inner faces of the braces 10. The extended ends 15 of the transverse rod 16 are provided with transverse perforations 18 for the reception of keys 19 for detachably securing the free front ends of the braces 10 on the extended terminals 15 of the rod 16.

Any other means, however, may be employed for detachably securing the front ends of the braces to the front section 1, when the parts are arranged to form a step ladder.

The side bars 3 of the front section 1 are provided in their upper ends with recesses 20 for the reception of a loose locking rod 21, carried by the extension or prop section 2 and mounted on short longitudinal slots 22 in the side bars 5 and movable along the slots 22 to engage and disengage the recessed upper ends of the side bars 3. The slots 22 are spaced from the pivoted upper ends of the side bars 5 a sufficient distance to enable the loose locking rod 21 to be moved into and out of engagement with the recess 20 of the side bars 3, when the rear prop or extension section of the ladder is arranged in the plane of the front section 1 to form an extension ladder, and when the locking rod is in engagement with the recesses 20, the prop or extension section 2 is held against pivotal movement on the ends of the rod 7. The side bars 3 are rounded at their upper edges 23 in rear of the recesses 20 to enable the locking rod to ride readily over the upper ends of the side bars 3 in engaging the recesses 20, and the upper ends of the said side bars 3 are extended at 24: at the front walls of the recesses 20 to form stops to prevent the prop or extension section from swinging forwardly out of alinement with the front section 1. The top step of the front section 1 is provided in its upper face with a longitudinal groove 25, which receives the loose locking rod when the same is in engagement with the recesses 20 to permit the locking rod to lie below the plane of or in substantially flush relation with the upper face of the top step, so that the feet of a person using the ladder. will not come in contact with the locking rod.

The loose locking rod 21 is provided with threaded terminals 26, extending beyond the outer faces of the side bars 5 and receiving nuts 27 for retaining the locking rod in the slots 22. The threaded terminals 26 of the locking rod are also provided with transverse perforations 28 for the reception of pins or keys 29 for securing the free ends of the braces 10 on the extended terminals of the locking rod. The braces 10 extend downwardly from the pivot rod 11 when the extension or prop section is in an upright position to form an extension ladder, and the said braces 10 are of a length to extendto the loose locking rod when the ladder is in engagement with the recesses 20 and the openings 14 in the free ends of the braces 10 are adapted to be placed over or arranged on the extended terminals of the loose locking rod, whereby the ladder is held against upward or outward movement in the slots 22 to retain the locking rod 21 in engagement with the recesses 20 of the side bars 3 of the front section. By this construction the means for bracing the parts when the same are arranged in an inclined position to form a step ladder, serves also as the means for positively holding the looking rod of the rear prop section in engagement with the front section, when the parts are arranged to form an extension ladder, and there is no liability of the sections accidentally folding or collapsing.

Having thus fully described my inven tion, what I claim as new and desire to secure by Letters Patent, is z.-

1. A ladder of the class described comprising. a front ladder section provided in the upper -ends of its side bars with recesses, a rear ladder section pivoted at the upper ends of its side bars to the front ladder section at a point intermediate of the ends thereof'and adapted to be arranged in an inclined position to provide a step ladder and in an upright position to form an extension of the front section, said rear section being provided in its sidebars with slots, a loose locking rod extending across the rear section and operating in the slots and adapted to engage the recesses of the side bars of the front section when the parts are arranged to form an extension ladder, braces pivoted at their rear ends to the rear ladder section, means for securing the front ends of the braces to the front ladder section when the parts are arranged to form a step ladder, and means for also securing the free front ends of the braces to the ends of the locking rod for holding the latter in engagement with the said recesses when the parts are arranged to form an extension ladder.

2. A ladder of the class described including a front ladder section provided in the upper ends of its side bars with recesses having extended front walls forming stops, said front ladder section being also provided in its top step witha groove arranged at the lower ends of the said recesses, a rear ladder section provided in its side bars with slots located intermediate of the ends'of the rear section, the upper ends of the side bars thereof being pivoted to the side bars of the front section below the said recesses. to permit the rear section to be arranged at an angle to the front section to form a step ladder and at an angle to the the ends of the locking rod to retain the In testimony that I claim the foregoing ladder in engagement with the recesses as my own, I have hereto aflixed my signa- When the parts are arranged to form an exture in the presence of tWo Witnesses.

tension ladder, and means mounted on the JAMES E. DUNCAN. front section for engaging the openings in Witnesses:

the free ends of the braces When the parts F. E. POWELL,

are arranged to form a step ladder. E. O. POWELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0.

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