US2678831A - Retractable ladder construction for trailers - Google Patents

Description

May 18,1954 v A. E. FISHER 2,678,331

RETRACTABLE LADDER CONSTRUCTION FOR TRAILERS Filed March 26, 1951 2 Sheets-Sheet 1 y 8, 1954 A. E. FISHER 2,678,831

RETRACTABLE LADDER CONSTRUCTION FOR TRAILERS Filed March 26, 1951 V 2 Sheejzs-Sheet 2 firm/avers.

Patented May 18, 1954 RETRACTABLE LADDER CONSTRUCTION FOR TRAILERS Albert E. Fisher, Indianapolis, Ind. Application March 26, 1951, Serial No. 217,506

2 Claims. 1

This invention relates to a retractable'ladder for automotive vehicles and more particularly for trailers and the like.

It is the primary object of this invention to provide a ladder of such character and construction that access may be had through its use to the interior of the vehicle. The distance above the ground of the bed of vehicles such as trailers and the like is, of course, considerable. When loading equipment, supplies or material it is necessary that some means be used to span or bridge the distance. The present invention serves that purpose.

It is a further object of the invention to provide a ladder of such character and construction that it may be moved with ease to an outof-the-way position underneath the vehicle bed upon its having served its purpose. Most of the conventional ladders used in connection with such vehicles have a folding step that hangs downwardly approximately 17 inches below the frame or the bed when in the non-use position. As a consequence they are constantl being sheared or knocked off. Applicants ladder on the other hand extends downwardly only about 4 inches, thereby presenting a much less exposed portion, and consequently eliminating or at least appreciably reducing, the dangers of its being sheared off.

It is a still further object of the present invention to provide a ladder which will be retained in its non-use position without the use of springs or other devices. As is well known, it is difficult to moor constructions of this character in their non-use position without providing latching or like means which not only add to the expense and to the number of parts needed, but as well limit the ease with which the ladder may be used. With the present invention there is no need for employing any latching mechanism, as will be shown and described hereinafter.

It is a still further object of this invention to provide a particular type of guide and roller means by which the ladder may be swung from its non-use to its use position and vice versa.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

In the drawings:

Fig. l is a perspective view showing a portion of the frame of a trailer with the invention shown in its use position.

Fig. 2 is a perspective View from underneath the trailer of the invention in its use position.

Fig. 3 is a side elevation view of the invention with a portion or" the trailer frame shown in section, the non-use position of the invention being indicated by dotted lines.

Fig. is a front elevation view of the lower step of the ladder and its support, when in its non-use position, the ladder sides being shown in section.

Fig. 5 is a front elevation view of the ladder roller construction with the ladder sides and the ladder guideways in vertical section.

In the drawings, the trailer with which the invention is associated is shown generally at In, it being supported at its front end when not in use by the dolly wheels H connected to the support leg 12 which is telescopically associated with the member l3. Supporting the leg and .connected to the collar I4 are the radius or bracing rods in secured at It to the frame I! of the trailer. Depending from the sides of the trailer are the frame members It. Extending transversely of the bed It are the bracing struts or cross members 2-5). All of the above elements and members are conventional.

The invention itself consists of the downwardly inclined parallel guide rails 2| which are preferably although not necessarily formed of spaced LI-shaped channel bars. A portion is struck out longitudinally of the bars to form the aligned slots or guideways 22. The inner, lower end of each of the bars is connected to at least one of the cross members 20 through the medium of the angle iron 23. The base 24 of this angle iron is secured by welding or the like to the upper flange of the U-shaped bars. The angle iron is itself secured to an upwardly inclined angle iron 25 by bolts 26 or other suitable means,

'while the angle iron 25 is secured in any suitable manner such as by the bolts 21 to one side of cross member 29. It is to be understood that any satisfactory method of supporting the inner, lower ends of the U-shaped bars may be employed.

It is to be observed that the lower sides of each of the U-shaped bars depends downwardly from the bottom side of the cross members 2!) a distance of approximately 4 inches. As a result, the entire construction is in such close proximity to the cross members 20 and to the bed of the trailer that the possibilities of its being sheared or knocked on" in transit are appreciably reduced, if not entirely eliminated.

The outer, upper end of each of the U-shaped bars is secured in any suitable manner to the member 28 which itself is secured in any suitable manner to the under surface of the bed It. As a result of this arrangement and construction the guideways are downwardly and inward- 1y inclined from the side frames of the trailer at angle of approximately 25 degrees. While the angle of inclination is in and of itself not critical, it is highly desirable that it approximate the above'mentioned degree in order that the lover side or surface of the U-shaped bars not extend more than approximately 4 inches below the lower side of the cross members 20. It will be observed that the outer, upper ends of the U-shaped bars are disposed inwardly a slight distance from the side frame I8 of the trailer.

The ladder itself consists of any suitable side arms such as angle irons' 29 along with steps 39.

The steps themselves may be formed of metal if Fig. 3 is substantially U-shaped. These hangers include the upwardly and inwardly inclined fulcrum' bearing surfaces 3'4 upon which the lower flanges of the ladder sides are freely 'slidabl'e. Integral with the upper extremity of each surface .34 of the hangers is the depending back wall portion 35, the lower extremity of which terminates in an inwardly extending ledge portion '36. The ledges :are in substantially the same vertical plane as. the side arms of the ladder which rest thereupon. The hanger also includes outer side wall portions 36a. With this construction it is possible, after the ladder has been moved from its use to its non-use position to nest the outer 'end of the ladder within the pocket 31 formed by the ledge portion 36, the back wall portion 35 and the side wall portion 36a. Thus, once the ladder is in its non-use position-as shown in dotted lines in Fig. 3, it is prevented from any lateral or longitudinal movement. It is possible for it to be. moved to its use position only after the free, end 1580f the ladder is first lifted upwardly toan'extentsufiicient to clear the back wall portion '35 of the hanger.

The upper extremity of the ladder .is provided with a roller construction which assures that the ladder will always be in operable condition. This constructionincludes the bolt 39 having a head 40 which projects through the slot 22 and through an aperture 1H formed in the side arms of the ladder; The roller itself consists of the tubular member 4-2 which envelopes the shank of the bolt 38. Disposed in slightly spaced relation on either side of the roller in order to permit its free rotation are the washers 43. In or der to retain the bolt head in the same relative positiorrto the side arm of the ladder so that the roller will alwys be freely rotatable, there is provided a nut 44 which is welded at 45 to the inner face of the ladder side arm. A locking nut 48 isthen. secured about the shank of the bolt in abutting position to the welded nut. sequence of this cons ruction the roller is always capableof free rotation so that it may ride with ease-upon the tracks 2! defining the slots 22.

When access to the side door of the trailer, indicated generally at 48, is desired, the ladder may readily be moved from .its non-use to its use position. This is accomplished by first lifting upwardly on the :free end 38 of the ladder until it clears the depending or back wall portion 3-5 of the hanger, whereupon the free end may be pulled outwardly and then downwardly to its use position. The ladder side arms bear upon the fulcrum bearing portions intermediate their ends. When the reverse is desired it is necessary only to lift upwardly on the free end of the ladder and apply force inwardly as a re sult of which the roller end of the ladder will ride downwardly with ease upon the guideway.

When the roller end reaches the end of the slot it will, of course, be stopped whereupon the free end of the ladder may be nested within the pocket 31 formed by the hanger ledge 36 and the depending or back wall portion 35. When in the nested position it is obvious that it will withstand the bouncing and bumping that attends the'movement of the trailer along the highway and; that it will retain that position. As mentioned before, any longitudinal movement of the ladder will be'prevented by the back wall of the pocket. Any sideways or lateral movement will be prevented by the hanger side walls; and the roller end of the ladder; will be prevented from vertical displacement by the guideways.

While the. invention has been illustrated and described in great detail in the drawings and foregoing description, the same is to be considered; as illustrative and not restrictive in character.

The invention claimed. is:

1. In a motor vehiclea. retractable ladder construction comprising a pair of parallel spaced inwardly directed and downwardly inclined elongated guideways secured to the under portion of said vehicle, the outer ends thereof being spaced inwardly of one side. of said vehicle, a ladder having roller means operably slidabl'e within said guideways whereby said ladder may be moved to and from a retracted osition under said vehicle and an extended use position, and a pair of opposed hanger supportsnf'onsaid ladder connected to the under portion of said vehicle adjacent said one side thereof and in. spaced relation to said guideways, each of said hanger supports each including an upwardly and inwardly inclined fulcrum bearing surface .for the side arms of said ladder, said surface being integral. at its inner end with a substantially right angular member adapted to serve as a pocket within which one end of said ladder may be nested when :in its retracted position.

2. In a motor vehicle, 'a retractable ladder construction comprising a pair of parallel spaced inwardly directed and downwardly inclined elongated guideways secured to the under portion of said vehicle, a ladder operairlvely associated with said .guid'eways and having. means freely 'slidab'le therewithin whereby said ladder is movable to and from a retracted position under said vehicle and an extended use position, and a pair of opposed hanger supports for said ladder, they being connected to the under portion of said vehicle adjacent one side thereof and in spaced relation to said guideways, each of said hanger supports including an upwardly and inwardly inclined fulcrum bearing surface for the side arms of said ladder, said surface being integral at its inner end with a substantially right angular member adapted to serve as a pocket within which one end of said ladder may be nested when in its retracted position, and at least one side wall connected to each of said members for preventing lateral movement of said ladder.

References Cited in the file of this patent UNITED STATES PATENTS Number

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