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Patent: A Better Ladder For Your Motor Home
Patent: A Better Ladder For Your Motor Home | mid_txbz, odess_txbz, Andrews, Robert Gail Stewart, James Edward Stewart, 8215452, extendable ladder, trailer, Motor home, vehicle,

Robert Gail Stewart and James Edward Stewart, both of Andrews, Texas, recently received U.S. Patent 8,215,452 for “Extendable Ladder for Trailer, Motor Home or Other Vehicle.”

Texas Business Patent of the Day:  Two Texas men have invented a better ladder for your motor home or trailer.

Robert Gail Stewart and James Edward Stewart, both of Andrews, Texas, recently received U.S. Patent 8,215,452 for “Extendable Ladder for Trailer, Motor Home or Other Vehicle.”

The two men applied for the patent almost five years ago on December 14, 2007.

The invention relates to extendable ladders mounted to trailers, motor homes and the like for providing improved safety and ease when accessing the roof of the trailer or vehicle. 

The Stewarts observed a need for improving the safety and ease by which individuals access the roof or top of a vehicle, for example, to remove hay or other objects from a horse trailer, to access items on top of a motor home, and the like. In general, current trailers and motor homes typically have a ladder mounted to a side or rear wall of the vehicle. The ladder includes a frame with upper ends and lower ends that mount to the wall. As a result, the frame is approximately vertical and does not extend to the ground. The prior art discloses numerous other methods of mounting ladders to objects such as vehicles. 

 It also is known to use mobile or portable stairs that have two sections that move relative to each other to allow one portable stair apparatus to be used with platforms of different heights. These portable stairs can be used in numerous applications, for example, in warehouses and box stores to access items stored on high shelves and in the chemical and oil industry to access platforms on chemical processing equipment and oil wells. These portable stairs generally are not permanently fixed to the platform or shelf but instead are moved around as needed to access the elevated shelves or platforms. 

Other portable stairs provide the user the ability to purchase one portable stair apparatus and use it with different applications, e.g., a worker in the oil drilling industry may take this from one oil drilling platform to another as need. Thus, the worker may leave the portable stair apparatus on a particular oil drilling platform for one day or months at a time. Notably, the stair apparatus is not permanently fixed or mounted to the platform but instead is retained to the platform by using hooks that clip onto the platform. 

These stairs are regulated by the Occupational Safety and Health Administration (OSHA) at 29 CFR 1910.29 (Manually Propelled Mobile Ladder Stands and Scaffolds (Towers)) (2007), which requires that the slope of the steps section be between a minimum of 55 degrees and a maximum of 60 degrees measured from the horizontal. In contrast, OSHA regulations at 29 CFR 1910.24 (2007) for fixed stairs require the angle of the stairway rise to be between 30 degrees and 50 degrees measured from the horizontal. It should be noted that because such stairs are used at a slight angle, it is not typically a problem for the two sections to slide past each other. For example, if the stairs including of sliding sections that are made of aluminum, the two sliding sections will be expected to slide past each other with relative ease and avoid the binding or catching that would be expected if the two sliding sections were at a more extreme angle. 

The Stewarts’ invention provides an extendable ladder configured to extend a second ladder segment relative to a first ladder segment. The ladder includes a first ladder segment, a second ladder segment, and at least two slider cups. 

The first ladder segment includes two beams and each beam includes at least a first leg and a second leg with the first leg and the second leg being joined lengthwise to form an angle between the first leg and the second leg. One or more rungs are connected to and extend between the first leg of the first beam and the first leg of the second beam. One or more mounting arms extend from the beams with the mounting arms being configured at one end to be permanently mounted to a surface and being pivotally attached at another end to the beam whereby the beams can pivot with respect to the mounting arms to vary an angle formed between the mounting arm and the beam. 

The second ladder segment includes two beams and each beam includes at least a first leg and a second leg with the first leg and the second leg being joined lengthwise to form an angle between the first leg and the second leg. One or more rungs are connected to and extend between the first leg of the first beam and the first leg of the second beam. 

The slider cups are mounted to either or both of the first ladder segment and the second ladder segment and include a first wall and a second wall being positioned in parallel planes and connected by at least a third wall passing through a plane generally perpendicular to the first and second walls. The first wall is mounted to either or both of the first leg and the second leg of one beam with the third wall being adjacent to the second leg of the one beam. The second wall is positioned in a plane parallel to the second leg of the one beam and being separated from the second leg by a gap. The second leg of an adjacent beam is positioned within the gap between the second leg of the one beam and the second wall of the slider cup, 

In this manner, when the mounting arms are mounted to a surface and the ladder is in a generally directly vertical orientation, extending the second ladder segment relative to the first ladder segment causes the second leg of the adjacent beam to slide within the gap formed by the slider cup and the ladder can be moved from a generally vertical orientation to an angled orientation of between at least 60 degrees and approximately 90 degrees measured from the horizontal. 

Embodiments of the extendable ladder may include one or more of the following features. For example, the extendable ladder can move between the generally vertical orientation and an orientation that is between greater than 75 degrees and approximately 90 degrees measured from the horizontal. The extendable ladder can move between a generally vertical orientation and an orientation of between approximately 70 degrees and 75 degrees measured from the horizontal when the mounting arms are mounted to the surface. 

The angle between the second leg and the first leg may be approximately 90 degrees. The beams may further include a third leg and the angle between the third leg and the first leg is approximately 90 degrees. 

One or more of the beams and slider cups may made of aluminum. The slide cups may further include a fourth wall connected at a first edge and extending from the first wall in the direction of the second wall such that the gap is formed between a second edge of the fourth wall and the second wall. The fourth wall may have a third edge adjacent to the third wall and a fourth edge generally parallel to the third edge and being adjacent to the first wall. 

The extendable ladder may further include one or more spacers mounted to the beams and configured to limit the movement of the second segment when extending the second segment relative to the first segment. 

The mounting arms may be one or more of generally L-shaped, T-shaped, and linear. The mounting arms may be mounted to one or more of a vehicle, a building, and a piece of equipment. The vehicle may be one or more of a trailer, recreational vehicle, truck, and bus. 

In another general aspect there is provided a method of using a ladder to obtain access to an upper portion of a vehicle. The method includes providing a ladder, pivoting the ladder, and extending the ladder. The ladder includes a first ladder segment, a second ladder segment, and at least two slider cups. 

The first ladder segment includes two beams and each beam includes at least a first leg and a second leg with the first leg and the second leg being joined lengthwise to form an angle between the first leg and the second leg. One or more rungs are connected to and extend between the first leg of the first beam and the first leg of the second beam. One or more mounting arms extend from the beams with the mounting arms being configured at one end to be permanently mounted to a surface and being pivotally attached at another end to the beam whereby the beams can pivot with respect to the mounting arms to vary an angle formed between the mounting arm and the beam. 

The second ladder segment includes two beams and each beam includes at least a first leg and a second leg with the first leg and the second leg being joined lengthwise to form an angle between the first leg and the second leg. One or more rungs are connected to and extend between the first leg of the first beam and the first leg of the second beam. 

The slider cups are mounted to either or both of the first ladder segment and the second ladder segment and include a first wall and a second wall being positioned in parallel planes and connected by at least a third wall passing through a plane generally perpendicular to the first and second walls. The first wall is mounted to either or both of the first leg and the second leg of one beam with the third wall being adjacent to the second leg of the one beam. The second wall is positioned in a plane parallel to the second leg of the one beam and being separated from the second leg by a gap. The second leg of an adjacent beam is positioned within the gap between the second leg of the one beam and the second wall of the slider cup. 

In this manner, when the mounting arms are mounted to a surface and the ladder is in a generally directly vertical orientation, extending the second ladder segment relative to the first ladder segment causes the second leg of the adjacent beam to slide within the gap formed by the slider cup and the ladder can be moved from a generally vertical orientation to an angled orientation of at least 60 degrees and approximately 90 degrees measured from the horizontal. 

In the method, pivoting the ladder away from the vertical surface of the vehicle includes pivoting the ladder such that there is an angle of between greater than 60 degrees and approximately 90 degrees between the ladder and the vertical surface of the vehicle. 

Extending the ladder includes extending the second ladder segment relative to the first ladder segment until the second ladder segment reaches the ground. Extending the second ladder segment causes the first beam of the second ladder segment to slide through the gap formed in the slider cup mounted to one or both of the first ladder segment and the second ladder segment. 

Embodiments of the method may include one or more of the following features or those described above. For example, the mounting arms may be attached to a surface of the vehicle. One or more of the beams and the slider cups may be made of aluminum. 

The ladder may be moved away from the vertical surface of the vehicle such that there is an angle of between approximately 75 degrees and 90 degrees from the horizontal. 

Storing the ladder may include moving the second ladder segment relative to the first ladder segment to decrease a total length of the extended ladder and so doing cause the first beam of the second segment to slide through the gap formed in the slider cup mounted to one or both of the first ladder segment and the second ladder segment. 

In another general aspect there is provided a vehicle to which the extendable ladder disclosed herein is mounted with the mounting arms being mounted to a vertical surface of the ladder. Embodiments of the vehicle may include one or more of the features described above. For example, the vehicle may include one or more of a truck, trailer, recreational vehicle, and bus.