Patent Application
20130327593
The present invention relates to ladders. More specifically, the present invention is related to an improved double-sided step ladder having steps with staggered spacing relative to each side of the step ladder and which may be of particular use to craftsmen and workmen in general.
Step ladders are free-standing ladders that can be erected without support from a wall, and can be folded together under transport. A step ladder may consist of a frame with steps, or step frame, which is pivotally attached to a smaller support frame. Step ladders constructed in this manner are commonly called single-sided step ladder. A double-sided step ladder (also called a two-sided or twin ladder) may also consist of two frames pivotably attached to each other, however, both frames include steps.
Double-sided step ladders currently available on the market vary in height, typically ranging from 4 ft. to 20 ft., and include a plurality of evenly spaced steps. The steps are typically spaced about 1 ft. apart with the first step being about 1 ft. above the base of the ladder. Thus, for example, a 6 ft. double-sided step ladder will usually include 5 steps per side with an upper step common to both sides. Similarly, an 8 ft. ladder will have 7 steps per side with a common upper step.
In addition to being pivotably attached adjacent the upper step, the two frames of the double-sided step ladder are connected by a locking mechanism that prevents the step ladder from collapsing. Additionally, a small tray, sometimes called a utility tray, may be fastened to the ladder for holding tools, parts, paint etc., a feature that allows a workman to avoid time-consuming climbing up and down of the ladder.
The opposing steps on the two pivotably attached frames of a double-sided step ladder are generally parallel to each other. In other words, the first steps on the two pivotably attached frames will both be about 1 ft. above the base of the ladder with each successive step being spaced apart an additional 1 ft. up both frames. Thus, a double-sided step ladder can be ascended from either side to provide access to an elevated work site.
Often the elevated work site being accessed by a workman using a double-sided ladder is at a height that makes it uncomfortable for the workman to perform a task. Because the steps are spaced at about 1 ft. apart, the workman may have to choose to stand on a step which is slightly too low, thus causing the workman to stretch his or her body to reach the work site. The only alternative may be to stand on the next highest step, which may be slightly too high, causing the workmen to perform tasks in a crouched position. Either choice makes it more difficult for a workman to perform a task at the elevated work site, especially for an extended period of time. Additionally, the workman may fatigue more rapidly working in an extended or crouched position, thus making it more likely that he or she will have an accident while performing a task at the elevated work site.
In recent years telescopic and adjustable ladders have come to market. However, telescopic and adjustable ladders typically have complicated adjustment mechanisms and include a large number working components to function properly. This may cause these types of ladders to feel unstable and/or cause these types of ladders to be relatively heavy and more expensive as compared to a typical double-sided step ladder. Furthermore, use of telescopic and adjustable ladders may increase the time it takes to perform a task at an elevated work site because of the necessity to make the proper height adjustment. The adjustment mechanisms of telescopic and adjustable ladders may also become easily jammed by paint, glue, sand, concrete, etc. that is spilled in the mechanism. Thus, a workman may be further delayed trying to repair the ladder prior to safely using the telescopic or adjustable ladder. In comparison, a step ladder, such as a double-sided step ladder, can be easily and quickly erected due to their uncomplicated locking mechanism.
There is thus a need for an improved double-sided step ladder which can be used for extended periods of time at an elevated work site in safer and better ergonomic conditions.
It is an object of the present invention to provide an improved double-sided step ladder.
According to one aspect of the invention a double-sided step ladder may include a first frame and a second frame each having a plurality of spaced apart steps. The first frame may include a bottom step located at a first height relative to the base of the ladder with each successive step being spaced apart along the frame at various heights relative to the bottom step of the first frame. The second frame may also include a bottom step, the bottom step of the second frame being located at a second height relative to the base of the ladder with each successive step being spaced apart along the frame at various heights relative to the bottom step of the second frame. The plurality of steps on the first frame and the second frame may be located such that the heights of the plurality of steps on the first frame are staggered relative to the heights of the plurality of steps on the second frame.
According to another aspect of the invention, the plurality of steps on at least one of the first frame and the second frame are located in evenly spaced apart increments.
According to another aspect of the invention, the plurality of steps on both the first frame and the second frame are located in evenly spaced apart increments so that the steps on the first frames are evenly staggered relative to the steps on the second frame.
According to another aspect of the invention, the bottom step of the first frame may be located at about 6 inches from the base of the ladder with each successive step being spaced apart in 1 ft. increments along the first frame relative to the bottom step of the first frame. The bottom step of the second frame may be located at about 1 ft. from the base of the ladder with each successive step being spaced apart in about 1 ft. increments relative to bottom step of the second frame.
According to another aspect of the invention, a support plate may be attached to at least one of the first frame and the second frame.
These and other aspects of the present invention are realized in an improved double-sided step ladder as shown and described in the following figures and related description.
Various embodiments of the present invention are shown and described in reference to the numbered drawings wherein:
It will be appreciated that the drawings are illustrative and not limiting of the scope of the invention which is defined by the appended claims. The embodiments shown accomplish various aspects and objects of the invention. It is appreciated that it is not possible to clearly show each element and aspect of the invention in a single figure, and as such, multiple figures are presented to separately illustrate the various details of the invention in greater clarity. Similarly, not every embodiment need accomplish all advantages of the present invention.
The invention and accompanying drawings will now be discussed in reference to the numerals provided therein so as to enable one skilled in the art to practice the present invention. The drawings and descriptions are exemplary of various aspects of the invention and are not intended to narrow the scope of the appended claims.
Turning now to
The first frame 20 may include a plurality of spaced apart steps 25a-e located at various heights along the first frame 20. The bottom step 25a may be attached to the first frame 20 at a first height relative to the base of the ladder 10 (e.g. the bottom ends 22, 32 of the first and second frame 20, 30, respectively). For example, the bottom step 25a may be attached to the first frame 20 so that it is about 1-12 inches above the base of the ladder 10. Each additional step 25b-e may be attached to the first frame 20 at various heights relative to the bottom step 25a. For example, step 25b may be about 1 ft. above bottom step 25a and step 25c may be about 1 ft. above step 25b, etc.
Similarly, the second frame 30 may include a plurality of spaced apart steps 35a-e located at various heights along the second frame 30. The bottom step 35a may be attached to the second frame 30 at a second height relative to the base of the ladder 10. According to principles of the present invention, the second height of the bottom step 35a of second frame 30 is different than the first height of the bottom step 25a of the first frame 20. However, the bottom step 35a may be attached to the first frame 20 so that it is about 1-12 inches above the base of the ladder 10 so long the height of the two bottom steps 25a, 35a differ relative to the base of the ladder. Similar as discussed above, each additional step 35b-e may be attached to the second frame 30 at various heights in evenly spaced increments relative to the bottom step 35a.
As is more clearly shown in
Furthermore, performing work at an elevated work site from a position that is comfortable to the workman may improve safety as the workman may not have to stretch or crouch to perform a task. Stretching or crouching while working may make it more difficult for the workman to maintain his or her balance on a prior art double-sided step ladder and/or cause the workman to become fatigued quicker. This may be especially true if the workman must have to perform a task(s) at the elevated work site for an extended period of time.
It will be appreciated that the plurality of steps 25a-e attached to the first frame 20 may be substantially evenly spaced and/or the plurality of steps 35a-e may be substantially evenly spaced, however, such is not required by the principles of the present invention. A ladder 10 of the present invention may have unevenly spaced steps on one or both side that are configured to provide a plurality of good ergonomic conditions for working at a particular elevated site. For example, a particular elevated work site may cover a substantial area. Working in one section of the elevated work site may be more comfortable when standing on a step located on the first side of the ladder 10, while a task may be more comfortably performed in another section of the area from a different height. To access this other section the workman may only need to climb down the first side and ascend the opposite side. In contrast, if a telescopic or adjustable ladder was being used, the workman would have to adjust the ladder each time he or she needed to access different sections of the elevated work site. This may substantially slow down the progress of the work that needs to be performed and/or cause the workman to attempt tasks in different sections of the work site by dangerously stretching or crouching to reach a particular section of the worksite.
Also shown in
Turning now to
Referring now to
It will be appreciated that the plurality of steps 25a-e attached to the first frame 20 may be substantially evenly spaced and/or the plurality of steps 35a-e may be substantially evenly spaced. As explained above, however, an uneven staggering of steps 25a-e relative to steps 35a-e may be preferred in some circumstances.
There is thus disclosed an improved double-sided step ladder. It will be appreciated that numerous changes may be made to the present invention without departing from the scope of the claims.
| Number | Date | Country | |
|---|---|---|---|
| 61651055 | May 2012 | US |
