Patent Publication Number: US-9834988-B1

Title: Ladder platform attachment

Description:
RELATED APPLICATION 
     This application claims the benefit of and priority to U.S. provisional application No. 62/368,215, filed Jul. 29, 2016, titled “Ladder Platform Attachment,” the entirety of which application is incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to ladder platform attachments that increase a person&#39;s safety when the person works standing on a ladder. 
     BACKGROUND 
     When persons, particularly carpenters, painters, and persons of advanced age climb a ladder and install a ladder platform attachment thereon, an unsteady awkward physical stance may occur in the process. The risk of physical imbalance may also occur if both hands are concurrently required to adjust or shift the ladder platform from one rung level to another, thereby precluding gripping the ladder. 
     Prior art, such as U.S. Pat. No. 2,871,067 and U.S. Des. No. 248,777, force the user to repeatedly assume an unsteady physical stance when positioning the platform in order to stand on it; and later in order to descend, to remove the residual obstacle the platform has become. In each case the platform must be manipulated while the user is standing on a bent-knee leg on the next higher rung above the positioned platform and must stretch downward twelve inches to shift the platform by using one foot to do so. It is a risky task for an elderly person or one with knee problems! 
     The risk of physical imbalance may also occur if both hands are concurrently required to adjust elements of a ladder attachment, thereby precluding the availability of even one hand to grip the ladder to maintain physical balance. 
     Additionally, the pain produced in the arches of feet whenever a narrow ladder rung or the extent of the rear end of the platform fails to adequately support the heels of the feet may produce risk of distraction. 
     SUMMARY 
     All examples and features mentioned below, in the Summary, the Description, and the Claims, can be combined in any technically possible way. 
     In one aspect, a portable ladder platform attachment, for increasing a person&#39;s safety when standing on a ladder, comprises a platform having a surface, a forward edge, a rear edge, and opposing side edges, and a rod having a serpentine shape confined within a vertical plane above a centerline extending between the forward and rear edges of the platform. The rod has a first end coupled to the platform closer to the forward edge than to the rear edge, a midsection that extends above and substantially parallel to the surface of the platform along the centerline, and a second end shaped as a hook sized to fit closely about an upper rung of the ladder while the platform sits on a lower rung of the ladder. 
     In another aspect, a ladder platform attachment, for increasing a person&#39;s safety when standing on a ladder, comprises a platform having a surface, a forward edge, and a rearward edge, and a lone rod having a serpentine shape confined within a vertical plane above a centerline extending between the forward and rear edges of the platform. The rod has a first end coupled to the platform near the forward edge and a second end shaped as a hook sized to fit closely about a rung of the ladder. The rod having a vertical extent that is substantially equal to a vertical distance between an upper rung and an adjacent lower rung of the ladder. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and further advantages of this invention may be better understood by referring to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. In the following description, like reference characters designate like or corresponding parts or points throughout the views. 
         FIG. 1  is a perspective view of an embodiment of a ladder platform attachment in operative use upon the ladder. 
         FIG. 2  is a side view of the ladder platform attachment with a rod and a crossbar. 
         FIG. 3  is a view of the rod solidly attached to the crossbar. 
         FIG. 4  is a top view of the ladder platform attachment. 
         FIG. 5  is a perspective view of another embodiment of a ladder platform attachment. 
         FIG. 6  is a side of the ladder platform attachment of  FIG. 5 . 
         FIG. 7  is a perspective view of another embodiment of a ladder platform attachment. 
     
    
    
     DETAILED DESCRIPTION 
     Ladder platform attachments described herein may comprise a platform coupled to a crossbar that is solidly connected to one end of a rod, while the other end of the rod is shaped as a hook whereby the attachment may be hung on a rung of a ladder. The design of a ladder platform attachment is based on the perception that when a person stands on a platform, the feet are not positioned to rest in side by side contact, but instead rest a distance apart to maintain physical stability. This separation affords a structure, wherein a serpentine shaped rod element may be confined within a plane vertical above the centerline running the length of the platform, as the basis for a ladder platform structure that resolves the enumerated risks. 
     To accomplish the aforementioned advantages, the ladder platform attachment comprises a platform hinged to a crossbar that is joined to one end of a rod. The ends of the crossbar are inserted in opposing swivel ports in two parallel flanges attached to the platform. The rod&#39;s other end is shaped into a hook for hanging the ladder platform attachment on a ladder rung. In general, the shape of the hook complements the shape of the rungs of the particular commercial brand of ladder for which the ladder platform attachment is designed. The shape of the rod can be confined within a plane vertical above the centerline running a length of the platform, from front to rear. In one embodiment, the rod rises through an aperture in the forward end of the platform and then curves toward the rear end while parallel to the platform&#39;s upper surface, then curves sharply upward when past the overshadowing rung to hang thereon with its hook. 
     Thereby, when the ladder platform attachment is hung on the ladder, between two adjacent ladder rungs, the crossbar attached to the rod supports the forward end of the platform, and, in the process of its installation on the ladder, the platform lifts slightly as it slides over a rung, and then automatically, by it weight, shifts on the crossbar hinge, and thereby settles its rear end on the lower rung. The width of the ladder platform attachment depends upon the particular commercial brand of ladder for which the ladder platform attachment is designed. Simultaneously, the platform also protrudes sufficiently beyond the lower rung to support for the soles&#39; heels, without becoming an obstacle to ascending or descending the ladder, as occurs in the cited prior art. 
     The portion of the rod, just below the level of the upper rung that it hangs on, serves as a carrying handle to grip and carry the attachment with one hand, while the other hand is free to grip the ladder. 
     When a person transits the ladder, the rod with a hook at its end also serves as an extension for reaching up and hooking momentarily onto a ladder rung, thereby assuring two-handed control; concomitantly as one hand is free to shift its grip along the length of the ladder, the other hand gripping the rod alternatively shifts the rod&#39;s hook from rung to rung to hang thereon to maintain physical balance. 
     Advantages that the ladder platform attachment may provide include, but are not limited to: not imposing an unsteady physical stance of the user; providing a ladder platform attachment that is simple to attach to any section of the ladder, detachable, and easy to grip and safely shift from one height to another; leaving one hand of the user available to grip the ladder and maintain balance whenever the other hand must grip the ladder platform attachment to carry it; providing a ladder platform attachment that automatically settles on a rung for support at the moment it is installed on the ladder; providing a ladder platform attachment that is simple in design, inexpensive to manufacture and durable in construction. Other advantages include: having a platform sized to fit between the ladder side supports holding the ladder rungs; and having the position and size of the platform to fully support the soles of the feet. Embodiments of the ladder platform may include one or any combination of the following features: the platform, crossbar, and a rod may all be made of metal or plastic or a combination thereof; the platform may be coupled to one end of a rod by a hinge; the platform may be solidly joined to one end of the rod. 
       FIG. 1  shows a view of one embodiment of a ladder platform attachment  1  coupled to a ladder  10  (shown in phantom) with ladder rungs  20  that serve to support the attachment. The ladder platform attachment  1  includes a platform  30  with flanges  40  along the side edges of the platform, and, optionally, along all four side edges. The platform  30  has a rear end  50 , a front end  60 , and an aperture  70 . A rod  80  extends through the aperture  70 . A crossbar  90  projects through two opposing flanges  40  (only one end of the crossbar is shown). One end of the rod  80  is coupled to the crossbar  90  (obscured by the platform); the other end of the rod  80  has hook  100 . The hook  100  serves to hang the ladder platform attachment onto a ladder rung  20 . In general, the size and shape of the crook of the hook is designed to accommodate the particular size and shape of the ladder rung. A straight section  110  of the rod serves as a carrying handle to grip and carry the ladder platform attachment. The serpentine shape of the rod is confined within a vertical plane above a centerline  115  extending between the forward and rear edges of the platform. 
       FIG. 2  shows a side view of the ladder platform attachment  1 . The hook  100  of the ladder platform attachment is curled about one upper rung  20  of the ladder. The rear end  50  of the platform  30  sits on a second, adjacent lower rung  20 . The rod  80  has a hanger-like shape, having the straight section  110  that extends from the hook  100 , a first bend  120  into a second straight midsection  130  that runs above and generally parallel to the platform  30 , and a second bend  140  that extends the rod towards the platform  30 . The rod  80  is joined to the crossbar  90 , which projects through the sides of the flanges  40 . 
       FIG. 3  shows an end view of the ladder platform attachment  1  with the platform removed to show the rod  80  joined at one end to a mid-point (approximately) of the crossbar  90  and having the hook  100  at the opposite end. 
       FIG. 4  shows a top view of the platform  30 , side flanges  40 , shaft opening  70  in the platform, a portion of the rod  80 , the cross-bar  90 , which passes through an opening in the rod, and a ladder rung  20  near a rear edge  50  of the platform. While the vertical distance between sequential (i.e., adjacent, consecutive) rungs of a ladder is usually twelve inches, that distance may vary slightly depending on the angle of the ladder as it inclines against a supporting wall. To compensate for that slight variation, the hinge permits the platform  30  to settle in full contact onto the lower of two sequential ladder rungs, since the rod  80  may swivel in an arc. The ability of the rod to swivel can arise because the rod  80  is fused to a cross-bar  90  that can rotate freely within the side flanges  40 , or because the rod is not fixed to the cross-bar, which may or may not be fused to the side flanges, and can thus rotate freely about the cross-bar. That arc of free movement of the rod  80  is only limited at its extreme points by the rear edge  150  and forward edge  160  of the platform&#39;s shaft opening  70  through which the rod protrudes. Thereby the hinge provides a portion of the platform freedom of movement to, by its own weight, settle its rear end  50  via its side flanges  40  onto a ladder rung  20  for support. The cross-bar  90  holds up the front end  60  of the platform. Stainless steel side-mount rings  165  snap into respective grooves (not shown) on the shaft of the cross-bar  90  to secure the cross-bar  90  in its position. Washers (not shown) may be disposed between the flanges  40  and each side-mount ring  165 . 
       FIG. 5  shows another embodiment of a ladder platform attachment  1 , wherein the rod  80  has the hook  100 , a straight section  110 , first bend  120 , second straight section  130 , a second bend  140 , and a second straight section  170 , like the rod shown in  FIGS. 1-3 . The second straight section  177  extends past the front edge  60  of the platform  30 . The rod  80  further includes a third bend  180  that turns into a third straight section  190  that runs along the underside of the platform  30 . 
       FIG. 6  shows a side view of the embodiment of the ladder platform attachment  1  of  FIG. 5 , with the rod  80  connected (e.g., fused, welded) to the underside of the platform  30 . 
       FIG. 7  shows another embodiment of a ladder platform attachment  1 , with the rod  80  connected to the top surface  190  of the platform  30 , for example, by welding or by a hinge. The serpentine shape of the rod  80  is confined within a vertical plane above a centerline  200  extending between the forward and rear edges of the platform. 
     It is to be understood that terms such as “forward,” “back,” “rear,” “vertical,” “top”, “bottom”, “above,” “beneath,” “below,” and the like are terms to facilitate the description and are not to be construed as limitations of the aforementioned principles. Further, while these principles have been described in conjunction with a number of embodiments, it is evident that many alternatives, modifications, and variations would be or are apparent to those of ordinary skill in the applicable arts. References to “one embodiment” or “an embodiment” or “another embodiment” means that a particular, feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment described herein. A reference to a particular embodiment within the specification do not necessarily all refer to the same embodiment. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Accordingly, it is intended to embrace all such alternatives, modifications, equivalents, and variations that are within the spirit and scope of the principles described herein.