Patent Publication Number: US-10759641-B1

Title: Protective lift pad for materials handling vehicle

Description:
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     This application relates broadly and generally to a protective lift pad; and in exemplary embodiments described further herein, to a protective “bumper” pad designed for engaging and protecting materials carried by a materials handling vehicle, such as those utilizing a mechanical forklift. The exemplary pad is designed to protect materials from damage resulting from impact against the fork backrest. In many cases, even slight to moderate damage to fragile edges during handling can render the entire product unfit for commercial sale. 
     Forklift damage to materials in industrial warehouses and home improvement stores is substantial—estimated to be in the millions of dollars each year. In most home improvement stores, forklift operators have relatively little experience or formal training in the operation and maneuvering of lift trucks. When approaching a loaded pallet for transport, an operator will typically move the truck forward until the forks have clearly and firmly impacted the materials. While this ensures full extension of the fork tines into the pallet, the impact often damages the materials. Inherence sight limitations of the operator related to his physical position during operation of the forklift further contribute to the problem. 
     One prior art solution to this problem is to locate an impact sensor on the forkback of the lift truck. If the fork is bumped beyond the selected impact level, the sensor sounds an internal audible alarm. The sensor is intended to limit careless operation of the lift truck and create a safer, more efficient and productive work environment. A significant disadvantage of this attempted solution is that after the impact is made and the alarm sounds the materials damage has already occurred. Another solution is to provide better training and orientation programs for the vehicle operators. However, even for those most qualified operators, unavoidable circumstances and accidents will nevertheless occur in a certain percentage of runs. 
     SUMMARY OF EXEMPLARY EMBODIMENTS 
     Various exemplary embodiments of the present disclosure are described below. Use of the term “exemplary” means illustrative or by way of example only, and any reference herein to “the invention” is not intended to restrict or limit the invention to exact features or steps of any one or more of the exemplary embodiments disclosed in the present specification. References to “exemplary embodiment,” “one embodiment,” “an embodiment,” “various embodiments,” and the like, may indicate that the embodiment(s) of the invention so described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one embodiment,” or “in an exemplary embodiment,” do not necessarily refer to the same embodiment, although they may. 
     It is also noted that terms like “preferably”, “commonly”, and “typically” are not utilized herein to limit the scope of the claimed invention or to imply that certain features are critical, essential, or even important to the structure or function of the claimed invention. Rather, these terms are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the present invention. 
     According to one exemplary embodiment, the present disclosure comprises a materials handling vehicle with a mechanical lift including a horizontal extension and a vertical back. A protective lift pad is located on the mechanical lift, and is adapted for engaging and protecting materials carried by the vehicle. The protective lift pad comprises a flexible polymeric (or other cushioning) body having opposing first and second end edges defining therebetween a length of the body, and opposing first and second side edges defining therebetween a width of the body. A plurality of magnets are embedded within the flexible body, and are adapted for releasably magnetically mounting the protective lift pad to a metal surface on the vertical back of the mechanical lift. First and second opposing end flanges extend planarly outwardly from respective first and second end edges of the flexible body. A raised front engagement panel is located between opposing end flanges, and is spaced apart from opposing side edges of the flexible body. At least one vertical alignment tab is located along one of the first and second side edges of the flexible body. The alignment tab extends perpendicularly rearward from the body to reside adjacent an edge of the vertical back of the mechanical lift. The term “perpendicularly rearward” means extending in a rearward direction generally 90 degrees to a major planar surface of the flexible body. 
     According to another exemplary embodiment, the flexible body comprises an injection molded homogenous construction. 
     According to another exemplary embodiment, a perimeter margin is formed around the front engagement panel. 
     According to another exemplary embodiment, the perimeter margin has a uniform dimension of less than 1.0 inch. 
     According to another exemplary embodiment, each end flange extends planarly outward from the flexible body a distance substantially equal to the dimension of the perimeter margin. As used herein, the term “planarly outward” means extending in a direction co-planar with a major planar surface of the flexible body, or within a plane substantially parallel to a major planar surface of the flexible body. 
     According to another exemplary embodiment, the alignment tab is formed substantially flush to the side edge of the flexible body. 
     According to another exemplary embodiment, the alignment tab extends perpendicularly rearward from the flexible body a distance less than 1.0 inch. 
     According to another exemplary embodiment, a plurality of integrally-molded magnet sockets are formed with an underside of the flexible body. 
     According to another exemplary embodiment, each of the magnets is carried in an annular metal housing. 
     According to another exemplary embodiment, an embedment disk is spaced apart from and connected to the magnet housing, and is integrally molded within the flexible body to permanently affix the magnets/magnet housings to the protective pad. 
     According to another exemplary embodiment, the mechanic lift comprises a pair of laterally spaced forks. Each fork comprises a vertical metal backrest, an elbow, and an elongated horizontal tine. The lift pad is releasably magnetically mounted to the vertical metal backrest of the fork. 
     According to another exemplary embodiment, the width of the flexible body is substantially equal to a width of the vertical backrest of the fork. 
     According to another exemplary embodiment, the lift pad extends vertically upward from the elbow of the fork. 
     According to another exemplary embodiment, a grid structure is integrally molded with an underside of the flexible body. 
     According to another exemplary embodiment, the length of the flexible body is greater than 4 times the width of the flexible body. 
     In another exemplary embodiment, the present disclosure comprises a protective lift pad designed for engaging and protecting materials carried by a materials handling vehicle using a mechanical lift. 
     In yet another exemplary embodiment, the present disclosure comprises a method for minimizing damage to materials carried on a mechanical lift of a materials handling vehicle. The mechanical lift includes a horizontal extension and a vertical back. The method includes the step of locating a protective lift pad adjacent the vertical back. 
     In one or more exemplary embodiments, it is an object of the disclosure to provide a protective lift pad adapted for engaging and protecting materials carried by a materials handling vehicle, thereby reducing materials damage and costs. 
     In one or more exemplary embodiments, it is another object of the disclosure to provide a protective lift pad which does not interfere with the operator&#39;s line of sight. 
     In one or more exemplary embodiments, it is another object of the disclosure to provide protective lift pad which does not interfere with fork adjustment. 
     In one or more exemplary embodiments, it is another object of the disclosure to provide protective lift pad which is readily removable, exchangeable and replaceable. 
     In one or more exemplary embodiments, it is another object of the disclosure to provide a method for protecting materials, such as wallboard, sheet rock, sheet metals, tile board, paneling, foam products, finished woods, acoustical materials, glass, can goods, food products, packaged, unpackaged, and in-process manufactured materials, medical materials and packaging, finished and unfinished goods, and other fragile items commonly carried on mechanical lifts. 
     In one or more exemplary embodiments, it is another object of the disclosure to provide a materials handling vehicle which incorporates a protective lift pad designed for engaging and protecting materials carried by the vehicle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein: 
         FIG. 1  is a perspective view of materials handing vehicle incorporating a pair of protective lift pads according to one exemplary embodiment of the present disclosure; 
         FIG. 2  is a further perspective view of the exemplary materials handing vehicle, and showing the present lift pad and mounting magnets exploded away from the vehicle fork; 
         FIG. 3  is an underside perspective view of the exemplary protective lift pad, and showing the mounting magnets exploded away from the flexible body; 
         FIG. 4  is a further underside perspective of the exemplary protective lift pad with the mounting magnets embedded in respective sockets formed with the flexible body; 
         FIG. 5  is a cross-sectional view taken substantially along line  5 - 5  of  FIG. 4 ; 
         FIG. 6  is a further cross-sectional view taken substantially along line  6 - 6  of  FIG. 4 ; 
         FIG. 7  demonstrates one exemplary technique for applying the present lift pad to the metal backrest of the vehicle fork; 
         FIG. 8  demonstrates one exemplary technique for removing the present lift pad from the metal backrest of the vehicle fork; and 
         FIG. 9  shows the exemplary lift pad mounted on the vehicle fork and in an exemplary position designed to engage and protect materials carried by the vehicle. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS AND BEST MODE 
     The present invention is described more fully hereinafter with reference to the accompanying drawings, in which one or more exemplary embodiments of the invention are shown. Like numbers used herein refer to like elements throughout. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be operative, enabling, and complete. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof. Moreover, many embodiments, such as adaptations, variations, modifications, and equivalent arrangements, will be implicitly disclosed by the embodiments described herein and fall within the scope of the present invention. 
     Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Unless otherwise expressly defined herein, such terms are intended to be given their broad ordinary and customary meaning not inconsistent with that applicable in the relevant industry and without restriction to any specific embodiment hereinafter described. As used herein, the article “a” is intended to include one or more items. Where only one item is intended, the term “one”, “single”, or similar language is used. When used herein to join a list of items, the term “or” denotes at least one of the items, but does not exclude a plurality of items of the list. 
     For exemplary methods or processes of the invention, the sequence and/or arrangement of steps described herein are illustrative and not restrictive. Accordingly, it should be understood that, although steps of various processes or methods may be shown and described as being in a sequence or temporal arrangement, the steps of any such processes or methods are not limited to being carried out in any particular sequence or arrangement, absent an indication otherwise. Indeed, the steps in such processes or methods generally may be carried out in various different sequences and arrangements while still falling within the scope of the present invention. 
     Additionally, any references to advantages, benefits, unexpected results, or operability of the present invention are not intended as an affirmation that the invention has been previously reduced to practice or that any testing has been performed. Likewise, unless stated otherwise, use of verbs in the past tense (present perfect or preterit) is not intended to indicate or imply that the invention has been previously reduced to practice or that any testing has been performed. 
     Referring now specifically to the drawings,  FIGS. 1 and 2  illustrate a materials handling vehicle  10  including one or more protective lift pads  20  according to exemplary embodiments of the present disclosure. The exemplary vehicle  10  incorporates a conventional mechanical lift  11  with spaced vertical masts  12 ,  14 , a carriage  15  designed for upward and downward movement along the masts  12 ,  14 , and a pair of forks  16 . Each fork  16  has an integrally-formed vertical metal backrest  17 , a transition elbow  18 , and an elongated horizontal tine  19 . The backrest  17  may be permanently affixed to the carriage  15 , and has a thickness which protrudes slightly forward of the carriage front  15 A. The forks  16  are especially applicable for collecting building materials, such as sheet rock and wallboard, stacked in a unit load on a wood pallet or other standard carrier. In existing prior art vehicles, the protruding thickness of the vertical backrest is a common source of damage to materials during loading and transport—particularly materials with relatively fragile edges, such as sheet rock and wallboard. 
     To address this issue, the protective lift pads  20  of the present disclosure releasably magnetically mount to the vertical backrest  17  of one or both metal forks  16 , as described further below. When positioned as shown in  FIG. 9 , the exemplary lift pad(s)  20  engage and cushion materials “M” carried by the vehicle forks  16  on wood pallet “P”. 
     Referring to  FIGS. 2, 3, and 4 , the exemplary lift pad  20  comprises a flexible polymeric body  21  having opposing first and second end edges  23 ,  24 , and opposing first and second side edges  25 ,  26 . The distance between end edges  23 ,  24  defines a length of the flexible body  21 , while the distance between side edges  25 ,  26  defines a width of the flexible body  21 . The length of the flexible body  21  may be more than 3-4 times its width. In one embodiment, for example, the length is about 20 inches and the width is about 5 inches. For larger size forks, the body dimension may be about 36 inches in length by 8 inches wide, or greater. 
     As best shown in  FIGS. 3 and 5 , first and second opposing end flanges  31 ,  32  are integrally formed with and extend planarly outwardly from respective first and second end edges  23 ,  24  of the flexible body  21 . The end flanges  31 ,  32  form respective handles for applying and removing the lift pad  20 , and provide increased protective coverage along the vertical backrest  17  of the fork  16 . A raised front engagement panel  34  ( FIGS. 1 and 2 ) is located between opposing end flanges  31 ,  32 , and is spaced apart from opposing side edges  25 ,  26  of the flexible body  21 . In the exemplary embodiment, the front engagement panel  34  is about 0.25 inches thick and is substantially rectangular with a uniform perimeter margin  35  formed around all four sides. The perimeter margin  35  frames the engagement panel  34  in a front center of the lift pad  20 , and may be between about 0.5 and 1.0 inch wide around all sides of the panel  34 . As such, each end flange  31 ,  32  may extend planarly outward from the flexible body  21  a distance corresponding to the uniform width of the perimeter margin  35 . 
     Vertical alignment tabs  38  are located along one or both side edges  25 ,  26  of the flexible body  21  and extend perpendicularly rearward towards the vehicle  10  to reside adjacent an edge of the fork&#39;s vertical backrest  17 , as best show in  FIGS. 1 and 2 . The exemplary alignment tabs  38  are formed substantially flush (or even) with side edges  25 ,  26  of the flexible body  21 , and may be selectively cut and removed along one side edge to allow the lift pad  20  to fit larger size forks  16 . The alignment tabs  38  facilitate proper placement of the lift pad  20  on the vehicle fork  16 , and are sufficiently long (e.g., between about 0.5 and 1.0 inch) to restrict inadvertent lateral shifting of the pad  20  during use. In one embodiment, the width of the flexible body  21  is substantially equal to the width of the vertical backrest  17  of the vehicle fork  16 . 
     Referring to  FIGS. 3-6 , a number of magnets  40  (e.g., permanent magnets) function to releasably magnetically mount the protective lift pad  20  to a metal surface on the fork backrest  17 . Each magnet  40  is carried in an annular metal housing  41 . The magnet housing  41  is connected by reduced diameter metal neck  42  to a metal embedment disk  44 —all of which are contained within a molded socket  45  formed with an underside of the flexible body  21 . The flexible body  21  may further comprise an integrally-molded underside grid structure  48  designed to promote increased flexibility and strength, and to reduce the overall weight of the lift pad  20 . During manufacture, each magnet assembly (including magnet  40 , housing  41 , neck  42 , and embedment disk  44 ) is first placed in a mold, and a liquid polymer material then injected such that the magnet assembly becomes integrally and permanently embedded within the homogenous material of the flexible body  21 . See  FIGS. 4, 5 and 6 . After the injection-molding process, the magnet and magnet housing may remain partially or entirely exposed, as shown in  FIG. 4 . 
       FIGS. 7 and 8  demonstrate installation and removal of the protective lift pad  20  onto and from the materials handing vehicle  10 . As shown in  FIG. 7 , the exemplary lift pad  20  may be installed by first locating the alignment tabs  38  against the vertical edge of the fork&#39;s backrest  17 , such that the flexible body  21  is angled outwardly from the metal surface  17 A to prevent the mounting magnets  40  from engaging. The angled lift pad  20  can then be shifted upward or downward for proper vertical alignment on the metal backrest  17 . Once aligned, the flexible body  21  is pivoted inwardly towards the backrest  17  so that the magnets  40  attract and firmly engage the metal surface  17 A, thereby releasably locking the protective lift pad  20  in a fixed position. In one exemplary application, the protective lift pad  20  is intended to mount to the metal backrest  17  of the fork  16  just above the horizontal tine  19  and directly adjacent the transition elbow  18 . See  FIG. 9 . Additionally, the “stepped” profile of the lift pad  20  at its bottom end may enable increased protective coverage at the transition elbow  18 . 
       FIG. 8  illustrates an exemplary technique for removing the protective lift pad  20  from the vehicle fork  16 . Grasping the top and bottom end flanges  31 ,  32 , the user can pull and separate the mounting magnets  40  from the metal surface  17 A of the fork  16 , thereby quickly and easily releasing the lift pad  20  from the vehicle  10 . 
     In alternative exemplary embodiments, the protective lift pad  20  may be fabricated of an assembly of individual components, may comprise materials other than polymer, and may be rigid or semi-rigid. The protective lift pad  20  may also be fabricated in any desired shape and dimension. Additionally, one or multiple magnets may be utilized and arranged in any suitable manner to releasably magnetically mount the lift pad to the vehicle fork. 
     An exemplary embodiment of the protective lift pad is illustrated in the attached drawings and photographs. As best shown in the drawing sheet, to enable convenient exchange and replacement, the protective lift pad is preferably removably attached to the fork backrest using a number of magnets. The drawing sheet further details exemplary dimensions of the present lift pad. 
     For the purposes of describing and defining the present invention it is noted that the use of relative terms, such as “substantially”, “generally”, “approximately”, and the like, are utilized herein to represent an inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. 
     Exemplary embodiments of the present invention are described above. No element, act, or instruction used in this description should be construed as important, necessary, critical, or essential to the invention unless explicitly described as such. Although only a few of the exemplary embodiments have been described in detail herein, those skilled in the art will readily appreciate that many modifications are possible in these exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the appended claims. 
     In the claims, any means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. Unless the exact language “means for” (performing a particular function or step) is recited in the claims, a construction under 35 U.S.C. § 112(f) [or 6th paragraph/pre-AIA] is not intended. Additionally, it is not intended that the scope of patent protection afforded the present invention be defined by reading into any claim a limitation found herein that does not explicitly appear in the claim itself.