Patent Publication Number: US-2019178344-A1

Title: Directional Link Chain for Use in Chain Wheel Operators

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Design patent application Ser. No. 29/628,950, filed on Dec. 8, 2017 entitled “DIRECTIONAL LINK CHAIN”, the disclosure of which is hereby incorporated in its entirety at least by reference. 
     FIELD 
     The present disclosure generally relates to link chain; and, is more particularly directed to directional link chain for use in chain wheel operators. 
     BACKGROUND 
     Through applied effort, ingenuity, and innovation, Applicant has identified a number of deficiencies and problems with link chain used on chain wheel operators, such as chain falls, roll-up doors, valve operators. In an example application, a chain fall, also called a chain hoist or differential pulley, is used to manually lift heavy objects by using the mechanical advantage of a gear system. When lifting heavy objects, a high amount of force is applied to a chain fall&#39;s lifting chains, which have limited tensile strength depending on the chain grade used. While operating a chain fall, an operator pulls a hand chain comprised of interconnected link chain to move the gear system, which in turn rotates the lifting chains to move a heavy object or attached load vertically or horizontally. Depending on the specific gearing of the chain fall used, it requires a tremendous amount of time to move a very heavy object a small distance. Occasionally, an operator may be pulling the hand chain in the wrong direction resulting in the load moving in the wrong direction. This could result at the very least in time consuming delays, and in some situations cause the load to be imbalanced and not level when multiple operators are used. This can be a serious problem and can create a significant safety hazard depending on the application and object lifted. Consequently, Applicant has developed a solution that is embodied by the present invention, which is described in detail below. 
     SUMMARY 
     The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later. 
     An object of the present disclosure is a directional link chain for use in chain wheel operators, such as chain falls and roll up door systems, comprising a series of interconnected directional links, each directional link comprising a first U-shaped end and a second U-shaped end forming an integral link chain, wherein the first and second U-shaped ends are opposed at a transverse plane and symmetric to a longitudinal axis; and, a directional indication element consisting of a pair of directional members, wherein each directional member of the pair of directional members includes a proximal end and a distal end, the distal ends forming at least one indication point, the directional indication element corresponding to a directionality of travel of a load during operation in a chain wheel operator. 
     Another object of the present disclosure is a directional link chain for use in chain wheel operators or roll-up garage door systems comprising a series of interconnected directional links, each directional link comprising at least one U-shaped end; and, a directional indication element having at least one indication point, the directional indication element corresponding to a directionality of travel of a load during operation in a chain wheel operator. 
     The foregoing has outlined rather broadly the more pertinent and important features of the present invention so that the detailed description of the invention that follows may be better understood and so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the disclosed specific structures may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should be realized by those skilled in the art that such equivalent structures do not depart from the spirit and scope of the invention as set forth in the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and other objects, features and advantages of the present disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is an illustration of link chain of the prior art for use in a chain fall, according to an embodiment; 
         FIG. 2 a    is an isometric view of a directional link chain, according to an embodiment; 
         FIG. 2 b    is a front view of  FIG. 2   a;    
         FIG. 3 a    is a front view of a directional link chain, according to an embodiment; 
         FIG. 3 b    is a front view of a directional link chain having an alternative directional indication member, according to an embodiment; 
         FIG. 3 c    is a front view of an alternative directional link chain, according to an embodiment; 
         FIG. 3 d    is a front view of an alternative directional link chain, according to an embodiment; 
         FIG. 4  is an illustration of a series of interconnected directional links for use in a vertical chain fall, according to an embodiment; 
         FIG. 5 a    is an illustration of a series of interconnected directional links for use in a horizontal chain fall, according to an embodiment; and, 
         FIG. 5 b    is a front view of a directional link chain of the series of interconnected directional links of  FIG. 5   a.    
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments are described herein to provide a detailed description of the present disclosure. Variations of these embodiments will be apparent to those of skill in the art. Moreover, certain terminology is used in the following description for convenience only and is not limiting. For example, the words “right,” “left,” “top,” “bottom,” “upper,” “lower,” “inner,” “outer,” “proximal,” “distal,” “transverse,” and “longitudinal” designate directions in the drawings to which reference is made. In addition, reference to “first,” “second,” “third,” and etc. members throughout the disclosure (and in particular, claims) are not used to show a serial or numerical limitation but instead are used to distinguish or identify the various members of the group. The word “a” is defined to mean “at least one.” The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import. 
     Referring now to  FIG. 1 , link chain  100  of the prior art for use in a chain fall or roll-up door  101  is illustrated. During operation, a user or multiple users pull link chain  100  connected to a gear system in chain fall or roll-up garage door  101  enabling lifting chain  102  and attached load via hook  103  to be moved vertically or horizontally. This is especially useful when heavy loads are required to be moved, as the mechanical advantage of the gear system allows the user or multiple users to exert less force necessary to move the heavy loads when compared to other methods. However, link chain  100  of the prior art lacks any indication of direction corresponding to the direction of the gear system and corresponding load direction. This can disadvantageously lead to users pulling the link chain, and the corresponding load, in the opposite direction as intended. 
     Referring now to  FIGS. 2 a -2 b   , a directional link chain  200  is illustrated. According to an embodiment, directional link chain  200  comprises a first U-shaped end  201  and a second U-shaped end  202  opposed at a transverse plane  203 , such that the first U-shaped end is above the transverse plane, and the second U-shaped end is below the plane. First U-shaped end  201  and second U-shaped end  202  form an integral link chain configured to be interconnected to a series of interconnected directional links  400  ( FIG. 4 ). In an embodiment, first U-shaped end  201  and second U-shaped end  202  are symmetric to a longitudinal axis  204 . 
     In an embodiment, a directional indication element  205  is provided, the directional indication element consisting of a pair of directional members  206 / 207  each directional member having a proximal end  208 / 209  and a distal end  210 / 211 . In an embodiment, the proximal end of each directional member is attached to an interior surface  212  of the integral link chain. The distal ends of each directional member are combined to form an upper indication point  213  and a lower indication point  214 . The directional indication element indicates to an operator the direction of load travel for use in chain falls or similar chain driven hand crank systems. This will be discussed in further detail below. 
     In an embodiment, upper indication point  213  and lower indication point  214  are positioned along longitudinal axis  204 . The pair of directional members is positioned symmetrically in relation to longitudinal axis  204 , such that the pair of directional members forms a pair of equal acute angles α from longitudinal axis  204 . Angles α define the slope of the pair of directional members of directional indication element  205 . Specifically, the pair of equal acute angles α corresponds to the slope of the pair of directional members defining a V-shape of directional indication element  205 . The V-shape of directional indication element  205  is recognized as an arrow, and advantageously used to show load directional travel during operation. It should be understood, that angles α may vary depending on design considerations for the directional indication element. For instance, the V-shape or arrow is easily recognizable by a user during operation, however by varying angles α, the directional indication element may cause some confusion, especially if angles α are too large, i.e. close to 90 degrees. Thus, it is critical to select angles α that avoid confusion and clearly indicate a direction via directional indication element  205 , while factoring in material usage, construction, weight, and balance of the directional indication element and the direction link chain as a whole. Preferably, each angle α of the pair of equal acute angles is approximately 45 degrees. 
     Preferably, upper indication point  213  is positioned approximate to transverse plane  203 . This ensures proper weight and balance of the directional indication element when factoring in the pair of equal acute angles α of directional members  206  and  207 . 
       FIGS. 3 a -3 d    are front views of various embodiments of a directional link chain. Referring now to  FIG. 3 a   , an embodiment of a directional link chain  301  is illustrated. Directional link chain  301  comprises a directional indication element  302  having a similar structure as described above, and illustrated in  FIGS. 2 a   - 2   b.    
     Referring now to  FIG. 3 b   , an embodiment of a directional link chain  303  is illustrated. Directional link chain  303  comprises a directional indication element  304 . Directional indication element  304  consists of a square shape material having a negative indication space  305  configured to indicate the direction of travel of directional link chain  303  during operation in a chain fall, chain hoist, roll-up garage door, chain trolley hoist, or other hand crank chain system. 
     Referring now to  FIG. 3 c   , an embodiment of a directional link chain  306  is illustrated. Directional link chain  306  comprises a first U-shaped end  307 , a second U-shaped end  308 , and directional indication element  309  positioned adjacent to a bottom portion  310  of second U-shaped end  308 . 
     Referring now to  FIG. 3 d   , an embodiment of a directional link chain  311  is illustrated. Directional link chain  311  comprises a U-shaped end  312  and directional indication element  313  positioned adjacent to a bottom portion  314  of U-shaped end  312 . 
     Referring now to  FIG. 4 , a series of interconnected directional links  400  for use in a vertical chain fall or roll-up garage door  403  is illustrated. According to an embodiment, each directional link chain  401  of the series of interconnected directional links comprises a directional indication element  402  having a vertical indication corresponding to a directionality of load travel during operation in vertical chain fall  403 . Specifically, during operation, a user or multiple users pull the series of interconnected directional links connected to a gear system in vertical chain fall  403  enabling lifting chain  404  and an attached load via hook  405  to be moved vertically, i.e. up or down. The directional indication elements of each directional link chain of the series of interconnected directional links enable the user or multiple users to visually recognize the gear system direction, and corresponding load direction via the up or down indication displayed via each directional indication element to efficiently move the load the desired direction without trial and error. For instance, if a user desires to move the attached load in a vertically downward direction, the user would pull on the series of interconnected directional links having directional indication elements indicating a downward direction. Alternatively, if a user desires to move the attached load in a vertically upward direction, the user would pull on the series of interconnected directional links having directional indication elements indicating an upward direction. Directional link chain  401  may be any directional link chain described above and illustrated in  FIGS. 2 a   - 3   d.    
     Referring now to  FIG. 5 a   , a series of interconnected directional links  500  for use in a horizontal chain fall or roll-up garage door  503  is illustrated. According to an embodiment, each directional link chain  501  of the series of interconnected directional links comprises a directional indication element  502  having a horizontal indication corresponding to a directionality of travel during operation in horizontal chain fall  503 . In the exemplary embodiment illustrated, horizontal chain fall  503  is a trolley hoist. During operation, a user or multiple users pull the series of interconnected directional links connected to a gear system in horizontal chain fall  503  enabling trolley  516  (with or without an attached load) to be moved horizontally, i.e. left or right. For the purpose of this disclosure, trolley  516  can be referred to as a load. 
     The directional indication elements of each directional link chain of the series of interconnected directional links enable the user or multiple users to visually recognize the gear system direction, and corresponding trolley direction via the left or right indication displayed via each directional indication element to efficiently move the trolley the desired direction without trial and error. For instance, if a user desires to move the trolley in a horizontally leftward direction, the user would pull on the series of interconnected directional links having directional indication elements indicating a leftward direction. Alternatively, if a user desires to move the trolley in a horizontally rightward direction, the user would pull on the series of interconnected directional links having directional indication elements indicating a rightward direction. 
     Referring now to  FIG. 5 b   , directional link chain  501  is illustrated. According to an embodiment, directional link chain  501  comprises a first U-shaped end  503  and a second U-shaped end  504  opposed at a transverse plane  505 , such that the first U-shaped end is above the transverse plane, and the second U-shaped end is below the plane. First U-shaped end  503  and second U-shaped end  504  form an integral link chain configured to be interconnected to a series of interconnected directional links  500  ( FIG. 5 a   ). In an embodiment, first U-shaped end  503  and second U-shaped end  504  are symmetric to a longitudinal axis  506 . 
     As previously described, directional link chain  501  comprises a directional indication element  502 , the directional indication element consisting of a pair of directional members  507 / 508 , each directional member having a proximal end  509 / 510  and a distal end  511 / 512 . In an embodiment, the proximal end of each directional member is attached to an interior surface  513  of the integral link chain. The distal ends of each directional member are combined to form a left indication point  514  and a right indication point  515 , such that a horizontal plane intersecting the left indication point and the right indication point is parallel to transverse plane  505 . 
     The present disclosure includes that contained in the appended claims as well as that of the foregoing description. Although this invention has been described in its exemplary forms with a certain degree of particularity, it is understood that the present disclosure of has been made only by way of example and numerous changes in the details of construction and combination and arrangement of parts may be employed without departing from the spirit and scope of the invention.