Abstract:
Implementations described herein relate to guide assemblies for a tire lift assembly. The guide assembly includes a mounting plate, a support structure extending from the mounting plate, and rollers. The mounting plate includes mounting holes to connect the mounting plate to a casting of the tire lift assembly. The support structure includes a first wall, a second wall, and a third wall that define an opening. The first wall is connected to and extending from the mounting plate, and the second wall and the third wall are connected to and extending from the first wall. The second wall may be opposite the third wall. The rollers are rotatably supported by the second wall and the third wall with each roller positioned on opposing sides of the opening. Each roller rotates relative to the support structure when a cable of the tire lift assembly travelling through the opening contacts the roller.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
       [0001]    The present application claims the benefit of U.S. Provisional Patent Application No. 62/139,222, filed Mar. 27, 2015, and entitled “TIRE LIFT CABLE GUIDE ASSEMBLY”, the entirety of which is incorporated herein. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    The present disclosure relates to tire lifts and, more particularly, to tire lifts for use in tire retreading operations. 
       BACKGROUND 
       [0003]    Various types and arrangements for tire lifts are known. Certain specialized applications, such as tire retread operations, use specialized lifts that are used to move tires and tire carcasses along an assembly line, and to also help mount and dismount those tires from various machines and equipment disposed along the assembly line. Cables having hooks connected at their ends are sometimes used to engage tires or carcasses by their beads so they can be lifted and transported to and from tire equipment. The sometimes unique sequences of motion used in retreading operations, which include lifting or lowering the tire while simultaneously laterally moving the tire in one or two directions, place unusual strain patterns on the lifting equipment. In one exemplary condition, a cable used to lift and lower a tire may be subjected to lateral or swinging loading while lifting or lowering the tire, which may interfere and wear areas of the lift surrounding the cable, thus necessitating service, repair or replacement of various structures of the lift. 
       SUMMARY 
       [0004]    The disclosure provides a guide system for a cable in a compound motion tire lift, which guide system protects a casting of the lift from undue wear from contact with a lift cable. In one embodiment, the casting forms a radius for guiding the cable as the cable lifts and lowers the tire, as well as swings or angularly displaces relative to an opening or passage formed in the casting. Over time, the cable may wear the area of the casting surrounding the opening through which the cable extends, causing the casting to be replaced. Additionally, by rubbing against the casing, the cable becomes frayed, also needing replacement. The disclosure provides a guide that provides rolling surfaces that protect the casting and cable from damage. These rolling surfaces protect against swinging angles of the cable along any direction, and thus are arranged along four separate axes around the cable. In one embodiment, the cable guide can be offered as original equipment with a tire lift, and may additionally be configured as a retrofit or additional kit on existing lifts. The cable guide is uniquely suited for tire lift applications in which the hoisting or lifting of tires or carcasses imparts appreciable lateral or swinging loads on the cable while the cable is moving to raise or lower the tire. 
         [0005]    One implementation relates to a guide assembly for a tire lift assembly that includes a mounting plate, a support structure extending from the mounting plate, and a first pair of rollers. The mounting plate has mounting holes to connect the mounting plate to a casting of the tire lift assembly. The support structure includes a first wall, a second wall, and a third wall defining an opening. The first wall is connected to and extends from the mounting plate. The second wall and the third wall are connected to and extend from the first wall. The second wall is opposite the third wall. The first pair of rollers are rotatably supported by the second wall and the third wall. The first pair of rollers are positioned on opposing sides of the opening defined by the first wall, the second wall, and the third wall. Each roller of the first pair of rollers rotates relative to the support structure when a cable of the tire lift assembly travelling through the opening contacts a roller of the first pair of rollers. 
         [0006]    In some implementations, the guide assembly further includes a second pair of rollers rotatably supported by the first wall. The second pair of rollers are positioned non-parallel to the first pair of rollers on opposing sides of the opening defined by the first wall, the second wall, and the third wall. In some implementations, the first pair of rollers are perpendicular to the second pair of rollers. In some implementations, the first pair of rollers and the second pair of rollers surround the opening. In some implementations, the support structure further includes a fourth wall opposite the first wall. The fourth wall is connected to and extends from the second and third wall. The second pair of rollers are further rotatably supported by the fourth wall. In some implementations, the first pair of rollers are rotatably supported by fasteners extending through a set of holes formed in the second wall. In some implementations, the first pair of rollers are bushings. In some implementations, the support structure is U-shaped. 
         [0007]    Another implementation relates to a tire lift assembly that includes a cable dispensing portion, a cable anchor portion, an expandable portion, a cable, and a guide assembly. The cable dispensing portion includes a casting forming an integral passage. The cable anchor portion is opposite the cable dispensing portion. The expandable portion is positioned between the cable anchor portion and the cable dispensing portion. The cable is anchored at the cable anchor portion and extends through the expandable portion and out through the integral passage of the casting of the cable dispensing portion. The guide assembly is connected to the casting of the cable dispensing portion and includes a mounting plate, a support structure extending from the mounting plate, and a first pair of rollers. The mounting plate is connected to the casting of the cable dispensing portion. The support structure includes a first wall, a second wall, and a third wall defining an opening. The first wall is connected to and extends from the mounting plate. The second wall and the third wall are connected to and extend from the first wall. The second wall is opposite the third wall. The first pair of rollers are rotatably supported by the second wall and the third wall. The first pair of rollers are positioned on opposing sides of the opening defined by the first wall, the second wall, and the third wall. Each roller of the first pair of rollers rotates relative to the support structure when the cable contacts a roller of the first pair of rollers. 
         [0008]    In some implementations, the guide assembly further includes a second pair of rollers rotatably supported by the first wall. The second pair of rollers are positioned non-parallel to the first pair of rollers on opposing sides of the opening defined by the first wall, the second wall, and the third wall. In some implementations, the first pair of rollers are perpendicular to the second pair of rollers. In some implementations, the support structure further includes a fourth wall opposite the first wall. The fourth wall is connected to and extends from the second and third wall. The second pair of rollers are further rotatably supported by the fourth wall. In some implementations, the first pair of rollers are rotatably supported by fasteners extending through a set of holes formed in the second wall. In some implementations, the first pair of rollers are bushings. In some implementations, the expandable portion includes a piston. In some implementations, the cable travels axially through the integral passage. 
         [0009]    Yet another implementation relates to a method for modifying a tire lift assembly. The method includes providing a tire lift assembly that includes a cable dispensing portion having a casting forming an integral passage and a cable extending through the integral passage of the casting of the cable dispensing portion. The method includes providing a guide assembly that includes a mounting plate, a support structure extending from the mounting plate, and a first pair of rollers. The support structure includes a first wall, a second wall, and a third wall defining an opening. The first wall is connected to and extends from the mounting plate. The second wall and the third wall are connected to and extend from the first wall. The second wall is opposite the third wall. The first pair of rollers are rotatably supported by the second wall and the third wall. The first pair of rollers are positioned on opposing sides of the opening defined by the first wall, the second wall, and the third wall. Each roller of the first pair of rollers rotates relative to the support structure when the cable contacts a roller of the first pair of rollers. The method further includes feeding an end of the cable through the opening defined by the first wall, the second wall, and the third wall. The method further includes connecting the mounting plate of the guide assembly to the casting of the cable dispensing portion of the tire lift assembly. 
         [0010]    In some implementations, the guide assembly further includes a second pair of rollers rotatably supported by the first wall. The second pair of rollers are positioned non-parallel to the first pair of rollers on opposing sides of the opening defined by the first wall, the second wall, and the third wall. In some implementations, the first pair of rollers are perpendicular to the second pair of rollers. In some implementations, the support structure further includes a fourth wall opposite the first wall. The fourth wall is connected to and extends from the second and third wall. The second pair of rollers are further rotatably supported by the fourth wall. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a tire lift assembly in accordance with the disclosure; 
           [0012]      FIG. 2  is a top view of the tire lift assembly of  FIG. 1 ; 
           [0013]      FIG. 3  is an end view of the tire lift assembly of  FIG. 1 ; 
           [0014]      FIG. 4  is a section view through a lift roller of the tire lift assembly of  FIG. 1 ; 
           [0015]      FIG. 5  is a bottom view of a guide assembly for the tire lift assembly of  FIG. 1 ; 
           [0016]      FIG. 6  is a side view of the guide assembly of  FIG. 5  with the pairs of rollers removed; 
           [0017]      FIG. 7  is a back view of the guide assembly of  FIG. 5  with the pairs of rollers removed; 
           [0018]      FIG. 8  is a back view of the guide assembly of  FIG. 5 ; 
           [0019]      FIG. 9  is a side view of the guide assembly of  FIG. 5 ; and 
           [0020]      FIG. 10  is a partial, enlarged assembly view of the guide assembly of  FIG. 5  installed on the tire lift casting of the tire lift assembly of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    In the description that follows, structures and features that are the same or similar as shown in the various views of the drawings are denoted by the same reference numerals throughout the several views for consistency and simplicity, but it should be appreciated that the various structures or features may differ that those shown. 
         [0022]    A tire lift assembly  100  is shown in  FIGS. 1-4 . In the illustrated embodiment, the tire lift assembly  100  is configured as an overhead lift or gantry that is mounted on a ceiling joist, which is generally denoted as joist  102 . The tire lift assembly  100  has a generally elongate shape that includes an expandable central portion  104 , which is flanked by a cable dispensing portion  106  at one end and a cable anchoring portion  108  at another end. Each end  106  and  108  is slidably connected with the joist through rollers or roller bearings  110  but other arrangements can be used. Each end  106  and  108  further includes a pulley  112 . The pulleys  112  guide a cable  114  along the length of the tire lift assembly  100  and down the cable dispensing portion  106 . 
         [0023]    During operation, extension or retraction of the expandable central portion  104  causes a lifting or lowering of a hook  118  connected on a free end of the cable  114 . An opposite end of the cable  114  is anchored at a mount  120  disposed on the cable anchoring portion  108 . As the lift is moving along the joist  102 , which can be embodied as a C-beam (see  FIG. 4 ), brackets  122  guide the two ends  106  and  108  along the joist  102  as the two ends  106  and  108  move towards or away from one another. To limit the travel of the lift  100  along the joist  102 , bumpers  124  are disposed on either end of the lift  100  and mounted to the joist  102 . The bumpers  124 , which may have resilient properties, prevent excessive travel along the joist  102  and help retain the roller bearings  110  engaged with the joist  102 . 
         [0024]    In the particular construction of the lift  100  shown here, the expandable central portion  104  is embodied as a piston  125 , which may operate under pneumatic power, but other types of power may be used such as hydraulic, electrical or mechanical. The piston  125  includes a first segment  126 , which forms a piston bore (not shown) therein, and a second segment  128 , which includes a piston plunger (not shown) that is slidably and sealably disposed within the piston bore such that two sealed chambers are formed within the bore on either side of the plunger, in the known fashion. Fluid lines  130 , which are in fluid communication with the two sealed chambers, one on each side, provide fluid under pressure causing the plunger to move within the bore, as is known, which in turn causes the expandable central portion  104  of the lift  100  to move and lift of lower the hook  118  via the cable, as previously discussed. As shown, control buttons  132  and  134  are mounted on an operator control handle  136  that is associated with the hook  118  and dangles off the free end of the cable  114  through a finial  138  and pivot pin  140 . The control buttons  132  and  134  associated with the handle  136  activate fluid valves  135  ( FIG. 1 ) via flexible lines  142  to provide pressurized fluid to the lines  130 . 
         [0025]    In the construction for the lift  100  described herein, either end of the lift  100  can be configured as the cable dispensing end  106  or the cable anchoring end  108 . As shown, either end includes a casting  200  that forms an integral passage  202  extending tangentially with respect to the pulley  112 , through which passage the cable  114  extends. On the cable dispensing end  106 , during operation, the extending and retracting of the piston  125  may impart lateral moments on the cable  114 . Moreover, the pin  140  and a weight such as a tire handing on the hook  118  may provide a swinging motion to the cable  114  as the cable  114  travels axially through the integral passage  202 , thus causing cable contact and rubbing with the material of the casting  200 , which leads to undue wear. 
         [0026]    To minimize or eliminate such wear on the cable dispensing end  106  of the lift  100 , a guide assembly  204  is provided. The guide assembly  204 , and its various components, are shown in  FIGS. 5-9 . In reference to these figures, the guide assembly  204  includes a mounting plate  206  having mounting holes  208  formed therein. Fasteners  210  ( FIG. 10 ) can extend through the mounting holes  208  and engage corresponding threaded openings formed in the casting  200  to mount the guide assembly  204  onto the cable dispensing end  106  of the lift  100 . 
         [0027]    The guide assembly  204  further includes a support structure  212  that rotatably supports a first pair  214  of elongate rollers  215  and a second pair  216  of elongate rollers  215 . Each roller  215  includes a centerline  218 , which also coincides with the respective roller&#39;s rotational axis, such that two parallel axes  218  are defined by the rollers  215  of the first pair  214 , and two parallel axes  218  are defined by the rollers  215  of the second pair  216 . In the illustrated embodiment, the axes  218  of the rollers  215  in the first pair  214  are perpendicular to the axes  218  of the rollers  215  in the second pair  216 , but any other angle can be used. For example, instead of the four rollers  215  forming a rectangle surrounding an opening  220 , when viewed from the top as shown in  FIG. 5 , the rollers can alternatively form a diamond, a triangle, etc. Moreover, although four rollers  215  are shown, fewer or more rollers can be used. In one contemplated embodiment, six or eight rollers are arranged in a closed pattern surrounding the opening  220 , while in a different embodiment, three rollers are arranged in a triangular configuration around the opening  220 . Any number or arrangement of rollers can be used to surround the opening, provided that rolling surfaces are disposed around the opening  220 . 
         [0028]    In the embodiment shown, the rollers  215  are mounted onto the support structure  212  by fasteners  222  that extend through and engage holes  224  formed in the support structure  212 . The support structure  212  is generally U- or C-shaped and includes a first wall  226 , which is connected to the mounting plate  206 , a second wall  228 , which is connected to the first wall  226  and extends away therefrom in a direction of the opening  220 , and a third wall  230 , which is connected to the first wall  226  opposite the second wall  228  and also extends away from the first wall  226  in the direction of the opening. A fourth wall (not shown) that is connected to the second and third walls  228  and  230  may also be used. The first, second and third walls  226 ,  228  and  230  in the illustrated embodiment surround the opening  220  such that, when the rollers  215  are mounted to the walls  226 ,  228  and  230 , the rollers will surround the opening. 
         [0029]    An enlarged detail view of the guide assembly  204  connected to a casting  200  of a lift  100  ( FIG. 1 ) is shown in  FIG. 10 . In this embodiment, two fasteners  210  (one visible) are used to connect the mounting plate  206  to the casting  200 , each of which is a ¼-20 bolt. The guide assembly  204  includes two socket head screws that are 6 mm diameter×45 mm long, and two screw shoulder socket head 6 mm diameter×40 mm long screws, for a total of four screws that make up the fasteners  222  along with four 5 mm hex lock nuts. The rollers  215  are made from four drill bushing steel Type P 0.25″ID×13/32″0D×1.38″ long bushings. The two single support rollers  215  by fasteners  222  include two lock external tooth 6M washers. The mounting plate  206  and the material of the first  226 , second  228 , third  230  and fourth walls is made of cut and shaped sheet metal made from steel and having a nominal thickness of 0.12 in. stock. 
         [0030]    The guide assembly  204  is mounted such that the cable  114  passes through the opening  220  ( FIG. 5 ). In this way, any deflection of the cable  114 , e.g. by swinging, during service will cause contact to occur between the cable  114  and rollers  215  rather than with the material of the casting  200 . The rolling capability of the rollers  215  avoids sliding contact with the cable  114 , which eliminates cable fraying and wear in the casting  200 . Advantageously, the guide assembly  204  may be installed in already worn castings  200  because further contact of the cable  114  with the casting  200  will be precluded when the guide assembly  204  is used. 
         [0031]    All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
         [0032]    The use of the terms “a” and “an” and “the” and “at least one” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
         [0033]    Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.