Abstract:
A transmission lift arm to facilitate the safe lifting and/or lowering of a transmission from or into a transmission jack. The transmission lift arm is provided in pairs and each is adapted for attachment to a transmission bell housing utilizing threaded rods secured thereto. The lift arms may be adjustably spaced apart on the lift arm of a lift truck to accommodate various spacings is the bell housing holes into which the threaded rods are placed and secured. The transmission arms may also be provided in a variety of sizes to mount to different lift bar sizes and/or to have different size threaded rods to accommodate a wide range of motor vehicle transmissions. In alternate embodiments, transmission lift arms having an adjustable opening may be used to accommodate different lift bar dimensions.

Description:
FIELD OF THE INVENTION 
     The invention pertains to apparatus adapted for lifting heavy, specialized objects and, more particularly, to a device for attachment to the bell housing of a motor vehicle transmission to allow safe lifting thereof using a lift truck. 
     BACKGROUND OF THE INVENTION 
     In motor vehicle repair shops, one task often performed is the repair or replacement of a vehicle&#39;s transmission. The transmission is typically both heavy and awkward to lift. Typically an overhead hoist or winch is used to lift a transmission using chains or other lifting straps placed around the transmission body. However, in some repair shops called upon to remove a transmission from a vehicle, such a hoist is unavailable. 
     When no hoist is available, a hydraulic transmission jack is at times used to lower a transmission from the vehicle that may be raised above the floor on a lift. This is an intricate procedure because transmission jacks rarely interface well with the body of a typical transmission and the transmission is often balanced precariously on the jack. Transmissions typically have components such as control arms protruding from their bodies—components that could easily be damaged if the transmission were to fall off the jack. In addition, typical hydraulic floor jacks are prone to rolling on the floor and must be stabilized, typically by a person. 
     To remove (or install) a transmission typically requires at least three persons to safely accomplish the removal or installation. Three people may not be available when it is time to remove or install a transmission so a repair job may be stalled until additional help is available. Even if other mechanics are available, they must typically be pulled from whatever repair job they are performing thereby extending the time required to complete those jobs. Finally, because of the shape and weight of a typical motor vehicle transmission, raising or lowering the transmission imposes less than ideal body mechanics on the mechanic or other person involved. This situation often leads to back strain or other back injuries. 
     DISCUSSION OF THE RELATED ART 
     Several attempts to provide apparatus and method for removing and installing motor vehicle transmissions may be found in the prior art. For example, U.S. Pat. No. 2,523,734 for TRANSMISSION GRIPPING DEVICE, issued Sep. 26, 1950 to John O. Stephenson et al. shows an apparatus for use with a floor jack to grip and stabilize the body of a transmission. 
     U.S. Pat. No. 3,700,132 for FLOOR HOIST, issued Oct. 24, 1972 to James R. Waters teaches a low profile portable hydraulic hoist for handling heavy structures in cramped quarters. The WATERS hoist is not specifically adapted to motor vehicle transmissions. 
     U.S. Pat. No. 5,071,183 for TOOL FOR INSTALLING CUTTING BLADES ON GRADERS, issued Dec. 10, 1991 to Jerry L. McDermott et al. provides a tool for temporarily supporting a cutting blade in a correct angular orientation to facilitate its installation on a grader. 
     U.S. Pat. No. 5,303,966 for TORQUE CONVERTER RETAINING TRANSMISSION TRANSPORT DEVICE, issued Apr. 19, 1994 to Larry M. Robinson teaches a device for retaining a torque converter within a bell housing, the device being attachable to a transmission and providing at least one handle to facilitate carrying a transmission. 
     U.S. Pat. No. 5,352,056 for HOIST RING WITH SELF-LOCK RETAINING RING, issued Oct. 4, 1994 to William M. Chandler shows hoist ring having a central screw having a head at a first end and a threaded shank at an opposite end. 
     U.S. Pat. No. 5,732,991 for CAST ARTIFACT HANDLING ASSEMBLY, issued Mar. 31, 1998 to Gary Tsui provides a safety hoist ring removably attachable to an anchor embedded in a concrete structure. 
     U.S. Pat. No. 5,887,922 for ADJUSTABLE LIFTING BAIL FOR FLUID COMPRESSOR, issued Mar. 30, 1999 to Dean P. Hendrix et al. teaches a lifting bail adapted to be made integral with a machine having a center of gravity and having a lift eye plate adjustably placeable near the center of gravity. 
     United States Published Patent Application No. 2004/0108738 for FORKLIFT CLAMP AND CHOKER SOFTENER, published Jun. 10, 2004 upon application by Marvin C. Marry provides a sleeve for placement on the fork of a lift truck to support and protect a sling for moving odd-shaped or heavy objects. 
     U.S. Pat. No. 6,766,991 for DRY SUMP PUMP BRACKET, issued Jul. 27, 2004 to Derek Nance et al. teaches a bracket mountable on the transmission on a race car for supporting a sump oiling pump. 
     U.S. Pat. No. 7,020,943 for LIFT TOOL, issued Apr. 4, 2006 to David W. Cronk provides a lift tool useful for installing a clutch assembly or flywheel into a vehicle bell housing. 
     None of these patents or the published patent application, taken singly, or in any combination are seen to teach or suggest the novel transmission lift arm of the present invention. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention there is provided a transmission lift arm to facilitate the safe removal and/or installation of a motor vehicle transmission from or to a transmission jack. The novel transmission lift arm is provided in pairs and each is adapted for removable attachment to the transmission utilizing threaded rods placed through preexisting holes in the bell housing portion of the transmission. The lift arms may be secured to the bell housing, typically using washers and nuts. The lift arms may be adjustably spaced apart on the lift arm of lift truck to accommodate various spacings in the bell housing holes into which the threaded rods are placed and secured. The transmission arms may also be provided in a variety of sizes to mount to different lift bar sizes and/or to have different size threaded rods to accommodate a wide range of motor vehicle transmission. In alternate embodiments, transmission lift arms having an adjustable opening may be used to accommodate different lift bar dimensions. 
     The novel transmission lift arms of the invention allow a single person to safely lift and/or lower a transmission while minimizing the possibility of damage to the transmission and injury to the mechanic removing or installing the transmission. 
     It is, therefore, an object of the invention to provide a transmission lift arm to facilitate lifting and lowering a motor vehicle transmission from or onto a transmission jack. 
     It is another object of the invention to provide a transmission lift arm that may be removably attached to the bell housing of the transmission being removed or installed. 
     It is an additional object of the invention to provide a transmission lift arm that has a threaded rod adapted for insertion into and retention within a hole in a bell housing of the transmission being removed or installed. 
     It is a further object of the invention to provide a transmission lift arm that is sized and configured for removable installation onto the lift bar of a lift apparatus. 
     It is a still further object of the invention to provide transmission lift arms in pairs, each one of the pair of transmission lift arms being attached to opposing ones of the bell housing holes and slidably spaced apart on the lift bar of the lift apparatus. 
     It is yet another object of the invention to provide a transmission lift arm that is strong enough to support the weight of a transmission and inexpensive to manufacture. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
         FIG. 1  is a side elevational, schematic view of one embodiment of a transmission lift arm in accordance with the invention; 
         FIG. 2  is a top plan, schematic view of the transmission lift arm of  FIG. 1 ; 
         FIG. 3  is a front elevational, schematic view of the transmission lift arm of  FIG. 1 ; 
         FIG. 4  is a side, perspective view of a pair of transmission lift arms of  FIG. 1  in place on and supported by a lift bar of a lift truck and attached to a bell housing; 
         FIG. 5  is a rear, perspective view of a pair of transmission lift arms, a lift bar of a lift truck, and the bell housing of  FIG. 4 ; 
         FIG. 6   a  is a side elevational view of a leg component of an adjustable transmission lift arm assembly; 
         FIG. 6   b  a top plan view of a leg component of the adjustable transmission lift arm of  FIG. 6   a;    
         FIG. 6   c  is a front elevational view of the leg component of  FIG. 6   a;    
         FIG. 6   d  is an exploded, perspective, schematic view of an alternate embodiment of the adjustable transmission lift arm in accordance with the invention; and 
         FIG. 6   e  is an alternate embodiment of a component of the adjustable transmission lift arm of  FIG. 6   
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention provides an adapter for temporarily securing a bell housing or similar structure, typically of a motor vehicle transmission or the like to a lift bar of a lift truck or similar device. The novel transmission lift arm allows the safe lifting or lowering a transmission onto or from a conventional transmission jack by a single mechanic. 
     Referring first to  FIGS. 1 ,  2  and  3 , there are shown side elevational, top plan, and front elevational schematic views, respectively, of one embodiment of a transmission lift arm in accordance with the invention, generally at reference number  100 . 
     Transmission lift arm  100  consists of a U-shaped member  102  consisting of an upper leg  104 , a lower leg  106 , and a spine  108  that is typically formed from a flat web of steel or another suitable material. 
     A pair of triangular braces, upper brace  110  and lower brace  112  and a vertical stiffener  114  are fastened to U-shaped member  102  by welding shown schematically at reference number  120 . It will be recognized that fastening processes other than welding may be known to those of skill in the art and any suitable fastening process may be substituted for welding. The invention is, therefore, not limited to the welding fastening process chosen for purposes of disclosure. Rather the invention includes any suitable fastening process or material. 
     A projecting member  116  is attached to upper leg  104 , typically by welding  120 . Projecting member  116  is typically a threaded rod adapted to receive a nut or similar fastener, neither shown, on a distal end thereof. It will be recognized that projecting member  116  may be formed from a non-thread bearing rod. Consequently, the invention is not considered limited to the threaded rod chosen for purposes of disclosure. 
     Upper leg  104  and lower leg  106  are spaced apart by a distance  118  chosen to accept a particular dimension of a lift bar, not shown, of a lift truck with which lift arm assembly  100  will be used as discussed in detail hereinbelow. 
     The transmission lift arm  100  is adapted to mount on a single size lift arm, not shown, having a height substantially equal to distance  118 . In a particular shop, more than one lift truck may be present, different lift trucks having different size lift arms. This situation results in sets of transmission lift arms  100  in different sizes being required to accommodate the different lift arm sizes. This problem may also be overcome by providing an adjustable transmission lift arm. 
     Referring now also to  FIGS. 6   a ,  6   b , and  6   c , there are shown side elevational, top plan, end front elevational views, respectively of a leg component  202  that may be used to form an adjustable lift assembly  200  ( FIG. 6   d ). Leg component  202  consists of a flat, rectangular, horizontal member  204  and a vertical member  206  having a rectangular region  206   a  and a contiguous substantially triangular portion  206   b . It should be noted that in an alternate embodiment an outside upper corner of rectangular portion  206   a  may be rounded. Vertical member  206  is attached to a midpoint along a major axis of rectangular horizontal member  204 . A pair of through holes  208   a ,  208   b  are formed proximate an upper end of vertical member  206 . 
     Vertical member  206  is typically attached to flat, rectangular, horizontal member  204  along by welding, not shown. Vertical member  206  is arranged such that a major axis of rectangular portion  206   b  is perpendicular to a major axis of flat, rectangular, horizontal member  204 . 
     A threaded rod  116 , described in detail hereinabove, is affixed to an upper surface of flat, rectangular, horizontal member  204 . 
     A lower edge of triangular portion  206   a  is aligned with and affixed to an upper surface of flat, rectangular, horizontal member  204 . 
     A pair of leg components  202   a ,  202   b  is utilized to form an adjustable transmission lift arm  200 . Leg components  202   a  and  202   b  are mirror images of one another. While only leg component  202   a  has been described in detail, leg component  202   b  is identical except for the reversed relationships of flat, rectangular, horizontal member  204 , vertical member  206 , and threaded rod  118 . 
     Leg components  202   a ,  202   b  are adapted to be linked by connecting bars  210   a ,  210   b . Connecting bars  210   a ,  210   b  are typically identical to one another. However, as discussed hereinbelow, opposite ends of adjustable connector bars  210   a ,  210   b  are connected to respective ones of leg components  202   a ,  202   b.    
     Referring now also to  FIG. 6   d , there is shown an exploded, perspective, schematic view of an alternate embodiment of the transmission arm in accordance with the invention, generally at reference number  200 . Transmission lift arm  200  has an adjustable throat (i.e., inside space between the leg components  202   a ,  202   b  to allow its use with different lift trucks having different size lift bars. 
     A pair of connecting bars  210   a ,  210   b  each having a proximal end and a distal end and pair of spaced apart through holes  212  are disposed along a major axis of each connecting bar  210   a ,  210   b  proximate their respective proximal ends. Each connecting bar  210   a ,  210   b  also has a central slot  224  extending along the major axis, each said slot beginning at a point beyond a lower one of the pair of spaced apart holes  212  and continuing along the major axis to a point near the distal end of each of said pair of connecting bars  210   a ,  210   b . Spaced apart through holes  212  are configured for alignment with spaced apart holes  208   a ,  208   b  of leg components  202   a ,  202   b.    
     Bolts, washers, and nuts, not shown, or similar fastening systems, not shown, believed to be well known to those of skill in the art may be used to assemble connecting bars  210   a ,  210   b  to respective leg components  202   a ,  202   b . Arrow  214  shows the path of a bolt or similar fastener through connecting bar  210   a , leg component  202   a , and connecting bar  210   b . Likewise, arrow  216  shows the path of a connecting bolt or the like through connecting bar  210   a , leg component  202   b , and connecting bar  210   b . It should be noted that paths  214 ,  216  show only a single fastener path. Typically, two fasteners (one through each of the two spaced apart holes  212 ) are used at each of leg components  202   a ,  202   b  mating with respective ones of spaced apart holes  208   a ,  208   b . This construction prevents possible rotation of connecting bars  210   a ,  210   b  with respect to either of leg components  202   a ,  202   b.    
     It should be noted that the connector bars  210   a ,  210   b  are installed in an inverted relationship with respect to one another. This inverted relationship of connecting bars  210   a ,  210   b  with respect to one another helps maintain an aligned relationship between leg components  202   a ,  202   b  and avoids pinching as leg components  202   a ,  202   b  are moved toward or away from one another to adjust the space therebetween. 
       FIG. 6   e  shows an alternate embodiment of a connecting bar  218  suitable for use in implementing an adjustable transmission arm  200 . Adjustable connecting bar  218  has a series of spaced apart holes  220  along a major axis thereof. The spacing  222  of holes  220  is chosen to match the spacing of spaced apart holes  208   a ,  208   b  in leg component assemblies  202   a ,  202   b . Consequently, spaced apart holes  220  may readily be aligned with any two of spaced apart  208   a ,  208   b  to create a number of different, discrete spacings between leg components  202   a ,  202   b.    
     Referring now to also  FIGS. 4 and 5  the use of transmission lift arms  100  or  200  of the invention is now described.  FIG. 4  is a side, perspective view of a pair of transmission lift arms of the invention in place on and supported by a lift bar  152  of a lift truck, not shown, and attached to a typical bell housing  154 , generally at reference number  150 .  FIG. 5  is a rear, perspective view of a pair of transmission lift arms, lift arm, and bell housing of  FIG. 4 . It should be noted that neither a lift truck, not shown, nor lift bar  152  forming a part thereof nor bell housing  154  form any part of the invention and are merely included to illustrate a typical operating environment for transmission lift arms  100  or  200 . 
     In operation, a pair of transmission lift arms  100  is selected to match the height of the lift arm or bar  152  of the lift apparatus. Alternately, a pair of adjustable transmission lift arms  200  is each adjusted to match the height of lift bar  152 . Transmission lift arms  100  or  200  are them disposed in a spaced apart relationship on lift arm  152 . The space between a first one of a pair of transmission lift arms  100  or  200  and a second one of the pair of transmission lift arms  100  or  200  is chosen to correspond to the spacing between holes  156  in transmission bell housing  154 . 
     Next, lift arm  152  carrying the pair of spaced apart transmission lift arms  100  or  200  is maneuvered so as to align threaded rods  116  with holes  156  in bell housing  154 . Once aligned, threaded rods  116  are slid into and through holes  156  until their distal ends protrude on the other side of transmission bell housing  152 . Once protruding, a washer, not shown, may be slid onto each of protruding threaded rods  116  and a nut, not shown, may be threaded onto each of protruding threaded rods  116 . It is believed that nuts and washers are well known to those of skill in the art and are not further discussed herein. It will be recognized that chosen nuts and washers must be compatible with the diameter and/or thread configuration of threaded rods  116 . The nuts, not shown, may be used to draw transmission bell housing  152  against transmission lift arm  100  or  200  and retain transmission bell housing  152  in that position. 
     Once secured, lift bar  152  may be manipulated to lift or lower transmission bell housing  152  as desired. 
     It will be recognized that while a transmission bell housing  152  has been chosen for purposes of disclosure, that the novel transmission lift arms  100 ,  200  may be adapted to interact with other items having a hole pattern that may be engaged by threaded rods  116 . Consequently, the invention is not considered limited to transmission bell housings. Rather, the novel transmission lift arms and method may be used to raise or lower any other device having accessible holes to engage threaded rods  116  of transmission lift arms  100 ,  200 . 
     The use of the novel transmission left arms  100  or  200  of the invention typically allows a single person to safely manipulate a transmission. Heretofore, two, often three persons were required to perform the same task and there were inherent safety risks associated with the lowering or raising operations. 
     Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the example chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention. 
     Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.