Abstract:
A universal harmonic balancer installation kit includes a collection of threaded rods and compatible threaded nuts correlated with each of the threaded rods and sized to position and engage a bushing against the hub of a harmonic balancer to thereby drive the balancer onto the end of a crankshaft. Various spacers and washers may be used in combination with the bushing and nuts to accommodate harmonic balancers of various size and configuration in combination with crankshafts having threaded installation openings of various sizes.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     In a principal aspect, the present invention relates to a tool kit for installing harmonic balancers upon the end of the crankshaft of an internal combustion engine.  
         [0002]     Typically, internal combustion engines incorporate a crankshaft with a harmonic balancer attached to one end of the crankshaft. Generally, a harmonic balancer comprises a cylindrical plate with a center hub having a hub opening to enable placement of the balancer over the end of a crankshaft. Heretofore, the application or installation of a harmonic balancer on the end of a crankshaft has been accomplished by engaging a threaded stud with an opening in the end of the crankshaft, placement of the harmonic balancer over the threaded stud and engagement of a nut with the harmonic balancer to drive the balancer onto the end of the crankshaft. Because the design of harmonic balancers and crankshafts vary from engine to engine, the utilization of a single installation tool to install harmonic balancers on multiple engines has not been possible. In an effort to overcome this problem, tool manufacturers developed kits which include an adapter designed to accommodate variously sized threaded openings in the end of a crankshaft having various thread pitches. Applicants&#39; assignee has made and sold such a kit, Model No. 52200, “Harmonic Balancer Installer”, Lisle Corporation, Clarinda, Iowa. Apparatus of this general nature is also disclosed in expired U.S. Pat. No. 4,457,061 entitled “Harmonic Balancer Installer” issued Jul. 3, 1984, which is incorporated herewith by reference.  
         [0003]     The use of such kits for the installation of harmonic balancers on the ends of various crankshafts has been successful. However, such kits are not universal. This results because of the numerous shapes and types of harmonic balancers available for internal combustion engines as well as the shape and configuration of the openings in the end of a crankshaft and the multiplicity of harmonic balance designs. Thus, there has developed a need for a universal harmonic balancer installation kit which will accommodate virtually all sizes and shapes of harmonic balancers as well as harmonic balancers having variously designs and crankshafts having various sized threaded openings to facilitate the installation of a harmonic balancer.  
       BRIEF SUMMARY OF THE INVENTION  
       [0004]     Briefly, the present invention comprises a harmonic balancer installation kit which includes a plurality of uniform diameter, threaded rods or studs with a polygonal drive at one end of each rod or stud. The kit further includes a bushing having a throughbore adapted to cooperate any one of a plurality of nuts. A separate nut is included for cooperation with each of the separate rods. Preferably, each of the nuts includes a cylindrical neck section which fits through the throughbore of the bushing so as to maintain alignment of the bushing and nut against the hub of a harmonic balancer that is being installed. Optional spacers and washers may be incorporated and positioned intermediate the drive nut and bushing to facilitate the universality of the installation kit.  
         [0005]     In use, a stud or rod is chosen for threading into the end of a crankshaft. The choice of the stud or rod is based upon matching the thread size of the rod with the thread size of the opening in the end of the engine crankshaft. Next, a threaded nut compatible with and correlated to the thread size of the rod is threaded onto the rod. Then, a bushing and a harmonic balancer are placed over the rod adjacent the nut. The threaded nut preferably includes a cylindrical neck section which fits through the throughbore of the bushing so as to align the bushing properly on the rod and to also align the harmonic balancer. Additional spacer and/or washers may be inserted between the nut and the bushing to facilitate alignment and engagement of the bushing against the harmonic balancer. The rod is then threaded into the crankshaft opening. The nut is then tightened onto the rod to drive or push the harmonic balancer onto the end of the crankshaft of the internal combustion engine. The nut may then be removed from the rod. The polygonal end of the rod facilitates maintaining the rod in a fixed position when driving the nut onto or removing the nut from the rod. After removal of the nut from the rod, the remaining elements including the bushing, washer and spacers may be removed from the rod. The rod itself may then be removed from the end of the crankshaft by engaging the polygonal drive at the end of the rod and unthreading the rod from the threaded opening in the distal end of the crankshaft. A bolt is then threaded into the crankshaft to retain the harmonic balancer.  
         [0006]     Thus, it is an object of the invention to provide an installation kit for harmonic balancers of the type used in combination with internal combustion engines.  
         [0007]     Further, it is an object of the invention to provide an installation kit for harmonic balancers wherein the kit is comprised of a plurality of threaded rods, each rod capable of providing a connection to and to be threaded into the end of a crankshaft.  
         [0008]     Another object of the invention is to provide a universal harmonic balancer installation kit which includes threaded rods, a bushing with a generally large throughbore, and drive nuts having a cylindrical section compatible with the bushing throughbore and further including compatible threads for engaging a correlated or compatible rod.  
         [0009]     Another object of the invention is to provide a universal installation kit which is easy to use, economical, rugged and capable of utilization with substantially any and all harmonic balancer designs and engine crankshaft designs.  
         [0010]     These and other objects, advantages and features of the invention will be set forth in the detailed description which follows.  
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0011]     In the detailed description which follows, reference will be made to the drawing comprised of the following figures:  
         [0012]      FIG. 1  is a sectional view depicting the crankshaft and a first type of harmonic balancer;  
         [0013]      FIG. 2  is a sectional view of an alternative design for a harmonic balancer and crankshaft;  
         [0014]      FIG. 3  illustrates yet a further construction or design of a harmonic balancer;  
         [0015]      FIG. 4  depicts another type of harmonic balancer and crankshaft combination;  
         [0016]      FIG. 5  is a cross sectional view of typical elements incorporated in the harmonic balancer installation kit of the invention as combined for the installation of a particular type of harmonic balancer;  
         [0017]      FIG. 6  is an exploded isometric view of the various elements includable in a harmonic balancer installation kit of the invention; and  
         [0018]      FIGS. 7 through 18  are isometric views illustrating the sequential steps in the use of the tool kit of the invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]      FIGS. 1-4  are cross sectional views of various types of harmonic balancers that may be fitted onto a crankshaft by the tool kit of the invention. The balancers disclosed in  FIGS. 1-4  are exemplary only and illustrate the problem addressed by the tool kit of the invention; namely, the problem of developing a means for attaching harmonic balancers of various size and construction using a tool kit comprised of the minimum number of elements or parts. Thus, referring to  FIG. 1 , there is depicted a harmonic balancer  10  which includes a generally cylindrical rim or plate  12  and a center hub  14  with a counterbore  16  designed to fit over the end  18  of a crankshaft  19 . The harmonic balancer  10  is inserted onto the crankshaft  19  and retained thereon by a bolt  21 . The harmonic balancer of  FIG. 1  includes a bore  20  through which the bolt  21  may fit to engage a threaded opening  22  in the end of the crankshaft  19 .  
         [0020]      FIG. 2  illustrates yet another type of construction of a harmonic balancer. Here a balancer  24  includes a constant diameter bore  26  which fits over the end  18  of the crankshaft  28 . Such a design is found, for example, in various General Motors vehicles including a 1991-1993 Oldsmobile Cutlass, Pontiac Grand Prix and Chevrolet Lumina.  
         [0021]      FIG. 3  illustrates yet another type of harmonic balancer construction. A harmonic balancer  30  includes a shaped counterbore  32  which fits over the end of crankshaft  34 . A bolt fits into the counterbore opening  36  associated with the bore  32 . The harmonic balancer of the profile depicted in  FIG. 3  can be found in the 1989-1995 Mercury Sable and Ford Taurus vehicles.  
         [0022]      FIG. 4  illustrates yet a further harmonic balancer construction. A harmonic balancer  40  includes a bore  42  which fits over the end of the crankshaft  44 . A bolt (not shown) fits through the bore  42  and the head of the bolt will fit into the counterbore section  46 . A harmonic balancer of this type is found in the 1989-1995 Mercury Cougar and 1989-1995 Ford Thunderbird.  
         [0023]     Various other types of harmonic balancer configurations, sizes and shapes are available and used in various types of internal combustion engines. Typically, the size of the threaded opening  48 , for example, in  FIG. 4  for each of the crankshafts, for example  44  in  FIG. 4 , associated with the harmonic balancer are generally of distinct bore sizes. Thus, the size of the threaded opening, e.g.  48  in  FIG. 4 , will vary from engine to engine. The diameter of the crankshaft will also vary from engine to engine. The shape, depth and dimensions of the bore, e.g.  42 ,  46  in  FIG. 4 , will vary from balancer to balancer. Thus, the installation of the harmonic balancer becomes a challenging matter for a mechanic repairing an internal combustion engine.  
         [0024]     The present invention constitutes a kit which enables a mechanic to affix literally any harmonic balancer onto the end of any compatible crankshaft.  FIG. 5  illustrates a typical configuration of elements utilized from such a kit. Referring to  FIG. 5 , a harmonic balancer  60  is applied to the end of a crankshaft  62  by utilizing a threaded rod shaft or stud  64  having a polygonal drive end  66 . The threaded shaft  64  is sized to fit into the threaded opening  68  in the end of the crankshaft  62 . It also fits through the center axial bore  70  in the hub of the harmonic balancer  60 . The harmonic balancer  60  further includes a bore  72  which is received on the end of the crankshaft  62 . The kit of the invention includes a thrust bearing or bushing  74  which is a generally annular member having an internal diameter throughbore  76  that is typically larger than the diameter of the threaded rod  64 . A washer  78  may be fitted against the bushing  74  and a threaded thrust nut  80  having a polygonal head  82  and a cylindrical section  84  fits through a throughbore opening  86  in the washer  78  and is sized to also be received by the throughbore  76  of the thrust bearing or bushing  74 . This facilitates alignment of the thrust bearing or bushing  74  as well as the washer  78 . In the embodiment of  FIG. 5 , the use of a washer  78  is not necessary. However, the individual installing the harmonic balancer may desire to use such a washer  78  in the combination.  
         [0025]      FIG. 6  illustrates additional elements which may be included in the installation kit. Thus, in addition to the thrust bearing or bushing  74  and washer  78 , a spacer member in the form of a cylindrical tube  90  may be utilized. The threaded nut  80  will then fit against the spacer tube  90  or alternatively, an additional washer may be inserted between the threaded nut  80  and the spacer tube  90 . In the embodiment depicted in  FIG. 6 , the washer  78  includes an annular recess  79  which cooperates with the spacer  90  to maintain alignment thereof along a center line axis  65  of the threaded shaft or rod  64 .  
         [0026]     Note that the threaded rod or shaft  64  is threaded substantially along the entire length but for the polygonal drive shaft section  66 . As a consequence, the construction of the device is simplified inasmuch as the threads of the shaft  64  match the threads of bore  68  of the crankshaft  62  as well as the threads of the threaded nut  80 .  
         [0027]     In a preferred embodiment of the kit, following elements are included:  
                                                           Thrust Bearing   ⅝-18 Nut    9/16-18 Stud           1⅝″ Washer   ¾-16 Nut   ⅝-11 Stud           2⅛″ Tube   M10 × 1.5 Nut   ⅝-18 Stud           2⅛″ Stepped Washer   M12 × 1.5 Nut   ¾-16 Stud           1⅝″ Tube   M12 × 1.75 Nut   M10 × 1.5 Stud           1⅝″ Stepped Washer   M14 × 1.5 Nut   M12 × 1.5 Stud           1 43/64 Spacer   M14 × 2.0 Nut   M12 × 1.75 Stud           2 1/16″ Spacer   M16 × 1.5 Nut   M14 × 1.5 Stud            7/16-20 Nut   M16 × 2.0 Nut   M14 × 2.0 Stud           ½-20 Nut   M18 × 1.5 Nut   M16 × 1.5 Stud            9/16-18 Nut    7/16-20 Stud   M16 × 2.0 Stud           ⅝-11 Nut   ½-20 Stud   M18 × 1.5 Stud                      
 
         [0028]      FIGS. 7-18  depict the method of use of the elements of the kit of the invention. Referring first to  FIG. 7 , the mechanic will choose an appropriate rod or stud and apply grease to the threads to prevent seizing. Next, a nut is hand threaded onto the rod from the threaded end of the rod rather than the end with the drive  66 .  
         [0029]     Next, referring to  FIG. 8 , a washer or combination or stepped washers, spacers and the thrust bearing or bushing are chosen by the mechanic based upon the balancer. The elements are then placed on the rod.  
         [0030]     Referring to  FIG. 9 , if necessary, a spacer may be used to fit against the inside rim of the bore through the harmonic balancer to provide for proper access and spacing of the nut  80  from the hub of the harmonic balancer.  
         [0031]     As shown in  FIG. 10 , it is necessary to check the manner in which the various component parts are fitted with respect to the harmonic balancer to insure that access is maintained with respect to the nut  80  so that the nut  80  may be turned to push the harmonic balancer onto the end of the crankshaft.  
         [0032]     As depicted in  FIG. 11 , the washer or washers, bushing and so on are all placed upon the rod or shaft with the flats or drive portion of the rod positioned away from the crankshaft. Next, as depicted in  FIG. 12 , the spacer on the front of the assembly is placed over the rod or shaft and then the harmonic balancer is placed over the rod or shaft.  
         [0033]     As shown in  FIG. 13 , the rod is then hand-tightened into the bolt hole of the end of the crankshaft until it bottoms out. The nut  80  is then tightened by hand as depicted in  FIG. 14  to move the harmonic balancer into position on the end of the crankshaft. As depicted in  FIG. 15 , the nut is tightened by a wrench until the harmonic balancer is in place on the crankshaft.  
         [0034]     As shown in  FIG. 16 , the next step is to remove the tool by loosening of the nut  80  and then loosening and removal of the stud, rod or shaft  64  as depicted in  FIG. 17 . A wrench may be used if necessary.  
         [0035]     As depicted in  FIG. 18 , the final step is to insert the bolt  100  which is used to maintain the harmonic balancer connected to the crankshaft.  
         [0036]     There has been set forth a preferred embodiment of the invention. However, the kit of the invention may be modified, for example, by using spacers of various sizes and dimension without departing from the spirit and scope of the invention. The invention is therefore to be limited only by the following claims and equivalents thereof.