Abstract:
A serpentine belt tool for release of tension on a serpentine belt tensioned by a biased idler pulley mounted on a spring loaded arm includes first and second manually operable handles which may alternately be engaged with an extension bar keyed to the center spindle of the idler pulley to thereby provide ratchet like action and movement of the extension bar releasing the tension of the idler pulley on the belt.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     In a principal aspect, the present invention relates to a tool which is utilized to control or adjust the tension of a serpentine belt, particularly a serpentine belt associated with an internal combustion engine.  
         [0002]     Modern diesel and internal combustion engines typically include closed loop belts which have a serpentine shape inasmuch as they fit around and connect a plurality of pulleys associated with various operating components or elements of the engine. Often, a serpentine belt is tensioned by means of an idler pulley mounted at the end of a cantilever, spring loaded or spring biased arm. When seeking to repair or replace a component of an engine associated with a serpentine belt driven pulley, or when seeking to replace a serpentine belt, it is necessary to release the tension of the idler pulley on the belt.  
         [0003]     Various tools have been developed to effect such release, including tools heretofore manufactured by Lisle Corporation and identified as Serpentine Belt Tools, Product No. 57800 and Product No. 57900. Such prior art serpentine belt tools comprise an elongate, flat bar stock handle having one or a pair of configured openings at one end designed to engage the center axle of an idler pulley. The elongate handle may then be manipulated to pivot the idler pulley and spring biased cantilever arm to release the tension on a serpentine belt thereby permitting removal of the belt. Such tools further may include handle extensions which are bolted to the elongate handle to provide further access to an idler pulley located in a hard to reach area of an engine compartment.  
         [0004]     Nonetheless, there has remained a problem associated with the release of tension on serpentine belts. That is, for example, the amount of movement of the tension release elongate handle may be restricted in an engine compartment by virtue of the components associated with the engine or by the configuration of the engine compartment itself. Thus, there has developed the need for a serpentine belt tool which will address such issues, among others.  
       SUMMARY OF THE INVENTION  
       [0005]     Briefly the present invention comprises a serpentine belt tool for release of tension upon a serpentine belt that is tensioned by a biased idler pulley. The tool comprises first and second handles which may alternately be engaged with an extension bar that is keyed or fixed to the center spindle or shaft of the idler pulley to thereby provide ratchet-like action and incremental movement of the extension bar. Such incremental movement is transmitted to the idler pulley and the associated spring biased cantilever arm to effect release of tension on the serpentine belt. The actuation handles each include keyed openings designed to be engaged with and disengaged from keyed elements of a pivot pin projecting from the extension bar. The keyed openings of the actuation handles may be offset to enable smaller degrees of incremental movement required in highly restricted access situations.  
         [0006]     Thus, it is an object of the invention to provide an improved serpentine belt tool which is especially useful for release of tension from an idler pulley on a belt when the pulley is located in restricted or hard to reach areas in an engine compartment.  
         [0007]     It is a further object of the invention to provide an easily used, rugged, and economical serpentine belt tool.  
         [0008]     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  
       [0009]     In the detailed description which follows, reference will be made to the drawing comprised of the following figures:  
         [0010]      FIG. 1  is an isometric view of a collection of prior art serpentine belt tools;  
         [0011]      FIG. 2  is an exploded isometric view of an embodiment of the serpentine belt tool of the invention;  
         [0012]      FIG. 2A  is an exploded plan view of the tool of  FIG. 2 ;  
         [0013]      FIG. 3  is a side view of the extension bar of the tool of  FIG. 2 ;  
         [0014]      FIG. 4  is a plan view of the extension bar of  FIG. 3 ;  
         [0015]      FIG. 5  is a side view of an actuation handle of the tool of  FIG. 2 ;  
         [0016]      FIG. 6  is a plan view of the actuation handle of  FIG. 5 ;  
         [0017]      FIG. 7  is a plan view of a pivot pin associated with the extension bar of the tool of the embodiment of  FIG. 2 ;  
         [0018]      FIG. 8  is an end view of the pin of  FIG. 7 ;  
         [0019]      FIG. 9  is an isometric view depicting the mode of operation of the tool of the invention;  
         [0020]      FIG. 9A  is a cross sectional view of the elements of the invention depicting the manner in which one of the handles interacts with the driving pin element;  
         [0021]      FIG. 9B  is a sectional view depicting the interaction of the second handle with the pin;  
         [0022]      FIG. 10  is a plan view of an alternate pivotal pin for the extension bar;  
         [0023]      FIG. 11  is a side view of a first extension handle depicting the profile of the keyed opening that co-acts with the pivot pin of  FIG. 10  or  FIG. 7 ;  
         [0024]      FIG. 12  is a side view of a second extension handle used in combination with the handle of  FIG. 11  and depicting an offset of the keyed opening that co-acts with the pivot pin;  
         [0025]      FIG. 13  is a cross sectional view of a pivot pin of the type depicted in  FIG. 10 ; and  
         [0026]      FIG. 14  is a side view of the ends of a first and second extension handle designed to interact with a pin of the type depicted in  FIG. 10  and  FIG. 13 .  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0027]      FIG. 1  illustrates a collection of various prior art tools. The tools comprise elongate, flat bar-shaped handles  10  having a manual gripping end  12  and key openings  14  and  16  at the distal end  15  for engagement with the shaft head  17  of the center shaft or axial rod of an idler pulley  20 . In use, one keyed opening  14  or  16  is engaged with idler pulley shaft head  17  associated with a serpentine belt of an internal combustion engine as depicted in an isometric drawing in  FIG. 1  so that the handle  10  may be manually engaged to pivot the pulley  20  mounted on idler arm  19  about idler arm pivot axis or shaft  21  to release the tension on belt  18  by movement of idler pulley  20  in opposition to the biasing force on the pulley  20  derived from the biased idler arm  19 . The handle  10  may have attached extensions such as an extension bar  22  so that the handle  10  and the extension bar  22  may be moved in unison to effect release of tension from an idler pulley  20  on a belt  18 .  
         [0028]      FIGS. 2 through 14  illustrate embodiments of the improved tool of the present invention. The embodiments each include a first actuation handle  30  and a second actuation handle  32 . In one embodiment handles  30 ,  32  are substantially identical and in use are arranged in an opposed relationship as depicted, for example, in  FIG. 2 . Each handle  30  and  32  includes a keyed opening  34  and  36 , respectively, at an inner end for receipt of a pivot pin  38 . Each handle  30  and  32  also includes a grip at its outer or opposite end for manual gripping, i.e. manual grips  39  and  40 , respectively. The handles  30  and  32  are made from flat bar stock and are shaped as depicted in the figures with a slight bend at about a mid-point to facilitate the manual use or gripping thereof.  
         [0029]     An extension bar or extension arm  42  includes a first idler pulley, keyed opening or passage  44  and a second distal end idler pulley, keyed opening  46 . Two openings  44 ,  46  are depicted and each opening  44 ,  46  is sized or keyed to a compatibly sized idler pulley shaft head, i.e. head  17  in  FIG. 1 . Thus, at least one keyed opening  44  or  46  is necessary, but two or more may be provided to accommodate pulley shaft heads of various size and configuration.  
         [0030]      FIGS. 2-9B  illustrate in further detail an embodiment of the invention. At the opposite end of the extension bar  42 , pin  38  is attached and retained in an opening  48  by means of a retention clip  50  and a separate retention clip  52  on the opposite side of extension bar  42  so that pin  38  will not slide laterally. The pin  38  extends transversely from the bar stock comprising the extension bar  42 . The extension bar pin  38  further includes a hexagonal, polygonal or keyed section  51  adjacent the extension bar  42  and an unkeyed center section  53  and an outer keyed section  54 . The actuation handles  30  and  32  may be engaged with the pin  38  by placement through the respective keyed openings  34  and  36 . A retention or retainer clip  56  retains the actuator handles  30  and  32  on the pin  38 .  
         [0031]     The first actuation handle  30  is designed to be engaged with and connected by means of keyed opening  34  to keyed section  51  of the pin  38 . The second handle  32  is designed to be engaged by means of keyed opening  36  with keyed section  54  of pin  38 . Each of the handles  30  and  32 , however, may be positioned in the unkeyed center section  53 . Thus, the unkeyed center section  53  has an axial dimension in the preferred embodiment which is slightly greater than the thickness of the two handles  30 ,  32  and a configuration which permits axial as well as rotational movement relative to pin  38 .  
         [0032]     In operation, one of the handles, for, example, handle  30 , is engaged with the keyed section  51  so that the extension arm  42 , which is affixed or keyed to the shaped end or head  17  of an idler pulley  41 , may be pushed or pulled to pivot idler pulley  41  mounted on cantilever arm  43  about the fulcrum  45  or pivot axis of the arm  43 . The second actuation handle  32  may then be moved from the unkeyed center section  53  and engaged with the keyed section  54  to effect further rotation of the extension bar  42  about the pivot  45 . Because the openings  34  and  36  form a regular polygon, for example, a hexagon shape and further because the keyed sections  51  and  54  comprise regular polygons, for example, a hexagon, the engagement of the handles  30  and  32  with the pin  38  may be easily effected by moving the handles axially or laterally  30 ,  32  into and out of engagement with the unkeyed section  53  and into and out of engagement with a keyed section  51  or  54 , as the case may be. The handles  30 ,  32  thus are manipulated out of phase or in steps with respect to each other. One handle  30  may thus move the idler pulley  41  a first distance about fulcrum  45  and be held while the second handle  32  is pivoted or rotated and then positioned on section  54  of pin  38  and manually moved to pivot the pulley  41  a further incremental distance about the axis  21  in  FIG. 1 . The handles  30 ,  32  are thus alternately engaged and disengaged and manipulated to effect release of pressure from pulley  41  on belt  18 . This procedure may be used during removal and installation of belt  18 .  
         [0033]     In sum, the extension bar  42  may be manipulated to thereby engage the idler pulley  41 , move the idler arm  43 , and thus reduce pulley tension on the serpentine belt  18  associated with an idler pulley  41 . The utilization of the two actuator arms  30  and  32  permits incremental rotational movement of the extension arm, bar or rod  42 .  
         [0034]     As previously described,  FIGS. 2-9A  are directed to one embodiment of the invention.  FIGS. 2-9A  are directed to a first embodiment of the invention wherein the keyed openings  34  and  36  associated with the handles  30  and  32 , respectively, are substantially identical and thus the handles  30  and  32  are substantially identical.  FIGS. 10-14  illustrate alternatives or additional embodiments wherein there is depicted a modification to the pin  38  associated with the extension arm  42  and further wherein the handles  30  and  32  are modified slightly and more particularly the keyed openings  34  and  36  are slightly rotated or out of phase with respect to one another. By making the keyed openings  34  and  36  in the embodiment of  FIGS. 10-12  slightly out of phase with one another, a mechanic is enabled to pivot or rotate the idler pulley and associated cantilever arm in smaller incremental steps thus providing greater flexibility in the utility of the tool.  
         [0035]     Referring therefore to  FIGS. 10-14 , it is first noted that  FIG. 10  depicts in a plan view a pin  38 A. The pin  38 A includes a center line axis  69 . The pin  38 A further includes an inner keyed section  51 A and an outer keyed section  54 A substantially identical to the keyed sections  51  and  54  of the pin  38 . A center, unkeyed section  53 A, however, has a distinct or different configuration. That is, the center or unkeyed section  53 A is partially keyed in the embodiment depicted in  FIG. 10 . Thus, a series of flats are provided, such as flat  66 , cut along the apex  68  of the keyed sections  51 A and  54 A. A secondary flat  70  connects a flat section  72  of keyed section  51 A with flat section  74  of keyed section  54 A. The axial extent of the flat  66  is substantially that of the unkeyed center section  53  of the pin  38 . Thus, the axial dimension  53 A is substantially the same as the axial dimension of the unkeyed cylindrical section  53  for the pin  38 .  
         [0036]     By providing the structure of  FIG. 10  for use in combination with the keyed openings, such as openings  34  and  36  of the handles  30  and  32 , those keyed openings  34 ,  36  are more easily fitted into the fully keyed sections  51 A and  54 A. The flats or lands, such as lands  70 , maintain the openings  34  and  36  properly axially aligned on the pin  38 A. In other words, the openings  34 ,  36  are maintained in co-axial alignment with keyed sections  51 A and  54 A. This arrangement facilitates axial movement of the handles  30 ,  32 .  FIG. 13  is a cross sectional view illustrating this feature. The shaded sections of  FIG. 13  comprise the portions thereof removed relative to the keyed sections.  
         [0037]      FIGS. 11 and 12  illustrate the alternative embodiment for the handles  30 A and  32 A.  FIG. 11 , for example, depicts the handle  30 A which is functionally equivalent to the handle  30 .  FIG. 12  illustrates handle  32 A which is functionally equivalent to the handle  32 . The difference between the handles of  FIGS. 11 and 12  with respect to the handles previously described is associated with the keyed openings  34 A and  36 A. First, the keyed openings  34 A  36 A comprise a regular duo decahedron. Also, the keyed openings  34 A and  36 A are slightly out of phase, one with respect to the other and the longitudinal axis of each handle  30 A,  32 A. Thus, as depicted in  FIG. 12 , the keyed opening  36 A is approximately 7.5° out of phase with the keyed opening  34 A of  FIG. 11 . As a result, shorter incremental movement may be effected utilizing the handles  30 A and  32 A as described.  
         [0038]     Various other modifications may be made to the described tool. For example, the openings which are keyed in the handles  30  and  30 A,  32  and  32 A, may be sized and shaped to accommodate various rotational amounts of movement through interaction with the respective pins  38  and  38 A.  
         [0039]     For example, as shown in  FIG. 14 , the handle  30  may include a keyed opening  34 B offset by 3.75°. The same handle  30  may then be positioned on pin  38  by reversal thereof to effectively provide a 7.5° difference in the phase mounting on pin  38 . In this manner, a single part may be manufactured to achieve the desired rotational phase difference. The outer end of the handle  30  in  FIG. 14  may be bent or angled in opposite directions as shown in  FIG. 2 .  
         [0040]     In the drawings, there is depicted a 12-sided keyed opening  34  and  36 ,  34 A and  36 A. However, different keying arrangements may be utilized. As previously mentioned, the keyed openings associated with the extension arm, extension bar  42  may also be altered to accommodate various needs. Thus, the tool as described may be used not only with a serpentine belt idler pulley, but other uses requiring incremental movement of such items in a restricted space may be effected utilizing the tool of the invention. Additionally, the keyed sections of the pin  38  may be offset relative to one another to accomplish the object of the out of phase relationship associated with the handles  32 A and  30 A described above. Further, the number of flats associated with the center section  53 A may be varied. Such variance may, for example, may range from 2-12 or more sides. At least two of the flats associated with the center section  53 A are coplanar with the facets or faces of the keyed sections  51 A,  54 A. Also, the pin  38  may be attached so that it projects through the arm  42  with a keyed section  51  or  54  on each side thereof and with a rotational section  53  on each side thereof. The invention is therefore to be limited only by the following claims and equivalents thereof.