Abstract:
An idler assembly includes a cam, an idler pulley, a baseplate, an idler pulley bracket, and a belt. The cam is pivotally mounted to an idler pulley bracket, the cam may pivot between a first position and a second position via a first pivot. The idler pulley is mounted to a baseplate. The baseplate is pivotally mounted to an idler pulley bracket. The baseplate may therefore pivot between a first position and a second position relative to the idler pulley bracket. The belt may be easily mounted on the idler pulley when the baseplate and cam are in the second position. The belt is in tension when the baseplate and cam are moved from the second position to the first position.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure concerns engine components, and more particularly, the serpentine belt and pulley system of an engine. 
       INTRODUCTION 
       [0002]    In automotive industries, belts are used to drive various components of a vehicle. Examples of such components include power steering, alternator, water pump, AC compressor and the like. Typically, the belts transfer power from an engine of the vehicle to these components for driving them. These days, instead of employing belts individually for each of the components, a single belt is employed for driving all such components in the vehicle. Such a belt, conventionally known as a serpentine belt, routes around various drive and idler pulleys associated with various components of the vehicle. 
         [0003]    With consistent use thereof, the serpentine belt (hereinafter referred to as “belt”) undergoes wear and tear over a period of time. Consequently, the belt may slip from one or more of the pulleys and/or idlers associated with the various components of the vehicle. Slipping between the belt and pulleys/idlers leads to increase in load on the engine, more power consumption or failure in the power transmission to the components of the vehicle. Accordingly, the belt requires maintenance or replacement from time to time. During replacement or maintenance thereof, the belt may be installed, removed, routed or adjusted on/from the pulleys and gears. 
         [0004]    While installing, removing, routing, or adjusting the belt, it is required to handle the belt carefully due to various reasons. One of the reasons is availability of very less clearance while accessing the pulleys and idlers of the engine under a hood of the vehicle. Due to this, it may be difficult to reach the belt for handling it. 
         [0005]    Typically, a front-wheel-drive vehicle with a transversely mounted engine provides limited access to the belt, thereby necessitating lifting of the front wheel of the vehicle from the ground for accessing the belt. Further, in some vehicles, a splash shield needs to be removed for accessing the front portion of the engine for handling the belt. Such an activity of removing the splash shield for accessing of the belt is cumbersome for an individual handling the belt. Furthermore, in some other cases, handling of the belt is much more difficult when the engine is hot. Due to these above mentioned reasons, just accessing the belt can be a time consuming and unpleasant experience for any individual such as an automotive specialist. 
         [0006]    Currently, a rod or a screwdriver may be used to adjust the belt on the pulley. However, the belt may be slipped off from the rod or the screwdriver while being adjusted. This may require additional effort to first adjust the belt on the rod or the screwdriver and thereafter, to adjust the belt on the pulleys and/or idlers. Accordingly, handling the belt by using the rod or the screwdriver may be time consuming and tiresome for an individual handling the belt. 
       SUMMARY OF THE INVENTION 
       [0007]    The present disclosure provides an idler assembly and method for easily installing a belt onto an idler and drive pulley system of an engine where the packaging space is very limited. 
         [0008]    The idler assembly includes a cam, an idler pulley, a baseplate, an idler pulley bracket, and a belt. The cam is pivotally mounted to an idler pulley bracket, the cam may pivot between a first position and a second position via a first pivot. The first pivot may include a force balancing biasing means to urge the cam to rotate in a clockwise direction. The biasing means for the first pivot or second pivot may be an arc spring which is disposed within a recess of the idler pulley bracket. An alternative, non-limiting example of another biasing means may be a torsion spring which is disposed at the first pivot and/or second pivot. 
         [0009]    The idler pulley is mounted to a baseplate. The baseplate is pivotally mounted to an idler pulley bracket. Similar to the first pivot, the second pivot may include a force balancing biasing means to urge the baseplate to rotate in a clockwise direction. As shown in  FIG. 6 , the biasing means for the second pivot may be an arc spring which is disposed within a recess of the idler pulley bracket. An alternative, non-limiting example of another biasing means may be a torsion spring which is disposed at the first pivot and/or second pivot. 
         [0010]    The idler pulley bracket is affixed to the cylinder block, the generator, and/or other accessory or engine components. Given that the baseplate is pivotally mounted to the idler pulley bracket, the baseplate may therefore pivot between a first position and a second position. The belt may be easily mounted on the idler pulley when the baseplate and cam are in the second position given that the belt is no longer in tension. 
         [0011]    The present disclosure also includes a method for servicing an idler assembly  10 . The method includes the steps of pivoting a cam from a first position to a second position and then pivoting a baseplate and an idler pulley from a first position to a second position. While the cam and the baseplate are in their respective second positions, a user may easily remove the belt which is no longer in tension. Furthermore, while the cam and the baseplate are in their respective second positions, a user may install a second belt onto the idler assembly. Once the new or repaired belt is mounted onto the various engine drive, driven, and/or idler pulleys, the pivoting cam may be moved from the second position back to the first position while pivoting the baseplate and the idler pulley from the second position back to the first position. The cam and baseplate may therefore be in an engaged position where they abut each other in the first position and a user may secure a final bolt to the baseplate to complete assembly and to prevent movement of the baseplate  14 . It is further understood that the cam and the baseplate may each include an indicator  80 ,  80 ′ where the marks for the indicators  80 ,  80 ′ (shown in  FIG. 4 ) line up and a user may determine as to whether the cam and the baseplate are adequately engaged. 
         [0012]    The invention and its particular features and advantages will become more apparent from the following detailed description considered with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    These and other features and advantages of the present disclosure will be apparent from the following detailed description of preferred embodiments, and best mode, appended claims, and accompanying drawings in which: 
           [0014]      FIG. 1  is a front view of an engine with the engine pulley of the present disclosure. 
           [0015]      FIG. 2  is a front view of the present disclosure with the engine pulley system in a first position. 
           [0016]      FIG. 3  is a front view of the present disclosure with the engine pulley system in a second position. 
           [0017]      FIG. 4  is a front view of the present disclosure showing the cam and baseplate in both the first position and the second position. 
           [0018]      FIG. 5  is a cross sectional view of first pivot showing the cam feature in the idler pulley bracket. 
           [0019]      FIG. 6  is a front view of a recess in the baseplate bracket along with the arc spring for the recess. 
       
    
    
       [0020]    Like reference numerals refer to like parts throughout the description of several views of the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    The exemplary embodiments described herein provide detail for illustrative purposes, and are subject to many variations in composition, structure, and design. It should be emphasized, however, that the present disclosure is not limited to a particular tool for handling the belt  22 , as shown and described. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present disclosure. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. 
         [0022]    The terms “first,” “second,” and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another, and, the terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. 
         [0023]    The present disclosure provides an idler assembly  10  and method which reduces manufacturing costs, assembly  10  time to install, service and/or remove a belt  22 . The new idler assembly  10  arrangement addresses the challenges associated with working in the limited packaging space of the idler assembly  10  given the compact nature of the design. 
         [0024]    With reference to  FIG. 2 , a front view of the idler assembly  10  is shown in a first position  48  where the belt  22  is shown in the installed position. As shown, the idler assembly  10  uses an idler pulley  20  which is mounted to a pivoting baseplate  14 . The idler pulley  20  rotates about an axis which is affixed to the baseplate. The idler pulley  20  is part of a vehicle&#39;s belt system that helps regulate how the belts run from the crankshaft (via crankshaft pulley  90  in  FIG. 2 ) to generate movement in other parts such as generator  32  and other engine accessories. Belt  22  rests on the generator pulley  34 , idler pulley and the crankshaft pulley among other things. These engine belts are often called “serpentine belts”  22  when they run across various pulleys, and they often run the air conditioning compressor, power steering pump, and alternator of a vehicle. 
         [0025]    As shown in  FIGS. 2 and 3 , the idler pulley  20  may be rotated so that it moves between a first position  48  (shown in  FIG. 2 ) to a second position  50  (shown in  FIG. 3 ) to allow for the belt  22  to be installed when the idler pulley is in the second position  50 . To move from the first position  48  to the second position  50 , the cam  12  is turned out of the way and up via the first pivot  16 , thereby allowing idler and the baseplate  14  to also rotate up about the second pivot  18 . Similar to the first pivot  16 , the second pivot  18  may also include a force balancing biasing means, such as a torsion spring  28 , which will urge the second pivot  18  to rotate in a clockwise direction as shown in  FIG. 4 . When the baseplate  14  is rotated up, there is less tension on the belt  22  thereby making it much easier for a user to remove the belt  22  from the pulley and engine. 
         [0026]    Another belt  22  (new or repaired) may be installed when the baseplate  14  and cam  12  are in the second position  50  as shown in  FIG. 3  given that the vertical distance changes from Y  36  (shown as  20  in  FIG. 2 ) to Y′  38  (shown as  22  in  FIG. 3 ). The vertical distance of is the vertical distance between the idler pulley  20  and the generator pulley  34  when the belt  22  is in tension. As illustrated, the vertical distance Y between the generator pulley  34  and the idler pulley  20  is decreased when the components are in the second position  50  thereby allowing the belt  22  to have a looser fit around the idler pulley  20  and making it easier to remove/install/service the belt  22 . When the idler assembly  10  is in the second position  50 , the stretchy belt  22  can be installed without tension. After a new or repaired belt  22  is installed, the cam  12  is rotated against the baseplate  14  so that the cam  12  moves from the cam&#39;s second position  50  back to the first position  48 . The baseplate  14  and the idler pulley  20  then rotate about second pivot  18 , moving the idler pulley  20  back into the first position  48  where the belt  22  is in tension and installed. 
         [0027]    With reference to  FIG. 4 , the cam  12  may be manually rotated between the first and second positions  48 ,  50 . Cam  12 ′ is in the second position while cam  12  is in the first position. Similarly baseplate  14 ′ is in the second position while baseplate  14  is in the first position. An extension from a tool may fit into a cam aperture  70  or recess in the cam  12  to rotate the cam  12  counter clockwise. The idler pulley  20  and the base plate may rotate down from the first position as baseplate  14 ′ to the second position as baseplate  14  about the second pivot  18  having torsion spring  28  thereby applying tension to the belt  22 . The force vector  59  of the belt  22  under tension holds the cam  12  in the engaged position where the first engagement edge  44  of the cam  12  is fully abutted against the second, engagement edge  46  of the baseplate  14 . Moreover, as indicated, the first and second pivots  16 ,  18  may each include a force balancing biasing means  26  such as, but not limited to a torsion spring  28  such that the cam  12  is urged against the baseplate  14  via the force balancing biasing means  26  at the first pivot  16 , and the baseplate  14  is urged toward the cam  12  via the force balancing biasing means  26  at the second pivot  18 . It is understood, that the force balancing means  26  at the second pivot  18  may also react against the pulley hub load. Accordingly, the load from the belt  22  and optionally together with the force balancing biasing means ensures that the baseplate  14  is fully abutting the cam  12 . While the components are maintained in the engaged position, a user may secure a final bolt  24  to the baseplate  14  and the idler pulley bracket  21 . The final bolt  24  affixes the baseplate  14  to the idler pulley bracket  21  such that the baseplate  14  is in the first position  48  (or engaged position). 
         [0028]    Accordingly, as shown, the cam  12  allows the idler pulley  20  and baseplate  14  to rotate about the second pivot  18  in a compact swing radius down into the installed position given that the outer edge  72  of the cam  12  slides along the second engagement edge  46  of the baseplate  14  thereby causing the baseplate  14  to rotate downward in a clockwise manner. As shown in  FIGS. 2 and 3 , the cam  12  defines a first engagement edge  44  while the baseplate  14  defines a second engagement edge  46 . When the cam  12  is fully rotated to engage with the baseplate  14  to apply tension to the belt  22  in the second position  50 , the first engagement edge  44  of the cam  12  abuts the second engagement edge  46  of the baseplate  14 . Again, the vector force  59  applied to the baseplate  14  due to the belt  22  being in tension allows these rotating components to remain engaged and stationary so that a worker does not need to hold the components in place while securing the final bolt  24 . 
         [0029]    With reference to  FIG. 5 , the cam  12  may be designed such that a portion of the cam  12  is in the form of a protrusion  56  which fits within an opening  64  of the idler pulley bracket  21 . The pivot pin  54  may be disposed within a cam bore  62  defined in the cam protrusion  56 . As shown in  FIG. 5 , a sleeve  58  may be disposed between pivot pin  54  and the cam  12 /idler pulley bracket  21 . 
         [0030]    While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the disclosure as set forth in the appended claims and the legal equivalents thereof.