Abstract:
A cover positioned over one or more fasteners that attaches a component to a shaft. The cover is positioned over the one or more fasteners to prevent interaction between the one or more fasteners and a hydraulic fluid as the component moves through the hydraulic fluid.

Description:
FIELD 
       [0001]    The present relates to a cover to reduce spin loss of a bolted component. 
       BACKGROUND 
       [0002]    The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
         [0003]    A typical motor vehicle transmission includes numerous components that interact with each other during the operation of the transmission. For example, a transmission generally includes multiple gears that selectively engage with each other to achieve various desired speed ratios. Some of these gears may be attached to a rotatable shaft with an attachment mechanism, such as, for example, a set of bolts. The gears are at least partially immersed in a hydraulic fluid that lubricates the gears and dissipates heat during the operation of the transmission. The rotation of the gears, however, results in the bolts to interact with the hydraulic fluid as the gears rotate. This interaction creates drag, resulting in spin loss, that is, wasted energy created by the drag. 
         [0004]    While current transmissions achieve their intended purpose, the need for new and improved transmission configurations which exhibit improved performance and improved efficiency remains constant. 
       SUMMARY 
       [0005]    The present invention provides an apparatus positioned over an attachment mechanism that attaches a component to a shaft. 
         [0006]    In one aspect, the apparatus is a cover that can have a generally circular shape, and the attachment mechanism is one or more fasteners. The cover is positioned over the one or more fasteners to prevent interaction between the one or more fasteners and a hydraulic fluid as the component moves through the hydraulic fluid. The apparatus may be further characterized by one or any combination of the features described herein, such as, for example: the cover has an annular shape; the cover is made of a plastic or a metal; the cover is attached to the rotating component with an adhesive; the cover is attached to the rotating component with by weld or press-fitting the cover to the component; the component is one or more gears that may intermesh with a second gear; and the hydraulic fluid is a lubricant. 
         [0007]    In another aspect, a transmission includes a shaft, one or more gears attached to the shaft with a plurality of fasteners, and a cover positioned over the plurality of fasteners to prevent interaction between the plurality of fasteners and a hydraulic fluid as the one or more gears rotates through the hydraulic fluid. 
         [0008]    Further features, advantages, and areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0009]    The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. In the drawings: 
           [0010]      FIG. 1A  is front view of a cover in use with a bolted gear in accordance with the principles of the present invention; 
           [0011]      FIG. 1B  is a side view of the cover shown in  FIG. 1A ; and 
           [0012]      FIG. 2  is a front view of an alternative cover in accordance with the principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. 
         [0014]    Referring now to  FIGS. 1A and 1B , a portion of a transmission  10  with a cover  12  embodying the principles of the present invention is illustrated therein. The transmission portion  10  includes a first gear  14  that intermeshes with a second gear  16 . The first gear  14  and the second gear  16  are positioned in a housing  11  partially filled with a hydraulic fluid  13 , such as, for example a lubricant or oil. In the arrangement shown, the first gear  14  is bolted to a shaft  20  with an attachment mechanism such as a set of bolts  18 , or any other suitable fasteners, for example, rivets that may result in an irregular surface. The cover  12  is secured to the first gear  14  such that the set of bolts  18  are enclosed within the cover  12 . The cover  12  can be secured or attached to the first gear  14  by an adhesive or by welding or press-fitting the cover  12  to the first gear  14 , or by any other suitable mechanism. The cover  12  can be made from a plastic, metal or any other suitable material. 
         [0015]    As shown in  FIG. 1A , the cover  12  has an annular shape with an opening  22 . When the transmission portion  10  is in use, the first gear  14  is partially immersed in the hydraulic fluid  13  so that as the first gear  14  selectively rotates about the shaft  20 , the first gear  14  rotates through the hydraulic fluid  13 . If the cover  12  is not attached to the first gear  14 , each bolt of the set of bolts  18  periodically passes through the hydraulic fluid  13 . The interaction between the bolts  18  and the hydraulic fluid  13  as the first gear  14  rotates results in splashing of the hydraulic fluid  13 , thereby creating spin loss of energy of the first gear  14  and the second gear  16 . Placement of the cover  12  over the bolts  18  eliminates the interaction of the bolts  18  with the hydraulic fluid  13 . Hence as the first gear  14  rotates about the shaft  20  through the hydraulic fluid  13 , the cover  12  prevents splashing between the bolts  18  and the hydraulic fluid  13 . As such, the use of the cover  12  reduces or lowers spin loss associated with the rotation of the first gear  14  through the hydraulic fluid  13 . 
         [0016]    In another arrangement, rather than an annular ring placed over the set of bolts  18 , each bolt is covered individually. In yet another arrangement shown in  FIG. 2 , a transmission portion  110  includes a cover  112  that fully covers the set of bolts  18  as well as the terminal end of the shaft  20 . Specifically, the cover  112  does not include the open interior region  22  associated with previously describe cover  12 . Again, the cover  112  eliminates the interaction of the bolts  18  with the hydraulic fluid  13 . Hence as the first gear  14  rotates about the shaft  20  through the hydraulic fluid  13 , the cover  112  prevents splashing between the bolts  18  and the hydraulic fluid  13 . As such, the use of the cover  112  reduces or lowers spin loss associated with the rotation of the first gear  14  through the hydraulic fluid  13 . 
         [0017]    The description of the invention is merely exemplary in nature and variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.