Patent Document

FIELD 
       [0001]    The present disclosure relates to a bracket assembly suitable for mounting structures to one another and for absorbing vibration and movement therebetween. More specifically, the present disclosure relates to a tunable hybrid bracket assembly for mounting a fan to a vehicle engine. 
       BACKGROUND 
       [0002]    The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
         [0003]    In operation, an engine transforms heat energy into mechanical energy. However, the heat energy is not completely consumed. Unused heat is retained by the engine and over time can cause engine temperature to increase to an undesirable level. A cooling system is used to remove the excess heat from the engine and maintain an ideal operating temperature. When at ideal temperature, the engine performs more efficiently, emissions are lower and component wear is minimized. 
         [0004]    The cooling system employs various methods for achieving and maintaining the ideal temperature. Typically, a liquid coolant flows through pipes and passageways in the engine. As the coolant flows through the pipes and passageways, it absorbs the excess heat and transfers it to a radiator. The radiator has fins which conduct heat from the coolant flowing within the radiator to the surrounding air. When airflow is satisfactory, the heated air will be removed from the system. However, in unsatisfactory conditions, such as, stationary or slow-moving airflow conditions (i.e. when the vehicle is stopped or in heavy traffic), a fan may be operated to generate an additional airflow. The fan may be turned on and off at specific temperatures to maintain a desired system temperature for increased engine efficiency and can also be active during air conditioner and defroster activity. 
         [0005]    In compact engine compartments such as, vehicle engine compartments, the fan may be mounted directly to the vehicle engine. Engine vibration can damage electrical components in the fan housing. 
       SUMMARY 
       [0006]    Accordingly, the design of the present disclosure includes a motor vehicle engine having a cooling fan for removing excess heat from the vehicle engine mounted together by means of a tunable bracket assembly. The bracket assembly includes a bracket member, a washer and a bushing. The bracket member has an angled configuration for attenuating vehicular noise, vibration and harshness and the washer integrally formed therewith. The bushing is press fit in the bracket member for attenuated attachment to the vehicle engine. 
         [0007]    Further 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 
         [0008]    The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
           [0009]      FIG. 1  is a schematic view of an exemplary vehicle engine compartment in accordance with the principles of the present teachings; 
           [0010]      FIG. 2  is a perspective view of a cooling fan mounted to an engine by means of a tunable hybrid bracket assembly in accordance with the principles of the present teachings; 
           [0011]      FIG. 3  is a perspective view of the tunable hybrid bracket assembly in accordance with the principles of the present teachings; 
           [0012]      FIG. 4  is an exploded view of the tunable hybrid bracket assembly of  FIG. 3  in accordance with the principles of the present teachings; 
           [0013]      FIG. 4A  is a top plan view of a key-slotted washer of the tunable hybrid bracket assembly in accordance with the principles of the present teachings; 
           [0014]      FIG. 4B  is a top plan view of a circular washer of the tunable hybrid bracket assembly in accordance with the principles of the present teachings; and 
           [0015]      FIG. 5  is a cross-sectional view of the tunable hybrid bracket assembly taken along line  5 - 5  of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. 
         [0017]      FIG. 1  depicts a typical automotive vehicle  10 . The vehicle  10  includes an underhood or engine compartment  12  for packaging vehicular componentry. While  FIG. 1  depicts an automotive vehicle, the present teachings may also be applied to other configurations such as, test stands, boats, aircraft and other industrial applications where a mounting bracket assembly can be utilized to isolate and/or absorb vibrations between two structures. 
         [0018]    The engine compartment  12  typically includes an array of parts such as an engine  14 , an air induction system (not shown) and a cooling system  18  to name but a few. The cooling system  18  of the vehicle  10  may be used to remove heat from the engine  14  by means of various devices including coolant, a radiator, a cooling fan, etc. The coolant moves through pipes and passageways (not shown) in the engine  14 , the radiator  20  uses fins to disperse heat, and a cooling fan  22  removes stagnant heat from the system. Each of these devices may be used singly or may be combined to obtain optimal system performance. 
         [0019]    Referring now to  FIG. 2 , a tunable hybrid bracket assembly  24 , which resists torque and isolates vibration, may be utilized to mount the cooling fan  22  to the engine  14 . The tunable hybrid bracket assembly  24  includes a bracket member  26 , a key-slotted washer  28  and a bushing  30 , as shown in  FIG. 3 . The bracket member  26  is generally molded from a thermoplastic or thermoset material such as phenolic, polyester or vinylester. Alternatively, the bracket member  26  may be made of a metal such as steel, aluminum or magnesium, or a combination of metal and plastic material. The bracket member material may be chosen for characteristics including damping, stiffness and geometry, and is tunable from the resonant frequencies of engines or other sources. 
         [0020]    With reference to  FIGS. 3 and 4 , the bracket member  26  is discussed in further detail. The bracket member  26  may be an elongated body having a first end  34  for attachment to the engine  14 , a second end  36  for attachment to the cooling fan  22  and an intermediate portion  38  therebetween. The first end  34  may be bent at an angle, α 2 , from the intermediate portion  38 . The angle, α 2 , may be between 90 degrees and 180 degrees, and as shown approximately 120 degrees. The second end  36  may be bent at an angle, α 1 , from the intermediate portion  38 . The angle, α 1 , may be between 90 degrees and 180 degrees, and as shown approximately 140 degrees. The first end  34  of the bracket member  26  may include a flange portion  40  and the second end  36  of the bracket member  26  may include a tubular portion  42 . The tubular portion  42  may have an axis, A, through the bushing  30 . The axis, A, and the second end  36  may have an inclusive angle, α 4 , between 0 degrees and 90 degrees and, as shown approximately 30 degrees. The intermediate portion  38  of the bracket member  26  may include a first thru hole  44  for receivably attaching a wiring harness  46  (as shown in  FIG. 2 ). After attachment, the wiring harness  46  may behave as a mass to provide an additional element of mass damping for the system. 
         [0021]    The flange portion  40  of the first end  34  may contain a key-slotted hole  48  for receiving the key-slotted washer  28  as shown in  FIG. 4A . The key-slotted washer  28  may be insert molded in the bracket member  26  or may be incorporated post-molding. Alternatively as depicted in  FIG. 4B , a circular washer  52  may be molded within the bracket member  26  during forming or incorporated post-molding. The bracket member  26  and circular washer  52  may then be machined to remove a portion of material which forms a key slot  54  for receivably attaching the engine  14  (depicted by dotted lines in the figure). The washer  28 ,  52  may be made of a metal such as steel, aluminum or magnesium; a plastic such as an elastomer, thermoplastic or thermoset; or a combination of metal and plastic material. The washer material may be chosen for characteristics including damping, stiffness and geometry, and is tunable for the resonant frequencies of engines or other sources. 
         [0022]    Referring again to  FIGS. 3 and 4 , the bracket member  26  may form a second flange portion  56 , adjacent to the first end  34  at an inclusive angle, α 3 . Angle, α 3 , may be between 90 degrees and 180 degrees, and as shown approximately 115 degrees. This second flange portion  56  may contain a second thru hole  58  for receivably attaching the wiring harness  46  as shown in  FIG. 2 . As previously noted, the wiring harness  46  may behave as a mass to provide an additional element of mass damping for the system. 
         [0023]    The tubular portion  42  may receive the bushing  30 . The bushing  30  is inserted into the tubular portion  42  until the bottom portion  30   a  extends axially above the top surface  60  of the tubular portion  42 . In order to provide for ease in assembly, a highly compliant material, such as a foamed elastomeric material or natural rubber may be used for the bushing  30 . Enhanced acoustical properties, such as those found in microcellular polyurethane (MCU) may also be desired. While the exemplary embodiment may utilize an MCU material because of its special tuning range for low dynamic stiffness, the foamed elastomeric material may also be a fluorocarbon, highly saturated nitrile (HNBR), methyl acrylate acid polymer, silicone, EPDM, Neoprene®, thermoset elastomer, thermoplastic elastomer, Santoprene®, Geolast®, Sarlink®, Hytrel®, or any other elastomeric foamed material suitable for the application. 
         [0024]    Referring now to  FIG. 5 , a cross-sectional view of the bushing  30  after insertion is depicted. The bushing  30  is depicted as having a stepped cylindrical cross-section, however, the bushing  30  may also have any other suitable shape, including, for example, a full cylindrical shape. 
         [0025]    The description of the invention is merely exemplary in nature and, thus, variations that do no 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.

Technology Category: f