Abstract:
The present invention is a throttle body assembly which is adaptable for both gasoline and diesel applications, and may also be used for applications to meter fluid, such as for a water cooling valve. The throttle body assembly includes at least one bearing assembly and at least one seal which is used to configure the bearing assembly to withstand a high-pressure environment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 62/280,268 filed Jan. 19, 2016. The disclosure of the above application is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates generally to a bearing and seal combination used for an electronic throttle body assembly to allow the electronic throttle body assembly to operate at high pressure without damaging the bearings. 
       BACKGROUND OF THE INVENTION 
       [0003]    Throttle body assemblies are generally known, and are a type of valve assembly used for controlling the amount of air flow into the engine during vehicle operation. The throttle body assemblies typically include a valve plate mounted on a shaft which is rotated to control air flow. There is also some type of bushing or bearing which supports the shaft. The throttle body assembly is located in the engine compartment, and is exposed to a harsh environment. The bearings or bushing may be exposed to debris that may be in the air flowing through the valve assembly, acid from the vehicle fuel, and may be exposed to high pressure and high air flow rate. Requirements are such that throttle body assemblies are adaptable for gasoline and diesel applications, as well as have the capability to withstand exposure to a harsh environment. If bearings are used, the bearings are typically needle bearings, because needle bearings and bushings are able to withstand the pressure in the harsh environment. 
         [0004]    Ball bearings are considered more desirable for use in these applications since ball bearings offer the advantages of greater durability, assembly, and reduced friction. However, ball bearings typically cannot withstand these harsh environments, primarily because ball bearings are not suitable for operation when exposed to higher air pressure and vacuum, such as environments where the pressure or vacuum is greater than 1.0 bar. The debris and the acid may cause degradation of the bushings or bearings. 
         [0005]    Accordingly, there exists a need for a throttle body or valve assembly which is able to incorporate the use of ball bearings which are configured to withstand a harsh environment, such as those where the pressure is 1.0 bar or greater. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is a throttle body assembly which is adaptable for both gasoline and diesel applications, and may also be used for applications to meter fluid, such as for a water cooling valve. The throttle body assembly includes at least one bearing assembly and a seal which are used to configure the bearing assembly to withstand a high-pressure environment. 
         [0007]    In accordance with an embodiment, the present invention is a valve assembly, including a housing, a central port formed as part of the housing, an aperture formed as part of the housing, and a shaft extending through the aperture such that the shaft extends through the central port. A valve plate is mounted on the shaft such that the valve plate is disposed in the central port. There is also a bore formed as part of the housing, the shaft at least partially extending through the bore. At least one seal is located in the bore such that the seal surrounds the shaft, and at least one bearing assembly is mounted on the shaft and located in the bore such that the bearing is adjacent the seal. As the shaft is rotated to change the position of the valve plate and air flow through the central port, the seal prevents the bearing from being damaged due to exposure to high pressure from the air flow. In one embodiment, the seal prevents the bearing from being damaged due to exposure to pressures greater than or equal to 1.0 bar. 
         [0008]    In one embodiment, the seal is located between the bearing assembly and the central port. In another embodiment, the bearing assembly is located between the seal and the central port. 
         [0009]    In one embodiment, the seal has an X-cross section which includes a least one inner flange portion and at least on outer flange portion, where the inner flange portion is in contact with the shaft, and the outer flange portion is in contact with the boss. 
         [0010]    In another embodiment, the seal includes a base portion, and at least one flange portion integrally formed with the base portion, where the base portion is in contact with the bore, and the flange portion is in contact with the shaft. 
         [0011]    In yet another embodiment, the seal includes an outer base portion, and at least one inner lip portion is integrally formed with the outer base portion, such that the outer base portion is in contact with the bore, and the inner lip portion is in contact with the shaft. 
         [0012]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0014]      FIG. 1  is a perspective view of a housing of the throttle body assembly, according to embodiments of the present invention; 
           [0015]      FIG. 2  is an exploded view of a throttle body assembly of an embodiment, according to embodiments of the present invention; 
           [0016]      FIG. 3  is a sectional side view of a bearing assembly disposed in a bore of a housing, according to embodiments of the present invention; 
           [0017]      FIG. 4  is a sectional side view of a bearing assembly and an embodiment of a seal disposed in a bore of a housing, according to embodiments of the present invention; 
           [0018]      FIG. 5  is a sectional side view of a bearing assembly and another embodiment of a seal disposed in a bore of a housing, according to embodiments of the present invention; 
           [0019]      FIG. 6  is a sectional side view of a bearing assembly and yet another embodiment of a seal disposed in a bore of a housing, according to embodiments of the present invention; 
           [0020]      FIG. 7  is a sectional side view of a bearing assembly and still another embodiment of a seal disposed in a bore of a housing, according to embodiments of the present invention; 
           [0021]      FIG. 8  is a sectional side view of a bearing assembly and still another embodiment of a seal disposed in a bore of a housing, according to embodiments of the present invention; and 
           [0022]      FIG. 9  is a sectional side view of a bearing assembly and yet another embodiment of a seal disposed in a bore of a housing, according to embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0023]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
         [0024]    A throttle control assembly according to the present invention is shown in the Figures generally at  10 . The assembly  10  includes a housing  12 , and formed as part of the housing  12  is a central port  14 , through which air passes during operation of the assembly  10 . Extending through in the central port  14  is a shaft  16 , which is rotatable. The shaft  16  includes a slot  18 , and disposed in the slot  18  is a valve member, which in this embodiment is a valve plate  20 . The valve plate  20  includes two apertures  22 , which are in alignment with two threaded apertures  24  formed as part of the shaft  16 . Also connecting the plate  20  to the shaft  16  is a fastener, which in this embodiment is a threaded screw  26 , which is inserted through the apertures  22  of the plate  20  and the threaded apertures  24  of the shaft  16 , securing the valve plate  20  to the shaft  16 . 
         [0025]    The shaft  16  is partially disposed in an aperture  28   a  formed as part of a first boss  52   a,  and the first boss  52   a  is formed as part of the housing  12 . The central port  14  also includes a side wall  14   a,  which also forms part of the first boss  52   a,  and the aperture  28   a  is formed as part of the boss  52   a.  A first bearing assembly  30   a  and a second bearing assembly  30   b  support the shaft  16 , and allow for the shaft  16  to rotate relative to the housing  12 . The first bearing assembly  30   a  is located in the boss  52   a  and held in place in the boss  52   a  by a plug  32 . The second bearing assembly  30   b  is located in a second boss  52   b,  and is maintained in the boss  52   b  by a C-washer  34  located in a groove  50  formed as part of the shaft  16 . There is a second aperture  28   b  formed as part of the side wall  14   a  such that the second aperture  28   b  is formed as part of the second boss  52   b.  The second bearing assembly  30   b  is located between the C-washer  34  and the end of the shaft  16 , and is located inside and supported by the boss  52   b  formed as part of the housing  12 . 
         [0026]    The housing  12  also includes a cavity, shown generally at  36 , and disposed in the cavity  36  is an actuator, which in this embodiment is an electric motor  38 , held in place by two motor screws  40 . Attached to the shaft of the motor  38  is a first gear, or pinion gear  42 . The pinion gear  42  is in mesh with a second gear, or intermediate gear  44 . The intermediate gear  44  is mounted on an intermediate shaft  46 , and the intermediate shaft  46  partially extends into an aperture  48  formed as part of the housing  12 . Also formed as part of the intermediate gear  44  is a middle gear  54 , which is smaller in diameter compared to the intermediate gear  44 . The middle gear  54  is in mesh with a sector gear  58 . 
         [0027]    Mounted on and surrounding the outside of the boss  52  is a lower bushing  60 , and mounted on the lower bushing  60  is a biasable member  62 , which in this embodiment is a return spring  62 , having two coil portions. The return spring surrounds the lower bushing  60 , and there is an intermediate bushing  66  disposed between the coil portions of the return spring  62 . The intermediate bushing  66  includes a slit portion  68  which allows the intermediate bushing  66  to partially deflect without breaking, such that the coil portions may be made together from a single continuous wire, and the intermediate bushing  66  may be installed between the coil portions. 
         [0028]    The sector gear  58  is mounted on one of the coil portions, and one end of the return spring  62  is in contact with a first pin  74  functioning as a first spring stop, and a second end of the return spring  62  in contact with a second pin  76  functioning as a second spring stop. Each of the pins  74 , 76  are partially disposed in corresponding apertures  78  formed as part of the housing  12 . 
         [0029]    Connected to the housing  12  is a cover  80 , and disposed between the cover  80  and the housing  12  is a seal  82  which surrounds an outer lip  84  formed as part of the housing  12 . The cover  80  is connected to the housing  12  using a plurality of clips  86 . There is also a secondary cover  88 , which is attached to the cover  80 . Once the cover  80  is attached to the housing  12 , the terminals for the motor  38  can be viewed through an opening in the cover  80 . Once it is determined that the terminals of the motor  38  are in contact with the terminals formed as part of the cover  80 , the secondary cover  88  is attached to the cover  80 . 
         [0030]    The cover  80  also includes a connector  90  which is in electrical communication with the motor  38 , such that the connector  90  is able to be connected to a source of power. Integrally formed with the cover  80  is a lead frame, which places the connector  90  in electrical communication with a sensor (not shown). 
         [0031]    An enlarged sectional view of a portion of the housing  12  is shown in  FIG. 3 , which includes the boss  52   b,  and the second bearing assembly  30   b.  Although the second bearing assembly  30   b  is shown, it is within the scope of the invention that the various aspects of the invention apply to the first bearing assembly  30   a  as well. The bearing assemblies  30   a , 30   b  in this embodiment are ball bearing assemblies. The bearing assembly  30   b  shown in  FIG. 3  includes an inner race  92  in contact with the shaft  16 , and an outer race  94  in contact with the boss  52   b.  Disposed between the inner race  92  and the outer race  94  is a bearing member  94   a,  which in this embodiment is a ball. There are also several outer seal surfaces  96 , one of the outer seal surfaces  96   a  may be part of the shaft  16 , another of the outer seal surfaces  96   b  is part of the boss  52   b,  one of the surfaces  96   c  may be part of the inner race  92 , and another of the outer seal surfaces  96   d  may be part of the outer race  94 . There are also several inner seal surfaces  98 . More specifically, there is an inner seal surface  98   a  which is part of the shaft  16 , inner seal surfaces  98   b   1 , 98   b   2  which are part of the boss  52   b,  another inner seal surface  98   c  which is part of the inner race  92 , and an inner seal surface  98   d  which is part of the outer race  94 . 
         [0032]    There are different types of seals which may be used to provide a sealing function at or around the bearing assembly  30   b.  An embodiment of a seal  100  used with the bearing assembly  30   b  is shown in  FIG. 4 , where the seal  100  is located between the bearing assembly  30   b  and the sidewall  14   a,  such that debris from the central port  14  is substantially prevented from contacting the bearing assembly  30   b.  The seal  100  includes a base portion  100   a  and two flange portions  100   b.  The base portion  100   a  is in contact with several of the inner seal surfaces  98   b   1 , 98   b   2 , 98   d,  one of the flange portions  100   b  is in contact with the inner seal surface  98   a  formed as part of the shaft  16  and one of the inner seal surfaces  98   b   1  formed as part of the boss  52   b , and another of the flange portions  100   b  is in contact with the inner seal surface  98   a  formed as part of the shaft  16  and one of the inner seal surfaces  98   c  formed as part of the inner race  92 . 
         [0033]    Another embodiment of a seal  102  is shown in  FIG. 5 , where this seal  102  is also located between the bearing assembly  30   b  and the side wall  14   a.  However, in this embodiment, the seal  102  includes an X cross-section, having inner flange portions  102   a  and outer flange portions  102   b.  One of the inner flange portions  102   a  is in contact with the inner seal surface  98   a  formed as part of the shaft  16  and one of the inner seal surfaces  98   c  formed as part of the inner race  92 , and another of the inner flange portions  102   a  is in contact with the inner seal surface  98   a  formed as part of the shaft  16  and one of the inner seal surfaces  98   b   1  formed as part of the boss  52   b.  One of the outer flange portions  102   b  is in contact with the inner seal surfaces  98   b   1 , 98   b   2  of the boss  52   b,  and another of the outer seal surfaces  102   b  is in contact with one of the inner seal surfaces  98   b   2  of the boss  52   b  and the inner seal surface  98   d  of the outer race  94 . 
         [0034]    The seal  102  may also be placed outside of the bearing assembly  30   b,  as shown in  FIG. 6 , such that the bearing assembly  30   b  is closer to the side wall  14   a  in relation to the seal  102 . In this embodiment, one of the inner flange portions  102   a  of the seal  102  is in contact with the outer seal surface  96   a  formed as part of the shaft  16 , the other inner flange portion  102   a  is in contact with the outer seal surface  96   a  of the shaft  16 , and the outer seal surface  96   c  formed as part of the inner race  92 . One of the outer flange portions  102   b  is in contact with the outer seal surface  96   b  formed as part of the boss  52   b , the other outer flange portion  102   b  is in contact with the outer seal surface  96   b  formed as part of the boss  52   b,  and the outer seal surface  96   d  formed as part of the outer race  94 . 
         [0035]    Another embodiment is shown in  FIG. 7 , where the shaft  16  has two diameters, a first diameter  16   a,  which is smaller than a second diameter  16   b.  Also shown in  FIG. 7  is the seal  102  having the X cross-section, where one of the inner flange portions  102   a  is in contact with the inner seal surface  98   c  of the inner race  92  and the inner seal surface  98   a  of the shaft  16 , and another of the inner flange portions  102   a  is in contact with two of the inner seal surfaces  98   a , 98   b   3  of the shaft  16 . Furthermore, one of the outer flange portions  102   b  is in contact with the inner seal surface  98   b   2  of the boss  52   a,  and the other outer flange portion  102   b  is in contact with the inner seal surfaces  98   b   1 , 98   b   2  of the boss  52   a.    
         [0036]    Yet another embodiment is shown in  FIG. 8 , with the shaft  16  also having two diameters  16   a , 16   b.  In this embodiment, a lip seal  104  is used having an outer base portion  104   a  and an inner lip portion  104   b.  In this embodiment, the outer base portion  104   a  of the lip seal  104  is in contact with the inner seal surfaces  98   b   1 , 98   b   2  of the boss  52 . The inner lip portion  104   b  is in contact with the inner seal surface  98   a  of the shaft  16 , and the inner seal surface  98   c  of the inner race  92 . 
         [0037]    Another embodiment of the present invention is shown in  FIG. 9 , with like numbers referring to like elements. In this embodiment, the shaft  16  again has two diameters  16   a , 16   b.  However, in this embodiment, the seal  102  is located on the second diameter  16   b,  which is the larger of the two diameters  16   a , 16   b.  In this embodiment, the housing  12  and the boss  52   a  are shaped differently to accommodate the change in location of the seal  102 . The inner race  92  is adjacent the portion of the shaft  16  having the second diameter  16   b,  but is still mounted to the portion of the shaft  16  having the first diameter  16   a.  The seal  102  having the X cross-section is used, but it is within the scope of the invention that seals of other shapes and cross-sections may be used as well. In this embodiment, one of the inner flange portions  102   a  is in contact with the inner seal surface  98   a  of the shaft  16 , and another of the inner flange portions  102   a  is in contact with the inner seal surface  98   a  of the shaft  16  and one of the inner seal surfaces  98   b   1  of the boss  52   a.  Also, one of the outer flange portions  102   b  is in contact with the inner seal surface  98   d  of the outer race  94  and the inner seal surface  98   b   2  of the boss  52   a,  and the other outer flange portion  102   b  is in contact with the inner seal surfaces  98   b   1 , 98   b   2  of the boss  52   a    
         [0038]    In operation, the spring  62  biases the sector gear  58 , and therefore the shaft  16  and valve plate  20  towards a closed position, such that the central port  14  is substantially closed, or blocked completely, depending upon how the assembly  10  is configured. When a current is applied to the motor  38 , the pinion gear  42  is rotated, which causes the rotation of the intermediate gear  44 , the middle gear  54 , and the sector gear  58 . To rotate the sector gear  58 , the force applied to the sector gear  58  by the return spring  62  is overcome. The amount of rotation of the sector gear  58  is in proportion to the amount of current applied to the motor  38 , which must overcome the force applied to the sector gear  58  by the return spring  62 . 
         [0039]    As the sector gear  58  is rotated, the shaft  16  is rotated as well, rotating the plate  20 , and allowing increased levels of air flow through the central port  14 . The amount of rotation of the sector gear  58  is detected by the sensor, such that the valve plate  20  may be placed in a desired position. The shaft  16  is supported by the bearing assemblies  30   a , 30   b,  and the seals  100 , 102 , 104  prevent leaking around the bearing assemblies  30   a , 30   b  during the operation of the throttle control assembly  10 . The throttle control assembly  10  may be used to control the flow of air, or any type of fluid, making the assembly  10  useful for many different applications, including applications where the assembly is exposed to high pressures. 
         [0040]    The description of the invention is merely exemplary in nature and, thus, 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.