Patent Abstract:
A device for supplying fuel from a tank in which the mount of the fuel-supply pump, in which the mount is simpler and less expensive than the known devices because the number of components is reduced through the integration of functions. The mount of the fuel-supply pump is embodied as a rigid conduit and has a first fuel supply line section that is connected to the outlet fitting of the fuel-supply pump. The transmission of noise to the mount is reduced.

Full Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention is directed to an improved device for supplying fuel from a tank to an internal combustion engine.  
           [0003]    2. Description of the Prior Art  
           [0004]    A fuel supply device is known from DE 196 19 992 A1, in which a fuel-supply pump is supported with its housing in a cylindrical mount and is fixed in the cylindrical mount by means of a pressurized connection fitting that is slid onto an outlet fitting of the fuel-supply pump. The cylindrical mount is also flexibly supported by noise-damping suspension elements so that noise generated by the fuel-supply pump cannot be transmitted to the tank via the mount. The pressure connection fitting is attached to a main filter of the device via a flexible tube. It is disadvantageous that the mount requires a large amount of space and is comparatively complex and costly.  
         OBJECT AND SUMMARY OF THE INVENTION  
         [0005]    The device according to the invention has the advantage over the prior art in that the mount of the fuel-supply pump is simplified and in that the mount is embodied as a rigid conduit and has a first fuel supply line section that is connected to the outlet fitting of the fuel-supply pump. In this manner, the first fuel supply line section is integrated into the mount, thus reducing the number of components and reducing the production costs.  
           [0006]    It is particularly advantageous to attach the fuel-supply pump to the mount only by means of the outlet fitting since this makes it possible to reduce the transmission of noise to the tank. It also significantly simplifies assembly.  
           [0007]    It is also advantageous if the mount has a mount fitting with a mount conduit that feeds with an opening into the first fuel supply line section since this makes it particularly easy to fasten the outlet fitting of the fuel-supply pump in the mount conduit.  
           [0008]    It is advantageous if the outlet fitting of the fuel-supply pump is inserted into the mount conduit and passes through a mounting element provided in the connection opening because this produces a positively engaging connection between the mounting element and the outlet fitting.  
           [0009]    It is also advantageous if the mounting element engages in detent fashion in a mounting groove of the outlet fitting since this permits the production of a simple and reliable detent connection.  
           [0010]    Because the fuel-supply pump is fastened to the outlet fitting only at the mounting element, it is also advantageous to make the mounting element out of an elastic material since this can significantly reduce amount of fuel-supply pump noise that is transmitted to the tank via the mount.  
           [0011]    It is very advantageous if the mount has a first shoulder in the connection opening, against which the mounting element rests; a second shoulder fixes the mounting element against the first shoulder in cantilevered fashion. The fuel-supply pump is thus firmly fixed in the mount.  
           [0012]    It is also advantageous to fix the mounting element against the first shoulder by means of at least one hold-down element since this also firmly anchors the fuel-supply pump in the mount.  
           [0013]    It is additionally advantageous if the mounting element is flat and disk-shaped since this makes the mounting element particularly inexpensive to produce.  
           [0014]    It is advantageous to embody the mounting element as a curved shaped part because this facilitates production of the detent connection.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments, taken in conjunction with the drawings, in which:  
         [0016]    [0016]FIG. 1 shows a sectional view of a device incorporating the invention for supplying fuel,  
         [0017]    [0017]FIG. 2 shows an enlarged, fragmentary three-dimensional view of the device according to FIG. 1,  
         [0018]    [0018]FIG. 3 shows a first exemplary embodiment of the invention,  
         [0019]    [0019]FIG. 4 shows a fuel-supply pump with an outlet fitting according to the invention,  
         [0020]    [0020]FIG. 5 shows a second exemplary embodiment of the invention,  
         [0021]    [0021]FIG. 6 shows a sectional view of the second exemplary embodiment,  
         [0022]    [0022]FIG. 7 shows a third exemplary embodiment of the invention, and  
         [0023]    [0023]FIG. 8 shows a fourth exemplary embodiment.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]    The fuel supply device shown in FIG. 1 serves, for example, to supply fuel from a tank  1  to a collecting receptacle  2  and from there, via a fuel-supply pump  3 , to an internal combustion engine  4  of a motor vehicle.  
         [0025]    The tank  1  contains the collecting receptacle  2 , which in turn contains the fuel-supply pump  3 . The for example cup-shaped collecting receptacle  2  stores enough fuel to assure a sufficient supply of fuel to the internal combustion engine  4  by means of the fuel-supply pump  3  even when no fuel is being supplied into the collecting receptacle  2 , for example because the vehicle is negotiating a curve and thus causing sloshing movements of the fuel in the tank  1 .  
         [0026]    The fuel-supply pump  3  draws fuel from the collecting receptacle  2 , for example via a prefilter  5  and an intake line  6 , and supplies the fuel to the internal combustion engine  4 , for example via a first fuel supply line section  8 . 1 , a check valve  9 , a second fuel supply line section  8 . 2 , a main filter  10 , and a third fuel supply line section  8 . 3   
         [0027]    Starting from the third fuel supply line section  8 . 3 , an excess pressure line  13  leads to a pressure regulating valve  14 . If the pressure in the third fuel supply line section  8 . 3  and therefore in the excess pressure line  13  exceeds a preset pressure, then the pressure regulating valve  14  opens and allows fuel to flow back into the collecting receptacle  2  via the excess pressure line  13  and the pressure regulating valve  14 . This reduces the pressure in the third fuel supply line section  8 . 3  back to below the preset pressure and the pressure regulating valve  14  closes again.  
         [0028]    For example, the fuel-supply pump  3  is a flow-type pump that is driven electrically by an actuator, for example an armature of an electric motor.  
         [0029]    The prefilter  5  protects the device downstream of the prefilter  5  from coarse particulate matter contained in the fuel.  
         [0030]    When the fuel-supply pump  3  is switched off, the check valve  9  prevents fuel from flowing back out of the fuel supply line ( 8 . 3 ,  8 . 2 ) downstream of the check valve  9  and into the collecting receptacle  2  via the first fuel supply line section  8 . 1 , the fuel-supply pump  3 , the intake line  6 , and the prefilter  5 .  
         [0031]    The main filter  10  filters out the fine particulate matter contained in the fuel.  
         [0032]    The first fuel supply line section  8 . 1  is connected to the collecting receptacle  2  for example via a branch line  11 , a throttle  12 , a propulsion line  15 , and a so-called aspirating jet pump  16 .  
         [0033]    In order to prevent the fuel-supply pump  3  from emptying the collecting receptacle  2 , there must be a continuous replenishing flow of fuel from the tank  1  into the collecting receptacle  2 . To this end, the aspirating jet pump  16  draws fuel from the tank  1  for example via a bottom valve  17  and an intake conduit  18 . The aspirated fuel is conveyed into the collecting receptacle  2  along with the so-called propulsion jet of the propulsion line  15 .  
         [0034]    An aspiration jet pump is known, for example, from DE 198 56 298 C1, the disclosure of which is incorporated herein by reference.  
         [0035]    The fuel-supply pump  3  has a housing with an inlet fitting  20  and an outlet fitting  21 . The intake line  6  is connected to the inlet fitting  20 , while the outlet fitting  21  is connected to the first fuel supply line section  8 . 1 .  
         [0036]    [0036]FIG. 2 shows a three-dimensional view of the device according to the invention from FIG. 1.  
         [0037]    In the device according to FIG. 2, parts that are the same or function in the same manner as those in the device according to FIG. 1 are provided with the same reference numerals.  
         [0038]    The fuel-supply pump  3  is fastened to a mount  27  that is embodied as a rigid conduit. The mount  27  contains the first fuel supply line section  8 . 1 . The end of the mount  27  oriented toward the main filter  10  is connected to the main filter  10 . The length of the mount  27  extends beyond the edge of the main filter  10  in the direction of the fuel-supply pump  3 . The fuel-supply pump  3  is fastened into the mount  27  by means of a detent connection.  
         [0039]    [0039]FIG. 3 shows a partial section through a first exemplary embodiment.  
         [0040]    In the device according to FIG. 3, parts that are the same or function in the same manner as those in the device according to FIGS. 1 and 2 are provided with the same reference numerals.  
         [0041]    For example, the fuel-supply pump  3  has a housing  22  with a cylindrical housing section  23 , whose end oriented toward the inlet fitting  20  is sealed shut by a pump cover and whose end oriented toward the outlet fitting  21  is sealed shut by an outlet cover  24 .  
         [0042]    The end of the mount  27  oriented toward the fuel-supply pump  3  has a mount fitting  28  that is cylindrical, for example. The mount fitting  28  has a mount conduit  25  that feeds from the end of the mount fitting  28  oriented toward the fuel-supply pump  3 , through a connection opening  31 , and into the first fuel supply line section  8 . 1 . The cross section of the mount fitting  28  is slightly greater than the cross section of the outlet fitting  21  of the fuel-supply pump  3  so that the outlet fitting  21  can be slid into the mount conduit  25  of the mount fitting  28 . At the end oriented toward the fuel-supply pump  3 , the mount fitting  28  has a first bevel  32  to facilitate the insertion of the outlet fitting  21 . The cross section of the mount fitting  28  is circular, for example.  
         [0043]    The outer circumference of outlet fitting  21  of the fuel-supply pump  3  has an annular sealing groove  29  in which a sealing ring  30 , for example an O-ring, is provided. Downstream of the sealing groove  29 , a number of pocket-shaped recesses  33  are provided on the outer circumference of the outlet fitting  21 , for example distributed over its circumference. Further downstream of the pocket-shaped recesses  33 , the outer circumference of the outlet fitting  21  is provided with a mounting groove  34  that extends around its entire circumference. The mounting groove  34  is round, for example, or is embodied as a square groove (FIG. 4). The outlet fitting  21  is provided with a conical bevel  38  at its end oriented away from the outlet cover  24 .  
         [0044]    The cross section of the first fuel supply line section  8 . 1  is composed, for example, of a rectangle  36  and a circular or arcuate segment  37 . The cross section of the first fuel supply line section  8 . 1 , however, can also be composed of only the circular segment  37 , or can be entirely circular, rectangular, or elliptical.  
         [0045]    The transition from the mount fitting  28  to the first fuel supply line section  8 . 1  forms a first shoulder  35 . The first shoulder  35  is adjoined by second shoulder  39  that is of one piece with it and embraces a mounting element  41  that rests against the first shoulder  35  in cantilevered fashion. The second shoulder  39  fixes the mounting element  41  on the first shoulder  35 . A width  43  of the rectangle  36  in the vicinity of the connection opening  31  is greater than a diameter  44  of the circular segment  37  so that the first shoulder  35  and the second shoulder  39  together constitute an indentation  40 .  
         [0046]    For example, the mounting element  41  is embodied as disk-shaped. The mounting element  41  is polygonal, for example square, hexagonal, or octagonal, with respective pairs of parallel sides; two parallel, opposing sides rest against the second shoulder  39  so that the mounting element  41  is supported in a non-rotating fashion in the first fuel supply line section  8 . 1 . The mounting element  41  can, however, also be circular or elliptical. The mounting element  41  is made of an elastic material, for example rubber.  
         [0047]    The mounting element  41  has a for example square opening  42  that is smaller than the connection opening  31 . The opening  42 , however, can also be circular or polygonal.  
         [0048]    The mounting element  41  is slid into the indentation  40  through a lateral conduit opening  47 . The width  43  of the rectangle  36  is reduced in step fashion in the axial extension of the first fuel supply line section  8 . 1 , thus forming a stop for the mounting element  41 . The stop centers the mounting element  41  in relation to the connection opening  31  of the mount fitting  28  so that the opening  42  of the mounting element  41  is concentric to the connection opening  31 . After the insertion of the mounting element  41 , a side cover  46  closes the lateral conduit opening  47 .  
         [0049]    In order to attach the fuel-supply pump  3  to the mount  27 , the outlet fitting  21  of the fuel-supply pump  3  is slid into mount fitting  28  provided with the mounting element  41 . The outlet fitting  21  is pushed, with its bevel  38  first, through the opening  42  of the mounting element  41 . As a result, first the bevel  38  elastically stretches the opening  42  until it is the same size as the outer diameter of the outlet fitting  21  and then the outlet fitting  21  travels further through the opening  42  until the mounting groove  34  of the outlet fitting  21  reaches the opening  42 . Since the outer diameter of the outlet fitting  21  decreases in step fashion at the mounting groove  34 , the elastically stretched opening  42  contracts again, fits elastically into the inner diameter of the mounting groove  34 , and thus engages in the mounting groove  34  in detent fashion. As a result, the outlet fitting  21  extends through the opening  42  of the mounting element  41  as it engages in the mount fitting  28 . This detent connection attaches the fuel-supply pump  3  to the mount  27 . If the opening  42  is square and the mounting groove  34  is a square groove, then this produces a non-rotating detent connection.  
         [0050]    The mounting element  41  absorbs virtually all of the forces acting in the direction of the mount fitting  28 , for example the weight of the fuel-supply pump, and transmits them to the mount  27 . The elasticity of the mounting element  41  damps both mechanical vibrations and acoustical vibrations. Consequently, hardly any acoustical vibrations (noise) that are generated by the fuel-supply pump  3  are transmitted by mounting element  41  to the mount  27 , thus permitting a reduction in the audible noise level of the fuel-supply pump  3  in the vehicle.  
         [0051]    The sealing ring  30  in the sealing groove  29  seals a gap between the outlet fitting  21  and the mount fitting  28  so that, for example, no fuel can escape from the first fuel supply line section  8 . 1  to the outside.  
         [0052]    [0052]FIG. 4 shows the fuel-supply pump  3  with the outlet fitting  21 .  
         [0053]    In the device according to FIG. 4, parts that are the same or function in the same manner as those in the device according to FIGS. 1 and 3 are provided with the same reference numerals.  
         [0054]    The outlet fitting  21  can have additional pocket-shaped recesses  56  distributed over the circumference of its bevel  38 .  
         [0055]    [0055]FIG. 5 shows a second exemplary embodiment of the device according to the invention, without a fuel-supply pump  3 .  
         [0056]    In the device according to FIG. 5, parts that are the same or function in the same manner as those in the device according to FIGS.  1  to  4  are provided with the same reference numerals.  
         [0057]    The device according to FIG. 5 differs from the device according to FIG. 3 in that a centering plate  45  disposed perpendicular to the side cover  46  positions the mounting element  41  centrally in relation to the connection opening  31 .  
         [0058]    As in the exemplary embodiment according to FIG. 3, after the insertion of the mounting element  41 , the side cover  46  covers the lateral conduit opening  47  of the mount  27  and seals it off from the environment. The centering plate  45  disposed on the side cover  46  has for example protruding centering means  48  that are disposed, for example, uniformly distributed around the circumference of an additional opening  52  in the centering plate  45 . The additional opening  52  in the centering plate  45  is larger than the opening  42  of the mounting element  41 . The mounting element  41  is slid onto the centering plate  45  of the side cover  46 ; the centering means  48 , for example centering pins or centering ribs, engage in centering openings  49  of the mounting element  41 .  
         [0059]    The centering plate  45  is slid with the mounting element  41  into the indentation  40  of the mount  27  until the side cover  46  closes the side conduit opening  47 . After the insertion, the centering plate  45  is approximately parallel to the first shoulder  35 . The mounting element  41  rests against the shoulder  35 . For example, the side cover  46  is welded to the mount  27 . However, the side cover  46  can also be glued or flange-mounted to the wall of the lateral conduit opening  47 .  
         [0060]    Then the outlet fitting  21  of the fuel-supply pump  3  can be slid into the mount fitting  28 . The centered mounting element  41  permits the outlet fitting  21  to reliably and simply engage in detent fashion in the mount  27 , as described above.  
         [0061]    [0061]FIG. 6 shows the second exemplary embodiment in a partial sectional view, with the outlet fitting  21  of the fuel-supply pump  3  detent engaged in the mount  27 .  
         [0062]    In the device according to FIG. 6, parts that are the same or function in the same manner as those in the device according to FIGS.  1  to  5  are provided with the same reference numerals.  
         [0063]    After being inserted, the outlet fitting  21  engages in detent fashion in the mount fitting  28  and reaches through both the opening  42  and the additional opening  52 . In order to accommodate the centering plate  45 , the indentation  40  is taller in the direction of the mount fitting  28  than the indentation  40  in the first exemplary embodiment according to FIG. 3.  
         [0064]    [0064]FIG. 7 shows a partial sectional view of a third exemplary embodiment.  
         [0065]    In the device according to FIG. 7, parts that are the same or function in the same manner as those in the device according to FIGS.  1  to  6  are provided with the same reference numerals.  
         [0066]    The device according to FIG. 7 differs from the device according to FIG. 3 in that the mounting element  41  is fixed against the first shoulder  35  not by the second shoulder  39 , but by hold-down elements  55 . The second shoulder  39  is eliminated in this third exemplary embodiment.  
         [0067]    The mount  27  is divided in the axial direction and is comprised of an upper part  53  with the circular segment  37  and a lower part  54  with the mount fitting  28  and the first shoulder  35 . The hold-down elements  55  are disposed on the side of the upper part  53  oriented toward the lower part  54 , protrude toward the first shoulder  35  of the lower part  54 , and rest against the mounting element  41  so that the mounting element  41  is fixed against the first shoulder  35 .  
         [0068]    The division in two of the first fuel supply line section  8 . 1  makes it possible for the holding element  41  to be inserted into the lower part  54  of the mount  27 . After the insertion of the mounting element  41 , the upper part  53  is slid into the lower part  54  and, for example, welded or glued in place. However, the upper part  53  and the lower part  54  can also be clipped to each other. A separate side cover  46  is not required since it is already formed onto the upper part  53  or the lower part  54 .  
         [0069]    [0069]FIG. 8 shows a sectional view of a fourth exemplary embodiment.  
         [0070]    In the device according to FIG. 8, parts that are the same or function in the same manner as those in the device according to FIGS.  1  to  7  are provided with the same reference numerals.  
         [0071]    The device according to FIG. 8 differs from the device according to FIG. 7 in that the mounting element  41  is not embodied as flat, but as a curved shaped part. To this end, the elastic mounting element  41  is produced, for example, by means of injection molding. An inner region  59  of the mounting element  41  encompasses the opening  42 ; an outer region  60  constitutes the outer circumference of the mounting element  41  and is spaced apart in the axial direction from the inner region  59  due to the curvature of the mounting element  41 .  
         [0072]    The mounting element  41  rests with its inner region  59  in the mounting groove  34  and rests with its outer region  60  against the first shoulder  35 . The mounting groove  34  is embodied as longer in the direction of the outlet fitting  21  than those according to FIGS. 3, 5,  6 , and  7  since starting from the inner region  59 , the mounting element  41  in the mounting groove  34  extends first in the direction of the outlet fitting  21  and then curves outward in the direction of the first shoulder  35 . The hold-down elements  55  protrude in the direction of the first shoulder  35  and press the inner region  59  into the mounting groove  34  while pressing the outer region  60  of the mounting element  41  against the first shoulder  35 . The inner region  59  of the mounting element  41  rests against an upper side surface  61  of the mounting groove  34 . The forces of the fuel-supply pump  3  act on the inner region  59  of the mounting element  41  via the upper side surface  61  and are transmitted to the mount  27  via the first shoulder  35 .  
         [0073]    The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.

Technology Classification (CPC): 5