Patent Abstract:
Provided is an impeller of a fuel pump for a vehicle. More particularly, an impeller of a fuel pump for a vehicle, which can improve delivery pressure and a delivery speed of fuel by modifying a shape of an impeller blade that is provided between an upper casing and a lower casing of a fuel pump and is joined to a rotational shaft of a driving motor to deliver fuel by using rotational force at the time of suctioning fuel from a fuel tank and supplying fuel to an engine of an internal combustion engine.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 to Korean Patent Application No. 10-2011-0030990, filed on Apr. 5, 2011, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The following disclosure relates to an impeller of a fuel pump for a vehicle. More particularly, the following disclosure relates to an impeller of a fuel pump for a vehicle, which can improve delivery pressure and a delivery speed of fuel by modifying a shape of an impeller blade that is provided between an upper casing and a lower casing of a fuel pump and is joined to a rotational shaft of a driving motor to deliver fuel by using rotational force at the time of suctioning fuel from a fuel tank and supplying fuel to an engine of an internal combustion engine. 
     BACKGROUND 
     In general, a fuel pump of a vehicle is mounted on the inside of a fuel tank of the vehicle and serves to suction fuel and pressure-feed the suctioned fuel to a fuel injection device mounted in an engine. 
     In addition, the fuel pump for the vehicle is classified into a mechanical fuel pump and an electrical fuel pump and a turbine type fuel pump  10  which is a type of electrical fuel pump is primarily used in an engine using gasoline as fuel. 
     In the turbine type fuel pump  10 , a driving motor  20  is provided in a motor housing  60  of the fuel pump  10 , an upper casing  30  and a lower casing  40  are provided on the bottom of the motor housing  60  to be closely attached to each other, and an impeller  50  is interposed therebetween, as shown in  FIG. 1 . 
     In addition, the impeller  50  is joined to a rotational shaft  21  of a driving motor  20 , such that the impeller  50  is configured to rotate with the driving motor  20 . 
     That is, as the impeller  50  rotates, a pressure difference is generated, and as a result, fuel is suctioned into the impeller  50  and while the pressure of fuel is increased due to a rotation flow generated by continuous rotation of the impeller  50 , fuel is ejected. 
     Therefore, fuel is introduced into a fuel suction opening  41  of the lower casing  40  to flow to a check valve  70  formed in an upper part of the motor housing  60  along an inner part of the motor housing  60  through a fuel ejection opening  31  of the upper casing  30  with the pressure thereof increased through the rotating impeller  50  and supplied to the fuel injection device mounted on the engine of the vehicle. 
     In this case, the impeller  50  is formed in a disk shape, a plurality of blades  51  are formed on an circumferential surface thereof in an outer direction of the circumferential surface, blade chambers  52  are formed among respective blades  51  to penetrate both surfaces of the impeller  50  as shown in  FIG. 2 , such that fuel is introduced into the fuel suction opening  41  of the lower casing  40  to generate the rotation flow in a space between the blade chamber  52  and a lower path groove  42  formed in the lower casing  40  and an upper path groove  32  formed in the upper casing  30  as shown in  FIG. 3 , and a circulation process in which fuel is again introduced into the neighboring blade chamber  52  to generate the rotation flow is repeated. Therefore, kinetic energy generated by the rotation of the impeller  50  is converted into pressure energy of fuel, and as a result, fuel is delivered to the fuel ejection opening  31  of the upper casing  30 . 
     In addition, in the impeller  50  in the related art, a circumference center guider  53  is formed at the center of the circumferential surface along the circumferential surface of the impeller  50  so as to efficiently generate the rotation flow formed in the space between the blade chamber  52  and the lower path groove  42  and the rotation flow generated in the space between the impeller chamber  52  and the upper path groove  32 . 
     However, with a current technological trend in which components in the vehicle are gradually subjected to a light weight, a compact size, and high performance in order to satisfy user&#39;s various preferences globally, a study about high performance of even the fuel pump has been required. 
     In addition, the amount of used pressure of the fuel pump is determined according to a specification of the vehicle and a high pressure is required as a recent trend. Therefore, the fuel pump mounted with the impeller in the related art is limitative in increasing an ejection amount of fuel under high pressure. 
     SUMMARY 
     An embodiment of the present invention is directed to providing an impeller of a fuel pump for a vehicle, which can improve delivery pressure and a delivery speed of fuel by forming a blade center guider for efficiently generating a rotation flow of fuel on an impeller blade that is provided between an upper casing and a lower casing of a fuel pump and is joined to a rotational shaft of a driving motor to deliver fuel by using rotational force. 
     In one general aspect, an impeller of a fuel pump for a vehicle includes: an impeller body having a disk shape, having a circumference center guider that protrudes along the center of a circumferential surface, and having a shaft fixation hole that penetrates at the center into which a rotation shaft of a driving motor is inserted and joined; and a plurality of blades formed on an outer circumferential surface of the impeller body at predetermined intervals in an outer direction of the circumferential surface, wherein each of the plurality of blades has a blade center guider formed on an impeller rotation direction surface in a radial direction and protruding at the center thereof to thereby be connected with the circumference center guider. 
     Further, the impeller may further include a side ring formed on an outer circumferential surface of the plurality of blades so as to form a blade chamber allowing fuel to be discharged and introduced in the upper and lower parts of the blade, respectively. 
     An edge at which a surface of the blade center guider and a surface of the blade contact each other and an edge at which the blade center guider and the circumference center guider are connected to each other may be rounded. 
     Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view illustrating a schematic configuration of a fuel pump for a vehicle in the related art. 
         FIG. 2  is a perspective view illustrating a structure of an impeller in the related art. 
         FIG. 3  is a partial cross-sectional view illustrating the impeller, an upper casing, and a lower casing in the related art. 
         FIG. 4  is a perspective view and a partial enlarged diagram illustrating an impeller of a fuel pump for a vehicle according to an exemplary embodiment. 
         FIG. 5  is a cross-sectional view taken along line B-B′ of  FIG. 4 . 
         FIG. 6  is a front view illustrating a cross section of the impeller according to the exemplary embodiment. 
         FIG. 7  is a cross-sectional view taken along line A-A′ of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The advantages, features and aspects of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings, which is set forth hereinafter. The present invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. 
     An impeller of a fuel pump for a vehicle according to an exemplary embodiment of the present invention includes: an impeller body  100  having a disk shape, having a circumference center guider  110  that protrudes along the center of a circumferential surface, and having a shaft fixation hole  120  that penetrates at the center into which a rotation shaft of a driving motor is inserted and joined; and a plurality of blades  200  formed on an outer circumferential surface of the impeller body  100  at predetermined intervals in an outer direction of the circumferential surface, wherein each of the plurality of blades  200  has a blade center guider  220  formed on an impeller rotation direction surface in a radial direction and protruding at the center thereof to thereby be connected with the circumference center guider  110 . 
     Hereinafter, the respective components will be described in more detail with reference to the accompanying drawings. 
       FIG. 4  is a perspective view and a partial enlarged diagram illustrating an impeller of a fuel pump for a vehicle according to an exemplary embodiment. 
     In the impeller of a fuel pump for a vehicle according to the exemplary embodiment, a plurality of blades  200  are formed on a circumferential surface of an impeller body  100  that is formed in a disk shape and has a shaft fixation hole  120  formed at the center thereof in an outer direction of the circumferential surface. 
     In this case, the respective blades  200  are formed in a thickness direction of the impeller body  100  and the plurality of blades  200  are formed at predetermined intervals and blade chambers  210  are formed among the blades  200 . 
     That is, the blade chamber  210  is a space formed between two neighboring blades  200 . 
     In this case, when the impeller rotates, fuel is introduced into the blade chamber  210  to generate a rotation flow between an upper path groove  32  and a lower path groove  42  respectively formed in an upper casing  30  and a lower casing  40  provided in an upper part and a lower part of the impeller to correspond to the position of the blade chamber  210 , such that the pressure of fuel increases. 
     In addition, as shown in  FIG. 5 , a circumference center guider  110  protrudes along the center of the circumferential surface of the impeller body  100 . 
     The circumference center guider  110  allows the fuel introduced into the blade chamber  210  to more efficiently generate the rotation flow generated in the upper part and the lower part of the blade chamber  210 , respectively. 
     Further, each of the plurality of blades  200  has a blade center guider  220  formed on an impeller rotation direction surface in a radial direction and protruding at the center thereof to thereby be connected with the circumference center guider  110 . 
       FIG. 7  is a cross-sectional view taken along line A-A′ of  FIG. 4  and illustrates a cross section cutting an upper part of the blade center guider  220  at the center of the thickness of the impeller. 
     Further, in the impeller, an edge at which a surface of the blade center guider  220  and a surface of the blade  200  contact each other and an edge at which the blade center guider  220  and the circumference center guider  110  is connected to each other may be rounded as shown in  FIG. 7 . 
     Therefore, the rotation flows are efficiently generated in the upper part and the lower part of the blade chamber  210  by the blade  200  and the circumference center guider  110  depending on the rotation of the impeller and the rotation flow is more efficiently generated by the blade center guider  220  to minimize energy loss caused due to turbulence and a change in path, thereby improving a delivery pressure and a delivery speed of fuel as shown in  FIG. 5 . 
     In addition, the blade  200  has a shape in which the upper part and the lower part of the blade  200  are formed by predetermined slopes to be symmetrical to each other around the circumference center guider  110  as shown in  FIG. 4  or  6 , but an inside part and an outside part in a circumferential direction of the impeller body  100  of the blade  200  may be bent to form an end and may have various shapes such as a flat plate shape or a round shape. 
     Further, the blade  200  is formed in the outer direction of the circumferential surface along the circumferential surface of the impeller body  100  and may be in a radial direction at the center of the impeller body  100  and may be formed to have a predetermined angle to the radial direction and may be formed to have a predetermined angle to the radial direction and have a predetermined curvature in a longitudinal direction of the blade. 
     Further, the plurality of blades  200  are formed on the circumferential surface of the impeller body  100  at predetermined intervals and the intervals among the respective blades  200  may be the same as each other or different from each other. 
     However, the impeller having the aforementioned configuration is an impeller applied to an open channel type vehicular fuel pump in which the plurality of blades  200  are formed in the impeller body  100 , such that the upper part, the lower part, and an outer part of the blade chamber  210  are all opened. 
     That is, in the open channel type, the fuel introduced into the blade chamber  210  is pushed out in the outer direction of the circumferential surface of the impeller body  110  by the rotation of the impeller to form the rotation flow. 
     Therefore, the impeller may further include a side ring  300  formed on an outer circumferential surface of the plurality of blades  200  so that fuel is discharged and introduced in the upper and lower parts of the blade  200 , respectively and the blade chamber  210  for forming the rotation flow is formed. 
     That is, the impeller may be applied to a side channel type vehicular fuel pump in which the upper and lower parts of the blade chamber  210  are opened and the outer part of the blade chamber  210  is blocked by the side ring  300 , such that the fuel is discharged or introduced only in the upper and lower parts of the blade chamber  210 . 
     Further, a guider protrudes at the center of an inner peripheral surface of the side ring  300  like the circumference center guider  110  formed on the outer peripheral surface of the impeller body  100  to more efficiently generate the rotation flow of the fuel in the blade chamber  210 . 
     According to an embodiment of the present invention, an impeller of a fuel pump for a vehicle can improve a delivery pressure and a delivery speed of fuel by minimizing energy loss caused due to turbulence and a change in path while fuel introduced into a blade chamber of the impeller forms a rotation flow by forming a blade center guider on an impeller blade that is provided between an upper casing and a lower casing of a fuel pump and is joined to a rotational shaft of a driving motor to deliver fuel by using rotational force. 
     The present invention is not limited to the aforementioned exemplary embodiment and an application range is various and it is apparent that various modifications can be made to those skilled in the art without departing from the spirit of the present invention described in the appended claims.

Technology Classification (CPC): 5