Fuel pump

Abstract

A filter device is connected to a fuel pump for supplying filtered fuel to an internal combustion engine. The filter device has a bag-shaped filter element forming therein a fuel passage, wherein fuel passes through the filter element to enter into the fuel passage. The filter element further forms a vapor pooling chamber above the fuel passage, so that vapors separated from the filtered fuel in the fuel passage are moved toward the vapor pooling chamber. A valve device is provided at a portion of the filter device, which is close to the vapor pooling chamber, so that vapors are discharged from the vapor pooling chamber to an outside of the filter device.

1 . A fuel pump comprising:
 a pump device having a suction port and a discharge port, the pump device generating fuel suction force at the suction port and discharging pressurized fuel from the discharge port; and   a filter device connected to the suction port for filtering the fuel to be sucked into the pump device,   wherein the filter device includes;   an outer shell having a filter element of a film shape for filtering the fuel to be sucked into the pump device, the outer shell further having a fuel passage for guiding the fuel filtered by the filter element to the suction port of the pump device, and the outer shell further having a vapor pooling chamber formed above the fuel passage and communicated with the fuel passage so that vapors included in the fuel flowing through the fuel passage are moved from the fuel passage toward the vapor pooling chamber, and   a valve device provided at a portion of the outer shell for communicating the vapor pooling chamber to an outside of the outer shell when an amount of the vapors pooled in the vapor pooling chamber reaches at a predetermined value.   
     
     
         2 . The fuel pump according to the  claim 1 , wherein
 a liquid film of the fuel is formed at a surface of the filter element when the fuel entered into the filter element, and   the liquid film of the fuel allows the fuel to pass through the filter element but prevents the vapors from passing through the filter element.   
     
     
         3 . The fuel pump according to the  claim 1 , wherein
 the outer shell has a slope wall portion at an upper side thereof, and the slope wall portion is upwardly inclined such that a height of the slope wall portion becomes larger as the slope wall portion is closer to the valve device.   
     
     
         4 . The fuel pump according to the  claim 3 , wherein
 the slope wall portion is formed by the filter element.   
     
     
         5 . The fuel pump according to the  claim 3 , wherein
 the slope wall portion is upwardly inclined such that the height of the slope wall portion becomes larger as the slope wall portion is further away from the suction port.   
     
     
         6 . The fuel pump according to the  claim 3 , wherein
 the valve device is provided at a highest position of the outer shell.   
     
     
         7 . The fuel pump according to the  claim 1 , wherein the valve device comprises:
 a valve seat member having a seat portion formed at an outer surface of the filter device and a communication hole formed at an inner area of the seat portion for communicating the vapor pooling chamber to the outside of the filter device; and   a valve body member disposed at the outer surface of the filter device, the valve body member being pushed by the vapors in the vapor pooling chamber and thereby being separated from the seat portion so that the valve body member allows the vapors to flow from the vapor pooling chamber to the outside of the filter device, while the valve body member being seated on the seat portion when the amount of the vapors in the vapor pooling chamber is decreased so that the valve body member prevents the fuel from flowing from the outside of the filter device into the inside of the filter device.   
     
     
         8 . The fuel pump according to the  claim 1 , wherein
 the fuel passage is composed of a first fuel passage and a second fuel passage, the second fuel passage being formed between the first fuel passage and the suction port of the pump device so that the first fuel passage is communicated to the suction port,   the outer shell is composed of the filter element and a tank wall member of a tank portion, the filter element forming therein the first fuel passage, the tank portion forming therein the second fuel passage and the vapor pooling chamber above the second fuel passage,   the filter element is provided at a lower end of the tank portion, so that the first fuel passage is communicated to the second fuel passage, and   the valve device is provided at a portion of the tank portion, at which the vapor pooling chamber is formed.   
     
     
         9 . The fuel pump according to the  claim 8 , wherein the valve device comprises:
 a valve seat member provided at the tank portion, the valve seat member having a seat portion formed at an outer surface of the filter device and a communication hole formed at an inner area of the seat portion for communicating the vapor pooling chamber to the outside of the filter device; and   a valve body member disposed at the outer surface of the filter device, the valve body member being pushed by the vapors in the vapor pooling chamber and thereby being separated from the seat portion so that the valve body member allows the vapors to flow from the vapor pooling chamber to the outside of the filter device, while the valve body member being seated on the seat portion when the amount of the vapors in the vapor pooling chamber is decreased so that the valve body member prevents the fuel from flowing from the outside of the filter device into the inside of the filter device.   
     
     
         10 . The fuel pump according to the  claim 8 , further comprising:
 an auxiliary jet pump provided between the first fuel passage and the second fuel passage,   wherein the auxiliary jet pump includes;   a throat portion forming a fuel jet passage, one end of which is opened to the first fuel passage and the other end of which is opened to the second fuel passage, and   a fuel jet portion provided in the fuel jet passage for emitting fuel toward the other end of the fuel jet passage opened to the second fuel passage.   
     
     
         11 . The fuel pump according to the  claim 1 , further comprising:
 a filter frame provided in the filter device for supporting an inner surface of the outer shell.   
     
     
         12 . The fuel pump according to the  claim 1 , further comprising:
 the pump device is composed of an electric pump for generating the fuel suction force in order to draw the fuel from the suction port, the electric pump pressurizes the fuel and discharges such pressurized fuel from the discharge port.   
     
     
         13 . The fuel pump according to the  claim 1 , further comprising:
 a jet pump includes;   a throat portion forming a fuel jet passage having an inlet open end and an outlet open end; and   a fuel jet portion provided in the fuel jet passage for emitting fuel toward the outlet open end, so that fuel suction force is generated at the inlet open end,   wherein the fuel sucked into the fuel jet passage from the inlet open end is discharged from the outlet open end together with the fuel emitted from the fuel jet portion.   
     
     
         14 . A fuel supply system for a vehicle comprising:
 an electric pump device arranged in a fuel tank for supplying fuel to an engine of the vehicle; and   a filter device connected to a suction port of the electric pump device for filtering fuel to be sucked into the electric pump device,   wherein the filter device includes;   a bag-shaped filter element forming therein a fuel passage into which the fuel in the fuel tank enters by passing through the filter element, the filter element further forming therein a vapor pooling chamber above the fuel passage so that vapors separated from the fuel are moved to the vapor pooling chamber; and   a valve device provided at a portion of the bag-shaped filter element which is close to the vapor pooling chamber, the valve device being opened when an amount of vapors exceeds a predetermined value so as to communicate the vapor pooling chamber to an outside of the filter device to thereby discharge the vapors to the outside thereof.   
     
     
         15 . A fuel supply system for a vehicle comprising:
 an electric pump device arranged in a fuel tank for supplying fuel to an engine of the vehicle;   a pressure regulating device for regulating fuel pressure of the fuel to be supplied to the engine; and   a filter device connected to a suction port of the electric pump device for filtering fuel to be sucked into the electric pump device,   wherein the filter device includes;   a bag-shaped filter element forming therein a first fuel passage into which the fuel in the fuel tank enters by passing through the filter element;   a tank portion forming therein a second fuel passage, the tank portion having a coupling portion connected to the suction port of the electric pump device so that the fuel from the second fuel passage is supplied to the electric pump device, the tank portion further having a vapor pooling chamber above the second fuel passage so that vapors separated from the fuel are moved to the vapor pooling chamber;   a jet pump provided between the filter element and the tank portion, the jet pump having a throat portion forming a fuel jet passage having an inlet open end and an outlet open end, the jet pump further having a fuel jet portion provided in the fuel jet passage for emitting surplus fuel from the pressure regulating device toward the outlet open end so that fuel suction force is generated at the inlet open end, and the fuel sucked into the fuel jet passage from the inlet open end being discharged from the outlet open end together with the surplus fuel emitted from the fuel jet portion; and   a valve device provided at a portion of the tank portion which is close to the vapor pooling chamber, the valve device being opened when an amount of vapors exceeds a predetermined value so as to communicate the vapor pooling chamber to an outside of the filter device to thereby discharge the vapors to the outside thereof.   
     
     
         16 . A fuel supply system for a vehicle comprising:
 an electric pump device arranged in a first tank portion of a saddle-type fuel tank for supplying fuel to an engine of the vehicle;   a pressure regulating device for regulating fuel pressure of the fuel to be supplied to the engine;   a jet pump arranged in a second tank portion of the fuel tank;   a filter device also arranged in the second tank portion and connected to the jet pump for filtering fuel in the second tank portion;   a fuel transfer pipe connected at one end to the jet pump and communicated at the other end to the first tank portion,   wherein the jet pump includes;   a throat portion forming a fuel jet passage having an inlet open end connected to the filter device and an outlet open end connected to the fuel transfer pipe; and   a fuel jet portion provided in the fuel jet passage for emitting surplus fuel from the pressure regulating device toward the outlet open end so that fuel suction force is generated at the inlet open end, the fuel sucked into the fuel jet passage from the filter device being discharged from the outlet open end together with the surplus fuel emitted from the fuel jet portion, and the fuel discharged from the jet pump being transferred to the first tank portion via the fuel transfer pipe, and   wherein the filter device includes;   a bag-shaped filter element forming therein a fuel passage into which the fuel from the second fuel tank enters through the filter element, the filter element further forming therein a vapor pooling chamber above the fuel passage; and   a valve device provided at a portion of the bag-shaped filter element which is close to the vapor pooling chamber, the valve device being opened when an amount of vapors exceeds a predetermined value so as to communicate the vapor pooling chamber to an outside of the filter device to thereby discharge the vapors to the outside thereof.