JP5012614B2 - Fuel supply device - Google Patents

Description

  The present invention relates to a fuel supply device that supplies fuel inside a fuel tank to a fuel consuming device (for example, an engine) provided outside the fuel tank.

  2. Description of the Related Art Conventionally, there has been known a fuel supply device that is connected in parallel to an internal combustion engine provided outside a fuel tank and includes two fuel pumps housed in the fuel tank (see Patent Document 1). In the fuel supply device of Patent Document 1, the two fuel pumps are accommodated in a sub tank that temporarily accumulates fuel. A differential pressure valve that opens and closes by a differential pressure inside and outside the sub tank is provided at the bottom of the sub tank. According to this, when the fuel pressure outside the sub tank is higher than the fuel pressure inside the sub tank, the fuel outside the sub tank is supplied into the sub tank.

There is also known a fuel supply apparatus that includes a pumping means for forcibly pumping fuel outside the sub tank into the sub tank (see Patent Document 2). This pumping means uses part of the fuel discharged from the fuel pump as a drive source, and forcibly pumps fuel outside the sub tank into the sub tank.
JP 2007-85251 A JP 2004-316567 A

  In the fuel supply device disclosed in Patent Document 1, when the two fuel pumps are driven when the engine needs a large amount of fuel (for example, during high-load operation), the fuel in the sub-tank suddenly increases. Decrease. In this case, fuel supply from the differential pressure valve provided at the bottom of the sub-tank is not in time, and there is a risk of causing a fuel supply failure.

  Therefore, as disclosed in Patent Document 2, it is conceivable that pumping means using a part of the fuel discharged from the fuel pump as a drive source is provided in the fuel supply device to forcibly pump the fuel into the sub tank. .

  However, simply providing the pumping means does not require a large amount of fuel, and when either one of the two fuel pumps is stopped, the fuel in the sub-tank rapidly decreases. Even in a situation where there is little fear, the fuel from the fuel pump is supplied to the pumping means, which causes a problem that the efficiency of the fuel supply device decreases.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a fuel supply device that can suppress a decrease in efficiency of the fuel supply device with a simple configuration.

The invention according to claim 1 is a fuel supply device that is installed in the fuel tank and supplies the fuel in the fuel tank to an external fuel consuming device, and a sub-tank that temporarily accumulates the fuel in the fuel tank; A first fuel pump that is housed in the sub-tank and is always driven during operation of the fuel consuming device, and a second fuel pump that is housed in the same sub- tank as the sub- tank that houses the first fuel pump and is driven as necessary. A part of the fuel discharged from the second fuel pump is used as a drive source, the pumping means for pumping the fuel in the fuel tank to the sub tank, and the fuel discharged from the first and second fuel pumps is supplied to the fuel consuming device. A first flow path having a merging portion for merging fuel discharged from the first and second fuel pumps in the middle of the flow path, and a branch between the discharge port and the merging portion of the second fuel pump From the department And provided in the middle of the first flow path between the second flow path for supplying fuel as a drive source to the pumping means, the merging section, and the branch section, and prevents fuel flow from the merging section side to the branch section side. And when the fuel consuming device requires a large amount of fuel, both the first and second fuel pumps are driven and the fuel consuming device requires less fuel than the large amount of fuel. When only the first fuel pump is driven, the first and second fuel pumps are accommodated, and a case having an upper end surface for allowing the fuel discharged from the discharge ports of the first and second fuel pumps to flow upward And, by covering the upper end surface from above, a space is formed between the upper end surface so that the fuel discharged from each discharge port of the first and second fuel pumps flowing out from the upper end surface flows in, And a cover that forms a confluence of the first flow path in the space. It is characterized in that it comprises.

  According to this invention, since the check valve for preventing the flow of fuel from the merging portion side to the branching portion side is provided between the merging portion and the branching portion in the first flow path, the second fuel pump is stopped. At this time, it is possible to suppress a decrease in the efficiency of the fuel supply device due to the fuel discharged from the first fuel pump flowing back to the second fuel pump and the pumping means.

  According to the present invention, the pumping means is driven only when the second fuel pump is being driven. The pumping means stops in a state where only the first fuel pump is driven, that is, in a state where the amount of fuel removed from the sub tank is small and it is not necessary to forcibly pump the fuel into the sub tank, the first and second fuel pumps Driving is performed in a driving state, that is, in a state where the amount of fuel taken away from the sub tank is large and it is necessary to forcibly pump up the fuel into the sub tank. Therefore, according to this configuration, it is possible to suppress a decrease in the efficiency of the fuel supply device due to the pumping means being driven at an unnecessary time.

  Therefore, according to the present invention, it is possible to suppress a reduction in efficiency of the fuel supply device including a plurality of fuel pumps with a simple configuration.

  The invention according to claim 2 is characterized in that a throttle is provided in the second flow path.

  According to this invention, since the throttle is provided in the second flow path, the amount of fuel supplied to the pumping means out of the fuel discharged from the second fuel pump can be reduced. Therefore, it is possible to suppress the supply of fuel exceeding the pumping performance required for the pumping means to the pumping means. As a result, it is possible to suppress a decrease in efficiency of the fuel supply device when the second fuel pump is driven. Further, since the throttle is provided in the second flow path, it is possible to suppress damage to the second flow path and the pumping means due to the fuel pressure discharged from the second fuel pump.

  The invention described in claim 3 is characterized in that a fuel filter for collecting foreign substances contained in the fuel is provided downstream of the junction.

  According to the present invention, since the fuel filter is provided on the downstream side of the merging portion, the fuel discharged from the first and second fuel pumps can be collected and filtered by one fuel filter. For this reason, it is not necessary to prepare a fuel filter for each fuel pump. As a result, the components housed in the sub tank are simplified, and the fuel supply device can be made compact.

  According to a fourth aspect of the present invention, the pumping means is provided at the opening formed at the bottom of the sub tank and at the end of the second flow path, and jets fuel from the outside of the opening toward the inside of the sub tank. And a jetting member.

  According to this invention, the pumping means is provided at the opening formed at the bottom of the sub tank and at the end of the second flow path, and the ejection member that ejects fuel from the outside of the opening toward the inside of the sub tank And. According to this, the fuel outside the sub tank is drawn by the fuel flow ejected from the ejection member and pumped into the sub tank from the opening. The fuel outside the sub tank can be pumped into the sub tank without using power other than the fuel flow discharged from the second fuel pump. For this reason, the enlargement of a fuel supply apparatus can be suppressed.

  Hereinafter, a fuel supply device according to the present invention will be described with reference to the drawings. The structure and operation of the fuel supply device 10 will be described with reference to FIGS.

  The fuel supply device 10 is installed, for example, in a fuel tank 12 that stores fuel consumed by an engine 11 as a fuel consuming device mounted on a vehicle. A part of the fuel supply device 10 is accommodated in the fuel tank 12. The fuel supply device 10 sucks up the fuel in the fuel tank 12 and discharges it toward the engine 11.

  First, the structure of the fuel supply device 10 will be described. The fuel supply device 10 includes a lid member 14, a sub tank 20, a pump module 30, and the like.

  FIG. 1 is a schematic view showing an outline of a fuel supply apparatus 10 according to the present invention. 2 to 4 are views showing a specific structure of the fuel supply device 10 shown in FIG. FIG. 2 is a side view showing only the lid member 14 and the pump module 30 in the fuel supply apparatus 10, and is a view seen from the II direction shown in FIG. FIG. 3 is a side view showing only the lid member 14 and the pump module 30 as in FIG. 2, and is a view seen from the III direction shown in FIG. 4. FIG. 4 is a top view of the pump module 30 and the sub tank 20 as seen from the IV direction illustrated in FIGS. 2 and 3. FIG. 5 is a cross-sectional view showing a characteristic portion of the present invention partially enlarged.

  As shown in FIGS. 1 to 4, the lid member 14 is formed in a disk shape with resin, and is attached so as to close the opening 13 formed in the top wall of the fuel tank 12. Other components of the fuel supply device 10 are accommodated in the fuel tank 12. The sub tank 20 is accommodated in the fuel tank 12, and the pump module 30 is accommodated in the sub tank 20 except for a part.

  A fuel discharge pipe 15 and electrical connectors 16a and 16b are integrally molded with the lid member 14 by resin. The fuel discharge pipe 15 is a pipe that supplies the fuel in the sub tank 20 discharged from the pump module 30 to the outside of the fuel tank 12. The electrical connectors 16a and 16b are electrically connected to power receiving connectors (not shown) provided in the main pump 31a and the sub pump 31b included in the pump module 30 by power feeding lines 17a and 17b and a power feeding connector (not shown). They are connected and supply power to both pumps 31a, 31b.

  As shown in FIGS. 1 and 4, the sub-tank 20 is a container that temporarily stores the fuel in the fuel tank 12 that is formed in a bottomed cylindrical shape that is open on the top wall side of the fuel tank 12. As shown in FIG. 1, the sub tank 20 accommodates most of the pump module 30.

  As shown in FIG. 4, an opening 22 that communicates the inside and outside of the sub tank 20 is formed at the bottom 21 of the sub tank 20. The opening 22 is provided with an open / close valve 23 that opens and closes due to the internal / external differential pressure of the sub tank 20.

  The on-off valve 23 opens when the pressure outside the sub tank 20 is higher than that inside the sub tank 20, and closes when the pressure outside the sub tank 20 is lower than inside. As a result, even if the pump module 30 sucks the fuel inside the sub tank 20 and supplies it to the engine 11 to reduce the liquid level inside the sub tank 20, the fuel is supplied to the outside of the sub tank 20 through the opening 22. More supplied. The fuel supplied to the inside of the sub tank 20 does not flow out of the sub tank 20 by the opening / closing valve 23.

  As shown in FIGS. 1 to 3, the pump module 30 is connected to the fuel discharge pipe 15 of the lid member 14 by a feed tube 36, sucks fuel inside the sub tank 20, and sets the fuel pressure to a predetermined pressure. And discharge toward the engine 11. The pump module 30 uses a part of the fuel sucked by the pump module 30 as a drive source, drives a jet pump 37 as a pumping means described later, and pumps fuel outside the sub tank 20 into the sub tank 20.

  The pump module 30 includes a main pump 31a, a sub pump 31b, a jet pump 37, a fuel filter 40, a pressure regulator 42, and the like. The main pump 31a, the sub pump 31b, and the fuel filter 40 are accommodated in the case 50 and the cover 70.

  As shown in FIGS. 2 and 3, a flange 51 is formed at the upper end of the case 50. The flange 51 is formed with a plurality of engaging portions 52 that engage with the upper end opening of the sub tank 20. With this configuration, the pump module 30 and the sub tank 20 are combined and integrated.

  As shown in FIGS. 2 and 3, a pipe support portion 53 that supports two support pipes 61 attached to the lid member 14 is provided on the side wall of the case 50. One end of each of these support pipes 61 is loosely inserted into each pipe support 53. Each of the support pipes 61 is provided with a spring 62 that urges the lid member 14 and the pump module 30 to be separated from each other between the pipe support portion 53 and the lid member 14.

  With these configurations, when the sub tank 20 and the pump module 30 are accommodated in the fuel tank 12 and the lid member 14 is attached to the opening 13 of the fuel tank 12, the sub tank 20 is pressed against the bottom of the fuel tank 12. Since the support pipe 61 is loosely inserted into the pipe support portion 53 and the support pipe 61 is provided with a spring 62, the resin fuel tank 12 expands and contracts due to a change in internal pressure or a change in fuel amount due to a temperature change. Even so, the bottom 21 of the sub-tank 20 is always pressed against the bottom of the fuel tank 12.

  The main pump 31a and the sub pump 31b have a motor as an electric drive unit (not shown) inside and a plurality of blades formed on the outer periphery, and have impellers 32a and 32b rotated by the motor. As the impellers 32a and 32b are rotated by a motor, both pumps 31a and 31b generate a fuel suction force.

  As shown in FIG. 1, the main pump 31a and the sub pump 31b have suction ports 33a and 33b formed at one end and discharge ports 34a and 34b formed at the other end, respectively. As the impellers 32a and 32b are rotated by the respective motors, a fuel suction force is generated in both the pumps 31a and 31b, and the fuel inside the sub tank 20 is sucked from the suction ports 33a and 33b. The fuel sucked into both the pumps 31a and 31b is discharged from the discharge ports 34a and 34b while being pressurized to a predetermined pressure. The discharge port 34a of the main pump 31a incorporates a check valve 35 that suppresses the backflow of fuel from the discharge port 34a to the suction port 33a (see FIG. 1).

  In the present embodiment, the main pump 31a is a pump that is always driven while the engine 11 is operating, and has a discharge capacity of 200 L / hour. On the other hand, the sub-pump 31b is a pump that is driven when a large amount of fuel needs to be consumed, for example, when the engine is started or accelerated, according to the operating state of the engine 11, and has a discharge capacity of 140L per hour.

  As shown in FIGS. 2 to 4, the main pump 31 a and the sub pump 31 b are arranged so that the axial direction of both pumps 31 a and 31 b in the case 50 and the axial direction of the case 50 formed in a cylindrical shape face the same direction. In the case 50. The suction ports 33a and 33b of both pumps 31a and 31b are directed toward the bottom 21 of the sub tank 20.

  A fuel inflow portion connected to the discharge ports 34a and 34b of both pumps 31a and 31b is formed at the upper end portion of the case 50. A fuel inflow portion (not shown) connected to the discharge port 34a of the main pump 31a extends to the upper end surface side of the case 50 and opens at the upper end surface. As shown in FIG. 5, the fuel inflow portion 54 connected to the discharge port 34 b of the sub pump 31 b does not open at the upper end surface of the case 50 and extends to the side wall side of the case 50. An end portion of the fuel inflow portion 54 is provided on a side wall portion of the case 50 and is connected to an intermediate portion 56 of a fuel passage portion 55 extending in the axial direction of the case 50. As shown in FIG. 5, the upper end portion of the fuel passage portion 55 is connected to an opening portion 57 formed on the upper end surface of the case 50. A check valve 58 is provided between the intermediate portion 56 and the opening 57. The check valve 58 is a valve that prevents fuel flow from the opening 57 side to the intermediate portion 56 side while allowing fuel flow from the intermediate portion 56 side to the opening 57 side. Therefore, only the fuel discharged from the sub pump 31b flows into the fuel passage portion 55 via the fuel inflow portion 54 (see FIG. 5).

  A cover 70 is attached to the upper end surface of the case 50. As shown in FIGS. 4 and 5, the cover 70 covers the fuel inflow portion on the main pump 31 a side and the opening 57 and also covers the inlet portion of the fuel filter 40 accommodated in the case 50. Yes. As a result, a space that communicates the fuel inflow portion on the main pump 31 a side, the opening 57 of the fuel passage portion 55, and the inlet portion of the fuel filter 40 is formed. In this space, a joining portion 71 is formed in which fuel discharged from both pumps 31a and 31b joins (see FIG. 4).

  As shown in FIG. 4, the fuel discharged from the main pump 31 a flows into the space through the fuel inflow portion and flows into the fuel filter 40. On the other hand, the fuel discharged from the sub pump 31b flows into the fuel passage portion 55 via the fuel inflow portion 54 as shown in FIG. Then, the fuel flows into the space from the opening 57 through the check valve 58 and flows into the fuel filter 40. The fuel path described above is shown as a flow path 73 in FIG. The merging portion 71 and the check valve 58 provided in the middle of the flow path 73 are the merging portion 71 and the check valve 58 shown in FIGS. 4 and 5. In this embodiment, the flow path from the flow path 73 shown in FIG. 1 to the fuel discharge pipe 15 via the fuel filter 40 corresponds to the first flow path described in the claims.

  As shown in FIGS. 3 and 5, an orifice member 59 having an orifice 60 therein is provided at the lower end portion of the fuel passage portion 55 so as to cover the lower end portion of the fuel passage portion 55. The orifice member 59 is connected to a tube 39 that guides the fuel that has passed through the orifice 60 to an ejection member 38 that forms a part of the jet pump 37. As shown in FIGS. 1 and 4, the ejection member 38 is attached to the outside of the sub tank 20 so as to eject fuel from the outside of the opening 22 of the sub tank 20 toward the inside of the sub tank 20.

  A part of the fuel discharged from the sub pump 31b is supplied to the ejection member 38. The fuel discharged from the sub pump 31 b is supplied to the ejection member 38 through the fuel inflow portion 54, the intermediate portion 56 of the fuel passage portion 55, the orifice 60 of the orifice member 59, and the tube 39. When the fuel is ejected from the ejection member 38, the fuel outside the sub tank 20 flows into the sub tank 20 through the opening 22 while being dragged by the flow of fuel ejected from the ejection member 38. In this way, the fuel outside the sub tank 20 is forcibly pumped into the sub tank 20. In this embodiment, since the jet pump 37 that pumps the fuel into the sub tank 20 is driven without using power other than the fuel flow discharged from the sub pump 31b, it is not necessary to prepare separately for driving the jet pump 37. . For this reason, the enlargement of the fuel supply apparatus 10 can be suppressed.

  The fuel path guided to the jet pump 37 is shown as a flow path 74 in FIG. This flow path 74 is branched from the flow path 73 described above. This branch portion is an intermediate portion 56 shown in FIG. In this embodiment, the flow path 74 shown in FIG. 1 corresponds to the second flow path described in the claims. Further, an intermediate portion 56 of the fuel passage portion 55 shown in FIG. 5 corresponds to a branch portion described in the claims.

  As shown in FIGS. 2 and 3, one bracket 72 that supports the lower ends of both pumps 31 a and 31 b is attached to the lower end of the case 50. This prevents both pumps 31a and 31b from falling out of the case 50.

  Suction filters 44a and 44b are attached to the tips of the respective suction ports 33a and 33b. The suction filters 44a and 44b collect relatively large foreign matters contained in the fuel sucked from the sub tank 20 by the two pumps 31a and 31b.

  The fuel filter 40 collects relatively small foreign matters contained in the fuel discharged from both the pumps 31a and 31b. In the present embodiment, the fuel filter 40 includes two cylindrical filter element portions 41a and 41b. As shown in FIG. 4, the filter element portions 41 a and 41 b are accommodated in the case 50 so that their axial directions are in the same direction as the axial direction of the case 50. The fuel discharged from both pumps 31a and 31b flows into these filter element portions 41a and 41b.

  As shown in FIG. 3, a feed tube 36 that guides the fuel flowing out from the fuel filter 40 to the fuel discharge pipe 15 is connected to the lower end portion of the case 50. A pressure regulator 42 is attached below the pressure regulator 42 for adjusting the pressure of the fuel discharged from both pumps 31a and 31b and flowing out of the fuel filter 40 to a predetermined pressure (see FIGS. 2 and 3). Excess fuel generated when the pressure regulator 42 adjusts the pressure of the fuel is discharged from a discharge port 43 provided in the pressure regulator 42. The discharge port 43 is accommodated in the sub tank 20.

  The fuel discharged from the main pump 31 a and the sub pump 31 b merges in a flow path 73 formed by the case 50 and the cover 70 and flows into the fuel filter 40. The fuel that has flowed out of the fuel filter 40 is guided to the fuel discharge pipe 15 through the feed tube 36 and discharged toward the engine 11.

  Next, the operation of the fuel supply device 10 will be described with reference to FIG. As described above, the fuel supply apparatus 10 includes the main pump 31a and the sub pump 31b. These pumps 31a and 31b are driven and controlled by a control device (not shown).

  For example, the control device determines that the engine 11 requires a large amount of fuel when the engine 11 is started or accelerated, and drives both pumps 31 a and 31 b to supply a large amount of fuel to the engine 11. Further, the control device determines that the engine 11 does not require a large amount of fuel during idle operation, low speed operation, constant speed operation, or low load operation, and supplies an appropriate amount of fuel to the engine 11. Only the main pump 31a is driven.

  Hereinafter, the operation of the fuel supply device 10 will be described separately when both the pumps 31a and 31b are driven and when only the main pump 31a is driven.

(Main pump 31a and sub pump 31b are driven)
When the main pump 31a and the sub pump 31b are driven, a fuel suction force is generated in both the pumps 31a and 31b, and the fuel in the sub tank 20 flows into the both pumps 31a and 31b through the suction filters 44a and 44b. The fuel flowing into both pumps 31a and 31b is pressurized by both pumps 31a and 31b and discharged from the discharge ports 34a and 34b. The fuel discharged from the discharge ports 34a and 34b flows into the fuel filter 40 through the flow path 73 (see FIG. 1).

  At this time, part of the fuel discharged from the discharge port 34 b of the sub pump 31 b flows into the ejection member 38 through the flow path 74 branched from the flow path 73. The fuel that has flowed into the ejection member 38 is ejected from the ejection member 38 toward the opening 22 of the sub tank 20, and fuel outside the sub tank 20 is pumped into the sub tank 20.

  The fuel that has passed through the fuel filter 40 is adjusted to a predetermined pressure by the pressure regulator 42 and flows into the fuel discharge pipe 15 through the feed tube 36. The fuel flowing into the fuel discharge pipe 15 is supplied to the engine 11 through the fuel pipe 18.

(Only the main pump 31a is driven)
When the main pump 31a is driven, a fuel suction force is generated only in the main pump 31a, and the fuel inside the sub tank 20 flows into the main pump 31a through the suction filter 44a. The fuel flowing into the main pump 31a is pressurized by the main pump 31a and discharged from the discharge port 34a. The fuel discharged from the discharge port 34 a flows into the fuel filter 40 through the flow path 73. Since the check valve 58 is provided in the flow path 73, the fuel discharged from the discharge port 34 a does not flow into the sub pump 31 b and the ejection member 38.

  The fuel that has passed through the fuel filter 40 is adjusted to a predetermined pressure by the pressure regulator 42 and flows into the fuel discharge pipe 15 through the feed tube 36. The fuel flowing into the fuel discharge pipe 15 is supplied to the engine 11 through the fuel pipe 18.

  In this embodiment, as shown in FIGS. 1 and 5, a check is made between the merging portion 71 in the flow path 73 and a portion where the flow path 74 branches from the flow path 73 (intermediate portion 56 shown in FIG. 5). A valve 58 is provided. According to this feature, when the sub pump 31b is stopped, that is, when the amount of fuel carried away from the sub tank 20 is small, the fuel discharged from the main pump 31a flows back to the sub pump 31b or the jet pump 37. A decrease in efficiency can be suppressed.

  In this embodiment, the jet pump 37 is driven by a part of the fuel discharged from the sub pump 31b. The jet pump 37 stops in a state where only the main pump 31a is driven, that is, in a state where the amount of fuel removed from the sub tank 20 is small and it is not necessary to forcibly pump the fuel into the sub tank 20, and both pumps 31a and 31b are driven. In this state, that is, in a state where the amount of fuel taken away from the sub tank 20 is large and it is necessary to forcibly pump up the fuel into the sub tank 20, the driving is performed. According to this feature, it is possible to suppress a decrease in the efficiency of the fuel supply device due to the jet pump 37 being driven at an unnecessary time.

  Therefore, according to this feature, it is possible to suppress a decrease in efficiency of the fuel supply device 10 including a plurality of fuel pumps (main pump 31a and sub pump 31b).

  Further, in this embodiment, since the orifice 60 that restricts the amount of fuel discharged from the sub pump 31b is provided downstream of the intermediate portion 56, that is, in the middle of the flow path 74, the pumping performance that is required for the jet pump 37 is exceeded. Can be prevented from being supplied to the jet pump 37. As a result, it is possible to suppress a decrease in efficiency of the fuel supply device 10 when the sub pump 31b is driven. Furthermore, since the pressure applied to the tube 39 can be reduced, damage to the tube 39 and the jet pump 37 can be suppressed.

  In this embodiment, as shown in FIG. 1, since the fuel filter 40 is provided on the downstream side of the merging portion 71, the fuel discharged from both the pumps 31 a and 31 b is filtered by one fuel filter 40. be able to. For this reason, it is not necessary to prepare the fuel filter 40 for each pump. As a result, since the components accommodated in the sub tank 20 are simplified, the fuel supply apparatus 10 can be made compact.

It is the schematic which showed the outline of the fuel supply apparatus by one Embodiment of this invention. It is the side view which showed only the cover member and the pump module among the fuel supply apparatuses shown in FIG. 1, and is the side view seen from the II direction shown in FIG. It is the side view which showed only the cover member and the pump module among the fuel supply apparatus shown in FIG. 1, and is the side view seen from the III direction illustrated in FIG. FIG. 4 is a top view of the pump module and the sub tank as viewed from the IV direction illustrated in FIGS. 2 and 3. It is sectional drawing which expanded and showed the characteristic part in the fuel supply apparatus shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Fuel supply apparatus, 11 Engine, 12 Fuel tank, 14 Cover member, 15 Fuel discharge pipe, 20 Sub tank, 21 Bottom part, 22 Opening part, 23 On-off valve, 30 Pump module, 31a Main pump, 31b Sub pump, 32a, 32b Impeller 33a, 33b Suction port, 34a, 34b Discharge port, 36 Feed tube, 37 Jet pump (pumping means), 38 Jet member, 39 Tube, 40 Fuel filter, 41a, 41b Filter element part, 42 Pressure regulator, 44a, 44b Suction filter, 50 case, 54 Fuel inflow part, 55 Fuel passage part, 56 Intermediate part, 57 Opening part, 58 Check valve, 59 Orifice member, 60 Orifice, 70 Cover, 71 Junction part, 72 Bracket, 73 Flow path, 7 4 Channel

Claims (4)

A fuel supply device installed in a fuel tank and supplying fuel in the fuel tank to an external fuel consuming device,
A sub tank for temporarily accumulating fuel in the fuel tank;
A first fuel pump housed in the sub-tank and always driven during operation of the fuel consuming device;
A second fuel pump that is housed in the same subtank as the subtank that houses the first fuel pump, and is driven as necessary;
A pumping means for pumping fuel in the fuel tank to the sub-tank, using a part of the fuel discharged from the second fuel pump as a drive source;
A first flow path for supplying the fuel discharged from the first and second fuel pumps to the fuel consuming device, and a merging portion for joining the fuel discharged from the first and second fuel pumps in the middle of the flow path A first flow path having
A second flow path that branches from a branch portion between the discharge port of the second fuel pump and the merging portion and supplies fuel as a drive source to the pumping means;
A check valve that is provided in the middle of the first flow path between the merging portion and the branching portion, and prevents a fuel flow from the merging portion side to the branching portion side;
Equipped with a,
When the fuel consuming device requires a large amount of fuel, both the first and second fuel pumps are driven, and when the fuel consuming device requires less fuel than the large amount of fuel, the first Only the fuel pump is driven,
A case having an upper end surface for containing the first and second fuel pumps and allowing the fuel discharged from the discharge ports of the first and second fuel pumps to flow upward;
By covering the upper end surface from above, a space in which the fuel discharged from the discharge ports of the first and second fuel pumps flowing out from the upper end surface flows in between the upper end surface. And a cover for forming the joining portion of the first flow path in the space .   The fuel supply device according to claim 1, wherein a throttle is provided in the second flow path.   3. The fuel supply device according to claim 1, wherein a fuel filter that collects foreign matters contained in the fuel is provided downstream of the merging portion. 4.   The pumping means includes an opening formed at the bottom of the sub tank, and an ejection member that is provided at an end of the second flow path and ejects fuel from the outside of the opening toward the inside of the sub tank. The fuel supply device according to any one of claims 1 to 3, wherein the fuel supply device is provided.

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