JP2021050716A - Fuel supply device of engine - Google Patents

Abstract

To provide a fuel supply device of an engine capable of securing safety against collision while improving workability.SOLUTION: A fuel supply device of an engine including a fuel pump 33 disposed on a rear part of a left side wall portion of the engine 1 in which a cylinder arrangement direction is determined in a vehicle body longitudinal direction, further has: suction piping 60 extended in a longitudinal direction, connected to a suction side of the fuel pump 33 at one end portion, and connectable to a prescribed external negative pressure source at the other end portion, the suction piping 60 capable of being closed by a cap 63 at the other end portion; and a check valve 70 disposed on the middle of the suction piping 60 for allowing fuel flow to a suction direction by the external negative pressure source and allowing and limiting the fuel flow to an anti-suction direction. The check valve 70 has a throttle passage 73 for allowing the fuel flow to the anti-suction direction.SELECTED DRAWING: Figure 4

Description

The present invention relates to a fuel supply device for an engine provided with a fuel pump on the rear side portion of the side wall portion on one side in the vehicle width direction of the engine in which the cylinder arrangement direction is set in the front-rear direction of the vehicle body.

Conventionally, a common rail that accumulates high-pressure fuel corresponding to the fuel injection pressure, a plurality of injectors that inject and supply the high-pressure fuel accumulated in the common rail to the combustion chamber of each cylinder of the engine, and fuel sucked from the fuel tank. A pressure-accumulation fuel injection device including a high-pressure fuel pump that increases the pressure and pumps the fuel to a common rail is known (for example, Patent Document 1).

Since the fuel tank is located below the rear floor panel, the fuel supply pipe connected to the fuel pump mounted on the side wall of the upper part of the engine arranged at the front of the vehicle body extends vertically and extends in the front-rear direction. The front and rear extension parts that extend to the front and rear are formed, and the length is increased.
If the capacity of the low-pressure feed pump for pumping fuel from the fuel tank to the fuel pump is small, or if the vehicle does not have the low-pressure feed pump itself, the fuel supply that connects the fuel tank and the fuel pump after the assembly process is completed. There is no fuel in the pipe.
Therefore, when the engine of a completed vehicle is started for the first time, it takes a long time from the start operation of the engine to the actual start (operation) of the engine, which causes a decrease in production efficiency.

Therefore, as shown in FIG. 13A, a suction pipe 104 branched from the middle portion of the fuel supply pipe 103 is newly formed in the fuel supply pipe 103 connecting the fuel tank 101 and the fuel pump 102. After the assembly process is completed, as shown in FIG. 13B, the tip of the suction pipe 104 is connected to the negative pressure equipment 105 of the factory, and fuel is forcibly sucked from the fuel tank 101 to a position near the fuel pump 102. .. As shown in FIG. 13C, after closing the tip of the suction pipe 104 with the lid member 106, the engine 100 is started.
As a result, it is possible to shorten the time required for the engine to start starting even when the engine is started for the first time after the assembly process is completed.

By the way, when the in-line multi-cylinder engine is mounted in the engine room at the front of the vehicle body, the engine may be arranged vertically so that the cylinder arrangement direction is directed to the front-rear direction.
Such a longitudinal engine has the points that it is easy to balance the left and right weights without concentrating the power mechanism on the front shaft, the left and right lengths of the drive shafts are even, and torque steer is difficult to occur, and the power plant including the engine. Since it has advantages such as easy processing of vibration and rocking, it tends to be adopted especially when mounting a large engine.

Japanese Unexamined Patent Publication No. 2010-112228

When the high-pressure fuel pump as described above is installed in a vertically installed engine, the fuel pump is arranged on the rear side of the side wall of the engine to supply fuel that connects the fuel tank located at the rear of the vehicle body to the fuel pump. The pipe can be shortened, the pressure loss of the fuel flowing in the fuel supply pipe can be reduced during fuel pumping, and the safety of the fuel pump in the event of a collision is ensured.
Further, when the fuel pump is arranged on the rear side portion of the side wall portion of the engine, the suction pipe for fuel suction extends to the front end portion of the engine. As a result, the workability of mounting the lid member can be improved, and in the event of a vehicle collision, the lid member can be dropped and the fuel can be returned to the fuel tank.
However, even the above configuration is not sufficient from the viewpoint of achieving both workability and collision safety.

When attaching the lid member to the tip of the suction pipe, the operator disconnects the connection between the tip of the suction pipe and the negative pressure equipment of the factory, and then attaches the lid member to the tip of the suction pipe.
Therefore, during the period from when the negative pressure equipment is disconnected until the lid member is attached to the tip of the suction pipe, the tip of the suction pipe is opened to the atmosphere, so that the fuel sucked by the negative pressure is released. There is a risk that the engine will flow back into the fuel tank and the engine start time cannot be shortened.

It is also conceivable to dispose a check valve (one-sided valve) in the middle of the suction pipe, which allows fuel flow in the suction direction and regulates fuel flow in the anti-suction direction.
However, if the check valve is installed on the front side (suction side) of the suction pipe, the check valve itself will be damaged in the event of a vehicle collision, and other equipment will be damaged due to interference with the retracted check valve. There is a risk of receiving. On the contrary, when the check valve is installed on the rear side (anti-suction side) of the suction pipe, a large amount of fuel stays in the pipe on the suction direction side (downstream side) of the check valve after the lid member is attached. Therefore, in the event of a vehicle collision, the fuel accumulated in the suction pipe may leak to the outside due to the damage of the suction pipe.
That is, it is not easy to achieve both workability and safety.

An object of the present invention is to provide an engine fuel supply device or the like capable of ensuring collision safety while improving workability.

The fuel supply device for the engine according to claim 1 is a fuel supply device for an engine having a fuel pump on the rear side portion on one side wall portion in the vehicle width direction of the engine in which the cylinder arrangement direction is set to the vehicle body front-rear direction. A piping member that extends in the direction, one end is connected to the suction side of the fuel pump, and the other end is connectable to a predetermined external negative pressure source, and the other end can be closed by a lid member. The check valve is provided in the middle of the piping member with a check valve that allows fuel flow in the suction direction by the external negative pressure source and also allows and limits fuel flow in the anti-suction direction. Is characterized by having a throttle passage for allowing fuel flow in the anti-suction direction.

In the fuel supply device of this engine, one end is a piping member that extends in the front-rear direction of the vehicle body and one end is connected to the suction side of the fuel pump, and the other end is a piping member that can be connected to a predetermined external negative pressure source. Since the part has a piping member that can be closed by the lid member, even if the capacity of the low pressure feed pump is small or the vehicle does not have the low pressure feed pump itself, after the engine is started and operated for the first time after the assembly process is completed. The time required to actually start the engine can be shortened, and the production efficiency can be improved.
Since the piping member has a check valve in the middle of the piping member that allows fuel flow in the suction direction by the external negative pressure source and also allows and limits fuel flow in the anti-suction direction, it is necessary to attach the lid member. Even if the tip of the piping member is opened to the atmosphere, the backflow of fuel sucked to the downstream side of the check valve can be suppressed.
Further, since the check valve has a throttle passage for allowing fuel flow in the anti-suction direction, the check valve is arranged at an upstream position (rear position) away from the tip of the piping member. However, the fuel staying in the piping member can be returned to the fuel tank side through the throttle passage, and fuel leakage at the time of a vehicle collision can be avoided.

According to a second aspect of the present invention, in the first aspect of the present invention, the throttle passage is a fuel whose absolute value of the return speed of the fuel when the external negative pressure source is not sucked is at least at least when the external negative pressure source is sucked. It is characterized in that it is configured to be smaller than the absolute value of the suction speed.
According to this configuration, the backflow tendency of the fuel sucked by the external negative pressure source can be controlled based on the flow rate of the fuel, and the mounting time of the lid member can be surely secured.

The invention of claim 3 is the invention of claim 1 or 2, wherein the check valve has a closing member that can move in the suction direction by fuel flow when the external negative pressure source sucks, and the external negative pressure source. The closing member is seated and has a seating portion that limits the flow of fuel in the anti-suction direction when the fuel is not sucked, and the throttle passage is provided in the seating portion.
According to this configuration, the check valve can be configured with a small number of parts.

According to a fourth aspect of the present invention, when the closing member is formed in a spherical shape, the seating portion has a substantially rectangular opening, and the closing member is seated in the opening, the opening. It is characterized in that the throttle passages are formed at the four corners of the portion.
According to this configuration, the throttle passage can be configured with a simple structure, and the formability of the check valve by the molding die can be improved.

The invention of claim 5 is characterized in that, in the invention of claim 3 or 4, the closing member is a steel ball and the seating portion is a synthetic resin.
According to this configuration, it is possible to achieve both weight reduction and moldability while ensuring the reliability of the check valve.

The invention of claim 6 is the invention of any one of claims 1 to 5, wherein the piping member has a vertical portion extending in the vertical direction in the middle portion, and the check valve is arranged in the vertical portion. It is characterized by being installed.
According to this configuration, the backflow tendency of the fuel sucked by the external negative pressure source can be controlled by using the own weight of the check valve.

The invention of claim 7 is characterized in that, in the invention of claim 6, the vertical portion is made of a flexible material.
According to this configuration, it is possible to prevent the check valve from being damaged in the event of a vehicle collision while improving the ease of mounting the check valve.

According to the fuel supply device of the engine of the present invention, collision safety can be ensured while improving workability by suppressing the backflow tendency of fuel after negative pressure suction.

It is an overall block diagram of the vehicle which concerns on Example 1. FIG. It is a bottom view of a vehicle. It is a side view. It is a side view of the main part of an engine. It is a figure which shows the hose of a suction pipe. It is the figure which looked at the check valve from above. It is a side view of the check valve. It is the figure which looked at the check valve from the bottom. FIG. 8 is a sectional view taken along line IX-IX of FIG. FIG. 8 is a cross-sectional view taken along the line X-X of FIG. It is a figure corresponding to FIG. 10 which concerns on the modification of the check valve. It is a partial vertical sectional view of the outer cylinder member. It is a figure explaining the procedure from fuel suction to mounting a lid member.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The following description exemplifies the application of the present invention to a hybrid vehicle, and does not limit the present invention, its application, or its use.

Hereinafter, Example 1 of the present invention will be described with reference to FIGS. 1 to 10.
First, the overall configuration of the vehicle V to which the fuel supply device for the engine according to the present invention is applied will be described with reference to FIG.
As shown in FIG. 1, the vehicle V has, for example, an in-line 6-cylinder diesel engine 1 as a first power source and a motor generator as a second power source arranged at a position on the downstream side of the engine 1 (hereinafter referred to as a motor generator). (Abbreviated as motor) 2, an automatic transmission (hereinafter abbreviated as AT) 3 arranged at a position downstream of the motor 2, and a differential that distributes driving force to a pair of left and right rear wheels 8. It is a hybrid vehicle including a gear mechanism (hereinafter, abbreviated as a differential mechanism) 4, a power supply mechanism E, a fuel supply mechanism F, and the like.

The engine 1 is vertically arranged in an engine room formed in the front portion of the vehicle body so that the cylinder arrangement direction is along the front-rear direction of the vehicle body, and is driven by using light oil supplied from the fuel supply mechanism F as a power source. The output shaft of the engine 1 is arranged so as to correspond to the front position (front) of the tunnel portion 9a formed on the floor panel 9 described later. The output shaft of the engine 1 and the rotating shaft of the motor 2 are connected via an intermittent first clutch 5.
Hereinafter, the arrow F direction will be described as forward, the arrow L direction as left, and the arrow U direction as upward.

The motor 2 is, for example, a 25 kW permanent magnet electric motor driven by 48 V.
As shown in FIGS. 2 and 3, the motor 2 is coaxially and serially connected to the rear end portion of the engine 1 between the tunnel portion 9a and the suspension cross 12.
The motor 2 is driven by using the electric power supplied from the electric power supply mechanism E as a power source. The rotating shaft of the motor 2 and the rotating shaft of the AT3 are connected via an intermittent second clutch 6.
AT3 is substantially housed in the tunnel portion 9a. The differential mechanism 4 is configured such that the driving force is input via the output shaft of the AT3 and the driving force distribution ratio to the drive shaft 7 corresponding to each of the left and right rear wheels 8 can be changed according to the steering state.

Next, the power supply mechanism E will be described.
As shown in FIGS. 1 to 3, the power supply mechanism E includes a battery 21, an inverter 22 electrically connected to the battery, and a DC / DC converter 23 electrically connected to the inverter 22. A terminal block 24 electrically connected to the motor 2 and a high-voltage harness 25 or the like electrically connected to the inverter 22 and the terminal block 24 are provided.

The battery 21 is a capacitor for storing electric power for operating the motor 2.
As the battery 21, for example, a 48 V, 3.5 kWh lithium ion battery is used, and is appropriately arranged inside the tunnel portion 9a.
The inverter 22 is configured to convert the direct current of the battery 21 into alternating current and supply the converted alternating current to the motor 2 via the harness 25 and the terminal block 24.
The converter 23 is configured to step down the 48V electric power stored in the battery 21 to 12V and supply it to the 12V-operable electrical equipment mounted on the vehicle V.
The terminal block 24 distributes the electric power supplied from the inverter 22 to the motor 2.

Next, the fuel supply mechanism F will be described.
The fuel supply mechanism F includes a flat fuel tank 31 capable of storing light oil as fuel, a fuel filter 32 connected to the fuel tank 31 via a first fuel supply pipe 34, and a fuel filter 32 connected to the fuel filter 32. 2 A fuel pump 33 connected via a fuel supply pipe 35 and connected to a pair of front and rear common rails 54a and 54b extending forward and backward via a third fuel supply pipe 36a and 36b, and surplus fuel to the fuel tank 31. The main constituent elements are the fuel recirculation pipe 37 and the like to be conveyed. As shown in FIGS. 2 and 3, the fuel tank 31 is below the rear end side portion of the floor panel 9, specifically, below the kick-up portion formed in a rearward upward inclination at the rear portion of the floor panel 9. It is suspended and fixed by a pair of left and right fixing belts 13.

As shown in FIGS. 3 and 4, the fuel pump 33 is fastened and fixed to the left side wall portion of the engine 1 via bolts. Specifically, it is mounted on the lower side of the intake manifold 53 of the cylinders in the last row and in the middle stage of the cylinder block 51. The fuel pump 33 integrally has a low-pressure pump function and a high-pressure pump function. The low-pressure pump function transfers fuel from the fuel tank 31 to the fuel pump 33 via the first and second fuel supply pipes 34 and 35, and the high-pressure pump function transfers fuel from the fuel pump 33 to the pair of common rails 54a and 54b. 3 Fuel is pumped through the fuel supply pipes 36a and 36b.

The fuel pump 33 is a dual pump, and is a first high-pressure pump unit that supplies fuel to a low-pressure feed pump (not shown) and an injector (not shown) mounted on the front three cylinders via a common rail 54a. It includes 33a and a second high-pressure pump unit 33b that supplies fuel to injectors mounted on the rear three cylinders via a common rail 54b.
The surplus fuel of the fuel pump 33 is sent to the return collecting unit 39 via the pump return pipe 38.

As shown in FIG. 4, the surplus fuel of the common rails 54a and 54b is collected in a single common rail return pipe 40 and sent to the return collecting unit 39. Similarly, the surplus fuel of each injector is collected in a single injector return pipe 41 and sent to the return collecting unit 39. The fuel pump 33, the common rails 54a and 54b, and the surplus fuel of each injector are collected in the return collecting portion 39 and then returned to the fuel tank 31 by the fuel return pipe 37.

As shown in FIG. 4, the second fuel supply pipe 35 has a substantially U-shape, that is, the so-called intermediate portion is once raised to a position higher than the upper top portion of the first high-pressure pump portion 33a and to a position near the lower end of the intake manifold 53. After that, it descends and is connected to a portion corresponding to a suction portion (not shown) of the low pressure feed pump formed in the middle portion of the fuel pump 33. Further, the fuel return pipe 37 has a substantially U-shape, that is, the intermediate portion on the downstream side of the so-called return collecting portion 39 is higher than the upper top portion of the first high-pressure pump portion 33a, and the fuel return pipe 37 is once reached a position near the lower end of the intake manifold 53. After ascending, it descends to the position of the lower end of the cylinder block 51. By this. Increase the amount of fuel that is held without backflow in the region from the fuel pump 33 to the top of the second fuel supply pipe 35, and the fuel that is held without returning to the region from the fuel pump 33 to the top of the fuel return pipe 37. Is increasing.

A suction pipe 60 (piping member) is connected to the middle stage of the second fuel supply pipe 35.
When the engine 1 of the completed vehicle V is started after the vehicle assembly process is completed, the first and second fuel supply pipes 34 and 35 are not yet filled with fuel, so that even if the fuel pump 33 starts operating, It takes a considerable amount of time for the engine 1 to actually start operation (fuel reaches the fuel pump 33). Therefore, a negative pressure source (hereinafter referred to as an external negative pressure source) provided as a factory facility is connected to a suction pipe 60 connected to the second fuel supply pipe 35, and the fuel is fueled by the external negative pressure source. Suction is performed from the tank 31 to a position near the fuel pump 33.
After the initial suction is completed, the suction pipe 60 and the external negative pressure source are separated, the opening of the suction pipe 60 is closed by the removable cap 63 (lid member), and the engine 1 is started.

As shown in FIG. 4, the suction pipe 60 includes a hose 61 (vertical portion), a pipe 62 having one end connected to the hose 61, a synthetic resin cap 63 for closing the pipe 62, and the like. The hose 61 is molded from an elastic flexible material, such as rubber, with the upper half formed in a substantially U-shape protruding rearward to avoid interference with peripheral components, and the lower half up and down. It is formed vertically so as to extend. The lower end portion corresponding to one end portion of the hose 61 is connected to the middle portion of the second fuel supply pipe 35 in the lower near region of the return collecting portion 39. The upper end corresponding to the other end of the hose 61 is connected to the rear end of the pipe 62.

The pipe 62 is formed of metal, extends forward from the rear end corresponding to one end, and then bends upward through a gap between the left wall of the engine 1 and the intake manifold 53 to form a vertical shape. It is erected in. The upper end corresponding to the other end of the pipe 62 is arranged near the front and above the front common rail 54a fixed to the cylinder head 52.

As shown in FIG. 5, a check valve 70 is fitted in the vertical lower half of the hose 61.
The check valve 70 allows the fuel to flow upward (in the suction direction) and downward (in the anti-suction direction) when the external negative pressure source is connected to the upper end of the suction pipe 60. It is configured to limit. As a result, the fuel sucked by the negative pressure is lowered to the fuel tank 31 from the time when the operator disconnects the external negative pressure source until the cap 63 is attached to the upper end of the pipe 62. It prevents backflow.

The check valve 70 mainly includes a cylindrical outer cylinder member 71 and a steel ball 72 (closing member) housed in the outer cylinder member 71 so as to be vertically movable. As shown in FIGS. 6 to 10, the synthetic resin outer cylinder member 71 includes a seating portion 71a, an annular portion 71b, a pair of first side wall portions 71c facing each other, and a pair of first side wall portions 71c facing each other. It is provided with two side wall portions 71d and the like. The fuel is introduced from the seating portion 71a and led out from the annular portion 71b when sucked by the external negative pressure source.

The seating portion 71a is arranged so as to be at the lowermost portion, and has a square opening 71e.
Since the size of one side of the opening 71e is set to be shorter than the diameter of the steel ball 72, when the steel ball 72 is seated on the seating portion 71a (opening 71e), the four openings 71e The corners (four corners) and the steel ball 72 are separated from each other. That is, each corner of the opening 71e forms the throttle passage 73.

In the throttle passage 73, when the steel ball 72 is seated on the seating portion 71a (when the external negative pressure source does not suck), the absolute value of the fuel return speed is at least when the steel ball 72 is not seated on the seating portion 71a (external negative). It is configured to be less than the absolute value of the fuel suction rate (when the pressure source sucks). In this embodiment, the fuel return speed is set to be, for example, 4 cc / sec. As a result, even if the working time from the separation of the external negative pressure source and the pipe 62 to the closure of the pipe 62 by the cap 63 is prolonged after the fuel is sucked by the external negative pressure source, the backflow of the fuel can be suppressed and the fuel can be suppressed. The liquid level of the above is kept near the connection portion between the hose 61 and the second fuel supply pipe 35.

The pair of first side wall portions 71c connects the seating portion 71a and the annular portion 71b, respectively.
A pair of second side wall portions 71d are erected upward from the seating portion 71a toward the annular portion 71b, respectively. A locking portion 71f protruding inward is formed at the tip end portion (upper end portion) of the second side wall portion 71d. When the steel ball 72 is sucked by the external negative pressure source, the steel ball 72 moves upward with the flow of fuel, and when locked with the locking portion 71f, the steel ball 72 stops the upward movement.

Next, the operation and effect of the fuel supply device of the engine according to the embodiment of the present invention will be described.
According to the present embodiment, the suction pipe 60 extends back and forth, one end is connected to the suction side of the fuel pump 33, and the other end is connectable to a predetermined external negative pressure source, and the other end is a cap. Since the vehicle V has a suction pipe 60 that can be closed by 63, the capacity of the low-pressure feed pump is small, or even if the vehicle V does not have the low-pressure feed pump itself, after the engine 1 is started and operated for the first time after the assembly process is completed. The time required for the engine 1 to actually start starting can be shortened, and the production efficiency can be improved.
Since the check valve 70 is provided in the middle of the suction pipe 60 to allow the fuel flow in the suction direction by the external negative pressure source and to allow and limit the fuel flow in the non-suction direction, the cap 63 is attached. Even if the tip of the suction pipe 60 is opened to the atmosphere, the backflow of fuel sucked to the downstream side of the check valve 70 can be suppressed.
Further, since the check valve 70 has a throttle passage 73 for allowing fuel flow in the anti-suction direction, even if the check valve 70 is arranged at a rear position away from the tip of the suction pipe 60, it may be arranged. The fuel staying in the suction pipe 60 can be returned to the fuel tank 31 side through the throttle passage 73, and fuel leakage at the time of a vehicle collision can be avoided.

The throttle passage 73 is configured so that the absolute value of the fuel return speed when the external negative pressure source does not suck is at least smaller than the absolute value of the fuel suction speed when the external negative pressure source sucks. The backflow tendency of the fuel sucked by the negative pressure source can be controlled based on the flow rate of the fuel, and the wearing time of the cap 63 can be surely secured.

The check valve 70 has a steel ball 72 that can move in the suction direction due to fuel flow when the external negative pressure source sucks, and a steel ball 72 that sits in the anti-suction direction when the external negative pressure source does not suck. Since the throttle passage 73 is provided in the seating portion 71a and has a seating portion 71a that limits the fuel flow, the check valve 70 can be configured with a small number of parts.

The steel ball 72 is formed in a spherical shape, the seating portion 71a is provided with a substantially rectangular opening 71e, and when the steel ball 72 is seated in the opening 71e, the throttle passages 73 are formed at the four corners of the opening 71e. The passage 73 can be configured with a simple structure, and the formability of the check valve 70 by the molding die can be improved.

Since the steel ball 72 is a steel ball and the seating portion 71a is a synthetic resin, it is possible to achieve both weight reduction and moldability while ensuring the reliability of the check valve 70.

Since the suction pipe 60 has a hose 61 extending in the vertical direction in the middle and the check valve 70 is arranged in the hose 61, the backflow tendency of the fuel sucked by the external negative pressure source is caused by the own weight of the steel ball 72. Can be controlled using.

Since the hose 61 is made of a flexible material, it is possible to improve the ease of mounting the check valve 70 and prevent the check valve 70 from being damaged in the event of a vehicle collision.

Next, a modified example in which the embodiment is partially modified will be described.
1] In the above embodiment, an example of a 6-cylinder diesel longitudinal engine has been described, but the engine type, number of cylinders, model, arrangement form, etc. can be arbitrarily set. For example, a 4-cylinder gasoline engine. It may be. Further, although an example of a hybrid vehicle has been described, it is not limited to a hybrid vehicle as long as it is a vehicle equipped with at least an engine, a fuel tank and a fuel filter.

2] In the above embodiment, an example in which the throttle passage 73 of the check valve 70 is integrally configured with the fuel introduction opening by using the four corners of the opening 71e formed in the seating portion 71a has been described. The 73A may be configured separately from the fuel introduction opening.
As shown in FIGS. 11 and 12, the check valve 70A mainly includes a cylindrical outer cylinder member 71A and a steel ball 72 housed in the outer cylinder member 71A so as to be vertically movable.
The outer cylinder member 71 includes a seating portion 71s, an annular portion 71b, a pair of first side wall portions 71c, a pair of second side wall portions 71d, and the like. The same members as those in the first embodiment are designated by the same reference numerals.

The seating portion 71s is arranged so as to be at the lowermost portion, and has a circular introduction opening 71t. The diameter of the introduction opening 71t is set to be shorter than the diameter of the steel ball 72.
A pair of throttle passages 73A are formed in the seating portion 71s so as to face each other.
The throttle passage 73A constitutes a groove recessed outward in the radial direction from the introduction opening 71t. By changing the width and depth of the throttle passage 73A, the return speed when the steel ball 72 is seated on the seating portion 71s is adjusted.

3] In the above embodiment, an example in which the throttle passage 73 of the check valve 70 is integrally configured with the fuel introduction opening by using the four corners of the square opening 71e formed in the seating portion 71a has been described. At least, it suffices if the aperture passage can be formed at the corners, and the same effect can be obtained if the shape is a regular polygon.

4] In addition, a person skilled in the art can carry out the present invention in a form in which various modifications are added to the above-described embodiment or in a combination of the respective embodiments without deviating from the gist of the present invention. It also includes various modified forms.

1 Engine 33 Fuel pump 60 Suction pipe 61 Hose 63 Cap 70, 70A Check valve 71a, 71s Seating part 71e Opening 72 Steel ball 73, 73A Squeezing passage

Claims (7)

In an engine fuel supply device equipped with a fuel pump on the rear side of the side wall on one side in the vehicle width direction in which the cylinder arrangement direction is set to the front-rear direction of the vehicle body.
A piping member that extends in the front-rear direction of the vehicle body, has one end connected to the suction side of the fuel pump, and the other end can be connected to a predetermined external negative pressure source, and the other end can be closed by a lid member. Piping members and
A check valve is provided in the middle of the piping member to allow and limit fuel flow in the suction direction by the external negative pressure source and also to allow and limit fuel flow in the anti-suction direction.
The check valve is a fuel supply device for an engine, characterized in that it has a throttle passage for allowing fuel flow in the anti-suction direction. The throttle passage is configured such that the absolute value of the fuel return speed when the external negative pressure source does not suck is at least slower than the absolute value of the fuel suction speed when the external negative pressure source sucks. The fuel supply device for an engine according to claim 1. The check valve has a closing member that can move in the suction direction due to fuel flow when the external negative pressure source sucks, and a closing member that sits in the anti-suction direction when the external negative pressure source does not suck. Has a seating area that limits the fuel flow of the
The fuel supply device for an engine according to claim 1 or 2, wherein the throttle passage is provided in the seating portion. The closing member is formed in a spherical shape, the seating portion is provided with a substantially rectangular opening, and when the closing member is seated in the opening, the throttle passages are formed at the four corners of the opening. The fuel supply device for the engine according to claim 3. The fuel supply device for an engine according to claim 3 or 4, wherein the closing member is a steel ball and the seating portion is a synthetic resin. The piping member has a vertical portion extending in the vertical direction in the middle portion.
The fuel supply device for an engine according to any one of claims 1 to 5, wherein the check valve is arranged in the vertical portion. The fuel supply device for an engine according to claim 6, wherein the vertical portion is made of a flexible material.

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