JP2020169582A - Fuel supply device for engine - Google Patents

Abstract

To provide a fuel supply device for supplying different types of fuel to an engine, which improves the responsiveness of fuel supply from each injector.SOLUTION: A fuel supply device for an engine includes first injectors (31) connected to a first delivery pipe (30) for injecting first fuel to intake passages (21, 23), and a second injector (41) connected to a second delivery pipe (40) for injecting second fuel to the intake passages, the two first injector being arranged for one intake passage, the one second injector being arranged for one intake passage, the two first injectors having respective two first connectors (32) to which a first harness-side connector (33) is connected, positioned to face directions of separating from each other, the second injector being at least partly arranged in a space held between the two first connectors.SELECTED DRAWING: Figure 5

Description

The present invention relates to a fuel supply device capable of supplying different fuels to an engine.

Bi-fuel vehicles can switch the fuel supplied to the engine. As an example, a bi-fuel vehicle that can be used by switching between gasoline and compressed natural gas (hereinafter referred to as CNG) is known.

In such a bi-fuel vehicle, the fuel supply device of the engine is provided with two fuel supply systems, and the structure tends to be complicated. In particular, since the arrangement density of fuel supply system parts becomes high in the vicinity of the fuel injection device that injects each fuel into the intake passage, there is a demand to efficiently install the fuel injection device in a restricted space. Further, it is required to arrange the fuel injection device for injecting each fuel as close to the combustion chamber as possible to improve the responsiveness of the fuel supply.

Patent Document 1 describes a configuration in which at least a part of a CNG injector that injects CNG is arranged below a gasoline injector that injects gasoline in an engine for a bi-fuel vehicle.

Japanese Unexamined Patent Publication No. 2018-132046

In the engine of Patent Document 1, an injector for gasoline and an injector for CNG are arranged so as to be arranged along an intake passage for supplying air to a combustion chamber. Therefore, there is a restriction that the injector (injector for CNG) located on the side far from the combustion chamber is brought close to the combustion chamber. When the position of the injector is far from the combustion chamber, the timing difference until the fuel injected from the injector flows into the combustion chamber becomes large, and the responsiveness of the fuel supply deteriorates.

The present invention has been made in view of the above points, and an object of the present invention is to improve the responsiveness of fuel supply from an injector for fuel injection in a fuel supply device that supplies a first fuel and a second fuel to an engine. To do.

The present invention includes a first delivery pipe, a first fuel injection device having a plurality of first injectors connected to the first delivery pipe, and injecting the first fuel into an intake passage, and a first fuel injection device. A second fuel injection device having a second delivery pipe and a plurality of second injectors connected to the second delivery pipe to inject a second fuel into an intake passage, and an outer circumference of the first injector. A first connector that protrudes outward from the first harness side connector and a second connector that protrudes outward from the outer periphery of the second injector and connects the second harness side connector. In the fuel supply device of the engine including, the first injector is arranged in one intake passage, the second injector is arranged in one intake passage, and one injector is arranged in one intake passage. The corresponding two first injectors are positioned so that the two first connectors face away from each other, and the second injector is in a space that is at least partially sandwiched between the two first connectors. It is characterized by being arranged.

According to the present invention, each injector can be brought closer to the combustion chamber, and the responsiveness of the fuel supply from the injector is improved.

It is a top view of the engine of this embodiment. It is sectional drawing which follows the line II-II of FIG. It is a perspective view of a part of the engine with the delivery pipe removed, as seen along the arrow III of FIG. It is a perspective view of the state which removed the harness connected to each injector as seen along the arrow III of FIG. It is a perspective view of the state excluding the delivery pipe and the harness as seen along the arrow III of FIG.

Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. Each direction (front-back, left-right, up-down) in the following description means each direction in the vehicle with the engine 10 mounted on the vehicle.

The overall configuration of the engine 10 will be described with reference to FIGS. 1 and 2. As shown in FIG. 2, the engine 10 has a cylinder block 11, a cylinder head 12 located above the cylinder block 11, and a cylinder head cover 13 located above the cylinder head 12. Three cylinders 15 arranged in the left-right direction are formed in the cylinder block 11. That is, the engine 10 of the present embodiment is an in-line 3-cylinder engine. Hereinafter, the description will be made with reference to one cylinder shown in FIG. 2, but the remaining two cylinders have the same configuration.

Pistons 16 that can reciprocate in the vertical direction are arranged in the cylinders 15 that constitute each cylinder, and each piston 16 is connected to a crankshaft (not shown) via a connecting rod (not shown). When the piston 16 reciprocates, the crankshaft rotates.

A combustion chamber 20 communicating with the upper end of the cylinder 15 of each cylinder is formed in the cylinder head 12. An intake port 21 extends rearward from the combustion chamber 20. An intake manifold 22 is provided at the rear of the engine 10, and each of the three intake ports 21 connected to the three cylinders leads to an intake pipe 23 of the intake manifold 22. The intake port 21 and the intake pipe 23 form an intake passage, and the outside air taken in from the outside of the vehicle flows into the combustion chamber 20 through the intake pipe 23 and the intake port 21. As shown in FIG. 2, among the intake passages leading to each cylinder, the intake port 21 and a part of the intake pipe 23 connected to the intake port 21 extend substantially linearly in the front-rear direction.

An exhaust port 24 extends forward from the combustion chamber 20. Each of the three exhaust ports 24 connected to the three cylinders is connected to an exhaust pipe (not shown) of an exhaust manifold (not shown).

The engine 10 is an internal combustion engine for a bi-fuel vehicle that can be used by switching between different types of first fuel and second fuel. The present invention does not limit the type of fuel, but in the present embodiment, gasoline is used as the first fuel and CNG (compressed natural gas) is used as the second fuel. The fuel supply device in the engine 10 has two fuel supply systems, one for the first fuel and the other for the second fuel.

The fuel supply system for the first fuel supplies the first fuel from the first fuel tank (not shown) to the first delivery pipe 30 via the first fuel pipeline (not shown). The first delivery pipe 30 extends long in the left-right direction, and a plurality of first injectors 31 are connected to the first delivery pipe 30 at different positions in the longitudinal direction thereof. Two first injectors 31 are provided for each cylinder of the engine 10, and a total of six first injectors 31 are arranged along the longitudinal direction of the first delivery pipe 30 (FIGS. 1 and 3). 5).

A liquid first fuel (gasoline) is stored in the first fuel tank, and by driving a fuel pump (not shown), the first delivery pipe 30 passes from the first fuel tank through the first fuel pipeline. The first fuel is pumped up to. The tip of each first injector 31 is located at a position leading to the intake port 21 for the corresponding cylinder, and a drive signal for injection is sent from the engine ECU (not shown) that controls the engine 10 to each first injector 31. Then, the first fuel is injected from the first injector 31 into the intake port 21. Therefore, the first delivery pipe 30 and the first injector 31 constitute a first fuel injection device that injects the first fuel into the intake passage (intake port 21). The first fuel injected from each first injector 31 mixes with the air taken into the intake passage to generate an air-fuel mixture, and the air-fuel mixture enters the combustion chamber 20 with the opening of the intake valve 25 (FIG. 2). Inflow to.

The fuel supply system for the second fuel supplies the second fuel from the second fuel tank (not shown) to the second delivery pipe 40 via the second fuel pipeline (not shown). The second delivery pipe 40 extends long in the left-right direction, and a plurality of second injectors 41 are connected to the second delivery pipe 40 at different positions in the longitudinal direction thereof. One second injector 41 is provided for each cylinder of the engine 10, and a total of three second injectors 41 are arranged along the longitudinal direction of the second delivery pipe 40 (see FIGS. 3 to 5). ..

A gaseous second fuel (CNG) is stored in the second fuel tank in a high-pressure state, and when a normally closed electromagnetic valve (not shown) is energized and opened, the second fuel tank to the second fuel The second fuel is delivered to the second delivery pipe 40 via the pipeline. The tip of each second injector 41 is located at a position leading to the intake pipe 23 for the corresponding cylinder, and when a drive signal for injection is sent from the engine ECU to each second injector 41, the second injector 41 to the intake pipe 23 The second fuel is injected inside. Therefore, the second delivery pipe 40 and the second injector 41 constitute a second fuel injection device that injects the second fuel into the intake passage (intake pipe 23). The second fuel injected from each second injector 41 mixes with the air taken into the intake passage to generate an air-fuel mixture, and the air-fuel mixture enters the combustion chamber 20 with the opening of the intake valve 25 (FIG. 2). Inflow to.

As shown in FIG. 2, spark plugs 26 are provided so that electrodes are located in each combustion chamber 20. The engine ECU controls the ignition timing of the spark plug 26, and the ignition of the spark plug 26 ignites and burns the air-fuel mixture in the combustion chamber 20. Due to the combustion of the air-fuel mixture, the piston 16 reciprocates in the cylinder 15, the reciprocating motion of the piston 16 is converted into the rotational motion of the crankshaft, and is output as power by the engine 10. The exhaust gas after burning in the combustion chamber 20 enters the exhaust port 24 when the exhaust valve 27 is opened, and is discharged to the outside of the vehicle via the exhaust pipe.

The fuel used in the engine 10 is selected by the switching operation by the driver of the vehicle or the automatic switching by the control of the engine ECU. The engine ECU controls the injection amount and injection timing of the fuel selected for use among the first fuel and the second fuel. That is, in the state where the use of the first fuel is selected, the drive signal is sent from the engine ECU to the first injector 31, and the fuel injection from the first injector 31 is controlled. Further, in the state where the use of the second fuel is selected, the drive signal is sent from the engine ECU to the second injector 41, and the fuel injection from the second injector 41 is controlled.

As shown in FIGS. 3 to 5, each of the six first injectors 31 (31L, 31R) is provided with a first connector 32 projecting outward from the outer circumference. A connection terminal portion 32a (see FIGS. 4 and 5) is provided at the end of the first connector 32. A first harness-side connector 33 provided at one end of the first harness 34 is connected to the connection terminal portion 32a of each first connector 32 (see FIG. 3).

As shown in FIGS. 3 to 5, each of the three second injectors 41 (41A, 41B, 41C) is provided with a second connector 42 projecting outward from the outer circumference. A connection terminal portion 42a (see FIGS. 4 and 5) is provided at the end of the second connector 42. A second harness-side connector 43 provided at one end of the second harness 44 is connected to the connection terminal portion 42a of each second connector 42 (see FIG. 3).

Although not shown, the first harness 34 and the second harness 44 are connected to an input / output port (not shown) of the engine ECU, and an electric signal for operation is transmitted from the engine ECU via the first harness 34. It is sent to the 1 injector 31, and an electric signal for operation is sent from the engine ECU to the second injector 41 via the second harness 44.

The layout of the first fuel injection device and the second fuel injection device will be described below. As shown in FIGS. 1 and 2, the first delivery pipe 30 and the second delivery pipe 40 are located at substantially the same position in the vertical direction and are arranged in the front-rear direction (the first delivery pipe 30 is forward and first. 2 Delivery pipe 40 is located at the rear). Then, the first injector 31 extends diagonally forward and downward from the first delivery pipe 30, and the second injector 41 extends diagonally forward and downward from the second delivery pipe 40. When viewed sideways from the left-right direction as shown in FIG. 2, the directions in which the first injector 31 and the second injector 41 extend are substantially parallel. The positional relationship of each part of the fuel injection device when viewed along the central axis of the first injector 31 and the second injector 41 (along the arrow III of FIG. 2) is shown in FIGS. 3 to 5.

FIG. 5 shows three virtual planes PA, PB, and PC extending in the front-rear direction through the central axes of the three second injectors 41. These three planes PA, PB, and PC are generally located on the center lines of the three intake ports 21. Of the three second injectors 41, the one located on the plane PA is referred to as the second injector 41A, the one located on the plane PB is referred to as the second injector 41B, and the one located on the plane PC is referred to as the second injector 41C. ..

Two first injectors 31 provided for each cylinder are arranged side by side in the left-right direction so as to sandwich the center line of each intake port 21. Of the two first injectors 31 for each cylinder, the one located on the left side is referred to as the first injector 31L, and the one located on the right side is referred to as the first injector 31R.

As shown in FIG. 5, the first injector 31L and the first injector 31R, which are paired on the left and right, are arranged substantially symmetrically on both sides of the plane PA, the plane PB, and the plane PC. Then, as the first injector 31L and the first injector 31R proceed rearward (in the direction away from the combustion chamber 20) along the intake passage, the two first connectors 32 face in the direction away from each other (two first connectors 32). It is positioned so that the interval between the two is large). That is, the first connector 32 of the first injector 31L and the first connector 32 of the first injector 31R are oriented so as to move away from the center line (plane PA, PB, PC) of the intake port 21 as they advance toward the tip side. Has been done. Then, in the first connector 32 of the first injector 31L, the connection terminal portion 32a faces diagonally rearward to the left, and in the first connector 32 of the first injector 31R, the connection terminal portion 32a faces diagonally rearward to the right. Each of the first injector 31L and the first injector 31R is fixed so as not to move (rotate) after determining the orientation as described above.

A part of the second injector 41 is arranged in the space sandwiched between the two first connectors 32 of the first injector 31L and the first injector 31R whose positions are determined in this way. Specifically, a part of the second injector 41 is inserted inside a substantially triangular space having two first connectors 32 protruding from the outer periphery of the first injector 31L and the first injector 31R as two sides. It has become.

According to this configuration, the second injector 41 is close to the first injectors 31L and 31R without being hindered by the respective first connectors 32 protruding from the first injectors 31L and 31R provided for each cylinder. It can be arranged close to the combustion chamber 20 at a position, that is, in a direction along the intake passage. As a result, in the fuel supply device in which the second injector 41 is arranged at a position relatively farther from the combustion chamber 20 than the first injectors 31L and 31R, the second fuel injected by the second injector 41 enters the combustion chamber 20. It is possible to reduce the timing lag (delay) until the inflow and improve the responsiveness of the fuel supply. That is, the timing difference between the injection by the injectors 31 and 41 and the inflow into the combustion chamber 20 between the first fuel and the second fuel is suppressed to a small extent, and the accuracy of engine compatibility in a bi-fuel vehicle (engine drivability). Is improved.

Further, since the two first injectors 31L and 31R and one second injector 41 provided per cylinder are arranged in a space-efficient manner along the intake passage, the engine 10 having two fuel supply systems can be used. It can be configured compactly.

Further, two first connectors 32 protruding from the two first injectors 31L and 31R extend toward both sides of the second injector 41 for the same cylinder. Therefore, as shown in FIG. 3, when the first harness 34 is connected to the individual first injectors 31L and 31R, the first harness side connector 33 to the first connector 32 is provided in the space on the side of the second injector 41. Can be easily attached and detached.

More specifically, the connection terminal portion 32a of the first connector 32 of the first injector 31L is located on the left side of the second injector 41 and faces diagonally rearward to the left. The connection terminal portion 32a of the first connector 32 of the first injector 31R is located on the right side of the second injector 41 and faces diagonally rearward to the right. Therefore, on the trajectory of inserting the first harness side connector 33 into the first connector 32 (connection terminal portion 32a) on the first injector 31L side, and on the trajectory of inserting the first harness side connector 33, and on the first connector 32 (connection terminal portion 32a) on the first injector 31R side. The second injector 41 is not located on any of the loci on which the first harness-side connector 33 is inserted. As a result, each of the first harness-side connectors 33 can be inserted into the first connector 32 without contacting the second injector 41.

As described above, although the two first injectors 31 and the second injectors 41 are arranged close to each other in the front-rear direction, the first injectors 31 to the first connector 32 of each first injector 31 are arranged without being hindered by the second injectors 41. The 1 harness 34 (first harness side connector 33) can be connected with excellent workability.

As shown in FIG. 4, the second delivery pipe 40 is attached to the engine 10 via two attachment portions 45A and 45B. The two mounting portions 45A and 45B are arranged at different positions in the arrangement direction (left-right direction) of the three second injectors 41A, 41B and 41C. In the present embodiment, the second delivery pipe 40 is attached to the upper part of the intake manifold 22, but the object to which the second delivery pipe 40 is attached is not limited to this. The mounting portions 45A and 45B are fixed by fastening brackets protruding from the second delivery pipe 40 with mounting bolts. The left side mounting portion 45A is located on the left side of the plane PA in the left-right direction, and the right side mounting portion 45B is located between the plane PB and the plane PC in the left-right direction (see FIG. 5). Both the mounting portion 45A and the mounting portion 45B are located slightly behind the second connector 42 in the front-rear direction.

In all three second injectors 41 (41A, 41B, 41C), the second connector 42 faces in the direction away from the adjacent mounting portion 45A or mounting portion 45B in the left-right direction (longitudinal direction of the second delivery pipe 40). Is positioned.

That is, the left side mounting portion 45A is adjacent to the second injector 41A in the left-right direction. The second connector 42 of the second injector 41A projects toward the side opposite to the mounting portion 45A (on the right side of the flat surface PA) with the flat surface PA in between. Further, the right mounting portion 45B is adjacent to the second injector 41B in the left-right direction. The second connector 42 of the second injector 41B projects toward the opposite side (left side of the flat surface PB) with respect to the mounting portion 45B. Adjacent to the second injector 41C in the left-right direction is the mounting portion 45B on the right side. The second connector 42 of the second injector 41C projects toward the opposite side (right side of the flat PC) with respect to the mounting portion 45B.

Then, in the second connector 42 of the second injector 41A, the connection terminal portion 42a faces diagonally rearward to the right, and in the second connector 42 of the second injector 41B, the connection terminal portion 42a faces diagonally rearward to the left, and the second injector 41C In the second connector 42 of the above, the connection terminal portion 42a faces diagonally rearward to the right. Each of the second injectors 41A, 41B, and 41C is fixed so as not to move (rotate) after determining the orientation as described above.

When each of the second injectors 41 is positioned in the orientation of the second connector 42 as described above, as shown in FIG. 3, in the connection of the second harness 44 to the individual second injectors 41, the mounting portion 45A and the mounting portion The second harness-side connector 43 can be easily attached to and detached from the second connector 42 without being hindered by the 45B.

More specifically, the connection terminal portion 42a of the second connector 42 of the second injector 41A is located on the right side of the mounting portion 45A and faces diagonally rearward to the right. The connection terminal portion 42a of the second connector 42 of the second injector 41B is located on the left side of the mounting portion 45B and faces diagonally rearward to the left. The connection terminal portion 42a of the second connector 42 of the second injector 41C is located on the right side of the mounting portion 45B and faces diagonally rearward to the right. Therefore, the mounting portions 45A and 45B are not located on the locus for inserting the second harness side connector 43 into the second connector 42 (connecting terminal portion 42a) of the second injectors 41A, 41B, 41C, respectively. As a result, the respective second harness side connectors 43 can be inserted into the second connector 42 without contacting or being hindered by the mounting portions 45A and 45B, and the assembling workability is good.

Further, since the mounting portions 45A and 45B are located at positions not hindered by the second connector 42 and the second harness 44, the ease of mounting the second delivery pipe 40 is improved.

As described above, according to the fuel supply device of the engine of the present embodiment, two first injectors 31 (31L, 31R) and one second injector 41 are provided for each cylinder, and two first injectors are provided. The two first connectors 32 protruding from the 31 are directed toward each other, and at least a part of the second injector 41 is arranged in the space sandwiched between the two first connectors 32. As a result, the first injector 31 and the second injector 41 can be installed in a space-efficient manner, and the increase in the distance from the combustion chamber 20 can be suppressed to improve the responsiveness of the fuel supply. Further, the layout is excellent in the workability of assembling the first harness side connector 33 to each of the first connectors 32.

Further, in a configuration in which the second delivery pipe 40 is attached to the engine 10 by the attachment portions 45A and 45B, the second connector 42 of the second injector 41 (41A, 41B, 41C) is attached to the attachment portions 45A or the attachments that are adjacent to each other. It is positioned so as to face the direction away from the portion 45B. As a result, the workability of assembling the second harness side connector 43 to each of the second connectors 42 and the workability of assembling the second delivery pipe 40 in the mounting portions 45A and 45B are improved.

The present invention is not limited to the above embodiment, and can be modified in various ways. In the above embodiment, the configuration, control, and the like shown in the accompanying drawings are not limited to this, and can be appropriately changed within the range in which the effects of the present invention are exhibited. In addition, it can be appropriately modified and implemented as long as it does not deviate from the scope of the object of the present invention.

For example, the above embodiment is an example applied to the in-line 3-cylinder engine 10, but the present invention can also be applied to an engine having a different number of cylinders and a cylinder layout from the above embodiment.

Although the engine 10 of the above embodiment uses gasoline as the first fuel and CNG as the second fuel, it may be applied to an engine using other types of fuel.

In the above embodiment, two first injectors 31 are arranged on the side closer to the combustion chamber 20 of the engine 10, and one second injector 41 is arranged on the side farther from the combustion chamber 20. On the contrary, it is also possible to arrange two first injectors on the side far from the combustion chamber and one second injector on the side closer to the combustion chamber. That is, it is possible to configure the layout of the two fuel injection devices of the above embodiment upside down.

As described above, the present invention has the effect of improving the responsiveness of the fuel supply from the fuel injection device that injects two different fuels, and improving the assembling property of the harness to the injector in each fuel injection device. However, it is particularly useful for bi-fuel vehicles where the installation space of the fuel supply system is limited.

10: Engine 11: Cylinder block 12: Cylinder head 13: Cylinder head cover 15: Cylinder 16: Piston 20: Combustion chamber 21: Intake port (intake passage)
22: Intake manifold 23: Intake pipe (intake passage)
30: 1st delivery pipe (1st delivery pipe, 1st fuel injection device)
31: 1st injector (1st injector, 1st fuel injection device)
32: First connector (first connector)
33: First harness side connector (first harness side connector)
34: 1st harness 40: 2nd delivery pipe (2nd delivery pipe, 2nd fuel injection device)
41: Second injector (second injector, second fuel injection device)
42: Second connector (second connector)
43: Second harness side connector (second harness side connector)
44: Second harness 45A: Mounting part 45B: Mounting part

Claims (3)

With multiple intake passages
A first fuel injection device having a first delivery pipe and a plurality of first injectors connected to the first delivery pipe and injecting the first fuel into the intake passage.
A second fuel injection device having a second delivery pipe and a plurality of second injectors connected to the second delivery pipe and injecting a second fuel into the intake passage.
A first connector that protrudes outward from the outer circumference of the first injector and to which the first harness-side connector is connected.
In an engine fuel supply device including a second connector that projects outward from the outer circumference of the second injector and to which a second harness-side connector is connected.
Two of the first injectors are arranged in one of the intake passages, and one of the second injectors is arranged in one of the intake passages.
The two first injectors corresponding to one intake passage are positioned so that the two first connectors face away from each other.
The second injector is an engine fuel supply device, characterized in that at least a part thereof is arranged in a space sandwiched between the two first connectors. The second delivery pipe is attached to the engine by at least two attachments arranged in an array direction of the plurality of second injectors.
The fuel supply device for an engine according to claim 1, wherein the second injector is positioned so that the second connector faces away from the adjacent mounting portions. Claim 1 is characterized in that the two first injectors are arranged on the side closer to the combustion chamber and the second injector is arranged on the side farther from the combustion chamber in the direction along the intake passage. Or the engine fuel supply device according to 2.

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