JP4061968B2 - Fuel injection engine and outboard motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel injection engine and an outboard motor.
[0002]
[Prior art]
[0003]
[Prior art]
An outboard motor that is attached to the hull of a ship is equipped with an engine, and this outboard motor uses a power of the engine to rotate a propeller to obtain a propulsive force. Some of these engines include an injector that injects fuel into a plurality of cylinders, and uses a fuel injection engine that supplies high pressure fuel boosted by a high pressure fuel pump to the injector via a fuel supply rail.
[0004]
In such a fuel injection type engine, the fuel is increased in pressure (higher than the in-cylinder pressure at the time of compression) due to requirements such as atomization of spray and improved penetration, but in general, the fuel is mechanical In order to perform injection amount correction control in a situation where the fuel pressure does not rise to a predetermined value such as at the time of start (cranking), a high pressure pump of the type is used, as disclosed in Japanese Patent Application Laid-Open No. 2001-65386. In addition, a fuel pressure sensor for detecting the fuel pressure in the high-pressure pipe is provided.
[0005]
In addition, in an engine with high pressure fuel, for safety reasons, the parts that make up fuel piping such as fuel supply rails, high pressure pumps, and high pressure injectors are made of metal with pressure resistance and rigidity and are rigidly attached to the engine. ing.
[0006]
-On the other hand, the fuel pressure sensor attached to the fuel piping path has a built-in electric circuit for amplifying the sensor output and compensating the temperature, so it has sufficient resistance against engine vibration. It is in a situation that cannot be said.
[0007]
[Problems to be solved by the invention]
In particular, engines such as outboard motors that are frequently used in a high load / high rotation range are used for a long time under a large engine vibration condition, so that resistance to vibration is required.
[0008]
In addition, since the fuel pressure sensor that obtains control information is the last of the assembly of the engine parts, there is a problem that, when the fuel pressure sensor is assembled at the same time as the parts of the fuel supply system, it takes time to connect to the control system.
[0009]
The present invention has been made in view of the above points, and an object thereof is to provide a fuel injection engine and an outboard motor that can prevent excessive vibration transmission to a fuel pressure sensor and can be easily assembled. .
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems and achieve the object, the present invention is configured as follows.
[0011]
The invention according to claim 1 is a fuel injection engine comprising an injector for injecting fuel into a plurality of cylinders, and supplying high pressure fuel boosted by a high pressure fuel pump to the injector through a fuel supply rail.
A fuel passage branch member is connected to the high-pressure fuel pump,
The fuel supply branch is connected to the fuel passage branch member via a high pressure hose and a joint,
A fuel pressure sensor for detecting the pressure of the high-pressure fuel is attached to the joining member,
The joint member is attached to the fuel supply rail via an attachment member mounted with a vibration isolator,
The fuel pressure sensor is a fuel injection type engine connected to the fuel supply rail by a detection hose .
[0012]
According to the first aspect of the present invention, the fuel passage branch member is connected to the high-pressure fuel pump, and the fuel supply rail is connected to the fuel passage branch member via the high-pressure hose and the joint so that the pressure of the high-pressure fuel is reduced. The fuel pressure sensor to be detected is attached to the joining member, and the joining member is attached to the fuel supply rail via a mounting member mounted with a vibration isolator . The fuel pressure sensor is connected to the fuel supply rail by the detection hose, so that the engine is relatively It can be easily mounted on a fuel supply rail with low vibrations, preventing excessive transmission of engine vibration to the fuel pressure sensor.
[0013]
According to a second aspect of the present invention, the attachment member is made of a sheet metal, the sheet metal has a holding part and a foot part, the fuel pressure sensor is attached to the holding part, and the foot part is attached to the vibration-proof material. The fuel injection engine according to claim 1, wherein the fuel pressure sensor is attached to the fuel supply rail in a floating state.
[0014]
According to the second aspect of the present invention, the fuel pressure sensor is attached to the holding portion of the sheet metal, and the foot portion is attached to the fuel supply rail in a state of being floated on the fuel supply rail via the vibration isolating material. This prevents excessive engine vibration from being transmitted to the fuel pressure sensor.
[0015]
According to a third aspect of the present invention, the attachment member is made of a sheet metal, the sheet metal has a holding portion and a foot portion, and the vibration-proof material is interposed between the holding portion and the fuel pressure sensor. The fuel injection engine according to claim 1, wherein the foot is attached to the fuel supply rail in a state where the vibration isolator is interposed between the fuel pressure sensor and the fuel supply rail. .
[0016]
According to the third aspect of the present invention, the vibration isolator is interposed between the sheet metal holding portion and the fuel pressure sensor, and the vibration isolator is interposed between the fuel pressure sensor and the fuel supply rail. By attaching the foot to the fuel supply rail, it is possible to prevent transmission of excessive engine vibration to the fuel pressure sensor with a simple mounting structure.
[0017]
According to a fourth aspect of the present invention, the mounting member is constituted by a fastening member, and the fuel pressure sensor is fastened to the fuel supply rail by the fastening member via the vibration isolator and attached to the fuel supply rail. The fuel injection type engine according to claim 1.
[0018]
According to the fourth aspect of the present invention, the fuel pressure sensor is fastened to the fuel supply rail by the tightening member via the vibration isolator and attached to the fuel supply rail. Transmission of engine vibration can be prevented.
[0019]
According to a fifth aspect of the present invention, there is provided an outboard motor comprising a propulsion unit, wherein the propulsion unit is driven by driving a propeller through a power transmission system to obtain a propulsive force. An outboard motor, which is the fuel injection engine according to claim 4.
[0020]
According to the fifth aspect of the present invention, excessive vibration transmission to the fuel pressure sensor can be prevented even in an engine such as an outboard motor that is frequently used at high load and high speed and receives a large amount of vibration for a long time. .
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a fuel injection engine and an outboard motor according to the present invention will be described below in detail with reference to the accompanying drawings.
[0022]
FIG. 1 is a schematic view of an outboard motor showing an example of a fuel injection engine. FIG. 1 (A) is a plan view of the engine, and FIG. 1 (B) is along the line BB in FIG. 1 (A). FIG. 1C is a side view of the outboard motor, and FIG. 1D is a configuration diagram of the fuel supply system.
[0023]
Reference numeral 1 denotes an outboard motor, which is connected to the engine 2 on which the crankshaft 10 is mounted in a vertical state, the guide exhaust 3 connected to the lower end surface of the engine 2 and supporting the engine 2, and the lower end surface of the guide exhaust 3. Upper case 4, lower case 5, and propeller 6.
[0024]
The engine 2 is an in-cylinder injection type V-type six-cylinder two-cycle engine, and the six cylinders # 1 to # 6 are horizontally placed so as to form a V bank in plan view, and arranged in two rows in the vertical direction. A cylinder head 8 is connected and fixed to the cylinder body 7 formed. A cooling water pump 18 driven by the engine 2 is provided in the upper case 4, and the cooling water is circulated through the engine 2 from the cooling water intake 5 a formed in the lower case 5 as indicated by the arrow in the figure, and the propeller 6 is discharged from the vicinity.
[0025]
Pistons 11 are slidably fitted in the cylinders # 1 to # 6 of the engine 2, and each piston 11 is connected to the crankshaft 10. The cylinder head 8 is provided with a solenoid open / close injector (fuel injection valve) 13 and a spark plug 14 that are opened and closed by magnetic force.
[0026]
Each of the cylinders # 1 to # 6 communicates with the crank chamber 12 through a scavenging port (not shown), and an exhaust port 15 is connected to the cylinders # 1 to # 6. The exhaust port 15 in the left bank in FIG. 1B is joined to the left collective exhaust passage 16, and the exhaust port 15 in the right bank is joined to the right collective exhaust passage 17. An intake passage 19 branched from the intake manifold is connected to the crank chamber 12 of the engine 2, and a reed valve 20 for preventing backflow is disposed in the intake passage 19, and the downstream side of the reed valve 20. Is provided with an oil pump 21 for supplying and lubricating oil into the engine 2, and a throttle valve 22 for adjusting the intake air amount is provided upstream of the reed valve 20.
[0027]
As shown in FIG. 1 (D), the fuel in the fuel tank 23 installed on the hull side is passed through a fuel filter 26 by a manual first low-pressure fuel pump 25 and a second low-pressure on the outboard motor side. It is sent to the fuel pump 27. The second low-pressure fuel pump 27 is a diaphragm pump that is driven by the pulse pressure of the crank chamber 12 of the engine 2 and sends fuel to a vapor separator tank 29 that is a fuel tank having a gas-liquid separation function.
[0028]
A fuel preload pump 30 driven by an electric motor is disposed in the vapor separator tank 29. The fuel is pressurized and sent to the pair of high pressure fuel pumps 32 via the preload pipe 31 and the branch pipes 31a and 31b. The discharge side of each high-pressure fuel pump 32 has fuel supply rails arranged in the vertical direction along cylinders # 1, # 3, # 5 in the right bank and cylinders # 2, # 4, # 6 in the left bank. It is connected to 33a, 33b via a high pressure hose 49, and is connected to a vapor separator tank 29 via a high pressure regulating valve 35, a fuel cooler 36, and a return pipe 37.
[0029]
A preload pressure adjustment valve 39 is provided between the preload pipe 31 and the vapor separator tank 29. The pair of high-pressure fuel pumps 32 is driven by the pump drive unit 40. The pump drive unit 40 is connected to the crankshaft 10 via a belt 41.
[0030]
The oil pump 21 for engine lubrication is a pump driven by the rotation of the crankshaft 10, and oil is supplied into the intake passage 19 from a sub tank 50 installed on the hull side through a main tank 51 arranged on the engine side. Supply. The oil in the main tank 51 is configured to be supplied to the vapor separator tank 29 via the filter 52, the premix oil pump 53, and the check valve 54. The premix oil pump 53 employs a system driven by an electromagnetic solenoid or a pump driven by an electric motor.
[0031]
Detection signals from various sensors indicating the operating state of the engine 2 and the state of the outboard motor 1 are input to the ECU (electronic control unit) 42. For example, an engine rotation speed sensor 43 that detects the rotation angle (rotation speed) of the crankshaft 10, an intake air temperature sensor 44 that detects the temperature in the intake passage 19, a throttle opening sensor 45 that detects the opening of the throttle valve 22, The air-fuel ratio sensor 46 for detecting the air-fuel ratio in the uppermost cylinder # 1, the fuel pressure sensor 47 for detecting the pressure of the high-pressure fuel, the cooling water temperature sensor 48 for detecting the cooling water temperature of the engine 2, and the water separated by the fuel filter 26 A water detection sensor 55 for detecting the amount of exhaust gas, an exhaust pressure sensor 38 for detecting exhaust pressure, an oil level sensor 56 for detecting the amount of oil in the main tank 51, an outside air temperature sensor 57, a trim sensor 28 for detecting the attitude of the engine, etc. Various detection signals are input. The ECU 42 performs arithmetic processing on the detection signals of these sensors based on the control map, and transmits the control signals to the injector driver 42a, the injector 13, the spark plug 14, the preload fuel pump 30, and the premix oil pump 53.
[0032]
The engine 2 preloads the fuel in the vapor separator tank 29 by a fuel preload pump 30, the pressurized fuel is pressurized by a high pressure fuel pump 32, and the pressurized high pressure fuel is a pressure regulating valve. At 35, surplus fuel exceeding the set pressure is returned to the vapor separator tank 29, and only the necessary high-pressure fuel is supplied to the fuel supply rail 33 and supplied to the injectors 13 attached to the cylinders # 1 to # 6. The oil pump 21 is driven by the rotation of the crankshaft 10 and supplies oil from the sub tank 50 and the main tank 51 into the intake passage 19 to lubricate the inside of the engine.
[0033]
FIG. 2 is a plan view of the outboard motor of FIG. In the following description, the same components as those shown in FIG.
[0034]
A flywheel 73 is fixed to the crankshaft 10, and a driving pulley 60 is attached to an upper portion thereof, that is, an upper end of the crankshaft 10, and a driven pulley 62 is provided on the rotating shaft 61 of the pump driving unit 40. A belt 41 is stretched between 60 and the driven pulley 62. A pair of high-pressure fuel pumps 32 are attached to both sides of the pump drive unit 40 by bolts 59. Thereby, the rotation of the crankshaft 10 is transmitted to the rotating shaft 61 via the belt 41 so as to drive each high-pressure fuel pump 32.
[0035]
The fuel supply rails 33a and 33b and the injector 13 are fixed to the cylinder head 8, and the injector 13 is connected to the fuel supply rails 33a and 33b. The high-pressure fuel pump 32 has a built-in high-pressure adjustment valve 35, and each high-pressure fuel pump 32 is connected with a fuel passage branch member 350 for branching a passage for supply and discharge. 350 are connected to each other by a connecting hose 75, and the pair of fuel passage branch members 350 are connected to the left and right fuel supply rails 33a and 33b by joints 69a and 69b and a high-pressure hose 49, respectively. In the figure, 70 is a starter motor, 71 is a belt tensioner, and 72 is a silencer.
[0036]
3 is a view from the Y direction in FIG. 2, FIG. 4 is a side view from the X direction in FIG. 3, FIG. 5 is a side view of the cylinder head, and FIG. 6 is a state in which a fuel supply rail is attached to the cylinder head. FIG. 7 is a side view, and FIG. 7 is a plan view showing attachment of the fuel supply rail.
[0037]
As shown in FIGS. 3 and 4, the pair of fuel passage branch members 350 are connected to each other by a connecting hose 75. The fuel passage branch member 350 is connected to a pair of left and right fuel supply rails 33a and 33b via high pressure hoses 49 by joints 69a and 69b. The injectors 13 connected to the pair of fuel supply rails 33a and 33b are fixed to the mounting portions 8a of the left and right cylinder heads 8 as shown in FIGS.
[0038]
On the opposite side of the pair of cylinder heads 8, mounting bosses 8 b are formed so as to protrude from the head cover 81 as shown in FIGS. 5 to 7. The fuel supply rails 33a and 33b are applied to the mounting boss 8b, the collar 100 is inserted into the mounting boss 8b from the fuel supply rails 33a and 33b, and the tightening bolt 101 is inserted into the collar 100 and fixed to the mounting boss 8b. To do. As described above, the fuel supply rails 33a and 33b for supplying the high-pressure fuel are firmly and directly fixed to the cylinder head 8 so as not to be rattled by engine vibration.
[0039]
Further, as shown in FIG. 8, the mounting portion 8c having the flat surface 8c1 is processed without forming the mounting boss 8b on the cylinder head 8, the spacer 102 is applied to the mounting portion 8c, and the collar 100 is attached to the fuel supply rail 33a. , 33b may be inserted into the mounting portion 8c via the spacer 102, and the fastening bolt 101 may be inserted into the collar 100 to be fastened and fixed to the mounting portion 8c. In this embodiment, the mounting position of the fuel supply rails 33a and 33b can be adjusted by the size of the spacer 102, and the cylinder head 8 can be shared.
[0040]
On the wall surface of the cylinder body 7, an electrical component box 77 is mounted between the V banks B1 and B2. The electrical component boxes 77 incorporate circuit components of the ECU 42 and the injector driver 42a shown in FIG. 1 in each box.
[0041]
In this invention, as shown in FIGS. 9 to 14, the joining member 470 to which the fuel pressure sensor 47 for detecting the pressure of the high-pressure fuel is attached is attached to the attachment member 120 mounted on the fuel supply rail 33b by the vibration isolator 110. Is attached through.
[0042]
In the present invention, the joining member 470 having the fuel pressure sensor 47 attached to the fuel supply rail 33b having relatively small engine vibration can be easily attached, and transmission of excessive engine vibration to the fuel pressure sensor 47 can be prevented. The fuel pressure sensor 47 can be attached at the end of the assembly of the engine parts and connected to the control system without being assembled at the same time as the parts of the fuel supply system, so that the assembly is easy and the productivity is improved.
[0043]
In the embodiment shown in FIGS. 9 and 10, the mounting member 120 is formed of a pressed aluminum sheet metal 121, and the sheet metal 121 has a holding part 121a and a foot part 121b. The joining member 470 with the detection hose 140 to which the fuel pressure sensor 47 is attached is applied to the holding portion 121a of the sheet metal 121, and the joining member 470 is tightened with the screw 130 and attached to the holding portion 121a. The foot portions 121b on both sides of the holding portion 121a of the sheet metal 121 are provided with vibration-proofing materials 110a and 110b formed of an elastic body such as rubber on both sides, and the fastening bolt 131 is fastened and fixed to the fuel supply rail 33b. The fuel pressure sensor 47 attached to the joining member 470 is connected to the fuel supply rail 33b by the detection hose 140 and detects the fuel pressure.
[0044]
In this embodiment, the joining member 470 is attached to the holding part 121a of the sheet metal 121, the engine vibration is absorbed by the vibration isolator 110a and 110b to which the foot part 121b is attached, and the joining member 470 is attached from the fuel supply rail 33b. By mounting the fuel pressure sensor 47 in a floating state, it is possible to prevent excessive engine vibration from being transmitted to the fuel pressure sensor 47 with a simple mounting structure.
[0045]
In the embodiment shown in FIGS. 11 and 12, the mounting member 120 is made of a sheet metal 121, and the sheet metal 121 has a holding part 121a and a foot part 121b as in the embodiment shown in FIGS. . A vibration isolator 110c formed of an elastic body such as rubber is interposed between the holding portion 121a of the sheet metal 121 and the bonding member 470, and an elastic body such as rubber is provided between the bonding member 470 and the fuel supply rail 33b. The foot 121b is fastened and fixed to the fuel supply rail 33b by the fastening bolts 132 with the formed vibration isolator 110d interposed.
[0046]
In this embodiment, the foot 121b is attached to the fuel supply rail 33b with the joint member 470 disposed on both sides of the holding member 121a of the sheet metal 121, so that the fuel supply rail 33b The engine vibration transmitted through the holding portion 121a of the sheet metal 121 is absorbed by the vibration isolator 110c, and the engine vibration transmitted directly from the fuel supply rail 33b is absorbed by the vibration isolator 110d, so that the mounting is simple. Excessive engine vibration can be prevented from being transmitted to the fuel pressure sensor 47 attached to the joining member 470 with a structure. Further, the fuel pressure sensor 47 can be easily attached to the fuel supply rail 33b by attaching the joining member 470 and the vibration isolator 110c, 110d to the holding portion 121a in advance with the screw 130.
[0047]
In the embodiment of FIGS. 13 and 14, the mounting member 120 is constituted by a fastening member 122 constituted by a bolt, and this fastening member 122 is attached to the fuel supply rail 33 b via a collar 123, and the fuel pressure sensor 47. The joint member 470 with the detection hose 140 to which is attached is fastened and fixed to the fuel supply rail 33b. A vibration isolator 110e formed of an elastic body such as rubber is interposed between the head 122a of the tightening member 122 and the fuel supply rail 33b, and rubber is interposed between the fuel supply rail 33b and the joining member 470. The anti-vibration material 110f formed of an elastic body or the like is interposed, and the joining member 470 is fastened and attached to the fuel supply rail 33b in a state where the joining member 470 is floated from the fuel supply rail 33b.
[0048]
In this embodiment, the joining member 470 is fastened to the fuel supply rail 33b by the fastening member 122 via the vibration isolating materials 110e and 110f and attached to the fuel supply rail 33b in a state of being floated, thereby joining with a simple attachment structure. Transmission of excessive engine vibration to the fuel pressure sensor 47 attached to the member 470 can be prevented.
[0049]
The present invention is not limited to a two-cycle engine such as an outboard motor, which is frequently used at a high load and high rotation, and is subjected to a large vibration for a long time, and can also be applied to a four-cycle engine. Applicable.
[0050]
【The invention's effect】
As is clear from the above description, in the invention according to claim 1, the fuel passage branch member is connected to the high pressure fuel pump, and the fuel supply rail is connected to the fuel passage branch member via the high pressure hose and the joint. A fuel pressure sensor for detecting the pressure of the high-pressure fuel is attached to the joining member, and the joining member is attached to the fuel supply rail via a mounting member mounted with a vibration isolator , and the fuel pressure sensor is connected to the fuel supply rail by a detection hose. Thus, it can be easily attached to a fuel supply rail with relatively small engine vibration, and transmission of excessive engine vibration to the fuel pressure sensor can be prevented.
[0051]
According to the second aspect of the invention, the fuel pressure sensor is attached to the holding portion of the sheet metal, and the foot portion is attached to the fuel supply rail in a state of being floated on the fuel supply rail via the vibration isolator, so that the fuel pressure sensor has a simple mounting structure. Transmission of excessive engine vibration to the can be prevented.
[0052]
In the invention according to claim 3, while the vibration isolator is interposed between the sheet metal holding portion and the fuel pressure sensor, and the vibration isolator is interposed between the fuel pressure sensor and the fuel supply rail, By attaching to the fuel supply rail, transmission of excessive engine vibration to the fuel pressure sensor can be prevented with a simple mounting structure.
[0053]
In the invention described in claim 4, the fuel pressure sensor is fastened to the fuel supply rail by the fastening member via the vibration isolator and attached to the fuel supply rail, so that excessive engine vibration to the fuel pressure sensor can be prevented with a simple mounting structure. Transmission can be prevented.
[0054]
According to the fifth aspect of the present invention, excessive vibration transmission to the fuel pressure sensor can be prevented even in an engine such as an outboard motor that is frequently used at high load and high rotation and receives large vibrations for a long time.
[Brief description of the drawings]
FIG. 1 is a schematic view of an outboard motor showing an example of a fuel injection type engine.
FIG. 2 is a plan view of the outboard motor of FIG.
FIG. 3 is a view as seen from the Y direction in FIG. 2;
4 is a side view seen from the X direction in FIG. 3. FIG.
FIG. 5 is a side view of a cylinder head.
FIG. 6 is a side view of a state in which a fuel supply rail is attached to a cylinder head.
FIG. 7 is a plan view showing attachment of a fuel supply rail.
FIG. 8 is a plan view of another embodiment showing attachment of a fuel supply rail.
FIG. 9 is a side view showing an attached state of the fuel pressure sensor.
10 is a view as seen from the direction of the arrow in FIG. 9;
FIG. 11 is a side view of another embodiment showing an attached state of the fuel pressure sensor.
12 is a view seen from the direction of the arrow in FIG.
FIG. 13 is a side view of another embodiment showing an attached state of the fuel pressure sensor.
14 is a view seen from the direction of the arrow in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Outboard motor 2 Engine 13 Injector 32 High pressure fuel pump 33a, 33b Fuel supply rail 47 Fuel pressure sensor 110 Vibration isolator 120 Attachment member

Claims (5)

In a fuel injection engine that includes an injector that injects fuel into a plurality of cylinders, and that supplies high pressure fuel boosted by a high pressure fuel pump to the injector through a fuel supply rail.
A fuel passage branch member is connected to the high-pressure fuel pump,
The fuel supply branch is connected to the fuel passage branch member via a high pressure hose and a joint,
A fuel pressure sensor for detecting the pressure of the high-pressure fuel is attached to the joining member,
The joint member is attached to the fuel supply rail via an attachment member mounted with a vibration isolator,
The fuel injection type engine is characterized in that the fuel pressure sensor is connected to the fuel supply rail by a detection hose . The mounting member is made of a sheet metal, and the sheet metal has a holding part and a foot part,
Attach the fuel pressure sensor to the holding part,
2. The fuel injection engine according to claim 1, wherein the foot portion is attached to the fuel supply rail in a state where the fuel pressure sensor is floated through the vibration isolator. 3. The mounting member is made of a sheet metal, and the sheet metal has a holding part and a foot part,
While the vibration isolator is interposed between the holding portion and the fuel pressure sensor, and the vibration isolator is interposed between the fuel pressure sensor and the fuel supply rail, the foot is connected to the fuel supply rail. The fuel injection type engine according to claim 1, wherein the fuel injection type engine is attached to the engine.   The said attachment member is comprised with a clamping member, The said fuel pressure sensor is clamped to the said fuel supply rail by the said clamping member via the said vibration isolator, and it attaches to the said fuel supply rail. Fuel injection engine.   An outboard motor comprising a propulsion unit and obtaining propulsion power by driving a propeller through a power transmission system with the power of the engine of the propulsion unit. The engine according to any one of claims 1 to 4. An outboard motor, which is the fuel injection type engine described.

Images