JP2006070870A - Arrangement structure for fuel system of outboard motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid enlargement of an outboard motor even if the same is provided with a fuel injection device. <P>SOLUTION: A cylinder block 31 forms a V-shape cylinder bank together with a cylinder head, a throttle body 151 is arranged above a part between the cylinder banks LB, RB, and an intake manifold 73 is arranged at the back of the throttle body 151. A high pressure fuel filter 152 and a vapor separator 153 constructing a high pressure fuel system accessory are arranged closely in front and rear between the cylinder banks LB, RB. The high pressure fuel filter 152 and the vapor separator 152 are arranged in a space enclosed by the cylinder banks LB, RB, the intake manifold 73 and the throttle body 151. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel system arrangement structure in an outboard motor equipped with a fuel injection device.

  While environmental problems are being highlighted, at present, four-cycle engines equipped with electronically controlled fuel injection devices are mainly used in internal combustion engines. However, when the fuel injection device is employed, components such as a high pressure pump, a high pressure filter, an ECU (engine control unit), and various sensors are required, leading to an increase in the number of components, weight, and cost.

  In particular, in an outboard motor, since a fuel tank is provided as a separate body and disposed in the ship, it is necessary to include an engine auxiliary machine such as a vapor separator (sub fuel tank). And since it is necessary to arrange | position these engine auxiliary machines around an engine and to cover with an engine cover, when a fuel-injection apparatus is employ | adopted, there exists a problem that an outboard motor will enlarge. Therefore, in an outboard motor equipped with a small engine (mainly a single-cylinder to two-cylinder small displacement engine), a carburetor is still mainstream as a fuel supply system.

Incidentally, a V-type two-cylinder engine employing a fuel injection device is mounted on an outboard motor disclosed in Patent Document 1 below.
JP 2001-132471 A

  However, the above-mentioned Patent Document 1 does not disclose a specific arrangement of the fuel injection device, and there is a problem that the outboard motor becomes large as described above unless the arrangement is devised.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a fuel system for an outboard motor that can avoid an increase in the size of the outboard motor even if the fuel injection device is provided. It is to provide an arrangement structure.

  In order to achieve the above object, the fuel system arrangement structure of the outboard motor according to claim 1 of the present invention includes a first cylinder bank (RB) having a first cylinder (34R) and a second cylinder (34L) having a second cylinder (34L). A fuel system arrangement structure in an outboard motor comprising a V-type two-cylinder four-cycle engine (2) configured to form a V shape with a two-cylinder bank (LB), and an intake port (57 ), Left and right cylinder heads (51) each having an exhaust port (58) formed on the lower surface, a throttle body (151) disposed above the first and second cylinder banks, and downstream of the throttle body And an intake manifold (73) connected to each intake port of the left and right cylinder heads, and surrounded by the first and second cylinder banks and the intake manifold. And having a high pressure fuel system accessory (152, 153) which arranged in between.

  Preferably, the throttle body is connected to the left and right injectors (164) disposed in the intake manifold corresponding to the first and second cylinder banks, and connected to the left and right injectors. A delivery pipe (162, 172) disposed along the left-right direction at a lower position, a fuel supply port (163, 173) provided in the delivery pipe between the left and right injectors, and the fuel supply And a fuel pipe (159, 171) for guiding the fuel supplied from the high-pressure fuel system auxiliary machine to the delivery pipe, being connected to the opening and disposed below the throttle body. (Claim 2).

  Preferably, the high-pressure fuel system auxiliary machine includes a high-pressure fuel filter (152) and a vapor separator (153), and the high-pressure fuel filter and the vapor separator are arranged in the front-rear direction. It is arranged (Claim 3).

  In the configuration according to any one of claims 1 to 3, preferably, the first and second cylinders are respectively disposed on the right side and the left side of the engine and offset in the vertical direction with respect to each other. The machine (166) is arranged on the surface of the engine on the side where the cylinder (34R) arranged on the upper side is located among the right side surface and the left side surface of the engine (claim 4).

  In addition, the code | symbol in the said parenthesis is an illustration.

  According to the present invention, the high-pressure fuel-system auxiliary machine does not protrude forward, backward, left and right than the cylinder bank or the cylinder head, so that even if the fuel injection device is provided, the outboard motor can be prevented from being enlarged. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a longitudinal sectional view of an outboard motor provided with a fuel system arrangement structure according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the outboard motor.

  In the following, for the outboard motor 1, the left side (the hull side) in FIG. 1 is "front", the right side is "rear", the upper side is "upper", the lower side is "lower", and the front side is "port side" The back side will be described as “starboard side”.

  As shown in FIG. 1, the outboard motor 1 includes an engine 2, an oil pan 4 bonded and fixed to the lower surface of the engine 2, a drive shaft housing 5 fixed to the lower portion of the oil pan 4, a drive A gear housing 6 fixed to the lower portion of the shaft housing 5. The engine 2 is an OHV type water-cooled four-cycle V-type two-cylinder engine in which a crankshaft 35 is disposed substantially vertically (in a vertical position). The outboard motor 1 includes an engine cover 8 that can be divided into upper and lower parts, and the engine cover 8 covers the periphery of the engine 2 and the oil pan 4.

  A drive shaft 12 is disposed substantially vertically in the oil pan 4 and the drive shaft housing 5. The drive shaft 12 extends downward in the drive shaft housing 5 and is configured to drive a propeller 15 as a propulsion device via a bevel gear 14 and a propeller shaft 13 in the gear housing 6.

  A pair of left and right upper mounts (not shown) are attached to upper mount mounting portions (not shown) formed on the side surfaces of the oil pan 4 on the port side and starboard side, and these upper mounts are attached to the upper mount bracket 23. It has been. A pair of lower mounts (not shown) are provided on both sides of the drive shaft housing 5, and the lower mounts are attached to the lower mount bracket 25. In the outboard motor 1, the front ends of the upper mount bracket 23 and the lower mount bracket 25 are connected to the clamp bracket 7, and the clamp bracket 7 is fixed to a stern plate of a hull (not shown).

  The clamp bracket 7 is provided with a swivel bracket 21 via a tilt shaft 24, and a pilot shaft 22 is rotatably supported in the swivel bracket 21 in the vertical direction. An upper mount bracket 23 and a lower mount bracket 25 are respectively provided integrally with the upper and lower ends of the pilot shaft 22. As a result, the outboard motor 1 can be steered left and right around the pilot shaft 22 with respect to the clamp bracket 7 and can be tilted up around the tilt shaft 24.

  A cylinder block 31 is arranged at the foremost part (the bow side) of the engine 2, and a cylinder head 51 is arranged behind the cylinder block 31. The cylinder block 31 is covered with a cylinder cover 32 at the forefront. Further, as shown in FIG. 2, the cylinder block 31 and the cylinder head 51 (51L, 51R) form a V-shaped cylinder bank (a port side cylinder bank LB and a starboard side cylinder bank RB). The bank is formed.

  A crankcase 3 that houses the lower portion of the crankshaft 35 is disposed on the lower surfaces of the cylinder block 31 and the cylinder heads 51L and 51R (see also FIG. 3). The crankcase 3 is formed with an oil return hole, and an oil pan 4 is connected to the lower part. The crankshaft 35 is accommodated in such a manner that its upper end is supported on the upper portion of the cylinder block 31 and its lower end is rotatably supported by the crankcase 3. The crankshaft 35 is connected to the drive shaft 12.

  Further, as shown in FIGS. 1 and 2, between the cylinder banks LB and RB, that is, in the vicinity of the tip of the V-shaped bank in the cylinder block 31 and behind the crankshaft 35, parallel to the crankshaft 35. A camshaft 41 is arranged. The camshaft 41 is rotatably supported at its upper end on the cylinder block 31 and at its lower end on the crankcase 3. A crank gear 42 is fixed to the lower end side of the crankshaft 35, and a cam gear 43 is fixed to the lower end side of the camshaft 41. An idle gear 44 is rotatably supported on the crankcase 3. The position of the idle gear 44 in the vertical direction is substantially the same as the positions of the cam gear 43 and the crank gear 42. The idle gear 44 is also disposed at a position offset to the starboard side in the left-right direction. The idle gear 44 is located below a cylinder 34R described later, and partially overlaps the cylinder 34R in plan view. The idle gear 44 meshes with the crank gear 42 and the cam gear 43 to transmit the rotational driving force of the crankshaft 35 to the camshaft 41.

  As shown in FIG. 1, a water pump 17 driven by a drive shaft 12 is installed on the upper portion of the gear housing 6, and a water suction port 18 is provided in the gear housing 6. The oil pan 4 is provided with a water reservoir 19, and external water (seawater, lake water, river water, etc.) taken as cooling water from the water intake port 18 by the water pump 17 is supplied to the water through the water tube 20. It is supplied to the reservoir 19. The water stored in the water reservoir 19 cools the cylinder block 31 and the left and right cylinder heads 51 (51L, 51R; see FIGS. 2 and 3) through a cooling water passage (not shown), and then the exhaust gas and the propeller 15 It is discharged from the center hole to the outside of the outboard motor 1.

  An oil pump 45 is installed at the lower end of the camshaft 41 in the crankcase 3, and an oil strainer 16 extending to the bottom of the oil pan 4 is connected to the oil pump 45. Lubricating oil (hereinafter simply referred to as “oil”) stored in the oil pan 4 is sucked up by an oil pump 45 through an oil strainer 16 and fed to various parts in the engine 2 as will be described later. The oil pan 4 is returned again.

  FIG. 3 is a rear view of the engine 2 and the oil pan 4 of the outboard motor 1, and FIG. 4 is a partial cross-sectional view of the outboard motor 1. FIG. 5 is a top view showing a schematic configuration of the outboard motor 1, and FIG. 6 is a starboard side view of the engine 2 and the oil pan 4.

  As described above, as shown in FIGS. 2 and 3, the engine 2 includes a pair of left and right cylinder heads 51 (51L, 51R) that form a V-shaped cylinder bank that opens rearward in plan view. Is provided. Further, as shown in FIG. 3, the cylinder head 51R is parallel to the crankshaft 35 and offset upward with respect to the cylinder head 51L. That is, the cylinder head 51R is provided at a position higher than the cylinder head 51L by a predetermined offset amount in the axial direction of the crankshaft 35. In contrast, the cylinder head 51R may be offset downward with respect to the cylinder head 51L.

  As shown in FIG. 2, the port side cylinder bank LB and the starboard side cylinder bank RB are basically configured in the same manner. Inside the cylinder block 31, one cylinder (one cylinder bank LB, RB) is arranged on each side of the cylinder 34 ( 34L, 34R) are formed. On the other hand, on the cylinder head 51 side, as shown in FIG. 4, a combustion chamber 33 aligned with each cylinder 34 and an intake port 57 and an exhaust port 58 communicating with the combustion chamber 33 are formed vertically. The intake port 57 and the exhaust port 58 are opened on the upper surface and the lower surface of the cylinder head 51, respectively. Between the intake port 57 and the exhaust port 58, a spark plug 60 for igniting the compressed air-fuel mixture in the combustion chamber 33 is attached to each combustion chamber 33 (see FIG. 2). Head covers 52 and 59 are mounted on the cylinder heads 51L and 51R, respectively.

  As shown in FIG. 4, an intake valve 53 is attached to each of the cylinder heads 51L and 51R so that the intake port 57 can be opened and closed, and an exhaust valve 54 is attached so that the exhaust port 58 can be opened and closed. As shown in FIG. 2, a rocker arm 55 is pivotally supported in the head cover 59 so as to correspond to each of the intake valve 53 and the exhaust valve 54. Each rocker arm 55 engages with a corresponding push rod 56 at the inner end of the cylinder bank, and abuts the intake valve 53 and the exhaust valve 54 at the outer end of the cylinder bank (see FIG. 4).

  As shown in FIG. 1, the camshaft 41 sequentially moves the intake valve 53 of the cylinder head 51R in the axial direction and the intake valve 53 of the cylinder head 51L in the axial direction. An LI cam 41b for moving the exhaust valve 54 of the cylinder head 51R in its axial direction, an LE cam 41d for moving the cylinder head 51L exhaust valve 54 in its axial direction, and And a fuel pump drive cam 41i for driving the low-pressure fuel pump 166. The fuel pump drive cam 41 i is positioned on the cam gear 43.

  Each of the cams 41a, 41b, 41c, and 41d is in contact with a corresponding push rod 56, and when the cam shaft 41 rotates, each push rod 56 is moved in its longitudinal direction along the corresponding cam profile, As a result, the corresponding rocker arm 55 swings. Then, the intake valve 53 of the cylinder head 51R, the intake valve 53 of the cylinder head 51L, the exhaust valve 54 of the cylinder head 51R, and the exhaust valve 54 of the cylinder head 51L are moved, respectively, and the combustion chambers 33 of the intake port 57 and the exhaust port 58 are moved. The communication to is opened and closed by an intake valve 53 and an exhaust valve 54, respectively.

  As shown in FIG. 2, in each cylinder 34 (34L, 34R) of the cylinder block 31, one piston 37 is slidably inserted in the corresponding cylinder 34. A piston pin 38 is rotatably supported by a corresponding connecting rod 36 that is rotatably attached to the shaft 35.

  As shown in FIG. 1, a flywheel magnet 61 is fixed to the upper end side of the crankshaft 35, and a battery charge coil 62 included in the flywheel magnet 61 is cranked above the cylinder block 31. It is fixed around the shaft 35. As shown in FIGS. 1 and 5, a flywheel magnet cover 63 containing a flywheel magnet 61 is attached to the upper portion of the cylinder block 31. An intake silencer 68 is disposed above the flywheel magnet cover 63. A throttle body 151 communicating with the intake silencer 68 is disposed behind the intake silencer 68 and above the cylinder banks LB and RB of the cylinder block 31.

  As shown in FIGS. 5 and 6, a starter motor 77 is disposed in front of the port side of the cylinder block 31. A low pressure fuel filter 167 is disposed in front of the starboard side of the cylinder block 31. An oil filter 143 is attached to a surface of the cylinder block 31 that faces obliquely forward on the starboard side.

  As shown in FIGS. 2, 5, and 6, on the starboard side of the cylinder block 31, and obliquely behind and below the oil filter 143, one of the low-pressure fuel system auxiliary machines is a mechanical pump. A low pressure fuel pump 166 is provided. In other words, the low-pressure fuel pump 166 is disposed using a space below the cylinder 34 </ b> R that is offset upward among the cylinders 34 of the cylinder block 31. Further, in the cylinder block 31, a plunger 168 is reciprocally disposed below the cylinder 34R, and the low pressure fuel pump 166 is driven by the fuel pump driving cam 41i of the camshaft 41 via the plunger 168 ( (See FIG. 2). As a result, the low pressure fuel pump 166 can be driven by the camshaft 41 using the space below the cylinder 34R disposed on the upper side, so that a drive gear for the low pressure fuel pump 166 is provided on the camshaft 41. There is no need to provide it separately, which contributes to space saving. Also, the maintainability of the low pressure fuel pump 166 is good. The low pressure fuel pump 166 and the low pressure fuel filter 167 are connected by a fuel pipe (not shown).

  As shown in FIG. 5, an ECM (engine control module) 158 is disposed on the surface of the cylinder block 31 opposite to the surface on which the oil filter 143 is provided, that is, on the port side of the cylinder block 31. . As shown in FIGS. 3 and 6, the fuel cooler 161 for cooling the fuel is horizontally fixed to the rear portion of the crankcase 3. Cooling water is supplied to the fuel cooler 161. A first fuel return pipe 160 into which fuel is introduced and a second fuel return pipe 165 through which cooled fuel is led out are connected to the right end and the left end of the fuel cooler 161, respectively.

  As shown in FIGS. 3 and 5, an intake manifold 73 is arranged behind the throttle body 151. The intake manifold 73 includes a communication pipe 74, a port side intake pipe 76 </ b> L branched from one end of the communication pipe 74, and a starboard side intake pipe 76 </ b> R, and the other end of the communication pipe 74 is connected to the downstream side of the throttle body 151. Thus, intake manifold 73 and throttle body 151 are communicated. The intake pipe 76L is connected to the cylinder head 51L, and the intake manifold 73 and the intake port 57 of the cylinder head 51L communicate with each other. The intake pipe 76R is connected to the cylinder head 51R, and the intake manifold 73 and the intake air of the cylinder head 51R. The port 57 is communicated (see FIG. 4).

  Injector pipes 164 (164L, 164R) are disposed in the vicinity of cylinder heads 51L, 51R of intake pipes 76L, 76R, respectively. Delivery pipes 162 (162L, 162R) extending horizontally along the left-right direction are connected to the injectors 164L, 164R. These injectors 164L, 164R or delivery pipes 162L, 162R are offset by an amount corresponding to the offset amount in the vertical direction of the cylinders 34L, 34R, and both are disposed at positions below the throttle body 151. . The delivery pipes 162L and 162R have the same shape and the same length, and can share both.

  Further, between the injectors 164L and 164R, unions 163L and 163R for supplying fuel from a high-pressure fuel filter 152 described later are provided at the inner ends of the delivery pipes 162L and 162R, and the unions 163L and 163R are provided with the unions. The fuel pipes 159L and 159R are connected. The injectors 164L and 164R inject high-pressure fuel into the intake pipes 76L and 76R, and the injected fuel is mixed with the outside air introduced into the corresponding intake port 57 to form a mixture with a desired air-fuel ratio. Is done. This air-fuel mixture is used for combustion in each of the cylinders 34L and 34R.

  As shown in FIGS. 2 and 3, the high-pressure fuel filter 152 and the vapor separator 153 that constitute the high-pressure fuel system auxiliary machine are disposed between the cylinder banks LB and RB. The high-pressure fuel filter 152 is disposed on the front side, and the vapor separator 153 is disposed on the rear side, close to each other. The high pressure fuel filter 152 and the vapor separator 153 are located below the throttle body 151 and the intake manifold 73 and are disposed at substantially the same height as the cylinder block 31. Therefore, the high-pressure fuel filter 152 and the vapor separator 153 are arranged in a space surrounded by the cylinder banks LB and RB, the intake manifold 73 and the throttle body 151. As a result, the dead space in the upper rear part of the engine 2 is effectively used to arrange them, which not only contributes to space saving but also in the front / rear and left / right directions than the cylinder banks LB and RB through the cylinder head 51. Since it does not protrude, enlargement of the outboard motor 1 is avoided.

  The vapor separator 153 includes a vapor separator tank (not shown), a pressure regulator, and a high pressure fuel pump. As shown in FIG. 3, the fuel separators 154 and 169 and the fuel outlet 155 are provided in the vapor separator 153. The high pressure fuel filter 152 is provided with a fuel inlet 156 and a fuel outlet 157. The low-pressure fuel pump 166 is connected to the fuel inlet 154 of the vapor separator 153 by a fuel pipe (not shown). The fuel outlet 155 of the vapor separator 153 and the fuel inlet 156 of the high-pressure fuel filter 152 are connected by a fuel pipe (not shown). The second fuel return pipe 165 is connected to the fuel inlet 169 of the vapor separator 153 and returns the cooled fuel to the pressure regulator built in the vapor separator 153.

  Further, a branch pipe (not shown) is provided in a space surrounded by the cylinder banks LB and RB and the intake manifold 73 and indicated by P1 in FIG. The branch pipe is configured in a cross shape, for example, and has one inlet for introducing fuel and three outlets for discharging the fuel. Note that one inlet and three outlets may be obtained by connecting two T-shaped branch pipes.

  A fuel outlet 155 of the vapor separator 153 is connected to a fuel inlet 156 of the high pressure fuel filter 152 by a fuel pipe (not shown). The fuel outlet 157 of the high-pressure fuel filter 152 is connected to the inlet of the branch pipe disposed at the position P1 by a fuel pipe (not shown). One of the three outlets of the branch pipe is connected to the first fuel return pipe 160 of the fuel cooler 161, and the other two are connected to the unions 163L and 163R through the fuel pipes 159L and 159R, respectively. Then, the fuel is supplied to the delivery pipes 162L and 162R. Therefore, the fuel pipe group including the fuel pipes 159L, 159R, the first fuel return pipe 160, etc., for guiding the fuel from the high pressure fuel filter 152 to the delivery pipes 162L, 162R is mostly composed of the throttle body 151. Furthermore, since it is located inside the cylinder banks LB, RB, the intake manifold 73 and the throttle body 151, most of the fuel pipe group is not only protected but also contributes to space saving. .

  The fuel flow is as follows. First, fuel is supplied to a low-pressure fuel pump 166 from a fuel tank (not shown) disposed in the ship via a low-pressure fuel filter 167 and guided to the vapor separator tank built in the vapor separator 153. The vapor separator 153 separates fuel vapor contained in the liquid fuel and guides only this vapor to the intake manifold 73 for recombustion. The fuel from which the fuel vapor is separated is pumped to the high-pressure fuel filter 152 by a high-pressure fuel pump built in the vapor separator 153 at a predetermined pressure.

  After a part of the fuel pumped to the high pressure fuel filter 152 (surplus fuel) is introduced into the fuel cooler 161 from the first fuel return pipe 160 via the branch pipe disposed at the position P1, and cooled, The pressure is returned from the second fuel return pipe 165 to the pressure regulator built in the vapor separator 153. The pressure regulator depressurizes the high-pressure return fuel and sends it to the vapor separator tank.

  On the other hand, another part of the fuel is supplied from the branch pipe arranged at the position P1 to the delivery pipes 162L and 162R, and is injected into the intake pipes 76L and 76R by the injectors 164L and 164R. It is introduced into each cylinder 34L, 34R via 57 and burns.

  According to the present embodiment, the high-pressure fuel filter 152 and the vapor separator 153 that are high-pressure fuel system auxiliary machines are arranged in a space surrounded by the cylinder banks LB, RB, the intake manifold 73, and the throttle body 151. In addition to contributing to space saving by making effective use of dead space, these do not protrude forward, backward, left and right beyond the cylinder banks LB and RB. Therefore, even if a fuel injection device (injector 164) is provided, The enlargement of the outer unit 1 is avoided. It also contributes to the protection of these high-pressure fuel system accessories.

  In addition, since the high-pressure fuel filter 152 and the vapor separator 153 are arranged close to each other, the dead space is effectively used, and these connecting pipes can be shortened, contributing to space saving.

  Further, most of the fuel pipe group for guiding the fuel from the high-pressure fuel filter 152 to the delivery pipes 162L, 162R is located inside the cylinder banks LB, RB, the intake manifold 73 and the throttle body 151, so that the fuel Not only is the majority of the piping group protected, but the piping is compact and contributes to space saving.

  In addition, since the low-pressure fuel pump 166, which is a low-pressure fuel system auxiliary machine, is disposed in the space below the cylinder 34R disposed on the upper side, not only the maintenance performance of the low-pressure fuel pump 166 is good, but also the plunger 168 Since the low pressure fuel pump 166 is driven by the camshaft 41, it is not necessary to separately provide a drive gear for the low pressure fuel pump 166 on the camshaft 41, which contributes to space saving.

  The high-pressure fuel system auxiliary machine and the low-pressure fuel system auxiliary machine are not limited to the high pressure fuel filter 152, the vapor separator 153, and the low pressure fuel pump 166 exemplified above.

(Second Embodiment)
FIG. 7 is a rear view of the engine portion of the outboard motor having the fuel system arrangement structure according to the second embodiment of the present invention.

  The fuel system arrangement structure of the second embodiment is different from the first embodiment in the configuration of the delivery pipe and its related parts, and the other configurations are the same as those in the first embodiment. is there.

  In the second embodiment, the right delivery pipe 162R is the same as that of the first embodiment. As shown in FIG. 7, the left delivery pipe 172 is longer than the delivery pipe 162L and extends to the vicinity of the left end of the delivery pipe 162R. The left end portion of the delivery pipe 162R and the right end portion of the delivery pipe 172 are connected by the connecting portion 170. One union 173 that replaces the two unions 163L and 163R is provided in the connecting portion 170, and the union 173 is connected to one fuel line 171 that replaces the two fuel lines 159L and 159R. The branch pipe disposed at the position P1 only needs to have two outlets, and one outlet supplies the fuel from the high-pressure fuel filter 152 to the fuel cooler 161 as described in the first embodiment. . The other outlet supplies the fuel from the high-pressure fuel filter 152 to the connecting portion 170 via the fuel pipe 171. Then, fuel is supplied from the connecting portion 170 to the delivery pipe 162R and the delivery pipe 172.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained except for the sharing of two delivery pipes.

  Note that the delivery pipe connected to the injectors 164L and 164R may be constituted by a single pipe. In that case, it is only necessary to bend the pipe by the difference in the position in the height direction between the injectors 164L, 164R.

1 is a longitudinal sectional view of an outboard motor provided with a fuel system arrangement structure according to a first embodiment of the present invention. It is a cross-sectional view of the outboard motor. It is a rear view of the engine and oil pan of an outboard motor. It is a fragmentary sectional view of an outboard motor. It is a top view which shows schematic structure of an outboard motor. It is a starboard side side view of an engine and an oil pan. It is a rear view of the engine part of the outboard motor provided with the fuel system arrangement structure concerning the 2nd embodiment of the present invention.

Explanation of symbols

1 Outboard motor 2 Engine LB Cylinder bank (second cylinder bank)
RB cylinder bank (first cylinder bank)
31 Cylinder block 34L Cylinder (2nd cylinder)
34R cylinder (first cylinder)
51 Cylinder head 57 Intake port 58 Exhaust port 73 Intake manifold (intake manifold)
151 Throttle body 152 High pressure fuel filter (high pressure fuel system auxiliary machine)
153 Vapor separator (high pressure fuel system auxiliary machine)
159, 171 Fuel pipe 162, 172 Delivery pipe 163, 173 Union (fuel supply port)
164 Injector 166 Low-pressure fuel pump (low-pressure fuel system auxiliary machine)
167 Low pressure fuel filter

Claims (4)

Fuel system arrangement structure in an outboard motor having a V-type two-cylinder four-cycle engine in which a first cylinder bank having a first cylinder and a second cylinder bank having a second cylinder are V-shaped. Because
Left and right cylinder heads each formed with an intake port on the upper surface and an exhaust port on the lower surface;
A throttle body disposed above the first and second cylinder banks;
An intake manifold connected to the downstream side of the throttle body and connected to the intake ports of the left and right cylinder heads;
A fuel system arrangement structure in an outboard motor comprising: a high-pressure fuel system auxiliary machine arranged in a space surrounded by the first and second cylinder banks and the intake manifold.   Left and right injectors arranged in the intake manifold corresponding to the first and second cylinder banks, and connected to the left and right injectors, and arranged in a horizontal direction at a position below the throttle body. A delivery pipe, a fuel supply port provided in the delivery pipe between the left and right injectors, and a fuel supply port connected to the fuel supply port and disposed below the throttle body. 2. A fuel system arrangement structure in an outboard motor according to claim 1, further comprising fuel piping for guiding the supplied fuel to the delivery pipe.   3. The outboard motor according to claim 1, wherein the high-pressure fuel system auxiliary machine includes a high-pressure fuel filter and a vapor separator, and the high-pressure fuel filter and the vapor separator are arranged at the front and rear. Fuel system arrangement structure.   The first and second cylinders are respectively arranged on the right side and the left side of the engine and are offset from each other in the vertical direction, and the low pressure fuel system auxiliary machine is arranged on the upper side of the right side surface and the left side surface of the engine. The fuel system arrangement structure in an outboard motor according to any one of claims 1 to 3, wherein the cylinder is arranged on a surface on a side where the cylinder is located.

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