JP6186299B2 - Air intake structure for saddle-ride type vehicles - Google Patents

Description

  The present invention relates to an intake structure for a saddle-ride type vehicle equipped with a fuel injection valve.

  A conventional saddle-ride type vehicle intake structure includes a main frame that extends rearward from the head pipe and then downwards on the central axis of the vehicle, and is arranged behind the main frame to take in outside air. In order to connect the air cleaner to be filtered and the intake port formed in the cylinder head, the passage between the intake port and the air cleaner is curved to avoid the main frame to prevent crossing the main frame It was necessary to be.

  However, in general, in an internal combustion engine, the closer the shape of the intake passage between the intake port and the throttle valve that controls the intake amount is closer to a straight line, the lower the intake resistance in the intake passage and the better the performance of the internal combustion engine. Fuel consumption is improved. Therefore, in order to reduce the intake resistance between the throttle valve and the intake port and improve the performance and fuel consumption of the internal combustion engine, the main frame, at the part intersecting the carburetor provided with the throttle valve, An intake structure for a saddle-ride type vehicle has been disclosed in which a recess for avoiding a carburetor is provided to reduce overhang of the intake passage toward the side of the main frame to reduce the curvature of the intake passage (see Patent Document 1). ).

  In such an intake structure for a saddle-ride type vehicle, a recess for avoiding a carburetor is formed in the main frame. Therefore, it is necessary to change the cross-sectional shape of the recess to the shape of the other part of the main frame. Will increase. Further, in the intake structure in which the supply of fuel mixed with air is changed from the carburetor to the fuel injection valve in order to improve the fuel efficiency of the internal combustion engine, when the intake passage is curved, the fuel is injected from the fuel injection valve. Sprayed fuel tends to adhere to the inner wall surface of the intake passage, and the sprayed fuel wall surface hinders atomization of the injected fuel, preventing improvement in the output and fuel consumption of the internal combustion engine. There was a need for a built-in intake structure.

JP 2007-062601 A

  The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the intake resistance of the intake passage and reduce the intake resistance of the intake passage without changing the cross-sectional shape of the main frame. Even when equipped with an injection valve, the intake structure of a saddle-ride type vehicle that prevents the sprayed fuel injected from the fuel injection valve from adhering to the inner wall surface of the intake passage and improves the performance of the internal combustion engine to improve the output and fuel consumption Is to provide.

  In order to achieve the above object, the invention according to claim 1 is directed to a saddle-ride type vehicle having a frame member arranged on a vehicle body center line so as to surround a cylinder head of the internal combustion engine from the upper side to the rear side of the internal combustion engine. In the intake structure, the intake structure is provided with a fuel injection valve, connected to an intake port of a cylinder head of the internal combustion engine, and connected to an upstream side of the inlet pipe, and an intake amount is limited by a throttle valve. And a connecting tube connected to the upstream side of the throttle body, and the intake port of the cylinder head has an inlet port of the intake port directed toward an outlet of the connecting tube when viewed in the cylinder axial direction. The fuel injection valve of the inlet pipe is inclined and The sprayed fuel to be sprayed is formed in a gently curved shape so as to go from the intake port inlet to the intake port outlet, and the throttle body and the inlet pipe are located in front of the vehicle body from the frame member behind the internal combustion engine. The connecting tube is curved and connected to the throttle body so as to bypass the frame member behind the internal combustion engine.

  The invention according to claim 2 is the intake structure of the saddle-ride type vehicle according to claim 1, wherein the inlet pipe includes a cylinder head side flange portion on the cylinder head side and a throttle body side flange portion on the throttle body side. A pair of bolt mounting portions are formed on the cylinder head side flange portion and the throttle body side flange portion so as to project at right angles to the central axis of the inlet pipe, and the inlet pipe includes the bolt Fastened to the cylinder head by a cylinder head fastening member inserted through the mounting portion, fastened to the throttle body by a throttle body fastening member inserted through the bolt mounting portion, and the cylinder head fastening member and the throttle body fastening member; At the axial center of the inlet pipe It is characterized in that is inserted into and displaced positions.

According to a third aspect of the present invention, in the intake structure of the saddle-ride type vehicle according to the second aspect, the fuel injection valve provided in the inlet pipe is located above the bolt mounting portion of the cylinder head side flange portion. And it is arrange | positioned adjacent to the said throttle body fastening member inserted in one said bolt attachment part of the said throttle body side flange part.

  According to a fourth aspect of the present invention, in the intake structure of the saddle-ride type vehicle according to the third aspect, the fuel injection valve mounting portion provided on the inlet pipe and to which the fuel injection valve is fastened is provided on the throttle body side flange portion. One throttle body fastening member inserted through the bolt mounting portion and the fuel injection valve are provided on opposite sides of the fuel injection valve.

The invention according to claim 5, an intake structure for a saddle type vehicle according to claim 4, in the throttle body, the valve shaft is provided for rotating the throttle valve at a right angle to the axial direction of the throttle body A throttle drum and an opening sensor are provided at both ends of the valve shaft, and a fuel hose connected to the fuel injection valve is connected to the fuel injection valve from the opposite side of the throttle drum. To do.

  According to the first aspect of the present invention, the intake port of the cylinder head is inclined so that the inlet of the intake port faces the outlet of the connecting tube when viewed in the cylinder axial direction, and the sprayed fuel from the fuel injection valve is Since it is formed in a gently curved shape so as to go from the intake port inlet to the intake port outlet, the intake resistance in the intake port can be reduced and the fuel sprayed from the fuel injection valve Adhering to the inner wall of the is reduced. Further, the throttle body and the inlet pipe are disposed on the front side of the vehicle body with respect to the frame member behind the internal combustion engine, and the connecting tube is curved so as to bypass the frame member behind the internal combustion engine and connected to the throttle body. The throttle valve can be brought close to the vehicle center line without affecting the degree of freedom of shape, the bending of the intake passage from the intake port to the throttle valve can be reduced, and the intake resistance can be further reduced. The engine performance can be improved and the output and fuel consumption can be improved.

According to the intake structure for an internal combustion engine according to claim 2, the inlet pipe is provided with a cylinder head side flange portion and a throttle body side flange portion, and each of the cylinder head side flange portion and the throttle body side flange portion includes A pair of bolt mounting portions are formed to project at right angles to the central axis of the inlet pipe, are fastened to the cylinder head by a cylinder head fastening member that is inserted into the cylinder head side flange portion, and are inserted into the throttle body side flange portion. Since the throttle body is fastened to the throttle body by the throttle body fastening member, the cylinder head fastening member and the throttle body fastening member are fastened at positions shifted from the axial center of the inlet pipe , that is, inserted into different phases. The assembly phase of the fastening member is different, The cylinder body side flange part and the throttle body side flange part can be brought close to each other while securing the attachment, and the axial length of the inlet pipe can be shortened, and the throttle body connected to the upstream side of the inlet pipe Is disposed on the front side of the frame member and does not protrude to the side of the frame member, so that an increase in intake resistance due to bending of the intake passage from the intake port to the throttle body can be reduced.

  According to the intake structure of the internal combustion engine according to claim 3, the fuel injection valve provided in the inlet pipe is above the bolt mounting portion of the cylinder head side flange portion, and is one of the throttle body side flange portion. Since it is arranged adjacent to the throttle body fastening member inserted through the bolt mounting part, the fuel injection valve can be placed above the inlet pipe and can be well fastened to the throttle body side. Assembling property between the inlet pipe and the throttle body can be ensured without increasing the intake resistance.

  According to the intake structure for an internal combustion engine according to claim 4, the fuel injection valve mounting portion provided on the inlet pipe to which the fuel injection valve is fastened is inserted into the bolt mounting portion of the throttle body side flange portion. Since it is provided on the opposite side of the body fastening member and the fuel injection valve, the fuel injection valve can be well fastened and the fuel injection valve can be assembled into the inlet pipe without increasing the intake resistance of the intake passage. Sex can be secured.

  According to the intake structure for an internal combustion engine according to claim 5, the throttle body is provided with a valve shaft for rotating the throttle valve at right angles to the axial direction of the throttle body, and throttle drums are provided at both ends of the valve shaft. Since the fuel hose connected to the fuel injection valve is connected to the fuel injection valve from the opposite side of the throttle drum, the gap between the fuel hose and the throttle cable for operating the throttle drum is provided. Can be secured, and the assemblability can be improved by preventing the interference between the two members.

1 is a right side view of a motorcycle provided with an intake structure for an internal combustion engine according to an embodiment of the present invention. It is a principal part enlarged view of FIG. Fig. 2 is an enlarged plan view of a main part of the motorcycle. It is a right sectional view of an internal combustion engine. It is a principal part enlarged view of FIG. Inlet pipe, a perspective view from a substantially right-side intake port and the fuel spray area of the cylinder head. It is the perspective view seen from the substantially upper side which showed the inlet pipe, the intake port of the cylinder head, and the fuel spray area | region. It is the perspective view seen from the substantially front side which showed the inlet pipe, the intake port of the cylinder head, and the fuel spray area | region. It is IX-IX sectional drawing of FIG. It is XX sectional drawing of FIG.

  Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.

  FIG. 1 is an overall side view of a motorcycle 1 equipped with an intake structure for an internal combustion engine 10 according to the present embodiment.

  The body frame 2 of the motorcycle 1 is as follows. The main frame 2b fixed to the head pipe 2a extends rearward on the vehicle body center line so as to surround the cylinder head 13 of the internal combustion engine 10 of the motorcycle 1, and is bent downward, and the lower end of the main frame 2b A connecting member 2c oriented in the vehicle width direction is attached to the portion, and a pair of left and right lower frames 2d and 2d extend from the left and right ends of the connecting member 2c.

After the down frame 2e extends downward from the head pipe 2a at an acute angle, the lower end is fixed to the crankcase 11 of the internal combustion engine 10 .

  From the upper rear of the main frame 2b, a pair of left and right seat rails 2f, 2f extend rearward while opening left and right, and a backstay 2g connecting the center of the seat rails 2f, 2f and the lower frames 2d, 2d, 2g supports the seat rails 2f and 2f.

  In such a vehicle body frame 2, a front fork 3 is pivotally supported on the head pipe 2a, a handle 66 extending left and right is attached to an upper end of the front fork 3, a front wheel 4 is pivotally supported on the lower end, and a main frame 2b. A rear fork 5 pivotally supported at the front end by a pivot plate 2h provided at the lower portion of the rear fork extends rearward, and a rear wheel 6 is pivotally supported at the rear end thereof. The rear fork 5 and the center portion of the seat rails 2f and 2f A rear cushion 7 is interposed therebetween. A fuel tank 8 is installed on the main frame 2b, and a seat 9 is provided behind the fuel tank 8 and supported by seat rails 2f and 2f.

  The internal combustion engine 10 mounted on the vehicle body frame 2 is an SOHC type two-valve single-cylinder four-stroke internal combustion engine. The crankshaft 15 is directed in the vehicle body width direction with respect to the vehicle body, and the internal combustion engine 10 is directed from above to the rear. 10 cylinders of the internal combustion engine are slightly tilted forward so as to be surrounded by the main frame 2b, surrounded by the lower frames 2d and 2d from the rear to the bottom, and surrounded by the down frame 2e from the front to the bottom. Yes.

  As shown in FIGS. 2 and 4, in the internal combustion engine 10, a cylinder block 12 and a cylinder head 13 are sequentially stacked on a crankcase 11 and are integrally fastened by bolts (not shown). The upper part of the cylinder head 13 is covered with a head cover 14.

As shown in FIG. 4, the crankcase 11 that rotatably supports the crankshaft 15 of the internal combustion engine 10 has a left-right split crankcase structure, and the crankshaft 15 rotates in the crankcase 11. are freely supported, the speed change gear mechanism 18 to the main shaft 16 and counter shaft 17 is disposed behind the crank shaft 15 is supported, is provided between the rear wheels 6 and the counter shaft 1 The power of the crankshaft 15 is transmitted to the rear wheel 6 by a chain (not shown).

A cylinder bore 12a penetrating vertically is formed in the cylinder block 12, and a piston 19 is slidably fitted in the cylinder bore 12a so that a crank pin 15p of the crankshaft 15 is connected to the piston 19 via a connecting rod 20. It is connected with. A combustion chamber 21 is formed in the cylinder head 13, and the combustion energy in the combustion chamber 21 of the internal combustion engine 10 is converted into kinetic energy of the piston 19, whereby the piston 19 is moved up and down through the connecting rod 20. The crankshaft 15 is driven to rotate.

  As shown in FIGS. 3 and 5, the cylinder head 13 is formed with one intake valve port 22 and one exhaust valve port 23 that open on the upper wall surface of the combustion chamber 21, respectively. A spark plug hole (not shown) into which a spark plug (not shown) is inserted is opened so as to be positioned substantially at the center of the valve port 23. The intake valve port 22 and the exhaust valve port 23 communicate with an intake port 41 and an exhaust port 45 formed in the cylinder head 13, respectively.

  As shown in FIG. 3, the intake port 41 and the exhaust port 45 are formed to face each other across the cylinder axis L in plan view. The intake port 41 is formed to be gently curved in the right direction from the intake valve port 22 toward the inlet 41d of the intake port 41. The cylinder head 13 around the inlet 41d is provided with an inlet pipe 50. An intake side flange portion 13a is formed. The exhaust port 45 is formed to be curved rightward from the exhaust valve port 23 toward the outlet 45a of the exhaust port 45, and an exhaust side flange portion 13b is formed in the cylinder head 13 around the outlet 45a. An exhaust pipe 46 is connected to the exhaust side flange portion 13b.

  As shown in FIG. 5, when the longitudinal section of the internal combustion engine 10 is viewed from the right side, the intake port 41 is directed from the intake side flange portion 13 a of the cylinder head 13 toward the intake valve port 22 of the combustion chamber 21. From the rear, which is a direction that intersects with the cylinder axis L, it is gently curved toward the lower side that is along the cylinder axis L.

  The internal combustion engine 10 includes a single intake valve 25 that opens and closes the flow of intake air from the intake port 41 into the combustion chamber 21, and a single exhaust valve that opens and closes the flow of exhaust gas from the combustion chamber 21 to the exhaust port 45. 26. The intake valve port 22 is provided with an intake valve 25 for opening and closing the intake valve port 22, and the exhaust valve port 23 is provided with an exhaust valve 26 for opening and closing the exhaust valve port 23. The intake valve 25 and the exhaust valve 26 include umbrella portions 25a and 26a and shaft portions 25b and 26b, respectively. Umbrella portions 25a and 26a are valve bodies for opening and closing intake valve port 22 and exhaust valve port 23 into which valve seat 28 is press-fitted. Shaft portions 25b and 26b are disposed outward from combustion chamber 21 from umbrella portions 25a and 26a. It extends and is slidably fitted to a valve guide 29 fitted to the cylinder head 13.

  The shaft end portions 25 c and 26 c of the intake valve 25 and the exhaust valve 26 protrude above the valve guide 29, and the shaft end portions 25 c and 26 c are held by the spring retainer 30. Between the spring retainer 30 and the spring receiving member 31 supported by the cylinder head 13 so as to face the spring retainer 30, a coil shape is formed so as to surround the shaft portion 25b of the intake valve 25 and the shaft portion 26b of the exhaust valve 26. A valve spring 32 is attached in a compressed state, and the intake valve 25 and the exhaust valve 26 are always urged in the valve closing direction by the coiled valve spring 32.

  A valve operating device 35 for opening and closing the intake valve 25 and the exhaust valve 26 is provided in the head cover 14. The valve operating device 35 employs a rocker arm type SOHC type, and a pair of rocker arm shafts 39 that rotatably supports the cam shaft 36, the intake rocker arm 37, the exhaust rocker arm 38, and the intake rocker arm 37 and the exhaust rocker arm 38. And. The camshaft 36 is provided with a driven gear (not shown) so as to rotate together.The driven gear and a driving gear (not shown) rotated together with the crankshaft 15 are connected to a cam chain (not shown). (Not shown) is spanned, and the camshaft 36 is rotated as the crankshaft 15 rotates. As the camshaft 36 rotates, the intake rocker arm 37 and the exhaust rocker arm 38 are swung at a predetermined timing. The pressing portion 37a of the intake rocker arm 37 is the shaft end 25c of the intake valve 25, and the end 38a of the exhaust rocker arm 38 is the exhaust valve. The shaft end portions 26c of the 26 are respectively pushed and the intake valve port 22 and the exhaust valve port 23 are opened and closed at a predetermined timing.

  As shown in FIGS. 2 to 5, the intake structure 40 of the internal combustion engine 10 is configured so that the outside air taken in from the air cleaner 58 includes an intake port 41, an inlet pipe 50, a throttle body 55, and a connecting tube 57 of the cylinder head 13. The sprayed fuel that is sent from the upstream side of the intake air into the intake passage P that is sequentially connected and injected from the fuel injection valve 54 inserted into the inlet pipe 50 in the middle of the intake passage P is mixed to form an air-fuel mixture. The gas is supplied into the port 41 and sent to the combustion chamber 21.

  As shown in FIG. 3, the inlet pipe 50 is connected to the inlet 41d of the intake port 41 that is gently curved from the intake valve port 22 toward the rear right side in the cylinder axis L direction view, that is, in the top view in this embodiment. The throttle valve 56 is connected obliquely rearward to the right side so as to be continuous with the flow direction center line of the intake port 41.

  As shown in FIGS. 2 and 3, the inlet pipe 50 and the throttle valve 56 are disposed so as to be located in front of the portion of the main frame 2b located behind the internal combustion engine 10, that is, FIG. As shown in FIG. 2, the vehicle is disposed so as to be positioned between the internal combustion engine 10 and the main frame 2b in a side view, so that the vehicle is not disposed on the side of the main frame 2b disposed at the center in the vehicle width direction. It can be stored compactly in the width direction.

  As shown in FIGS. 1 to 3, the air cleaner 58 into which outside air is taken is located substantially in the center with respect to the vehicle width direction, and includes a seat rail 2 f that extends rearward from the main frame 2 b and rearward from the main frame 2 b. It is disposed in a space surrounded by the main frame 2b, the seat rail 2f, and the back stay 2g so as to be located below the back stay 2g. The outside air taken from the rear of the vehicle is filtered for impurities in the air cleaner 58.

  As shown in FIG. 3, the outlet 57a of the air cleaner 58 is provided on the right side of the front side, and the outlet 57a is connected to the upstream side of the connecting tube 57 made of resin. Further, the connecting tube 57 is curved and is connected to the upstream side of the throttle body 55 so as to bypass the main frame 2 b of the main frame 2 b located behind the internal combustion engine 10.

  As shown in FIG. 5, the intake passage P is formed by a partition wall 70 including an intake port partition wall 71 formed in the intake port 41 and an inlet pipe partition wall 72 formed in the inlet pipe 50. It is divided into an intake passage Up and a lower intake passage Lp, and a ratio of intake air flowing through the upper intake passage Up and the lower intake passage Lp can be changed by a flap 73 provided in the throttle body 55. It has become. A fuel injection valve 54 is disposed in the inlet pipe 50 so as to inject fuel toward the upper intake passage Up that is upstream of the intake port 41 and outside the curve of the intake passage P.

  6 to 8, in the intake passage P, the intake port 41 of the cylinder head 13, the intake port partition wall 71, the inlet pipe 50, the fuel injection valve 54, and the fuel spray sprayed from the fuel injection valve 54 are roughly shown. The fuel spray region F, which is the region of FIG. 2, is shown, the cylinder head 13 is omitted, the boundary between the cylinder head 13 and the intake port 41, the intake port partition wall 71, the fuel injection valve 54 and the inlet pipe 50 are provided. It is indicated by a solid line, and the fuel spray area F is indicated by an area surrounded by a two-dot chain line and hatched by dots.

As shown in FIG. 3, the intake port 41 formed in the cylinder head 13 is gently moved rightward from the intake valve port 22 toward the inlet 41 d of the intake port 41 when viewed from the direction along the cylinder axis L. It is formed to be curved, and the inlet 41d is formed to be inclined rearward to the outlet 57a of the connecting tube 57. Further, as shown in FIG. 7, it is sprayed from the fuel injection valve 54 of the inlet pipe 50. The sprayed fuel is formed in a gently curved shape so as to go from the inlet 41d of the intake port 41 to the intake valve port 22 serving as the outlet of the intake port 41. Further, as shown in FIG. 5, when the longitudinal section of the internal combustion engine 10 is viewed from the right side, the intake port 41 extends from the intake side flange portion 13 a of the cylinder head 13 toward the intake valve port 22 of the combustion chamber 21. From the rear, which is the direction intersecting the axis L, it is gently curved toward the lower side, which is the direction along the cylinder axis L.

  As shown in FIGS. 5 and 9, the intake port 41 is vertically divided into an upper passage 41 a and a lower passage 41 b by an intake port partition wall 71 formed integrally with the cylinder head 13. 9 is a cross-sectional view of the cylinder head 13 on the downstream side of the intake port, and is a cross-sectional view taken along the line IX-IX in FIG. FIG. 10 is a cross-sectional view of the region upstream of the intake port of the cylinder head 13 and in which a fuel dome chamber 42 described later is formed on the upper wall 41c, and is a cross-sectional view taken along the line XX in FIG. The intake port partition wall 71 is integrally formed in the intake port 41 so as to be offset upward so that the passage area of the upper passage 41a is smaller than that of the lower passage 41b. Even when the operation region is operated, the flow rate of the air-fuel mixture flowing into the upper passage 41a is increased by the flap 73 provided in the throttle body 55, and the passage area of the upper passage 41a is reduced. Since the flow rate of the air-fuel mixture flowing into the combustion chamber 21 from the passage 41a can be increased, the generation of tumble is promoted and the combustion efficiency in the combustion chamber 21 is improved.

The downstream end portion 71a of the intake port partition wall 71 has cutout recess 71b at the center is formed, since the cutout recess 71 in b the shaft portion 25b of the intake valve 25 can penetrate, intake port partition walls 71 The downstream end portion 71a extends beyond the valve axis 25d, which is the longitudinal axis of the intake valve 25, to the downstream side without being blocked by the shaft portion 25b of the intake valve 25. Since the intake port partition wall 71 extends to substantially the center of the combustion chamber 21 in this way, the flap 73 in the throttle body 55 is closed when the internal combustion engine 10 is operated in an operation region at a relatively low rotational speed. Since the air-fuel mixture is supplied through the curved outer upper passage 41a to the substantially center of the combustion chamber 21, the vortex flow with strong tumble is generated in the combustion chamber 21, and the air and fuel Is promoted to improve combustion, and the fuel efficiency and output of the internal combustion engine 10 are improved.

  As shown in FIGS. 6 to 8, the fuel dome chamber 42 in which the sprayed fuel injected from the fuel injection valve 54 diffuses and promotes vaporization on the upper wall 41 c on the upstream side of the intake port 41. Is formed. The fuel dome chamber 42 is formed to be gently curved rightward along the curvature of the intake port 41. The fuel dome chamber 42 has a groove-like recess 43 formed in a semi-cylindrical groove so as to avoid and surround the outer edge of the fuel spray region F from the fuel injection valve 54 disposed on the upstream side of the intake port 41; On the downstream side of the intake port 41, a dome-shaped dome portion 44 is connected to the groove-shaped recess 43 and is extended a predetermined distance in the axial direction of the intake port 41.

  As shown in FIG. 10, the groove-like recess 43 is narrower than the width of the upper passage 41 a and is located above the upper passage 41 a of the intake port 41 so as to avoid the fuel spray region F from the fuel injection valve 54. As shown in FIG. 6, it is formed to have a length of about one third of the axial length of the upper passage 41a.

  The dome-shaped portion 44 is formed in a dome shape that continues from the groove-shaped concave portion 43 toward the upstream direction and extends in a length slightly shorter than the groove-shaped concave portion 43 in the axial direction of the intake port 41 while gradually decreasing in height. As shown in FIG. 5, the tip 44 a of the dome 44 extends to the vicinity of the valve guide 29 of the intake valve 25.

  As shown in FIGS. 6 to 8, since the groove-like recess 43 is formed so as to avoid the outer edge of the fuel spray region F injected from the fuel injection valve 54, the sprayed fuel is transferred to the groove-like recess 43. The intake port 41 is further expanded upward by the fuel dome chamber 42 than the normal intake port, and the valve guide of the intake valve 25 in the length direction is also prevented. Since it is expanded to the vicinity of 29, the atomized fuel can be diffused in the fuel dome chamber 42 to promote atomization, and further the vaporization of the atomized fuel can be promoted.

  Further, as shown in FIGS. 9 and 10, the cross-sectional area of the upper passage 41a in the region where the fuel dome chamber 42 is formed is larger than the passage cross-sectional area of the upper passage 41a on the downstream edge side, The flow rate of the air-fuel mixture passing through the upper passage 41a can be increased from the upstream side toward the downstream side.

An inlet pipe 50 provided with a fuel injection valve 54 is connected to the upstream side of the intake port 41 of the cylinder head 13. The inlet pipe 50 is connected to the throttle body 55 on the upstream side, and is a fuel injection valve so as to inject fuel toward the upper intake passage Up that is upstream of the intake port 41 and outside the curve of the intake passage P. 54 is arranged.

  As shown in FIG. 5 and FIG. 6, the inlet pipe 50 includes a pipe portion 51 having an inside serving as an intake passage P, and a cylinder head side flange portion formed on both ends of the pipe portion 51 and attached to the cylinder head 13. 52, a throttle body side flange portion 53 attached to the throttle body 55, and an inlet pipe partition wall 72 that partitions the inside of the pipe portion 51 in the vertical direction.

  As shown in FIGS. 5 and 6, the pipe portion 51 has a fuel injection valve mounting portion through which the fuel injection valve 54 is inserted so as to protrude above the pipe portion 51 and continue to the cylinder head side flange portion 52. 51a is formed. The fuel injection valve mounting portion 51a has a fuel injection valve so as to penetrate a part of the cylinder head side flange portion 52 from the upper surface toward the obliquely downward direction of the pipe portion 51 and communicate with the upper intake passage Up. An insertion hole 51b is formed. As shown in FIGS. 7 and 8, the pipe portion 51 is formed with a fuel injection valve mounting portion 51 c that protrudes upward on the left side and fixes the fuel injection valve 54.

  As the fuel injection valve 54 inserted into the fuel injection valve insertion hole 51b of the inlet pipe 50, a fuel injection valve of a type that deflects and injects with an offset angle with respect to the main shaft is used. The main body portion 54a of the fuel injection valve 54 has a substantially cylindrical shape, and an injection port 54c for injecting fuel is formed at the distal end portion 54b of the main body portion 54a. A mounting portion 54e for fixing to the inlet pipe 50 is formed to protrude in the upper left direction at the base end portion 54d opposite to the injection port 54c in the main body portion 54a.

Further, as shown in FIG. 3, a fuel hose connecting portion 54g for connecting a fuel hose 65 connected to the fuel tank 8 and fed with fuel is projected to the left at the base end portion 54d of the fuel injection valve 54. The fuel stored in the fuel tank 8 is sent to the fuel injection valve 54 via the fuel hose 65.

  Further, as shown in FIGS. 2 and 6, an electrical connection portion 54h to which a cable (not shown) for sending a signal from an ECU (not shown) is attached is formed upward from the base end portion 54d. A signal for opening and closing the fuel injection valve 54 is sent from the ECU to the fuel injection valve 54 via a cable.

  As shown in FIG. 8, a bolt insertion hole 54 f into which the fuel injection valve mounting bolt 61 is inserted is formed in the mounting portion 54 e of the fuel injection valve 54. After the fuel injection valve 54 is inserted into the fuel injection valve insertion hole 51b, the bolt insertion hole 54f of the attachment portion 54e of the fuel injection valve 54 and the bolt insertion hole 51d of the fuel injection valve attachment portion 51c of the inlet pipe 50 are The fuel injection valve mounting bolt 61 is inserted, fastened by the nut 62, and fixed to the inlet pipe 50. As shown in FIG. 5, the fuel injection valve 54 attached to the inlet pipe 50 is arranged on the upstream side of the upper passage 41 a of the intake port 41, and the intake port 41 that is outside the curve in the side view of the intake port 41. Fuel is injected in the downstream direction of the upper passage 41a.

  As shown in FIG. 8, a pair of bolt mounting portions 52a are formed on the cylinder head side flange portion 52 so as to protrude in the left-right direction at right angles to the axial center of the inlet pipe 50. Bolt insertion holes 52b are formed in the respective parts 52a. A cylinder head mounting bolt 59 is inserted into the bolt insertion hole 52b of the pair of bolt mounting portions 52a and is screwed into a bolt hole (not shown) formed in the cylinder head 13, so that the inlet pipe 50 is mounted to the cylinder head 13. It is done.

The throttle body side flange portion 53 is formed with a pair of bolt mounting portions 53 a that project obliquely up and down at right angles to the axial center of the inlet pipe 50. The bolt mounting portion 53a of the throttle body side flange portion 53 and the bolt mounting portion 52a of the cylinder head side flange portion 52 are formed at positions shifted from the axial center of the inlet pipe 50, that is, at different phases . Bolt insertion holes 53b are formed in the pair of bolt mounting portions 53a, respectively. The throttle body mounting bolt 60 is inserted into the bolt insertion hole 53b of the bolt mounting portion 53a and is screwed into a bolt hole (not shown) formed in the throttle body 55 so that the inlet pipe 50 and the throttle body 55 are connected.

Thus, the cylinder head mounting bolts 59, the bolt mounting portions 53a of the throttle body side flange portion 53, because it is fastened is inserted in a position shifted with respect to the axial center of the inlet pipe 50, the pipe portion 51 Even if the axial length is shortened, the screwing of the cylinder head mounting bolt 59 to the cylinder head 13 and the screwing of the throttle body mounting bolt 60 to the throttle body 55 are not hindered.

  As shown in FIG. 8, the fuel injection valve 54 provided in the inlet pipe 50 includes one throttle body mounting bolt 60 that is above the cylinder head side flange portion 52 of the pair of throttle body mounting bolts 60, That is, in the present embodiment, it is disposed adjacent to the right throttle body mounting bolt 60a located on the right side, so that the fuel injection valve 54 is disposed upward and the fastening with the throttle body 55 can be satisfactorily performed. .

  A fuel injection valve mounting portion 51c provided on the inlet pipe 50 and to which the fuel injection valve 54 is fastened includes a right throttle body mounting bolt 60a positioned on the right side inserted through the throttle body side flange portion 53, and a fuel injection valve 54. It is provided on the opposite side, so that it can be easily engaged with the fuel injection valve 54 and the increase in intake resistance can be reduced.

As shown in FIG. 5, the throttle body 55 has a cylindrical shape, connected to the upstream side of the inlet pipe 50, a butterfly type throttle valve 56 for opening and closing limiting the intake air amount therein a valve shaft 56a It is attached so as to rotate as a center.
The valve shaft 56a is rotatably supported on the throttle body 55 so as to be oriented at right angles to the axial direction of the throttle body 55.

  As shown in FIG. 3, a throttle drum 63 that opens and closes the throttle valve 56 by rotating the valve shaft 56 a is disposed on the right side of the throttle body 55. A throttle valve opening sensor 64 for detection is provided. Both ends of the valve shaft 56a pass through the throttle body 55 and project outside the throttle body 55. A throttle drum 63 is connected to the right end 56b, and a throttle valve opening sensor 64 is connected to the left end 56c. Has been. The fuel hose 65 connected to the fuel injection valve 54 is connected to the fuel injection valve 54 from the opposite side of the throttle drum 63, and a clearance between the fuel hose 65 and a throttle cable 68 described later is secured, so that assembly work is easy. become.

  The throttle drum 63 includes a spring (not shown) that urges the throttle valve 56 in the closing direction, and an opening cable 68a to which the throttle drum 63 and a throttle grip 67 provided on the handle 66 are connected and a closing valve. The throttle valve 56 is rotated in the opening direction or the closing direction and the throttle valve 56 is opened and closed by the operation of the throttle grip 67 by the passenger via the throttle cable 68 including the cable 68b.

  The throttle drum 63 and the flap shaft 73a that rotates the flap 73 are connected by a link mechanism (not shown), and the flap drum is rotated by a predetermined rotation amount as the throttle drum 63 rotates. Thus, the opening of the flap is determined according to the opening of the throttle valve 56, and the ratio of the intake air to the upper intake passage Up and the lower intake passage Lp of the intake passage P is changed.

  Since the intake structure 40 of the saddle-ride type vehicle according to this embodiment is configured as described above, the intake port 41 of the cylinder head 13 has an inlet 41d of the intake port 41 connected to the connecting tube 47 when viewed in the cylinder axis L direction. Inclined toward the outlet 57a and has a gently curved shape so that the fuel spray from the fuel injection valve 54 is directed from the inlet 41d of the intake port 41 to the intake valve port 22 which is the outlet of the intake port 41. Thus, the intake resistance in the intake port 41 can be reduced, and the fuel sprayed from the fuel injection valve 54 is reduced from adhering to the inner wall of the intake port 41. Further, the throttle body 55 and the inlet pipe 50 are disposed in front of the vehicle body with respect to the main frame 2b behind the internal combustion engine 10, and the connecting tube 57 is curved so as to bypass the main frame 2b behind the internal combustion engine 10 to be throttled. , The throttle valve 56 can be brought closer to the vehicle body center line without affecting the degree of freedom of the frame shape, and the bending of the intake passage P from the intake port 41 to the throttle valve 56 can be reduced. Thus, the intake resistance can be further reduced, the performance of the internal combustion engine 10 can be improved, and the output and fuel consumption can be improved.

  Further, the inlet pipe 50 is provided with a cylinder head side flange portion 52 and a throttle body side flange portion 53 at the front and rear end portions of the pipe portion 51, and a pair of cylinder head side flange portion 52 and throttle body side flange portion 53 are respectively provided. Are attached to the cylinder head 13 by a cylinder head mounting bolt 59 inserted into the mounting portion 52a of the cylinder head side flange 52. The throttle body 55 is fastened to the throttle body 55 by a throttle body mounting bolt 60 inserted into the mounting portion 53a of the throttle body side flange 53. The cylinder head mounting bolt 59 and the throttle body mounting bolt 60 are connected to the axial center of the inlet pipe 50. Assemble each bolt as it is inserted and fastened It is possible to reduce the axial length of the inlet pipe 50 by bringing the cylinder head side flange portion 52 and the throttle body side flange portion 53 closer to each other while ensuring the ease of assembly while maintaining the assembly phase. 50, the throttle body 55 connected to the upstream side of the main frame 2b is disposed on the front side of the main frame 2b so as not to protrude to the side of the main frame 2b, so that the intake passage P from the intake port 41 to the throttle body 55 An increase in intake resistance due to bending can be reduced.

  The fuel injection valve 54 attached to the inlet pipe 50 is above the bolt mounting portion 52a of the cylinder head side flange portion 52 and is inserted into one bolt mounting portion 53a of the throttle body side flange portion 53. Since it is disposed adjacent to the throttle body mounting bolt 60, the fuel injection valve 54 is disposed above the inlet pipe 50 and can be well fastened to the throttle body 55 side. Assembly of the inlet pipe 50 and the throttle body 55 can be ensured without increasing the resistance.

Furthermore, the fuel injection valve mount portion 51 c of the inlet pipe 50 to the fuel injection valve 54 is concluded, and one throttle body mounting bolts 60 that are inserted into the bolt mounting portion 53a of the throttle body side flange portion 53, the fuel injection Since it is provided on the opposite side across the valve 54, the fuel injection valve 54 can be well fastened to the inlet pipe 50, and the intake pipe P of the fuel injection valve 54 can be increased without increasing the intake resistance of the intake passage P. Assembling property can be ensured.

  The throttle body 55 is provided with a valve shaft 56a for rotating the throttle valve 56 at a right angle to the axial direction of the throttle body 55. A throttle drum 63 and a throttle valve opening sensor 64 are provided at both ends of the valve shaft 56a. The fuel hose 65 connected to the fuel injection valve 54 is connected to the fuel injection valve 54 from the opposite side of the throttle drum 63, so that the throttle cable 68 for operating the fuel hose 65 and the throttle drum 63 is provided. It is possible to secure a clearance between the two members, and it is possible to prevent the interference between the two members and improve the assemblability.

  The intake structure of the internal combustion engine according to the embodiment of the present invention has been described above, but the aspect of the present invention is not limited to the above-described embodiment, and includes those implemented in various aspects within the scope of the present invention. It is a waste.

  L ... cylinder axis, 1 ... motorcycle, 2 ... body frame, 2b ... main frame, 10 ... internal combustion engine, 13 ... cylinder head, 25 ... intake valve, 25b ... valve shaft, 29 ... valve guide, 41 ... intake port, 41d: inlet, 42 ... fuel dome chamber, 43 ... concave groove, 44 ... dome, 44a ... tip, 50 ... inlet pipe, 52 ... Linder head side flange, 52a ... bolt mounting part, 53 ... throttle body side Flange portion, 53a ... bolt mounting portion, 54 ... fuel injection valve, 55 ... throttle body, 56 ... throttle valve, 56a ... valve shaft, 57 ... connecting tube, 57a ... outlet, 59 ... cylinder head fastening member, 60 ... throttle body Fastening member, 60a ... throttle body fastening member, 61 ... throttle drum, 62 ... opening sensor, 63 ... fuel hose.

Claims (5)

In the intake structure of the saddle-ride type vehicle (1) having a frame member (2b) arranged on the vehicle body center line so as to surround the cylinder head (13) of the internal combustion engine from the upper side to the rear side of the internal combustion engine (10),
The intake structure is
An inlet pipe (50) provided with a fuel injection valve (54) and connected to an intake port (41) of a cylinder head (13) of the internal combustion engine (10);
A throttle body (55) connected to the upstream side of the inlet pipe (50) and restricting the intake air amount by a throttle valve (56);
A connecting tube (57) connected to the upstream side of the throttle body (55),
The intake port (41) of the cylinder head (13) is arranged such that the inlet (41d) of the intake port (41) faces the outlet (57a) of the connecting tube (57) when viewed in the cylinder axis (L) direction. The sprayed fuel sprayed from the fuel injection valve (54) of the inlet pipe (50) from the inlet (41d) of the intake port (41) to the outlet (22) of the intake port (41) Is formed in a gently curved shape,
The throttle body (55) and the inlet pipe (50) are disposed on the front side of the vehicle body from the frame member (2b) behind the internal combustion engine (10),
The connecting tube (57) is curved so as to bypass the frame member (2b) behind the internal combustion engine (10) and is connected to the throttle body (55). Intake structure. The inlet pipe (50) is provided with a cylinder head side flange portion (52) on the cylinder head (13) side, and a throttle body side flange portion (53) on the throttle body side,
The cylinder head side flange portion (52) and the throttle body side flange portion (53) are each formed with a pair of bolt mounting portions (52a), (53a) projecting perpendicularly to the central axis of the inlet pipe. ,
The inlet pipe (50) is fastened to the cylinder head (13) by a cylinder head fastening member (59) inserted through the bolt mounting portion (52a), and is inserted into the bolt mounting portion (53a). Fastened with the throttle body (55) by the fastening member (60),
The said cylinder head fastening member (59) and the said throttle body fastening member (60) are penetrated in the position shifted | deviated with respect to the axial center of the said inlet pipe (50). Intake structure for saddle-ride type vehicles. The fuel injection valve (54) provided in the inlet pipe (50),
Above the bolt mounting portion (52a) of the cylinder head side flange portion (52),
The said throttle body fastening member (60a) arrange | positioned adjacent to the said bolt attachment part (53a) of one side of the said throttle body side flange part (53), It arrange | positions adjacently. The intake structure of a saddle-ride type vehicle. The fuel injection valve mounting portion (51c) provided in the inlet pipe (50) and fastened with the fuel injection valve (54)
One throttle body fastening member (60a) inserted through the bolt mounting portion (52a) of the throttle body side flange portion (52), and provided on the opposite side across the fuel injection valve (54) The intake structure for a saddle-ride type vehicle according to claim 3. The throttle body (55) is provided with a valve shaft (56a) for rotating the throttle valve (56) at a right angle to the axial direction of the throttle body (55),
A throttle drum (61) and an opening sensor (62) are provided at both ends of the valve shaft (56a),
The fuel hose (63) connected to the fuel injection valve (54) is connected to the fuel injection valve (54) from the opposite side of the throttle drum (61). Intake structure for saddle-ride type vehicles.

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