WO2017110321A1

WO2017110321A1 - Vaporizer

Info

Publication number: WO2017110321A1
Application number: PCT/JP2016/084045
Authority: WO
Inventors: 知幸千田; 崇後藤; 鈴木　祥介; 信弘島田; 飯室　昭宏
Original assignee: 本田技研工業株式会社
Priority date: 2015-12-25
Filing date: 2016-11-17
Publication date: 2017-06-29
Also published as: JP2017115737A

Abstract

A vaporizer (11) is provided with: a shared path (46); a main air bleed path (43) and a slow air bleed path (45) which are individually connected to the shared path (46); a first valve body (47a) which changes, in the shared path (46), the opening area of the main air bleed path (43); driving-force transmission mechanisms (49, 51) which drive the first valve body (47a); and a second valve body (47b) which changes, in the shared path (46), the opening area of the slow air bleed path (45) in conjunction with the first valve body (47a). Accordingly, the vaporizer in which the main air bleed path and the slow air bleed path can be controlled and the structures of the valve bodies can be simplified can be provided.

Description

Vaporizer

The present invention relates to a vaporizer.

Patent Document 1 discloses a vaporizer having a main air bleed passage and a slow air bleed passage. The main air bleed passage and the slow air bleed passage merge at the intake passage. A valve element is disposed in each air bleed passage. The valve body adjusts the opening area of each air bleed passage.

Japanese Unexamined Patent Publication No. 8-296504

In the vaporizer described in Patent Document 1, since a common path is not formed, the valve bodies cannot be shared. Since the main air bleed passage and the slow air bleed passage are independent, the structure of the valve body cannot be simplified.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a carburetor capable of controlling the main air bleed passage and the slow air bleed passage and simplifying the structure of the valve body.

According to the first aspect of the present invention, the common path, the main air bleed passage and the slow air bleed passage individually connected to the common path, and the opening area of the main air bleed passage in the common path are changed. A valve body; a driving force transmission mechanism that drives the first valve body; and a second valve body that changes an opening area of the slow air bleed passage in the common path while interlocking with the first valve body. A vaporizer is provided.

According to the second side, in addition to the configuration of the first side, the first valve body and the second valve body are integrated.

According to the third aspect, in addition to the configuration of the second side surface, a slide surface that faces the space of the common path is defined, and the slide surface opens to either the main air bleed passage or the slow air bleed passage. A first opening to be connected, and a passage hole having a second opening that opens at the slide surface and is connected to the other of the main air bleed passage and the slow air bleed passage, and the first and second valve bodies include: A first partition that overlaps the first opening according to a sliding operation and a second partition that overlaps the second opening according to a sliding operation are partitioned.

According to the fourth aspect, in addition to the configuration of the third side surface, a screw mechanism is used for the driving force transmission mechanism, and the driving force transmission mechanism, the first opening, and the second opening are aligned in one direction. Provided.

According to the fifth aspect, in addition to the configuration of the third or fourth side surface, the first or second partition is formed on an outer edge of the first and second valve bodies.

According to the first aspect, the main air bleed passage is particularly used when the engine negative pressure is weak (high load), and the slow air bleed passage is particularly used when the engine negative pressure is strong (low load). The slow air bleed valve body and the main air bleed valve body can be arranged on the common path. Therefore, the structure of the valve body can be simplified.

According to the second aspect, since the first valve body and the second valve body are integrated, the first valve body and the second valve body can be formed as one member. Therefore, an increase in the number of parts is avoided. The burden of assembly work is reduced. Moreover, a valve body can be formed compactly.

According to the third aspect, the first partition of the valve body is displaced with respect to the first opening to change the opening area of the main air bleed passage or the slow air bleed passage. Similarly, the second partition of the valve body is displaced with respect to the second opening and changes the other opening area of the main air bleed passage or the slow air bleed passage. The opening of the main air bleed passage and the opening of the slow air bleed passage are finely controlled in accordance with the sliding operation of the valve body. Further, since the opening area of the slide surface is changed, the valve body has a simple structure, and the valve body can be made compact.

According to the fourth aspect, a screw mechanism extending in one direction can be easily provided along the one direction. Since the direction other than one direction becomes compact (downsizing), the passage hole can be installed in the vaporizer so that the vaporizer becomes compact.

According to the fifth aspect, it can be made compact in one direction.

FIG. 1 is a vertical sectional view schematically showing the overall configuration of a vaporizer according to a first embodiment of the present invention. FIG. 2 is a vertical sectional view taken along line 2-2 in FIG. FIG. 3 is a vertical sectional view taken along line 3-3 in FIG. FIG. 4 is an enlarged vertical sectional view of a passage hole functioning as a common of the main air bleed passage and the slow air bleed passage. FIG. 5 is an enlarged vertical sectional view of the passage hole observed from another angle. FIG. 6 is an enlarged partial vertical sectional view schematically showing a part of the vaporizer according to the second embodiment and the third embodiment.

11 ... carburetor 43 ... main air bleed passage 43a ... second opening 45 ... slow air bleed passage 45a ... first opening 46 ... common passage (passage hole)
46b ... slide surface 47a ... first valve element 47b ... second valve element 49 ... drive shaft 51 as one component of the driving force transmission mechanism ... electric motor 56a as one component of the driving force transmission mechanism ... first partition 57a ... second partition 57 ... outer edge

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

First, FIG. 1 schematically shows the entire vaporizer 11 according to the first embodiment of the present invention. The vaporizer 11 includes a vaporizer body 12. The carburetor body 12 has a body 13 and a valve cylinder 14. The carburetor body 12 defines an intake passage 15 in the body 13. Air is introduced into the intake passage 15 from an intake port 15a. Vaporized fuel is mixed with air in the intake passage 15 of the carburetor 11. The air-fuel mixture thus generated is discharged from the discharge port 15b. Such a carburetor 11 can be used by being incorporated in a saddle type vehicle such as a motorcycle. For example, an intake duct (not shown) leading to an air cleaner may be connected to the intake port 15a of the intake passage 15 for mounting on a motorcycle, and the exhaust port 15b of the intake passage 15 is connected to, for example, an intake port of an internal combustion engine. An intake pipe (not shown) may be connected.

The valve cylinder 14 is integrated with the body 13. The carburetor body 12 defines a slide space 16 that branches from an intake passage 15 extending in the horizontal direction within the valve cylinder 14. Here, the slide space 16 is shaped like a cylinder having a central axis 17 b orthogonal to the central axis 17 a of the intake passage 15. A storage chamber 18 is formed in the vaporizer body 12 around the valve cylinder 14.

The carburetor body 12 accommodates a piston-shaped throttle valve 19 in the valve cylinder 14. The throttle valve 19 is slidably fitted in and accommodated in the slide space 16. The throttle valve 19 opens and closes the intake passage 15 according to the vertical movement of the throttle valve 19. The opening degree of the intake passage 15 is adjusted according to the position of the throttle valve 19.

A throttle cable 21 is connected to the throttle valve 19. The throttle cable 21 is connected to, for example, a throttle grip (not shown) of a motorcycle. The operation of the throttle grip is converted into the movement of the throttle cable 21 in the axial direction. The flow rate and mixture ratio of the air-fuel mixture are adjusted according to the operation of the throttle cable 21.

A first lid member 22 is attached to the vaporizer body 12. The first lid member 22 covers the open end of the storage chamber 18 at the upper end of the vaporizer body 12. A fastening member, that is, a bolt 23 is used for attachment. The first lid member 22 is detachably coupled to the vaporizer body 12 with, for example, a plurality of bolts 23. The first lid member 22 is formed with an opening 22 a that allows the throttle valve 19 to enter and exit the storage chamber 18. The opening 22 a has a circular outline coaxial with the axis of the throttle cable 21. The first lid member 22 is formed with a boss 22b surrounding the opening 22a. A male screw 24 is engraved on the outer peripheral surface of the boss 22b.

The second lid member 25 is detachably attached to the first lid member 22. The throttle cable 21 passes through the second lid member 25. The second lid member 25 has a circular outline concentric with the axis of the throttle cable 21. The second lid member rotates with respect to the first lid member 22 around the rotation axis that overlaps the axis of the throttle cable 21. The rotation axis overlaps the center axis 17b. A female screw 26 is engraved on the inner peripheral surface of the second lid member 25. The female screw 26 of the second lid member 25 meshes with the male screw 24 of the first lid member 22. Thus, the second lid member 25 is screwed to the first lid member 22.

A string spring 27 is disposed between the throttle valve 19 and the second lid member 25. The string spring 27 is sandwiched between the throttle valve 19 and the second lid member 25 and exhibits a repulsive force in the extending direction. Accordingly, the string spring 27 pushes down the throttle valve 19 toward the lowest position. The throttle valve 19 at the lowest position establishes a minimum opening (for example, an idle operation opening state) in the intake passage 15. When the throttle cable 21 is pulled and the throttle valve 19 is displaced upward against the repulsive force of the string spring 27, the opening of the intake passage 15 increases.

In the intake passage 15, a choke valve 28 is disposed upstream of the throttle valve 19. The choke valve 28 is configured as a so-called butterfly type. The choke valve 28 rotates about an axis extending in the horizontal direction, and opens and closes the intake passage 15 according to the rotation. The choke valve 28 is used to increase the fuel ratio at start-up.

A float chamber body 29 is coupled to the lower end of the vaporizer body 12. The float chamber body 29 partitions the float chamber 31 between the vaporizer body 12. The float chamber 31 accommodates a float 32 having a specific gravity smaller than that of the fuel. The float 32 moves up and down according to the fuel level. A support plate 33 is coupled to the float 32. The support plate 33 is disposed in the float chamber 31 so as to be swingable around the support shaft 34. The support plate 33 supports the float valve 35 from below. The float valve 35 closes the fuel inflow path 36 at a predetermined liquid level. When the fuel level drops, the float valve 35 opens. The fuel flows into the float chamber 31 from the fuel inflow passage 36 in response to opening of the valve. In this way, the fuel that forms the oil level at a constant liquid level is always stored in the float chamber 31. A fuel conduit extending from the fuel tank is connected to the fuel inflow path 36. Fuel is supplied to the fuel inflow path 36 from a fuel tank.

In the float chamber 31, a main jet 37 and a slow jet 38 are arranged in parallel. A main nozzle 39 that opens to the intake passage 15 is connected to the main jet 37. The fuel is measured by the main jet 37 and ejected from the main nozzle 39. The slow jet 38 is connected to a slow nozzle 41 that opens to the intake passage 15 downstream of the main nozzle 39. The fuel is measured by the slow jet 38 and ejected from the slow nozzle 41. The ejection of fuel is set by the opening area of the slow nozzle 41.

The needle valve 42 is connected to the throttle valve 19. The needle valve 42 is disposed coaxially with the throttle valve 19, protrudes downward from the lower end of the throttle valve 19, and is set so that the diameter decreases toward the lower side. The needle valve 42 is inserted into the main nozzle 39. The needle valve 42 moves up and down in the main nozzle 39 according to the vertical movement of the throttle valve 19. The up and down movement changes the opening area of the main nozzle 39 to set the ejection of fuel.

As shown in FIG. 2, a main air bleed passage 43 is formed in the vaporizer body 12. The second passage 43c of the main air bleed passage 43 opens to the

main nozzle portions

37 and 39 at the tip. The second path 43c is formed by a drill hole inclined downward. The outer end of the second path 43c is closed by a closing member 44a fitted into the vaporizer body 12. Here, the main air bleed passage 43 faces the

main nozzle portions

37 and 39 facing the intake passage 15 on one side with respect to a plane VP including the center line 17a of the intake passage 15 and the center line 17b of the valve cylinder 14. It functions as the 1st connection path extended.

3, a slow air bleed passage 45 is formed in the vaporizer body 12. The fourth passage 45c of the slow air bleed passage 45 opens to the slow nozzle portions 38 and 41 at the tip. The fourth path 45c is formed by a drill hole inclined downward. The outer end of the fourth path 45c is closed by a closing member 44b fitted into the vaporizer body 12. Here, the slow air bleed passage 45 faces the slow nozzle portions 38 and 41 facing the intake passage 15 on one side with reference to a plane VP including the center line 17a of the intake passage 15 and the center line 17b of the valve cylinder 14. It functions as the 2nd connection path extended.

4, a passage hole 46 having two air bleed passages (a main air bleed passage 43 and a slow air bleed passage 45) is formed in the vaporizer body 12. The main air bleed passage 43 and the slow air bleed passage 45 are individually connected to the passage hole 46. The main air bleed passage 43 and the slow air bleed passage 45 extend on one side where the passage hole 46 is disposed with reference to a plane VP including the center line 17a of the intake passage 15 and the center line 17b of the valve cylinder 14. The choke valve 28 is disposed on the other side from the choke valve 28 to the operation lever 60 (see FIG. 2). The passage hole 46 defines a cylindrical space having a central axis extending in a direction in which gravity acts (here, a vertical direction). The central axis of the passage hole 46 extends in the direction in which the valve cylinder 14 extends in a direction perpendicular to the intake path direction (direction in which the intake path 15 extends) and in the valve cylinder direction (direction in which the valve cylinder 14 extends). Yes. Since the main air bleed passage 43 and the slow air bleed passage 45 open to the respective passage holes 46, the passage holes 46 function as a common path.

The valve body 47 is located in the passage hole 46. The passage hole 46 is formed in the vaporizer main body 12, and the valve body 47 is accommodated in the vaporizer main body 12. The valve body 47 is slidably brought into surface contact with the slide surface 46 b of the passage hole 46. The slide surface 46b extends in a direction in which gravity acts in parallel to the central axis 46a. The valve body 47 moves in the passage hole 46 in the axial direction. The first passage 43b of the main air bleed passage 43 extends in the intake passage direction (here, the horizontal direction) and opens at the slide surface 46b of the passage hole 46, and the passage hole 46 and the first passage 43b form a crank. . The opening 43 a of the first passage 43 b is formed by a drill hole that extends in the intake passage direction (here, the horizontal direction) and crosses the passage hole 46. The tip of the drill hole is connected to the first passage 43b, the tip of the first passage 43b is connected to the second passage 43c, and the second passage 43c is connected to the

main nozzle portions

37 and 39. In this way, the passage hole 46 is connected to the

main nozzle portions

37 and 39 via the

first connection passages

43 b and 43 c of the main air bleed passage 43, and air is mixed with the fuel measured by the main jet 37, and then from the main nozzle 39 to the intake passage 15. A mixture is released.

The third passage 45b of the slow air bleed passage 45 extends in the intake passage direction (here, the horizontal direction) and opens at the slide surface 46b like the main air bleed passage 43, and the crank is formed by the passage hole 46 and the third passage 45b. Forming. The opening 43a of the main air bleed passage 43 is disposed below the opening 45a of the slow air bleed passage 45 in the direction in which gravity acts. The main air bleed passage 43 and the slow air bleed passage 45 open at a position on the second reference line 46c extending in parallel to the reference line 46a. The opening 45 a of the third passage 45 b is formed by a drill hole that extends in the intake passage direction (here, the horizontal direction) and crosses the passage hole 46. The tip of the drill hole is connected to the third passage 45b, the tip of the third passage 45b is connected to the fourth passage 45c (see FIG. 3), and the fourth passage 45c is connected to the slow nozzle portions 38 and 41. In this way, the passage hole 46 is connected to the slow nozzle portions 38 and 41 through the

second connection passages

45b and 45c of the slow air bleed passage 45, and the air is mixed with the fuel measured by the slow jet 38. The air-fuel mixture is released.

An air introduction path 48 opens in the passage hole 46. One end of the air introduction path 48 is connected to the outside air space, that is, the intake path 15. One end of the air introduction path 48 is disposed on the upstream side of the throttle valve 19. The other end of the air introduction path 48 opens into the passage hole 46. The opening 48a of the air introduction path 48 is disposed at a position lower than the opening 43a of the main air bleed passage 43 (that is, below the opening 43a in the direction in which gravity acts). Air is introduced from the intake passage 15 into the passage hole 46 through the air introduction passage 48.

The valve body 47 is connected to an electric motor 51 as an electric drive member having a shaft (drive shaft 49). The reference line 46 a is coaxial with the drive shaft 49. A screw groove is formed in the drive shaft 49 of the electric motor 51. The thread groove meshes with the thread groove of the female thread member 52 fixed to the valve body 47. The rotational movement of the drive shaft 49 is converted into the axial movement of the female screw member 52 by the action of the thread groove. Thus, the axial movement of the valve body 47 is controlled according to the rotation control of the electric motor 51. In addition, a drive source such as an electromagnetic valve may be used instead of the electric motor 51 for driving the valve body. It is possible to control the rotation of the electric drive member (here, the electric motor 51) by feeding back the information of the O2 sensor installed on the upstream side of the internal combustion engine.

Between the carburetor main body 12 and the valve body 47 that define the passage hole 46, a rattling prevention mechanism M that prevents rattling of the valve body 47 within the passage hole 46 is established. The rattling prevention mechanism M includes a valve body side engagement 53 provided in the valve body 47 and a passage hole side engagement 54 provided in the vaporizer body 12 by the passage hole 46. The valve body side engagement 53 is formed by a key groove provided integrally with the valve body 47 and extending linearly in the sliding direction of the valve body 47. The passage hole side engagement 54 is configured by a guide that is fixed to the carburetor body 12 by the passage hole 46 and that engages with the key groove to guide the movement of the valve body 47. The guide should just be comprised by protrusion. The passage hole side engagement 54 is provided at a position closer to the opening 45 a of the slow air bleed passage 45 than the opening 43 a of the main air bleed passage 43. The valve body side engagement 53 and the passage hole side engagement 54 cooperate to form the valve body 47 with respect to the slide surface 46b in a rotation direction that is orthogonal to the slide operation direction and that is centered on the slide operation direction. Suppresses movement.

Here, the guide is received in the receiving hole 55 that is formed in the carburetor body 12 from the outer surface of the carburetor body 12 toward the passage hole 46 and opens in the passage hole 46. The receiving hole 55 has a circular cross section. The slow air bleed passage 45 has a key (expansion portion) having a circular cross section coaxially with the receiving hole 55.

As shown in FIG. 5, the valve body 47 includes a first valve body (first partition) 47 a that overlaps the opening (first opening) 45 a of the slow air bleed passage 45 according to the sliding operation, and a sliding operation. Thus, a second valve body (second partition) 47b that overlaps the opening (second opening) 43a of the main air bleed passage 43 is partitioned. A window hole 56 is formed in the valve body 47 when the first partition 47a is partitioned. A notch is formed in the outer edge 57 of the valve body 47 when the second partition 47b is partitioned. The opening area of the main air bleed passage 43 and the opening area of the slow air bleed passage 45 are changed according to the sliding operation of the valve body 47. The electric motor 51 and the drive shaft 49 function as a driving force transmission mechanism that drives the first valve body 47a. The driving force transmission mechanism employs a screw mechanism as described above. The power transmission mechanism, the opening 45a of the slow air bleed passage 45, and the opening 43a of the main air bleed passage 43 are arranged in one direction (here, the vertical direction). Since the second valve body 47b is integrated with the first valve body 47a, the second valve body 47b is interlocked with the first valve body 47a. The first valve body 47 a changes the opening area of the slow air bleed passage 45 at the passage hole 46, and the second valve body 47 b changes the opening area of the main air bleed passage 43 at the passage hole 46.

The passage hole 46 is provided upstream of the center line 17 b of the valve cylinder 14 in the intake passage direction and on the side surface side of the intake passage 15. The first passage 43 b of the main air bleed passage 43 and the third passage 45 b of the slow air bleed passage 45 extend along the intake passage 15. The air introduction path 48 extends toward the intake path 15 (here, in the horizontal direction toward the intake path 15) and forms a crank with respect to the passage hole 46.

The main air bleed passage 43 is particularly used when the engine negative pressure is low (high load), and the slow air bleed passage 45 is particularly used when the engine negative pressure is strong (low load). A first valve body 47 a for the slow air bleed passage 45 and a second valve body 47 b for the main air bleed passage 43 can be disposed in the passage hole 46. Therefore, the structure of the valve body 47 can be simplified. In addition, both the main air bleed passage 43 and the slow air bleed passage 45 can be opened to reduce the size by bringing both openings close to each other, and when shifting from a low load to a high load (acceleration), In the opposite case (during deceleration), the responsiveness can be improved (for example, when the opening area of the main air bleed passage 43 is rapidly opened during acceleration, it can be controlled from a state where it is opened to some extent in advance). .

In the vaporizer 11, since the first valve body 47a and the second valve body 47b are integrated, the first valve body 47a and the second valve body 47b can be formed as one member. Therefore, an increase in the number of parts is avoided. The burden of assembly work is reduced. Moreover, the valve body 47 can be formed compactly.

When supplying the air bleed, the first partition 56 a (first valve body 47 a) of the valve body 47 is displaced with respect to the first opening 45 a of the slow air bleed passage 45 to change the opening area of the slow air bleed passage 45. Similarly, the second partition 57 a (second valve body 47 b) of the valve body 47 is displaced with respect to the second opening 43 a of the main air bleed passage 43 to change the opening area of the main air bleed passage 43. The opening of the main air bleed passage 43 and the opening of the slow air bleed passage 45 are finely controlled in accordance with the sliding operation of the valve body 47. Further, since the opening area of the slide surface 46b is changed, the valve body 47 has a simple structure, and the valve body 47 can be made compact.

As described above, when the valve body 47 is driven, the rotation operation of the electric motor 51 is converted into a linear operation of the valve body 47. A screw mechanism is used as the driving power transmission mechanism for converting the driving force. The electric motor 51, the drive shaft 49, the opening 45a of the slow air bleed passage 45 and the opening 43a of the main air bleed passage 43 are provided side by side in one direction. A screw mechanism extending in one direction can be easily provided along the one direction. Since the direction other than one direction is compact (downsized), the passage hole 46 is installed in the carburetor 11 so that the carburetor 11 is compact (arranged in the valve cylinder 14 or along the outer shape of the intake passage 15). can do.

The first partition 56a (first valve body 47a) or the second partition 57a (second valve body 47b) is formed on the outer edge of the valve body 47. The valve body 47 can be made compact in one direction. Moreover, since the compact valve body 47 is installed in the vaporizer 11, the vaporizer 11 can be made compact.

The carburetor main body 12 has a passage hole 46 as an

air bleed passage

43, 45 on one side where the passage hole 46 is arranged on the basis of a plane VP including the center line 17a of the intake passage 15 and the center line 17b of the valve cylinder 14. The first passage 43b, the second passage 43c, the third passage 45b, and the fourth passage 45c are provided as connection passages extending toward the

nozzle portions

37, 39, 38, and 41 that face the intake passage 15 continuously. By arranging the passage hole 46, the main air bleed passage 43 and the slow air bleed passage 45 in a concentrated manner on one side of the carburetor body 12, the

air bleed passages

43 and 45 are formed relatively easily by molding or processing. The vaporizer 11 can be configured compactly.

The carburetor main body 12 is provided with an air introduction passage 48 that opens from the passage hole 46 toward the intake passage 15 as an air bleed passage on one side where the passage hole 46 is disposed with respect to the plane VP. The air introduction passage 48, the passage hole 46, and the connection passage (air bleed passages 43, 45) are concentrated on one side of the carburetor body 12, and the

air bleed passages

43, 45 are relatively easy to mold or process. The vaporizer 11 can be configured compactly.

The carburetor body 12 includes

first connection passages

43b and 43c that extend toward the

main nozzle portions

37 and 39 as the main air bleed passage 43, and a first connection passage that extends toward the main nozzle portions 38 and 41 as the slow air bleed passage 45. Two

connection paths

45b and 45c are formed. The first and second connection paths are concentrated on one side of the carburetor body 12, and the main air bleed passage 43 and the slow air bleed passage 45 can be formed relatively easily by molding or processing. The vaporizer 11 can be configured compactly.

Since a common passage for the main air bleed passage 43 and the slow air bleed passage 45 is formed in the passage hole 46, the valve bodies of the main air bleed and the slow air bleed can be integrated, and the carburetor 11 has a compact configuration. Can be done. In addition, since the common passage for the main air bleed passage 43 and the slow air bleed passage 45 is formed in the passage hole 46, the air introduction passage 48 can be shared as the main air bleed passage 43 and the slow air bleed passage 45. The vaporizer 11 can be configured compactly.

The valve body 47 includes a first valve body 47a that changes the opening area of the slow air bleed passage 45, and a second valve body 47b that is integrated with the first valve body 47a and changes the opening area of the main air bleed passage 43. Therefore, the valve body 47 is integrated by the slow air bleed passage 45 and the main air bleed passage 43, and in addition, the main air bleed passage 43 and the slow air bleed passage 45 open on the same slide surface 46b. The shape of the hole 46 can be simplified, and the

air bleed passages

43 and 45 can be easily formed. As a result, the vaporizer 11 can be made compact. Further, since the main air bleed passage 43 and the slow air bleed passage 45 are opened on the same slide surface 46b, negative pressure is generated in the direction of the valve body 47 toward the slide surface 46b, and the valve body 47 in the passage hole 46 is formed. It is possible to suppress rattling as much as possible.

The passage hole 46 is provided upstream of the center line 17 b of the valve cylinder 15 in the intake passage direction and on the side surface of the intake passage 15. The main air bleed passage 43 and the slow air bleed passage 45 extend along the intake passage 15. In addition, since the air introduction path 48 extends toward the intake path 15, the main air bleed passage 43, the slow air bleed passage 45, and the air introduction passage 48 can be easily provided, and the carburetor 11 has a compact configuration. can do.

A main air bleed passage 43, a slow air bleed passage 45, and a passage hole 46 are arranged on one side of the carburetor body 12, and the choke valve 28 is installed on the other side of the one side from the choke valve 28 to the operation lever 60. Therefore, the vaporizer 11 can be configured in a compact manner.

As described above, the valve body 47 realizes a sliding operation along the sliding surface 46b of the passage hole 46. The valve body 47 is displaced with respect to the

openings

43a and 45a of the

air bleed passages

43 and 45 to change the opening areas of the

air bleed passages

43 and 45. The opening degree of the

air bleed passages

43 and 45 is finely controlled according to the sliding operation of the valve body 47. At this time, since the slide surface 46b extends in the direction in which gravity acts, foreign matters such as dust and fuel in the airflow fall below the valve body 47 and accumulate at the lower end of the passage hole 46. Biting into the contact surface is prevented. Thus, when the opening degree of the air bleed passage is controlled, dust and fuel can be prevented from being mixed and accumulated as much as possible. In addition, since the

air bleed passages

43 and 45 are open to the slide surface 46 b and the opening area of the slide surface 46 b is changed by the valve body 47, the opening area of the slide surface 46 b is changed by the valve body 47. Entry of foreign matter and entry of foreign matter to the slide surface 46b that affects the opening area are suppressed. In this way, distribution control can be maintained with higher accuracy.

The other end of the air introduction path 48 opens to the passage hole 46 below the

openings

43a and 43a of the

air bleed passages

43 and 45 in the direction in which gravity acts. When outside air is introduced into the passage hole 46 from the air introduction path 48, foreign matter mixed in the outside air enters the passage hole 46 below in the direction in which gravity acts than the

openings

43 a and 45 a of the

air bleed passages

43 and 45. . In this way, entry of foreign matter into the

air bleed passages

43 and 45 can be further suppressed.

In the carburetor 11, the main air bleed passage 43 opens downward in the direction in which gravity acts as compared to the slow air bleed passage 45. In the passage hole 46, the foreign matter accumulates downward in the direction of gravity by its own weight. Compared with the slow air bleed passage 45, foreign matters are likely to enter the main air bleed passage 43, so that foreign matters enter the slow air bleed passage 45 to the maximum extent. By avoiding the mixing of foreign matters, the slow air bleed passage 45 can maintain the flow control with high accuracy. In the carburetor 11, the control of the slow air bleed passage 45 requires higher accuracy than the control of the main air bleed passage 43.

In the passage hole 46, an air introduction path 48 is opened upstream, a main air bleed path 43 is opened downstream thereof, and a slow air bleed path 45 is opened downstream thereof. Since foreign matter tends to enter the main air bleed passage 43 due to the flow of intake air, entry of foreign matter into the slow air bleed passage 45 is suppressed to the maximum. By avoiding the mixing of foreign matters, the slow air bleed passage 45 can maintain the flow control with high accuracy.

The main air bleed passage 43 and the slow air bleed passage 45 open at a position on a second reference line extending in parallel to a reference line 46a coaxial with the axis. The outside air introduced from the air introduction passage 48 approaches the main air bleed passage 43 first. Dust and fuel enter the main air bleed passage 43 more easily than the slow air bleed passage 45. In this way, entry of foreign matter into the slow air bleed passage 45 is suppressed to the maximum.

The passage hole 46 is provided on the side surface side of the intake passage 15, and a reference line 46 a coaxial with the shaft 49 and a second reference line 46 c parallel to the reference line 46 a are in the intake passage direction (the direction in which the intake passage 15 extends). The valve cylinder 14 extends in the direction extending in the direction orthogonal to the valve cylinder direction (the direction in which the valve cylinder 14 extends), and the air introduction path 48 extends to the intake path 15 in the intake path direction view. Here, a crank is formed with respect to the passage hole 46 extending in the horizontal direction (here, in a vertical position). Thus, since the air introduction path 48 forms a crank with respect to the passage hole 46 (which is a common path here), foreign matter in the outside air collides with the wall surface of the passage hole 46 by inertia force when entering the passage hole 46. . After the collision, the foreign object falls downward. In this way, entry of foreign matter into the main air bleed passage 43 and the slow air bleed passage 45 can be further suppressed. A reference line 46a that is coaxial with the shaft 49 and a second reference line 46c that is parallel to the reference line 46a are provided in the side surface of the intake passage 15 and in the direction perpendicular to the intake passage direction and in the valve cylinder direction. Since the valve cylinder 14 is provided in the extending direction (here, in the direction along the valve cylinder 14) when viewed in the orthogonal direction, the

air bleed passages

43 and 45 are formed in the carburetor main body 12 to make the carburetor 11 compact. Can be.

Outside air is introduced into the passage hole 46 (here, on the common path). The outside air flows from the common path into the main air bleed passage 43 and the slow air bleed passage 45 in accordance with the sliding operation of the first valve body 47a and the second valve body 47b. The first valve body 47 a is displaced with respect to the opening 45 a of the slow air bleed passage 45 and changes the opening area of the slow air bleed passage 45. Similarly, the second valve body 47 b is displaced with respect to the opening 43 a of the main air bleed passage 43 to change the opening area of the main air bleed passage 43. The main air bleed passage 43 and the slow air bleed passage 45 are precisely and finely controlled because the first valve body 47a and the second valve body 47b open at a position on the second reference line 46c according to the sliding operation. Here, in the sliding operation, the valve body side engagement 53 and the passage hole side engagement 54 can regulate both rattling of the first valve body 47a and the second valve body 47b. Further, since the main air bleed passage 43 and the slow air bleed passage 45 are opened in the slide surface 46b, negative pressure is generated in the direction toward the slide surface 46b, and the valve body 47 in the passage hole 46 is Tack can be suppressed as much as possible. At this time, the electric motor 51, the main air bleed passage 43, and the slow air bleed passage 45 can be arranged like a laminated structure on a virtual plane orthogonal to the reference line 46a coaxial with the shaft 49. The air bleed passage 43 and the slow air bleed passage 45 can be concentrated around the passage hole 46 (here, around the common passage).

The passage hole side engagement 54 meshes with the valve element side engagement 53 at a position closer to the opening 45 a of the slow air bleed passage 45 than the opening 43 a of the main air bleed passage 43, so that the slow air bleed is more than the main air bleed passage 43. Shaking of the valve body 47 in the passage 45 is suppressed. Thus, higher accuracy is realized by controlling the flow rate of the slow air bleed passage 45 than by the main air bleed passage 43. In the carburetor 11, the control of the slow air bleed passage 45 is required to have higher accuracy than the control of the main air bleed passage 43.

The valve body side engagement 53 is a key groove provided integrally with the valve body 47 and extending linearly in the sliding direction. The passage hole side engagement 54 is fixed to the passage hole 46 and meshes with the key groove. This is a protrusion for guiding the movement of the valve body 47. The engagement for restricting the movement of the first valve body 47a and the second valve body 47b can be easily formed. Further, by forming a key groove integrally with the valve body 47, no new parts are required.

The slow air bleed passage 45 has a key that is formed in the passage hole 46 to receive the passage hole side engagement 54 and has a circular cross section in the circular reception hole 55. The slow air bleed passage 45 and the receiving hole 55 are formed coaxially with the passage hole 46 interposed therebetween. Therefore, the slow air bleed passage 45 and the receiving hole 55 can be processed into the carburetor body 12 by a common drilling process.

The carburetor main body 12 defines an intake passage 15 in the body 13, and defines a slide space 16 branched from the intake passage 15 by a valve cylinder 14 integrated with the body 13. A throttle valve 19 that changes the opening area of the passage 15 is accommodated in the valve cylinder 14. A passage hole 46 is provided in the vaporizer body 12. Since the electric motor 51, the main air bleed passage 43, and the slow air bleed passage 45 can be concentrated around the passage hole (here, around the common passage), the carburetor 11 can be configured compactly.

As shown in FIG. 6, in the vaporizer 11 a according to the second embodiment of the present invention, the gravity of the opening 43 a of the main air bleed passage 43 acts more than the opening 45 a of the slow air bleed passage 45 as described above. Arranged downward in the direction. On the other hand, the opening 48a of the air introduction passage 48B is disposed at a position higher than the opening 45a of the slow air bleed passage 45 (that is, above the opening 45a in the direction in which gravity acts). Other configurations are the same as those of the first embodiment.

The main air bleed passage 43 opens downward in the direction in which gravity acts as compared to the slow air bleed passage 45. In the passage hole 46, foreign matter accumulates downward in the direction of gravity due to its own weight, so that the flow control in the slow air bleed passage 45 can be maintained with high accuracy.

The air introduction path 48 extends to the intake path 15 when viewed in the intake path direction, and forms a crank with respect to the passage hole 46 (here, extending in the horizontal direction and having a vertical posture here). Thus, since the air introduction path 48 forms a crank with respect to the passage hole 46 (here, a common path), foreign matter in the outside air collides with the wall surface of the passage hole 46 by inertia force when entering the passage hole 46. After the collision, the foreign object falls downward. In this way, entry of foreign matter into the main air bleed passage 43 and the slow air bleed passage 45 can be further suppressed.

As shown in FIG. 6, in the carburetor 11b according to the third embodiment of the present invention, the gravity of the opening 43a of the main air bleed passage 43 acts more than the opening 45a of the slow air bleed passage 45, as described above. Arranged downward in the direction. On the other hand, the opening 48b of the air introduction passage 48 is located at a position lower than the opening 45a of the slow air bleed passage 45 and higher than the opening 43a of the main air bleed passage 43 (that is, opening in the direction in which gravity acts). 45a and below the opening 43a). Other configurations are the same as those of the first embodiment.

The air introduction path 48 extends to the intake path 15 when viewed in the direction of the intake passage, and forms a crank with respect to the passage hole 46 (extending in the horizontal direction here and in a vertical position here). Thus, since the air introduction path 48 forms a crank with respect to the passage hole 46 (here, a common path), foreign matter in the outside air collides with the wall surface of the passage hole 46 by inertia force when entering the passage hole 46. After the collision, the foreign object falls downward. In this way, entry of foreign matter into the main air bleed passage 43 and the slow air bleed passage 45 can be further suppressed.

As described above, the carburetor 11 in the embodiment of the present invention is mounted on a motorcycle having a limited mounting space, the idle opening of the throttle valve 19 is set by the idle screw 70 (see FIG. 2), and the third path 45b. is disposed to the intermediate passage 45b ₁ which is formed by bending the, closes the distal end of the intermediate passage 45b _1, the air screw 71 for throttling the opening area of the slow air bleed passage 45, basic slow air bleed passage 45 The opening (the opening serving as a reference for control by the valve body 47) is set (see FIG. 3), and the throttle cable 21 of the throttle valve 19 and the operation lever of the choke valve 28 are operated by the operator. The ECU that has received the O2 sensor signal instructs the electric drive member to control the movement of the valve body 47. In this way, fine control is realized.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It is possible to perform a various design change, without deviating from the summary.

Claims

Common path (46),
A main air bleed passage (43) and a slow air bleed passage (45) individually connected to the common passage (46);
A first valve body (47a) for changing an opening area of the main air bleed passage (43) in the common path (46);
A driving force transmission mechanism (49, 51) for driving the first valve body (47a);
A second valve body (47b) that changes the opening area of the slow air bleed passage (45) in the common path (46) while interlocking with the first valve body (47a);
A vaporizer characterized by comprising.
The carburetor according to claim 1, wherein the first valve body (47a) and the second valve body (47b) are integrated.
The vaporizer according to claim 2, wherein
A slide surface (46b) facing the space of the common path (46) is defined, opened at the slide surface (46b), and connected to either the main air bleed passage (43) or the slow air bleed passage (45). And a passage having a second opening (43a) that opens at the slide surface (46b) and is connected to the other of the main air bleed passage (43) and the slow air bleed passage (45). With holes (46),
The first and second valve bodies (47a, 47b) are slidably brought into surface contact with the slide surface (46b) of the passage hole (46) and overlap the first opening (45a) according to a slide operation. A carburetor characterized by partitioning the first partition (56a) and the second partition (57a) overlapping the second opening (43a) in accordance with a sliding operation.
The vaporizer according to claim 3, wherein a screw mechanism is used for the driving force transmission mechanism (49, 51), the driving force transmission mechanism (49, 51), the first opening (45a) and the second. A vaporizer characterized in that the openings (43a) are arranged in one direction.
The carburetor according to claim 3 or 4, wherein the first or second partition (56a, 57a) is formed on an outer edge (57) of the first and second valve bodies (47). Vaporizer.