INTAKE CONTROL DEVICE

Abstract

An intake control device 1 includes: a body 3 including an intake passage 2; and a valve body 4 located in the intake passage 2. The intake passage 2 includes a direction continuation segment 13 in which a first major axis direction d1 and a second major axis direction d2 are approximately parallel to each other continuously from a downstream opening 6 of the body 3. The body 3 includes a seal plane 14 formed along a plane that intersects with part of the direction continuation segment 13. The valve body 4 includes a valve plane 15 formed by a plane that abuts the seal plane 14, and is configured to slide relative to the seal plane 14 via the valve plane 15 to adjust an opening degree of the intake passage 2.

Claims

1. An intake control device comprising: a body including an intake passage that is at least part of an intake pipe leading to a combustion chamber of an internal combustion engine; and a valve body located in the intake passage, wherein the body includes an upstream opening and a downstream opening of the intake passage, the intake passage includes a direction continuation segment in which a first long axis direction and a second long axis direction are approximately parallel to each other continuously from the downstream opening, the first long axis direction being a direction orthogonal to a first parallel equal-interval dividing line group when a sum total of a product of an area of each of an unlimited number of fine openings and a shortest distance of the fine opening from a downstream center point that is an area center of the downstream opening is maximum, the unlimited number of fine openings being obtained by dividing, by the first parallel equal-interval dividing line group, a shape of the downstream opening as seen from a direction parallel to a passage center line that is a straight line connecting an upstream center point that is an area center of the upstream opening and the downstream center point, the second long axis direction being a direction orthogonal to a second parallel equal-interval dividing line group when a sum total of a product of an area of each of an unlimited number of fine passage cut shapes and a shortest distance of the fine passage cut shape from an area center of a passage cut shape that is a cross-sectional shape of the intake passage cut along any surface orthogonal to the passage center line is maximum, the unlimited number of fine passage cut shapes being obtained by dividing the passage cut shape by the second parallel equal-interval dividing line group, wherein the body includes a seal plane formed along at least part of a plane that intersects with at least part of the direction continuation segment, and wherein the valve body includes a valve plane formed by a plane that abuts the seal plane, and is configured to slide relative to the seal plane via the valve plane to adjust an opening degree of the intake passage.

2. The intake control device according to claim 1, comprising: a slide block configured to be translatably guided by the body and moved along the seal plane while holding the valve body to enable the valve body to slide relative to the seal plane; and a friction reduction means provided between the body and the slide block and configured to reduce friction when the slide block is guided by the body, wherein the slide block includes a storage hole for storing at least part of the valve body on an upstream side to allow mutual movement of the slide block and the valve body, wherein an airtight member configured to keep the storage hole airtight is provided between the slide block and the valve body, and wherein the valve body includes a communicating hole through which the upstream side and a downstream side of the valve body communicate with each other and that causes inside of the storage hole to communicate with the downstream side of the valve body of the intake passage.

3. The intake control device according to claim 1, wherein the valve body is configured to slide relative to the seal plane to increase the opening degree of the intake passage in the case of moving from one side to an other side of the intake passage, and wherein the seal plane is inclined toward an upstream side of the intake passage with respect to the passage center line from the one side to the other side of the intake passage.

4. The intake control device according to claim 3, wherein an injection port of a fuel injection valve configured to inject fuel into the intake pipe is located on the one side of the intake passage and downstream from the valve body in the intake passage.

5. The intake control device according to claim 4, wherein the valve body includes a surface lacking portion depressed and open to the one side at a valve end that is an end of the valve plane on the one side, and wherein the surface lacking portion is configured to be exposed into the intake passage before the valve end, during a time from when the valve body is in a fully closed state in which the opening degree of the intake passage is minimum to when the valve body is in a fully open state in which the opening degree of the intake passage is maximum

6. The intake control device according to claim 1, wherein the valve body is configured to slide relative to the seal plane to increase the opening degree of the intake passage in the case of moving from one side to another side of the intake passage, wherein the intake control device comprises a first transmission mechanism configured to slide the valve body relative to the seal plane, and wherein the first transmission mechanism is located on the other side of the intake passage and on the upstream side of the intake passage from a first reference plane including the seal plane.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0049] FIG. 1 is a perspective diagram illustrating an intake control device according to an embodiment of the present invention.

[0050] FIG. 2 is a front diagram of the intake control device in FIG. 1 as seen from the downstream side.

[0051] FIG. 3 is a cross-sectional diagram taken along line in FIG. 2.

[0052] FIG. 4 is an enlarged diagram illustrating a part in FIG. 2.

[0053] FIG. 5A is a diagram illustrating a first major axis direction in a shape of a downstream opening in the intake control device in FIG. 1.

[0054] FIG. 5B is a diagram illustrating a second major axis direction in a passage cut shape in the intake control device in FIG. 1.

[0055] FIG. 6 is a perspective diagram illustrating a valve body held by a slide block in the intake control device in FIG. 1.

[0056] FIG. 7 is a perspective diagram illustrating a second transmission mechanism in the intake control device in FIG. 1.

[0057] FIG. 8 is an enlarged diagram illustrating a part of the intake control device in FIG. 1 as seen from the upstream side.

[0058] FIG. 9 is a diagram illustrating the positional relationship between a frame of a motorcycle and the intake control device in FIG. 1 in the case where the intake control device is mounted in the motorcycle.

[0059] FIG. 10 is a diagram illustrating the positional relationship between an engine of a motorcycle and the intake control device in FIG. 1 in the case where the intake control device is mounted in the motorcycle.

[0060] FIG. 11A is a diagram illustrating another example of the shape of the downstream opening in the intake control device in FIG. 1.

[0061] FIG. 11B is a diagram illustrating yet another example of the shape of the downstream opening in the intake control device in FIG. 1.

[0062] FIG. 11C is a diagram illustrating yet another example of the shape of the downstream opening in the intake control device in FIG. 1.

DESCRIPTION OF EMBODIMENTS

[0063] An embodiment of the present invention will be described below, with reference to the drawings. As illustrated in FIG. 1 and FIG. 2, an intake control device 1 according to an embodiment of the present invention includes two bodies 3 each of which includes two intake passages 2 that are each at least part of an intake pipe leading to a combustion chamber of an internal combustion engine, and a valve body 4 located in each intake passage 2.

[0064] Thus, the intake control device 1 is suitable for being mounted in a straight-four engine as an internal combustion engine. Each body 3 includes an upstream opening 5 and a downstream opening 6 of each intake passage 2. A funnel F is provided on the upstream side of the intake passage 2.

[0065] Herein, as illustrated in FIG. 3 and FIG. 4, a passage center line 7 is a straight line connecting an upstream center point P1 which is an area center of the upstream opening 5 and a downstream center point P2 which is an area center of the downstream opening 6.

[0066] As illustrated in FIG. 5A, a first major axis direction d1 is a direction orthogonal to a first parallel equal-interval dividing line group 8 when the sum total of the product of the area of each of an unlimited number of fine openings 9 obtained by dividing, by the first parallel equal-interval dividing line group 8, the shape of the downstream opening 6 as seen from a direction parallel to the passage center line 7 and the shortest distance S1 of the fine opening 9 from the downstream center point P2 is maximum.

[0067] As illustrated in FIG. 5B, a second major axis direction d2 is a direction orthogonal to a second parallel equal-interval dividing line group 11 when the sum total of the product of the area of each of an unlimited number of fine passage cut shapes 12 obtained by dividing, by the second parallel equal-interval dividing line group 11, a passage cut shape 10 which is the cross-sectional shape of the intake passage 2 cut along any surface orthogonal to the passage center line 7 and the shortest distance S2 of the fine passage cut shape 12 from the area center P3 of the passage cut shape 10 is maximum

[0068] The intake passage 2 includes a direction continuation segment 13 (see FIG. 3) in which the first major axis direction d1 and the second major axis direction d2 are approximately parallel to each other continuously from the downstream opening 6. In this embodiment, the entire intake passage 2 is the direction continuation segment 13.

[0069] As illustrated in FIG. 3, the body 3 includes a seal plane 14 formed along at least part of a plane that intersects with at least part of the direction continuation segment 13. The seal plane 14 is formed at a wall portion of the intake passage 2 by a plane extending at an angle with the extending direction of the intake passage 2, and is inclined toward the upstream side of the intake passage 2 with respect to the passage center line 7 from one side d3 to the other side d4 of the intake passage 2.

[0070] The valve body 4 includes a valve plane 15 formed by a plane that abuts the seal plane 14, and slides relative to the seal plane 14 via the valve plane 15 to adjust the opening degree of the intake passage 2 (i.e. the degree of opening of the intake passage 2 as a result of the movement of the valve body 4).

[0071] In detail, the opening degree of the intake passage 2 is adjusted by the valve plane 15 blocking, by an area corresponding to each position of the valve body 4, a cross-section of the intake passage 2 cut along a surface including the seal plane 14. The direction in which the valve body 4 slides along the seal plane 14 is a direction (minor axis direction) perpendicular to the first major axis direction d1 or the second major axis direction d2.

[0072] The body 3 is provided with a slide block 16 that is translatably guided by the body 3 and is moved along the seal plane 14 while holding the valve body 4 to enable the valve body 4 to slide relative to the seal plane 14. A friction reduction means that reduces friction when the slide block 16 is guided by the body 3 is provided between the body 3 and the slide block 16.

[0073] As illustrated in FIG. 6, rollers 17 that are rotatably supported by the slide block 16 and roll on a guide plane provided in the body 3 are used as the friction reduction means in this embodiment.

[0074] As illustrated in FIG. 3, the slide block 16 includes a storage hole 18 for storing at least part of the valve body 4 on the upstream side to allow mutual movement of the slide block 16 and the valve body 4. An airtight member 19 that keeps the storage hole 18 airtight is provided between the slide block 16 and the valve body 4. For example, a lip seal may be used as the airtight member 19.

[0075] The slide block 16 and the valve body 4 are fitted together so as to be mutually movable in the depth direction of the storage hole 18. The valve body 4 includes a communicating hole 21 through which the upstream side and the downstream side of the valve body 4 communicate with each other and that causes a received pressure reduction space 20 inside the storage hole 18 to communicate with the intake passage 2 downstream from the valve body 4. The communicating hole 21 maintains the pressure inside the received pressure reduction space 20 to be equal to low pressure on the downstream side of the valve body 4 in the intake passage 2. Thus, the received pressure reduction space 20 for reducing the force of biasing the valve body 4 toward the seal plane 14 is formed between the slide block 16 and the valve body 4.

[0076] As illustrated in FIG. 6, the valve body 4 includes, at a valve end 22 on the one side d3 (see FIG. 3) of the valve plane 15, a surface lacking portion 23 depressed and open to the one side d3 along the valve plane 15. In detail, the surface lacking portion 23 extends from the tip of the valve end 22 toward the other side d4 (see FIG. 3) along the valve plane 15, and has a curvature greater than the curvature of the inner surface of the intake passage 2 on the other side d4.

[0077] The surface lacking portion 23 is configured to be exposed into the intake passage before the valve end 22, during the time from when the valve body 4 is in a fully closed state in which the opening degree of the intake passage 2 is minimum to when the valve body 4 is in a fully open state in which the opening degree is maximum

[0078] In the intake control device 1 having these components, the valve body 4 is configured to increase the opening degree of the intake passage 2 in the case of sliding relative to the seal plane 14 to move from the one side d3 toward the other side d4 of the intake passage 2.

[0079] As illustrated in FIG. 3, the drive force for sliding the valve body 4 relative to the seal plane 14 is transmitted from a first transmission mechanism 24. The first transmission mechanism 24 is located on the other side d4 of the intake passage 2 and on the upstream side of the intake passage 2 from a first reference plane 25 including the seal plane 14.

[0080] The first transmission mechanism 24 includes a drive transmission shaft 26 that is located on the other side d4 of the intake passage 2 and rotates, and an arm-shaped valve body drive portion 27 whose base end is fixed to the drive transmission shaft 26 and whose tip end is linked to the slide block 16 rotatably and translatably.

[0081] The drive transmission shaft 26 is rotated by an electric motor 30 including a drive shaft 29 (see FIG. 7) approximately parallel to the rotation axis 28 of the drive transmission shaft 26. A valve body storage portion 31 for storing the valve body 4 and the like that slide to an open position is provided in the space in which the first transmission mechanism 24 is stored.

[0082] Thus, the valve body storage portion 31 functions as a space for allowing, when the valve body 4 opens, the tip end of the valve body drive portion 27 that swings as a result of the rotation of the drive transmission shaft 26, the slide block 16 linked to the tip end of the valve body drive portion 27, and the valve body 4 held by the slide block 16 to move in the sliding direction of the valve body 4 without hindrance.

[0083] As illustrated in FIG. 7, a second transmission mechanism 32 that includes a distance gear 32a and the like and transmits a drive force from the electric motor 30 to the drive transmission shaft 26 is provided between the electric motor 30 and the drive transmission shaft 26. The second transmission mechanism 32 is covered with a sensor cover 32b.

[0084] As illustrated in FIG. 3 and FIG. 4, the electric motor 30 is located on the one side d3 opposite to the drive transmission shaft 26 with the intake passage 2 therebetween as seen from a direction orthogonal to a second reference plane 33 that is parallel to the sliding direction of the valve body 4 and includes a sliding center line intersecting with the passage center line 7 and the passage center line 7.

[0085] A first reference line 35 that intersects with the rotation axis 28 of the drive transmission shaft 26 and the rotation axis 36 of the drive shaft 29 and the first reference plane 25 intersect with a line L including the passage center line 7 at respective acute corresponding angles and the corresponding angle β of the first reference line 35 is greater than the corresponding angle α of the first reference plane 25 as seen from a direction orthogonal to the second reference plane 33.

[0086] As illustrated in FIG. 8, at least part of the electric motor 30 is closer to the intake passage 2 than a third reference plane 37 is. The third reference plane 37 is a plane parallel to the passage center line 7, orthogonal to the rotation axis 28 of the drive transmission shaft 26, and in contact with the edge of the intake passage 2 on the side on which the second transmission mechanism 32 is located.

[0087] An opening degree sensor 38 that detects the rotation angle of the drive transmission shaft 26 is located at the end of the drive transmission shaft 26 on the side on which the second transmission mechanism 32 is located as seen from a direction parallel to the passage center line 7. A detection portion of the opening degree sensor 38 is provided on the back of the sensor cover 32b. In FIG. 7, the portion detected by the opening degree sensor 38 is fixed to the drive transmission shaft 26.

[0088] As illustrated in FIG. 3, an injection port 41 of a fuel injection valve 39 that injects fuel into the intake passage 2 is located on the one side d3 of the intake passage 2 and downstream from the valve body 4 in the intake passage 2. A main body of the fuel injection valve 39 is located on the one side d3 of the intake passage 2 and downstream from the electric motor 30. A first coupler 42 to which a first power supply terminal for supplying power to the fuel injection valve 39 is connected and a second coupler 43 to which a second power supply terminal for supplying power to the electric motor 30 is connected are provided on the one side d3 of the intake passage 2. A first opening 44 of the first coupler 42 for receiving the first power supply terminal and a second opening 45 of the second coupler 43 for receiving the second power supply terminal are both open to the one side d3.

[0089] As illustrated in FIG. 3 and FIG. 4, two joints 40 are provided on the other side d4 and on the downstream side of the intake passage 2 from the valve body 4. Each joint 40 is connected to a passage that is open to the inner wall of the intake passage 2 on the other side d4 and the downstream side. A conduit for introducing purged fuel from a canister into the intake passage 2 is connected to one joint 40. A conduit to a sensor for measuring the pressure in the intake pipe downstream from the valve body 4 is connected to the other joint 40.

[0090] When the intake control device 1 having this structure controls intake air, the electric motor 30 is driven and the position of the valve body 4 is adjusted to achieve the target opening degree of the intake passage 2.

[0091] Here, the drive force of the electric motor 30 is transmitted to the drive transmission shaft 26 of the first transmission mechanism 24 via the second transmission mechanism 32, and the valve body drive portion 27 swings with the rotation of the drive transmission shaft 26. The slide block 16 is thus moved along the first reference plane 25 from the one side d3 to the other side d4 of the intake passage 2 or from the other side d4 to the one side d3 of the intake passage 2.

[0092] During this, the rotation angle of the drive transmission shaft 26 is monitored by the opening degree sensor 38. The monitoring result is fed back to the drive amount of the electric motor 30, with reference to the target opening degree. The valve body 4 is thus positioned at the target opening degree.

[0093] During the movement of the valve body 4, between the seal plane 14 and the valve plane 15 is sealed. The load placed between the seal plane 14 and the valve plane 15 is reduced as a result of the communicating hole 21 maintaining the pressure inside the received pressure reduction space 20 to be equal to low pressure on the downstream side of the valve body 4 in the intake passage 2.

[0094] Due to the difference between the pressure inside the received pressure reduction space 20 and the high pressure upstream from the slide block 16, a force of biasing to the downstream side of the intake passage 2 is exerted on the slide block 16. Here, since the rollers 17 are provided between the body 3 and the slide block 16, the valve body 4 can be slid relative to the seal plane 14 very smoothly.

[0095] In the case where the intake passage 2 opens from the fully closed state with the movement of the valve body 4, the surface lacking portion 23 is exposed into the intake passage 2 before the valve end 22. Meanwhile, the seal plane 14 is inclined toward the upstream side of the intake passage 2. Therefore, in a low opening degree state in which the opening degree is low, intake air is rectified and concentrated at flow of fuel from the fuel injection valve 39, thus facilitating vaporization of fuel and uniformization of an air-fuel mixture.

[0096] The valve body 4 moves in a direction (minor axis direction) perpendicular to the first major axis direction d1 or the second major axis direction d2 which is the major axis direction of the elliptical cross-section of the intake passage 2, until the fully open state is reached. Hence, the valve body 4 can reach the fully open state with a relatively small amount of movement for the cross-sectional area of the intake passage 2. Likewise, the valve body 4 can return from the fully open state to the fully closed state with a relatively small amount of movement.

[0097] As described above, according to this embodiment, between the seal plane 14 and the valve plane 15 is sealed when the valve body 4 moves. Thus, even in the case where the cross-sectional shape of the intake passage 2 is a complex shape that is not circular, the opening degree of the intake passage 2 can be set exactly depending on the position of movement of the valve body 4 without requiring high accuracy for the gap between the intake passage 2 and the valve body 4. Therefore, even in the case where the cross-sectional shape of the intake passage 2 is complex and the opening degree of the intake passage 2 is low, the intake amount can be adjusted accurately.

[0098] Moreover, part of the valve body 4 is held in the storage hole 18 of the slide block 16, and the inside of the storage hole 18 is made equal to the pressure downstream from the valve body 4 to thus form the received pressure reduction space 20. This can reduce the load exerted between part of the valve plane 15 and the seal plane 14. Further, since the rollers 17 are provided between the body 3 and the slide block 16, the drive force needed to move the valve body 4 and the slide block 16 can be reduced, and wear of the valve body 4 and the like during the movement can be reduced.

[0099] Moreover, since the seal plane 14 is inclined with respect to the intake passage 2 as mentioned above, when the opening degree of the intake passage 2 is low, intake air gathers on the one side d3 of the intake passage 2 upstream from the valve body 4 and flows on the one side d3 of the valve body 4. The intake air can thus be rectified.

[0100] Moreover, the injection port 41 of the fuel injection valve 39 for injecting fuel into the intake pipe is located on the one side d3 of the intake passage 2 and downstream from the valve body 4 in the intake passage 2. Hence, when the opening degree of the intake passage 2 is low, strong flow of intake air collides with flow of fuel discharged from the injection port 41, with it being possible to vaporize fuel and uniformize an air-fuel mixture.

[0101] Moreover, in the case where the intake control device 1 is mounted in the engine 46 of a motorcycle in a downdraft manner, the foregoing arrangement of the opening degree sensor 38, the second transmission mechanism 32, and the like and the shape of the sensor cover 32b along these components can prevent the intake control device 1 from interfering with a frame 47 of the motorcycle, as illustrated in FIG. 9.

[0102] Moreover, the first transmission mechanism 24 is located on the other side d4 of the intake passage 2 and on the upstream side of the intake passage 2 from the first reference plane 25 including the seal plane 14, as illustrated in FIG. 3. Accordingly, in the case where the intake control device 1 is placed in a downdraft manner for the cylinder head 48 of the engine 46, the intake control device 1 can be located closer to the cylinder head 48 without the first transmission mechanism 24 interfering with the cylinder head 48, as illustrated in FIG. 10. In this way, the volume of the intake pipe downstream from the valve body 4 is reduced, as a result of which the response of the engine 46 can be enhanced.

[0103] Moreover, since the seal plane 14 is a plane that intersects with the direction continuation segment 13, the stroke amount of the valve body 4 from the fully closed state in which the opening degree of the intake passage 2 is minimum to the fully open state in which the opening degree is maximum can be decreased. Hence, the first transmission mechanism 24 and the valve body storage portion 31 can be reduced in size.

[0104] Moreover, as a result of the angle β of the first reference line 35 with the extending direction of the intake passage 2 (the direction of the passage center line 7) being as close to a right angle as possible, the distance from the electric motor 30 to the drive transmission shaft 26 can be shortened and the second transmission mechanism 32 can be reduced in size.

[0105] Moreover, the electric motor 30 is located on the upstream side of the intake passage 2 due to, for example, the foregoing positional relationship between the first reference plane 25 and the first reference line 35. Thus, the injection port 41 of the fuel injection valve 39 can be provided at such a position that is advantageous in vaporizing fuel and uniformizing an air-fuel mixture in a low opening degree state in which the opening degree of the intake passage 2 is low.

[0106] Moreover, as a result of the first opening 44 of the first coupler 42 and the second opening 45 of the second coupler 43 being both open to the one side d3, wiring to these parts can be advantageously routed.

[0107] Moreover, in the case where the intake passage 2 opens from the fully closed state, the surface lacking portion 23 is exposed into the intake passage 2 before the valve end 22. Therefore, intake air is concentrated at flow of fuel from the fuel injection valve 39, thus further facilitating vaporization of fuel and uniformization of an air-fuel mixture in a low opening degree state.

[0108] While the embodiment of the present invention has been described above, the present invention is not limited to such. For example, the shape of the downstream opening of the intake passage 2 may be the shape of any of downstream openings 6a to 6c illustrated in FIG. 11A to FIG. 11C respectively. In each example, the first major axis direction d1 is defined in the same way as in FIG. 5A. The internal combustion engine to which the present invention is applied is not limited to a straight-four engine, and may be an engine of any other form and any other number of cylinders.

DESCRIPTION OF REFERENCE NUMERALS

[0109] 1 intake control device

[0110] 2 intake passage

[0111] 3 body

[0112] 4 valve body

[0113] 5 upstream opening

[0114] 6, 6a to 6c downstream opening

[0115] 7 passage center line

[0116] 8 first parallel equal-interval dividing line group

[0117] 9 fine opening

[0118] 10 passage cut shape

[0119] 11 second parallel equal-interval dividing line group

[0120] 12 fine passage cut shape

[0121] 13 direction continuation segment

[0122] 14 seal plane

[0123] 15 valve plane

[0124] 16 slide block

[0125] 17 roller

[0126] 18 storage hole

[0127] 19 airtight member

[0128] 20 received pressure reduction space

[0129] 21 communicating hole

[0130] 22 valve end

[0131] 23 surface lacking portion

[0132] 24 first transmission mechanism

[0133] 25 first reference plane

[0134] 26 drive transmission shaft

[0135] 27 valve body drive portion

[0136] 28 rotation axis

[0137] 29 drive shaft

[0138] 30 electric motor

[0139] 31 valve body storage portion

[0140] 32 second transmission mechanism

[0141] 32a distance gear

[0142] 32b sensor cover

[0143] 33 second reference plane

[0144] 35 first reference line

[0145] 36 rotation axis

[0146] 37 third reference plane

[0147] 38 opening degree sensor

[0148] 39 fuel injection valve

[0149] 40 joint

[0150] 41 injection port

[0151] 42 first coupler

[0152] 43 second coupler

[0153] 44 first opening

[0154] 45 second opening

[0155] 46 engine

[0156] 47 frame

[0157] 48 cylinder head

[0158] d1 first major axis direction

[0159] d2 second major axis direction

[0160] d3 one side

[0161] d4 other side

[0162] F funnel

[0163] P1 upstream center point

[0164] P2 downstream center point

[0165] S1, S2 shortest distance

[0166] P3 area center