Throttle device and intake system for internal combustion engine

Abstract

To provide a throttle device that enables reduction in the number of components, simplification of the structure, reduction in the size, reduction in cost and the like, recovers fuel evaporation gas and can generate a turning flow in a combustion chamber.SOLUTION: A throttle device applied to an intake system of an internal combustion engine includes: a body 10 that defines a main passage 11a constituting a part of a main intake passage, an auxiliary passage 15 branched from the main passage and constituting a part of an auxiliary intake passage and a purge passage 16 constituting a part of a gas passage; an electric actuator 40 fixed to the body and having an output part 44 for outputting driving force; a throttle valve 30 for opening / closing the main passage; a first regulating valve 61a driven to regulate a flow rate of the auxiliary passage; a second regulating valve 61b driven to regulate a flow rate of the purge passage; and a transmission mechanism Gt disposed in the vicinity of the output part 44 to transmit the driving force of the output part to the throttle valve, the first regulating valve and the second regulating valve.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a throttle device applied to an internal combustion engine of a vehicle, such as a motorcycle, and an intake system of the internal combustion engine. [Background technology]

[0002] A known intake system for a conventional internal combustion engine includes an inlet pipe that defines the intake passage, an intake valve that opens and closes the intake passage at a position facing the combustion chamber, an injector provided in the inlet pipe to inject fuel midway through the intake passage, a throttle valve provided in the inlet pipe and driven by a drive mechanism to open and close the intake passage, a partition plate downstream of the throttle valve that divides the intake passage into an upper intake passage and a lower intake passage, and an intake distribution valve provided in the inlet pipe downstream of the throttle valve and adjacent to the upstream edge of the partition plate and driven by a separate drive mechanism, and the intake distribution valve is appropriately rotated to change the ratio of air flowing through the upper intake passage and the lower intake passage (see, for example, Patent Document 1). However, the above-mentioned intake system requires a drive mechanism for driving the throttle valve and a drive mechanism for driving the intake distribution valve, which increases the number of parts, complicates the structure, increases the size, and increases costs.

[0003] Other known intake systems include a canister that temporarily stores fuel evaporative gas generated in the fuel tank, a purge pipe that directs the evaporative gas from the canister to the intake passage of the internal combustion engine, and a purge valve equipped with a dedicated driving source downstream of the canister or midway through the purge pipe, in which the purge valve is appropriately controlled by the dedicated driving source to introduce the evaporative gas in the canister into the intake passage at a desired flow rate. These canister arrangement structures or fuel evaporative gas recovery devices are known (see, for example, Patent Documents 2 and 3). However, the above-mentioned canister arrangement structure or fuel evaporative gas recovery device requires a purge valve equipped with a dedicated drive source, which leads to an increase in the number of parts, an increase in size, and an increase in cost.

[0004] Furthermore, as another intake system, an intake system control device is known which includes a throttle valve that opens and closes the intake passage, a throttle body which includes an intake passage, a bypass passage and a purge passage, a flow path switching mechanism which switches the blocked state of the bypass passage and the purge passage by the driving force of the throttle valve, and a flow control valve which adjusts the flow rate of the bypass passage or the purge passage (for example, see Patent Document 4). However, in the above-mentioned intake system control device, the flow control valve is driven by a driving force separate from the driving force of the throttle valve, so a dedicated driving source is required, resulting in an increase in the number of parts, a complex structure, an increase in size, and high costs. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5925878 [Patent Document 2] JP 2012-7537 A [Patent Document 3] JP 2016-8014 A [Patent Document 4] JP 2010-19185 A Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above circumstances, and its object is to provide a throttle device and an intake system for an internal combustion engine which can recover fuel evaporative gas and generate swirling flows such as swirl flows and tumble flows in the combustion chamber, while reducing the number of parts, simplifying the structure, reducing costs, and making the device compact. [Means for solving the problem]

[0007] The throttle device of the present invention is a throttle device applied to the intake system of an internal combustion engine which includes a main intake passage which leads intake air to the combustion chamber, an auxiliary intake passage which branches off midway through the main intake passage and joins the main intake passage near the combustion chamber, and a gas passage which leads fuel evaporative gas to the main intake passage, and is configured to include a body which defines a main passage which is part of the main intake passage, a auxiliary passage which branches off from the main passage and is part of the auxiliary intake passage, and a purge passage which is part of the gas passage, an electric actuator having an output section fixed to the body and which outputs driving force, a throttle valve which opens and closes the main passage, a first regulating valve which is driven to adjust the flow rate of the auxiliary passage, and a second regulating valve which is driven to adjust the flow rate of the purge passage, and a transmission mechanism arranged in the vicinity of the output section to transmit the driving force of the output section to the throttle valve, the first regulating valve, and the second regulating valve.

[0008] In the above throttle device, a configuration may be adopted in which the electric actuator is a drive motor that generates a rotational drive force.

[0009] In the above throttle device, a configuration may be adopted in which the throttle valve is fixed to a throttle shaft supported rotatably on the body, the output part is a drive gear fixed to the rotating shaft of the drive motor, and the transmission mechanism includes a gear train interposed between the drive gear and the throttle shaft.

[0010] In the above throttle device, the throttle valve may be fixed to a throttle shaft rotatably supported by the body, and the transmission mechanism may include a rotating member fixed to one end of the throttle shaft and rotating integrally therewith, and an intervening member interposed between the rotating member and the first and second adjusting valves.

[0011] The above throttle device may include an adjustment rod that traverses the sub-passage and the purge passage, is rotatably supported by the body, and has a first adjustment valve and a second adjustment valve, and the intervening member is formed so as to rotate integrally with the adjustment rod.

[0012] In the above throttle device, a configuration may be adopted in which the rotating member is a first gear, and the intervening member is a second gear that meshes with the first gear.

[0013] In the above throttle device, a configuration may be adopted in which the transmission mechanism includes a throttle gear fixed to one end of the throttle shaft, and the first gear is disposed adjacent to the throttle gear.

[0014] In the above throttle device, a configuration may be adopted in which the throttle gear is a sector gear partially having a row of teeth, and the first gear is a sector gear partially having a row of teeth.

[0015] In the above throttle device, a configuration may be adopted in which the throttle gear and the first gear are integrally formed.

[0016] In the above throttle device, a configuration may be adopted in which the body includes a cylindrical portion extending in the direction of a predetermined first center line to define a main passage, the throttle shaft is rotatably supported by the body on a first axis perpendicular to the first center line, and the adjustment rod is rotatably supported by the body on a second axis parallel to the first axis.

[0017] In the above throttle device, a configuration may be adopted in which the adjustment rod is formed in a cylindrical shape having a circular cross section, the first adjustment valve includes a first cutout portion formed in the adjustment rod in a region facing the auxiliary passage, and the second adjustment valve includes a second cutout portion formed in the adjustment rod in a region facing the purge passage.

[0018] In the above throttle device, a configuration may be adopted in which the first hollow portion is a notched groove formed by cutting out the adjustment rod, and the second hollow portion is a through hole that passes through the adjustment rod.

[0019] In the above throttle device, a configuration may be adopted in which the body includes a cylindrical portion extending in the direction of a predetermined first center line to define a main passage, and a motor accommodating portion adjacent to the cylindrical portion to accommodate a drive motor, and the sub-passage and purge passage are formed in the area between the cylindrical portion and the motor accommodating portion.

[0020] In the above throttle device, a configuration may be adopted in which the motor accommodating portion defines a cylindrical recess extending in the direction of a predetermined second center line, the second center line being oriented in a direction perpendicular to the first center line.

[0021] In the above throttle device, when the throttle valve moves from a low opening to a medium opening and then to a full opening, the first adjusting valve opens the by-passage in the low to medium opening range and closes the by-passage in the full opening range, and the second adjusting valve closes the purge passage in the low opening range and opens the purge passage toward the full opening.

[0022] In the above throttle device, a configuration may be adopted in which the sub-passage includes a branch port branching off from the main passage upstream of the throttle valve, and the purge passage includes an inlet port downstream of the throttle valve for introducing fuel evaporative gas into the main passage.

[0023] In addition, the intake system of the internal combustion engine of the present invention comprises a main intake pipe defining a part of the main intake passage which leads intake air to the combustion chamber of the internal combustion engine, a fuel injection valve which injects fuel into the main intake passage or into the combustion chamber, an auxiliary intake pipe defining a part of an auxiliary intake passage which branches off from the main intake passage and joins the main intake passage near the combustion chamber, a gas piping which defines a part of a gas passage which leads fuel evaporative gas in the fuel tank to the main intake passage, and a throttle device arranged in the main intake pipe, and any of the throttle devices having the above-mentioned configurations is adopted as the throttle device. Effect of the Invention

[0024] The throttle device and internal combustion engine intake system configured as described above can reduce the number of parts, simplify the structure, make the device smaller, and reduce costs, while also recovering evaporated fuel gas and generating swirling flows such as swirl flows and tumble flows in the combustion chamber, thereby contributing to improved combustion efficiency. [Brief description of the drawings]

[0025] [Figure 1] 1 is a system diagram showing an intake system of an internal combustion engine equipped with a throttle device according to an embodiment of the present invention. [Diagram 2] 1 is a perspective view of a throttle device according to one embodiment, viewed obliquely from the upstream side. FIG. [Diagram 3] 1 is a perspective view of a throttle device according to one embodiment, viewed obliquely from the downstream side. [Figure 4] 1 is an exploded perspective view of a throttle device according to an embodiment of the present invention, viewed from one side; [Diagram 5] FIG. 4 is an exploded perspective view of the throttle device according to the embodiment, as viewed from the other side. [Figure 6] 1 is a perspective cross-sectional view of a throttle device according to one embodiment, taken along a plane including a first center line of a main passage that forms a part of a main intake passage and a first axis line of a throttle shaft. [Figure 7] 1 is a perspective cross-sectional view of a throttle device according to one embodiment, taken along a plane that includes a first center line of a main passage that forms a part of a main intake passage and is perpendicular to a first axis of a throttle shaft. [Figure 8] 1 is a perspective cross-sectional view of a throttle device according to one embodiment, taken along a plane that is perpendicular to a first axis of a throttle shaft and passes through an auxiliary passage that forms part of the auxiliary intake passage; [Figure 9] 1 is a perspective cross-sectional view of a throttle device according to one embodiment, taken along a plane perpendicular to a first axis of a throttle shaft and passing through a purge passage that forms part of a gas passage. [Figure 10] FIG. 2 is a partially perspective view showing the arrangement relationship between a sub-passage and a purge passage in a throttle device according to one embodiment; [Figure 11]4 is a perspective cross-sectional view of a throttle device according to one embodiment, taken along a plane including a second axis of an adjustment rod and parallel to a first center line of a main passage. FIG. [Figure 12] 1 is a perspective view showing an output portion (drive gear) of a drive motor serving as an electric actuator and a transmission mechanism (gear train) that transmits the drive force of the output portion in a throttle device according to one embodiment. FIG. [Figure 13] 1 is a perspective view showing an adjustment rod having a first adjustment valve and a second adjustment valve and integrally provided with a second gear (intervening member) in a throttle device according to one embodiment. FIG. [Figure 14] 4 is a table showing the relationship of the opening degree of a first adjusting valve and the opening degree of a second adjusting valve to the opening degree of a throttle valve in a throttle device according to one embodiment. [Figure 15] 5 is a graph showing the flow rate through a main passage, the flow rate through a sub-passage, and the flow rate through a purge passage relative to the opening degree of a throttle valve in a throttle device according to one embodiment. [Figure 16] FIG. 4 is a system diagram showing an intake system of an internal combustion engine according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. A throttle device M according to one embodiment is incorporated into an intake system of an internal combustion engine mounted on a motorcycle, for example. As shown in Fig. 1, the motorcycle includes an internal combustion engine E, a fuel tank T, and other components (not shown).

[0027] The internal combustion engine E includes a cylinder block 1, a piston 2, a cylinder head 3, an intake valve 4a, an exhaust valve 4b, an exhaust pipe 5, an intake system IS, and the like. The cylinder head 3 cooperates with the upper surface of the piston 2 to define a combustion chamber C, and has an intake port 3a which forms part of the main intake passage, a secondary port 3b which forms part of the secondary intake passage, and an exhaust port 3c, and also houses a drive mechanism (not shown) which opens and closes the intake valve 4a and the exhaust valve 4b, an ignition plug (not shown), etc.

[0028] The auxiliary port 3b is formed to merge with the intake port 3a immediately upstream of the intake valve 4a. That is, the auxiliary intake passage (auxiliary port 3b) has a merging port 3b1 that merges with the main intake passage (intake port 3a) upstream of the intake valve 4a. The confluence port 3b1 of the sub-port 3b is oriented in a direction that generates a swirl flow (horizontal vortex) in the combustion chamber C. Specifically, the confluence port 3b1 of the sub-port 3b is formed so that it joins the intake port 3a from an oblique direction and the intake air flows in a tangential direction to the inner wall surface of the combustion chamber C.

[0029] The intake system IS includes an intake port 3a and an auxiliary port 3b in the cylinder head 3, an air cleaner Ac that draws in outside air, a main intake pipe Ip, an auxiliary intake pipe Sp, a fuel injection valve Iv arranged in the middle of the main intake pipe Ip, a throttle device M arranged in the middle of the main intake pipe Ip upstream of the fuel injection valve Iv, a gas piping Gp that connects the fuel tank T and the throttle device M, and a canister Ca arranged in the middle of the gas piping.

[0030] The main intake pipe Ip is formed from a metal or resin material, etc., and defines a main intake passage Ip1 having a substantially circular cross-section for passing the intake air sucked in by the air cleaner Ac, and is positioned so as to be interposed between the air cleaner Ac and the intake port 3a of the cylinder head 3. The auxiliary intake pipe Sp is formed from a metal, resin, rubber material, or the like, and defines an auxiliary intake passage Sp1 having a circular cross section to allow intake air to pass through. Its upstream end is connected to a connector 15b that defines a part of the auxiliary passage 15 provided in the throttle device M, and its downstream end is connected to a connector (not shown) that leads to the auxiliary port 3b of the cylinder head 3. The fuel injection valve Iv is disposed in the main intake pipe Ip and injects fuel into the main intake passage Ip1 near the intake port 3a. The gas pipe Gp defines a gas passage Gp1 and connects the fuel tank T and the canister Ca, and is disposed so as to connect the canister Ca and a pipe 16b that defines a part of a purge passage provided in the throttle device M. The canister Ca contains activated carbon that temporarily adsorbs the fuel evaporation gas guided from the fuel tank T, and guides the stored fuel evaporation gas to a gas passage Gp1 while also taking in outside air according to the internal pressure.

[0031] 2 to 6, the throttle device M includes a body 10, a throttle shaft 20, a throttle valve 30, a drive motor 40 serving as an electric actuator, a gear train Gt serving as a transmission mechanism, an adjustment rod 60, and a sensor unit U. Here, as shown in FIG. 5, the sensor unit U includes a case U1, a joint surface U2, a terminal U3 for connecting the drive motor 40, a fitting receiving portion U4 for fitting the end of the spindle 12b1 and for slidably receiving the end face of the double gear 51, an angular position sensor 70, a pressure sensor 80, a temperature sensor 90, and a circuit board (not shown) carrying various electronic components. The gear train Gt is made up of a two-stage gear 51 (large diameter gear 51a, small diameter gear 51b), a two-stage gear 52 (large diameter gear 52a as a throttle gear, small diameter gear 52b as a first gear), and a second gear 62.

[0032] The body 10 is formed from a metal material such as aluminum or a resin material, and, as shown in Figures 2 to 11, is provided with a cylindrical portion 11, a flange portion 12, a motor accommodating portion 13, a shaft hole 14 through which the throttle shaft 20 passes, a sub-passage 15, a purge passage 16, a fitting hole 17, a communication passage 18, and an insertion hole 19.

[0033] The cylindrical portion 11 extends in the direction of a first center line L1, defines a main passage 11a, and is provided with an upstream connection portion 11b and a downstream connection portion 11c at both ends. The main passage 11a functions as a part of a main intake passage that guides intake air to the combustion chamber C, and is formed in a cylindrical shape having a circular cross section centered on the first center line L1. The upstream connection part 11b is connected to the upstream main intake pipe Ip connected to the air cleaner Ac, and the downstream connection part 11c is connected to the downstream main intake pipe Ip connected to the surrounding area of ​​the intake port 3a of the cylinder head 3 of the internal combustion engine E.

[0034] As shown in Figures 4 to 6, the flange portion 12 is an area that joins and fastens the sensor unit U and accommodates the gear train Gt (transmission mechanism) inside, and has a joining surface 12a, a recess 12b, a recess 12c, a recess 12d, and a recess 12e. The joint surface 12a is a flat surface to which the joint surface U2 of the sensor unit U is joined, and includes four screw holes 12a1 into which the screws b1 are screwed in. Furthermore, an insertion hole 19 through which the temperature sensor 90 is inserted is opened in the joint surface 12a. The recess 12b is an area that rotatably houses the double gear 51 and the second gear 62 that form part of the gear train Gt, and is provided with a support shaft 12b1 that supports the double gear 51, and is also provided with a fitting hole 17. The recess 12b is also provided with two screw holes 12b2 around the cylindrical recess 13a, into which screws b2 that fix the flange portion 42 of the drive motor 40 are screwed. The recess 12c is an area that rotatably accommodates a two-stage gear 52 that is fixed to one end 23 of the throttle shaft 20 and forms part of the gear train Gt. The recess 12d is an area where the pressure sensor 80 of the sensor unit U faces, and the communication passage 18 opens therein. The recess 12e is an area that rotatably accommodates the cylindrical portion 52c of the double gear 52 that is a part of the gear train Gt.

[0035] The motor accommodating section 13 is an area that accommodates the drive motor 40, and includes a cylindrical recess 13a that extends in the direction of the second center line L2. Here, the second center line L2 is oriented in a direction perpendicular to the first center line L1. That is, the cylindrical recess 13a is disposed adjacent to the cylindrical portion 11 and extends in a direction twisted with respect to the extension direction of the cylindrical portion 11 so as to be adjacent to and overlap the cylindrical portion 11. This allows the motor accommodating section 13 to be disposed on the same side as the cylindrical portion 11 with respect to the flange portion 12, which contributes to the miniaturization and integration of the body 10.

[0036] 6, the shaft hole 14 is formed as a circular hole through which the throttle shaft 20 passes and which supports the throttle shaft 20 rotatably on the first axis S1. Note that a dedicated bush as a bearing for supporting the throttle shaft 20 and / or a lip-type seal for sealing around the throttle shaft 20 may be disposed in the shaft hole 14 as necessary.

[0037] 7 and 8, the auxiliary passage 15 is formed in the region between the cylindrical portion 11 and the motor housing portion 13, and has a branch port 15a that branches off from the main passage 11a upstream of the throttle valve 20. The auxiliary passage 15 also has its downstream region defined by a connector 15b that is fitted into the body 10 and to which the auxiliary intake pipe Sp is connected.

[0038] 7 and 9, the purge passage 16 is formed in the region between the cylindrical portion 11 and the motor housing portion 13, and has an inlet 16a that introduces fuel evaporation gas into the main passage 11a downstream of the throttle valve 20. The upstream region of the purge passage 16 is also defined by a connector 16b that is fitted into the body 10 and to which the gas pipe Gp is ​​connected.

[0039] That is, the sub-passage 15 and the purge passage 16 are disposed in the region between the cylindrical portion 11 and the motor accommodating portion 13 and are disposed adjacent to each other, as shown in Fig. 10. This contributes to the miniaturization and integration of the body 10, and also makes it possible to easily arrange the fitting hole 17 into which the adjustment rod 60 that traverses the sub-passage 15 and the purge passage 16 is fitted.

[0040] 8, 9 and 11, the fitting hole 17 is formed as a circular hole centered on a second axis S2 parallel to the first axis S1, and communicates with the sub-passage 15 and the purge passage 16 by crossing them. The fitting hole 17 fits an adjustment rod 60 and supports the adjustment rod 60 rotatably on the second axis S2.

[0041] As shown in Figures 3, 4, 7 and 8, the communication passage 18 opens into the recess 12d to connect the pressure sensor 80 to the main passage 11a, and has an opening 18a that opens into the main passage 11a at a position downstream of the throttle valve 30 and away from the inlet 16a of the purge passage 16. In this way, since the opening 18a of the connecting passage 18 is positioned away from the inlet 16a of the purge passage 16, the influence of the fuel evaporative gas introduced from the inlet 16a can be suppressed, and therefore the pressure of the intake air flowing through the main passage 11a can be detected with high accuracy.

[0042] As shown in FIGS. 2 and 7, the insertion hole 19 allows the temperature sensor 90 to be inserted and the tip region of the temperature sensor 90 to protrude into the main passage 11a, and has an opening 19a that opens into the main passage 11a at a position upstream of the throttle valve 30 and away from the branch port 15a of the sub-passage 15. In this way, since the opening 19a of the insertion hole 19 is positioned away from the branch port 15a of the secondary passage 15, the influence of the intake air flow branched off from the branch port 15a can be suppressed, and therefore the temperature of the intake air flowing through the main passage 11a can be detected with high accuracy.

[0043] The throttle shaft 20 is made of a metal material or the like and is formed so as to have a circular cross section and extend in the direction of the first axis S1, as shown in Figures 4 and 5, and, as shown in Figure 6, is provided with a slit 21 in the central region for fitting the throttle valve 30, two screw holes 22, and one end 23 into which a two-stage gear 52 that forms part of the gear train Gt is fitted and fixed. Further, on the outer periphery of the region of the slit 21, a two-face width portion 21a is formed in order to reduce the passage resistance in the main passage 11a. The throttle shaft 20 is inserted through the shaft hole 14 of the body 10, and the throttle valve 30 fitted in the slit 21 is fastened by a screw b3, thereby fixing the throttle valve 30 so that it can be opened and closed freely.

[0044] The throttle valve 30 is a butterfly valve made of a metal material or the like and formed into a substantially circular disk shape, and as shown in FIGS. 4 to 6, is provided with a circular hole 31 through which a screw b3 passes. After the throttle shaft 20 is inserted into the shaft hole 14, the throttle valve 30 is passed through the slit 21 and fixed to the throttle shaft 20 by a screw b3, and is disposed so as to open and close the main passage 11a.

[0045] As shown in Figures 4 and 5, the drive motor 40 includes a main body 41, a flange portion 42, a rotating shaft 43 that rotates around the second center line L2, a drive gear 44 fixed to the rotating shaft 43 as an output portion that outputs driving force, and a terminal 45 that is connected to the terminal U3 of the sensor unit U. The main body 41 is formed in a cylindrical shape with a bottom and centered on the second center line L2 so as to be fitted into the cylindrical recess 13a. The flange portion 42 has two circular holes 42a through which the screws b2 pass, and with the main body 41 inserted into the cylindrical recess 13a and abutted against the bottom wall of the recess 12b around the cylindrical recess 13a, the screws b2 are screwed into the screw holes 12b2 of the body 10 to fasten and fix the main body 41 in place.

[0046] As shown in FIG. 12, double gear 51 constitutes a part of the transmission mechanism, and is made of a resin material so as to integrally include large diameter gear 51a and small diameter gear 51b. The double gear 51 is supported in a freely rotatable manner by a support shaft 12b1 parallel to the first axis S1 and the second axis S2 in the area of ​​the recess 12b of the body 10, with the large diameter gear 51a meshing with the drive gear 44 of the drive motor 40 and the small diameter gear 51b meshing with the large diameter gear 52a of the double gear 52.

[0047] As shown in FIG. 12, the double gear 52 forms part of the transmission mechanism and is formed from a resin material so as to integrally include a large diameter gear 52a, a small diameter gear 52b, a cylindrical portion 52c, and an annular recess 52d. Here, the large diameter gear 52a functions as a throttle gear fixed to one end 23 of the throttle shaft 20, and is formed as a sector gear partially having a row of teeth. The small diameter gear 52b functions as a rotating member that is fixed to one end 23 of the throttle shaft 20 and rotates integrally therewith, that is, as a first gear, and is formed as a sector gear partially having a row of teeth. The cylindrical portion 52c is a region into which one end 23 of the throttle shaft 20 is fitted and fixed. The annular recess 52d has a permanent magnet (not shown) embedded in its inner circumferential surface, and is formed to receive the angular position sensor 70 of the sensor unit U in a non-contact manner, as shown in FIG.

[0048] The double gear 52 is fixed to one end 23 of the throttle shaft 20, and is supported so as to be freely rotatable around the first axis S1, with the large diameter gear 52a meshing with the small diameter gear 51b of the double gear 51 in the area of ​​the recesses 12c, 12b, and the small diameter gear 52b, acting as the first gear, meshing with the second gear 62, acting as an intervening member that rotates integrally with the adjustment rod 60. In this way, the large diameter gear 52a as the throttle gear and the small diameter gear 52b as the first gear are arranged adjacent to each other at one end 23 of the throttle shaft 20 (here, they are formed integrally), which contributes to miniaturization by consolidating parts. In addition, the large diameter gear 52a as the throttle gear and the small diameter gear 52b as the first gear are formed as sector gears having partial tooth rows, so that the parts that do not function as gears can be eliminated and the gears themselves can be made compact. Therefore, the double gear 52 can be housed in a narrow area (recess 12c) of the body 10, and the throttle device M as a whole can be made compact.

[0049] The adjustment rod 60 is made of a resin material and is formed so as to integrally include a rod portion 61 and a second gear 62, as shown in FIGS. The rod portion 61 is formed in a cylindrical shape having a circular cross section that extends about the second axis S2, and has a first adjusting valve 61a and a second adjusting valve 61b. As shown in FIGS. 8 and 11, the first adjustment valve 61a is driven to adjust the flow rate of the secondary passage 15, and is formed as a substantially U-shaped notched groove as a first hollowed-out portion in a region facing the secondary passage 15. The second adjustment valve 61b is driven to adjust the flow rate of the purge passage 16, as shown in Figs. 9 and 11, and is formed in the through hole as a second hollow portion in a region facing the purge passage 16. That is, the adjustment rod 60 is fitted into the fitting hole 17 of the body 10 so as to cross the secondary passage 15 and the purge passage 16 and rotates on the second axis S2, whereby the first adjustment valve 61a adjusts the flow rate of intake air flowing through the secondary passage 15 and the second adjustment valve 61b adjusts the flow rate of fuel evaporation gas flowing through the purge passage 16.

[0050] In this way, since a first adjusting valve 61a and a second adjusting valve 61b are provided for one adjusting rod 60, it is possible to reduce the number of parts, simplify the structure, and reduce costs compared to the case where a first adjusting valve and a second adjusting valve are provided for each separate adjusting rod. In addition, since a first adjustment valve 61a and a second adjustment valve 61b are provided for one adjustment rod 60, by appropriately selecting the hollowing out positions of the first adjustment valve 61a (first hollowing out portion) and the second adjustment valve 61b (second hollowing out portion) around the second axis S2, the phases of the opening and closing timing of the first adjustment valve 61a and the opening and closing timing of the second adjustment valve 61b can be appropriately selected according to the specifications of the intake control of the internal combustion engine E, and each opening and closing timing can be linked to the opening and closing operation of the throttle valve 30. Furthermore, since the first adjustment valve 61a has the form of a notched groove as a first hollow portion, and the second adjustment valve 61b has the form of a through hole as a second hollow portion, it is possible to adopt a form appropriate for the flow rate of the fluid flowing through the secondary passage 15 and the flow rate of the fluid flowing through the purge passage 16, while also ensuring mechanical strength.

[0051] As described above, the gear train Gt (the two-stage gear 51, the two-stage gear 52, and the second gear 62) serving as the transmission mechanism is housed in one side portion (the recesses 12b and 12c) of the body 10 and is arranged in a plane in a direction perpendicular to the first axis S1. Therefore, it is possible to achieve a thinner throttle device M compared to an arrangement in which the gear train protrudes in the direction of the first axis S1.

[0052] As shown in Figures 5 and 6, the angular position sensor 70 is provided in the sensor unit U and is a non-contact sensor formed in a cylindrical shape with a Hall element embedded in it. It detects the rotation angle of the throttle shaft 20 in cooperation with a permanent magnet (not shown) arranged in the annular recess 52d of the double gear 52 fixed to the throttle shaft 20.

[0053] As shown in FIG. 5, the pressure sensor 80 is provided in a sensor unit U, and includes a pressure receiving portion such as a diaphragm having a semiconductor strain gauge, a protective cover, and the like. The pressure sensor 80 detects the pressure of the intake air through a communication passage 18 leading to the main passage 11a with the joint surface U2 of the sensor unit U joined to the joint surface 12a of the body 10 and the periphery of the recess 12d sealed by a seal member Sr. Here, the pressure sensor 80 receives the intake pressure through the opening 18a of the connecting passage 18 formed in an area away from the inlet 16a of the purge passage 16, so the intake pressure can be detected with high accuracy without being affected by the flow of fuel evaporative gas in the vicinity of the inlet 16a.

[0054] As shown in FIG. 5, the temperature sensor 90 is provided in the sensor unit U, and is a lead-type sensor including a temperature-sensing element such as a thermistor. The temperature sensor 90 is housed in a cylindrical portion protruding from the case U1 of the sensor unit U and is positioned so as to protrude into the main passage 11a through the insertion hole 19 upstream of the throttle valve 30, as shown in Figure 7, to detect the temperature of the intake air. Here, since the temperature sensor 90 is positioned so as to protrude into an area away from the branch port 15a of the secondary passage 15, it is possible to detect the temperature of the intake air without being affected by the flow of the intake air in the vicinity of the branch port 15a.

[0055] Next, the operation of the internal combustion engine E equipped with the above-described intake system IS will be described with reference to FIG. First, when the internal combustion engine E is in the idle operating range, the throttle valve 30 is in a closed state in which the main passage 11a is closed, the first regulating valve 61a opens the sub-passage 15, and the second regulating valve 61b closes the purge passage 16. Therefore, the intake air sucked in through the air cleaner Ac flows through the main intake passage (main intake passage Ip1, main passage 11a), then flows through the auxiliary intake passage (auxiliary intake passage 15, auxiliary intake passage Sp1, auxiliary port 3b) bypassing the throttle valve 30, and flows again into the downstream main intake passage (intake port 3a), and flows into the combustion chamber C as an air-fuel mixture together with the fuel injected by the fuel injection valve Iv in the main intake passage Ip1. As a result, a swirl flow (horizontal vortex) is generated in the mixture of the intake air and injected fuel flowing through the auxiliary intake passage (the auxiliary intake passage 15, the auxiliary intake passage Sp1, and the auxiliary port 3b) when the mixture flows into the combustion chamber C. This swirl flow promotes atomization of the fuel and homogenization of the mixture of the intake air and fuel, and stabilizes idle operation with a small amount of fuel.

[0056] When the internal combustion engine E is in the low to medium load operating range, the throttle valve 30 opens in the low opening range (10° to 30°) to open the main passage 11a. On the other hand, the first adjusting valve 61a fully opens the secondary passage 15 when the throttle valve 30 is positioned at a low opening (10°), and starts to narrow the secondary passage 15 when the throttle valve 30 is positioned at a medium opening (20° to 30°). The second adjusting valve 61b starts to open the purge passage 16 when the throttle valve 30 is positioned at a low opening (10°), and fully opens the purge passage 16 when the throttle valve 30 is positioned at a medium opening (20° to 30°). As a result, the amount of intake air flowing through the main intake passage (main intake passage Ip1, main passage 11a, main intake passage Ip1) increases, and the amount of intake air flowing through the auxiliary intake passage (auxiliary passage 15, auxiliary intake passage Sp1, auxiliary port 3b) increases, and fuel vapor flows into the main intake passage (main passage 11a) via the gas passage (gas passage Gp1, purge passage 16), generating a swirl flow (horizontal vortex) in the air-fuel mixture flowing into the combustion chamber C. This swirl flow promotes atomization of the fuel and homogenization of the air-fuel mixture in the low to medium load operating range, improving combustion efficiency.

[0057] When the internal combustion engine E is in a high load operating range, the throttle valve 30 opens fully (40° or more) to open the main passage 11a. On the other hand, the first adjusting valve 61a closes the sub-passage 15 when the throttle valve 30 is fully opened (40° or more). Also, the second adjusting valve 61b keeps the purge passage 16 fully open when the throttle valve 30 is fully opened (40° or more). As a result, in the high-load operating range, the amount of intake air flowing through the main intake passage (main intake passage Ip1, main passage 11a, main intake passage Ip1) is maximized, and fuel evaporative gas flows into the main intake passage (main passage 11a) via the gas passage (gas passage Gp1, purge passage 16), increasing the amount of intake air flowing through the main intake passage (main intake passage Ip1, main passage 11a, main intake passage Ip1), increasing the combustion speed, and promoting efficient combustion.

[0058] That is, as shown in FIG. 15, when the throttle valve 30 opens from the fully closed position to the fully open position, in the low to medium load operating range (where the opening angle of the throttle valve 30 is in the range of 0° to 20°), the proportion of intake air flowing through the auxiliary intake passage (the auxiliary intake passage 15, the auxiliary intake passage Sp1, and the auxiliary port 3b) increases. In addition, in the medium to high load operating range (when the opening angle of the throttle valve 30 is in the range of 30° to 40°), the proportion of intake air flowing through the auxiliary intake passages (auxiliary intake passage 15, auxiliary intake passage Sp1, auxiliary port 3b) decreases, and the proportion of intake air flowing through the main intake passages (main intake passage Ip1, main passage 11a, main intake passage Ip1) increases. Furthermore, in the low load to high load operating range, the flow rate of fuel evaporative gas introduced from the gas passage (gas passage Gp1, purge passage 16) to the main intake passage (main passage 11a) gradually increases. Therefore, in the low load to medium load operating range, a swirl flow is generated in the combustion chamber C, improving the combustion efficiency, and in the high load operating range, the flow rate of high-speed intake air mainly flowing through the main passage 11a increases, increasing the combustion speed and promoting efficient combustion.

[0059] In short, with regard to the opening and closing timing between the throttle valve 30, the first adjusting valve 61a, and the second adjusting valve 61b, when the throttle valve 30 moves from a low opening to a medium opening and then to a full opening, the first adjusting valve 61a opens the auxiliary passage 15 in the low to medium opening range and closes the auxiliary passage 15 in the full opening range, and the second adjusting valve 61b closes the purge passage 16 in the low opening range and opens the purge passage 16 toward the full opening.

[0060] The throttle device M having the above-mentioned configuration includes a body 10 that defines a main passage 11a that forms part of the main intake passage, a sub-passage 15 that branches off from the main passage 11a and forms part of the sub-intake passage, and a purge passage 16 that forms part of the gas passage, an electric actuator (drive motor 40) having an output section (drive gear 44) fixed to the body 10 and that outputs a driving force, a throttle valve 30 that opens and closes the main passage 11a, a first adjusting valve 61a that is driven to adjust the flow rate of the sub-passage 15, a second adjusting valve 61b that is driven to adjust the flow rate of the purge passage 16, and a transmission mechanism (gear train Gt) arranged in the vicinity of the output section (drive gear 44) to transmit the driving force of the output section (drive gear 44) to the throttle valve 30, the first adjusting valve 61a, and the second adjusting valve 61b.

[0061] According to this, the throttle valve 30, the first adjusting valve 61a and the second adjusting valve 61b are driven by the driving force of a single electric actuator, so that compared to the conventional case in which multiple electric actuators are used and driven individually, it is possible to reduce the number of parts, simplify the structure, reduce costs, etc., while also recovering fuel evaporative gas and generating a swirling flow in the combustion chamber, thereby improving combustion efficiency. In particular, by adopting a transmission mechanism (gear train Gt) arranged near the output part (drive gear 44) of the electric actuator (drive motor 40), the parts can be concentrated and arranged on one side of the body 10, thereby achieving an overall compact size.

[0062] In addition, by adopting the drive motor 40 as the electric actuator and adopting the gear train Gt (two-stage gear 51, two-stage gear 52, second gear 62) that meshes with the drive gear 44 of the drive motor 40 as the transmission mechanism, the gear train Gt can be concentrated and arranged on one side of the body 10 (the inner area of ​​the flange portion 12), thereby achieving the miniaturization of the entire throttle device M.

[0063] As described above, the throttle device M of the present invention can achieve a reduction in the number of parts, a simplified structure, a compact size, low costs, etc., while recovering evaporated fuel gas and generating a swirl flow (rotating flow) in the combustion chamber C, thereby contributing to improving the combustion efficiency in the internal combustion engine E.

[0064] As described above, in the intake system IS equipped with the throttle device M according to one embodiment, the confluence port 3b1 of the auxiliary intake passage (auxiliary port 3b) is oriented upstream of the intake valve 4a in a direction that generates a swirl flow in the combustion chamber C, but this is not limited to this. For example, as shown in FIG. 16, a configuration may be adopted in which the fuel injection valve Iv is positioned to inject fuel directly into the combustion chamber C, and the confluence port 113b1 of the auxiliary intake passage (auxiliary port 113b) is oriented upstream of the intake valve 4a in a direction that generates a tumble flow (vertical vortex) in the combustion chamber C. This makes it possible to reduce the number of parts, simplify the structure, make the engine smaller, and reduce costs, while also recovering evaporated fuel gas and generating a tumble flow (swirling flow) in the combustion chamber C, thereby contributing to improving the combustion efficiency of the internal combustion engine E.

[0065] In the above embodiment, the driving motor 40 that generates a rotational driving force is shown as the electric actuator, and the gear train Gt is shown as the transmission mechanism, but the present invention is not limited to this. For example, a solenoid equipped with a rod whose tip that extends in one direction is an output part may be used, and multiple link members connected to the output part of the rod, or link members and gears, may be used as the transmission mechanism. In addition, the term "electric actuator" is intended to include anything that converts electrical energy into physical momentum, and therefore is not limited to the drive motors and solenoids described above, but may be any other structure as long as it has an output section that generates a drive force.

[0066] In the above embodiment, the transmission mechanism employs the first gear 52b as a rotating member fixed to one end 23 of the throttle shaft 20 and rotating therewith, and the second gear 62 as an intervening member interposed between the rotating member and the first and second adjusting valves, but this is not limited to this, and two pulleys and a wound belt may be used as the rotating member and the intervening member, or two sprockets and a wound chain may be used as the rotating member and the intervening member.

[0067] In the above embodiment, the large diameter gear 52a as the throttle gear and the small diameter gear 52b as the first gear are integrally formed as the two-stage gear 52, but this is not limited to this, and a configuration in which they are formed as two separate gears and fixed adjacent to one end 23 of the throttle shaft 20 may also be adopted.

[0068] In the above embodiment, a configuration is shown in which the first adjustment valve 61a, the second adjustment valve 61b, and the second gear 62 are formed integrally with one adjustment rod 60, but this is not limited to this. The first adjustment valve and the second gear may be provided on one adjustment rod, and the second adjustment valve and another second gear may be provided on another adjustment rod, and the driving force may be transmitted separately. In addition, a first adjusting valve 61a including a notched groove formed in the rod portion 61 of the adjustment rod 60 is used as the first adjusting valve, and a first adjusting valve 61a including a through hole formed in the rod portion 61 of the adjustment rod 60 is used as the second adjusting valve, but this is not limited to this, and a form including a notched groove may be used for both, or a form including a through hole may be used for both, or a form such as a butterfly valve may be used for both.

[0069] In the above embodiment, a configuration has been shown in which two cutouts are formed in one adjustment rod 60 to provide the first adjustment valve 61a and the second adjustment valve 61b, and one sub-passage 15 and one purge passage 16 are provided, but this is not limited to this. A configuration may be adopted in which three or more cutouts are formed in one adjustment rod in the direction of the second axis S2, and in addition to the first adjustment valve and the second adjustment valve, for example, a third adjustment valve and a fourth adjustment valve are provided, thereby increasing the number of sub-passages or purge passages. In addition, in the above embodiment, the adjustment rod 60 made of a resin material is shown as the adjustment rod, but this is not limited to this, and an adjustment rod made of a metal material or other material may also be used.

[0070] In the above embodiment, the second axis S2 of the adjusting rod 60 is arranged parallel to the first axis S1 of the throttle valve 20, but the present invention is not limited to this, and the second axis of the adjusting rod may be arranged in a direction intersecting or parallel to the first axis by using a bevel gear or the like in the gear train as the transmission mechanism. In this case, the degree of freedom in the arrangement positions and directions of the sub-passage and the purge passage is increased, and various shapes can be adopted for the body.

[0071] In the above embodiment, the vehicle equipped with an internal combustion engine to which the throttle device and intake system of the present invention are applied is shown to be a motorcycle, but this is not limited to this and the vehicle may be applied to an internal combustion engine installed in an automobile, etc.

[0072] As described above, the throttle device and internal combustion engine intake system of the present invention achieves a reduction in the number of parts, a simplified structure, a smaller size, and lower costs, while recovering evaporated fuel gas and generating a swirl flow or tumble flow (rotating flow) in the combustion chamber, contributing to improved combustion efficiency, and is therefore applicable not only to internal combustion engines mounted on motorcycles, etc., but also to internal combustion engines mounted on automobiles or other vehicles. [Explanation of symbols]

[0073] E. Internal combustion engine T Fuel Tank IS intake system Ip main intake pipe Ip1 main intake passage Sp Auxiliary intake pipe Sp1 auxiliary intake passage Gp Gas piping Gp1 gas passage Ca canister IV Fuel Injection Valve C. Combustion chamber 3a Intake port (main intake passage) 3b, 113b Secondary port (secondary intake passage) 3b1, 113b1 auxiliary intake passage junction 4a Intake valve M Throttle Device 10. Body 11 Cylindrical part L1 1st center line 11a Main passage (main intake passage) 12 Flange 12b, 12c, 12e Concave portions (near the output portion of the electric actuator) 13 Motor housing 13a Cylindrical recess L2 2nd center line 15 Auxiliary passage (auxiliary intake passage) 15a Branch 15b Connector 16 Purge passage (gas passage) 16a Introduction 16b Connector 17 Fitting hole 18 Communication path 18a opening 19 Insertion hole 19a opening 20 Throttle shaft S1 1st axis 23 One end 30 Throttle valve 40 Drive motor (electric actuator) 43 Rotational Axis 44 Drive gear (output section) Gt Gear train (transmission mechanism) 51 Double Gear 51a Large diameter gear 51b Small diameter gear 52a Large diameter gear (throttle gear) 52b Small diameter gear (rotating member, first gear) 60 Adjustment rod S2 2nd axis 61 Rod section 61a First adjusting valve 61b Second adjusting valve 62 Second gear (intervening member) U Sensor unit 70 Angular Position Sensor 80 Pressure Sensor 90 Temperature Sensor

Claims

1. A throttle device applied to an intake system of an internal combustion engine, the throttle device including a main intake passage that introduces intake air into a combustion chamber, an auxiliary intake passage that branches off from the main intake passage midway and joins the main intake passage near the combustion chamber, and a gas passage that introduces fuel evaporative gas into the main intake passage, a body defining a main passage that is a part of the main intake passage, a secondary passage that branches off from the main passage and is a part of the secondary intake passage, and a purge passage that is a part of the gas passage; an electric actuator having an output unit fixed to the body and outputting a driving force; a throttle valve that opens and closes the main passage; a first adjusting valve that is actuated to adjust a flow rate of the secondary passage; a second adjusting valve that is actuated to adjust the flow rate of the purge passage; a transmission mechanism disposed near the output portion so as to transmit a driving force of the output portion to the throttle valve, the first adjusting valve, and the second adjusting valve; A throttle device including:

2. The electric actuator is a drive motor that generates a rotational drive force.

2. The throttle device according to claim 1.

3. The throttle valve is fixed to a throttle shaft that is rotatably supported by the body, the output portion is a drive gear fixed to a rotation shaft of the drive motor, the transmission mechanism includes a gear train interposed between the drive gear and the throttle shaft; 3. The throttle device according to claim 2.

4. The throttle valve is fixed to a throttle shaft that is rotatably supported by the body, the transmission mechanism includes a rotating member fixed to one end of the throttle shaft and rotating integrally therewith, and an intervening member interposed between the rotating member and the first adjusting valve and between the transmission mechanism and the throttle shaft and between the rotating member and the first adjusting valve and the second adjusting valve.

2. The throttle device according to claim 1.

5. an adjusting rod that crosses the sub-passage and the purge passage and is rotatably supported by the body and has the first adjusting valve and the second adjusting valve; The intervening member is formed to rotate integrally with the adjustment rod.

5. The throttle device according to claim 4.

6. the rotating member is a first gear, The intermediate member is a second gear that meshes with the first gear.

6. The throttle device according to claim 5.

7. the transmission mechanism includes a throttle gear fixed to one end of the throttle shaft, The first gear is disposed adjacent to the throttle gear.

7. The throttle device according to claim 6.

8. The throttle gear is a sector gear having a partial row of teeth, The first gear is a sector gear having a partial row of teeth.

8. The throttle device according to claim 7.

9. The throttle gear and the first gear are integrally formed.

9. The throttle device according to claim 8.

10. The body includes a tubular portion extending in a direction of a first predetermined centerline to define the main passage; the throttle shaft is rotatably supported by the body on a first axis perpendicular to the first center line, The adjustment rod is supported by the body so as to be rotatable on a second axis parallel to the first axis.

6. The throttle device according to claim 5.

11. The adjustment rod is formed in a cylindrical shape having a circular cross section, the first adjusting valve includes a first recessed portion formed in the adjusting rod in a region facing the sub-passage, the second adjustment valve includes a second recessed portion formed in the adjustment rod in a region facing the purge passage, 6. The throttle device according to claim 5.

12. The first hollow portion is a notched groove formed by cutting out the adjustment rod, The second hollow portion forms a through hole through which the adjustment rod passes.

12. The throttle device according to claim 11.

13. the body includes a cylindrical portion extending in a direction of a predetermined first center line to define the main passage, and a motor accommodating portion adjacent to the cylindrical portion to accommodate the drive motor; the sub-passage and the purge passage are formed in a region between the cylindrical portion and the motor accommodating portion, 3. The throttle device according to claim 2.

14. the motor housing defines a cylindrical recess extending in a direction of a second predetermined centerline; The second centerline is oriented perpendicular to the first centerline.

14. The throttle device according to claim 13.

15. When the throttle valve goes from a low opening to a medium opening to a full opening, the first adjusting valve opens the bypass passage in a range from the low opening degree to the medium opening degree and closes the bypass passage in a range of the full opening degree, the second adjusting valve closes the purge passage in the low opening region and opens the purge passage toward the full opening region, 2. The throttle device according to claim 1.

16. the sub-passage includes a branch port branching off from the main passage upstream of the throttle valve, the purge passage includes an inlet for introducing fuel evaporative gas into the main passage downstream of the throttle valve, 2. The throttle device according to claim 1.

17. a main intake pipe defining a part of a main intake passage that introduces intake air into a combustion chamber of an internal combustion engine; a fuel injection valve that injects fuel into the main intake passage or into the combustion chamber; an auxiliary intake pipe that defines a part of an auxiliary intake passage that branches off from the middle of the main intake passage and joins the main intake passage near the combustion chamber; a gas pipe defining a part of a gas passage that guides fuel evaporative gas in a fuel tank to the main intake passage; a throttle device disposed midway along the main intake pipe, The throttle device is a throttle device according to any one of claims 1 to 16. An intake system for an internal combustion engine.

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