Secondary air supply system

Abstract

To provide a structure that enables reduction in the number of components, cost reduction, increase in flexibility of layout, reduction in noise and the like in a secondary air supply system.SOLUTION: In a secondary air supply system for an engine for supplying air in an air cleaner 10 to an exhaust passage via an internal passage 21 of an on-off valve V1 having a drive part 50, the air cleaner 10 includes a through hole 11a penetrating through a wall part thereof. The on-off valve V1 is disposed in a region of the through hole 11e so that at least the drive part 50 and an upstream opening end 21u of the internal passage 21 face inside of the air cleaner 10 and a downstream opening end 21d of the internal passage 21 faces outside of the air cleaner 10 and is fixed to a wall part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a secondary air supply system for supplying air that has passed through an air cleaner to an exhaust passage in an intake and exhaust system of an engine mounted on a vehicle, particularly a motorcycle or the like. [Background technology]

[0002] A known conventional secondary air supply system is configured between the air cleaner and exhaust pipe of an engine mounted on a motorcycle, and includes a solenoid valve (opening / closing valve) fixed to the outer wall of the air cleaner, a reed valve fixed to the outer wall of the air cleaner, upstream piping connecting the air cleaner and the solenoid valve to allow air to pass through, intermediate piping connecting the solenoid valve and the reed valve to allow air to pass through, and downstream piping connecting the reed valve and the exhaust pipe to allow air to pass through (see, for example, Patent Document 1).

[0003] In this secondary air supply system, the solenoid valve and the air cleaner are connected by dedicated piping, which requires dedicated piping space, reducing layout flexibility, increasing the number of parts and costs, and making it difficult to consolidate the installed parts.In addition, the operating noise of the solenoid valve is a concern.

[0004] Another known secondary air supply system is one that is located between the air cleaner and exhaust pipe of an engine mounted on a motorcycle and includes a secondary air valve (open / close valve) fixed to the air cleaner in an area facing the top surface of the cylinder head cover, a secondary air intake hose that connects the secondary air valve to the air cleaner to allow air to pass through, and a secondary air supply hose that connects a connector provided on the cylinder head cover to communicate with the exhaust port of the engine and the secondary air valve to allow air to pass through (see, for example, Patent Document 2).

[0005] In this secondary air supply system, as in the case described above, the secondary air valve and the air cleaner are connected by a dedicated pipe (secondary air intake hose), which requires dedicated piping space, reducing layout freedom, increasing the number of parts and costs, and making it difficult to consolidate the installed parts.In addition, the operating sound of the solenoid valve is a concern as it creates noise. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-180812 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-59923 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in consideration of the above circumstances, and its object is to provide a secondary air supply system that can reduce the number of parts, reduce costs, increase layout freedom, reduce noise, etc. [Means for solving the problem]

[0008] The secondary air supply system of the present invention is a secondary air supply system for an engine that supplies air in an air cleaner to an exhaust passage via an internal passage of an opening / closing valve having a drive unit, wherein the air cleaner includes a through hole that penetrates its wall, and the opening / closing valve is fixed to the wall in the area of ​​the through hole so that at least the drive unit and the upstream opening end of the internal passage face inside the air cleaner and the downstream opening end of the internal passage faces outside the air cleaner.

[0009] In the secondary air supply system, an upstream open end of the internal passage may be provided vertically above a bottom surface of the air cleaner.

[0010] In the secondary air supply system, an upstream open end of the internal passage may be arranged at a position spaced inward from the inner wall surface of the wall portion of the air cleaner.

[0011] In the secondary air supply system, an upstream open end of the internal passage may be arranged to face downward in the vertical direction.

[0012] The secondary air supply system may have a configuration including a pipe that connects the internal passage of the on-off valve with the exhaust passage.

[0013] In the above secondary air supply system, the on-off valve may include a drive unit, a valve body driven by the drive unit to open and close the internal passage, and a main body that defines the internal passage, a fixed unit fixed to the wall portion, and a pipe portion to which piping is connected, and the on-off valve may have a configuration in which the fixed unit is fixed to the wall portion of the air cleaner with the pipe portion exposed to the outside of the air cleaner.

[0014] In the above secondary air supply system, the air cleaner may include a joint surface formed on the outer wall surface of the wall portion around the through hole and to which the fixing portion is joined, and a sealing member may be arranged between the fixing portion and the joint surface.

[0015] In the secondary air supply system, the main body may include a fitting portion that is adjacent to the fixing portion and that is fitted into the through-hole.

[0016] In the above secondary air supply system, a configuration may be adopted in which the air cleaner includes a female threaded hole in the area of ​​the joint surface, the main body includes a circular hole in the fixing portion through which a screw is passed to be screwed into the female threaded hole, and the opening / closing valve is fixed to the air cleaner by passing a screw through the circular hole and screwing it into the female threaded hole.

[0017] In the above secondary air supply system, the main body may have a circular hole in the fixing portion through which a tapping screw passes, and the opening / closing valve may be fixed to the air cleaner by passing the tapping screw through the circular hole and screwing it into the area of ​​the joint surface of the air cleaner.

[0018] In the above secondary air supply system, the drive unit may be an electromagnetic actuator including a solenoid, and the valve body may be directly connected to a movable part of the electromagnetic actuator.

[0019] In the above secondary air supply system, a configuration may be adopted in which the drive unit is an electromagnetic actuator including a solenoid, the valve body is directly connected to a movable part of the electromagnetic actuator, the main body includes a connector that electrically connects a coil included in the electromagnetic actuator, and the connector is arranged in an exposed state outside the air cleaner.

[0020] In the above secondary air supply system, a configuration may be adopted in which the drive unit is an electromagnetic actuator including a solenoid, the valve body is directly connected to a movable part of the electromagnetic actuator, the main body includes a connector that electrically connects a coil included in the electromagnetic actuator, and the connector is formed so as to extend parallel to the pipe portion in the same direction while being exposed to the outside of the air cleaner.

[0021] In the above secondary air supply system, a configuration may be adopted in which the drive unit is an electromagnetic actuator including a solenoid and a movable unit that reciprocates linearly around a predetermined axis, the valve body is directly connected to the movable unit, the main body includes a connector that electrically connects a coil included in the electromagnetic actuator and is arranged in an exposed state outside the air cleaner, and the pipe unit and the connector are formed to extend parallel to the reciprocating direction of the movable unit.

[0022] In the above secondary air supply system, the fixing portion may be a disk-shaped flange, and the pipe portion and the connector may be formed so as to extend in the same direction from an outer surface of the flange.

[0023] In the above secondary air supply system, a configuration may be adopted in which the pipe portion is formed so as to extend coaxially with the axis along which the movable portion reciprocates.

[0024] In the above secondary air supply system, the valve body may be configured to open the internal passage when the electromagnetic actuator is in a non-energized state.

[0025] In the secondary air supply system, a check valve for preventing backflow of air may be disposed between the pipe and the exhaust passage.

[0026] In the secondary air supply system, the air cleaner may include a filter member disposed therein, and an upstream opening end of the internal passage may face a region downstream of the filter member. [Effects of the Invention]

[0027] The secondary air supply system having the above configuration can achieve a reduction in the number of parts, a reduction in costs, an increase in the degree of freedom in layout, a reduction in noise, and the like. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a system diagram showing an intake and exhaust system of a motorcycle equipped with a secondary air supply system according to the present invention. [Figure 2] 1 is an external perspective view showing an air cleaner, an on-off valve, and piping in a secondary air supply system according to a first embodiment of the present invention. [Figure 3] 1 is an exploded perspective view showing an air cleaner, an on-off valve, and piping in a secondary air supply system according to a first embodiment of the present invention. FIG. [Figure 4] 1 is a partial cross-sectional view showing an air cleaner, an on-off valve, and piping in a secondary air supply system according to a first embodiment of the present invention. [Figure 5]1 is a partial cross-sectional view showing an air cleaner, an on-off valve, and piping in a secondary air supply system according to a first embodiment of the present invention. [Figure 6] 1 is an external perspective view showing an on-off valve included in a secondary air supply system according to a first embodiment of the present invention. [Figure 7] 1 is a side view showing an on-off valve included in a secondary air supply system according to a first embodiment of the present invention. [Figure 8] 1 is a cross-sectional view showing an on-off valve included in a secondary air supply system according to a first embodiment of the present invention. [Figure 9] 1 is a plan view of an on-off valve included in a secondary air supply system according to a first embodiment of the present invention, viewed from an axial direction. [Figure 10] 1 is a perspective view showing a drive unit and a valve body that form part of an on-off valve included in a secondary air supply system according to a first embodiment of the present invention. FIG. [Figure 11] FIG. 6 is a partial cross-sectional view showing an air cleaner, an on-off valve, and piping in a secondary air supply system according to a second embodiment of the present invention. [Figure 12] FIG. 10 is an exploded perspective view showing an air cleaner, an on-off valve, and piping in a secondary air supply system according to a third embodiment of the present invention. [Figure 13] FIG. 10 is a plan view of an on-off valve included in a secondary air supply system according to a third embodiment of the present invention, viewed from the axial direction. [Figure 14] FIG. 10 is a side view showing an on-off valve included in a secondary air supply system according to a third embodiment of the present invention. [Figure 15] FIG. 10 is a perspective cross-sectional view showing an on-off valve included in a secondary air supply system according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, the intake and exhaust system of an engine equipped with a secondary air supply system according to the present invention includes an engine body 1, an intake manifold 2, a throttle device 3, an intake duct 4, an outside air introduction duct 5, an exhaust manifold 6, an exhaust pipe 7, an air cleaner 10, an on-off valve V1 fixed directly to the air cleaner 10, a pipe P, and a check valve RV. As shown in FIGS. 2 to 5, the secondary air supply system according to the first embodiment is made up of an air cleaner 10, an on-off valve V1, a pipe P, and a check valve RV.

[0030] The engine body 1 includes a cylinder block CB and a cylinder head CH, and is equipped with a piston 1a, an intake valve 1b, an exhaust valve 1c, an ignition plug 1d, a pipe section 1e, a drive system (not shown) for the piston 1a, and drive systems for the intake valve 1b and the exhaust valve 1c. The engine body 1 also includes an exhaust port Ep in the cylinder head CH downstream of the exhaust valve 1c, which forms part of an exhaust passage, and a communication passage Cp that leads from the pipe section 1e to the exhaust port Ep and has a check valve RV disposed midway. The intake manifold 2 includes a surge tank and a plurality of branch pipes, each of which includes a fuel injection valve 2a. The throttle device 3 is connected to a surge tank of the intake manifold 2 and includes a butterfly valve that opens and closes the intake passage. The intake duct 4 is connected between the throttle device 3 and the air cleaner 10 to define an intake passage for introducing the intake air that has passed through the air cleaner 10 . The outside air intake duct 5 is connected to the connection portion 12b of the air cleaner 10 and guides the outside air into the air cleaner 10. The exhaust manifold 6 is connected between the engine body 1 and an exhaust pipe 7, and defines an exhaust passage through which exhaust gas discharged from an exhaust port Ep of the engine body 1 passes. The exhaust pipe 7 is connected to the exhaust manifold 6 to define an exhaust passage, and is provided with a catalyst 7a in the middle thereof.

[0031] 2 to 5, the air cleaner 10 includes a case body 11, a case cover 12 that covers the case body 11, and a filter member 13 housed in the internal space. Here, the case body 11 and the case cover 12 are molded from a resin material.

[0032] The case body 11 includes a connecting flange portion 11a that connects the case cover 12, a holding portion 11b that holds the filter member 13, a bottom wall portion 11c, a side wall portion 11d, a through hole 11e that penetrates the side wall portion 11d, a joint surface 11f formed on the outer wall surface of the side wall portion 11d, four female screw holes 11g formed in the area of ​​the joint surface 11f, and a connecting portion 11h (see Figure 1) that connects the upstream end of the intake duct 4.

[0033] The through-hole 11e is formed in the shape of a keyhole penetrating the side wall portion 11d so that the outer contour of the surrounding portion 25 surrounding the drive portion 50 of the on-off valve V1 can be inserted without contact. Here, the through-hole 11e is formed so that, with the on-off valve V1 fixed, the upstream opening end 21u of the internal passage 21 is located higher than the bottom wall portion 11c in the vertical direction Vd, i.e., higher than the bottom surface 11c1 of the air cleaner 10.

[0034] The joining surface 11f is formed on the outer wall surface of the side wall portion 11d around the through hole 11e so that the fixing portion 22 of the on-off valve V1 is joined thereto. The four female screw holes 11g are formed in the region of the joining surface 11f at positions corresponding to the circular holes 22a formed in the fixing portion 22 of the on-off valve V1.

[0035] The case cover 12 includes a connecting flange portion 12a that is connected to the connecting flange portion 11a of the case body 11, and a connecting portion 12b that connects the downstream end of the outside air intake duct 5 (see FIG. 1). The filter member 13 is held by the holding portion 11b of the case body 11 and housed in the internal space, and serves to filter dust and the like from the air introduced from the outside air introduction duct 5. The air filtered by the filter member 13 is supplied to the intake duct 4 and the on-off valve V1.

[0036] As shown in FIGS. 2 to 10, the on-off valve V1 includes a main body 20, a valve element 30 that reciprocates in the direction of an axis S, a biasing spring 40, and a drive unit 50. The main body 20 is molded from a resin material, has an elongated shape in the direction of the axis S, and includes an internal passage 21, a fixing portion 22, a pipe portion 24, an enclosing portion 25, and a connector .

[0037] The internal passage 21 is a passage through which air passes within the air cleaner 10, and is bent in an L shape to include an intermediate passage that extends in the direction of the axis S and accommodates the biasing spring 40, an upstream passage that extends perpendicular to the axis S, and a downstream passage that extends in the direction of the axis S within the pipe section 24. The internal passage 21 also includes a seating surface 21a on which the valve element 30 seats in the direction of the axis S to close the valve, a receiving surface 21b that receives one end 41 of the biasing spring 40 in the direction of the axis S, a stopper 21c that stops the valve element 30 in the fully open position, an upstream opening end 21u, and a downstream opening end 21d. The stopper 21c is made up of a plurality of protrusions that are discretely arranged in an annular shape, and when the valve body 30 is in contact with the protrusions, air flows through the spaces between the protrusions.

[0038] The fixing portion 22 is an area that is joined and fixed to the joining surface 11f of the air cleaner 10, and is formed as an approximately circular flange centered on the axis S and perpendicular to the axis S, specifically as a flange having an outer contour with part of the circular plate protruding radially. Here, the fixing portion 22 has four circular holes 22a arranged at equal intervals in the circumferential direction and through which the screws B are passed, and an annular groove 22b on its inner surface (the surface facing the joining surface 11f) into which the annular sealing member Sr is fitted. The fixing portion 22 is joined and fixed to the joining surface 11f of the air cleaner 10 with the seal member Sr fitted in the annular groove 22b.

[0039] The pipe portion 24 extends from the outer surface of the flange serving as the fixed portion 22 coaxially with the axis S about which the movable element 55 of the drive portion 50 and the valve element 30 reciprocate, and is formed in a cylindrical shape that defines a part of the internal passage 21. A piping P is connected to the pipe portion 24. The surrounding portion 25 is an area that houses the drive unit 50, and is molded during resin molding so as to embed and surround the stator (first yoke 53 and second yoke 54), bobbin 51, and coil 52 of the drive unit 50. The connector 26 is formed to extend parallel to the axis S, i.e., in the same direction as the pipe portion 24, from the outer surface of the flange serving as the fixed portion 22 so as to expose and surround the terminal 52b connected to the coil 52 of the drive portion 50 in order to electrically connect to the outside.

[0040] Here, the pipe portion 24 is formed to extend coaxially with the axis S about which the movable element 55 linearly reciprocates, so that the components can be concentrated closer to the axis S, thereby achieving a reduction in the diameter of the on-off valve V1. Moreover, the connector 26 is formed to extend in the same direction as the pipe portion 24, so that it similarly contributes to a reduction in the diameter of the on-off valve V1 and also makes it easy to attach the on-off valve V1 to the air cleaner 10, attach the piping P to the pipe portion 24, and connect an external connector to the connector 26.

[0041] As shown in Figures 4 and 10, the valve body 30 has a metal reinforcing plate 31 and a rubber part 32 molded to embed the reinforcing plate 31, and is formed in a circular plate shape and directly connected to the movable element 55 of the drive part 50. The rubber portion 32 includes an annular seal portion 32 a that seats on a seating surface 21 a of the internal passage 21 to close the internal passage 21 , and a receiving surface 32 b that receives the other end 42 of the biasing spring 40 .

[0042] The biasing spring 40 is a coil-type compression spring, and as shown in Figure 4, is arranged in an intermediate passage of the internal passage 21 that extends in the direction of the axis S, with one end 41 abutting against the receiving surface 21b and the other end 42 abutting against the receiving surface 32b of the valve body 30, biasing the valve body 30 in the valve-opening direction.

[0043] As shown in Figures 4 and 10, the drive unit 50 is a solenoid-type electromagnetic actuator, and includes a bobbin 51, an excitation coil 52, lead wires 52a, terminals 52b, a first yoke 53 and a second yoke 54 as stators, and a mover 55 that reciprocates in the direction of the axis S.

[0044] The bobbin 51 is molded using a resin material and includes a cylindrical portion 51a that guides the mover 55 in the direction of the axis S, a flange portion 51b on one end side, and a flange portion 51c near the other end side. The coil 52 is wound around the cylindrical portion 51a of the bobbin 51, and a metal terminal 52b is connected to the end of the coil 52 via a lead wire 52a. The terminal 52b is formed so that a part of it is embedded in the fixed portion 22 and the tip side is exposed inside the connector 26.

[0045] The first yoke 53 is made of a magnetic material and includes a bottomed cylindrical portion 53a fitted into the cylindrical portion 51a from the flange portion 51b side of the bobbin 51, and a flat portion 53b to which the second yoke 54 is connected. The second yoke 54 is made of a magnetic material and is bent into an approximately U-shape, and includes a flat portion 54a having a fitting hole 54a1 that fits into the cylindrical portion 51a from the flange portion 51c side of the bobbin 51, and an arm portion 54b that extends from the flat portion 54a outside the coil 52 in the direction of the axis S and to which the first yoke 53 is connected. The mover 55 is made of a magnetic material and includes a bottomed cylindrical portion 55a disposed within the cylindrical portion 51a, and a rod portion 55b extending from the bottomed cylindrical portion 55a in the direction of the axis S and connecting the valve body 30 at its tip.

[0046] The on-off valve V1 having the above-described configuration is set so that when the coil 52 is not energized, the internal passage 21 is opened by the biasing force of the biasing spring 40, and when the coil 52 is energized, the annular seal portion 32a of the valve body 30 seats on the seating surface 21a against the biasing force of the biasing spring 40, thereby closing the internal passage 21.

[0047] The pipe P is a rubber hose made of a rubber material or the like, and its upstream end is connected to the pipe portion 24 of the on-off valve V1, and its downstream end is connected to the pipe portion 1e of the cylinder head CH. That is, the pipe P connects the internal passage 21 of the on-off valve V1 to the exhaust port Ep of the cylinder head CH, which forms part of the exhaust passage, via the communication passage Cp of the cylinder head CH.

[0048] The check valve RV is a cantilever-shaped reed valve located midway in the connecting passage Cp of the cylinder head CH. It is closed when the engine body 1 is stopped, and bends and opens when the engine body 1 starts and the negative pressure in the exhaust passage exceeds a predetermined level.

[0049] The installation work of the on-off valve V1 having the above configuration is completed by fitting the sealing member Sr into the annular groove 22b of the fixing portion 22, inserting the surrounding portion 25 surrounding the drive portion 50 of the main body 20 of the on-off valve V1 into the air cleaner 10 through the through hole 11e so that the area of ​​the surrounding portion 25 facing the inside of the air cleaner 10 faces the inside of the air cleaner 10, joining the fixing portion 22 to the joining surface 11f, and then inserting the screw B into the circular hole 22a and screwing it into the female threaded hole 11g. As a result, the on-off valve V1 is fixed so as to face an area downstream of the filter member 13 arranged inside the air cleaner 10. Then, the air inside the air cleaner 10, from which dust and the like has been filtered by the filter member 13, flows directly from the upstream opening end 21u into the internal passage 21. That is, the on-off valve V1 is arranged in the area of ​​the through-hole 11e so that the drive unit 50 and the upstream opening end 21u of the internal passage 21 face inside the air cleaner 10, and the downstream opening end 21d of the internal passage 21 faces outside the air cleaner 10.

[0050] In the secondary air supply system of the first embodiment having the above-described configuration, after the engine body 1 starts, the check valve RV opens in response to the negative pressure in the exhaust passage (exhaust port Ep), and the air in the air cleaner 10 is supplied to the exhaust passage (exhaust port Ep) through the internal passage 21 of the opening / closing valve V1, the passage of the piping P, and the connecting passage Cp of the cylinder head CH. This allows unburned HC and CO to be re-burned, reducing the amount of HC and CO that is emitted. On the other hand, when the throttle (accelerator) is suddenly released to decelerate, the coil 52 is energized and the on-off valve V1 closes the internal passage 21 in order to prevent self-ignition (afterfire) from occurring when the unburned gas is concentrated in the exhaust passage.

[0051] According to the secondary air supply system of the first embodiment, the on-off valve V1 is disposed in the area of ​​the through-hole 11e so that the drive unit 50 and the upstream opening end 21u of the internal passage 21 face the inside of the air cleaner 10 and the downstream opening end 21d of the internal passage 21 faces the outside of the air cleaner 10, and is fixed to the wall (the joint surface 11f of the side wall 11d). This eliminates the need for piping connecting the air cleaner and the on-off valve as in the prior art, thereby reducing the number of parts and costs, and increasing the freedom of layout due to the increased free space. Furthermore, because the drive unit 50, which generates noise such as operating sounds, is housed inside the air cleaner 10, noise can be reduced.

[0052] Furthermore, the upstream opening end 21u of the internal passage 21, which serves as the air inlet, is located above the bottom surface 11c1 of the air cleaner 10 in the vertical direction Vd, so that even if water droplets generated by condensation or the like in the internal space of the air cleaner 10 accumulate on the bottom surface 11c1, the water droplets can be prevented from flowing into the internal passage 21 of the opening / closing valve V1. In particular, the upstream opening end 21u of the internal passage 21 is positioned at a distance inward from the inner wall surface of the side wall portion 11d, which serves as a wall portion, and therefore water droplets and the like adhering to the inner wall surface of the side wall portion 11d can be prevented from entering the internal passage 21 from the upstream opening end 21u when flowing down toward the bottom surface 11c1. Furthermore, since the upstream open end 21u of the internal passage 21 is arranged to face downward in the vertical direction Vd, it is possible to reliably prevent water droplets and the like from entering.

[0053] Furthermore, when attaching the on-off valve V1 to the air cleaner 10, the area of ​​the surrounding portion 25 surrounding the drive portion 50 of the main body 20 is inserted into the through hole 11e, the fixing portion 22 is joined to the joining surface 11f, and the screw B is passed through the circular hole 22a and screwed into the female screw hole 11g, thereby making it possible to easily perform the installation work (fixing work). Furthermore, since the pipe portion 24 and the connector 26 extend parallel in the same direction from the outer surface of the fixing portion 22 (flange) while being exposed to the outside of the air cleaner 10, the installation work of the piping P and the connection work of the external connector can be easily performed.

[0054] FIG. 11 shows a secondary air supply system according to a second embodiment of the present invention, and the same components as those in the first embodiment are given the same reference numerals and will not be described. The secondary air supply system according to the second embodiment is made up of an air cleaner 100, an on-off valve V1, a pipe P, and a check valve RV.

[0055] 11, the air cleaner 100 includes a case body 101, a case cover 12 that covers the case body 101, and a filter member 13 housed in the internal space. Here, the case body 101 and the case cover 12 are molded from a resin material.

[0056] The case body 101 includes a connecting flange portion 11a, a holding portion 11b, a bottom wall portion 11c, a side wall portion 11d, a through hole 101e penetrating the bottom wall portion 11c, a joint surface 101f formed on the outer wall surface of the bottom wall portion 11c, four female screw holes 101g formed in the area of ​​the joint surface 101f, and a connection portion 11h (see Figure 1).

[0057] The through-hole 101e is formed in the shape of a keyhole penetrating the bottom wall portion 11c so that the outer contour of the surrounding portion 25 surrounding the drive portion 50 of the on-off valve V1 can be inserted without contact. The joining surface 101f is formed on the outer wall surface of the bottom wall portion 11c around the through hole 101e so that the fixing portion 22 of the on-off valve V1 is joined thereto. The four female screw holes 101g are formed in the region of the joining surface 101f at positions corresponding to the circular holes 22a formed in the fixing portion 22 of the on-off valve V1.

[0058] In the above configuration, the installation work of the on-off valve V1 is completed by fitting the sealing member Sr into the annular groove 22b of the fixing portion 22, inserting the surrounding portion 25 surrounding the drive portion 50 of the main body 20 of the on-off valve V1 into the air cleaner 100 through the through hole 101e so that the area of ​​the surrounding portion 25 facing the inside of the air cleaner 100 faces the inside of the air cleaner 100, joining the fixing portion 22 to the joining surface 101f, and then inserting the screw B into the circular hole 22a and screwing it into the female threaded hole 101g. As a result, the on-off valve V1 is fixed so as to face an area downstream of the filter member 13 arranged inside the air cleaner 100. Then, the air inside the air cleaner 100, from which dust and the like have been filtered by the filter member 13, flows directly into the internal passage 21 from the upstream opening end 21u.

[0059] According to the secondary air supply system of the second embodiment, the on-off valve V1 is disposed in the area of ​​the through-hole 101e so that the drive unit 50 and the upstream opening end 21u of the internal passage 21 face inside the air cleaner 100 and the downstream opening end 21d of the internal passage 21 faces outside the air cleaner 100, and is fixed to the wall (the joint surface 101f of the bottom wall 11c). This eliminates the need for piping connecting the air cleaner and the on-off valve as in the prior art, thereby reducing the number of parts and costs, and increasing the freedom of layout due to the increased free space. Furthermore, since the drive unit 50, which generates noise such as operating sounds, is housed inside the air cleaner 100, noise can be reduced.

[0060] Furthermore, the upstream opening end 21u of the internal passage 21, which serves as the air inlet, is located above the bottom surface 11c1 of the air cleaner 100 in the vertical direction Vd, so that even if water droplets generated by condensation or the like in the internal space of the air cleaner 100 accumulate on the bottom surface 11c1, the water droplets can be prevented from flowing into the internal passage 21 of the on-off valve V1. In particular, the upstream opening end 21u of the internal passage 21 is positioned at a distance inward from the inner wall surfaces of the wall portions (bottom wall portion 11c and side wall portion 11d), and therefore, it is possible to prevent water droplets and the like adhering to the inner wall surface of side wall portion 11d from entering the internal passage 21 from the upstream opening end 21u when flowing down toward the bottom surface 11c1.

[0061] Furthermore, when attaching the on-off valve V1 to the air cleaner 100, the area of ​​the surrounding portion 25 surrounding the drive portion 50 of the main body 20 is inserted into the through hole 11e, the fixing portion 22 is joined to the joining surface 11f, and the screw B is passed through the circular hole 22a and screwed into the female screw hole 11g, thereby making it possible to easily perform the installation work (fixing work). Furthermore, since the pipe portion 24 and the connector 26 extend parallel in the same direction from the outer surface of the fixing portion 22 (flange) while being exposed to the outside of the air cleaner 100, the installation work of the piping P and the connection work of the external connector can be easily performed.

[0062] 12 to 15 show a secondary air supply system according to a third embodiment of the present invention, and the same components as those in the first embodiment are given the same reference numerals and descriptions thereof will be omitted. The secondary air supply system according to the third embodiment is composed of an air cleaner 200, an on-off valve V2, a pipe P, and a check valve RV.

[0063] The air cleaner 200 includes a case body 201, a case cover 12 that covers the case body 201, and a filter member 13 housed in the internal space. Here, the case body 201 and the case cover 12 are molded from a resin material.

[0064] The case body 201 includes a connecting flange portion 11a, a holding portion 11b, a bottom wall portion 11c, a side wall portion 11d, a through hole 201e relating to the side wall portion 11d, a joint surface 201f formed on the outer wall surface of the side wall portion 11d, four female screw holes 201g formed in the area of ​​the joint surface 201f, and a connection portion 11h (see Figure 1).

[0065] The through-hole 201e is formed as a cylindrical hole into which the outer contour of the surrounding portion 25 that surrounds the drive portion 50 of the on-off valve V2 is inserted without contact and into which the fitting portion 127 of the on-off valve V2 is fitted. Here, the through-hole 201e is formed so that, with the on-off valve V2 fixed, the upstream opening end 21u of the internal passage 21 is located higher in the vertical direction Vd than the bottom wall portion 11c, i.e., above the bottom surface 11c1 of the air cleaner 200.

[0066] The on-off valve V2 includes a main body 120, a valve element 30 that reciprocates in the direction of an axis S, a biasing spring 40, and a drive unit 150. The main body 120 is molded from a resin material, has an elongated shape in the direction of the axis S, and includes an internal passage 21, a fixing portion 122, a pipe portion 24, an enclosing portion 25, a connector 26, and a fitting portion 127.

[0067] The fixing portion 122 is an area that is joined and fixed to the joining surface 201f of the air cleaner 200, and is formed as an approximately circular flange centered on the axis S and perpendicular to the axis S, specifically as a flange having an outer contour with part of the circular plate protruding radially. Here, the fixing portion 122 has four circular holes 122a that are arranged at equal intervals in the circumferential direction and through which the screws B are passed. The fixing portion 122 is joined to and fixed to the joining surface 201f of the air cleaner 200. The fitting portion 127 is adjacent to the fixed portion 122, is centered on the axis S, and is formed in a cylindrical shape with a smaller diameter than the fixed portion 122, and is formed to fit into the through-hole 201e of the air cleaner 200. The fitting portion 127 also has an annular groove 127a on its outer periphery into which the seal member Sr2 is fitted.

[0068] The drive unit 150 is a solenoid-type electromagnetic actuator and includes a bobbin 51, an excitation coil 52, lead wires 152a, terminals 152b, a first yoke 53 and a second yoke 54 as stators, and a mover 55 that reciprocates in the direction of the axis S. The coil 52 is wound around the cylindrical portion 51a of the bobbin 51, and a metal terminal 152b is connected to the end of the coil 52 via a lead wire 152a. The terminal 152b is formed so that a portion thereof is embedded in the fixed portion 122 and the fitting portion 127, and the tip side thereof is exposed inside the connector 26.

[0069] In the above configuration, the installation work of the on-off valve V2 is completed by fitting the sealing member Sr2 into the annular groove 127a of the fitting portion 127, inserting the area of ​​the surrounding portion 25 surrounding the drive unit 150 of the main body 120 of the on-off valve V2 into the air cleaner 200 through the through hole 201e so that it faces the inside of the air cleaner 200, fitting the fitting portion 127 into the through hole 201e, joining the fixing portion 122 to the joining surface 201f, and then inserting the screw B into the circular hole 122a and screwing it into the female screw hole 201g. As a result, the on-off valve V2 is fixed so as to face an area downstream of the filter member 13 arranged inside the air cleaner 200. Then, the air inside the air cleaner 200, from which dust and the like have been filtered by the filter member 13, flows directly into the internal passage 21 from the upstream opening end 21u.

[0070] According to the secondary air supply system of the third embodiment, the on-off valve V2 can be easily installed while being positioned at a predetermined position because the fitting portion 127 is fitted into the through-hole 201e. Furthermore, in the area of ​​the through-hole 201e, the drive unit 150 and the upstream opening end 21u of the internal passage 21 face the inside of the air cleaner 200, and the downstream opening end 21d of the internal passage 21 faces the outside of the air cleaner 200. The drive unit 150 is fixed to the wall (the joint surface 201f of the side wall 11d). This eliminates the need for piping connecting the air cleaner and the on-off valve, as in the prior art. This reduces the number of parts and costs, and increases the layout flexibility due to the increased free space. Furthermore, since the drive unit 50, which generates noise such as operating sounds, is housed inside the air cleaner 200, noise can be reduced.

[0071] Furthermore, the upstream opening end 21u of the internal passage 21, which serves as the air inlet, is located above the bottom surface 11c1 of the air cleaner 200 in the vertical direction Vd, so that even if water droplets generated by condensation or the like in the internal space of the air cleaner 200 accumulate on the bottom surface 11c1, the water droplets can be prevented from flowing into the internal passage 21 of the opening / closing valve V3. In particular, the upstream opening end 21u of the internal passage 21 is positioned at a distance inward from the inner wall surface of the wall portion (side wall portion 11d), thereby preventing water droplets and the like adhering to the inner wall surface of the side wall portion 11d from entering the internal passage 21 from the upstream opening end 21u when flowing down toward the bottom surface 11c1.

[0072] In the above embodiment, a solenoid-type electromagnetic actuator having a movable element 55 that reciprocates in the direction of the axis S is shown as the driving unit included in the on-off valves V1 and V2, but this is not limited to this, and an on-off valve having a rotary drive source as the driving unit or any other type of on-off valve may be used as long as it is an on-off valve that can open and close the internal passage 21 on and off.

[0073] In the above embodiment, the on-off valves V1 and V2 are fixed to the wall portions of the air cleaners 10, 100 and 200 by joining the fixing portions 22 and 122 to the outer wall surfaces of the wall portions (side wall portion 11d and bottom wall portion 11c), but this is not limited to this, and a fixing configuration in which the fixing portions are joined to the inner wall surfaces of the wall portions of the air cleaner may also be adopted. In this case, the on-off valve is disposed so that all parts thereof, except for the pipe portion and the connector, face the inside of the air cleaner. The on-off valve is attached by inserting it into the case body and joining it from the inside, with the case cover and filter member removed. In this configuration, the air cleaner and on-off valve can be handled as an integrated module.

[0074] In the above embodiment, in the on-off valves V1 and V2, the pipe section 24 and the connector 26 extend in the same direction on the same side, but this is not limited to this, and a form in which they extend in a desired direction may be adopted depending on the required wiring layout.

[0075] In the above embodiment, the method of fixing the on-off valves V1, V2 to the air cleaners 10, 100, 200 is such that the air cleaners 10, 100, 200 include pre-formed female threaded holes 11g, 101g, 201g in the area of ​​the joining surfaces 11f, 101f, 201f, the main bodies 20, 120 of the on-off valves V1, V2 include circular holes 22a, 122a in the fixing portions 22, 122 through which screws B are passed to be screwed into the female threaded holes 11f, 101f, 201f, and the on-off valves V1, V2 are fixed to the air cleaners 10, 100, 200 by passing the screws B through the circular holes 22a, 122a and screwing them into the female threaded holes 11g, 101g, 201g, but this is not limited to this. For example, a structure may be adopted in which the main body of the on-off valve includes a circular hole at the fixing portion through which a tapping screw (also called a tapping screw or tap screw) passes, the air cleaner has an area in the area of ​​the joint surface into which the tapping screw is screwed, and the on-off valve is fixed to the air cleaner by passing the tapping screw through the circular hole and screwing it into the area of ​​the joint surface of the air cleaner. In addition, a protruding mating pin may be provided on the air cleaner and a ring-shaped elastic member (grommet) may be provided on the opening / closing valve, and a soft-mount mating structure may be adopted. Alternatively, any other method may be adopted as long as it allows the opening / closing valve to be directly fixed to the air cleaner.

[0076] In the above embodiment, a configuration has been shown in which the check valve RV included in the secondary air supply system is arranged midway through the communicating passage Cp formed in the cylinder head CH to supply air to the exhaust port Ep, but this is not limited to this, and as long as required conditions are met, a configuration in which the check valve RV is arranged midway through the passage member leading from the piping P to the exhaust pipe 7 to supply air to the exhaust pipe 7 further downstream may also be adopted.

[0077] As described above, the secondary air supply system of the present invention can achieve a reduction in the number of parts, lower costs, increased freedom in layout, and reduced noise, and is therefore useful not only for motorcycles and the like, but also for other vehicles. [Explanation of symbols]

[0078] 1 Engine body CB cylinder block CH cylinder head Ep exhaust port (exhaust passage) Cp communication path 1a Piston 1b Intake valve 1c Exhaust valve 1d Spark plug 1e Pipe section 2 intake manifolds 2a Fuel injection valve 3 Throttle device 4. Intake duct 5. Outside air intake duct 6 exhaust manifold 7 exhaust pipe 7a catalyst Vd vertical direction 10 Air cleaner 11 Case body 11c Bottom wall (wall) 11c1 bottom 11d Side wall (wall) 11e Passageway 11f Joint surface (exterior wall surface) 11g female screw hole 12 Case cover 13 Filter material P piping RV check valve B screw V1 On-off valve 20 Main Unit 21 Internal passage 21u upstream opening end 21d Downstream opening end 22 Fixed part 22a circular hole Sr sealing material 24 Pipe section 25 Surrounding area 26 Connectors 30 Valve body 40 bias spring 50 Drive unit (solenoid type electromagnetic actuator) 51 Bobbin 52 Coil 52a lead wire 52b terminal 53 First York 54 Second York 55 Mover 100 air cleaner 101 Case body 101e Through hole 101f Joint surface 101g female screw hole V2 shut-off valve 120 body 122 Fixed part 122a circular hole 127 Fitting part 127a Annular groove Sr2 sealing material 150 Drive unit 152a lead wire 152b terminal 200 air cleaner 201 Case body 201e Through hole 201f Joint surface 201g female screw hole

Claims

1. A secondary air supply system for an engine that supplies air in an air cleaner to an exhaust passage through an internal passage of an on-off valve having a drive unit, The air cleaner includes a through hole penetrating a wall portion thereof, the on-off valve is disposed in the region of the through hole such that at least the drive portion and an upstream opening end of the internal passage face the inside of the air cleaner, and a downstream opening end of the internal passage faces the outside of the air cleaner, and is fixed to the wall portion. A secondary air supply system.

2. an upstream opening end of the internal passage is provided above a bottom surface of the air cleaner in the vertical direction; 2. The secondary air supply system according to claim 1.

3. The upstream opening end is disposed at a position spaced inward from the inner wall surface of the wall portion.

3. The secondary air supply system according to claim 2.

4. The upstream opening end is arranged to face downward in the vertical direction.

4. The secondary air supply system according to claim 3.

5. a pipe that connects the internal passage of the on-off valve with the exhaust passage; 2. The secondary air supply system according to claim 1.

6. the on-off valve includes the drive unit, a valve element driven by the drive unit to open and close the internal passage, and a main body that defines the internal passage, a fixed portion fixed to the wall portion, and a pipe portion to which the piping is connected, The on-off valve is fixed to a wall of the air cleaner at the fixing portion with the pipe portion exposed to the outside of the air cleaner.

6. A secondary air supply system according to claim 5.

7. the air cleaner includes a joining surface formed on an outer wall surface of the wall portion around the through hole, the joining surface being joined to the fixing portion, A seal member is disposed between the fixing portion and the joining surface.

7. A secondary air supply system according to claim 6.

8. The main body includes a fitting portion adjacent to the fixing portion and fitted into the through hole.

8. A secondary air supply system according to claim 7.

9. the air cleaner includes a female threaded hole in the area of ​​the interface; the main body includes a circular hole in the fixing portion through which a screw to be screwed into the female screw hole is passed, The on-off valve is fixed to the air cleaner by passing the screw through the circular hole and screwing it into the female screw hole.

8. A secondary air supply system according to claim 7.

10. the main body includes a circular hole in the fixing portion through which a tapping screw is inserted; The on-off valve is fixed to the air cleaner by passing the tapping screw through the circular hole and screwing it into the region of the joint surface of the air cleaner.

8. A secondary air supply system according to claim 7.

11. the driving unit is an electromagnetic actuator including a solenoid, The valve body is directly connected to a movable part of the electromagnetic actuator.

2. The secondary air supply system according to claim 1.

12. the driving unit is an electromagnetic actuator including a solenoid, the valve element is directly connected to a movable part of the electromagnetic actuator, the main body includes a connector that electrically connects a coil included in the electromagnetic actuator; The connector is disposed in an exposed state outside the air cleaner.

2. The secondary air supply system according to claim 1.

13. the driving unit is an electromagnetic actuator including a solenoid, the valve element is directly connected to a movable part of the electromagnetic actuator, the main body includes a connector that electrically connects a coil included in the electromagnetic actuator; The connector is formed so as to extend in parallel with the pipe portion in the same direction as the pipe portion while being exposed to the outside of the air cleaner.

7. A secondary air supply system according to claim 6.

14. the drive unit is an electromagnetic actuator including a solenoid and a movable unit that linearly reciprocates around a predetermined axis, The valve body is directly connected to the movable part, the main body includes a connector that electrically connects a coil included in the electromagnetic actuator and is disposed in an exposed state outside the air cleaner, The pipe portion and the connector are formed to extend parallel to the reciprocating direction of the movable portion.

7. A secondary air supply system according to claim 6.

15. The fixing portion is a disk-shaped flange, The pipe portion and the connector are formed to extend in the same direction from the outer surface of the flange.

15. The secondary air supply system according to claim 14.

16. The pipe portion is formed to extend coaxially with the axis line.

16. The secondary air supply system according to claim 15.

17. the valve body is configured to open the internal passage when the electromagnetic actuator is in a non-energized state.

10. The secondary air supply system according to claim 9.

18. A check valve is disposed between the piping and the exhaust passage to prevent backflow of air.

6. A secondary air supply system according to claim 5.

19. The air cleaner includes a filter member disposed therein. an upstream opening end of the internal passage faces a region downstream of the filter member; 19. A secondary air supply system according to any one of the preceding claims.

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