JP5932522B2 - Intake device for multi-cylinder engine - Google Patents

Description

  According to the present invention, one and the other throttle bodies joined in parallel to each other include an intake passage connected to intake ports of a plurality of cylinders of the engine, and a throttle valve for opening and closing each intake passage. The body is provided with a plurality of bypasses whose upstream ends open to the atmosphere or each intake passage upstream of each throttle valve, and whose other ends open to each intake passage downstream of each throttle valve. The present invention relates to an improvement of an intake device for a multi-cylinder engine provided with a bypass control valve for opening and closing the valve.

  The bypass control valve in the intake system for a multi-cylinder engine operates mainly to adjust the amount of fast idle air supplied to the engine through the bypass in order to properly control the fast idle speed when the engine is warming up. .

  Such an intake device for a multi-cylinder engine is already known as disclosed in Patent Document 1.

JP 2006-307730 A

  In such an intake device for a multi-cylinder engine disclosed in Patent Document 1, a bypass control valve is attached to one throttle body, and a bypass extending from the bypass control valve to the intake passage of the other throttle body is provided. Because a flexible communication pipe is used in the downstream part of the engine, when assembling the intake system, a complicated process is required to connect the communication pipe to the bypass control valve and the joint of the throttle body. In addition, during use, the communication pipe protrudes outward from the throttle body, so that not only the intake device becomes larger, but the communication pipe may interfere with other parts of the engine room. It also affects the peripheral component layout and restricts the degree of freedom of the component layout.

  The present invention has been made in view of such circumstances, and provides a compact multi-cylinder engine intake device that can form a bypass without using a communication pipe, has good assemblability, and is compact. With the goal.

In order to achieve the above object, the present invention provides an intake passage in which one and the other throttle bodies joined in parallel with each other are connected to intake ports of a plurality of cylinders of the engine, and a throttle valve for opening and closing each intake passage. The one and the other throttle bodies have a plurality of openings whose upstream ends open to the atmosphere or each intake passage upstream from each throttle valve and whose other ends open to each intake passage downstream from each throttle valve. In a multi-cylinder engine intake device, in which bypasses are provided and bypass control valves for opening and closing the bypasses are provided, the bypass control valve is disposed on one side of one throttle body along the arrangement direction of both throttle bodies. The first and second intake passages are arranged side by side on the other throttle body, and the two throttle bodies are placed on both sides of the intake passage. A first bypass downstream passage extending from the bypass control valve and reaching the first intake passage, and a second bypass passage extending from the bypass control valve and reaching the second intake passage. A second bypass downstream passage, and the first and second bypass downstream passages extend from the bypass control valve and pass through the wall of one throttle body and the other throttle body of one throttle body. A first through hole that opens the downstream end to the joint surface, and the other throttle body so as to pass through the wall of the other throttle body and communicate the upstream end with the downstream end of the first through hole, together to open the joint surface between one of the throttle body, constituted by a second through hole that opens the downstream end to the intake passage of the other throttle body, the first passage of the second bypass downstream passage Is formed so that it extends from the one side of one throttle body to the other side opposite to the throttle body and passes through the wall of the other side, and communicates with the first through hole. The first feature is that the second through hole of the two bypass downstream passage is formed so as to pass through the wall of the other throttle body on the same side as the one throttle body . The one throttle body and the other throttle body respectively correspond to a first throttle body 1A and a second throttle body 1B in an embodiment of the present invention described later.

According to the present invention, in addition to the first feature, the throttle body is arranged with the downstream side of each intake passage facing downward, and the arrangement of both throttle bodies in the first and second bypass downstream passages is provided. The second feature is that the portion extending in the direction is formed at the same height position close to the upper end of the throttle body in the vertical direction .

Furthermore, in addition to the first or second feature, the present invention provides a bypass downstream downstream passage extending from the bypass control valve to the intake passage of one throttle body, a part of which intakes one throttle body. A third feature is that one throttle body is formed so as to overlap a part of the first through hole in a plan view as viewed from the axial direction of the road .

Is found in or present invention, in addition to any one of the first to third aspect, in order to common and one of the throttle body and the other of the throttle body, the provided the same number of intake paths in the throttle bodies, the one The bypass control valve is attached to a control block joined to one side of the throttle body, and a part of a plurality of bypass downstream passages from the bypass control valve to all intake passages is formed. A fourth feature is that a part of the bypass downstream passage toward the other intake passage is formed in the passage forming member joined to one side surface of the throttle body.

Furthermore, in addition to any of the first to fourth features , the present invention forms an injection valve mounting boss for mounting a fuel injection valve on one side or the other side of each throttle body. A fifth feature is that the mounting boss is disposed on the downstream side of each of the first and second bypass downstream passages along the respective intake passages from the portion extending in the arrangement direction of both throttle bodies.

In addition to the fifth feature of the present invention, a portion of the first bypass downstream passage extending in the direction of arrangement of the two throttle bodies in the direction along the axis of the intake passage is a rear end of the fuel injection valve. And the upstream end portion of each throttle body along each intake passage.

  Furthermore, in addition to any of the first to sixth features, the present invention provides a space between the first through hole and the second through hole between the joint surfaces of one throttle body and the other throttle body. A seventh feature is that a seal member surrounding the communication portion is interposed.

  Furthermore, in addition to any of the first to seventh features, the present invention provides a space between the first through hole and the second through hole at an opposing portion between one throttle body and the other throttle body. The eighth feature is that communication is made through a tubular body fitted through a seal member.

  According to the first feature of the present invention, in order to connect one and the other throttle bodies, they are brought into contact with each other, so that they extend from a bypass control valve attached to one throttle body and the intake passage of the other throttle body. Therefore, a multi-cylinder engine intake device having a simple structure and good assemblability can be obtained. Further, since most of the bypass downstream passage is formed in the walls of both throttle bodies, there is almost no overhanging outward of both throttle bodies, which can contribute to the compactness of the multi-cylinder engine intake device.

In addition , the intermediate wall connecting one side and the other side of one throttle body is used to form the first through hole, improving space efficiency and making the intake system for multi-cylinder engines more compact. Can contribute.

Furthermore, the other throttle body is provided with first and second intake passages in parallel, a first bypass downstream passage extending from the bypass control valve and reaching the first intake passage, and extending from the bypass control valve. And the second bypass downstream passage reaching the second intake passage is formed in the walls of one throttle portion and the other lateral portion of the two throttle bodies facing each other across the intake passage. The bypass downstream passage can be divided into one side and the other side of both throttle bodies and can be formed in each side wall, ensuring the compactness of the intake system and facilitating interference between the bypass downstream passages. , Can be avoided reliably.

According to the third aspect of the present invention, while ensuring the compactness of one throttle body, it is easy to interfere with the bypass downstream passage of the bypass reaching the intake passage of the one throttle body and the first through hole, It can be avoided reliably .

According to the fourth aspect of the present invention, by simply removing the control block and the passage forming member, both throttle bodies can be made common, the mass productivity thereof can be improved, and the cost of the intake device for a multi-cylinder engine can be reduced. . Further, by forming a complicatedly bent portion of each bypass downstream passage in the control block and the passage forming member, it is possible to contribute to improvement of workability.

According to the fifth aspect of the present invention, the injection valve mounting boss and the portions of the first and second bypass downstream passages extending in the arrangement direction of both throttle bodies are formed on the same side portion of both throttle bodies. Nevertheless, mutual interference can be avoided.

  According to the seventh aspect of the present invention, the airtightness of the communication portion of the first through hole and the second through hole is ensured to reliably prevent intake air leakage from the communication portion, thereby improving the accuracy of the bypass intake control. be able to.

  According to the eighth aspect of the present invention, the pipes fitted between the first through hole and the second through hole, respectively, on the opposing portions of the one throttle body and the other throttle body via the seal member. Since the communication is performed through the body, even when there is a gap between the opposing portions of both throttle bodies, it is possible to ensure communication without air leakage between the first through hole and the second through hole.

1 is a front view of an intake device for a multi-cylinder engine according to an embodiment of the present invention. FIG. 2 is a plan view taken in the direction of arrow 2 in FIG. 1. FIG. 3 is a rear view taken in the direction of arrow 3 in FIG. 1. FIG. 4 is a partially exploded enlarged view of part 4 of FIG. 1. Partially exploded view of part 5 of FIG. FIG. 6 is a sectional view taken along line 6-6 in FIG. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 4. FIG. 9 is a sectional view taken along line 9-9 in FIG. 4. FIG. 10 is a sectional view taken along line 10-10 in FIG. 4; FIG. 11 is a sectional view taken along line 11-11 in FIG. 5; The whole intake passage system figure of the same intake device. The expanded sectional view of the junction part of the 1st and 2nd throttle body which shows the 2nd Embodiment of this invention.

1 to 3 and 12, reference numeral D denotes a four-cylinder engine intake device, which includes first and second throttle bodies 1A and 1B arranged in parallel. A plurality of pairs of connecting bosses 13a and 13b (only one pair is shown in FIG. 3) are integrally formed on the opposing surfaces of both the throttle bodies 1A and 1B, and these connecting bosses 13a and 13b are brought into contact with each other by connecting bolts 11. By joining, both throttle bodies 1A and 1B are integrally coupled as one throttle body assembly. These throttle bodies 1A, 1B are provided with a pair of intake passages 2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ parallel to each other. The first and second throttle bodies 1A, 1B are provided with intake passages 2 ₁ , 2 ₂ ; arranged in a downdraft type with the downstream side of 2 ₃ and 2 ₄ facing downward. The intake passages 2 ₁ and 2 ₂ of the first throttle body 1A have downstream ends connected to the intake ports E ₁ and E ₂ of the first and second cylinders of the engine, and the intake passages 2 ₃ and 2 of the second throttle body 1B. ₄ , the downstream end is connected to intake ports E ₃ and E ₄ of the third and fourth cylinders of the engine. An air cleaner 3 is attached to the upstream ends of the throttle bodies 1A and 1B. Each pair of intake passages 2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ is arranged symmetrically, and both throttle bodies 1A, 1B are basically configured to be able to be shared.

The first and second throttle bodies 1A, the 1B, each of the intake paths 2 _{1, 2} 2; 2 _3, 2 ₄ valve shaft 4, 4 across the is rotatably supported, each intake paths 2 _1, 2 _2; 2 _3, 2 ₄ throttle valve 5 ₁ for opening and closing the 5 _2; 5 _3, 5 ₄ are attached to each valve shaft 4,4. Both valve shafts 4 and 4 are coaxially arranged, and opposite ends thereof are connected to each other via a throttle drum 6. By rotating the throttle drum 6, all the throttle valves 5 ₁ are arranged. , 5 ₂ ; 5 ₃ , 5 ₄ can be opened and closed simultaneously. The throttle bodies 1A and 1B are connected to the intake ports E _{1 to} E of the engine through intake passages 2 ₁ , 2 ₂ ; 2 ₃ and 2 ₄ on the downstream side of the throttle valves 5 ₁ and 5 ₂ ; 5 ₃ and 5 _{4. 4} the fuel injection valve ₇₁ for injecting fuel into, 7 _2; 7 _3, 7 ₄ are mounted.

The first throttle body 1A has a single air inlet chamber 8 formed between the pair of intake passages 2 ₁ and 2 ₂ and opened at the upper end surface of the first throttle body 1A on the air cleaner 3 side, and the air inlet chamber. 8 is formed, and a bypass control valve 10 is connected to the guide passage 9. The air inlet chamber 8 and the guide passage 9 constitute a bypass upstream passage 12a.

From the bypass control valve 10, one pair of bypass downstream passages 12b ₁ , 12b ₂ ; 12b ₃
12b ₄ extends, and one set of bypass downstream passages 12b ₁ and 12b ₂ open to the intake passages 2 ₁ and 2 ₂ downstream of the throttle valves 5 ₁ and 5 _{2 of} the first throttle body 1A, respectively. , another set of bypass downstream passage 12b ₃ ～12B ₄ is the second throttle body 1B, respectively opening to the throttle valve _3, 5 ₄ downstream of the intake paths 2 _3, 2 _4.

Thus, as clearly shown in FIG. 12, the bypass upstream passage 12a and the bypass downstream passages 12b ₁ , 12b ₂ ; 12b ₃ , 12b ₄ throttle the intake passages 2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ . Bypasses 12 ₁ , 12 ₂ ; 12 ₃ , 12 ₄ that bypass the valves 5 ₁ , 5 ₂ ; 5 ₃ , 5 ₄ , respectively, are configured, and the bypass upstream passage 12 a has all bypasses 12 ₁ , 12 _2. A single passage common to 12 ₃ and 12 ₄ . The bypass control valve 10 passes the secondary air introduced into the single bypass upstream passage 12a through the bypass downstream passages 12b ₁ , 12b ₂ ; 12b ₃ , 12b ₄ and the intake passages 2 ₁ , 2 ₂ ; 2 ₃ , It has a function of distributing to each of the _four and controlling the amount of air distributed at the same time.

A specific structure of the bypasses 12 ₁ and 12 ₂ and the bypass control valve 10 on the first throttle body 1A side will be described based on FIGS. 1, 4, and 6 to 10. FIG.

A control block 15 is joined by a plurality of bolts 16 to one side surface of the first throttle body 1A along the arrangement direction of the intake passages 2 ₁ and 2 ₂ , and the cylindrical valve extending in the vertical direction is connected to the control block 15. A chamber 18 is provided, and the guide passage 9 that communicates the lower part of the air inlet chamber 8 with the lower part of the valve chamber 18 is provided from the first throttle body 1 </ b> A to the control block 15.

  For convenience of explanation, in the first and second throttle bodies 1A and 1B, the side where the control block 15 is disposed is the front side, and the opposite side is the rear side.

Distribution chambers 32 ₁ from the periphery of the two pairs over the front side surface of the first throttle body 1A of the bottom of the valve chamber 18, 32 _2; 32 _3, 32 ₄ are provided, a valve chamber 18 above the distribution chambers 32 _1, 32 _2; Two pairs of measuring holes 19 ₁ , 19 ₂ ; 19 ₃ , 19 ₄ communicating with 32 ₃ , 32 ₄ are formed in the peripheral wall of the valve chamber 18.

The valve chamber 18, the measuring holes 19 _1, 19 _2; the opening of 19 _3, 19 _4, piston-like valve body 26 to adjust over the fully opened from the fully closed is slidably fitted from above In this case, in order to prevent the rotation of the valve body 26, a key groove 27 is provided on the side surface of the valve body 26, and a key 28 engaged therewith is attached to the control block 15. An electric actuator 25 that opens and closes the valve body 26 is mounted in a mounting hole 29 formed in the control block 15 connected to the upper end of the valve chamber 18 and fixed to the control block 15 with a bolt. In the electric actuator 25, the output shaft 30 protruding downward is screwed into the screw hole 31 at the center of the valve body 26, and the output shaft 30 is moved up and down (opened / closed) by reversing the output shaft 30 forward and backward. )can do. Thus, the bypass control valve 10 is constituted by the valve body 26 and the electric actuator 25.

The control block 15 and the first throttle body 1A, the intermediate chamber 35 ₁ over the joint surface, which communicates via a communication hole 34 _1, 34 ₂ in the lower portion of the pair of distribution chambers 32 _1, 32 ₂
, 35 ₂ are provided, extending from these intermediate chambers 35 ₁ , 35 ₂ , and throttle valves 5 ₁ , 5 _2.
Through holes 36 ₁ , 36 ₂ opening in the intake passages 2 ₁ , 2 ₂ downstream of the first throttle body 1A are formed.

Thus, the measuring holes 19 ₁ , 19 ₂ , the distribution chambers 32 ₁ , 32 ₂ , the intermediate chambers 35 ₁ , 35 ₂ and the through holes 36 ₁ , 36 ₂ are provided with a pair of bypasses 12 ₁ on the first throttle body 1A side, 12 ₂ bypass downstream passages 12b ₁ and 12b ₂ are formed.

And the air inlet chamber 8, and the respective middle portions of the through hole 36 _1, 36 _2, it communicates with the idle air passage 37 _1, 37 ₂ may adjust these idle air passages 37 _1, 37 ₂ of the passage area, respectively A pair of idle adjustment screws 38 ₁ , 38 ₂ are screwed onto the first throttle body 1A (see also FIG. 12).

Next, a specific structure of the bypasses 12 ₃ and 12 ₄ on the second throttle body 1B side will be described with reference to FIGS. 1 to 3, 9, 11 and 12.

Of the first throttle body 1A, the joint surfaces of the control block 15, the pair of distribution chambers 32 _3, 32 intermediate chamber 35 ₃ is communicated with the _fourth, 35 ₄ are formed, the these intermediate chamber 35 _3, 35 ₄ 2 The first and second passages 39a and 39b reaching the intake passages 2 ₃ and 2 ₄ downstream of the throttle valves 5 ₃ and 5 ₄ of the throttle body 1B are as follows over the first and second throttle bodies 1A and 1B. Formed.

First passage 39a includes an intake passage 2 from the intermediate chamber 35 ₃ is located in the ₂ side and the first through hole 39 ₁ that extends to the second throttle body 1B side of the front wall of the first throttle body 1A, the first through hole 39 ₁ extends in the direction of the arrangement of the intake passages 2 ₃ and 2 ₄ so as to communicate with the first throttle body 1B, and forwards past the intake passage 2 ₃ inside the second throttle body 1B. a second through hole 39 ₂ opened to the front side of the second throttle body 1B bent to be formed in the second throttle body 1B so as to extend to the intake passage 2 ₃ from the front side of the second throttle body 1B The first through hole 39 ₃ is formed in a passage forming block 46 joined to the front side surface of the second throttle body 1B by a bolt 47 and communicates between the second and third through holes 39 ₂ and 39 ₃ . It is comprised with the communication recessed part 41a.

Thus, the measuring hole 19 ₃ , the distribution chamber 32 ₃ , the intermediate chamber 35 ₃ , and the first passage 39a are connected to the intake passage 2 _3.
Constitute the bypass downstream passage 12b ₃ of the side bypass 12 _3.

The second passage 39b proceeds partitions between the intake passage 2 _1, 2 ₂ of the first throttle body 1A from the intermediate chamber 35 ₄ located in the intake passage 2 ₁ side to the rear, and after the first throttle body 1A intake paths 2 ₁ through the side wall of the side 2 and along a _second array direction second fourth through hole 39 ₄ extending to the throttle body 1B side, the second throttle body so as to communicate with the fourth hole 39 ₄ 1B extends along the arrangement direction of the intake passages 2 ₃ and 2 ₄ in the rear side wall of the 1B, and bends toward the partition between the intake passages 2 ₃ and 2 _{4 of} the second throttle body 1B. a fifth through hole 39 ₅ which is open to the front side surface, a sixth through hole 39 ₆ extending from the front side of the second throttle body 1B in the intake passage 2 _4, are formed on the passage forming block 46 of the second throttle body 1B Te, communicating between the fifth and sixth holes 39 _5, 36 ₆ Composed of the second communicating recess 41b.

Thus, the measuring hole 19 ₄ , the distribution chamber 32 ₄ , the intermediate chamber 35 ₄ , and the first passage 39b are connected to the intake passage 2 _4.
Constitute the bypass downstream passage 12b ₄ of the side bypass 12 _4.

As shown in FIGS. 7 and 12, in the first throttle body 1A, the outer intake passage 2 _{1 is provided.}
Just above the bypass downstream passage 12b ₁ connected, the intake passage 2 ₄ side bypass downstream passage 12b ₄ of the intake paths 2 _1, 2 wherein passing the ₂ between the partition wall 4 through hole 39 ₄ is arranged . Thus, the bypass downstream passage 12b ₁ of intake paths 2 ₁ side, and the bypass downstream passage 12b ₄ of the intake passage 2 ₄ side, the plane of the first throttle body 1A as viewed from the intake paths 2 _1, 2 ₂ in the axial direction Some of them overlap each other visually.

In FIG. 1 to FIG. 3, a pair of hollow cylindrical communication bosses 14 a that are abutted with each other are provided on the opposing surfaces of the front and rear sidewalls of the first and second throttle bodies 1 </ b> A and 1 </ b> B. , 14b; 14c, 14d are formed integrally with the hollow portion of the communicating boss 14a of the front side of the first throttle body 1A is constituted with the first through hole 39 ₁ of the downstream end portion, communicating the front side of the second throttle body 1B hollow portion of the boss 14b has a second hole 39 ₂ of the upstream end. A seal member 48 surrounding the communication portion of the first and second through holes 39 ₁ and 39 ₂ is interposed at the joint portion of the communication bosses 14a and 14b.

The hollow portion of the communicating boss 14c of the rear side of the first throttle body 1A is constituted with the downstream end of the fourth through hole 39 _4, hollow portions communicating boss 14d on the rear side of the second throttle body 1B, the first 5 has an upstream end portion of the through hole 39 _5. A sealing member 48 surrounding the communicating portions of the fourth and fifth through holes 39 ₄ and 39 ₅ is interposed at the joint portion between the communicating bosses 14c and 14d.

The first to sixth holes 39 ₁ to 39 _6, cast vent or the first and second throttle bodies 1A by drilling, 1B to are those which are integrally formed, its processability port, by a plug 50 Closed.

The second throttle body 1B is provided with an air inlet chamber 42 that opens toward the air cleaner 3 between the first and second intake passages 2 ₃ and 2 ₄ , and the air inlet chamber 42 and the third and sixth passages. The idle air passages 37 ₃ and 37 ₄ communicate with the holes 39 ₃ and 39 _6, and a pair of idle adjustment screws 38 ₃ and 38 ₄ that can adjust the passage areas of the idle air passages 37 ₃ and 37 ₄ , respectively. Is screwed to the second throttle body 1B.

The idle air passages 37 ₁ , 37 ₂ ; 37 ₃ , 37 ₄ are idle air required for normal idling of the engine when the bypasses 12 ₁ , 12 ₂ ; 12 ₃ , 12 ₄ are fully closed by the bypass control valve 10. intended to secure the amount of the idle air quantity idle adjusting screw 38 _1, 38 _2; adjusted by 38 _3, 38 _4.

2 and 8, first and second throttle bodies 1A, the front portion of 1B, the first and second a part of the bypass downstream passage 12b ₃ of the intake path 2 ₃ side to the top hole 39 _1, 39 ₂ are formed, the injection valve mounting boss 49 _{1-49 4} for mounting the fuel injection valve 7 _{1-7 4} below them is formed. That is, the injection valve mounting bosses 49 ₁ to 49 ₄ are arranged on the downstream side of the first and second through holes 39 ₁ and 39 ₂ along the intake passages 2 ₁ to 2 ₄ . The _two first and second through holes 39 _1, 39, the fuel injection valve 7 _{1-7 4} the rear end and first and second throttle bodies 1A, and 1B each intake paths 2 ₁ to 2 ₄ The first and second through holes 39 ₁ and 39 ₂ and the fourth and fifth through holes 39 ₄ and 39 ₅ are formed in the vertical direction. The first and second throttle bodies 1A and 1B are formed at the same height position close to the upper ends.

  Next, the operation of this embodiment will be described.

When the engine is warming up, a control device (not shown) supplies a current corresponding to the engine temperature to the electric actuator 25 of the bypass control valve 10 to operate the electric actuator 25. Raise large, measuring holes 19 _1, 19 _2; 19 _3, 19 ₄ of the opening greatly adjusted. Therefore, in a state where the throttle valves 5 ₁ , 5 ₂ ; 5 ₃ , 5 ₄ are fully closed, the fast idle air supplied to the engine through the bypasses 12 ₁ , 12 ₂ ; 12 ₃ , 12 _{4 1,} 19 _2; 19 _3, 19 ₄ relatively more controlled manner, at the same time, the fuel injection valve 7 _1, 7 _2; 7 _3, 7 ₄ intake paths 2 ₁ and ₂ 2; 2 _3, 2 ₄ downstream Thus, fuel corresponding to the operation amount of the electric actuator 25 is injected, and the engine can maintain an appropriate first idling rotational speed so as to promote warm-up operation by receiving these supplies.

When the engine temperature with the progress of the warm-up operation is increased, the electric actuator 25 lowers the valve member 26 accordingly, measuring holes 19 _1, 19 _2; since 19 _3, decreases the 19 ₄ opening, The fast idle air supplied to the engine through the bypasses 12 ₁ , 12 ₂ ; 12 ₃ , 12 ₄ is reduced, and the engine speed decreases. When the engine temperature reaches a predetermined high temperature, the electric actuator 25 lowers the valve body 26 to the fully closed state and shuts off the bypasses 12 ₁ , 12 ₂ ; 12 ₃ , 12 ₄ , so that the intake passages 2 ₁ , 2 ₂ 2 ₃ , 2 ₄ throttle valves 5 ₁ , 5 ₂ ; 5 ₃ , 5 ₄ closed, idle air passages 37 ₁ , 37 ₂ ; 37 ₃ , 37 ₄ only supply minimal idle air to the engine As a result, the engine is controlled to the normal idle speed. At that time, idle air passages 37 _1, 37 _2; idle air quantity flowing through the 37 _3, 37 _4, the idle adjusting screw 38 _1, 38 _2; 38 _3, 38 can be adjusted individually by the _fourth reciprocating regulation.

  By the way, since the bypass control valve 10 is mounted on the first throttle body 1A side, a dedicated mounting member for the bypass control valve can be eliminated, and the structure of the intake device D can be simplified.

By the way, in such an intake device for a multi-cylinder engine, a pair of hollows that are abutted with each other are opposed to the opposing surfaces of the front and rear sidewalls of the first and second throttle bodies 1A and 1B. Cylindrical communication bosses 14a, 14b; 14c, 14d are integrally formed, and the hollow portion of the communication boss 14a on the first throttle body 1A side extends from the bypass control valve 10 and passes through the wall of the second throttle body 1B. first becomes hole 39 ₁ of the downstream end portion through the second hollow portion of the second throttle body 1B side of the communicating boss 14b extends through the the walls of the second throttle body 1B to the outside of the intake path 2 ₃ side on the upstream side end portion of the through-hole 39 _2, first and second through holes 39 _1, by 39 _2, the intake path 2 ₃ side portion of the bypass downstream passage 12b ₃ of the structure, also the first throttle body 1A side Boss Hollow portion of 4c becomes the fourth through hole 39 ₄ of the downstream end portion through the wall of the first throttle body 1A extending from the bypass control valve 10, the hollow portion of the second throttle body 1B side of the communicating boss 14d is on the upstream side end portion of the fifth hole 39 ₅ extending into the intake passage 2 ₄ outside the second throttle body 1B, these fourth and fifth through holes 39 _4, 39 _5, pass downstream of the intake path 2 ₃ side Since a part of the passage 12b ₃ is constructed, it is attached to the first throttle body 1A by abutting the communication bosses 14a, 14b; 14c, 14d to connect the first and second throttle bodies 1A, 1B. and extend from the bypass control valve 10 and the second throttle body 1B pair of intake paths 2 _3, 2 of the pair leading to ₄ bypass downstream passage 12b _3, 12b ₄ can be completed, thus Concrete can be simple and the assembling property is obtained an intake device for a good multi-cylinder engine.

Moreover, most of the pair of bypass downstream passages 12b ₃ and 12b ₄ are formed in the walls of the first and second throttle bodies 1A and 1B, so that the first and second throttle bodies 1A and 1B are moved outward. This can contribute to the downsizing of the intake system for multi-cylinder engines.

Further, a seal member 48 surrounding the communication portion of the first and second through holes 39 ₁ and 39 ₂ is interposed at the joint portion of the communication bosses 14a and 14b, and the joint portion of the communication bosses 14c and 14d. since the sealing member 48 which surrounds the communicating portion of the fourth and fifth holes 39 _4, 39 ₅ is interposed, the first and second through holes 39 _1, 39 between ₂ and 4 and 5 ensuring airtightness between the through hole 39 _4, 39 _5, an intake leakage from the communicating portion reliably prevented, it is possible to improve the accuracy of the bypass intake control.

Most of the pair of bypass downstream passages 12b ₃ and 12b ₄ are divided into front and rear side portions of the first and second throttle bodies 1A and 1B with the intake passages 2 ₃ and 2 ₄ interposed therebetween. Therefore, interference between the bypass downstream passages 12b ₃ and 12b ₄ can be easily and reliably avoided while ensuring a compact intake device.

At that time, extending from the bypass control valve 10, the fourth through hole 39 ₄ toward the outside of the intake passage 2 ₄ of the second throttle body 1B, a pair of intake paths of the first throttle body 1A 2 _1, 2 ₂ between Since it is formed so as to proceed rearward in the partition wall of the first throttle body 1A and then to the second throttle body 1B in the rear side portion of the first throttle body 1A, the partition wall between the intake passages 2 ₁ and 2 _{2 of} the first throttle body 1A is formed. , i.e. an intermediate wall for connecting the front side and back side of the first throttle body 1A will be utilized in the formation of the fourth through hole 39 _4, enhance space efficiency, compact intake system for a multi-cylinder engine Can contribute to the development.

Further, the intake passage 2 ₁ extends from the bypass control valve 10 and outside the first throttle body 1A.
A part of the bypass downstream passage 12b ₄ leading to the first throttle body 1A is connected to the intake passage 2 _1.
, Extending from the bypass control valve 10 in a plan view seen from the 2 _second axial since it is disposed in vertical relationship so as to overlap with the fourth through hole 39 ₄ through the partition wall between the intake paths 2 _1, 2 ₂ can while maintaining the compactness of the first throttle body 1A, facilitating interference with the bypass downstream passage 12b ₁ of intake paths 2 ₁ side and the bypass downstream passage 12b ₄ of the intake passage 2 ₄ side, to reliably avoid .

Further, in order to make the first throttle body 1A and the second throttle body 1B common, the same number of intake passages 2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ are provided in the respective throttle bodies 1A, 1B. The control block 15 joined to the front surface of 1A is equipped with the bypass control valve 10 and a plurality of bypass downstream passages 12b _{1 to} 12b from the bypass control valve 10 toward all the intake passages 2 ₁ to 2 _{4. 4} and part of the bypass downstream passages 12b ₃ and 12b ₄ toward the intake passages 2 ₃ and 2 ₄ are formed in the passage forming block 46 joined to the front surface of the second throttle body 1B. Therefore, by simply removing the control block 15 and the passage forming block 46, the first and second throttle bodies 1A and 1B can be shared, and their mass productivity is improved, and the multi-cylinder engine is increased. This can contribute to the cost reduction of the gin intake device. Further, by forming the complicatedly bent portions of the bypass downstream passages 12b _{1 to} 12b _{4 in} the control block 15 and the passage forming block 46, it is possible to improve workability.

The throttle body 1A, the front portion of the 1B, the fuel injection valve 7 _{1-7 4} injection valve mounting boss 49 _{1-49 4} for injecting fuel into each intake passage ₂₁ to ₂₄ are formed, these injection The valve mounting bosses 49 ₁ to 49 ₄ are respectively connected to the intake passages 2 ₁ and 2 from straight portions extending in the arrangement direction of the throttle bodies 1A and 1B at the front sides of the throttle bodies 1A and 1B of the bypass downstream passage 12b _{3. 2} , the straight portion of the bypass downstream passage 12b ₃ and the injection valve mounting bosses 49 ₁ to 49 ₄ may be disposed on the same front side of the throttle bodies 1A and 1B. Next, a second embodiment of the present invention shown in FIG. 13 will be described.

In the second embodiment, a pair of both end portions of the tubular body 51 are formed on the inner peripheral surfaces of the communication bosses 14a, 14b; 14c, 14d formed on the opposing surfaces of the first and second throttle bodies 1A, 1B. Of the first and second through holes 39 ₁ and 39 _{2 and} between the fourth and fifth through holes 39 ₄ and 39 ₅ , respectively. Communicated. Since other configurations are the same as those of the previous embodiment, portions corresponding to those of the previous embodiment in FIG. 13 are denoted by the same reference numerals, and redundant description is omitted.

According to the second embodiment, even when a gap exists between the opposing bosses 14a, 14b; 14c, 14d, the first and second through holes 39 ₁ , 39 ₂ and the fourth and fourth bosses 14a, 14b; It is possible to ensure communication without air leakage between the five through holes 39 ₄ and 39 ₅ .

As mentioned above, although the Example of this invention was described, this invention is not limited to it, A various design change is possible in the range which does not deviate from the summary. For example, the injection valve mounting bosses 49 ₁ to 49 ₄ are arranged on the rear side of both throttle bodies 1A and 1B where the bypass downstream passage 12b ₄ is formed, in the direction in which the throttle bodies 1A and 1B of the bypass downstream passage 12b ₄ are arranged. the straight line portion along may be located downstream of the intake paths 2 ₁ to 2 _4.

D: Multi-cylinder engine intake system 1A: One throttle body (first throttle body)
1 B ... the other throttle body (second throttle body)
2 ₁ , 2 ₂ ... One throttle body intake passage 2 ₃ , 2 ₄ ... The other throttle body intake passage 5 ₁ , 5 ₂ ... One throttle body side throttle valve 5 ₃ . 5 ₄ ... Throttle valve 10 on the other throttle body 10... Bypass control valves 12 ₁ , 12 ₂ ... Bypass 12 ₃ , 12 _{4 on the} other throttle body side Side bypass 12b ₁ , 12b ₂ , bypass downstream passage 12b ₃ , 12b _{4 on} one throttle body side, bypass downstream passage 39a on the other throttle body side, first passage 39b,. Second passages 39 _{1 to} 39 ₆ ... First to sixth through holes 49... Seal member 51.

Claims (8)

One and the other throttle bodies (1A, 1B) joined in parallel to each other, intake passages (2 ₁ , 2) connected to intake ports (E ₁ , E ₂ ; E ₃ , E ₄ ) of a plurality of cylinders of the engine, respectively. ₂ ; 2 ₃ , 2 ₄ ) and throttle valves (5 ₁ , 5 ₂ ; 5 ₃ , 5 ₄ ) for opening and closing each intake passage (2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ ), The other throttle body (1A, 1B) has an upstream end at the atmosphere or each intake passage (2 ₁ , 2 ₂ ; 2 ₃ , 2) upstream of each throttle valve (5 ₁ , 5 ₂ ; 5 ₃ , 5 ₄ ). 2 ₄ ) and a plurality of bypasses (12 ₁ ) whose other ends open to the intake passages (2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ ) downstream of the throttle valves (5 ₁ , 5 ₂ ). , 12 _2; 12 _3, 12 ₄₎ provided with a, these bypass (12 _1, 12 _2; 12 _3, 12 _4), by which opening and closing the Comprising scan control valve (10) provided in an intake device for a multi-cylinder engine,
The bypass control valve (10) is attached to one throttle body (1A) on one side of the throttle body (1A, 1B) along the arrangement direction of the throttle body (1A) . Two intake passages (2 ₃ , 2 ₄ )
The first intake air is extended from the bypass control valve (10) to one side and the other side of the throttle bodies (1A, 1B) facing each other across the intake passage (2 ₁ to 2 ₄ ). a first bypass downstream passage reaching the road _{(2 3) (12b 3)} , the second bypass downstream passage reaching said second intake path extending from the bypass control valve _{(10) (2 4) (} 12b 4) Each form
These first and second bypass downstream passages (12b ₃ , 12b ₄ ) extend from the bypass control valve (10), pass through the wall of one throttle body (1A), and pass through one throttle body (1A). , The first through hole (39 ₁ , 39 ₄ ) opening the downstream end on the joint surface with the other throttle body (1B), and the other end of the throttle body (1B) through the wall, The other throttle body (1B) is opened at the joint surface with one throttle body (1A) so as to communicate with the downstream end of _one through hole (39 ₁ , 39 ₄ ), and the downstream end is connected to the other throttle body The first through-hole of the second bypass downstream passage (12b ₄ ) is constituted by _second through holes (39 ₂ , 39 ₅ ) that open to the intake passages (2 ₃ , 2 ₄ ) of the body (1B) . the through hole (39 _4), which is one of Ro From said one side of Torubodi (1A), therewith thereby formed to pass through the wall of and said other side extends to the other side opposite to the communicating with the first hole (39 ₄₎ The second through hole (39 ₅ ) of the second bypass downstream passage (12b ₄ ) passes through the other side wall of the other throttle body (1B) on the same side as the one throttle body (1A). An intake device for a multi-cylinder engine, characterized by being formed to pass through . The intake system for a multi-cylinder engine according to claim 1,
The throttle body (1A, 1B) is disposed with the downstream side of each intake passage (2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ ) facing downward, and the first and second bypass downstream passages (12b ₃ , 12 b ₄ ), the portions (39 ₁ , 39 ₂ ; 39 ₄ , 39 ₅ ) extending in the arrangement direction of the throttle bodies (1A, 1B) are arranged at the upper ends of the throttle bodies (1A, 1B) in the vertical direction. An intake system for a multi-cylinder engine, characterized in that it is formed at the same height position . The intake device for a multi-cylinder engine according to claim 1 or 2 ,
A bypass downstream passage (12b ₁ ) of the bypass (12 ₁ ) extending from the bypass control valve (10) and reaching the intake passage (2 ₁ ) of _one throttle body (1A), part of which is one throttle body (1A) is formed in one throttle body (1A) so as to overlap a part of the first through hole (39 ₄ ) in a plan view as viewed from the axial direction of the intake passage (2 ₁ ). A multi-cylinder engine intake system. The multi-cylinder engine intake device according to any one of claims 1 to 3 ,
In order to make one throttle body (1A) and the other throttle body (1B) common, each throttle body (1A, 1B) is provided with the same number of intake passages (2 ₁ , 2 ₂ ; 2 ₃ , 2 ₄ ) The bypass control valve (10) is attached to a control block (15) joined to one side surface of the one throttle body (1A), and all the intake passages (2 ₁ ,. 2 ₂ ; 2 ₃ , 2 ₄ ), forming a part of a plurality of bypass downstream passages (12b _{1 to} 12b ₄ ), and a passage forming block (46) joined to one side surface of the other throttle body (1B) ), A part of a bypass downstream passage (12b ₃ , 12b ₄ ) toward the other intake passage (2 ₃ , 2 ₄ ) is formed. The multi-cylinder engine intake device according to any one of claims 1 to 4 ,
On one side or the other side of the throttle bodies (1A, 1B), the fuel injection valve (7 ₁ to 7 ₄₎ forming an injection valve mounting bosses for mounting (49 ₁ to 49 _4), the injection valve mount A portion (39 ₁ , 39 ₂ ; 39) of the boss (49 ₁ to 49 ₄ ) extending in the arrangement direction of the throttle bodies (1A, 1B) of the first and second bypass downstream passages (12b ₃ , 12b ₄ ). ₄ , 39 ₅ ), an intake device for a multi-cylinder engine, which is arranged downstream from each intake passage (2 ₁ to 2 ₄ ). The intake device for a multi-cylinder engine according to claim 5,
The intake passage (2 ₁  , 2 ₂  ; 2 _Three  , 2 _Four  ) In the direction along the axis of the first bypass downstream passage (12b _Three  ) Of the throttle body (1A, 1B) extending in the arrangement direction (39 ₁  , 39 ₂  ) Is the fuel injection valve (7 ₁  ~ 7 _Four  ) And each intake passage (2 of the throttle body (1A, 1B)) ₁  ~ 2 _Four  Inlet device for multi-cylinder engine, characterized in that it is formed between the upstream end portion and The multi-cylinder engine intake device according to any one of claims 1 to 6,
Between the joint surface of one throttle body (1A) and the other throttle body (1B), between the first through holes (39 ₁ , 39 ₄ ) and the second through holes (39 ₂ , 39 ₅ ) An intake device for a multi-cylinder engine, wherein a seal member (48) surrounding the communication portion is interposed. The multi-cylinder engine intake device according to any one of claims 1 to 7,
Between the first through hole (39 ₁ , 39 ₄ ) and the second through hole (39 ₂ , 39 ₅ ), respectively, are opposed to one throttle body (1A) and the other throttle body (1B). An intake device for a multi-cylinder engine, characterized in that it communicates via a pipe body (51) fitted through a seal member (52).

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