JP2011163162A - Intake control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake control device for an internal combustion engine, effectively increasing rigidity of especially the gear storage section of a control housing integrally molded with a throttle body. <P>SOLUTION: In this intake control device for the internal combustion engine, the synthetic resin control housing 3 includes a cylindrical motor storage section 3a integrally connected to one side of the throttle body 1, arranged parallel to a valve stem 6, and storing an electric motor 20, and the flat gear storage section 3b extending long in a direction perpendicular to the valve stem 6 from one end of the motor storage section 3a, integrally connected to the throttle body 1, and storing a speed reduction gear device 21. A pair or long ribs 40 extending in a direction with the valve stem 6 and electric motor 20 arranged while being opposed to each other at intervals and a plurality of connection ribs 41, 42 integrally connecting a portion between both the long ribs 40 are formed on the outer surface of the gear storage section 3b. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  In the present invention, a throttle body having an intake passage and a control housing adjacent thereto are integrally formed of synthetic resin, and a throttle valve for opening and closing the intake passage is attached to a valve shaft rotatably supported by the throttle body. The control housing is an intake control device for an internal combustion engine that houses an electric motor and a reduction gear device that decelerates the rotation of the electric motor and transmits it to the valve shaft. A cylindrical motor housing portion that is integrally connected to one side portion of the throttle body and is arranged in parallel with the valve shaft, and houses the electric motor, and extends from one end of the motor housing portion in a direction perpendicular to the valve shaft. The present invention relates to an improvement in a bag that is formed by a flat gear housing portion that extends and is integrally connected to the throttle body and that houses the reduction gear device.

  Such an intake control device for an internal combustion engine is known as disclosed in Patent Document 1 below.

JP 2005-54633 A

  In the conventional intake control device for an internal combustion engine, when the valve shaft of the throttle valve is driven through the reduction gear device by the operation of the electric motor, the driving force must be supported by the gear housing portion. In particular, it is required to enhance the rigidity of the synthetic resin gear housing. If the gear housing part has low rigidity and the gear reaction part is distorted by the driving reaction force, the distortion spreads to the throttle body, especially the inner peripheral surface of the intake passage, and particularly when the throttle valve is at an idle opening. The intake air amount will be changed. Such fluctuations in intake air amount cause the idling of the internal combustion engine to become unstable and adversely affect the exhaust gas properties and fuel consumption.

  However, conventionally, little consideration has been given to enhancing the rigidity of the gear housing portion made of synthetic resin.

  The present invention has been made in view of such circumstances, and an intake control device for an internal combustion engine that can effectively enhance the rigidity of a control housing formed integrally with a throttle body, in particular, a gear housing portion. The purpose is to provide.

  To achieve the above object, according to the present invention, a throttle body having an intake passage and a control housing adjacent to the throttle body are integrally formed of a synthetic resin, and the intake shaft is mounted on a valve shaft rotatably supported by the throttle body. An intake control device for an internal combustion engine, which is provided with a throttle valve for opening and closing a path, and in which a control housing houses an electric motor and a reduction gear device that decelerates the rotation of the electric motor and transmits it to the valve shaft. The control housing is integrally connected to one side portion of the throttle body and arranged in parallel with the valve shaft, and includes a cylindrical motor housing portion for housing the electric motor, and an end portion of the motor housing portion from the one end portion. In a configuration that includes a flat gear housing portion that extends in a direction perpendicular to the valve shaft and that is integrally connected to the throttle body and that houses the reduction gear device, A pair of long ribs extending in the arrangement direction of the valve shaft and the electric motor while being opposed to each other on the outer surface of the housing portion, and a plurality of connecting ribs integrally connecting the long ribs The first feature is that the above is formed.

  According to the present invention, in addition to the first feature, as the plurality of connecting ribs, a connecting rib orthogonal to the long rib and a connecting rib crossing the long rib are mixed. It is characterized by.

  In addition to the first feature of the present invention, the reduction gear device is rotatably supported by a primary drive gear fixed to the output shaft of the electric motor and an intermediate shaft supported by the gear housing portion. A primary driven gear meshed with the primary drive gear, a secondary drive gear integrally formed on one side of the primary driven gear, and meshed with the secondary drive gear fixed to the valve shaft Secondary output gears, and at least three of the connecting ribs, the output shaft while being orthogonal to the long ribs in a side view when the gear housing portion is viewed from the protruding side of the long ribs, A third feature is that each of the intermediate shaft and the valve shaft is disposed on each axis.

  Furthermore, in addition to the first feature, the present invention provides a fourth feature in which, with respect to the mutual spacing of the connecting ribs, the spacing on the motor housing portion side is set smaller than the spacing on the throttle body side. To do.

  Furthermore, in addition to the third feature, the present invention provides a support boss that integrally projects from the bottom surface of the gear housing portion on the throttle body side and supports the intermediate shaft, and the gear housing. A fifth feature is that ribs are formed to connect the inner surfaces of the portions facing each other.

  Furthermore, in addition to any of the first to fourth features, the present invention has formed a cylindrical gate portion having a diameter larger than the rib thickness at a plurality of locations of the long rib or the connecting rib. Is a sixth feature.

  According to the first aspect of the present invention, the pair of long ribs extending in the arrangement direction of the valve shaft and the electric motor while facing the outer surface of the gear housing portion with a space therebetween, and both the long ribs By forming a plurality of connecting ribs that connect them together, it is possible to effectively strengthen the rigidity of the gear housing, and while it is made of synthetic resin, Since it is not deformed by the driving reaction force and is not deformed even if it is vibrated from the internal combustion engine side, the driving force of the electric motor can be efficiently transmitted to the valve shaft through the reduction gear device. Further, distortion of the inner peripheral surface of the intake passage can be prevented, and the intake air amount controlled by the throttle valve can be stabilized.

  According to the second feature of the present invention, as the plurality of connecting ribs, a connecting rib orthogonal to the long rib and a connecting rib obliquely intersecting the long rib are mixed, so that a pair of long ribs is provided. A truss structure is formed between the scale ribs, which can further enhance the rigidity of the gear housing portion.

  According to the third aspect of the present invention, the output shaft, the intermediate shaft, and the valve are formed so that at least three of the connecting ribs are orthogonal to the long rib in a side view when the gear housing portion is viewed from the protruding side of the long rib. By arranging the shafts on the respective axes, the gear housing portion can be effectively reinforced around the output shaft, the intermediate shaft, and the valve shaft, and deformation thereof can be prevented.

  According to the fourth feature of the present invention, since the number of connecting ribs is large on the motor housing side and is reduced on the throttle body side, the number of connecting ribs used on the motor housing side is reduced as much as possible. The gear housing portion can be effectively reinforced. Therefore, even if the motor housing portion receives a large driving reaction force of the electric motor 20 or has a large vibration energy when excited from the internal combustion engine side, the gear housing serving as the base of the motor housing portion is used. The deformation of the part can be prevented.

  According to the fifth feature of the present invention, the bottom surface of the gear housing portion on the throttle body side protrudes integrally with the bottom surface and supports the intermediate shaft, and the gear housing portion faces each other. By forming ribs that connect the inner side surfaces to each other, the ribs cooperate with the outer long ribs and the connecting ribs on the outside to reinforce the gear housing part more effectively. Deformation can be prevented more reliably, and at the same time, the support boss can be reinforced to increase the support rigidity of the intermediate shaft.

  According to the sixth aspect of the present invention, during injection molding of the throttle body and the control housing, the control resin passes through the narrow cavities corresponding to the various ribs while the molten resin forms the gate portion through the gate of the mold. In addition, a wide cavity corresponding to the throttle body is filled, and it is possible to obtain a high-quality synthetic resin throttle body and control housing that is surely filled and has no nest.

1 is a cross-sectional view of an intake control device for an internal combustion engine according to an embodiment of the present invention. The corresponding figure with FIG. 1 which shows the throttle body with a control housing. FIG. 3 is a view taken in the direction of arrow 3 in FIG. 2. FIG. 4 is a view taken in the direction of arrow 4 in FIG. 3. FIG. 5 is a view taken in the direction of arrow 5 in FIG. 3. FIG. 6 is a sectional view taken along line 6-6 of FIG. FIG. 7 is a sectional view taken along line 7-7 in FIG. Explanatory drawing of the press fit procedure of a ball bearing to a bearing holder. The perspective view of a press-fit receiving jig.

  Embodiments of the present invention will be described below on the basis of preferred embodiments of the present invention shown in the accompanying drawings.

  In FIG. 1, FIG. 2 and FIG. 6, an intake control device for an internal combustion engine mounted on a vehicle such as a motorcycle or an automobile is composed of a synthetic resin throttle body 1 having an intake passage 2 at the center, and an integrated body. The main body is a control housing 3 made of synthetic resin.

  The throttle body 1 has a pair of bearing bosses 4 and 4 integrally on the left and right side walls thereof, and a mounting flange 5 having a square basic shape is provided at the downstream end of the intake passage 2 of the throttle body 1. It is integrally formed.

  A pair of left and right ball bearings 7 and 7 for rotatably supporting the valve shaft 6 crossing the intake passage 2 are attached to the bearing bosses 4 and 4 via bearing holders 8 and 8, respectively. A throttle valve 9 for opening and closing the intake passage 2 is fixed. One bearing holder 8 is fitted with a ball bearing 7 on the same side and a cap 10 covering one end surface of the valve shaft 6, and the other end of the valve shaft 6 extends into the control housing 3. .

  The valve shaft 6 and the throttle valve 9 are disposed offset from the central portion of the intake passage 2 to the downstream side in the intake flow direction. The mounting flange 5 is provided with a plurality of bolt holes 11, 11... For bolting this to a mounting flange on the intake manifold side of the internal combustion engine (not shown).

  Next, a structure for attaching the bearings 7 and 7 to the bearing bosses 4 and 4 will be described.

  At the time of injection molding of the throttle body 1 with synthetic resin, metal bearing holders 8 and 8 made of metal are embedded in the bearing bosses 4 and 4 by insert molding. At that time, the bearing holders 8 and 8 are arranged so that the respective inner end surfaces 8 a are located on the radially outer side of the intake passage 2. A recess 12 exposing a part of the inner end face 8a is formed so as to open to the downstream end face of the throttle body 1, that is, the end face of the mounting flange 5. In the illustrated example, the recess 12 is formed in an annular shape so as to surround the intake passage 2 on the downstream side of the throttle valve 9, and so that the bottom surface ends beyond the axis of the valve shaft 6 to the upstream side of the intake passage 2. Further, the annular recess 12 is formed such that the inner peripheral surface on the inner side thereof has a cylindrical shape concentric with the inner peripheral surface of the intake passage 2 and the inner peripheral surface on the outer side forms a polygon (FIGS. 2 and 2). 5).

  As shown in FIGS. 6 and 7, a portion of the inner end surface 8 a of the bearing holder 8 that is more than half a circumference is exposed in the recess 12, and the remaining portion is buried in the bearing boss 4. A plurality of annular anchor grooves 13 are formed on the outer peripheral surface of the bearing holder 8 to reinforce the coupling force with the bearing boss 4.

  After the bearing holder 8 is embedded in the bearing boss 4 by insert molding in this way, as shown in FIG. 8, the ball bearing 7 is press-fitted into the bearing holder 8 from the outer end side thereof by the press-fitting jig J2. At that time, the press-fitting receiving jig J1 is inserted into the concave portion 12 in advance and waited.

  As shown in FIG. 9, the press-fitting jig J1 is formed of a polygonal cylinder corresponding to the polygonal inner peripheral surface of the outer side of the recess 12, and a pair of opposed flat walls 15, Are provided with notches 16 and 16 that allow the base of the pair of bearing bosses 4 and 4 to be received, and a support portion 17 that can receive an exposed portion of the inner end surface 8a of the bearing holder 8 to the recess 12.

  Thus, the press-fitting receiving jig J1 inserted into the recess 12 first receives the roots of the bearing bosses 4 and 4 in the notches 16 and 16 and first enters the recess 12 on the inner end surface 8a of the left or right bearing holder 8. In this state, the ball bearing 7 is press-fitted into the one bearing holder 8 from the outer end side. Therefore, the press-fitting load of the ball bearing 7 to the bearing holder 8 by the press-fitting jig J2 is received by the press-fitting receiving jig J1, so that the ball bearing 7 is supported without bearing the press-fitting load on the throttle body 1. The holder 8 can be securely press-fitted.

  In addition, since the press-fitting receiving jig J1 is inserted into the recess 12 that is radially outside the intake passage 2 and is isolated from it, the press-fitting receiving jig J1 is inserted into the recess 12 and waits. There is no concern of damaging the inner surface of the intake passage 2 with the tool J1. Therefore, the press-fitting jig J1 can be easily handled, which can contribute to the improvement of productivity and the cost reduction.

  Further, since the portion of the inner end surface 8a of the bearing holder 8 is more than half a circumference exposed to the recess 12 and received by the press-fitting receiving jig J1, the posture of the bearing holder 8 is stabilized and the ball bearing 7 is press-fitted smoothly and accurately. be able to. In addition, since the remaining portion of the inner end face 8a of the bearing holder 8 is buried in the bearing boss 4, a strong coupling state between the bearing boss 4 and the bearing holder 8 can be ensured.

  On the other hand, since the press-fitting receiving jig J1 is composed of a polygonal cylinder, it has high bending rigidity and can firmly support the bearing holder 8 against the press-fitting load. Further, since the recess 12 is opened at the downstream end face of the throttle body 1 that is relatively close to the valve shaft 6 and the throttle valve 9, the depth can be made as shallow as possible. As a result, the recess 12 is inserted into the recess 12. The length of the press-fitting receiving jig J1 can be shortened as much as possible to further increase the bending rigidity.

  In order to regulate the press-fitting depth of the ball bearing 7 into the bearing holder 8, an inward flange 18 with which the inner end of the ball bearing 7 abuts is formed at the inner end of the bearing holder 8 (FIGS. 1 and 2).

  After the ball bearing 7 is press-fitted into the one bearing holder 8, the ball bearing 7 is press-fitted into the other bearing holder 8 in the same manner.

  When the mounting flange 5 is bolted to a mounting flange on the intake manifold side (not shown), the recess 12 is closed by the mounting flange on the intake manifold side so that dust and the like do not enter.

  1 to 3 again, the control housing 3 is integrally formed with the throttle body 1 with synthetic resin from the one bearing boss 4 to two sides forming a right angle of the mounting flange 5.

  The control housing 3 includes a cylindrical motor housing portion 3a connected to one side of the mounting flange 5 and arranged in parallel with the valve shaft 6, and a valve shaft 6 from one end in the axial direction of the motor housing portion 3a. The gear housing 3b is a flat and substantially rectangular parallelepiped gear housing 3b extending in a direction perpendicular to the bearing boss 4, and the surface of the gear housing 3b opposite to the throttle body 1 is an open surface. Yes. The motor accommodating portion 3a accommodates the electric motor 20, and the gear accommodating portion 3b accommodates a reduction gear device 21 that decelerates the rotation of the electric motor 20 and transmits it to the valve shaft 6. A synthetic resin cover 22 covering the device 21 is joined to the open surface of the control housing 3 by screws 23.

  The reduction gear device 21 includes a primary drive gear 26 fixed to the output shaft 25 of the electric motor 20, a primary driven gear 26 ′ rotatably supported on the intermediate shaft 27 and meshed with the primary drive gear 26, A secondary drive gear 28 integrally formed on one side of the primary driven gear 26 ′, and a sector type secondary driven gear 28 ′ fixed to the valve shaft 6 by a nut 29 and meshing with the secondary drive gear 28. The rotation of the output shaft 25 of the electric motor 20 is decelerated in two steps and transmitted to the valve shaft 6 so that the throttle valve 9 can be opened and closed. Each gear of the reduction gear device 21 is a spur gear, and the valve shaft 6, the output shaft 25, and the intermediate shaft 27 are arranged such that their axis lines are orthogonal to the axis line of the intake passage 2 and are parallel to each other. The intermediate shaft 27 is fixedly supported at one end by a cylindrical support boss 30 formed integrally with the control housing 3 by insert molding, and the other end is supported by being fitted into a support hole 31 provided in the cover 22. . The secondary driven gear 28 ′ is connected to a closing spring 32 made of a torsion coil spring that urges the secondary driven gear 28 ′ in the closing direction of the throttle valve 9.

  A throttle opening sensor 33 that detects the opening of the throttle valve 9 is provided between the valve shaft 6 of the throttle valve 9 and the cover 22. This throttle opening sensor 33 is a known sensor that takes out the opening of the throttle valve 9 as an electrical signal, and is attached to the end of a socket-type nut 29 that fixes the secondary driven gear 28 'to the valve shaft 6. And a receiver 35 attached to the cover 22 so as to face the transmitter 34.

  Each part of the control housing 3 is formed with ribs for reinforcing it as follows. First, in FIG. 3 to FIG. 5, the gear housing 3 b has a flat, substantially rectangular parallelepiped shape having the arrangement direction of the valve shaft 6 and the electric motor 20 as long sides. As shown in FIGS. 4 and 5, a pair of opposing sides of the outer side on the long side of the gear housing 3b and the outer side on the short side near the valve shaft 6 are spaced apart from each other by a certain distance. The long ribs 40, 40 and a plurality of connecting ribs 41, 41,..., 42, 42, which integrally connect the long ribs 40, 40 at least on the long side are formed. At this time, at least three connecting ribs 41 are provided on the output shaft 25, the intermediate shaft 27, and the valve shaft 6 while being orthogonal to the long ribs 40, 40 in a side view when the gear housing 3 b is viewed from the long side. Each is arranged on an axis. The other connecting ribs 42 are disposed so as to cross the long ribs 40, 40.

  As described above, the gear housing portion 3b is effectively strengthened by the pair of long ribs 40, 40 and the plurality of connecting ribs 41, 41,..., 42, 42,. Although it is made of synthetic resin, it is not deformed by the driving reaction force during operation of the electric motor 20, and it is not deformed even if it is vibrated from the internal combustion engine side. The force can be efficiently transmitted to the valve shaft 6 via the reduction gear device 21, the inner peripheral surface of the intake passage 2 can be prevented from being distorted, and the intake air amount controlled by the throttle valve 9 can be stabilized. .

  In particular, mixing the connecting ribs with those 41 orthogonal to the long ribs 40 and 40 and those oblique with each other constitutes a truss structure between the pair of long ribs 40 and 40. Since the rigidity enhancement of the gear housing portion is further promoted, it is extremely effective for preventing deformation of the gear housing portion 3b.

  Further, at least three connecting ribs 41 orthogonal to the long ribs 40, 40 are provided on the axis of the output shaft 25, the intermediate shaft 27 and the valve shaft 6 in a side view when the gear housing portion 3 b is viewed from the long side. As a result, the gear housing portion 3b can be effectively reinforced around the output shaft 25, the intermediate shaft 27, and the valve shaft 6, thereby preventing deformation thereof.

  Further, the mutual spacing between the connecting ribs 41, 41,..., 42, 42,. In this way, the number of connecting ribs 41, 41..., 42, 42... Is increased on the motor housing 3a side and decreased on the throttle body 1 side, so that the connecting ribs 41, 41. The gear housing portion 3b on the motor housing portion 3a side can be effectively reinforced while minimizing the number used. Therefore, even if the motor housing portion 3a receives a large driving reaction force of the electric motor 20 or has a large vibration energy when excited from the internal combustion engine side, it becomes the root of the motor housing portion 3a. The deformation of the gear housing portion 3b can be prevented.

  Further, on the bottom surface of the gear housing portion 3b opposite to the open surface, there are a plurality of ribs 43 that connect the support boss 30 and the opposing inner surfaces on the long sides of the gear housing portion 3b. 43 is formed. In the illustrated example, a pair of ribs 43 and 43 are formed so as to connect the opposing inner side surfaces on the long side while crossing in an X shape at the support boss 30. The ribs 43, 43 cooperate with the outer long ribs 40, 40 and the connecting ribs 41, 41 ...; 42, 42 ... to reinforce the gear housing portion 3b more effectively. Deformation can be prevented more reliably, and at the same time, the support boss 30 can be reinforced to increase the support rigidity of the intermediate shaft 27 and to stabilize the support of the primary driven gear 26 ′ and the secondary drive gear 28.

  Further, a plurality of ribs 44, 44... Orthogonal to the grid are also formed on the outer peripheral surface of the motor housing 3a. Thereby, since the motor accommodating part 3a is reinforced, the support rigidity with respect to the electric motor 20 of the motor accommodating part 3a can be improved.

  A cylindrical gate portion 45 having a diameter larger than the wall thickness is formed at a plurality of locations of the various ribs 40 to 44. These gate portions 45 are portions formed by a mold gate when the throttle body 1 and the control housing 3 are injection molded. Therefore, at the time of injection molding, the molten resin corresponds to the various ribs 40 to 44 from the gate. Since the narrow cavity is filled into the corresponding wide cavity of the control housing 3 and the throttle body 1, it is possible to obtain a high-quality synthetic resin throttle body 1 and control housing 3 that are surely filled and have no nest. .

  The present invention is not limited to the above embodiment, and various design changes can be made without departing from the scope of the invention. For example, instead of the ball bearing 7, other types of bearings such as a plain bearing can be used.

DESCRIPTION OF SYMBOLS 1 ... Throttle body 2 ... Intake passage 3 ... Control housing 3a ... Motor housing part 3b ... Gear housing part 6 ... Valve shaft 9 ... Throttle valve 20 ... Electric motor 21 ... Reduction gear device 25 ... Output shaft 26 ... Primary drive gear 26 '... Primary driven gear 27 ... Intermediate shaft 28 ... Secondary drive gear 28' ..Secondary driven gear 30 ... support boss 40 ... long rib 41 ... connecting rib (perpendicular to long rib)
42 ... Connecting rib (oblique with long rib)
43 ... Rib 45 ... Gate

Claims (6)

A throttle body (1) having an intake passage (2) and a control housing (3) adjacent to the throttle body (2) are integrally formed of synthetic resin, and are mounted on a valve shaft (6) rotatably supported on the throttle body (1). , A throttle valve (9) for opening and closing the intake passage (2) is provided, and the control housing (3) is provided with an electric motor (20) and the rotation of the electric motor (20) to reduce the rotation of the valve shaft ( 6) An intake air control device for an internal combustion engine that houses a reduction gear device (21) that transmits to the internal combustion engine, wherein the control housing (3) is integrally connected to one side of the throttle body (1) and the valve A cylindrical motor housing portion (3a) that is arranged in parallel with the shaft (6) and houses the electric motor (20), and is orthogonal to the valve shaft (6) from one end of the motor housing portion (3a). The throttle body extends long in the direction (1) integrally connected to, in what constituted out with the reduction gear device flat gear accommodating portion for accommodating a (21) (3b),
A pair of long ribs (40) extending in the arrangement direction of the valve shaft (6) and the electric motor (20) while facing the outer surface of the gear accommodating portion (3b) with a space therebetween, and both lengths thereof An intake control device for an internal combustion engine, comprising a plurality of connecting ribs (41, 42) that integrally connect between the scale ribs (40). The intake control device for an internal combustion engine according to claim 1,
As the plurality of connecting ribs, a connecting rib (41) orthogonal to the long rib (40) and a connecting rib (42) obliquely intersecting the long rib (40) are mixed. Intake control device for an internal combustion engine. The intake control device for an internal combustion engine according to claim 1,
The reduction gear device (21) includes a primary drive gear (26) fixed to the output shaft (25) of the electric motor (20), and an intermediate shaft (27) supported by the gear housing portion (3b). And a primary driven gear (26 ') meshed with the primary drive gear (26) and a secondary drive gear integrally formed on one side of the primary driven gear (26'). (28) and a secondary driven gear (28 ') fixed to the valve shaft (6) and meshing with the secondary drive gear (28), and at least three connecting ribs (41) are formed. The output shaft (25), the intermediate shaft (27), and the gear housing (3b) are orthogonal to the long rib (40) in a side view as seen from the protruding side of the long rib (40). An intake control device for an internal combustion engine, which is disposed on each axis of the valve shaft (6). The intake control device for an internal combustion engine according to claim 1,
Intake control for an internal combustion engine, characterized in that the interval on the motor housing part (3a) side is set smaller than the interval on the throttle body (1) side with respect to the mutual interval between the connecting ribs (41, 42). apparatus. The intake control device for an internal combustion engine according to claim 3,
On the bottom surface of the gear housing portion (3b) on the throttle body (1) side, a support boss (30) projecting integrally with the bottom surface and supporting the intermediate shaft (27), and the gear housing portion ( 3. An intake air control device for an internal combustion engine, characterized in that a rib (43) is formed to connect each of the inner surfaces facing each other in 3b). The intake control device for an internal combustion engine according to any one of claims 1 to 4,
Intake control for an internal combustion engine, wherein a cylindrical gate portion (45) having a diameter larger than the rib thickness is formed at a plurality of locations of the long rib (40) or the connecting rib (41, 42). apparatus.

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