JP2009162071A - Intake manifold device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To certainly improve airtightness when the length of an air intake passage is changed by a passage length changing section in a simple configuration. <P>SOLUTION: Each valve 40 forming the passage length changing section 18 is rotatably supported by an intake manifold 14 through a shaft 38 connected to one end and is provided with a seal member 50 formed of elastic material for covering the other end and both sides of the valve 40. Seal is ensured by abutting the first seal portion 50a of the seal member 50 on the inner wall surface of the air intake passage 16, and also seal is ensured by abutment of the second seal portion 50b of the seal member 50 on the inside wall surfaces 30a, 30b of the air intake passage 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an intake manifold device for an internal combustion engine, and more particularly to an intake manifold device for an internal combustion engine having a passage length switching portion capable of switching the length of an intake passage through which intake air flows.

  2. Description of the Related Art Conventionally, in a multi-cylinder engine such as an automobile, an intake manifold is provided between an intake port of a cylinder head and a throttle valve that adjusts an intake air amount, and the intake air sucked into the intake manifold is divided to each intake air. Distribution to ports.

  With the recent increase in engine output, the intake manifold on-off valve is opened during high-speed or high-load operation to increase the flow rate of intake air supplied to the engine, and the intake manifold is opened and closed during low-speed or low-load operation. Variable intake devices that close valves are known.

  In this variable intake device, an openable / closable valve is provided in a collector to which intake air is supplied from the outside via a valve shaft, and the communication state of two volume chambers separated in the collector is switched by the open / close valve. It is possible. That is, the on-off valve closes the partition wall provided between the one volume chamber and the other volume chamber, so that the communication between the volume chambers is cut off, and the flow rate of the intake air supplied to the engine is reduced. On the other hand, when the on-off valve rotates via the valve shaft and is separated from the partition wall, the flow rate of the intake air supplied to the engine is increased through communication between the volume chambers (for example, Patent Documents). 1).

Japanese Patent Laid-Open No. 11-294172

  By the way, in a variable intake device having such an opening / closing valve, there is generally a slight gap between the opening / closing valve and the inner wall surface of the collector, and there is a problem that intake air leaks through this gap. . Therefore, when trying to suppress the leakage of intake air by reducing such a gap as much as possible, increase the processing accuracy of the inner wall surface of the on-off valve and collector and the assembly accuracy of the on-off valve and collector. However, this increases the manufacturing cost and manufacturing man-hour of the variable intake device. Even in this case, it is inevitable that a minute gap is formed between the on-off valve and the collector, and it is difficult to reliably prevent leakage of the intake air.

  Furthermore, in order to prevent leakage of the intake air, it is conceivable to apply a sealing agent to the inner wall surface of the collector to improve the sealing performance between the inner wall surface and the on-off valve. There is a problem that the application of the sealing agent to the wall surface is complicated.

  The present invention has been made in consideration of the above-mentioned problems, and is for an internal combustion engine that can further improve the airtightness when the passage length of the intake passage is switched by the passage length switching portion with a simple configuration. An object of the present invention is to provide an intake manifold device.

In order to achieve the above object, the present invention provides a long-pipe intake passage that is independently connected to each cylinder of a main body constituting an internal combustion engine and communicates with a chamber into which intake air is introduced from a throttle device. An intake manifold having a short pipe intake passage that branches off from a pipe intake passage and communicates with the chamber; and an intake manifold that is provided inside the intake manifold facing the intake passage, and that corresponds to the operating condition of the internal combustion engine. In an intake manifold device for an internal combustion engine comprising a passage length switching unit that switches a length,
The passage length switching unit includes a switching valve that is provided between the long pipe intake passage and the short pipe intake passage and is rotatably supported via a rotation shaft supported by the intake manifold,
The switching valve is formed in a plate shape whose one end is supported by the rotating shaft, and is formed of an elastic material on the side facing the inner wall surface of the intake passage, and is a seal member that can freely contact the inner wall surface Is provided.

  According to the present invention, the switching valve constituting the passage length switching unit is rotatably supported by the intake manifold via the rotating shaft connected to the one end side, and the side of the switching valve formed in the plate shape The part is provided with a seal member made of an elastic material so as to face the inner wall surface of the intake passage. When the long pipe intake passage and the short pipe intake passage are switched under the rotating action of the switching valve, the seal member abuts against the inner wall surface of the intake passage, so that the switching valve and the inner wall surface It is possible to prevent leakage of intake air through the gap. As a result, the air tightness in the intake passage when the long pipe intake passage and the short pipe intake passage are switched by the switching valve can be further improved, and a desired flow rate can be achieved through the long pipe intake passage or the short pipe intake passage. Intake air can be supplied to the engine.

  Further, since the seal member has a simple configuration in which it is mounted on the side portion of the switching valve facing the inner wall surface of the intake passage, the airtightness can be reliably and suitably held by the switching valve having this simple configuration. .

  Further, the seal member is provided so as to be displaceable with respect to the switching valve while being in contact with the inner wall surface of the intake passage, so that the switching valve including the seal member, the rotary shaft, the intake manifold, and the like are assembled. Even when the variation occurs, the seal member can be displaced so as to abut against the inner wall surface evenly under the abutting action with the inner wall surface. For this reason, the assembly variation when the passage length switching portion is assembled to the intake manifold is suitably absorbed, and the seal member can be reliably brought into contact with the inner wall surface of the intake passage. On the other hand, even when variations occur in the processing accuracy of the sealing member, the switching valve, the inner wall surface of the intake passage, etc., the variation is absorbed by the relative displacement of the sealing member with respect to the switching valve. The seal member can be brought into contact with the inner wall surface of the intake passage with certainty. Thereby, even when the assembly variation of the passage length switching part including the switching valve occurs, the airtightness in the intake passage is reliably maintained by the switching valve.

  Furthermore, by mounting the seal member so as to cover the side portion of the switching valve, the seal member reliably and preferably abuts against the inner wall surface of the intake passage, and the side portion is the inner wall surface of the intake passage. Therefore, it is possible to reliably prevent the intake air from leaking between the switching valve and the inner wall surface by the seal member.

  Still further, the seal member is attached to a groove portion provided on a side portion of the switching valve, and protrudes from the side portion toward the inner wall surface side, so that the seal member is surely and suitably applied to the inner wall surface of the intake passage. Since the sealing member can be formed smaller than the case where the sealing member is provided so as to cover the side portion of the switching valve, the switching including the sealing member can be performed. The weight of the valve can be reduced.

  According to the present invention, the following effects can be obtained.

  That is, when the long pipe intake passage and the short pipe intake passage are switched under the rotating action of the switching valve, the seal member provided on the side of the switching valve abuts against the inner wall surface of the intake passage. Leakage of the intake air through the switching valve and the inner wall surface is reliably prevented, and the airtightness in the intake passage can be further improved. It is possible to hold it.

  A preferred embodiment of an intake manifold device for an internal combustion engine according to the present invention will be described in detail below with reference to the accompanying drawings.

  In FIG. 1, reference numeral 10 indicates an intake manifold device for an internal combustion engine according to an embodiment of the present invention.

  An intake manifold device 10 for an internal combustion engine (hereinafter referred to as an intake manifold device 10) is provided in, for example, a four-cylinder engine 22 having four cylinder chambers mounted on a vehicle or the like.

  As shown in FIGS. 1 and 2, the intake manifold device 10 includes an intake manifold 14 having a plurality of branch pipes 12, and an intake passage through which intake air flows through the branch pipe 12 of the intake manifold 14. A path length switching unit 18 for switching the path length and a drive unit (not shown) for rotating and displace the path length switching unit 18 are provided.

  The intake manifold 14 is integrally formed, for example, by welding or bonding a plurality of divided bodies obtained by injection molding of a resin material. The intake manifold 14 has a chamber 20 in which air sucked through a throttle valve of a throttle device (not shown) is temporarily stored, and an intake passage connecting the chamber 20 and a cylinder head (main body portion) 24 of the engine 22. 16 and the like.

  The intake passage 16 is formed to have a substantially rectangular cross section, and a short pipe intake passage 26 that sucks intake air from the chamber 20 and supplies the intake air to the engine 22 when the engine 22 is operated at high speed or high load. During the low-speed or low-load operation, the long-pipe intake passage 28 that sucks the intake air from the chamber 20 and supplies the intake air to the engine 22, and the joint portion between the short-pipe intake passage 26 and the long-pipe intake passage 28. And a connecting passage 30 extending to the engine 22.

  The intake manifold 14 includes a mounting flange 32 connected to the cylinder head 24 of the engine 22, and the mounting flange 32 is coupled to the cylinder head 24 via a flat mounting surface. As a result, the intake passage 16 of the intake manifold 14 and the cylinder head 24 are connected and communicated with each other through the connection passage 30 penetrating through the mounting flange 32.

  The short pipe intake passage 26 is provided above the chamber 20, extends while curving toward the mounting flange 32, and has a lower end opened toward the chamber 20 side. On the other hand, the long pipe intake passage 28 opens at one end connected to the lower side of the chamber 20 and extends while curving along the outer wall surface of the intake manifold 14 from the one end toward the other end. . The other end of the long pipe intake passage 28 extends to above the short pipe intake passage 26, and the other end is connected to the short pipe intake passage 26. Thereby, the short pipe intake passage 26 and the long pipe intake passage 28 communicate with each other.

  The short pipe intake passage 26 is provided on the inner side with respect to the long pipe intake passage 28 formed in a curved shape along the outer wall surface of the intake manifold 14. It is set to be shorter than the passage length. That is, when the engine 22 is operating at high speed or high load, intake air is supplied to the cylinder head 24 constituting the engine 22 through the short pipe intake passage 26 having a short passage length, and when the engine 22 is operating at low speed or low load, The intake air is supplied to the cylinder head 24 through a long long pipe intake passage 28.

  Each of the short pipe intake passage 26 and the long pipe intake passage 28 is provided in accordance with the number of cylinders (for example, four) of the engine 22 (not shown), and the short pipe intake passage 26 and the long pipe intake passage 28 are provided. Are formed independently in parallel.

  On the other hand, a connecting portion 34 where the inner surfaces of the short pipe intake passage 26 and the long pipe intake passage 28 adjacent to each other are joined is provided at a joint portion between the short pipe intake passage 26 and the long pipe intake passage 28. A shaft (rotating shaft) 38 constituting the passage length switching unit 18 is rotatably supported by the connection unit 34 via a recess 36.

  As shown in FIGS. 3 to 5, the passage length switching unit 18 is provided at a joint portion between the short pipe intake passage 26 and the long pipe intake passage 28, and is a long shaft 38 that is pivotally supported by the intake manifold 14. And a plurality of valves 40 that are held by the shaft 38 and switch the flow state of the intake air in the intake passage 16.

  The shaft 38 is formed in a shaft shape having a constant diameter, and is provided with a plurality of shaft portions 42 supported by the intake manifold 14, and a plurality of mounting portions 44 provided between the shaft portions 42 to which the valves 40 are mounted. Have The shaft portion 42 is rotatably held at portions between the plurality of intake passages 16 in the intake manifold 14, and a driving portion (not shown) is connected to the end portion thereof.

  The attachment portions 44 are formed in a rectangular cross section, and are provided in a number corresponding to the number of the valves 40 (for example, four locations). The mounting portion 44 has a pair of mounting surfaces 44a spaced apart from each other by a predetermined distance about the axis of the shaft 38. The valve 40 is fixed to one of the mounting surfaces 44a formed in parallel to each other, and the mounting A set of screw holes 46 spaced apart from each other by a predetermined distance along the axial direction of the shaft 38 is formed in the surface 44a, and the screw holes 46 penetrate in a direction substantially orthogonal to the axis.

  The drive unit includes, for example, a stepping motor that is driven to rotate under energization. The rotation angle of the drive unit is a desired angle based on a control signal input from a controller (not shown) to the drive unit. Controlled. The shaft 38 including the shaft portion 42 and the mounting portion 44 is rotationally displaced by a predetermined angle under the driving action of a driving portion (not shown).

  The valve 40 is made of, for example, a plate body formed in a substantially rectangular shape, and includes a base body 48 made of a metal material and a seal member 50 that covers the outside of the base body 48. This valve 40 is provided in the connection part 34 which comprises the intake passage 16, and is arrange | positioned so that both sides may face inner wall surface (inner wall surface) 30a, 30b which isolate | separated the some branch pipe 12 mutually. (See FIG. 4).

  The base body 48 is formed of a plate material having a substantially constant thickness, and one end 48a is provided with a set of holes 52 spaced apart by a predetermined distance. The base body 48 is arranged so that one end 48 a having a hole 52 faces the screw hole 46 formed in the shaft 38, and the bolt 54 is screwed into the screw hole 46 through the hole 52. It is fixed to the mounting portion 44 of the shaft 38 (see FIG. 3). In this case, the valve 40 extends and is fixed so as to be orthogonal to the axial direction of the shaft 38.

  The seal member 50 is formed of an elastic material such as rubber, for example, and is mounted so as to cover the other end (side) 48b side of the base body 48. Specifically, the seal member 50 is provided with a substantially U-shaped cross section, and connects the first seal portion 50a attached to the other end portion 48b of the base body 48, and the other end portion 48b and the one end portion 48a. It is comprised from a pair of 2nd seal | sticker part 50b with which it installs so that both sides (side part) 48c may be covered. The seal member 50 is preferably formed of a material having a small coefficient of friction and a large elastic deformation, such as fluororubber or a silicone resin material.

  The first and second seal portions 50a and 50b have a recessed groove 56 that is open so as to face the base body 48. The recessed groove 56 includes the other end 48b of the base body 48, Both side portions 48c are inserted respectively. In other words, the seal member 50 is mounted so as to sandwich the other end portion 48b and both side portions 48c of the base body 48.

  As a result, the other end 48b and both side portions 48c of the base body 48 are covered by the sealing member 50 having a substantially U-shaped cross section. 48c increases by the thickness of the sealing member 50 (see FIG. 4), and the upper and lower surfaces of the base body 48 at the other end 48b and both side portions 48c are covered with the sealing member 50. Also, the thickness dimension increases (see FIG. 5).

  Since the seal member 50 is formed with a substantially constant thickness with the concave groove 56 as the center, the protruding amount with respect to the base body 48 is substantially constant.

  Further, when the seal member 50 is mounted on the base body 48, a clearance of a predetermined interval is provided between the concave groove 56 and the base body 48 (see FIG. 5). That is, the seal member 50 is provided to be displaceable by a predetermined distance along the width direction (arrow A direction) with respect to the base body 48.

  The valve 40 is disposed so that one end portion held by the shaft 38 inside the intake manifold 14 is disposed on the connection portion 34 side, and the other end portion provided with the seal member 50 faces the connection passage 30. (See FIGS. 1 and 2). When the valve 40 is rotationally displaced, the displacement is restricted by the other end portion coming into contact with the inner wall surface of the connection passage 30. As shown in FIG. 2, on the inner wall surface of the connection passage 30, a portion where the other end of the valve 40 contacts the connection passage 30 extending from the short pipe intake passage 26 is defined as a first contact portion 58. As shown in FIG. 6, a portion that contacts the connection passage 30 extending from the long pipe intake passage 28 is defined as a second contact portion 60.

  That is, the valve 40 is provided so as to be rotatable within a predetermined angle until the other end portion contacts the first and second contact portions 58 and 60 around the shaft 38.

  Further, the other end portion of the valve 40 abuts on the inner wall surface (second abutting portion 60) of the connection passage 30 extending from the long tube intake passage 28, whereby the short pipe intake constituting the intake passage 16. The long pipe intake passage 28 constituting the intake passage 16 is switched to the passage 26 and comes into contact with the inner wall surface (first contact portion 58) of the connection passage 30 extending from the short pipe intake passage 26. Switching to is performed.

  Then, when the valve 40 is rotationally displaced and the other end abuts on the first abutting portion 58 of the intake passage 16 via the seal member 50, the long pipe intake passage 28 and the connection passage 30 communicate with each other. In addition, the short pipe intake passage 26 is blocked, and the intake air of the chamber 20 is sucked into the engine 22 through the long pipe intake passage 28. Further, the other end portion of the valve 40 abuts on the second abutting portion 60 of the intake passage 16 extending from the long tube intake passage 28, whereby the short tube intake passage 26 and the connection passage 30 communicate with each other. In addition, the long pipe intake passage 28 is blocked, and the intake air of the chamber 20 is sucked into the engine 22 through the short pipe intake passage 26.

  In this case, the seal member 50 provided at the other end of the valve 40 is securely sealed by coming into contact with the inner wall surface of the intake passage 16, and the passage length of the intake passage 16 is increased by a long pipe intake by the valve 40. When switching to the passage 28 or the short pipe intake passage 26, leakage of the intake air from between the valve 40 and the valve 40 is prevented. Further, the second seal portion 50b of the seal member 50 provided on both sides of the valve 40 is brought into contact with the inner wall surfaces 30a and 30b of the intake passage 16, thereby ensuring airtightness when the valve 40 is rotated. When the other end of the valve 40 abuts against the inner wall surface of the intake passage 16 and is switched to the long-pipe intake passage 28 or the short-pipe intake passage 26, both sides of the valve 40 Leakage of intake air from between the inner wall surface is prevented.

  At this time, since the sealing member 50 of the valve 40 is formed of an elastic material such as rubber, the airtightness when the valve 40 comes into contact with the valve 40 is suitably maintained.

  The intake manifold device 10 for an internal combustion engine according to the embodiment of the present invention is basically configured as described above. Next, the operation and effects thereof will be described.

  For example, when the engine 22 is operating at a low speed or under a low load, the shaft 38 is urged counterclockwise (in the direction of arrow B) under the urging action of a resilient member such as a spring (not shown). Is in a state of abutting on the first abutting portion 58 of the connection passage 30 (see FIG. 2). That is, the long pipe intake passage 28 and the connection passage 30 constituting the intake passage 16 are connected by the other end of the valve 40 contacting the first contact portion 58 of the connection passage 30 via the seal member 50. Thus, the chamber 20 and the engine 22 communicate with each other via the long pipe intake passage 28.

  At this time, since the first seal portion 50 a constituting the seal member 50 is in contact with the inner wall surface (first contact portion 58) of the connection passage 30, the inner wall surface and the other end portion of the valve 40 are Since the leakage of the intake air through the gap is prevented, and the second seal portions 50b provided on both sides of the valve 40 are in contact with the inner wall surfaces 30a, 30b of the connection passage 30, Leakage of intake air from between both side portions of the valve 40 and the inner wall surfaces 30a, 30b is also prevented (see FIGS. 4 and 5). That is, the intake air in the chamber 20 does not flow to the connection passage 30 side through the short pipe intake passage 26, and the intake air flow through the short pipe intake passage 26 is reliably blocked by the valve 40. .

  As a result, the intake air from the chamber 20 is supplied to the cylinder head 24 of the engine 22 through the desired long pipe intake passage 28 and the connection passage 30.

  At this time, since the intake air is supplied from the chamber 20 to the engine 22 through the long pipe intake passage 28, the intake air per unit time taken into the engine 22 through the long pipe intake passage 28 having a long passage length is supplied. The flow rate is reduced.

  On the other hand, when the engine 22 is operating at a high speed or a high load, a control signal based on the engine speed or the like is output from a controller (not shown) to the drive unit, and the drive unit is an elastic force of a spring (not shown). As a result, the valve 40 is rotated clockwise (in the direction of arrow C) by a predetermined angle around the shaft 38 by being rotationally driven in the opposite direction. In this case, the second seal portion 50b of the seal member 50 attached to the valve 40 is displaced while being in sliding contact with the inner wall surfaces 30a and 30b of the connection passage 30.

  Then, the other end portion of the valve 40 abuts on the second abutment portion 60 of the connection passage 30 via the seal member 50, whereby the short pipe intake passage 26 and the connection passage 30 constituting the intake passage 16 are connected. Thus, the chamber 20 and the engine 22 communicate with each other via the short pipe intake passage 26. Note that the end of the long pipe intake passage 28 is closed by the valve 40, so that the flow of intake air through the long pipe intake passage 28 is blocked. As a result, the intake air from the chamber 20 is rapidly supplied to the cylinder head 24 of the engine 22 through the short pipe intake passage 26 and the connection passage 30 in a short time.

  At this time, since the first seal portion 50 a constituting the seal member 50 is in contact with the second contact portion 60 of the connection passage 30, the intake air passing between the inner wall surface and the other end portion of the valve 40. And the second seal portions 50b provided on both side portions of the valve 40 are in contact with the inner wall surfaces 30a and 30b of the connection passage 30. Leakage of intake air from between the inner wall surfaces 30a and 30b is also prevented. That is, the intake air in the chamber 20 does not flow to the connection passage 30 side through the long tube intake passage 28, and the intake air flow through the long tube intake passage 28 is reliably blocked by the valve 40. . As a result, the intake air from the chamber 20 is supplied to the cylinder head 24 of the engine 22 through the short pipe intake passage 26 and the connection passage 30.

  Thus, the intake air is supplied from the chamber 20 to the engine 22 through the short pipe intake passage 26 and the connection passage 30 of the intake passage 16 in a short time and in a large capacity.

  Thus, the flow rate and the inflow time of the intake air sucked into the engine 22 are suitably controlled under the switching action of the passage length switching unit 18 according to the operating state of the engine 22, and accordingly, the engine 22 The output can be improved.

  On the other hand, in the above description, the case where the seal member 50 is mounted so as to cover the other end portion 48b and both side portions 48c of the base body 48 constituting the valve 40 has been described, but is not limited thereto. For example, like the passage length switching unit 70 shown in FIGS. 7 and 8, the other end portion 64a and both side portions 64b of the base body 64 constituting the valve 62 are partially formed thick and provided therein. Alternatively, a sheet-like seal member 68 may be provided in the mounting groove (groove portion) 66. In other words, the sealing member 68 may be sandwiched between the other end portion 64a and both side portions 64b of the base body 64.

  The seal member 68 is formed in a substantially U shape having a constant thickness, and protrudes by a predetermined length from the other end portion 64 a and both side portions 64 b of the base body 64 in a state where the seal member 68 is mounted in the mounting groove 66. End portions of the seal member 68 are in contact with the first and second contact portions 58 and 60 in the connection passage 30 and are in contact with the inner wall surfaces 30 a and 30 b in the connection passage 30.

  Further, when the seal member 68 is mounted in the mounting groove 66, a clearance with a predetermined interval is provided between the sealing member 68 and the mounting groove 66. That is, the seal member 68 is provided to be displaceable along the width direction (arrow A direction) with respect to the base body 64.

  In the valve 62 having such a configuration, the seal member 68 made of an elastic material can be formed thinner than the seal member 50 according to the above-described embodiment, so that the weight related to the seal member 68 is reduced. In addition, the weight of the valve 62 can be reduced. As a result, the passage length switching unit 18 including the valve 62 can be driven more rapidly.

  As described above, in the present embodiment, the valve 40 constituting the passage length switching unit 18 is rotatably supported by the intake manifold 14 via the shaft 38 connected to the one end 48a side, and the valve A sealing member 50 made of an elastic material is provided so as to cover the other end portion 48b side and both side portions 48c of 40. When the long pipe intake passage 28 and the short pipe intake passage 26 are switched under the rotating action of the valve 40, the first seal portion 50a of the seal member 50 formed in a U-shaped cross section constitutes the intake passage 16. And abutting against the inner wall surfaces (first abutting portion 58, second abutting portion 60) of the connecting passage 30 and the second seal portion 50b against the inner wall surfaces 30a and 30b of the connecting passage 30, respectively. By abutting, leakage of intake air through the connection passage 30 and the valve 40 can be prevented. As a result, it is possible to improve the airtightness in the intake passage 16 when the long pipe intake passage 28 and the short pipe intake passage 26 are switched by the valve 40, and through the long pipe intake passage 28 or the short pipe intake passage 26. A desired flow rate of intake air can be supplied to the engine 22.

  Further, since the seal member 50 has a simple configuration in which the seal member 50 is attached to the other end portion 48b and both side portions 48c of the base body 48 constituting the valve 40 via the concave groove 56, the seal member 50 and the base The valve 40 including the body 48 can be easily assembled.

  Further, the seal member 50 is provided so as to be displaceable in the width direction (arrow A direction) with respect to the base body 48. Therefore, when an assembly error of the valve 40 with respect to the shaft 38 and an assembly error of the valve 40 with respect to the intake manifold 14 occur, the seal member 50 is displaced under the contact action with the inner wall surfaces 30a, 30b, and The positions are balanced so that the pressing forces on the inner wall surfaces 30a and 30b are substantially equal. Accordingly, by displacing the seal member 50 according to the assembly error, the seal member 50 can be reliably brought into contact with the inner wall surfaces 30a and 30b while suitably absorbing the assembly error. . As a result, even when an assembly error occurs between the intake manifold 14 and the valve 40, the airtightness by the valve 40 is reliably maintained.

  That is, when assembling the passage length switching unit 18 including the valve 40 to the intake manifold 14, the assembly efficiency of the intake manifold device 10 including the intake manifold 14 is improved without requiring high assembly accuracy. Can be made.

  Furthermore, even when the processing accuracy of the base body 48 to which the seal member 50 is attached varies, the seal member 50 is preferably relatively displaced with respect to the base body 48, and the inner wall surfaces 30 a and 30 b of the connection passage 30. Can be reliably and suitably brought into contact with each other. That is, the airtightness by the valve 40 can be maintained without increasing the processing accuracy of the base body 48. In other words, since high processing accuracy for the base body 48 is not required, the manufacturing cost of the base body 48 can be reduced.

  The intake manifold device for an internal combustion engine according to the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted without departing from the gist of the present invention.

1 is an overall longitudinal sectional view of an intake manifold device for an internal combustion engine according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view showing the vicinity of a passage length switching portion in the intake manifold device for an internal combustion engine of FIG. 1. FIG. 2 is a partially exploded external perspective view of a passage length switching unit constituting the intake manifold device for an internal combustion engine shown in FIG. 1. It is sectional drawing along the IV-IV line of FIG. It is sectional drawing along the VV line of FIG. FIG. 3 is an enlarged cross-sectional view showing a state where the passage length of the intake passage is switched by a passage length switching unit in the intake manifold device for the internal combustion engine of FIG. 2. It is a partially disassembled external appearance perspective view of the passage length switching part to which the valve concerning a modification is applied. It is a longitudinal cross-sectional view which shows the state in which the valve | bulb of FIG. 7 was provided in the intake manifold.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Intake manifold apparatus 12 ... Branch pipe 14 ... Intake manifold 16 ... Intake passage 18, 70 ... Passage length switching part 20 ... Chamber 26 ... Short pipe intake passage 28 ... Long pipe intake passage 30 ... Connection passage 34 ... Connection part 38 ... Shaft 40, 62 ... Valve 48, 64 ... Base body 50, 68 ... Seal member 50a ... First seal portion 50b ... Second seal portion 56 ... Concave groove 66 ... Mounting groove

Claims (4)

A long pipe intake passage that is independently connected to each cylinder of the main body constituting the internal combustion engine and communicates with a chamber into which intake air is introduced from a throttle device, and a short pipe that branches from the long pipe intake passage and communicates with the chamber. An internal combustion engine comprising: an intake manifold having a pipe intake passage; and a passage length switching portion that is provided inside the intake manifold facing the intake passage and switches a passage length of the intake passage according to an operating state of the internal combustion engine In the intake manifold system,
The passage length switching unit includes a switching valve that is provided between the long pipe intake passage and the short pipe intake passage and is rotatably supported via a rotation shaft supported by the intake manifold,
The switching valve is formed in a plate shape whose one end is supported by the rotating shaft, and is formed of an elastic material on the side facing the inner wall surface of the intake passage, and is a seal member that can freely contact the inner wall surface An intake manifold device for an internal combustion engine is provided. The apparatus of claim 1.
The intake manifold device for an internal combustion engine, wherein the seal member is provided so as to be displaceable with respect to the switching valve under a contact action with an inner wall surface of the intake passage. The apparatus according to claim 1 or 2,
The intake manifold device for an internal combustion engine, wherein the seal member is mounted so as to cover a side portion of the switching valve. The apparatus according to claim 1 or 2,
The intake manifold device for an internal combustion engine, wherein the seal member is mounted in a groove portion provided on a side portion of the switching valve and protrudes from the side portion toward the inner wall surface.

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