JP3874267B2 - Variable intake system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a variable intake device for an internal combustion engine (hereinafter, the internal combustion engine is referred to as an “engine”).
[0002]
[Prior art]
Conventionally, a variable intake device has been proposed in which the length of the intake passage is variably set in accordance with the engine speed to improve the engine torque. By increasing the length of the intake passage when the engine speed is low, and shortening the length of the intake passage when the engine speed is high, the torque can be improved regardless of the engine speed.
[0003]
In such a variable intake device, for example, intake passages having different passage lengths are branched and formed, and the intake passage is opened and closed by a valve member to change the overall length of the intake passage and the cross-sectional area of the intake passage. As a valve member that opens and closes the intake passage of the variable intake device, for example, a butterfly valve disclosed in DE 29916333U1 of Germany is known.
[0004]
[Problems to be solved by the invention]
As shown in FIG. 7, the variable intake device includes an intake manifold 100 that forms an intake passage. The intake manifold 100 branches according to the number of cylinders of the engine and forms an intake passage. A valve member is installed in each intake passage. The valve member is driven by a drive unit 102 having a motor 101, for example. A shaft 103 is installed on the valve member, and an end of the shaft 103 is inserted into a driving gear 104 to which a driving force from the driving unit 102 is transmitted. The drive gear 104 in which the shaft 103 is inserted is supported by the bearing 105 so as to be rotatable with respect to the intake manifold 100.
[0005]
In recent years, many of the members constituting the variable intake device such as the intake manifold 100 and the drive gear 104 are formed of, for example, a polyamide-based resin from the viewpoint of weight reduction, heat insulation, and improvement in design flexibility. On the other hand, the bearing 105 that supports the drive gear 104 is preferably made of metal in order to reduce sliding torque and improve the positional accuracy of the drive gear 104. Further, the bearing 105 needs to be fixed to the intake manifold 100 in order to prevent the drive gear 104 from moving in the axial direction. When the intake manifold is formed of metal as in the prior art, for example, the bearing is press-fitted into the intake manifold and fixed.
[0006]
However, when the intake manifold 100 is formed of resin as described above, even if a metal bearing 105 is press-fitted into the intake manifold 100, the clamping force decreases with the passage of time due to the creep of the resin, and the press-fitted state of the bearing 105 Is difficult to maintain. Therefore, looseness occurs between the intake manifold 100 and the bearing 105, and if an axial force is applied to the bearing 105, the bearing 105 may be detached from the intake manifold 100. As a result, the shaft 103 and the drive gear 104 can move in the axial direction together with the bearing 105. When an axial force is applied to the shaft 103, the drive gear 104 and the drive unit 102 may interfere with each other.
[0007]
Therefore, an object of the present invention is to provide a variable intake device that prevents the movement of a bearing member from an intake manifold.
[0008]
[Means for Solving the Problems]
According to the variable intake apparatus according to claim 1 Symbol placement of the present invention, a bearing member attached to the intake manifold is pressed against the intake manifold direction by the guide member. The guide member is pressed in the direction of the intake manifold by an attaching force when attaching the drive unit to the intake manifold. Therefore, the movement of the bearing member in the axial direction is limited by the guide member. Therefore, even when the intake manifold is formed of resin, the movement of the bearing member can be prevented.
[0009]
Furthermore, according to the variable intake device of the first aspect of the present invention, the gasket is installed between the intake manifold and the guide member and the drive unit. By attaching the drive to the intake manifold, the gasket is compressed. Therefore, the mounting force is transmitted to the guide member via the elastic force of the gasket, and the guide member presses the bearing member toward the intake manifold. Therefore, the movement of the bearing member in the axial direction is limited by the guide member. Therefore, the movement of the bearing member can be prevented.
[0010]
According to the variable intake device of the third aspect of the present invention, the drive gear sandwiches the bearing member and the guide member between the tooth portion and the protruding portion. Therefore, the relative movement between the bearing member and the drive gear is prevented, and the relative movement between the bearing member and the intake manifold is prevented by the guide member. Therefore, the movement of the bearing member with respect to the intake manifold can be prevented.
[0011]
According to the variable intake device of the fourth aspect of the present invention, the protrusion is a snap fit. Therefore, the drive gear and the bearing member are easily engaged. Therefore, the assembly of the variable intake device can be facilitated.
According to the variable intake device of the fifth aspect of the present invention, the guide member has the seal member in contact with the drive shaft member on the inner peripheral side. For this reason, it is possible to prevent the intake air flowing through the intake manifold from leaking to the drive unit side or the moisture contained in the intake air from entering the drive unit.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a plurality of examples showing embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
The variable intake system according to the first embodiment of the present invention is installed in an intake system of an engine. As shown in FIG. 2, the variable intake device 1 includes an intake manifold 10. The intake manifold 10 communicates the air connector 11 and the cylinder of the engine body 20.
[0013]
The intake air drawn from a suction duct (not shown) flows into the air connector 11 shown in FIG. 2 via an air cleaner and a throttle valve (not shown), and is distributed to the intake manifold 10 via a surge tank 10a. The intake manifold 10 branches from a surge tank 10a on the outlet side of the air connector 11 communicating with the outlet side of a throttle valve (not shown) corresponding to the number of cylinders of the engine body 20. The intake manifold 10 branched according to the number of cylinders further branches into a low-rotation intake passage 12 and a high-rotation intake passage 13. The low-rotation intake passage 12 is formed such that the entire length to the engine body 20 is longer than the high-rotation intake passage 13. The branched low-rotation intake passage 12 and high-rotation intake passage 13 merge again on the downstream side of the intake air flow, that is, on the engine body 20 side. A valve member 30 that opens and closes the flow of intake air in the intake passage 13 is installed in the intake passage 13 for high rotation. When the valve member 30 closes the intake passage 13, the intake air is supplied to the engine body 20 via the low-speed intake passage 12. On the other hand, when the valve member 30 opens the intake passage 13, the intake air is supplied to the engine body 20 via the high-rotation intake passage 13 having a smaller flow resistance. That is, by changing the flow rate of the intake air flowing through the intake passage 13, the overall length of the intake passage through which the intake air flows is changed.
[0014]
As shown in FIG. 3, the high-rotation intake passage 13 branches according to the number of cylinders of the engine body 20, and a valve member 30 is installed in each intake passage 13. The valve member 30 is provided with a shaft 40 as a drive shaft member extending therethrough. The shaft 40 is formed of a metal such as iron, for example, and has a polygonal cross section perpendicular to the axis. The valve member 30 includes a plate-like blade portion 31 and a cylindrical tube portion 32. The blade part 31 and the cylinder part 32 are integrally formed of, for example, a polyamide-based resin. A shaft hole 33 through which the shaft 40 passes is formed in the valve member 30. The shaft hole 33 is formed in substantially the same shape as the cross section of the polygonal shaft 40. Therefore, when the shaft 40 is inserted into the shaft hole 33, the relative rotation between the shaft 40 and the valve member 30 is limited.
[0015]
One end of the shaft 40 is rotatably supported by the intake manifold 10 by a bush 41. The intermediate portion of the shaft 40 is rotatably supported by the intake manifold 10 that forms the intake passage 13 via the guide bush 42.
A drive unit 50 that drives the valve member 30 is installed at the end of the shaft 40 on the side opposite to the bush. As shown in FIG. 1, the drive part 50 has the motor 52 accommodated in the housing 51, and the motor 52 is controlled by ECU which is not shown in figure. When the ECU interrupts energization of the motor 52, the valve member 30 is driven and the intake passage 13 is opened and closed. The driving force of the motor 52 is transmitted to the shaft 40 via a driving gear 60 installed at the end of the shaft 40 on the opposite bushing side. The drive unit 50 is fixed to the intake manifold 10 by a screw 53 or the like.
[0016]
The drive gear 60 has a tooth portion 61 and a cylindrical portion 62. The tooth part 61 and the cylinder part 62 are integrally formed, for example with the polyamide-type resin. The tooth portion 61 meshes with a pinion (not shown) attached to the motor 52. The cylindrical portion 62 is formed to protrude from the tooth portion 61 to the intake manifold 10 side, and has an insertion hole 63 into which the shaft 40 is inserted on the inner peripheral side. The insertion hole 63 is formed in the same shape as the section of the polygonal shaft 40 like the shaft hole 33. Therefore, the relative rotation between the drive gear 60 and the shaft 40 is limited by inserting the shaft 40 into the insertion hole 63. The cylindrical portion 62 is formed with a protruding portion 64 that protrudes radially outward. The protrusion 64 forms a snap fit that can be elastically deformed.
[0017]
The drive gear 60 into which the end of the shaft 40 opposite to the bush is inserted is supported by the bearing 14. As a result, the end of the shaft 40 on the side opposite to the bush is supported by the bearing 14 via the drive gear 60. The bearing 14 is a metal ball bearing and is accommodated in an accommodating portion 15 formed in the intake manifold 10. The accommodating portion 15 is formed to be slightly larger than the outer shape of the bearing 14. By supporting the drive gear 60 by the metal bearing 14, the sliding resistance accompanying the rotation of the drive gear 60 is reduced, and the positional accuracy of the drive gear 60 is increased.
[0018]
A guide member 70 is installed on the drive unit 50 side of the bearing 14. The guide member 70 is made of, for example, a polyamide-based resin. The guide member 70 is installed between the intake manifold 10 and the drive unit 50. A gasket 71 is installed between the intake manifold 10 and the guide member 70 and the drive unit 50. The gasket 71 is made of an elastic material such as rubber. The gasket 71 prevents intrusion of outside air from the contact portion between the housing 51 of the drive unit 50 and the intake manifold 10 to the intake passage 13 side.
[0019]
By attaching the drive unit 50 to the intake manifold 10, a force accompanying the attachment is applied between the drive unit 50 and the intake manifold 10. Due to the force accompanying this attachment, the gasket 71 is compressed. Therefore, a force that presses the bearing 14 toward the intake manifold 10 by the elastic force of the gasket 71 acts on the guide member 70. Thereby, the bearing 14 is pressed against the intake manifold 10 by the guide member 70, and the movement of the bearing 14 in the axial direction is limited.
[0020]
A seal member 72 is installed on the inner peripheral side of the guide member 70. The seal member 72 is formed of a flexible rubber or the like and is loosely adhered to the outer peripheral side of the cylindrical portion 62 of the drive gear 60. Thereby, the seal member 72 prevents the intake air from leaking from the intake passage 13 to the drive unit 50 side. Further, the seal member 72 prevents moisture contained in the intake air from entering the drive unit 50 side.
[0021]
Next, assembly of the variable intake device 1 having the above configuration will be described.
As shown in FIG. 4, the guide member 70 and the bearing 14 are attached to the outer peripheral side of the cylindrical portion 62 of the drive gear 60. The protrusion 64 of the drive gear 60 is a snap fit that engages with the end portion 14a of the bearing 14 on the side opposite to the drive portion. Therefore, by inserting the cylindrical portion 62 of the drive gear 60 on the inner peripheral side of the guide member 70 and the bearing 14, the projecting portion 64 is engaged with the end portion 14a of the bearing 14, and the guide member 70 and the bearing 14 are connected to the drive gear. It is sandwiched between the stepped portion 60 a formed on the tooth portion 61 of the 60 and the protruding portion 64. As a result, the guide member 70 and the bearing 14 are not detached from the drive gear 60.
[0022]
The assembled drive gear 60, guide member 70, and bearing 14 are attached to the intake manifold 10. By accommodating the bearing 14 in the accommodating portion 15 of the intake manifold 10, the assembled drive gear 60, guide member 70 and bearing 14 are positioned with respect to the intake manifold 10. Further, the shaft 40 is inserted into the insertion hole 63 of the drive gear 60.
[0023]
The gasket 71 is attached to the housing 51 of the drive unit 50. A motor 52 is accommodated in the housing 51 in advance. The drive unit 50 to which the gasket 71 is attached is attached to the intake manifold 10. The drive unit 50 is fixed to the intake manifold 10 by a screw 53. By attaching the drive unit 50 to the intake manifold 10, the gasket 71 is compressed, and the guide member 70 presses the bearing 14 toward the intake manifold 10 by the elastic force of the gasket 71. A stepped portion 70 a is formed on the drive unit 50 side of the guide member 70. Therefore, the drive unit 50 can be positioned by fitting the housing 52 of the drive unit 50 to the stepped portion 70 a of the guide member 70 together with the gasket 71.
[0024]
As described above, according to the first embodiment of the present invention described above, the guide member 70 presses the bearing 14 toward the intake manifold 10 by attaching the drive unit 50 to the intake manifold 10. Therefore, the bearing 14 is restricted from moving in the axial direction by the guide member 70. Therefore, even when the intake manifold 10 is formed of resin, the bearing 14 can be prevented from moving in the axial direction.
[0025]
Further, the guide member 70 and the bearing 14 are sandwiched between the stepped portion 60 a formed in the tooth portion 61 of the drive gear 60 and the protruding portion 64. Therefore, relative movement between the guide member 70 and the bearing 14 and the drive gear 60 is prevented. Thus, when the guide member 70 is installed between the drive unit 50 and the intake manifold 10, the drive gear 60 may be detached from the bearing 14 and the guide member 70 even if a force acts in the axial direction of the shaft 40. Absent. Further, the projecting portion 64 of the drive gear 60 is engaged with the end portion 14a of the bearing 14 on the counter drive portion side by a snap fit. Therefore, the guide member 70 and the bearing 14 and the drive gear 60 can be assembled only by inserting the cylindrical portion 62 of the drive gear 60 on the inner peripheral side of the guide member 70 and the bearing 14, and the assembly can be facilitated. .
[0026]
In the first embodiment, since the guide member 70 is made of resin, the degree of freedom in design is high. Therefore, by appropriately setting the shape of the guide member 70, the guide member 70 can limit the movement of the bearing 14 and can position the drive unit 50. Therefore, the positional accuracy of the drive unit 50, the drive gear 60, and the bearing 14 can be increased.
Furthermore, in the first embodiment, since the drive gear 60 is supported by the bearing 14, the sliding resistance is reduced, and the positional accuracy of the drive gear 60 at the support portion to the intake manifold 10 can be increased.
[0027]
(Modification)
A modification of the first embodiment will be described with reference to FIG.
In the modification, a pin member 65 is attached to the cylindrical portion 62 instead of forming a protruding portion on the cylindrical portion 62 of the drive gear 60. When the drive gear 60 is assembled with the guide member 70 and the bearing 14, the cylindrical portion 62 of the drive gear 60 is inserted into the inner peripheral side of the guide member 70 and the bearing 14. Then, a pin member 65 is attached to the cylindrical portion 62 protruding to the intake manifold 10 side of the bearing 14. The pin member 65 is attached to the cylindrical portion 62 by press-fitting or bonding, for example. As a result, the guide member 70 and the bearing 14 are sandwiched between the pin member 65 corresponding to the projecting portion and the stepped portion 60 a formed in the tooth portion 61.
[0028]
(Second embodiment)
A variable intake system according to a second embodiment of the present invention is shown in FIG. Components that are substantially the same as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
In the second embodiment, a seal member 80 is installed on the side opposite to the drive portion of the drive gear 60. The seal member 80 is formed of a flexible material such as rubber, and is loosely adhered to the shaft 40. Thereby, intrusion of intake air from the intake passage 13 to the drive unit 50 side is prevented. Further, since the seal member 80 is installed, the gap between the intake passage 13 and the drive unit 50 is blocked, so that the gasket and the seal member in the first embodiment can be omitted.
[0029]
On the other hand, in the case of the second embodiment, the force for pressing the guide member 70 against the bearing 14 is reduced by omitting the gasket in the first embodiment. Therefore, a flange 73 that expands radially outward is formed in the guide member 70, and the guide member 70 is sandwiched between the housing 51 of the drive unit 50 and the intake manifold 10. Thereby, the pressing force of the bearing 14 by the guide member 70 can be maintained.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a variable intake device according to a first embodiment of the present invention, and is a cross-sectional view showing the vicinity of a drive unit.
FIG. 2 is a schematic view showing an engine to which the variable intake device according to the first embodiment of the present invention is applied.
FIG. 3 is a schematic view showing a variable intake device according to a first embodiment of the present invention, and is a cross-sectional view showing a valve member, a drive unit and the like installed in an intake passage.
FIG. 4 is a schematic view showing a variable intake device according to the first embodiment of the present invention, and is a cross-sectional view in which the vicinity of a drive unit is exploded.
FIG. 5 is a schematic sectional view showing a modification of the variable intake device according to the first embodiment of the present invention.
FIG. 6 is a view showing a variable intake device according to a second embodiment of the present invention, and is a cross-sectional view showing the vicinity of a drive unit.
FIG. 7 is a view showing a conventional variable intake device, and is a cross-sectional view showing the vicinity of a drive unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Variable intake device 10 Intake manifold 13 Intake passage 14 Bearing (bearing member)
30 Valve member 40 Shaft (drive shaft member)
50 Drive part 60 Drive gear 61 Tooth part 62 Tube part 64 Projection part 65 Pin member (projection part)
70 Guide member 71 Gasket 72 Seal member

Claims (5)

A resin intake manifold that forms the intake passage;
A drive gear provided at an end of a drive shaft member for driving a valve member capable of changing an intake air amount flowing through the intake passage;
A bearing member attached to the intake manifold and rotatably supporting the drive gear on the intake manifold;
A drive unit that is attached to the intake manifold and drives the drive shaft member with the generated drive force via the drive gear;
A guide that is provided between the drive unit and the intake manifold, receives a force for attaching the drive unit to the intake manifold, presses the bearing member toward the intake manifold, and restricts movement of the bearing member in the axial direction. Members,
A gasket that is installed between the intake manifold and the guide member and the drive unit, seals between the intake manifold and the drive unit, and biases the guide member toward the bearing member by an elastic force; ,
A variable intake device comprising: The variable intake device according to claim 1 , wherein the drive gear includes a tooth portion that meshes with the drive portion and a cylindrical portion into which the drive shaft member is inserted . The cylindrical portion has a protrusion that can contact the bearing member and restricts movement of the drive gear in the axial direction, and the bearing member and the guide are between the tooth portion and the protrusion. The variable intake device according to claim 2 , wherein a member is sandwiched . The variable intake device according to claim 3 , wherein the protruding portion is a snap fit that engages with a side opposite to the driving portion of the bearing member . The guide member, the variable intake device of the inner peripheral side in any one claim of 4 claims 1, characterized in that it comprises a sealing member in contact with said drive shaft member.

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