JPH10280981A - Throttle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a throttle device which prevents an inner wall of a cylinder which surrounds a throttle valve during its connection time with a connecting tube, even when at least one connecting position of a throttle body and the connecting tube is deformed. SOLUTION: A thin-plate-shaped connecting part 14 of a throttle body 10 which is integratedly formed with resin connects a cylinder 11 which forms an intake path to a throttle part 13 with which a bolt contacts when the throttle body 10 is connected with an intake manifold. Even when the connecting plane of the throttle body 10 deforms toward opposite side of connection in integratedly forming process with resin, force which is impressed to the throttle part 13 from the bolt at the time when it is connected with the intake manifold is added to the connecting part 14 with low rigidity concentratively but is not added to the cylinder 11, and therefore, the intake path is prevented from deforming. This controls intake flow accurately and maintains smooth rotation of a throttle valve 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a throttle device for controlling an intake air flow rate.

[0002]

2. Description of the Related Art Conventionally, a connection portion of a throttle body connected to a connection tube such as an intake manifold, for example, a connection surface is not a flat surface but warps in a direction opposite to a connection side due to manufacturing distortion or the like. Is tightened with a bolt or the like, the tightening portion of the throttle body with which the bolt abuts is displaced toward the connection side by the tightening force of the bolt against the warpage of the connection surface. The displacement of the tightening portion of the throttle body that occurs when the throttle pipe is connected to the connection pipe also occurs when the connection location of the throttle body is not deformed and the connection location of the connection pipe is deformed.

When the force for displacing the tightening portion reaches the cylinder portion of the throttle body surrounding the throttle valve, the inner wall surface of the cylinder portion may be deformed. If the inner wall surface of the cylinder portion is deformed, the flow path area formed by the throttle valve and the inner wall surface of the cylinder portion cannot be set to a desired value according to the opening of the throttle valve, so that the intake flow rate cannot be controlled with high accuracy. Further, when the inner wall surface of the cylinder portion is deformed, the throttle valve and the inner wall surface of the cylinder portion come into contact with each other, which may hinder smooth rotation of the throttle valve.

[0004] In particular, when the throttle body is formed of resin for the purpose of reducing the weight, the connection portion with the connecting pipe is easily deformed when it is hardened. The walls are easily deformed.

[0005]

Problems to be Solved by the Invention
In the throttle device disclosed in Japanese Patent Laid-Open Publication No. 2 (1993) -1995, the strength of the cylinder is reinforced because the throttle body is formed of resin and the metal cylinder is disposed on the inner wall of the cylinder of the throttle body forming the intake passage. ing. However, when connecting the deformed throttle body to the connecting pipe, the throttle body is not configured to prevent a force from being applied to the cylindrical portion. Therefore, even if a metal cylindrical body is provided, the throttle body can be connected to the connecting pipe. At the time of connection, a force is applied to the cylindrical body to deform it, and the inner wall surface of the cylindrical part may be deformed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a throttle device for preventing an inner wall surface of a cylindrical portion surrounding a throttle valve from being deformed at the time of connection with a connection pipe even when at least one of connection points of a throttle body and a connection pipe is deformed. Is to provide.

[0007]

According to the throttle device of the first aspect of the present invention, a low-rigidity portion is provided between the cylindrical portion forming the intake passage and surrounding the throttle valve and the tightening portion with which the connecting means abuts. Because of the interposition, even if at least one of the connection points of the throttle body and the connection pipe is deformed, the force applied from the connection means to the tightening portion during connection is concentrated on the low rigidity portion, and the low rigidity portion is easily deformed. . Therefore, the force applied from the connecting means to the tightening portion is not applied to the cylindrical portion, thereby preventing deformation of the inner wall surface of the cylindrical portion. Thus, the flow passage area formed by the throttle valve and the inner wall of the cylinder can be maintained at a predetermined value according to the opening of the throttle valve, so that the intake air flow rate can be controlled with high accuracy. Further, the contact between the throttle valve and the inner wall of the cylinder can be prevented, and the smooth rotation of the throttle valve can be maintained.

In particular, when the throttle body is formed of resin, the connection portion of the throttle body is easily deformed.
It is effective to adopt the configuration described in claim 1. According to the throttle device of the second aspect of the present invention, since the low-rigidity portion is formed so as to extend in a plate shape in a direction orthogonal to the axis of the cylindrical portion, the tightening portion can be provided apart from the cylindrical portion. . Therefore, the force applied from the connecting means to the tightening portion is less likely to be applied to the cylindrical portion.

According to the throttle device of the third aspect of the present invention, since the low-rigidity portion is provided at a position away from the rotary shaft penetration portion of the throttle valve, the low rigidity portion is provided when the throttle body is connected to the connection pipe. The force that deforms the rigid part is less likely to be applied to the rotating shaft penetration part. Therefore, since the deformation of the rotation shaft insertion portion can be prevented, the throttle valve can smoothly rotate.

According to the throttle device of the present invention, the low-rigidity portion has a notch provided near the tightening portion of the throttle body, and the notch reduces the cross-sectional area of the member. The rigidity of the portion where the is formed becomes low.
Therefore, even if at least one of the connection points of the throttle body and the connection pipe is deformed, the force applied to the fastening portion from the connection means at the time of connection is concentrated on the portion where the notch is formed, and this portion is deformed. The force applied to the attached portion is absorbed by the portion where the notch is formed, and is not applied to the cylindrical portion. Therefore, deformation of the inner wall surface of the cylinder portion is prevented, and the flow path area formed by the throttle valve and the inner wall of the cylinder portion can be maintained at a predetermined value according to the opening degree of the throttle valve, so that the intake air flow rate can be controlled with high precision. Further, the contact between the throttle valve and the inner wall of the cylinder can be prevented, and the smooth rotation of the throttle valve can be maintained.

According to the throttle device of the fifth aspect of the present invention, since the tightening portion is formed to extend from the rotary shaft penetrating portion in a direction perpendicular to the rotary shaft of the throttle valve and the axis of the cylindrical portion, the rotary portion is formed. The mold for the throttle body can be removed in the opposite direction along the tightening portion from the shaft insertion portion.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIGS. 1, 2 and 3 show a throttle device according to a first embodiment of the present invention. The throttle body 10 of the throttle device 1 shown in FIGS. 1 and 2 has a cylindrical portion 11 forming an intake passage, and a rotary shaft penetrating a rotatable shaft 21 serving as a rotary shaft of a throttle valve 20 shown in FIG. It comprises an insertion portion 12, a fastening portion 13 with which a bolt 15 (FIG. 3) as a connecting means contacts, a connecting portion 14 as a low-rigidity portion, and the like, and is integrally formed of resin. FIG.
And the connecting part 14 shown in FIG. 2 is interposed between the fastening part 13 and the cylinder part 11 and connects the fastening part 13 and the cylinder part 11.
The connecting portion 14 is provided in a thin plate shape in a direction perpendicular to the axis of the cylindrical portion 11 at a position away from the rotary shaft insertion portion 12 in the axial direction of the cylindrical portion 11. The fastening portions 13 are independently arranged at four corners of the connecting portion 14.

The throttle valve 20 rotates together with the throttle shaft 21 to control the flow rate of the intake air flowing through an intake passage formed by the cylindrical portion 11 surrounding the throttle valve 20. An accelerator lever 30 is connected to one end of the throttle shaft 21. The accelerator lever 30 is connected to an accelerator operated by a driver via a wire (not shown). When the accelerator lever 30 rotates in accordance with the amount of depression of the accelerator, the throttle valve 20 and the throttle shaft 21 rotate to control the intake flow rate. The accelerator lever 30 is urged in the valve closing direction by the urging force of a spring 31. The fully closed position of the throttle valve 20 is defined by locking the stopper lever 32 attached to the accelerator lever 30 to the fully closed stopper 33. Since the fully closed stopper 33 is formed by a bolt, the fully closed position of the throttle valve 20 can be adjusted by changing the screwing amount of the bolt.

A rotation angle sensor 35 is attached to the other end of the throttle shaft 21. Rotation angle sensor 35
Is the rotation angle of the throttle shaft 21, that is, the throttle valve 2
An opening degree of 0 is detected, and an opening degree signal is transmitted from the connector 36 to an engine control device (not shown). Throttle body 1
0 is integrally molded with resin, so that when it is cured, the connection surface 10a warps in the opposite direction from the side where the amount of resin is large, that is, the side connected to the intake manifold 40 as a connection pipe as shown in FIG. The fastening part 13 has moved from the plane position to the non-connection side. The operation of the connecting portion 14 when connecting the thus deformed throttle body 10 to the intake manifold 40 will be described. The cross-sectional view of the throttle body 10 shown in FIG. 3 is a schematic cross-sectional view taken along the line III-III in FIG.

Since the intake manifold 40 is also formed of resin, the connection surface 40a of the intake manifold 40 also warps in the opposite direction from the connection side with the throttle body 10, as shown in FIG. Although not shown in FIG. 3, a gasket is provided between the throttle body 10 and the intake manifold 40. When the throttle body 10 and the intake manifold 40 are screwed together with the bolts 15 as connecting means in a state where the tightening portions are separated from the connection side in this way, the tightening portions 13 are tightened by the screw tightening force of the bolts 15. The fastening portion 41 is displaced toward the connection side and approaches each other. When the tightening portion 13 in contact with the bolt 15 is displaced to the connection side with the intake manifold 40, the screw tightening force received from the bolt 15 is formed in a thin plate shape and concentrates on the connecting portion 14 having low rigidity. The screw tightening force of the bolt 15 is not applied to the cylinder 11.

When the tightening portion 13 and the tightening portion 41 come closer to each other and come into contact with each other, the bolt tightening force of the bolt 15 is reduced.
Almost does not participate. In the first embodiment, since the connecting portion 14 formed in a thin plate shape is connected between the fastening portion 13 and the cylindrical portion 11 forming the intake passage, the connection portion between the throttle body 10 and the intake manifold 40 is not provided. Even if it is deformed at the time of molding, the bolt 1 applied to the tightening portion 13 at the time of connection
5 is concentrated on the connection portion 14 having low rigidity, and the connection portion 14 is easily deformed toward the connection side.
Is not applied to the cylindrical portion 11. Therefore, it is possible to prevent the inner wall surface of the cylindrical portion 11 from being deformed and the intake passage from being deformed. Accordingly, the flow passage area formed by the throttle valve 20 and the inner wall of the cylinder portion 11 can be maintained at a predetermined value according to the opening degree of the throttle valve 20, so that the intake flow rate can be controlled with high precision. Further, the contact between the throttle valve 20 and the inner wall of the cylindrical portion 11 is prevented, and the smooth rotation of the throttle valve 20 can be maintained.

Further, the thickness of a gasket disposed between the throttle body 10 and the intake manifold 40,
By adjusting the width and the like in accordance with the amount of deformation of the throttle body 10, the amount of displacement of the fastening portion 13 during connection can be reduced. (Modification) FIG. 4 shows a modification of the first embodiment. In the first embodiment, the connecting portion 14 is formed such that the connecting surface 10a is flat. However, the connecting surface with the connecting pipe may not be flat due to the configuration of the molding die and the shape of the throttle body. In the modified example, since the connecting portion 47 connecting the cylindrical portion 11 and the fastening portion 46 is formed in a thin plate shape by being recessed from the connection side, the connection surface of the throttle body 45 is uneven.

Even if the fastening portion 46 is warped in the opposite direction to the connection side during manufacturing, the force applied to the fastening portion 46 at the time of connection is concentrated on the connection portion 47 having low rigidity as in the first embodiment. Therefore, the force applied to the fastening portion 46 is not applied to the cylindrical portion 45. Therefore, it is possible to prevent the inner wall surface of the cylindrical portion 45 from being deformed and the intake passage from being deformed. As a result, the intake air flow rate can be controlled with high accuracy as in the first embodiment, and smooth rotation of the throttle valve can be maintained.

(Second Embodiment) FIG. 5 shows a second embodiment of the present invention.
And FIG. Components substantially the same as those in the first embodiment are denoted by the same reference numerals. The tightening portion 51 includes the rotating shaft insertion portion 12.
From the axis of the throttle shaft 21 and the cylinder 11. Tightening part 5 opposite to connection side
One end face 51a is formed to be flat. Therefore, even if the shape of the throttle body cannot be removed in the upstream direction of the intake of the throttle body, it can be removed in the direction of the arrow as in the throttle body 50 shown in FIG.

Further, since the fastening portions 51 are not formed independently at the four corners of the connecting portion 52 but are formed so as to extend from the rotary shaft insertion portion 12, the fastening portions 51 are formed when the throttle body 50 is formed. But it is hard to warp. In addition, the rotating shaft insertion portion 1
Since the rib 53 is formed on the connection side of the rotary shaft 2, even when a force applied to the tightening portion 51 when the throttle body 50 is connected to the intake manifold is applied to the rotary shaft penetrating portion 12, the rotary shaft penetrating portion 12 is not moved. Difficult to deform. Therefore, since the throttle shaft and the throttle valve can rotate smoothly,
The intake flow rate can be controlled with high accuracy.

(Third Embodiment) FIG. 7 shows a third embodiment of the present invention.
Shown in Components substantially the same as those in the first embodiment are denoted by the same reference numerals. The thickness of the tightening portion 61 and the connecting portion 62 for connecting the tightening portion 61 and the cylinder portion 11 are substantially equal, and the thickness is large enough to secure the strength enough to connect the throttle body 60 to the intake manifold with bolts or the like. That's fine. A notch 63 is formed in the connecting portion 62 near the fastening portion 61. The portion where the notch 63 is formed has a reduced cross-sectional area and reduced rigidity, and thus this portion forms a low-rigidity portion.

Even if the connection portion of the throttle body 60 connected to the intake manifold is deformed during molding,
Since the screw tightening force of the bolt applied to the tightening portion 61 is concentrated on the portion where the notch 63 having low rigidity is formed, the screw tightening force of the bolt is not applied to the cylindrical portion 11. Therefore, it is possible to prevent the inner wall surface of the cylindrical portion 11 from being deformed and the intake passage from being deformed. As a result, the intake air flow rate can be controlled with high precision, and smooth rotation of the throttle valve can be maintained.

In the above-described embodiments, when the throttle body is connected to the connection pipe, a connecting portion such as a bolt is in contact with the throttle body, and the cylinder portion 11 of the throttle body which forms the intake passage. The low rigidity portion is interposed between the fastening portion and the cylindrical portion 11 by a notch provided in a thin plate-like connection portion or a connection portion near the fastening portion.
Therefore, even when the connection portion of the throttle body with the connection pipe is deformed, the force applied to the tightening portion when connecting the throttle body to the connection pipe concentrates on the low-rigidity portion, so that the force is applied to the cylinder portion 11 surrounding the throttle valve 20. Since it is not added, it is possible to prevent the inner wall surface of the cylindrical portion 11 from being deformed. Accordingly, the flow passage area formed by the throttle valve 20 and the inner wall of the cylinder portion 11 can be maintained at a predetermined value according to the opening degree of the throttle valve 20, so that the intake flow rate can be controlled with high precision. Further, the contact between the throttle valve 20 and the inner wall of the cylindrical portion 11 is prevented, and the smooth rotation of the throttle valve 20 can be maintained.

As described above, the configuration in which the low-rigidity portion is provided between the throttle body and the tightening portion works effectively even when only the connection portion of the connection pipe is deformed instead of the throttle body. This prevents a force applied to the fastening portion from the connecting means such as the above from being applied to the cylindrical portion. Further, in the above embodiments, the resin inner wall of the cylindrical portion 11 directly forms the intake passage. However, a metal cylindrical body is insert-molded on the inner wall of the resinous cylindrical portion to reinforce the cylindrical portion, and the intake passage is formed. It is also possible to prevent deformation. Further, the throttle body may be formed of metal.

Further, instead of the bolt as the connecting means,
The connection pipe and the throttle body may be connected by being clamped by a clamp or the like.

[Brief description of the drawings]

FIG. 1 is a view of a throttle device according to a first embodiment of the present invention as viewed from an intake upstream side.

FIG. 2 is a view in the direction of arrow II in FIG. 1;

FIG. 3 is a schematic cross-sectional view showing a connection state between a throttle body and an intake manifold according to the first embodiment.

FIG. 4 is a schematic sectional view showing a modification of the first embodiment.

FIG. 5 is a view of a throttle device according to a second embodiment of the present invention as viewed from an intake upstream side.

6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is a view of a throttle device according to a third embodiment of the present invention as viewed from an intake upstream side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle device 10, 45, 50, 60 Throttle body 11 Cylindrical part 12 Rotation shaft penetration part 13, 46, 51, 61 Tightening part 14, 47, 52 Connection part (low rigid part) 15 Bolt (connection means) 20 Throttle valve 21 Throttle shaft (rotary shaft) 40 Intake manifold (connecting pipe) 63 Notch (low rigidity part)

Claims (5)

[Claims] 1. A throttle device comprising: a resin throttle body forming an intake passage; and a throttle valve rotatably housed in the throttle body and controlling an intake flow rate in the intake passage. The throttle body includes a tubular portion surrounding the throttle valve, a fastening portion in which connecting means for connecting the throttle body to a connection pipe abuts on the throttle body, and is interposed between the tubular portion and the fastening portion. A throttle device having a low rigidity portion. 2. The throttle device according to claim 1, wherein the low-rigidity portion extends in a plate shape in a direction orthogonal to an axis of the cylindrical portion. 3. The throttle device according to claim 1, wherein the low-rigidity portion is provided at a position separated from a rotation shaft insertion portion of the throttle valve formed on the throttle body. . 4. The throttle device according to claim 1, wherein the low rigidity portion has a notch provided near the fastening portion. 5. The tightening portion is formed to extend in a direction orthogonal to a rotation axis of the throttle valve and an axis of the cylinder portion from a rotation shaft insertion portion of the throttle valve formed in the throttle body. The throttle device according to any one of claims 1 to 4, characterized in that: