JP2013019513A - Valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-airtight valve device 6 despite of its simple structure.SOLUTION: In the valve device 6, an exhaust path 16 is formed of a tapered shape 16a in cross-section whose inner circumferential surface reduces along its given axial direction, and a center C2 of a valve body 14 and a rotational center C3 of a rotary shaft 13 are separated, while the rotational center C3 of the rotary shaft 13 is provided so as to intersect with a central axis 4C of the valve body. The valve body 14 includes an abutting portion 14a whose outer periphery is thin and is formed into a perfect circle. When the valve body 14 is allowed to make the transition to a closed state where a fluid passage is closed, the central axis 4C of the valve body 14 tilts at a given angle in relation to an axial direction C1 of the tapered shape 16a in cross-section, and thereby an entire circumference of the abutting portion 14a comes to contact with the tapered shape 16a in cross-section of a housing 12. On this occasion, when cutting the tapered shape 16a in cross-section of the housing 12 at a tilt angle of the valve body 14 at a position passing through the center C2 of the valve body 14, the cross-sectional shape created by the cutting exhibits a perfect circle.

Description

  The present invention relates to a valve device, a housing having a fluid passage formed therein, a rotating shaft rotatably supported by a bearing portion formed in the housing, and opening and closing the fluid passage fixed to the rotating shaft. The present invention relates to a valve device including a disc-shaped valve body.

Conventionally, a housing in which a fluid passage through which fluid flows is formed, a rotating shaft rotatably supported by a bearing portion formed in the housing, and the fluid passage fixed to the rotating shaft to open and close the fluid passage 2. Description of the Related Art A valve device including a disc-shaped valve body is known.
As such a valve device, there is known a valve device (Patent Document 1) in which the rotation center of the rotating shaft and the center of the valve body coincide with each other. In the case of such a valve device of Patent Document 1, When the valve body is in a closed state, there is a problem that fluid leaks from the bearing portion of the housing.
For such a valve device, the inner circumferential surface of the fluid passage has a tapered cross-section that reduces along the predetermined axial direction, and further, the rotation of the seal against the seal line that contacts the valve element and the tapered cross-section. A valve device in which the rotation center of a shaft is separated is known (Patent Document 2).
By setting it as such a structure, the said valve body can be located upstream from the said rotating shaft, and the problem that a fluid leaks from the bearing part of a housing can be solved.

JP 2004-263723 A Japanese Utility Model Publication No. 62-46863

In the above-mentioned Patent Document 2, as a conventional example, a configuration (FIG. 6) in which the rotation center of the rotary shaft is positioned on the central axis of the cross-section tapered shape of the fluid passage, and the rotation center of the rotary shaft from the central axis of the cross-section tapered shape And an eccentric configuration (FIG. 13).
However, when the center of rotation of the rotary shaft is positioned on the center axis of the tapered section of the fluid passage as in the configuration of FIG. 6, the outer periphery of the valve body is required to rotate the valve body to the closed state and the open state. It was necessary to greatly deform the resin-made seal member provided on the surface.
On the other hand, in the case of the configuration of FIG. 13, when the valve body is in the closed state, the pressure acts on the wide side of the valve body across the rotation center of the rotary shaft. There was a problem that the rotating shaft had to be rotated with high torque.
In view of such a problem, the present invention provides a highly airtight valve device with a simple configuration.

That is, the valve device according to the invention of claim 1 includes a housing in which a fluid passage through which a fluid flows is formed, a rotating shaft rotatably supported on a bearing portion formed in the housing, and the rotating shaft. A disc-shaped valve body that is fixed to and opens and closes the fluid passage,
In the valve device, the fluid passage has a tapered cross-sectional shape in which an inner peripheral surface is reduced along a predetermined axial direction, and the center of the valve body and the rotation center of the rotating shaft are separated from each other.
The valve body includes a contact portion formed in a perfect circle with a thin outer periphery,
The rotation center of the rotation shaft is provided so as to intersect with the central axis of the valve body that is orthogonal to the plane formed by the contact portion and passes through the center of the contact portion,
When the valve body is in a closed state in which the fluid passage is closed, the valve body central axis of the valve body is inclined at a predetermined angle with respect to the axial direction of the tapered section, and the entire circumference of the contact portion is In contact with the tapered cross-section of the housing,
At that time, if the tapered cross section of the housing is cut parallel to the inclination angle of the valve body at a position passing through the center of the valve body, the cross sectional shape becomes a perfect circle, and the cross sectional taper is formed at a position passing through the center of the valve body. When cut at an angle perpendicular to the axial direction of the shape, the cross-sectional shape does not become a perfect circle,
When the valve body is in the open state, the rotation shaft is set so that the angle between the valve body central axis of the valve body and the axial direction of the tapered section is larger than the inclination angle in the closed state. It is characterized by rotating.

According to the above invention, the contact portion of the valve body is a perfect circle, and when the valve body is in a closed state, the cross-sectional shape of the tapered section cut by the plane formed by the contact portion of the valve body is Since it becomes a perfect circle, the valve body and the taper shape of the cross section are in line contact with each other, so that high airtightness can be obtained and an elastically deformable seal member can be eliminated.
Further, since the rotation center of the rotary shaft is provided so as to intersect the valve body central axis of the valve body, when the valve body is closed, the pressure is applied to the valve body evenly across the rotation shaft. Can be.

The block diagram of the engine provided with the valve apparatus concerning a present Example Side view showing the configuration of the valve device Sectional drawing which shows arrangement of taper cross section of valve device, valve body, and rotation shaft The figure explaining the movement locus of the contact part of a valve element

FIG. 1 shows a configuration diagram of an automobile engine. FIG. 1 shows an engine 1 such as a diesel engine, an exhaust pipe 2 through which exhaust gas as fluid discharged from the engine 1 circulates, The exhaust pipe 2 includes first and second turbos 3 and 4 that are provided in series on the pipe line of the exhaust pipe 2, and a bypass passage 5 that bypasses the first turbo 3 is connected to the exhaust pipe 2. 5, a valve device 6 according to the present invention is provided.
The operating state of the first turbo 3 can be switched according to the operating state of the engine 1. Specifically, when the first turbo 3 is operated, the valve device 6 opens the bypass passage 5. When the first turbo 3 is closed and the first turbo 3 is deactivated, the valve device 6 is opened and exhaust gas is supplied from the bypass passage 5 to the second turbo 4.

FIG. 2 is a block diagram of the valve device 6. The valve device 6 is rotatably supported by a housing 12 having an exhaust passage 11 through which exhaust gas flows and a bearing portion (not shown) formed in the housing 12. A rotary shaft 13, a disc-like valve body 14 that is fixed to the rotary shaft 13 and opens and closes the exhaust passage 11, and a driving means 15 that drives the rotary shaft 13.
The housing 12 is inserted in the middle of the bypass passage 5, and a metal ring-shaped member 16 is fixed inside, and the inner peripheral surface of the ring-shaped member 16 has a tapered cross section 16 a that forms the exhaust passage 11. Has been processed.
The housing 12 and the ring-shaped member 16 are provided with the bearing portion in the left-right direction in the drawing, and the rotary shaft 13 is rotatably supported by the bearing portion via a sealing means (not shown) and rotates. One end of the shaft 13 protrudes outside the housing 12 and is connected to the driving means 15.
Further, the disc-shaped valve body 14 is fixed to the rotary shaft 13, and when the valve body 14 is closed as will be described in detail later, the outer periphery of the valve body 14 and the ring-shaped member 16 The exhaust passage 11 is closed by making line contact with the tapered section 16a.
The driving means 15 includes a servo motor 17 fixed to the upper portion of the housing 12, an arm 18 rotated by the servo motor 17, and a link 19 provided between the arm 18 and the rotating shaft 13. Has been.
With the configuration described above, the servo motor 17 rotates the rotary shaft 13 so that the valve body 14 fixed to the rotary shaft 13 is switched between a closed state and an open state.

Next, with reference to FIG. 3, the cross-sectional taper shape 16 a that forms the exhaust passage 11 formed on the inner peripheral surface of the ring-shaped member 16 that constitutes the exhaust passage 11, the rotating shaft 13, and the valve body 14 will be described in detail. explain. 3 shows a closed state in which the valve body 14 closes the exhaust passage 11, and the exhaust gas flows from the left to the right in the drawing.
First, the ring-shaped member 16 is formed of metal, and the cross-sectional taper shape 16a formed on the inner peripheral surface of the ring-shaped member 16 extends along the axial direction C1 of the cross-sectional taper shape 16a set in the horizontal direction in the drawing. It is processed so as to shrink from the downstream side in the flow direction toward the upstream side. The cross-sectional shape at each position of the cross-sectional taper shape 16a will be described in detail later.
Next, the rotary shaft 13 is fixed to one surface of the valve body 14, and the center C2 of the valve body 14 and the rotational center C3 of the rotary shaft 13 are separated from each other. It is located on the downstream side of the exhaust gas with respect to the valve body 14 in the closed state.
The rotary shaft 13 may be provided on the upstream side of the exhaust gas with respect to the valve body 14, but from the viewpoint of ensuring the sealing performance between the rotary shaft 13 and the bearing portion, the rotary shaft 13 is provided on the downstream side of the exhaust gas. It is desirable to provide it.
The valve body 14 is integrally formed of metal, and a thin contact portion 14a is formed on the outer peripheral portion thereof. The contact portion 14a is formed in a perfect circle.
Here, in the present embodiment, the center C2 of the valve body and the center of the contact portion 14a coincide with each other, and are orthogonal to the plane formed by the contact portion 14a, and the center C2 of the valve body 14 The axis passing through is called the valve body central axis C4.
The positional relationship between the valve body 14 and the rotary shaft 13 will be described in more detail. The rotation center C3 of the rotary shaft 13 intersects with the valve body central axis C4. In other words, the rotary shaft 13 Is provided in the center of the valve body 14.
The rotation center C3 of the rotary shaft 13 passes through the vicinity of the center of the cross-sectional taper shape 16a, and does not need to coincide with the center accurately.

As shown in FIG. 3, when the valve body 14 is closed, the valve body central shaft 4C is inclined at a predetermined angle with respect to the axial direction C1 of the tapered section 16a. In the example, the rotating shaft 13 is in a closed state in a state where it is rotated counterclockwise by an angle θ.
When the valve body 14 is in the closed state in this way, the entire circumference of the contact portion 14a of the valve body 14 comes into line contact with the tapered section 16a of the ring-shaped member 16 constituting the fluid passage 11, and the exhaust passage 11 Is supposed to be closed.
In other words, in this closed state, the tapered section 16a is cut along the plane formed by the contact portion 14a, in other words, cut parallel to the inclination angle θ of the valve body 14 at a position passing through the center C2 of the valve body 14. Then, the cross-sectional shape becomes a perfect circle having the same diameter as the contact portion 14 a of the valve body 14.
On the other hand, when the cross-sectional taper shape 16a is cut by a plane perpendicular to the axial direction C1 of the cross-section taper shape 16a at a position passing through the center C2 of the valve body 14, the cross-sectional shape does not become a perfect circle but is substantially oval. It becomes a shape.
Then, the cross-sectional taper shape 16a of the ring-shaped member 16 is obtained by enlarging and reducing the non-circular shape obtained by cutting the cross-sectional taper shape 16a in a direction perpendicular to the axial direction C1 of the cross-sectional taper shape 16a. It has been formed.

FIG. 4 shows an enlarged view of the cross-section taper shape 16a of the ring-shaped member 16 and the contact portion 14a of the valve body 14, and the valve body 14 is opened from the closed state. The figure explaining the locus | trajectory of the said contact part 14a in becoming is shown.
As described above, the rotary shaft 13 of the present embodiment is fixed to one surface of the valve body 14, and the center C2 of the valve body 14 and the rotation center C3 of the rotary shaft 13 are separated from each other. The contact portion does not rotate at the center C2 of the valve body 14, but rotates around the rotation center C3 of the rotating shaft 13.
For this reason, in order to change the valve body 14 from the closed state to the open state, the angle between the valve body central axis 4C of the valve body 14 and the axial direction C1 of the tapered section 16a is inclined more than the angle θ in the closed state. Thus, in other words, it is necessary to rotate in the counterclockwise direction in FIG.
Then, the contact part 14a shown in the upper and lower parts in the drawing is separated from the tapered section 16a, and then the valve body 14 is opened to a predetermined opening degree by the driving means 15.
On the contrary, even if the valve body 14 is rotated from the closed state to an angle smaller than the angle θ in the closed state, in other words, the clockwise direction in FIG. As is apparent, the corresponding contact portion 14a interferes with the tapered cross section 16a, and the valve body 14 cannot be rotated and the closed state is maintained.

As described above, in the valve device 6 of this embodiment, the center C2 of the valve body 14 and the rotation center C3 of the rotary shaft 13 are separated from each other, and the rotary shaft 13 is downstream of the valve body 14 in the exhaust gas flow direction. On the side.
For this reason, when the valve body 14 is in a closed state, the exhaust gas is prevented from flowing by the valve body 14, so that the exhaust gas has the rotating shaft 13 and the bearing portion of the housing 12 that supports the rotating shaft 13. It is designed not to leak from between.
Further, when the contact portion 14a of the valve body 14 is thin and has a perfect circle, the valve body central axis 4C of the valve body 14 is predetermined with respect to the axial direction C1 of the tapered section 16a. Inclined at an angle, the contact portion 14a of the valve body 14 and the tapered section 16a come into line contact, and the exhaust passage 11 can be closed with high airtightness.
That is, in the closed state, when the cross-sectional taper shape 16a is cut along a plane formed by the contact portion 14a of the valve body 14, the cross-sectional shape becomes a perfect circle having the same diameter as the contact portion 14a.
Then, the rotation center C3 of the rotary shaft 13 is provided so as to intersect the valve body central axis 4C of the contact portion 14a of the valve body 14, so that the valve body 14 in the closed state is placed on the rotary shaft 13. , The valve body 14 in line contact can be detached from the tapered cross-section 16a.
That is, the valve body 14 according to the present embodiment does not require an elastically deformable resin sealing member mounted on the valve body 14 disclosed in Patent Document 2, and does not cause a problem of deterioration due to deformation of the sealing member. .
Furthermore, the exhaust passage 11 can be closed by metal touch by forming the valve body 14 and the ring-shaped member 16 having the tapered section 16a formed of metal.
The valve body 14 is provided so as to intersect with the valve body central axis 4C of the contact portion 14a of the valve body 14, thereby balancing the pressure acting on the both sides of the valve body 14 with the rotary shaft 13 therebetween. be able to.

6 Valve device 11 Exhaust passage 12 Housing 13 Rotating shaft 14 Valve body 14a Contact portion 16a Cross section taper shape C1 Axis direction of taper section C2 Center of valve body C3 Center of rotation of rotation shaft C4 Valve body center axis

Claims (3)

A housing formed with a fluid passage through which a fluid flows, a rotary shaft rotatably supported by a bearing portion formed in the housing, and a disk shape fixed to the rotary shaft to open and close the fluid passage With a valve body,
In the valve device, the fluid passage has a tapered cross-sectional shape in which an inner peripheral surface is reduced along a predetermined axial direction, and the center of the valve body and the rotation center of the rotating shaft are separated from each other.
The valve body includes a contact portion formed in a perfect circle with a thin outer periphery,
The rotation center of the rotation shaft is provided so as to intersect with the central axis of the valve body that is orthogonal to the plane formed by the contact portion and passes through the center of the contact portion,
In a state where the valve body closes the fluid passage, the valve body central axis of the valve body is inclined at a predetermined angle with respect to the axial direction of the tapered section, and the entire circumference of the contact portion is the fluid. In contact with the tapered cross-section of the passage,
At that time, when the cross-sectional taper shape of the housing is cut by a plane formed by the contact portion, the cross-sectional shape becomes a perfect circle,
When the valve body is in the open state, the rotation shaft is set so that the angle between the valve body central axis of the valve body and the axial direction of the tapered section is larger than the inclination angle in the closed state. A valve device characterized by rotating.   The valve device according to claim 1, wherein the valve body is integrally formed of metal, and the contact portion is made of metal.   The valve device according to claim 2, wherein the housing is formed of metal, and the valve body and the cross-sectional tapered shape of the inner peripheral surface of the housing are metal touched.

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