JP2011069482A - Valve device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an EGR valve suppressing pressure loss on a fully opening side to the minimum. <P>SOLUTION: This valve device reduces resistance in an EGR flow passage 1 on the fully opening to the minimum and achieves an ultralow pressure loss by dividing a shaft 4 in the EGR flow passage and forming three of parts, namely, a disc valve 7, a first valve supporting part 8, and a second valve supporting part 9, into a substantially U-shape by press-molding them to reduce thickness of a valve body 3 greatly. Since the valve body 3 is formed by press-molding, the cost of the valve body 3 is suppressed to the minimum. This valve device absorbs reduction of precision by virtue of the press-molded valve body 3, and prevents EGR gas from leaking when closing the valve without fail by supporting a valve seat ring 12 owing to spring action of a bellows 14 and three thin wall swelling parts to displace in the three-dimensional omnidirection and by aligning the disc valve 7 with a tapered face formed on the valve seat ring 12. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a butterfly-type valve device that opens and closes a fluid passage or changes the passage area of a fluid passage by rotating a valve body, for example, discharged from an engine (an internal combustion engine that generates power by burning fuel). The present invention relates to a technique suitable for use in an EGR valve or the like for returning a part of exhaust gas to an intake passage.

  A butterfly type valve device includes a shaft disposed so as to vertically traverse a fluid passage formed in a housing (valve housing), and a valve body having a disk shape fixed to the shaft in the fluid passage. The valve body is rotated in the fluid passage by rotating the shaft from the outside of the housing, and the opening and closing of the fluid passage or the passage area of the fluid passage is varied (for example, Patent Documents 1 to 3). 3).

  However, since the conventional butterfly type valve device has a structure in which the shaft passes through the fluid passage so as to cross the fluid passage, the shaft is fluid on the side where the valve body opens the fluid passage greatly (hereinafter, fully open side). The ratio of blocking the passage (area ratio occupied by the shaft in the fluid passage as seen from the fluid flow direction) increases. For this reason, the conventional butterfly type valve device has a problem that the shaft in the fluid passage causes an increase in pressure loss on the fully open side.

Japanese Patent Laid-Open No. 08-170735 JP 2008-057431 A JP 2009-036108 A

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a valve device capable of suppressing pressure loss on the fully open side in a type in which a shaft is disposed perpendicular to the center line of a fluid passage. Is in the provision of.

[Means of Claim 1]
In the valve device according to the first aspect, the center line of the fluid passage and the center line of the shaft are arranged vertically.
The shaft includes a first shaft to which a driving force is applied and a second shaft disposed on the central axis of the first shaft, and the first shaft and the second shaft are rotatably supported with respect to the housing. In addition, the first shaft and the second shaft are disposed in a state of being separated inside the fluid passage.
The valve body includes a disc valve capable of closing the fluid passage, a first valve support provided on the outer peripheral side of the disc valve and connecting the disc valve and the first shaft, and the first valve support. And a second valve support portion that is provided on the outer peripheral side of the disc valve on a side different from the portion and connects the disc valve and the second shaft, and when viewed from the direction along the plate surface, The first and second valve support portions are provided so as to form a substantially U shape.

By being provided in this way, on the fully opened side, (i) the ratio of the shaft closing the fluid passage can be suppressed, and (ii) the valve body is formed in a substantially U shape when viewed from the fluid flow direction. The ratio at which the valve body blocks the fluid passage can be kept small.
Thus, the valve device adopting the means of claim 1 is a type in which the shaft is arranged perpendicular to the center line of the fluid passage, but the ratio of the shaft and the valve body closing the fluid passage on the fully open side is set. Since it can be made small, the pressure loss of the valve device can be kept low, and a large amount of fluid can flow on the fully open side. Alternatively, since the pressure loss on the fully open side can be kept low, the valve device can be downsized.

[Means of claim 2]
The three members of the disc valve and the first and second valve support portions in the valve device of the means of claim 2 are integrally provided by press molding of a metal plate.
In this way, the valve body can be made extremely thin by providing the three members of the disc valve, the first and second valve support portions, which constitute the valve body, by the press-molded product of the metal plate. Loss can be extremely small.
Moreover, since the valve body can be provided as a press-molded product, the cost of the valve body can be kept low, and the cost of the valve device can be kept down.

Further, the valve device of the means of claim 2 has a valve seat ring that abuts the outer peripheral portion of the disc valve when the valve body closes the fluid passage and closes the gap between the fluid passage and the disc valve. The valve seat surface on which the disc valve abuts on the valve seat ring is provided on a tapered surface that expands in a curved or linear manner in the direction in which the disc valve is arranged. It has been.
The valve seat part can displace the valve seat ring in all radial directions of the fluid passage, and a flow direction displacement support means (for example, a bellows described later) that supports the valve seat ring so as to be displaceable in the flow direction of the fluid passage. And a radial displacement support means (for example, three or more thin-walled bulges described later).
Accordingly, (i) the valve seat ring is supported by the flow direction displacement support means and the radial direction displacement support means so as to be displaceable in all three dimensions, and (ii) the disc valve is seated on the valve seat when the valve is closed. Due to the aligning effect generated by sitting on the surface (tapered surface), it is possible to absorb a decrease in accuracy caused by providing the valve body with a press-molded product.
That is, even if the valve body is provided as a press-molded product, seal leakage at the time of closing the valve can be prevented.

[Means of claim 3]
The first and second shafts in the valve device of the means of claim 3 contact the valve seat ring when the disc valve opens the fluid passage, and press the valve seat ring away from the disc valve. A shaft cam portion to be moved is formed.
As a result, when the first and second shafts are rotated and the disk valve opens the fluid passage, the valve seat ring is rotated by the action of the shaft cam portion accompanying the rotation of the first and second shafts. Moving to the side away from the valve, a gap is formed between the valve seat ring and the disc valve.
Thus, when the disc valve opens the fluid passage, a clearance is formed between the valve seat ring and the disc valve, so that contact wear between the valve seat ring and the disc valve can be avoided. Since the contact resistance between the valve seat ring and the disc valve is suppressed, the torque required for the rotation of the disc valve (first and second shafts) can be reduced (for example, the electric actuator can be reduced in size). ).
Further, the valve seat ring and the disc valve are forcibly separated when the valve is opened, so that a problem that the valve main body is closed and locked can be avoided, and the reliability of the valve device can be improved.

[Means of claim 4]
The flow direction displacement support means in the valve device of the means of claim 4 is a bellows arranged on the fluid upstream side of the disc valve.
The bellows includes an annular engagement portion that engages with a step formed on the inner wall of the fluid passage on the fluid upstream side, and the bellows bellows portion and the valve seat ring are disposed on the fluid downstream side of the annular engagement portion. Is done.
The bellows has a pressure canceling structure in which the pressure applied to the inside and the pressure applied to the outside cancel each other, but the unevenness of the bellows is affected by the flow of the fluid. As a result, (i) the annular engaging portion is pressed against the step, and the sealing performance between the annular engaging portion and the step is slightly enhanced. (Ii) the valve seat ring is pressed against the disc valve side. Thus, the effect of slightly improving the sealing performance between the disc valve and the valve seat ring is obtained.
On the other hand, apart from the pressure canceling structure by the bellows, (i) by securing a pressure receiving surface of the fluid in the annular engagement portion, the annular engagement portion is pressed against the step by the influence of the fluid pressure, and the annular engagement portion and The effect of improving the sealing performance between the steps is obtained, and (ii) by securing a fluid pressure receiving surface on the valve seat ring, the valve seat ring is pressed to the disc valve side by the influence of the fluid pressure, The effect | action which improves the sealing performance of a plate valve and a valve seat ring is acquired.
That is, it is possible to obtain a self-seal using a fluid flow and pressure.

[Means of claim 5]
The radial displacement support means in the valve device of the means of claim 5 is provided by three or more thin bulges provided on the outer peripheral side of the valve seat ring, and the valve is operated by the spring action of the thin bulges. A seat ring is supported displaceably in all radial directions of the fluid passage.
Thus, since the valve seat ring is supported through three or more thin bulges, the vibration resistance of the valve seat ring can be improved.

[Means of claim 6]
The valve seat component in the valve device according to the sixth aspect is provided as a single component by a resin material {for example, Teflon (registered trademark)} having a smooth surface.
Thereby, the contact resistance between the valve main body and the valve seat ring can be lowered. Further, in the case of adopting the above third aspect, the contact resistance between the shaft cam portion and the valve seat ring can be lowered.
As described above, since the contact resistance with respect to the valve seat ring can be reduced, the torque required for the rotation of the disc valve (first and second shafts) can be reduced (for example, the electric actuator can be downsized). it can).

In addition, since the problem of deposits and other impurities adhering to the valve seat surface is suppressed, an increase in rotational resistance of the valve body due to deposits and other impurities can be suppressed. As a result, a disc valve ( Torque required for rotation of the first and second shafts can be reduced (for example, the electric actuator can be reduced in size).
Similarly, by suppressing the adhesion of moisture due to the flooding effect on the seat surface of the valve seat, an increase in the rotational resistance of the valve body caused by freezing of the adhered moisture can be suppressed. As a result, the disc valve Torque required for rotation of the (first and second shafts) can be reduced (for example, the electric actuator can be reduced in size).

[Means of Claim 7]
In the valve device according to the seventh aspect of the present invention, the valve side contact portion that contacts the valve seat ring in the disc valve is provided in a spherical shape.
As a result, in the range in which the disc valve rotates in contact with the valve seat ring, the disc valve can smoothly rotate, and the torque required to rotate the disc valve (first and second shafts) is reduced. (For example, the electric actuator can be reduced in size).
Further, the contact area between the disc valve and the valve seat ring when the valve is closed increases, and wear of the contact portion between the disc valve and the valve seat ring can be suppressed.

[Means of Claim 8]
In the valve device according to the eighth aspect, the outer peripheral tip of the disc valve provided on the outer periphery further than the valve-side contact portion is provided in a knife edge shape over the entire periphery.
By providing in this way, the influence which a disc valve receives from a fluid at the time of valve opening can be made small. As a result, the torque required to rotate the disc valves (first and second shafts) in the valve open state can be reduced (for example, the electric actuator can be reduced in size).

[Means of Claim 9]
The valve device of the means of claim 9 performs the two functions of "flow direction displacement support means" and "radial direction displacement support means" of claim 2 described above with one "radial direction bellows diaphragm". is there.
Specifically, the means of claim 9 is the same as that of claim 2 above, in which the three members of the disc valve and the first and second valve support parts are integrally provided by press molding of a metal plate, The valve body can be made extremely thin by providing three members, the disc valve constituting the valve body, and the first and second valve support parts, by a metal plate press-molded product, and the pressure loss on the fully open side is extremely small. can do.
Moreover, since the valve body can be provided as a press-molded product, the cost of the valve body can be kept low, and the cost of the valve device can be kept down.

Further, the valve device of the means of claim 9 is in contact with the outer peripheral portion of the disc valve when the valve body closes the fluid passage, as in the above-mentioned claim 2, so that the gap between the fluid passage and the disc valve is reduced. A valve seat part having a valve seat ring to be closed is provided, and a valve seat surface on which the disc valve abuts in the valve seat ring is curved or linear in a direction in which the disc valve is arranged. It is provided on the tapered surface that expands in diameter.
The valve seat part of the means of claim 9 is provided with a “radial bellows diaphragm” in place of the “flow direction displacement support means” and “radial direction displacement support means” of claim 2. This radial bellows diaphragm is provided on the outer diameter side of the valve seat ring, forms a bellows part that can be elastically deformed in the radial direction, and displaces the valve seat ring in the flow direction of the fluid passage and in all the radial directions of the fluid passage. It is possible to support.
The valve ring is supported by the radial bellows diaphragm so as to be displaceable in all three dimensions. When the valve is closed, the disc valve is seated on the valve seat surface (tapered surface), so that the valve seat ring can be aligned with the disc valve.
As a result, it is possible to absorb a decrease in accuracy caused by providing the valve body with a press-formed product. That is, even if the valve body is provided as a press-molded product, seal leakage at the time of closing the valve can be prevented.

[Means of Claim 10]
The means of claim 10 includes “flow direction thrust means” as means for bringing the valve seat ring supported in the radial direction by the radial bellows diaphragm into contact with the disc valve.
This flow direction thrust means is a means for pressing the valve seat ring against the disc valve at least when the valve is closed by shifting the end of the valve seat ring on the fluid downstream side to the fluid downstream side.
Thus, since the valve seat ring is provided so as to be in pressure contact with the disc valve by the flow direction thrust means, as described in the above-mentioned claim 9, when the valve is closed, the disc valve has a valve seat surface (tapered surface). ), And the valve seat ring can be aligned with the disc valve.

[Means of Claim 11]
The means of claim 11 is the same technology as that of claim 3 above, and the first and second shafts contact the valve seat ring when the disc valve opens the fluid passage, and the valve seat ring is A shaft cam portion that is pressed and moved to the side away from the plate valve is formed.
Thus, as in the third aspect, when the first and second shafts are rotated and the disc valve opens the fluid passage, the shaft cam portion is acted upon by the rotation of the first and second shafts. The valve seat ring moves away from the disc valve, and a gap is formed between the valve seat ring and the disc valve.
Thus, when the disc valve opens the fluid passage, a clearance is formed between the valve seat ring and the disc valve, so that contact wear between the valve seat ring and the disc valve can be avoided. Since the contact resistance between the valve seat ring and the disc valve is suppressed, the torque required for the rotation of the disc valve (first and second shafts) can be reduced (for example, the electric actuator can be reduced in size). ).
Further, the valve seat ring and the disc valve are forcibly separated when the valve is opened, so that a problem that the valve main body is closed and locked can be avoided, and the reliability of the valve device can be improved.

FIG. 4 is a schematic cross-sectional view of the EGR valve viewed from the flow direction of the EGR gas when fully opened, and a schematic cross-sectional view of the EGR valve viewed from the side surface when fully closed (Example 1). It is the front view which looked at the valve-seat component from the flow direction of the fluid, and side sectional drawing (Example 1). (Example 1) which is an operation | movement explanatory drawing of the EGR valve | bulb at the time of a fully-closed and half-opening. FIG. 4 is a cross-sectional view taken along line A in FIG. 3B, and is a cross-sectional view showing a cam shape of a shaft cam portion (Example 1). It is sectional drawing which follows the B line of Fig.3 (a), and is a principal part enlarged view shown in the circle C, Comprising: It is explanatory drawing of the knife edge shape provided in the outer periphery front-end | tip of a disc valve (Example 1). FIG. 5 is a schematic cross-sectional view of the EGR valve viewed from the flow direction of the EGR gas when fully opened, and a schematic cross-sectional view of the EGR valve viewed from the side surface when fully closed (Example 2). (Example 2) which is principal part sectional drawing of valve seat components. (Example 2) which is the operation | movement explanatory drawing of the EGR valve | bulb at the time of full closing and half open. FIG. 9 is a cross-sectional view taken along line D in FIG. 8B, and is a cross-sectional view showing a cam shape of a shaft cam portion (Example 2). (Example 3) which is principal part sectional drawing of valve seat components. (Example 4) which is principal part sectional drawing of valve seat components. (Example 5) which is an exploded view which shows the assembly before an EGR valve | bulb. It is an assembly completion figure which shows after the assembly of an EGR valve | bulb, and sectional drawing which follows the EE line | wire of Fig.13 (a) (Example 5).

[Description of Embodiments] [Mode for carrying out the invention] will be described with reference to the drawings.
○ An EGR valve (an example of a valve device) includes an EGR flow path 1 (an example of a fluid path) that communicates an exhaust passage and an intake passage of an engine and through which exhaust gas can pass, and an EGR flow A valve body 3 that is disposed in the passage 1 and that opens and closes and adjusts the opening of the EGR passage 1 (variation of the passage area) by being rotationally displaced inside the EGR passage 1 and is rotatably supported by the housing 2. And a shaft 4 that rotationally drives the valve body 3, and the center line of the EGR flow path 1 and the center line of the shaft 4 are arranged vertically. That is, this EGR valve is a type in which the shaft 4 vertically crosses the EGR flow path 1.

The shaft 4 in this EGR valve is composed of a first shaft 5 to which a driving force in the rotational direction is applied from the outside and a second shaft 6 disposed on the central axis of the first shaft 5. The shaft 5 and the second shaft 6 are arranged in a state of being separated inside the EGR flow path 1.
On the other hand, the valve main body 3 in the EGR valve has a disk shape 7 that is disk-shaped and can close the EGR flow path 1, and is provided on the outer peripheral side of the disk valve 7. A first valve support portion 8 for connecting the shaft 5 and a first valve support portion 8 provided on the outer peripheral side of the disc valve 7 on a side different from the first valve support portion 8 to connect the disc valve 7 and the second shaft 6. And a two-valve support portion 9, viewed from the direction along the plate surface of the disc valve 7 (viewed from the direction in which the EGR gas flows when fully opened), the disc valve 7, the first and second valve supports. The three parts 8 and 9 form a substantially U shape.

Next, a first embodiment in which the present invention is applied to an EGR valve of an EGR device mounted on a vehicle engine will be described with reference to FIGS. In the present embodiment, the same reference numerals as those in the [DETAILED DESCRIPTION OF THE INVENTION] denote the same functional objects.
[Description of EGR device]
The EGR device returns part of the exhaust gas discharged from the engine to the intake side of the engine as EGR gas, thereby mixing EGR gas, which is non-combustible gas, into part of the intake air to suppress the combustion temperature of the engine combustion chamber, This is a well-known technique that effectively suppresses the generation of nitrogen oxides (NOx).
The EGR device includes at least an EGR passage 1 for returning a part of the exhaust gas flowing through the exhaust passage to the intake passage, and an EGR valve for adjusting the opening degree of the EGR passage 1, and the EGR valve is in a running state of the vehicle. Accordingly, the opening degree is controlled by an ECU (abbreviation of engine control unit).

  The EGR valve to which the present invention is applied may be a high pressure EGR valve mounted on a high pressure EGR device that returns EGR gas to a high negative pressure generation range in the intake passage (intake downstream of the throttle valve). It may be a low-pressure EGR valve mounted on a low-pressure EGR device that returns EGR gas to a low negative pressure generation range in the intake passage (intake upstream of the throttle valve: for example, upstream of intake of the compressor in a turbocharged vehicle). .

Next, the EGR valve will be described with reference to FIG. In the following description, the upper side in FIG. 1 is referred to as the upper side, and the lower side in the figure is referred to as the lower side. However, the upper and lower directions are directions for explaining the embodiment and are not limited.
The EGR valve includes a housing 2 that forms an EGR flow path 1 therein, a valve main body 3 disposed in the EGR flow path 1, a shaft 4 that supports the valve main body 3, and a shaft 4 from the outside of the housing 2. And an electric actuator 10 for applying a rotational force to the motor.

The main part of the housing 2 is made of an aluminum alloy die-cast, and the inner wall of the EGR passage 1 through which high-temperature EGR gas flows is provided by a member (for example, stainless steel) having excellent heat resistance and corrosion resistance. .
The valve body 3 is a butterfly valve, can open and close the EGR flow path 1 according to the rotational position of the shaft 4, can change the opening area of the EGR flow path 1, and the opening area of the EGR flow path 1 Is adjusted to adjust the amount of EGR returned to the intake passage. Details of the valve body 3 will be described later.

The shaft 4 rotatably supports the valve body 3 in the EGR flow path 1, and is rotatably supported by bearings 11 disposed above and below the EGR flow path 1. Details of the shaft 4 will be described later. The bearing 11 is a shield type that prevents leakage of EGR gas.
The upper and lower bearings 11 are ball bearings, rolling bearings such as roller bearings, or sliding bearings such as metal bearings. The upper and lower bearings 11 are fixed inside the bearing housing cylinder formed in the housing 2 by a coupling means such as press fitting, The shaft 4 inserted through is supported rotatably.

The electric actuator 10 is fixed to the upper portion of the housing 2 and rotationally drives the shaft 4 and is equipped with a known electric motor that generates rotational power when energized. As an example of the electric motor, a DC motor capable of controlling the rotation angle by energization is used.
Here, the electric actuator 10 may be provided only by the electric motor (that directly drives the shaft 4 by the output shaft of the electric motor), or a speed reduction mechanism (electric motor) is provided between the electric motor and the shaft 4. And the rotational torque increased by the deceleration may be transmitted to the shaft 4, for example, a gear reduction mechanism may be interposed.

[Background Art 1 of Example 1]
In the EGR valve of the first embodiment, as shown in FIG. 1B, the center line of the EGR flow path 1 and the center line of the shaft 4 that drives the valve body 3 are arranged vertically.
As described above, when the shaft 4 is disposed vertically with respect to the EGR flow path 1, the conventional EGR valve has a structure in which the shaft 4 is disposed so as to cross the EGR flow path 1. In this case, the ratio that the shaft 4 blocks the EGR flow path 1 is increased, and there is a problem that the amount of EGR on the fully open side decreases due to an increase in ventilation resistance.

[Feature Technology 1 of Example 1]
The first embodiment employs the following technique in order to solve the problem of the “background art 1”.
A shaft 4 that supports the valve body 3 is disposed on a first shaft 5 to which a driving force in a rotational direction is applied by an electric actuator 10 disposed on an upper portion of the housing 2, and a central axis of the first shaft 5. As shown in FIG. 1, the first shaft 5 and the second shaft 6 are arranged in a state separated from each other inside the EGR flow path 1.

  The first shaft 5 has a cylindrical bar shape made of a member (for example, stainless steel) having excellent heat resistance and corrosion resistance, and is arranged extending in the vertical direction on the upper side of the housing 2. The bearing 11 is rotatably supported. The lower end of the first shaft 5 is a thinned first step as a connecting means for connecting to the upper portion of the valve body 3 (specifically, a first valve support portion 8 described later) so as to rotate integrally. 1 Two-sided width 5a is provided.

Similarly to the first shaft 5, the second shaft 6 also has a cylindrical rod shape made of a member having excellent heat resistance and corrosion resistance (for example, stainless steel), and extends in the vertical direction below the housing 2. It is arranged and is rotatably supported by a bearing 11 attached to the housing 2. The upper end of the second shaft 6 also has a narrowed first step as a connecting means for connecting so as to rotate integrally with the lower portion of the valve body 3 (specifically, a second valve support portion 9 described later). 2 A width across flats 6a is provided.
The shaft cam portion 16 provided on the first and second shafts 5 and 6 will be described later.

  The valve body 3 is provided between the first and second shafts 5 and 6, and is a disc valve 7 capable of opening and closing the EGR flow path 1, and the first shaft 5 above the disc valve 7. 1 and a second valve support 9 connected to the upper end of the second shaft 6 at the lower portion of the disc valve 7, as shown in FIG. When viewed from the direction along the plate surface of the disc valve 7, the disc valve 7, the first and second valve support portions 8, 9 form a substantially U shape.

The disc valve 7 is a disc body having a small thickness, and is arranged perpendicular to the center line of the EGR channel 1 as shown in FIG. 1B, thereby closing the EGR channel 1. Is.
The first valve support portion 8 is a plate material having a small thickness dimension provided continuously with the end portion of the disc valve 7 and integrated with the disc valve 7, and the plate surface of the first valve support portion 8 is the disc valve. 7 is provided so as to extend in the vertical direction. The first valve support 8 is connected to rotate integrally with the lower end of the first shaft 5, and the first valve support 8 is connected to rotate integrally with the lower end of the first shaft 5. As a means, a substantially oval first through hole 8a is formed which fits with the first double width 5a formed at the lower end of the first shaft 5.

  The second valve support portion 9 has a thickness dimension provided integrally with the disc valve 7 continuously with the disc valve 7 at the end of the disc valve 7 on the side different from the first valve support portion 8. It is a small plate material, provided so that the plate surface of the second valve support portion 9 faces the first valve support portion 8 and the plate surface of the second valve support portion 9 extends perpendicularly to the disc valve 7. ing. The second valve support portion 9 is connected to rotate integrally with the upper end of the second shaft 6, and the second valve support portion 9 is connected to rotate integrally with the upper end of the second shaft 6. As a means, a substantially oval second through hole 9a is formed which is fitted to a second width across flat 6a formed at the upper end of the second shaft 6.

  The first two-surface width 5a and the first through-hole 8a, and the second two-surface width 6a and the second through-hole 9a are, after press-fitting (or loose fitting), when assembling the EGR valve, It is welded and fixed.

(Effect 1 of Example 1)
In the first embodiment, by adopting the above-described feature technique 1, since the shaft 4 is divided in the EGR flow path 1 on the fully open side (including the full open) of the EGR valve, the EGR flow path (Ii) The valve body 3 is provided in a substantially U shape when viewed from the flow direction of the EGR gas, and the valve body 3 has a substantially U shape. By providing the thin plate valve 7 and the first and second valve support portions 8 and 9 with a small thickness, the ratio of the valve main body 3 closing the opening area of the EGR flow path 1 can be extremely reduced. Thereby, the flow resistance in the EGR flow path 1 on the fully open side of the EGR valve can be made extremely small, and the pressure loss of the EGR valve on the fully open side can be made extremely small.
That is, the EGR valve can be reduced in pressure loss, and a large amount of EGR gas can flow on the fully opened side. Alternatively, since the EGR gas can flow in a large amount on the fully open side, the EGR valve can be downsized.

[Feature Technology 2 of Example 1]
The valve body 3 according to the first embodiment includes a substantially U-shaped disk valve 7 and first and second valve support portions 8 and 9 formed by pressing (punching and bending) a thin metal plate (for example, a stainless steel thin plate). The valve body 3 is provided by a metal plate press-molded product.
Thus, the valve body 3 can be made extremely thin by providing the disc valve 7 and the first and second valve support portions 8 and 9 constituting the valve body 3 with a metal plate press-molded product. The pressure loss on the side can be made extremely small.
Further, by providing the valve body 3 as a press-molded product, the cost of the valve body 3 can be kept low, and as a result, the cost of the EGR valve can be kept down.

[Feature Technology 3 of Example 1]
The EGR valve according to the first embodiment has a valve seat ring 12 (seal that prevents EGR gas leakage by contacting the outer peripheral portion of the disc valve 7 when the valve is closed (when the valve body 3 closes the EGR flow path 1). A valve seat part 13 having a ring) is provided.
As shown in FIG. 1B, the valve seat surface 12a (valve seating surface) with which the disc valve 7 abuts in the valve seat ring 12 is the direction in which the disc valve 7 is disposed (downstream direction of the EGR gas flow). ) Is provided on a tapered surface that linearly increases in diameter.

  On the other hand, the valve seat part 13 includes (i) a flow direction displacement support means (specifically) that supports the valve seat ring 12 so as to be displaceable in the EGR gas flow direction in the EGR flow path 1 as shown in FIG. (Ii) as shown in FIG. 2, and (ii) a radial direction that supports the valve seat ring 12 so as to be displaceable in all radial directions of the EGR flow path 1. Displacement support means 15 (specifically, three thin bulging portions 15a are provided as will be described later) is provided.

Thereby, (i) the valve seat ring 12 is displaced in all three-dimensional directions (all directions of the X-axis, Y-axis and Z-axis indicating three dimensions) by the flow direction displacement support means (bellows 14) and the radial direction displacement support means 15. (Ii) caused by providing the valve body 3 as a press-molded product by a centering action caused by the disc valve 7 being seated on the tapered surface of the valve seat surface 12a when the valve is closed. The decrease in accuracy can be absorbed.
That is, even if the valve body 3 is provided as a press-molded product, it is possible to avoid a problem that EGR gas leaks in the EGR valve when the valve is closed, and the reliability can be improved.

[Feature Technique 4 of Example 1]
As shown in FIG. 3, the first and second shafts 5 and 6 in the first embodiment contact the valve seat ring 12 when the disc valve 7 opens the EGR flow path 1, and this valve seat ring A shaft cam portion 16 is formed to press and move 12 to the side away from the disc valve 7.
The shaft cam portion 16 is provided on the first and second shafts 5 and 6 that are opposed to the valve seat ring 12. Specifically, the shaft cam portion 16 is for the shaft cam portion 16 to move the valve seat ring 12 to the upstream side in a range from the opening degree at which the valve body 3 opens the EGR flow path 1 to a predetermined opening degree. The relationship between the opening degree of the disc valve 7 and the moving distance by which the valve seat ring 12 is moved to the upstream side of the EGR gas is shown in FIGS. 4 (a) and 4 (b). It is determined by 16 shapes (cam profile).

As described above, when the first and second shafts 5 and 6 are provided with the shaft cam portions 16, the first and second shafts 5 and 6 rotate and the disc valve 7 opens the EGR flow path 1. In addition, the valve cam ring 16 moves to the side away from the disc valve 7 by the action of the shaft cam portion 16 accompanying the rotation of the first and second shafts 5 and 6 {the arrow F in FIG. 3 (b '). Reference}, a gap is formed between the valve seat ring 12 and the disc valve 7.
Thus, when the disc valve 7 opens the EGR flow path 1, a clearance is formed between the valve seat ring 12 and the disc valve 7, thereby causing contact wear between the disc valve 7 and the valve seat ring 12. In addition, the contact resistance between the disc valve 7 and the valve seat ring 12 can be suppressed, so that the torque required to rotate the first shaft 5 to drive the disc valve 7 can be reduced. The electric actuator 10 can be downsized.
Further, when the valve seat ring 12 and the disc valve 7 are forcibly separated when the valve is opened, it is possible to avoid a problem that the valve main body 3 is closed and to improve the reliability of the EGR valve. .

[Feature Technology 5 of Example 1]
The first embodiment uses a bellows 14 as a flow direction displacement support means. The bellows 14 is a bellows-shaped flexible pipe that is disposed on the upstream side of the EGR gas flow from the disc valve 7 and is provided integrally with the valve seat ring 12.
On the upstream side of the EGR gas flow of the bellows 14, as shown in FIG. 3A, a step 1a formed on the inner wall of the EGR flow path 1 existing in the housing 2 (toward the upstream side of the EGR gas flow). And an annular engagement portion 14a that engages with the step 1a, so that the annular engagement portion 14a is seated on the step 1a. A structure in which the gap is sealed is adopted.

The bellows 14 has a pressure canceling structure (see range α in FIG. 3A) in which the pressure applied to the inside and the pressure applied to the outside cancel each other. However, the unevenness of the bellows 14 affects the influence of the flow of EGR gas. receive.
As a result, (i) the annular engagement portion 14a is pressed against the step 1a, and the sealing performance between the annular engagement portion 14a and the step 1a is slightly enhanced. (Ii) The valve seat ring 12 is a disc. When pressed against the valve 7 side, the sealing performance between the disc valve 7 and the valve seat ring 12 is slightly enhanced.
On the other hand, apart from the pressure canceling structure by the bellows 14, (i) by securing the fluid pressure receiving surface {refer to the range β in FIG. 3A} in the annular engagement portion 14a, the annular engagement is caused by the influence of the EGR gas pressure. The joint portion 14a is pressed against the step 1a, and the sealing performance between the annular engagement portion 14a and the step 1a can be enhanced.
Alternatively, (ii) by securing a fluid pressure-receiving surface {see the range γ in FIG. 3A) on the valve seat ring 12, the valve seat ring 12 is pressed against the disc valve 7 side due to the influence of the EGR gas pressure. Thus, the sealing performance between the disc valve 7 and the valve seat ring 12 can be enhanced.
Thus, by adopting a self-sealing utilizing the flow and pressure of EGR gas, it is possible to eliminate the problem of EGR gas leaking in the EGR valve when the valve is closed, and to improve reliability.

[Feature Technology 6 of Example 1]
As shown in FIG. 2, the radial displacement support means 15 in the first embodiment is provided by three thin bulging portions 15 a arranged at substantially equal intervals on the outer peripheral side of the valve seat ring 12. As shown in FIG. 2A, each thin-walled bulging portion 15a is punched out with a knife shape inside the bulging portion that bulges in an arc shape in the radial direction, and the thickness (the thickness in the radial direction and the thickness in the fluid flow direction). Both) are made thin by providing spring properties. Then, by inserting and arranging the valve seat ring 12 at a predetermined assembly position in the EGR flow path 1, the three thin bulges 15 a are assembled in a state where they are slightly elastically deformed inward by the inner wall of the EGR flow path 1. The valve seat ring 12 is supported so as to be displaceable in all radial directions of the EGR flow path 1 by the spring action of the thin bulging portion 15a.
Thus, since the valve seat ring 12 is supported on the inside of the inner wall of the EGR channel 1 via the three thin bulges 15a, the vibration resistance of the valve seat ring 12 can be improved. The valve opening due to vibration (the leakage of EGR gas when the valve is closed) can be prevented.

[Feature Technique 7 of Example 1]
The valve seat component 13 of the first embodiment is provided as a single component by a resin material having a smooth surface (for example, Teflon (registered trademark), nylon resin having excellent heat resistance, etc.). That is, the valve seat ring 12 including the three thin bulge portions 15a and the bellows 14 including the annular engagement portion 14a are integrally provided by one resin material.
Thus, by providing the valve seat part 13 with a resin material having a smooth surface, the contact resistance between the valve body 3 and the valve seat ring 12 can be lowered, and the shaft cam portion 16 and the valve seat ring 12 The contact resistance can be reduced, and the electric actuator 10 can be reduced in size.

Moreover, the malfunction that a deposit adheres to the valve seat sheet surface 12a is suppressed. As a result, an increase in the rotational resistance of the valve main body 3 due to the adhesion of the deposit and the valve closing adhesion of the valve main body 3 can be suppressed, and the electric actuator 10 can be reduced in size.
Alternatively, since water droplets are prevented from adhering to the valve seat surface 12a, an increase in rotational resistance of the valve body 3 caused by freezing of the adhering water droplets can be suppressed, and the electric actuator 10 can be downsized. Can do.

[Feature Technique 8 of Example 1]
In the disk valve 7 of the first embodiment, a valve-side contact portion 7a (a portion seated on the valve seat surface 12a) that contacts the valve seat ring 12 when the valve is closed is provided in a spherical shape.
As a result, the drive torque of the disc valve 7 can be reduced in the range in which the disc valve 7 rotates in contact with the valve seat ring 12 (the range of rotation slightly opened from the closed state to the valve opening side). The actuator 10 can be reduced in size.
Moreover, the contact area of the disc valve 7 and the valve seat ring 12 at the time of valve closing becomes large, and the contact wear of the disc valve 7 and the valve seat surface 12a can be suppressed.

[Feature Technology 9 of Example 1]
As shown in FIG. 5 (b), the disc valve 7 of the first embodiment has a knife edge shape (knife blade) with an outer peripheral tip 7b existing further on the outer periphery than the valve-side contact portion 7a. It is provided in a sharp shape as shown in FIG. The knife edge shape is formed by pressurizing and plastically deforming simultaneously by press working when the disk valve 7 is press formed.
Thus, by providing the outer peripheral tip 7b of the disc valve 7 in the shape of a knife edge, it is possible to reduce the influence of the disc valve 7 from the flow of EGR gas when the valve is opened. Thereby, the electric actuator 10 can be reduced in size.

A second embodiment will be described with reference to FIGS. In the following embodiments, the same reference numerals as those in the first embodiment denote the same functional objects.
[Feature Technology 1 of Example 2]
The second embodiment is different from the first embodiment in the valve seat part 13.
As in the first embodiment, the valve seat part 13 of the second embodiment is in contact with the outer peripheral portion of the disc valve 7 when the valve is closed (when the valve body 3 closes the EGR flow path 1), and EGR gas leaks. A valve seat ring 12 is provided.
In the valve seat ring 12, the valve seat surface 12a with which the disc valve 7 abuts is linearly expanded toward the direction in which the disc valve 7 is disposed (downstream direction of the EGR gas flow), as in the first embodiment. Provided on the tapered surface. The valve seat surface 12a may be provided in the same spherical shape (curved surface) as the valve-side contact portion 7a (spherical shape) of the disc valve 7 to improve the sealing performance.

The valve seat part 13 of the second embodiment includes a radial bellows diaphragm 21 that functions as the flow direction displacement support means (bellows 14) and the radial direction displacement support means 15 (three thin-walled bulging portions 15a) in the first embodiment. I have.
The radial bellows diaphragm 21 is provided on the outer diameter side of the valve seat ring 12 to form a bellows portion that can be elastically deformed in the radial direction, and the valve seat ring 12 is connected to the EGR gas flow direction and the EGR flow path 1. It is supported so as to be displaceable in all radial directions. As shown in FIG. 7, a specific example of the radial bellows diaphragm 21 has a ring body made of an elastic member having a V-shaped cross section (made of resin in the second embodiment and made of metal in the third embodiment described later). A structure in which a plurality of continuous structures are formed from the side toward the outer diameter side is employed.

  Thereby, the valve seat ring 12 is supported by the radial bellows diaphragm 21 so as to be displaceable in all three-dimensional directions (all directions of the X-axis, Y-axis, and Z-axis indicating three dimensions). As a result, as in Example 1, the accuracy produced by providing the valve body 3 as a press-molded product by the centering action that occurs when the disc valve 7 is seated on the tapered surface of the valve seat surface 12a when the valve is closed. The decrease can be absorbed.

  The valve seat part 13 is provided with a fixing ring 22 on the outer diameter side of the radial bellows diaphragm 21. The fixing ring 22 is a fixing portion that is fixed to the inner wall of the EGR channel 1. For example, the valve seat part 13 is assembled to the housing 2 by being press-fitted into a predetermined assembly position on the inner wall of the EGR channel 1. It is what

As described above, the valve seat part 13 of the second embodiment includes the valve seat ring 12, the radial bellows diaphragm 21, and the fixing ring 22. The valve seat ring 12, the radial bellows diaphragm 21, and the fixing ring 22 include One member is provided.
Specifically, in the second embodiment, the valve seat ring 12, the radial bellows diaphragm 21, and the fixing ring 22 are integrally provided by a resin member (including rubber) that is elastically deformable and excellent in heat resistance and oil resistance. It is a thing.

[Feature Technique 2 of Example 2]
The valve seat part 13 of the second embodiment includes a flow direction thrust means 23 as means for bringing the valve seat ring 12 supported in the radial direction by the radial bellows diaphragm 21 against the disc valve 7.
The flow direction thrust means 23 is configured such that the downstream end of the EGR gas flow of the valve seat ring 12 is located downstream of the downstream end of the outermost diameter EGR gas of the radial bellows diaphragm 21. It is a means to dispose.

In the second embodiment, the flow direction thrust means 23 is provided in the radial bellows diaphragm 21. Specifically, the radial bellows diaphragm 21 of the second embodiment is shaped such that, in an unloaded state, the inner diameter side of the radial direction bellows diaphragm 21 is displaced to the downstream side of the EGR gas flow.
Thus, the valve seat surface 12a of the valve seat ring 12 is pressed against the disc valve 7 when the valve is closed, and the disc valve 7 is seated on the valve seat surface 12a when the valve is closed. Thus, the valve seat ring 12 can be aligned.

[Feature Technology 3 of Example 2]
In the valve seat part 13 of the second embodiment, the valve seat ring 12 and the radial bellows diaphragm 21 are affected by the EGR gas flow. Therefore, as shown in FIG. 8 (a), when the disc valve 7 is seated on the valve seat surface 12a when the valve is closed, the valve seat ring 12 and the radial bellows diaphragm 21 receive EGR gas pressure, The effect | action by which the seat ring 12 is pressed against the disc valve 7 arises, and the sealing performance of the disc valve 7 and the valve seat ring 12 can be improved.
As described above, since the self-sealing using the pressure of the EGR gas is employed, the problem that the EGR gas leaks in the EGR valve when the valve is closed can be eliminated, and the reliability can be improved.

[Feature Technique 4 of Example 2]
As shown in FIG. 8, the first and second shafts 5 and 6 in the second embodiment have a mechanism similar to that in the first embodiment, as shown in FIG. 8, when the disc valve 7 opens the EGR flow path 1. A shaft cam portion 16 is formed that contacts and moves the valve seat ring 12 by pushing it away from the disc valve 7.
The shaft cam portion 16 is provided on the first and second shafts 5 and 6 that are opposed to the valve seat ring 12. Specifically, the shaft cam portion 16 is for the shaft cam portion 16 to move the valve seat ring 12 to the upstream side in a range from the opening degree at which the valve body 3 opens the EGR flow path 1 to a predetermined opening degree. The relationship between the opening degree of the disc valve 7 and the distance traveled by the valve seat ring 12 being pushed upstream of the EGR gas is shown in FIGS. 9 (a) and 9 (b). It is determined by 16 shapes (cam profile).

As described above, when the first and second shafts 5 and 6 are provided with the shaft cam portions 16, the first and second shafts 5 and 6 rotate and the disc valve 7 opens the EGR flow path 1. In addition, the valve cam ring 16 moves to the side away from the disc valve 7 by the action of the shaft cam portion 16 accompanying the rotation of the first and second shafts 5 and 6 {the arrow F in FIG. 8 (b '). Reference}, a gap is formed between the valve seat ring 12 and the disc valve 7.
Thus, when the disc valve 7 opens the EGR flow path 1, a clearance is formed between the valve seat ring 12 and the disc valve 7, thereby causing contact wear between the disc valve 7 and the valve seat ring 12. In addition, the contact resistance between the disc valve 7 and the valve seat ring 12 can be suppressed, so that the torque required to rotate the first shaft 5 to drive the disc valve 7 can be reduced. The electric actuator 10 can be downsized.
Further, when the valve seat ring 12 and the disc valve 7 are forcibly separated when the valve is opened, it is possible to avoid a problem that the valve main body 3 is closed and to improve the reliability of the EGR valve. .

Embodiment 3 will be described with reference to FIG.
[Feature Technology 1 of Example 3]
In the second embodiment, as shown in FIG. 10A, an example in which the valve seat part 13 is provided with a resin is shown. That is, the example in which the valve seat ring 12, the radial bellows diaphragm 21, and the fixing ring 22 are integrally formed of resin is shown.
On the other hand, in the third embodiment, as shown in FIG. 10B, the valve seat part 13 is provided by a metal plate (metal spring) that can be elastically deformed. That is, the valve seat ring 12, the radial bellows diaphragm 21, and the fixing ring 22 are integrally provided by a metal spring. Thus, by providing the valve seat part 13 with a metal material, heat resistance and durability can be improved, and the reliability of the EGR valve can be improved.

[Feature Technology 2 of Example 3]
In the second embodiment, as shown in FIG. 10A, the flow direction thrust means 23 (means for bringing the valve seat ring 12 radially supported by the radial bellows diaphragm 21 into contact with the disc valve 7) is provided. The example provided in radial direction bellows diaphragm 21 was shown. Specifically, an example in which the inner diameter side of the radial bellows diaphragm 21 is formed to be shifted to the downstream side of the EGR gas flow is shown.
On the other hand, in the third embodiment, as shown in FIG. 10 (b), the downstream end of the EGR gas flow of the valve seat ring 12 is made to flow more than the innermost diameter of the radial bellows diaphragm 21. The flow direction thrust means 23 is provided by extending downstream. As a result, the valve seat surface 12a of the valve seat ring 12 is pressed against the disc valve 7 when the valve is closed, and the disc valve 7 is seated on the valve seat surface 12a when the valve is closed. On the other hand, the valve seat ring 12 can be aligned.

A fourth embodiment will be described with reference to FIG.
In the said Example 1, as shown to Fig.11 (a), the example which provides the valve seat component 13 with resin was shown. That is, the example in which the valve seat ring 12 and the bellows 14 including the annular engagement portion 14a are integrally formed with resin is shown.
On the other hand, in Example 4, as shown in FIG. 11B, the valve seat part 13 is provided by a metal plate (metal spring) that can be elastically deformed. That is, the valve seat ring 12 and the bellows 14 including the annular engagement portion 14a are integrally provided by a metal spring. Thus, by providing the valve seat part 13 with a metal material, heat resistance and durability can be improved, and the reliability of the EGR valve can be improved.

Embodiment 5 will be described with reference to FIGS.
[Feature Technique 1 of Example 5]
In the first embodiment, the procedure for assembling the EGR valve is as follows: (i) First, in the EGR flow path 1, the lower end of the first shaft 5 and the first valve support portion 8 are loosely fitted, and the second Loose fitting between the upper end of the shaft 6 and the second valve support portion 9 is performed. (Ii) Next, the loose fitting portion between the lower end of the first shaft 5 and the first valve support portion 8 and the second shaft 6. An example is shown in which the valve body 3 is welded and fixed to the first and second shafts 5 and 6 by welding the upper end of the valve and the loose fitting portion of the second valve support portion 9 respectively.

On the other hand, in the fifth embodiment, as shown in FIG. 12, the valve body 3 is fixed to the first shaft 5 and the second shaft 6 assembled to the electric actuator 10 in advance by welding or the like. Thereafter, as shown in FIG. 13 (a), the annular convex portion 10a of the electric actuator 10 to which the valve body 3 or the like is fixed is fitted into the assembly opening 2a of the housing 2 that forms the EGR flow path 1 inside. The electric actuator 10 is fastened to the housing 2 with screws or the like to complete the assembly. By providing in this way, the assembly | attachment property of an EGR valve can be improved.
The first shaft 5 is rotatably supported by a bearing assembled in the electric actuator 10.

[Feature Technique 2 of Example 5]
When the assembly method of the fifth embodiment shown above is employed, the periphery of the valve seat ring 12 is not supported by the inner wall surface of the EGR flow path 1 as shown in FIG. There is a possibility that the valve body 3 is displaced with respect to the disc valve 7.
Therefore, the valve seat part 13 of the fifth embodiment (specifically, the end face on the downstream side of the EGR gas flow in the valve seat ring 12) is provided with the first shaft 5 and the first shaft 5 as shown in FIG. The guide protrusions 24 sandwiching the two shafts 6 from both sides are integrally provided.

Then, the valve seat ring 12 is displaced with respect to the disc valve 7 of the valve body 3 by sandwiching each of the first shaft 5 and the second shaft 6 with the guide protrusion 24 provided on the valve seat part 13. The trouble can be avoided.
The distance between the guide protrusions 24 that sandwich the first and second shafts 5 and 6 (the distance at which the shaft is inserted) is set to be larger than the shaft diameters of the first and second shafts 5 and 6 at the portion to be sandwiched. The valve seat ring 12 is supported so as to be displaceable within a predetermined range with respect to the disc valve 7, and is provided so as to absorb the press molding error of the valve body 3.

  In the above embodiment, the example in which the present invention is applied to the EGR valve has been shown. However, the fluid is not limited to the exhaust gas, and other valves for opening and closing the gas fluid and the liquid fluid and adjusting the flow rate or pressure are used. The present invention may be applied to an apparatus.

1 EGR flow path (fluid path)
DESCRIPTION OF SYMBOLS 1a Level difference 2 Housing 3 Valve body 4 Shaft 5 1st shaft 6 2nd shaft 7 Disc valve 7a Valve side contact part 7b The outer periphery front-end | tip of a disc valve 8 1st valve support part 9 2nd valve support part 12 Valve seat ring 12a Valve seat surface 13 Valve seat part 14 Bellows (flow direction displacement support means)
14a Annular engagement part 15 Radial displacement support means 15a Thin bulging part 16 Shaft cam part 21 Radial bellows diaphragm 23 Flow direction thrust means

Claims (11)

A housing (2) forming a fluid passage (1) through which a fluid can pass, and opening and closing the fluid passage (1) by rotating in the fluid passage (1) or a passage area of the fluid passage (1) And a shaft (4) that is rotatably supported with respect to the housing (2) and rotationally drives the valve body (3).
In the valve device in which the center line of the shaft (4) is arranged perpendicular to the center line of the fluid passage (1),
The shaft (4) includes a first shaft (5) to which a driving force in a rotational direction is applied from the outside, and a second shaft (6) disposed on the central axis of the first shaft (5). The first shaft (5) and the second shaft (6) are arranged in a state of being separated inside the fluid passage (1),
The valve body (3)
A disc valve (7) having a disc shape and capable of closing the fluid passage (1);
A first valve support (8) provided on the outer peripheral side of the disc valve (7) and connecting the disc valve (7) and the first shaft (5);
A second valve provided on the outer peripheral side of the disc valve (7) on the side different from the first valve support portion (8) and connecting the disc valve (7) and the second shaft (6). A support portion (9), and 3 of the disc valve (7) and the first and second valve support portions (8, 9) when viewed from the direction along the plate surface of the disc valve (7). A valve device characterized by having a substantially U shape by a person. The valve device according to claim 1,
When the valve body (3) closes the fluid passage (1), the valve device abuts on the outer periphery of the disc valve (7), and the fluid passage (1) and the disc valve ( 7) comprising a valve seat part (13) having a valve seat ring (12) for closing the gap with
The three members of the disc valve (7) and the first and second valve support portions (8, 9) are press-formed products of metal plates,
In the valve seat ring (12), the valve seat surface (12a) with which the disc valve (7) abuts is a taper that expands in a curve or linearly toward the direction in which the disc valve (7) is arranged. Provided on the surface,
The valve seat component (13) includes a flow direction displacement support means (14) that supports the valve seat ring (12) so as to be displaceable in the flow direction of the fluid passage (1), and the valve seat ring (12). A valve device comprising a radial displacement support means (15) for supporting the fluid passage (1) so as to be displaceable in all radial directions. The valve device according to claim 2,
The first and second shafts (5, 6) are in contact with the valve seat ring (12) when the disc valve (7) opens the fluid passage (1). A valve device is characterized in that a shaft cam portion (16) is formed to press and move 12) away from the disc valve (7). The valve device according to claim 2 or 3,
The flow direction displacement support means (14) is a bellows arranged on the fluid upstream side of the disc valve (7),
The bellows (14) includes an annular engagement portion (14a) that engages with a step (1a) formed on the inner wall of the fluid passage (1) on the upstream side of the fluid. From the annular engagement portion (14a), A bellows part of the bellows (14) and the valve seat ring (12) are arranged on the fluid downstream side. In the valve apparatus in any one of Claims 2-4,
The radial displacement support means (15) is provided by three or more thin bulge portions (15a) provided on the outer peripheral side of the valve seat ring (12),
The valve device is characterized in that the valve seat ring (12) is supported so as to be displaceable in all radial directions of the fluid passage (1) by the spring action of the thin-walled bulging portion (15a). In the valve apparatus in any one of Claims 2-5,
The valve seat component (13) is provided as a single component with a resin material having a smooth surface. In the valve apparatus in any one of Claims 2-6,
In the disc valve (7), the valve side contact portion (7a) that contacts the valve seat ring (12) is provided in a spherical shape. The valve device according to claim 7,
In the disc valve (7), the outer peripheral tip (7b) provided on the outer periphery further than the valve-side contact portion (7a) is provided in a knife edge shape over the entire periphery. . The valve device according to claim 1,
When the valve body (3) closes the fluid passage (1), the valve device abuts on the outer periphery of the disc valve (7), and the fluid passage (1) and the disc valve ( 7) comprising a valve seat part (13) having a valve seat ring (12) for closing the gap with
The three members of the disc valve (7) and the first and second valve support portions (8, 9) are press-formed products of metal plates,
In the valve seat ring (12), the valve seat surface (12a) with which the disc valve (7) abuts is a taper that expands in a curve or linearly toward the direction in which the disc valve (7) is arranged. Provided on the surface,
The valve seat part (13) is:
A bellows portion is provided on the outer diameter side of the valve seat ring (12) and elastically deformable in the radial direction. The valve seat ring (12) is connected to the flow direction of the fluid passage (1) and the fluid passage. (1) a radial bellows diaphragm (21) which is supported so as to be displaceable in all radial directions;
A valve device comprising a fixing ring (22) provided on an outer diameter side of the radial bellows diaphragm (21) and fixed to an inner wall of the fluid passage (1). The valve device according to claim 9,
The valve seat part (13) has a downstream end of the valve seat ring (12) on the downstream side of the fluid downstream side of the outermost diameter fluid of the radial bellows diaphragm (21). Provided with a flow direction thrust means (23) arranged to be displaced,
This flow direction thrust means (23)
In a no-load state with respect to the radial bellows diaphragm (21), the radial bellows diaphragm (21) is formed such that the innermost diameter is displaced from the outermost diameter of the radial bellows diaphragm (21) to the fluid downstream side. Provided by
Alternatively, the valve device is provided by extending the fluid downstream end of the valve seat ring (12) to the fluid downstream side from the innermost diameter of the radial bellows diaphragm (21). The valve device according to claim 9 or 10,
The first and second shafts (5, 6) are in contact with the valve seat ring (12) when the disc valve (7) opens the fluid passage (1). A valve device is characterized in that a shaft cam portion (16) is formed to press and move 12) away from the disc valve (7).

Images