JP2011149465A - Rotary flow control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary flow control valve allowing the size of a valve element to be kept small while securing the large flow of a fluid, and achieving reliable controllability of a flow rate and a rotation angle of the valve element. <P>SOLUTION: The valve element 4 is notched in an axial direction. The valve element 4 is thereby miniaturized while securing the flow of the fluid to improve the rotation controllability of the valve element 4 due to a fall in moment of inertia, and the consequent flow controllability of the fluid. As a result, sufficient control responsiveness can be obtained even in a small actuator of small output or the like, and miniaturization and cost reduction of the rotary flow control valve itself can be achieved. Further, since the valve element 4 is rotated to allow notched planes 44, 45 to abut on a plane sidewall 21 of a valve chamber 2 to achieve mechanical detent, even when the actuator or the like misses the rotation angle of the valve element 4, an appropriate reference rotation angle can be detected on the basis of a mechanical detent position. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a fluid flow control valve, and more particularly to a rotary flow control valve in which the size of a cylindrical rotary valve body and a housing is reduced.

  A flow control valve that rotates a cylindrical rotary valve body has a cylindrical valve body that is rotated (spinned) by an actuator or the like, and a flow path is formed inside or on the surface of the valve body. The position of the valve body is displaced relative to the housing as the valve body rotates, and fluid flows when the flow path communicates with a port provided in the housing. The flow rate of the fluid is controlled by changing the communication cross-sectional area according to the rotation angle of the valve body.

  However, in this configuration, in order to increase the cross-sectional area of the flow path in order to ensure the flow rate, the size of the valve body must be increased. Increasing the size of the valve body causes an increase in the moment of inertia around the rotation axis, leading to a deterioration in control responsiveness with an actuator or the like. For this reason, it is necessary to increase the size of the actuator and the like, and there is a problem that the flow control valve unit itself is increased in size and cost.

  In order to solve this problem, Patent Document 1 proposes a flow control valve that eliminates unnecessary portions of the valve body to reduce the moment of inertia, and can perform a reciprocating rotary motion with good response even with a small and small output actuator or the like. ing. However, when the valve body is controlled at a high speed, the load on the actuator or the like is large and an abnormality is likely to occur. Also, if the rotation angle of the valve element is lost due to an abnormality in the actuator or the like, it takes time to recover.

JP 2005-344803 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary flow control valve capable of maintaining a large fluid flow rate while keeping the size of the valve body small and realizing reliable controllability of the flow rate and the rotation angle of the valve body.

  The present invention includes a cylindrical housing having a valve chamber having a first port on a bottom wall and a second port on a cylindrical wall, and is coaxially accommodated in the valve chamber, and is disposed at the axial center portion of one end surface. It has a first opening that is always connected to the first port provided, and a second opening provided in the cylindrical surface, and the fluid flows by connecting the first opening and the second opening inside. Rotation for controlling the flow rate of fluid by adjusting the degree of communication between the second opening and the second port provided in the housing by rotation of the valve body. In the flow rate control valve, the valve body has a notch surface that is missing in the axial direction, leaving the axial center portion including the first opening portion and the cylindrical surface portion including the second opening portion. It has a cylindrical wall on which the cylindrical surface portion slides, and a rotation stop wall on which the notched surface abuts.

  In the present invention, the valve body is notched in the axial direction, so that the valve body is reduced in size while ensuring a flow rate, and the rotation controllability of the valve body due to a decrease in the moment of inertia and the accompanying fluid flow rate controllability are improved. As a result, even a small and small output actuator or the like can achieve sufficient control responsiveness, and the flow control valve unit itself can be reduced in size and cost. In addition, since the valve body rotates and the notched surface hits the rotation stop wall of the valve chamber, the rotation of the valve body is mechanically stopped. As a reference, an appropriate reference rotation angle can be found.

It is front sectional drawing of the rotary flow control valve concerning Example 1 of this invention. It is a perspective view of the valve body concerning Example 1. FIG. It is the front view (a) of the valve body concerning Example 1, and a top view (b). 1 is a cross-sectional plan view of a rotary flow control valve according to Embodiment 1. FIG. It is front sectional drawing of the rotary flow control valve concerning Example 2 of this invention.

  A mode for carrying out the invention will be described together with embodiments shown in the drawings.

  FIG. 1 is an outline of an exhaust gas recirculation system for an automobile engine using a rotary flow control valve 1 according to Embodiment 1 of the present invention. The rotary flow control valve 1 includes a housing 3 having a cylindrical valve chamber 2 and a columnar valve body 4 accommodated coaxially in the valve chamber 2. An actuator 5 that rotates the valve body 4 is installed above the housing 3 in the figure. In this embodiment, as shown in FIG. 4, the valve chamber 2 has a cross-sectional shape in which a part of a cylinder is cut out by a flat side wall 21.

  As shown in FIG. 4, the housing 3 has an external shape similar to that of the valve chamber 2, and includes a cylindrical side wall 31, a bottom wall 32, and a top wall 33 as shown in FIG. 1. The side wall 31 includes a cylindrical wall 37 and a flat wall 38 that forms the flat side wall 21, and a circular cylindrical outport 34 projects from the cylindrical wall 37 so as to be orthogonal to the cylindrical wall 37. A circular cylindrical import 35 projects from the axial center of the bottom wall 32, and a shaft hole 36 is provided in the top wall 33. The import 35 is connected to the exhaust path 11 of the engine, and the outport 34 is connected to the intake path 12 of the engine.

  As shown in FIGS. 2 and 3, the outer shape of the valve body 4 is formed by cutting a cylinder by two notch planes 44 and 45 that are parallel to the axis and orthogonal to each other, leaving the axial center portion 42 and the cylindrical surface portion 43. Further, the crossing portion of the notch planes 44 and 45 is notched, and a small cylindrical surface 46 coaxial with the axial center portion 42 is formed. A shaft portion 48 that is coaxial with the cylindrical surface portion 43 protrudes from or is connected to the upper end surface 47 (upper side in the drawing) of the valve body 4. The shaft portion 48 is inserted through the shaft hole 36 and is connected to the actuator 5 via a ball bearing 52. A seal member 51 is interposed in the gap between the shaft portion 48 and the shaft hole 36. The seal member 51 is, for example, an elastic ring, and any material can be used as long as a desired seal performance can be realized.

  As shown in FIGS. 2 and 3, a curved flow path 6 is provided inside the valve body 4. In the flow path 6, an inlet 61 through which exhaust gas flows into an axial center portion 42 of a lower end surface 41 (downward in the drawing) of the valve body 4 is opened, and an outlet 62 through which exhaust gas flows out opens into the cylindrical surface portion 43. The inlet 61 is provided in a cylindrical projecting portion 63 formed in the valve body 4, and this cylindrical projecting portion 63 is inserted into the import 35 and serves as a rotating support shaft on the lower side of the valve body 4 in the figure. ing. A seal member 64 is interposed on the rotating surfaces of the import 35 and the cylindrical protrusion 63. The seal member 64 is, for example, an elastic ring, and any material can be used as long as a desired seal performance can be realized. In this embodiment, the inlet 61 is circular with the axis of the valve body 4 as the center, and the outlet 62 is circular with an opening in a direction perpendicular to the axis of the valve body 4. The flow path 6 is curved inside the valve body 4 and is deflected by 90 degrees. A sealing means 65 is provided between the cylindrical surface 43 of the valve body 4 and the sliding surface of the valve chamber 2. The sealing means 65 is provided outside the outlet 62 of the cylindrical surface 43, and includes a groove 68 concentric with the outlet 62 and a sealing member 69. The seal member 69 is, for example, an elastic ring, and any material can be used as long as a desired seal performance can be realized.

  The valve body 4 is rotatably supported around the rotation axis L1, and the actuator 5 reciprocates the valve body 4 within an angle range of 90 degrees. The inlet 61 is always connected to the import 35, and the flow rate of the recirculated exhaust gas supplied to the intake passage 12 is changed by changing the communication cross-sectional area between the outport 34 and the outlet 62 according to the rotation angle of the valve body 4. To control. FIG. 1 shows a fully opened state.

Next, confirmation of the reference rotation angle will be described with reference to FIG.
FIG. 4 is a plan sectional view of the rotary flow control valve 1 according to the first embodiment, showing a fully closed state (a) and a fully open state (b). The valve chamber 2 has a cross-sectional shape in which a part of a cylinder is cut out by a flat side wall 21. The planar side wall 21 functions as a mechanical rotation stop wall of the valve body 4.

  Even if the rotation angle of the valve body 4 is lost during the rotation operation due to an abnormality of the actuator 5 or the like during the rotation control of the valve body 4, the two notch planes 44 and 45 that are parallel to the axis and orthogonal to each other and the cylinder The rotation stop portions 66 and 67 that are the intersections with the surface portion 43 come into contact with the planar side wall 21 that is a mechanical rotation stop wall. Since it can be determined from the rotation direction of the valve body 4 which one of the rotation stop portions 66 and 67 is in contact, the rotation angle can be reset. For example, the reference rotation angle can be set to 0 degrees when the rotation stopper 66 contacts the planar side wall 21 and 90 degrees when the rotation stopper 67 contacts the plane sidewall 21.

FIG. 5 shows a front sectional view in the case where the cylindrical valve body is a truncated cone. The same reference numerals as those in the first embodiment denote the same or the same functions.
In the case of such a valve body shape, an urging member 71 is provided between the valve body 7 and the valve chamber 8, and the valve body 7 is urged by the urging member 71 in the direction of a small diameter of the truncated cone. The clearance between the valve chamber 8 and the valve chamber 8 is reduced, and the sealing performance can be further enhanced. The urging member 71 is, for example, a leaf spring, and any material can be used as long as a desired urging performance can be realized.

  Although the embodiments of the present invention have been described above, various design changes can be made without departing from the scope of the present invention. For example, in the embodiment, the rotation angle range of the valve body 4 is 90 degrees, but it may be a minimum rotation angle range smaller than 90 degrees that can be fully opened and fully closed. Further, in the embodiment, the shapes of the outlet 62 of the valve body 4 and the outport 34 of the housing 3 are provided in a circular shape, but the shapes of the outlet 62 of the valve body 4 and the outport 34 of the housing 3 are defined as the rotation angle of the valve body 4. It is also possible to use a square type in which the relationship of the communication cross-sectional area changes linearly. In the embodiment, the flow path 6 is curved inside the valve body 4 and is deflected by 90 degrees. However, the deflection angle is not limited to 90 degrees. In the embodiment, the valve body inlet and the valve body outlet are uniquely set, but the valve body inlet can be set as the valve body outlet and the valve body outlet can be set as the valve body inlet. It is. Further, the valve body shape and the like of the present invention may be realized by cutting or by casting.

  Further, the rotary flow control valve 1 of the present invention can be applied to any use other than the recirculation exhaust gas flow control valve of the exhaust gas recirculation system.

  The rotary flow control valve with a small valve body size and a mechanical anti-rotation mechanism in the present invention realizes downsizing of the flow control valve itself and reliable control of the fluid flow rate and the valve body rotation angle. it can. For this reason, it is possible to realize confirmation of an appropriate reference rotation angle when the responsiveness of high-speed flow rate control and the rotation angle of the valve body are lost.

DESCRIPTION OF SYMBOLS 1 Rotary flow control valve 2 Valve chamber 21 Planar side wall (rotation stop wall) of valve chamber
3 Housing 31 Housing side wall (cylindrical wall)
32 Housing bottom wall 34 Out port (second port)
35 Import (1st port)
37 cylindrical wall of housing 38 flat wall of housing 4 valve body 42 axial center part of valve body 43 cylindrical surface part of valve body 44 notch plane 45 notch plane 46 small cylindrical surface 52 ball bearing 6 flow path 61 inlet (first opening) Part)
62 Exit (second opening)
66 Anti-rotation part 67 Anti-rotation part 7 Valve body of truncated cone 71 Energizing member 8 Valve chamber of truncated cone

Claims (4)

A cylindrical housing having a valve chamber with a first port on the bottom wall and a second port on the cylindrical wall;
A first opening that is coaxially housed in the valve chamber and is always connected to the first port provided in the axial center of one end face, and a second opening provided in the cylindrical face. A cylindrical valve body provided with a flow path through which fluid flows by connecting the first opening and the second opening,
In the rotary flow control valve that controls the flow rate of the fluid by adjusting the degree of communication between the second opening and the second port provided in the housing by the rotation of the valve body,
The valve body has a notch surface that is missing in the axial direction, leaving the cylindrical surface portion including the axial center portion including the first opening portion and the second opening portion,
The rotary flow control valve according to claim 1, wherein the valve chamber has a cylindrical wall on which the cylindrical surface portion of the valve body slides and a rotation stop wall on which the notch surface abuts. The rotary flow control valve according to claim 1,
The valve body is a cylinder,
The cut-out surface of the valve body has a first plane provided by cutting a cylinder in the axial direction and a second plane provided by cutting in the axial direction so as to be substantially orthogonal to the first plane. The rotary flow control valve is characterized in that the valve chamber has a planar side wall that abuts on either the first plane or the second plane. The rotary flow control valve according to claim 1,
The valve body is a truncated cone;
The cut-out surface of the valve body has a first plane provided by cutting the truncated cone in the axial direction and a second plane provided by cutting in the axial direction so as to be substantially orthogonal to the first plane. And the said valve chamber has a plane side wall which contact | abuts either one of the said 1st plane or the said 2nd plane, The rotary flow control valve characterized by the above-mentioned. The rotary flow control valve according to claim 3,
A rotary flow rate control valve characterized in that an urging means for urging the valve body in a small diameter direction of the truncated cone is provided.

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