JP4879662B2 - Reed valve - Google Patents

Description

  The present invention relates to a reed valve that controls the inflow of air using a reed-shaped valve body.

The reed valve is provided with a reed valve stopper that regulates the warping of the valve body in order to prevent the reed valve body from overshooting during intake or exhaust, resulting in over-stress and not returning to the original shape. (Patent Document 1).
JP 2004-232712 A

  However, since the conventional reed valve stopper is configured to screw the metal plate to the valve body, there is a problem that the number of parts increases and the assembly process increases. Further, in the conventional form, there is a problem that the movement of the reed valve is restricted by fluid resistance such as air sandwiched between the reed valve and the stopper.

  The object of the present invention is to provide a low-cost reed valve that is lightweight while ensuring high air permeability by eliminating a separate reed valve stopper.

The reed valve of the present invention includes a main body provided with a valve hole, and a lead-shaped valve body that opens and closes the valve hole and has a fixed end fixed to the main body, and is the other end of the valve body. The free end includes a locking portion that is engaged with a locking hole provided in the main body and restricts the warping of the valve body to a predetermined range.

  The locking portion is a free end tip that is bent toward the main body side from the flat portion of the valve body that closes the valve hole, and the leading end is engaged with the locking hole so that the valve body is within a predetermined range. When the valve is opened, the tip is locked in the locking hole. In the main body, the opening of the locking hole formed on the first surface on which the valve body is placed is the opening of the locking hole formed on the second surface opposite to the first surface. The tip portion bent toward the main body side is further bent so as to be parallel to the flat portion.

  The locking hole is, for example, a hole that communicates the first surface of the main body on which the valve body is placed and the side surface of the main body.

  As described above, according to the present invention, it is possible to provide a low-priced low-cost reed valve while ensuring high air permeability by eliminating a separate reed valve stopper.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing an outline of a secondary air system in which a reed valve according to an embodiment of the present invention is used. In the present embodiment, the secondary air system will be described as an example, but the system in which the reed valve is used is not limited to the secondary air system, and may be an intake system, for example.

  An intake pipe 12 is attached to an intake port 11 of the cylinder head 10 of the engine, and outside air is guided into the cylinder through an air cleaner 13. An exhaust pipe 15 is attached to the exhaust port 14, and the exhaust pipe 15 is connected to an exhaust muffler (not shown).

  The exhaust port 14 is provided with a secondary air supply path 16 for supplying secondary air to the exhaust system. Secondary air is supplied to the secondary air supply path 16 via an air cleaner 17, an air cut valve 18, and a reed valve 19. The air cut valve 18 includes a diaphragm chamber that communicates with the intake pipe 12 via a vacuum pipe 20. When negative pressure is generated in the exhaust port 14, the diaphragm 21 is activated and the control valve 22 of the air cut valve 18 opens. Is done.

  A reed valve 19 provided between the air cut valve 18 and the secondary air supply path 16 is a check valve that allows air to flow from the air cut valve 18 toward the secondary air supply path 16. The valve is opened only when the negative pressure is generated, the negative pressure is introduced to the air cut valve 18, the control valve 22 is opened, and the secondary air is supplied to the exhaust port 14.

  Next, the structure of the reed valve 19 according to the first embodiment will be described in more detail with reference to FIGS. 2 and 3 are side cross-sectional views of the reed valve 19 of the first embodiment excluding the housing portion. FIG. 2 shows the valve body in a closed state, and FIG. 3 shows the valve body in an open state. Indicated. FIG. 4 is a perspective view of the reed valve of FIG. 3 as viewed obliquely from above.

  In FIG. 1, since the air cut valve 18 is drawn on the upper side and the secondary air supply path 16 is drawn on the lower side, the reed valve 19 is also arranged to supply the secondary air from the upper side to the lower side. However, the reed valve 19 in FIGS. 2 to 4 is depicted in such an arrangement that air flows from the lower side to the upper side.

  The reed valve 19 mainly includes a lead-shaped valve body 23 and a valve body 24 to which the valve body 23 is attached. The valve body 23 is made of a flexible thin plate member (for example, a thin flat stainless steel plate), and the valve main body 24 is a thick plate-like member made of a rigid body such as aluminum, aluminum alloy, or other metal, For example, it is formed by die casting.

  A valve hole 25 is formed substantially at the center of the valve body 24. The valve body 23 is a thin plate large enough to cover the valve hole 25, and is placed so as to cover and close the valve hole 25 on one surface (valve mounting surface) 24 </ b> S of the valve body 24. One end (fixed end) 23A is fixed to the valve body 24 by a fixing means. In this embodiment, the bolt 26 is used as a fixing means, and a screw hole 24H that is screwed with the bolt 26 is formed in the valve mounting surface 24S of the valve body 24. A heat resistant resin layer is formed on one surface of the valve mounting surface 24S of the valve body 24. For example, a fluororesin coating is applied to form a fluororesin layer.

  The valve body 24 is formed with a locking hole 27 adjacent to the valve hole 25. The locking hole 27 is a hole into which the free end 23B, which is the end opposite to the fixed end 23A of the valve body 23, is engaged, and is opposite to the side on which the fixed end 23A is attached across the valve hole 25. Formed.

  The valve body 23 is mainly composed of a flat region (flat portion) that closes the valve hole 25, but the free end 23B is bent from the flat portion toward the valve body 24 (first bent portion 231). Further, the tip is bent in the direction parallel to the flat portion toward the opposite side to the fixed end 23A (second bent portion 232). In the present embodiment, the locking hole 27 is similar to the valve hole 25, the valve mounting surface (downstream surface) 24S of the valve body 24 on which the valve body 23 is placed to the surface opposite to the valve mounting surface 24S (upstream). This is a hole communicating with the side surface.

  The opening on the valve mounting surface 24S side of the locking hole 27 is slightly longer than the lateral width of the valve body 23 along the width direction (the direction perpendicular to the direction connecting the fixed end 23A and the free end 23B of the valve body 23). Presents a slit-like shape. Further, the opening formed on the upstream surface of the locking hole 27 has, for example, a width wider than the slit width in the opening on the valve mounting surface 24S side and reaches the vicinity of the valve mounting surface 24S. That is, a step portion 27A is formed at the boundary between the opening on the valve mounting surface 24S side and the opening formed from the upstream surface. In the present embodiment, the stepped portion 27 </ b> A is disposed on the side opposite to the valve hole 25.

  That is, the first bent portion 231 passes through the slit-shaped opening of the valve mounting surface 24S and extends into the opening formed from the upstream surface to the vicinity of the valve mounting surface 24S. As shown in FIG. 2, when the valve body 23 is closed, the second bent portion 232 is positioned in the vicinity of the upstream surface in the locking hole 27. When the pressure on the upstream side with respect to the valve body 23 becomes higher than the pressure on the downstream side, as shown in FIG. 3, the valve body 23 is warped upward (downstream) due to the pressure difference around the fixed end 23A and opened. . At this time, the free end 23B is lifted upward until the second bent portion 232 engages with the stepped portion 27A.

  That is, by locking the second bent portion 232 to the stepped portion 27A, the valve body 23 can be prevented from further warping than the position of FIG. 3, and the valve body 23 warps beyond the elastic limit, It is possible to prevent the hole 25 from being returned to the position where it is closed. That is, by adjusting the shape of the free end 23B, the range in which the valve body 23 can be opened can be restricted to a predetermined range.

  FIG. 5 shows a schematic cross-sectional view of the configuration when the valve body 24 of the first embodiment is housed in the housing 30 of the reed valve 19. In FIG. 5, the valve body 23 is omitted. As shown in FIG. 5, the locking hole 27 is a hole that communicates from the upstream side to the downstream side of the valve body 24, and therefore needs to be hermetically isolated from the flow path 40 of the reed valve 19.

  Therefore, as shown in FIG. 5, the housing 30 is provided with a pedestal 31 of the partition wall 24 </ b> A of the valve body 24 that separates the valve hole 25 and the locking hole 27. It is isolated from the passage 40 and the air in the passage 40 is prevented from flowing downstream through the locking hole 27. A seal member 32 is inserted between the housing and the valve main body 24.

  As described above, according to the present embodiment, there is no need for a separate reed valve stopper as in the prior art, and the number of parts can be reduced with a simple configuration and the assembly cost can be reduced.

  FIG. 6 shows a modification of the first embodiment. In the first embodiment, the second bent portion 232 is bent toward the side opposite to the fixed portion 23A of the valve body 23, but the second bent portion 233 of the modification is directed toward the fixed portion 23A. It is bent. That is, the distal end portion of the valve body 23 has a U-shape or a U-shape, and the step portion 27B provided in the locking hole 27 is formed on the valve hole 25 side. Other points are the same as in the first embodiment.

  The engagement method between the free end of the valve body and the locking hole is not limited to the present embodiment. For example, only a part of the free end is bent and engaged with the locking hole. You may make it comprise a stop part. In the present embodiment, the second bent portion is used for locking, but the second bent portion is not provided, and one bent portion may be engaged with the side wall or the step portion of the locking hole. It is also possible to provide a locking portion in the lateral direction. Further, the shape and number of the locking holes are not limited to the present embodiment.

  Next, a reed valve according to a second embodiment of the present invention will be described with reference to FIGS. Many parts of the configuration of the reed valve according to the second embodiment are the same as the configuration of the reed valve according to the first embodiment.

  FIG. 7 is a perspective view of the valve body 50 of the second embodiment, and FIG. 8 is a side sectional view of the valve body 50 of FIG. Since the locking hole 27 of the first embodiment communicates from the upstream surface of the valve body 24 to the valve mounting surface (downstream surface), when the valve body 24 is attached to the housing 30, It was necessary to provide the housing 30 with a pedestal 31 for isolating the stop hole 27 from the flow path 40.

  In the valve body 50 of the second embodiment, the locking hole 51 communicates from the valve mounting surface 50A to the side surface 50B of the valve body 50. Since the four side surfaces of the valve body 50 are conventionally configured to come into airtight contact with the inner wall of the housing by a sealing member when the valve body 50 is assembled to the housing, one opening of the locking hole 51 is provided. Is provided on the side surface of the valve body 50, the locking hole 51 can be hermetically isolated from the flow path without changing the configuration of the housing as in the first embodiment.

  As described above, according to the second embodiment, the same effects as those of the first embodiment can be obtained without changing the configuration of the housing.

It is a schematic diagram which shows the outline | summary of the secondary air system in which the reed valve which is one Embodiment of this invention is used. It is a sectional side view at the time of valve closing of the valve body of a 1st embodiment except a case part. It is a sectional side view at the time of valve opening of the valve main body of 1st Embodiment except a housing | casing part. FIG. 4 is a perspective view of the valve body of FIG. 3. It is a typical sectional side view when the valve body of a 1st embodiment is attached to a case. It is a sectional side view of the modification of the reed valve of 1st Embodiment. It is a perspective view of the valve body in a 2nd embodiment. It is a sectional side view of the valve body in a 2nd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cylinder head 11 Intake port 12 Intake pipe 13 Air cleaner 14 Exhaust port 15 Exhaust pipe 16 Secondary air supply path 17 Air cleaner 18 Air cut valve 19 Reed valve 23 Valve body 23B Free end 24 Valve body 25 Valve hole 27 Locking hole 27A stage Part 231 first bent part 232 second bent part

Claims (3)

A main body provided with a valve hole, and a fixed end that is one end of the valve hole that opens and closes the valve hole, and a free end that is the other end of the valve body. A locking portion that is engaged in a locking hole provided in the main body and restricts the warping of the valve body to a predetermined range;
The locking portion is a distal end portion of the free end that is bent toward the main body side from a flat portion of a valve body that closes the valve hole, and the distal end portion is engaged with the locking hole, The reed valve , wherein when the valve body is opened to a predetermined range, the tip end portion is locked in the locking hole . In the main body, an opening of the locking hole formed in the first surface on which the valve body is placed is formed in a second surface that is a surface opposite to the first surface. 2. The reed valve according to claim 1 , wherein the leading end portion which is smaller than the opening of the locking hole and is bent toward the main body side is further bent so as to be parallel to the flat portion.   The reed valve according to claim 1, wherein the locking hole is a hole that communicates a first surface of the main body on which the valve body is placed and a side surface of the main body.

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