EXHAUST VALVE DEVICE
An exhaust valve device includes a valve body, a valve seat, a support shaft, a coil spring, and a cushion member. The valve body is placed in an exhaust passage in a silencer, and configured to open and close the exhaust passage. The valve body abuts against the valve seat when the valve body is closed. The support shaft is fixed to the valve seat, and supports the valve body to be able to swing freely. The support shaft is inserted in the coil spring. The coil spring biases the valve body. The cushion member is interposed between the coil spring and the support shaft. The cushion member is rotatable relative to the support shaft.
This is a U.S. national phase application of PCT/JP2018/027128, filed on Jul. 19, 2018, which claims priority to Japanese Patent Application No. 2017-140506, filed on Jul. 20, 2017, and Japanese Patent Application No. 2017-174582, filed on Sep. 12, 2017. The entire disclosures of Japanese Patent Application Nos. 2017-140506 and 2017-174582, are hereby incorporated herein by reference.
TECHNICAL FIELDThe present invention relates to an exhaust valve device (exhaust control valve) that opens and closes an exhaust passage in a silencer according to the exhaust pressure of exhaust gas from an engine.
BACKGROUND ARTFor example, for an intake control valve for which swirl is generated within a fuel chamber to improve the combustion state of a mixed gas in a multi-cylinder engine for an automobile, a rattle prevention device of a rotating shaft disclosed in Japanese Patent No. 4180760 is adopted. The rattle prevention device of a rotating shaft for an intake control valve disclosed in this reference comprises: a cushion member that can be expanded by a kerf provided in the center axis line direction and that is fitted to be rotatable on a small diameter part of the rotating shaft; and a spring member that pressure welds on the outer circumference surface of this cushion member, and presses the rotating shaft in the direction perpendicular to the center axis line. Also, with this rattle prevention device of a rotating shaft for an intake control valve a protrusion that extends in the center axis line direction is provided projecting outward on the cushion member, and the kerf is formed on the protrusion.
Also, when the spring member is set by pressure welding on the cushion member and the spring member contacts the protrusion, the cushion member rotates with a slight imbalance of the spring load that acts on the protrusion, and the kerf moves to a position that does not contact the spring member. Also, when the cushion member rotates according to the rotation of the rotating shaft, the protrusion contacts the spring member, inhibiting further rotation, and preventing contact of the kerf and the spring member. As a result of these, the cushion member is expanded by the spring member, and wear due to direct contact of the rotating shaft and the spring member is prevented.
SUMMARYHowever, with the conventional control valve, since the cushion member is fitted to be rotatable on the small diameter part of the rotating shaft, with the cushion member, relative movement occurs with respect to the spring member, and friction occurs with the spring member, so it was difficult to sufficiently suppress wear of the spring member.
In light of that, the purpose of the present invention is to address the problems noted above.
An exhaust valve device of one mode of the present invention comprises: a valve body that is placed in an exhaust passage in a silencer, and that opens and closes the exhaust passage; a valve seat that the valve body abuts when the valve body is closed; a support shaft that is fixed to the valve seat, and that supports the valve body to be able to swing freely; a coil spring in which the support shaft is inserted, that biases the valve body; and a cushion member that is interposed between the coil spring and the support shaft. The cushion member is rotatable relative to the support shaft.
With the exhaust valve device of one mode of the invention of the present application, it is possible to more reliably suppress wear of the coil spring.
Following, embodiments of the present invention are explained based on the drawings.
Here, for convenience of explanation, the direction of the flow of exhaust gas from upstream to downstream (direction shown by arrow R2 in
As shown in
As shown in
As shown in
As shown in
On the bottom end edge of the flat plate part 12 of the valve seat 11, a stopper receiving part 15 that regulates swinging of the valve body 20 is formed bent integrally to the rear. On this stopper receiving part 15, a notch part 15a is formed near one side end part 14b. Also, on the bottom side of both side end parts 14b, 14b of the valve seat 11, a pair of flanges 16, 16 having a shaft through hole 16a at the center is integrally formed. A support shaft 17 penetrates each shaft through hole 16a of this pair of flanges 16, 16. The support shaft 17 that penetrates each shaft through hole 16a of this pair of flanges 16, 16 has both end sides fixed by welding, etc., to the pair of flanges 16, 16.
As shown in
At the bottom end edge of the flat plate part 21 of the valve body 20, an inclined piece 24 is formed bent inclined to the rear. At the center of this inclined piece 24, a stopper 25 that abuts the stopper receiving part 15 of the valve seat 11 is formed integrally projecting. The stopper 25 of this valve body 20 abuts the stopper receiving part 15 of the valve seat 11, and the angle up to the angle at which the valve body 20 swings is regulated is the prescribed opening degree of the valve body 20.
Also, close to one side part 23 of the inclined piece 24, a notch part 24a is formed. Furthermore, at the bottom side of both side parts 23, 23 of the valve body 20, a pair of flanges 26, 26 having a shaft through hole 26a at the center is integrally formed. The support shaft 17 supporting the valve body 20 to swing freely on the valve seat 11 is penetrated inside each shaft through hole 26a of this pair of flanges 26, 26.
Furthermore, at the center of the flat plate part 21 of the valve body 20, a circular convex part 21a is formed integrally projecting at the front surface side, and around this circular convex part 21a of the front surface of the flat plate part 21, a heat resistant, annular plate shaped cushioning mat 27 is fixed by spot welding, etc. When the valve body 20 is closed, the flat plate part 21 of the valve body 20 is made to abut the flat plate part 12 of the valve seat 11 without gaps with the cushioning mat 27 interposed. Also, annular bushes 28 are made to be penetrated by the support shaft 17 between each of the pair of flanges 16, 16 of the valve seat 11 and the pair of flanges 26, 26 of the valve body 20. The valve body 20 is axially supported to swing freely on the support shaft 17 with this pair of bushes 28, 28 interposed.
Also, as shown in
As shown in
As shown in
When the valve body 20 is a prescribed opening degree, the upper wall 41 of the outer cylinder 40 and each arc shaped center part 42a of both side wall parts 42, 42 are made to respectively cover the top part 22 and both side parts 23, 23 of the valve body 20 open in resistance to the biasing force of the torsion coil spring 30. The prescribed opening degree of the valve body 20 is the angle at which the valve body 20 swings when the exhaust pressure of the exhaust gas G is at maximum, and for example, is set to maximum 45°. By doing this, when the valve body 20 is opened, the periphery of the valve body 20 is covered by the outer cylinder 40, so the opening degree of the valve body 20 increases, and it is made possible to obtain a low back pressure effect.
With the exhaust valve device 10 of the first embodiment, when at low engine speed, the exhaust pressure of the exhaust gas G that flows inside the silencer 1 is low, so the valve body 20 of the exhaust valve device 10 is closed. When this valve body 20 is closed, the exhaust gas G flows as shown by the arrow R1 in
Also, in a medium to high rotation speed when the rotation speed of the engine exceeds a prescribed low speed rotation range, and the exhaust pressure of the exhaust gas G exceeds the biasing force by the elasticity of the torsion coil spring 30, the valve body 20 of the exhaust valve device 10 opens in resistance to the elastic biasing force of the torsion coil spring 30. In this case, with the intermediate route of the inner pipe 7 from the end part 5a of the inlet pipe 5, the flow of the exhaust gas G becomes two flows: the flow shown by arrow R1 in
The support shaft 17 that penetrates between the pair of flanges 16, 16 of the valve seat 11 supports the pair of flanges 26, 26 of the valve body 20 to swing freely with the bushes 28 interposed. Furthermore, the torsion coil spring 30 that biases the valve body 20 in the closing direction is externally mounted on this support shaft 17. For this reason, the exhaust valve device 10 can reduce the number of components by that amount, and it is possible to simplify the overall structure.
Also, as shown in
Furthermore, by providing on the valve seat 11 the stopper receiving part 15 that regulates swinging of the valve body 20, it is possible to make the opening degree (swing angle) regulated by the stopper 25 of the valve body 20 contacting the stopper receiving part 15 of the valve seat 11 be the maximum angle.
Second EmbodimentAs shown in
With the exhaust valve device 110 of the second embodiment, as shown in
As shown in
With the exhaust valve device 210 of the third embodiment, as shown in
As shown in
With the exhaust valve device 310 of the fourth embodiment, as shown in
As shown in
With the conventional control valve, the cushion member was fitted to be rotatable on the small diameter part of the rotating shaft, so relative movement of the cushion member with respect to the spring member was generated, and friction was generated between the cushion member and the spring member. For this reason, it was difficult to reliably suppress wear of the spring member. Also, since it was necessary to form the small diameter part for fitting the cushion member on the rotating shaft, the cost was higher by that amount.
In contrast to this, with the exhaust valve device 310 of the fourth embodiment, as shown in
As shown in
With the exhaust valve device 410 of the fifth embodiment, the cylindrical collar members 429D, 429E divided in two for the support shaft 17 between the pair of flanges 26, 26 of the valve body 20 are respectively inserted. By doing this, during opening and closing of the valve body 20, of the two cylindrical collar members 429D, 429E, the collar member 429D rotates together according to rotation of the one end 31 of the torsion coil spring 30. For this reason, it is possible to easily, reliably, and at low cost, prevent wear of the one end 31 side of the torsion coil spring 30.
With a structure of insertion with only one collar member with the support shaft, this one collar member does not rotate together with the torsion coil spring according to rotation of one end side of the torsion coil spring. In contrast to this, with each embodiment of the fourth embodiment and the fifth embodiment, there is insertion for each of the three-division cylindrical collar members 329A, 329B, 329C, or the two-division cylindrical collar members 429D, 429E with the support shaft 17, and by having the collar member 329A or the collar member 429D positioned at the one end 31 side of the torsion coil spring 30 rotate together according to the rotation of the one end 31 side of the torsion coil spring 30, wear of the torsion coil spring 30 is prevented.
In other words, by forming the cushion members placed between the support shaft and the coil spring to be cylindrical, and having insertion of a plurality with the support shaft, by having at least one of the plurality of cushion members move together with the coil spring, wear of the coil spring is prevented.
According to each embodiment, the exhaust valve device was attached to the through hole formed in the baffle plate (partition plate) that partitions the interior of the silencer, but it is also possible to attach the exhaust valve device to the end part of the inlet pipe (exhaust pipe) in the silencer.
Above, embodiments of the present invention were explained, but these embodiments are merely examples noted to make the present invention easier to understand, the present invention is not limited to the embodiments described above, and it goes without saying that various modifications are possible within the scope of the invention.
The present application claims priority based on Japanese Patent Application No. 2017-140506 filed on Jul. 20, 2017, and on Japanese Patent Application No. 2017-174582 filed on Sep. 12, 2017, and the contents of these applications are incorporated in their entirety by reference within this specification.
The exhaust device of the embodiments of the present invention can more reliably suppress wear of the coil spring.
EXPLANATION OF CODESSilencer 1; Baffle plate (partition plate) 9; Through hole (exhaust passage) 9b; Exhaust valve device 10, 110, 210, 310, 410; Valve seat 11; Support shaft 17; Valve body 20; Both side parts 22, 23; One flange 26; Collar member (cushion member) 29, 129, 229, 329A, 329B, 329C, 429D, 429E; Cylindrical part 29a, 229a; Semi-cylindrical part 129a; Flange part (weld part) 29b, 129b; Torsion coil spring (coil spring) 30; One end 31; Exhaust gas G; Clearance K;
Claims
1. An exhaust valve device comprising:
- a valve body placed in an exhaust passage in a silencer, and configured to open and close the exhaust passage;
- a valve seat against which the valve body abuts when the valve body is closed;
- a support shaft fixed to the valve seat, and supporting the valve body to be able to swing freely;
- a coil spring in which the support shaft is inserted, the coil spring biasing the valve body; and
- a cushion member interposed between the coil spring and the support shaft, the cushion member being rotatable relative to the support shaft.
2. The exhaust valve device of claim 1, wherein
- the cushion member is shorter than the support shaft, and interposed between the coil spring and the support shaft at one end part in an axial direction of the coil spring, at which the coil spring abuts the valve body.
3. The exhaust valve device of claim 1, wherein
- the cushion member is placed between a part of the coil spring that biases the valve body, and the support shaft, and is provided integrally with the valve body, and
- when opening and closing the valve body, the cushion member swings together with the valve body.
4. The exhaust valve device of claim 3, wherein
- the cushion member is spaced apart from the support shaft by a prescribed clearance.
5. The exhaust valve device of claim 3, wherein
- the cushion member is integrated with the valve body.
6. The exhaust valve device of claim 5, wherein
- the cushion member includes a cylindrical part in which the support shaft is inserted, and a flange part that is welded to the valve body.
7. The exhaust valve device of claim 5, wherein
- the cushion member includes a semi-cylindrical part in which the support shaft is inserted, and a flange part that is welded to the valve body.
8. The exhaust valve device of claim 3, wherein
- the cushion member is formed integrally with the valve body.
9. The exhaust valve device of claim 1, further comprising
- an additional cushion member interposed between the coil spring and the support shaft, the additional cushion member being rotatable relative to the support shaft, wherein
- each of the cushion member and the additional cushion member is cylindrical.
10. The exhaust valve device of claim 9, wherein
- one of the cushion member and the additional cushion member is provided between a part at which the coil spring biases the valve body, and the support shaft.
11. The exhaust valve device of claim 9, wherein
- each of the cushion member and the additional cushion member is spaced apart from the support shaft by a prescribed clearance.
Type: Application
Filed: Jul 19, 2018
Publication Date: May 21, 2020
Inventors: Katsufumi INOUE (Saitama-shi, Saitama), Hiroaki MASUBUCHI (Saitama-shi, Saitama), Yasunori KOZUKA (Saitama-shi, Saitama), Shou UCHIDA (Saitama-shi, Saitama), Youhei MAEZONO (Saitama-shi, Saitama), Mizuki HAYASHIDA (Saitama-shi, Saitama)
Application Number: 16/631,930