JP6211901B2 - Exhaust flow path valve device - Google Patents

Description

  The present invention relates to an exhaust passage valve device.

  2. Description of the Related Art There is known an exhaust flow path valve device that switches a flow path form by opening and closing an exhaust flow path in an exhaust system of an internal combustion engine. For example, Patent Document 1 describes a configuration in which an opening formed in a separator that partitions an internal combustion engine muffler into an upstream chamber and a downstream chamber is opened and closed by a valve device. In this valve device, the valve body capable of closing the opening is rotatably supported by the support body and is urged in the valve closing direction by the coil spring. For this reason, in the state where the rotation speed of the internal combustion engine is low, the pressure of the exhaust gas in the upstream chamber is low, so that the valve is closed with the opening closed by the valve body. On the other hand, when the number of rotations of the internal combustion engine increases, the pressure of the exhaust gas in the upstream chamber increases, and the valve body is separated from the opening portion and the valve opening state is opened.

  In the valve device described in Patent Document 1, when the valve body receives the pressure of the exhaust gas and opens against the urging force of the coil spring, the moment around the fulcrum shaft is proportional to the increase in the opening of the valve body. To increase. That is, the relationship between the load applied to the valve body and the opening of the valve body is linear. On the other hand, the structure by which the relationship between the load added to a valve body and the opening degree of a valve body is not linear is also proposed (refer patent document 2). That is, the valve device described in Patent Document 2 includes a spring that urges the valve body in the valve closing direction by an urging force in the extending direction between the valve body side action point and the fixed side action point. The fixed side action point is provided on the side opposite to the valve body with respect to the opening closed by the valve body. The fixed side action point is provided at a position where the moment around the support shaft of the valve body by the spring decreases as the opening of the valve body increases.

Japanese Patent Laid-Open No. 9-195749 Japanese Patent Laid-Open No. 2003-3820

  The exhaust flow valve device is required to have a noise reduction function for reducing noise by closing the valve in a state where the rotational speed of the internal combustion engine is low and the exhaust gas pressure is low, while the exhaust gas pressure is high because the rotational speed of the internal combustion engine is high. There is a need for a pressure loss reduction function that opens the valve in a high state to reduce pressure loss. However, in the valve device in which the spring acts on the valve body so that the relationship between the load applied to the valve body and the opening degree of the valve body is linear as in the configuration described in Patent Document 1 described above, the pressure of the exhaust gas is There was a problem that the valve body started to open from a low state.

  On the other hand, in the valve device in which the spring acts on the valve body so that the relationship between the load applied to the valve body and the opening degree of the valve body does not become linear as in the configuration described in Patent Document 2 described above, the initial load by the spring It is possible to increase (the urging force when the valve is closed). However, when the initial load by the spring is increased, the load on the spring is increased and the spring is quickly set. For this reason, when considering the product life, it is necessary to suppress the initial load by the spring to a certain level, and as a result, there may arise a problem that the valve body starts to open from a state where the pressure of the exhaust gas is low.

  An object of the present invention is to provide an exhaust flow path valve device capable of suppressing the opening of a valve body from a state where the pressure of exhaust gas is low.

  One aspect of the present invention is an exhaust flow path valve device, a support body, a valve body that is rotatably supported by the support body, opens and closes the exhaust flow path, and the valve body in a valve closing direction. A biasing member that biases, and a resistance member that engages the valve body at a valve closing position and generates resistance against rotational movement of the valve body from the valve closing position toward the valve opening direction. According to such a structure, it can suppress that a valve body begins to open from the state with the low pressure of waste gas.

  The said structure WHEREIN: The said resistance member is provided with the support side fixing | fixed part fixed to the said support body, and the valve side engaging part engaged with the said valve body in a valve closing position, The said valve side engaging part is The valve body may be elastically deformed with the rotational movement of the valve body from the valve closing position to the valve opening direction. According to such a structure, the structure which produces resistance with respect to the rotational movement can be implement | achieved simply, permitting the rotational movement of the valve body from a valve closing position to a valve opening direction. In addition, since the resistance member is fixed to the support body, the resistance member can be made difficult to be exposed to the exhaust gas as compared with the configuration in which the resistance member is fixed to the valve body.

  The said structure WHEREIN: The said valve side engaging part is the 1st inclination part which contact | abuts to the said valve body which rotationally moves to a valve opening direction, and the 2nd inclination part which contact | abuts to the said valve body which moves rotationally to a valve closing direction And an inclination angle of the first inclined portion with respect to a moving direction of the valve body in a state of being in contact with the first inclined portion is in the state of being in contact with the second inclined portion. It may be designed to be larger than the inclination angle of the second inclined portion with respect to the moving direction of the valve body. According to such a configuration, the resistance to the rotational movement of the valve body in the valve closing direction can be made smaller than the resistance to the rotational movement in the valve opening direction.

  The said structure WHEREIN: The said valve side engaging part may act on the front-end | tip part of the said valve body. According to such a configuration, variation in the effect due to individual differences (variations) in the resistance member is suppressed as compared with a configuration in which the valve-side engagement portion acts at a position closer to the rotation axis than the tip end portion of the valve body. be able to.

  In the above configuration, the resistance member includes a valve-side fixing portion fixed to the valve body, and a support-side engaging portion that engages with the support body at a valve-closing position, and the support-side engaging portion is The valve body may be elastically deformed with the rotational movement of the valve body from the valve closing position to the valve opening direction. According to such a structure, the structure which produces resistance with respect to the rotational movement can be implement | achieved simply, permitting the rotational movement of the valve body from a valve closing position to a valve opening direction.

  In the above configuration, the support side engaging portion includes a first inclined portion that contacts the support body when the valve body rotates in the valve opening direction, and when the valve body rotates in the valve closing direction. An inclination angle of the first inclined portion with respect to a relative movement direction of the support in a state in which the second inclined portion is in contact with the support. The tilt angle of the second inclined portion with respect to the relative movement direction of the support in a state of being in contact with the second inclined portion may be designed to be large. According to such a configuration, the resistance to the rotational movement of the valve body in the valve closing direction can be made smaller than the resistance to the rotational movement in the valve opening direction.

  The said structure WHEREIN: The said valve side fixing | fixed part may be fixed to the front-end | tip part of the said valve body. According to such a configuration, compared to a configuration in which the valve-side fixing portion is fixed at a position closer to the rotation axis than the distal end portion of the valve body, the variation in effect due to individual differences (variation) of the resistance members is suppressed. can do.

  The said structure WHEREIN: The said urging | biasing member may urge the said valve body in the valve closing direction with the force proportional to the opening degree of the said valve body. In such a configuration, there is a problem that the valve body starts to open from a state where the pressure of the exhaust gas is low, but such a problem can be made difficult to occur by the resistance member.

  In the above configuration, the biasing member may bias the valve body in the valve closing direction with a force that is not proportional to the opening of the valve body. Even in such a configuration, by suppressing the initial load to a certain level, there may be a problem that the valve body starts to open from a state where the exhaust gas pressure is low, but such a problem is caused by the resistance member. Can be difficult.

It is sectional drawing of a muffler. 2A is a perspective view of the valve device of the first embodiment in a closed state, FIG. 2B is a plan view thereof, and FIG. 2C is a sectional view thereof taken along IIC-IIC. FIG. 3A is a perspective view of the valve device according to the first embodiment in a valve open state, and FIG. 3B is a sectional view thereof. It is the schematic diagram which looked at the switch member from the side. 5A is a perspective view of the valve device of the first comparative example, FIG. 5B is a plan view thereof, and FIG. 5C is a sectional view of the VC-VC. FIG. 6A is a diagram showing the relationship between the opening degree and the load of the valve device of the first comparative example, and FIG. 6B is a diagram showing the relationship between the opening degree and the load of the valve device of the first embodiment. is there. 7A is a perspective view of the valve device according to the second embodiment in a closed state, FIG. 7B is a plan view thereof, and FIG. 7C is a sectional view of VIIC-VIIC thereof. FIG. 8A is a perspective view of the valve device according to the second embodiment in the opened state, and FIG. 8B is a sectional view thereof. 9A is a perspective view of the valve device of the second comparative example, FIG. 9B is a plan view thereof, and FIG. 9C is a sectional view of IXC-IXC thereof. FIG. 10A is a diagram showing the relationship between the opening degree and the load of the valve device of the second comparative example, and FIG. 10B is a diagram showing the relationship between the opening degree and the load of the valve device of the second embodiment. is there. 11A is a perspective view of the valve device of the third embodiment in a closed state, FIG. 11B is a plan view thereof, and FIG. 11C is a sectional view of the XIC-XIC. FIG. 12A is a perspective view of the valve device according to the third embodiment in the opened state, and FIG. 12B is a cross-sectional view thereof. 13A is a perspective view of a modified valve device in a closed state, FIG. 13B is a plan view thereof, and FIG. 13C is a side view thereof. FIG. 14A is a perspective view of the modified valve device in a valve-open state, and FIG. 14B is a side view thereof.

Embodiments to which the present invention is applied will be described below with reference to the drawings.
[1. First Embodiment]
[1-1. Constitution]
A muffler 1 shown in FIG. 1 constitutes a part of an exhaust passage of exhaust gas discharged from an internal combustion engine (not shown) mounted on a vehicle, and both end openings of a cylindrical shell member 11 are provided. The housing 10 is closed by the rear lid member 12 and the front lid member 13. The interior of the housing 10 is partitioned into three chambers, a first chamber 31, a second chamber 32, and a third chamber 33, by the first separator 21 and the second separator 22.

  The first chamber 31 is formed between the rear lid member 12 and the first separator 21. The second chamber 32 is formed between the first separator 21 and the second separator 22. The third chamber 33 is formed between the second separator 22 and the front lid member 13. The second separator 22 is formed with a communication hole 211 that allows the second chamber 32 and the third chamber 33 to communicate with each other.

  The muffler 1 also includes an inlet pipe 41 into which exhaust gas from the internal combustion engine is introduced. The inlet pipe 41 passes through the front lid member 13, the second separator 22, and the first separator 21, and is provided with its downstream end opened to the first chamber 31. A plurality of through holes 411 are formed on the outer peripheral surface of the inlet pipe 41 in the second chamber 32 to communicate the inner space of the inlet pipe 41 with the second chamber 32.

  Further, the muffler 1 includes an outlet pipe 42 that is connected to a tail pipe (not shown) and discharges exhaust gas. The outlet pipe 42 passes through the rear lid member 12, the first separator 21, and the second separator 22, and is provided with its upstream end opened to the third chamber 33.

  Further, the muffler 1 includes an inner pipe 43 that forms a communication channel that communicates the first chamber 31 and the third chamber 33. The inner pipe 43 passes through the first separator 21 and the second separator 22, and is provided with an upstream end opened to the first chamber 31 and a downstream end opened to the third chamber 33. However, in the third chamber 33, a valve device 100 for opening and closing an exhaust passage formed by the inner pipe 43 is attached to the downstream end portion of the inner pipe 43.

  As shown in FIGS. 2 (A) to 2 (C) and FIGS. 3 (A) to 3 (B), the valve device 100 of the first embodiment includes a stay 110, a butterfly 120, a coil spring 130, A pin 140 and a switch member 150 are provided. The valve device 100 is configured based on a valve device (so-called linear valve) in which the coil spring 130 acts on the butterfly 120 so that the relationship between the load applied to the butterfly 120 and the opening degree of the butterfly 120 is linear (proportional). Has been. However, as will be described later, in the valve device 100 of the present embodiment, the relationship between the load applied to the butterfly 120 and the opening degree of the butterfly 120 is not linear due to the action of the switch member 150.

  The stay 110 is fixed to the opening 431 at the downstream end of the inner pipe 43 (see FIG. 1). The stay 110 is formed with a communication hole 111 communicating with the opening 431 of the inner pipe 43, a shaft support 112 for supporting the butterfly 120 so as to be rotatable, and a fixed piece 113 to which the switch member 150 is joined. Has been.

  The butterfly 120 has a shape capable of closing the opening 431 of the inner pipe 43 (specifically, the communication hole 111 of the stay 110), and the base end 121 thereof is a shaft support portion of the stay 110 via the pin 140. 112. That is, the butterfly 120 is supported by the stay 110 so as to be rotatable about the rotation axis of the pin 140, and opens and closes an exhaust passage formed by the inner pipe 43 according to the rotational position.

  The coil spring 130 is attached in a state where the pin 140 is inserted so as to act on the stay 110 and the butterfly 120, and urges the butterfly 120 in the valve closing direction. Therefore, in a state where an external force for opening the butterfly 120 is not applied, the butterfly 120 is in a closed state (shown in FIGS. 2A to 2C) in which the exhaust flow path formed by the inner pipe 43 is closed. State).

  The switch member 150 is a member for causing the butterfly 120 to be engaged at the valve closing position and causing resistance to the rotational movement of the butterfly 120 from the valve closing position to the valve opening direction. Specifically, the switch member 150 is formed of a belt-like plate material made of a metal (for example, austenitic stainless steel) that can be elastically deformed. The switch member 150 includes a fixing portion 151 fixed to the stay 110 and an engaging portion 152 that engages with the butterfly 120 so as to prevent rotational movement of the butterfly 120 in the valve opening direction at the valve closing position. .

  The fixing portion 151 is joined (for example, welded) to the fixing piece 113 of the stay 110 formed so as to extend from the vicinity of the tip end portion 122 of the butterfly 120 at the valve closing position to the side opposite to the valve opening direction. For this reason, the engaging part 152 is disposed so as to act on the tip part 122 of the butterfly 120. Note that the tip portion 122 of the butterfly 120 means a portion farthest from the rotation axis of the pin 140.

  As shown in FIG. 4, the engaging portion 152 includes a first inclined portion 154 inclined with respect to the fixed portion 151, and a second inclined portion with respect to both the fixed portion 151 and the first inclined portion 154. The inclined portion 156 is formed. The fixed portion 151 and the first inclined portion 154 are continuous via the first bent portion 153. The first inclined portion 154 and the second inclined portion 156 are continuous via the second bent portion 155.

  The fixing portion 151 is disposed in a direction along the rotational movement direction (tangential direction) at the valve closing position of the butterfly 120 (direction perpendicular to the surface of the butterfly 120 at the valve closing position). On the other hand, the engaging portion 152 (the first inclined portion 154 and the second inclined portion 156) protrudes toward the butterfly 120 so as to interfere with the rotational movement path of the tip end portion 122 in the butterfly 120. Specifically, the first inclined portion 154 is disposed so as to contact the butterfly 120 that rotates and moves in the valve opening direction, and the second inclined portion 156 contacts the butterfly 120 that rotates and moves in the valve closing direction. Are arranged as follows.

  For this reason, the rotational movement of the butterfly 120 is hindered by the engaging portion 152, and the force required to elastically deform the engaging portion 152 so as to push it outward acts as a resistance against the rotational movement of the butterfly 120. This resistance increases as the inclination angle of the engaging portion 152 increases with respect to the moving direction of the distal end portion 122 of the butterfly 120 that contacts the engaging portion 152. The engaging portion 152 acts in the vicinity of the valve closing position of the butterfly 120. Therefore, the moving direction of the tip 122 of the butterfly 120 here can be approximated as the rotational movement direction (tangential direction) at the valve closing position of the butterfly 120, in other words, the direction of the fixed portion 151.

  In the present embodiment, the resistance to the rotational movement of the butterfly 120 in the valve opening direction is configured to be larger than the resistance to the rotational movement in the valve closing direction. Specifically, the butterfly in the state where the inclination angle θ1 of the first inclined portion 154 with respect to the moving direction of the butterfly 120 in the state of contact with the first inclined portion 154 is in contact with the second inclined portion 156 is used. It is designed to be larger than the inclination angle θ2 of the second inclined portion 156 with respect to the moving direction of 120 (θ1> θ2). The resistance due to the inclination angle θ2 is designed to be small enough to allow the butterfly 120 to return to the valve closing position by the biasing force of the coil spring 130.

[1-2. Action]
Next, the operation of the valve device 100 will be described. As shown by arrows in FIG. 1, exhaust gas from the internal combustion engine is introduced into the second chamber 32 through a plurality of through holes 411 formed in the inlet pipe 41, and is silenced by an expansion / resonance effect. Thereafter, the exhaust gas in the second chamber 32 is introduced into the third chamber 33 through the communication hole 211 formed in the second separator 22 and further silenced by the expansion / resonance effect. Thus, the exhaust gas in the third chamber 33 in which the pressure pulsation is smoothed and silenced is discharged to the outside through the outlet pipe 42.

  In a state where the rotational speed of the internal combustion engine is low, the pressure of the exhaust gas is low, and the pressure difference between the first chamber 31 and the third chamber 33 is small. In this state, the acting force exerted on the butterfly 120 by the pressure in the first chamber 31 is smaller than the acting force exerted on the butterfly 120 by the load by the coil spring 130, the engaging force by the engaging portion 152, and the pressure in the third chamber 33. Accordingly, the opening 431 of the inner pipe 43 is closed by the butterfly 120.

  On the other hand, when the rotational speed of the internal combustion engine increases and the pressure of the exhaust gas increases, the acting force exerted on the butterfly 120 by the pressure in the first chamber 31 includes the load by the coil spring 130, the engagement force by the engagement portion 152, and the third chamber. The pressure in 33 becomes larger than the acting force exerted on the butterfly 120. As a result, the butterfly 120 is opened, and the first chamber 31 and the third chamber 33 are communicated with each other via the inner pipe 43. Thereafter, when the rotational speed of the internal combustion engine decreases and the pressure of the exhaust gas becomes low, the butterfly 120 is closed and the opening 431 of the inner pipe 43 is closed by the butterfly 120.

[1-3. effect]
According to the first embodiment described in detail above, the following effects can be obtained.
[1A] The valve device 100 according to the first embodiment includes the switch member 150 that engages the butterfly 120 at the valve closing position and generates resistance against the rotational movement of the butterfly 120 from the valve closing position to the valve opening direction. . Therefore, according to the valve apparatus 100, it can suppress that the butterfly 120 begins to open from the state with the low pressure of waste gas.

  Such an effect will be described in comparison with the valve device 600 of the first comparative example shown in FIGS. 5 (A) to 5 (C). The valve device 600 is different from the valve device 100 of the first embodiment in that it does not mainly include the switch member 150.

  As shown in FIG. 6A, in the valve device 600 of the first comparative example, the opening degree and the load are proportional, and the butterfly 120 starts to open from a state where the pressure of the exhaust gas is low. On the other hand, in the valve device 100 of the first embodiment, as indicated by a solid line in FIG. 6B, the load necessary for rotating the butterfly 120 from the valve closing position to the valve opening direction is the switch member 150. Increased by the action of As a result, according to the valve device 100, the butterfly 120 can be prevented from opening from a state where the pressure of the exhaust gas is low. Further, as indicated by a broken line in FIG. 6B, an increase in the load necessary for rotating the butterfly 120 in the valve closing direction is suppressed, so that the butterfly 120 is moved to the valve closing position by the urging force of the coil spring 130. You can go back up.

  [1B] The switch member 150 includes a fixing portion 151 fixed to the stay 110, and an engaging portion 152 that engages the butterfly 120 so as to prevent rotational movement of the butterfly 120 in the valve opening direction at the valve closing position. Prepare. Then, the engaging portion 152 is elastically deformed so as to be pushed away by the butterfly 120 with the rotational movement of the butterfly 120 from the valve closing position to the valve opening direction. Therefore, according to the valve apparatus 100, the structure which produces resistance with respect to the rotational movement can be implement | achieved simply, accept | permitting the rotational movement of the butterfly 120 from the valve closing position to the valve opening direction. In addition, since the switch member 150 is fixed to the stay 110, the switch member 150 can be less exposed to the exhaust gas than the configuration in which the switch member 150 is fixed to the butterfly 120.

  [1C] The engaging portion 152 includes a first inclined portion 154 that contacts the butterfly 120 that rotates and moves in the valve opening direction, and a second inclined portion 156 that contacts the butterfly 120 that rotates and moves in the valve closing direction. Prepare. Then, the inclination angle θ1 of the first inclined portion 154 with respect to the moving direction of the butterfly 120 in the state of contact with the first inclined portion 154 is the movement of the butterfly 120 in the state of being in contact with the second inclined portion 156. It is designed to be larger than the inclination angle θ2 of the second inclined portion 156 with respect to the direction. Therefore, according to the valve device 100, the resistance to the rotational movement of the butterfly 120 in the valve closing direction can be made smaller than the resistance to the rotational movement in the valve opening direction.

  [1D] The engaging portion 152 acts on the distal end portion 122 of the butterfly 120. Therefore, according to the valve device 100, the effect due to the individual difference (variation) of the switch member 150 is less than that in the configuration in which the engaging portion 152 acts at a position closer to the rotation axis than the tip end portion 122 of the butterfly 120. Can be suppressed.

  In the first embodiment, the valve device 100 corresponds to an example of a valve device for an exhaust passage, the stay 110 corresponds to an example of a support body, the butterfly 120 corresponds to an example of a valve body, and a coil spring 130 is attached. The switch member 150 corresponds to an example of a biasing member, and the switch member 150 corresponds to an example of a resistance member. The fixing portion 151 corresponds to an example of a support side fixing portion, the engaging portion 152 corresponds to an example of a valve side engaging portion, the first inclined portion 154 corresponds to an example of a first inclined portion, The second inclined portion 156 corresponds to an example of a second inclined portion.

[2. Second Embodiment]
[2-1. Constitution]
Since the basic configuration of the second embodiment is the same as that of the first embodiment, the same reference numerals are used for common configurations, and differences will be mainly described.

  As shown in FIGS. 7A to 7C and FIGS. 8A to 8B, the valve device 200 according to the second embodiment includes a stay 210, a butterfly 220, a leaf spring 230, and the like. The pin 240 and the switch member 150 are provided. Since the shape, material, function, and the like of the switch member 150 are the same as those in the first embodiment, a specific description thereof is omitted. The valve device 200 is based on a valve device (so-called non-linear valve) in which the leaf spring 230 acts on the butterfly 220 so that the relationship between the load applied to the butterfly 220 and the opening degree of the butterfly 220 is not linear (not proportional). It is configured. Specifically, the nonlinear valve is designed so that the load takes a peak value at the opening before the butterfly 220 reaches the maximum opening.

  The stay 210 is fixed to the opening 431 at the downstream end of the inner pipe 43, as in the stay 110 of the first embodiment. The stay 210 includes a communication hole 211 that communicates with the opening 431 of the inner pipe 43, a shaft support 212 that supports the butterfly 220 so as to be rotatable, a fixing piece 213 to which the switch member 150 is joined, a leaf spring A support portion 214 for supporting one end of 230 is formed.

  The butterfly 220 has a shape capable of closing the opening 431 of the inner pipe 43 (specifically, the communication hole 211 of the stay 210), and the base end portion 221 thereof is a shaft support portion of the stay 210 via the pin 240. 212. That is, the butterfly 220 is supported by the stay 210 so as to be rotatable about the rotation axis of the pin 240, and opens and closes an exhaust passage formed by the inner pipe 43 according to the rotational position.

  The leaf spring 230 acts on the stay 210 and the butterfly 220 with one end supported by the support portion 214 of the stay 210 and the other end supported by the tip portion 222 of the butterfly 220, and attaches the butterfly 220 in the valve closing direction. Rush. Therefore, in the state where the external force for opening the butterfly 220 is not applied, the butterfly 220 closes the exhaust flow path formed by the inner pipe 43 (shown in FIGS. 7A to 7C). State).

[2-2. effect]
According to the second embodiment described in detail above, the following effects are obtained in addition to the effects [1B] to [1D] of the first embodiment described above.

  [2A] The valve device 200 of the second embodiment includes the switch member 150 that engages the butterfly 220 at the valve closing position and generates resistance against the rotational movement of the butterfly 220 from the valve closing position to the valve opening direction. . Therefore, according to the valve apparatus 200, it can suppress that the butterfly 220 begins to open from the state with the low pressure of waste gas.

  Such an effect will be described in comparison with the valve device 700 of the second comparative example shown in FIGS. 9 (A) to 9 (C). The valve device 700 is different from the valve device 200 of the second embodiment in that it mainly does not include the switch member 150.

  As shown by a broken line in FIG. 10A, in the valve device 700 of the second comparative example, it is possible to increase the initial load by the leaf spring 230, but if the initial load is increased, the load on the leaf spring 230 is increased. Increases and the settling of the leaf spring 230 is accelerated. For this reason, as indicated by a solid line in FIG. 10A, it is necessary to suppress the initial load by the leaf spring 230 to a certain level, and as a result, the butterfly 220 starts to open from a state where the exhaust gas pressure is low. On the other hand, in the valve device 200 of the second embodiment, as indicated by a solid line in FIG. 10B, the load necessary for rotating the butterfly 220 from the valve closing position to the valve opening direction is the switch member 150. Increased by the action of As a result, according to the valve device 200, the butterfly 220 can be prevented from opening from a state where the pressure of the exhaust gas is low. Further, as indicated by a broken line in FIG. 10B, since an increase in load necessary for rotating the butterfly 220 in the valve closing direction is suppressed, the butterfly 220 is closed by the biasing force of the leaf spring 230. It can be returned to the position.

  In the second embodiment, the valve device 200 corresponds to an example of an exhaust flow path valve device, the stay 210 corresponds to an example of a support, the butterfly 220 corresponds to an example of a valve body, and the leaf spring 230 includes It corresponds to an example of an urging member.

[3. Third Embodiment]
[3-1. Constitution]
Since the basic configuration of the third embodiment is the same as that of the first embodiment, the same reference numerals are used for the common configurations, and differences will be mainly described.

  As shown in FIGS. 11 (A) to 11 (C) and FIGS. 12 (A) to 12 (B), the valve device 300 of the third embodiment includes a stay 310, a butterfly 320, a coil spring 130, A pin 140 and a switch member 150 are provided.

The basic structure of the stay 310 is the same as that of the stay 110 of the first embodiment, and is different in that the fixed piece 113 is not provided.
The butterfly 320 has the same basic configuration as the butterfly 120 of the first embodiment, and is different in that a fixed piece 323 to which the switch member 150 is joined is formed at the distal end portion 322.

  The switch member 150 is the same as that of the first embodiment, but is different in that the fixing portion 151 is fixed to the fixing piece 323 of the butterfly 320 and the engaging portion 152 engages with the stay 310. That is, in the third embodiment, the switch member 150 is provided in the opposite direction to the first embodiment. Specifically, the fixing portion 151 is joined (for example, welded) to a fixing piece 323 of the butterfly 320 formed so as to extend from the tip portion 322 of the butterfly 320 to the side away from the stay 310.

  The fixed portion 151 is disposed in a direction along the rotational movement direction (tangential direction) at the valve closing position of the butterfly 320. On the other hand, the engaging portion 152 (the first inclined portion 154 and the second inclined portion 156) protrudes toward the stay 310 so as to interfere with the relative rotational movement path of the stay 310 with respect to the butterfly 320. Specifically, the first inclined portion 154 is disposed so as to come into contact with the distal end portion 314 of the stay 310 when the butterfly 320 rotates in the valve opening direction. Further, the second inclined portion 156 is disposed so as to abut on the tip portion 314 of the stay 310 when the butterfly 320 rotates in the valve closing direction.

  For this reason, the relative rotational movement of the stay 310 with respect to the butterfly 320 (that is, the rotational movement of the butterfly 320) is prevented by the engaging portion 152. The force required to elastically deform the engaging portion 152 so as to push it outward acts as a resistance against the rotational movement of the butterfly 320. Specifically, as in the first embodiment, the resistance to the rotational movement of the butterfly 320 in the valve opening direction is configured to be larger than the resistance to the rotational movement in the valve closing direction. That is, the inclination angle θ1 of the first inclined portion 154 with respect to the relative movement direction of the stay 310 in the state of contact with the first inclined portion 154 is the stay in the state of being in contact with the second inclined portion 156. It is designed to be larger than the inclination angle θ2 of the second inclined portion 156 with respect to the relative movement direction of 310 (θ1> θ2).

[3-2. effect]
According to the third embodiment described in detail above, the following effect is obtained in addition to the effect [1A] of the first embodiment described above.

  [3A] The switch member 150 includes a fixing portion 151 fixed to the butterfly 320, and an engaging portion 152 that engages with the stay 310 so as to prevent rotational movement of the butterfly 320 in the valve opening direction at the valve closing position. Prepare. The engaging portion 152 is elastically deformed so as to be pushed away by the stay 310 with the rotational movement of the butterfly 320 from the valve closing position to the valve opening direction. Therefore, according to the valve device 300, it is possible to easily realize a configuration in which the rotational movement of the butterfly 320 from the valve closing position in the valve opening direction is allowed and resistance is generated with respect to the rotational movement.

  [3B] The engaging portion 152 contacts the first inclined portion 154 that contacts the stay 310 when the butterfly 320 rotates in the valve opening direction, and the stay 310 when the butterfly 320 rotates in the valve closing direction. A second inclined portion 156 in contact therewith. The inclination angle θ1 of the first inclined portion 154 with respect to the relative movement direction of the stay 310 in the state of being in contact with the first inclined portion 154 is the stay in the state of being in contact with the second inclined portion 156. It is designed to be larger than the inclination angle θ2 of the second inclined portion 156 with respect to the relative movement direction of 310. Therefore, according to the valve device 300, the resistance to the rotational movement of the butterfly 320 in the valve closing direction can be made smaller than the resistance to the rotational movement in the valve opening direction.

  [3C] The fixing portion 151 is fixed to the tip portion 322 of the butterfly 320. Therefore, according to the valve device 300, as compared with the configuration in which the fixing portion 151 is fixed at a position closer to the rotation axis than the tip end portion 122 of the butterfly 320, the variation due to the individual difference (variation) of the switch member 150 is varied. Can be suppressed.

  In the third embodiment, the valve device 300 corresponds to an example of an exhaust passage valve device, the stay 310 corresponds to an example of a support body, and the butterfly 320 corresponds to an example of a valve body. The fixing portion 151 corresponds to an example of a valve side fixing portion, the engaging portion 152 corresponds to an example of a support side engaging portion, the first inclined portion 154 corresponds to an example of a first inclined portion, The second inclined portion 156 corresponds to an example of a second inclined portion.

[4. Other Embodiments]
As mentioned above, although embodiment of this invention was described, it cannot be overemphasized that this invention can take a various form, without being limited to the said embodiment.

  [4A] In the third embodiment, the configuration in which the switch member 150 is fixed to the butterfly 320 side is illustrated based on the configuration of the first embodiment. However, the configuration is not limited thereto. For example, the switch member 150 may be fixed to the butterfly 220 side based on the configuration of the second embodiment.

  [4B] In the above embodiment, the configuration in which the resistance member acts on the tip of the support body or the valve body is exemplified, but the configuration is not limited to this, and the construction acts on the position closer to the rotation axis than the tip. It is good. For example, the valve device 400 of the modification shown in FIGS. 13 (A) to 13 (C) and FIGS. 14 (A) to 14 (B) has the same basic configuration as the valve device 100 of the first embodiment. This is different in that the switch member 150 is provided at a position near the rotation axis of the butterfly 120. Even if it is such a structure, it can suppress that the butterfly 120 begins to open from the state where the pressure of waste gas is low.

  [4C] In the above embodiment, a configuration in which a so-called linear valve or nonlinear valve is provided with a resistance member (switch member 150) is exemplified. However, a valve device (valve device to which the present invention can be applied) serving as a base is other than these. It may be a configuration.

  [4D] In the above embodiment, the configuration in which the valve device is attached to the downstream end portion of the inner pipe 43 is illustrated, but the attachment position of the valve device is not limited to this. For example, a through hole may be formed in the second separator 22 and a valve device may be attached to the through hole.

  [4E] The functions of one component in the above embodiment may be distributed as a plurality of components, or the functions of a plurality of components may be integrated into one component. Further, at least a part of the configuration of the above embodiment may be replaced with a known configuration having the same function. Moreover, you may abbreviate | omit a part of structure of the said embodiment as long as a subject can be solved. In addition, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified from the wording described in the claims are embodiments of the present invention.

  [4F] In addition to the valve device described above, the present invention can be realized in various forms such as an exhaust system and an exhaust method using the valve device as components.

  100, 200, 300, 400 ... valve device, 110, 210, 310 ... stay, 120, 220, 320 ... butterfly, 130 ... coil spring, 150 ... switch member, 151 ... fixing part, 152 ... engaging part, 153 ... first 1 bent portion, 154... First inclined portion, 155... Second bent portion, 156... Second inclined portion, 230.

Claims (6)

A support;
A valve body that is rotatably supported by the support body, and that opens and closes an exhaust passage;
A biasing member that biases the valve body in a valve closing direction;
A resistance member that engages the valve body at a valve closing position, and generates resistance against the rotational movement of the valve body in the valve opening direction from the valve closing position;
Equipped with a,
The resistance member is
A support side fixing portion fixed to the support;
A valve side engaging portion that engages with the valve body in a valve closing position;
With
The valve side engaging portion is
Elastically deformed with the rotational movement of the valve body from the valve closing position to the valve opening direction,
A first inclined portion that contacts the valve body that rotates and moves in the valve opening direction;
A second inclined portion that contacts the valve body that rotates and moves in a valve closing direction;
With
The inclination angle of the first inclined portion with respect to the moving direction of the valve body in a state in contact with the first inclined portion is the moving direction of the valve body in a state in contact with the second inclined portion. compared to the inclination angle of the second inclined portion with respect to, that is largely designed
An exhaust flow path valve device. It is the valve device for exhaust passages according to claim 1 ,
The valve-side engaging portion acts on a tip portion of the valve body. A support;
A valve body that is rotatably supported by the support body, and that opens and closes an exhaust passage;
A biasing member that biases the valve body in a valve closing direction;
A resistance member that engages the valve body at a valve closing position, and generates resistance against the rotational movement of the valve body in the valve opening direction from the valve closing position;
Equipped with a,
The resistance member is
A valve side fixing portion fixed to the valve body;
A support side engaging portion that engages with the support in the valve-closed position;
With
The support side engaging portion is
Elastically deformed with the rotational movement of the valve body from the valve closing position to the valve opening direction,
A first inclined portion that contacts the support when the valve body rotates in the valve opening direction;
A second inclined portion that contacts the support when the valve body rotates in the valve closing direction;
With
The support body in a state in which an inclination angle of the first inclined portion with respect to a relative movement direction of the support body in contact with the first inclined portion is in contact with the second inclined portion. compared relative inclination angle of the second inclined portion with respect to the direction of movement of the, that are largely designed
An exhaust flow path valve device. It is the valve device for exhaust passages according to claim 3 ,
The valve-side fixing portion is fixed to a distal end portion of the valve body. It is the valve device for exhaust passages according to any one of claims 1 to 4 ,
The urging member urges the valve body in a valve closing direction with a force proportional to the opening of the valve body. It is the valve device for exhaust passages according to any one of claims 1 to 4 ,
The urging member urges the valve body in a valve closing direction with a force that is not proportional to the opening of the valve body.

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