JP5616661B2 - Exhaust flow control valve - Google Patents

Description

  The present invention relates to an exhaust flow rate control valve provided in an exhaust passage of an internal combustion engine (engine) and capable of controlling the flow rate of exhaust gas flowing through the exhaust passage.

  Conventionally, for example, an on-off valve is disposed in an exhaust passage of an automobile engine, and the flow rate of exhaust gas flowing through the exhaust passage is controlled by the on-off valve urged in the valve closing direction by an elastic member. Has been done. As an exhaust flow control valve of this type, for example, Patent Document 1 discloses a plate in which a plurality of concave grooves are formed as a fixing member that locks a fixed arm (fixed end) of a torsion coil spring that is an elastic member. An exhaust flow control valve is disclosed in which the torsion coil spring can be arbitrarily set by engaging and locking a fixed arm of the torsion coil spring with a selected concave groove.

  Further, in Patent Document 2, a torsion coil spring that biases the open / close valve toward the closing side is disposed in a space formed between the outer pipe of the exhaust pipe and the recess of the inner pipe. An exhaust flow control valve is disclosed in which a fixed arm (fixed end) is locked by a locking piece fixed to an inner pipe.

JP 2007-205180 A JP 2006-322357 A

  By the way, in the exhaust flow control valve disclosed in Patent Document 1, it is necessary to provide a plate for locking the fixed side arm that is a fixed end of the torsion coil spring, and to weld the plate to the side wall of the inner tube. Become. Further, in the exhaust flow control valve disclosed in Patent Document 2, it is necessary to provide a locking piece for locking the stationary arm of the torsion coil spring and fix the locking piece to the side wall of the inner tube.

  As described above, in the exhaust flow control valve disclosed in Patent Document 1 and Patent Document 2, a special member (for example, a plate or a locking piece) for fixing the fixed end of the torsion coil spring is required, and the number of parts is reduced. And the weight of the entire apparatus increases, and an operation for fixing the fixing member is required, which increases the manufacturing cost.

  The present invention has been made in view of the above points, and eliminates the need for a special member for fixing the fixed end of the torsion coil spring, thereby reducing the number of components and reducing the manufacturing cost. An object is to provide a control valve.

In order to achieve the above-mentioned object, the present invention is provided in an exhaust system that exhausts exhaust gas discharged from an internal combustion engine to the outside, and the flow rate of the exhaust gas flowing through the exhaust passage is controlled by opening and closing the valve body. In the exhaust flow control valve to be controlled, a valve body, a torsion coil spring that urges the valve body disposed inside the valve body to a valve closed state, and is pivotally supported by the valve body, A valve shaft connected to the valve body and rotating integrally with the valve body, and an urging force transmission mechanism connected to the movable end of the torsion coil spring and transmitting the spring force of the torsion coil spring to the valve body The valve shaft is provided with a locking portion that locks the fixed end of the torsion coil spring, and the torsion coil spring closes the valve body through the biasing force transmission mechanism. The urging force transmission mechanism and the fixed And is characterized by Rukoto is connected to the valve shaft.

According to the present invention, the locking portion is provided on the valve shaft serving as the pivot point of the valve body, and the fixed end of the torsion coil spring is locked by the locking portion. A member (for example, a plate, a locking piece, etc.) becomes unnecessary, and can reduce a number of parts and can reduce manufacturing cost. In addition, as a latching | locking part provided in a valve shaft, it can manufacture easily by forming a groove part in the outer peripheral surface of a valve shaft, for example. Further, an urging force transmission mechanism connected to the movable end of the torsion coil spring and transmitting the spring force of the torsion coil spring to the valve body is provided. The urging force transmission mechanism and the fixed end are connected to the valve shaft, respectively. Yes.
Further, the present invention is characterized in that the locking portion is provided on the lower side of the valve shaft.
According to the present invention, the fixed end of the torsion coil spring is locked to the lower side of the valve shaft, so that the fixed end can be suitably prevented from being displaced upward by the spring force. .
Furthermore, the present invention is characterized in that a partition wall member is interposed between the urging force transmission mechanism and the fixed end.
According to the present invention, the partition member (see, for example, the C clip 76 of the embodiment) is interposed between the urging force transmission mechanism and the fixed end, so that the non-contact state between the urging force transmission mechanism and the fixed end is preferable. Retained.
Furthermore, in the present invention, the valve body has a recess that is recessed toward the inside of the valve body, and the biasing force transmission mechanism and the fixed end are located on the valve shaft at a position corresponding to the recess. It is connected.
According to the present invention, the biasing force transmission mechanism and the fixed end are connected to the valve shaft at a position corresponding to the recess, so that various members can be arranged close to the vicinity of the valve shaft and integrated. Thus, space saving can be achieved.

  In the present invention, a special member for fixing the fixed end of the torsion coil spring is not required, and the exhaust flow rate control valve capable of reducing the number of parts and reducing the manufacturing cost can be obtained.

FIG. 3 is an exploded perspective view in which an exhaust flow control valve according to an embodiment of the present invention is incorporated in an exhaust system of an automobile engine and a cover member is removed from the exhaust flow control valve. (A) is a schematic perspective view of the exhaust flow control valve in which the cover member is omitted, and (b) is a longitudinal sectional view taken along line II-II in (a). (A) is the perspective view seen from the diagonal direction of the front side, (b) is the transparent perspective view seen from the diagonal direction of the rear side. It is a principal part disassembled perspective view which abbreviate | omitted the inner pipe | tube. It is a side perspective view which shows the positional relationship of a spring mechanism and a valve body. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. It is operation | movement explanatory drawing of the exhaust flow control valve which concerns on this embodiment, Comprising: (a) shows the valve closed state of a valve body, (b) and (c) have shown the valve open state of the valve body. .

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is an exploded perspective view in which an exhaust flow control valve according to an embodiment of the present invention is incorporated in an exhaust system of an automobile engine, and a cover member is removed from the exhaust flow control valve.

  As shown in FIG. 1, the exhaust system 10 is connected to an exhaust port of an automobile engine (internal combustion engine) (not shown) and is provided so as to extend along the front-rear direction of the automobile 11. A first silencer 12, a pair of second silencers 14a and 14b, and a pair of third silencers 16a and 16b are disposed along the downstream side from the upstream side of the exhaust system 10, respectively. The third silencers 12, 14a, 14b, 16a, 16b are integrally connected via a plurality of pipe members. An exhaust flow control valve 30 according to an embodiment of the present invention is provided in front of the second silencers 14a and 14b and on the output side of the first silencer 12.

  In the present embodiment, the exhaust system 10 in which the exhaust flow control valve 30 is disposed between the first silencer 12 and the second silencers 14a and 14b is illustrated, but the present invention is not limited to this. The exhaust flow control valve 30 may be disposed at another part of the exhaust system 10.

  2A is a schematic perspective view of an exhaust flow control valve in which a cover member is omitted, FIG. 2B is a longitudinal sectional view taken along line II-II in FIG. 2A, and FIG. FIG. 3B is a perspective view seen from the front oblique direction, FIG. 3B is a perspective view seen from the rear oblique direction, FIG. 4 is an exploded perspective view of the main part with the inner tube omitted, and FIG. FIG. 6 is a side perspective view showing the positional relationship between the spring mechanism and the valve body, and FIG. 6 is a cross-sectional view taken along line VI-VI in FIG.

  As shown in FIG. 2, the exhaust flow control valve 30 has an inlet port 32a connected to the first silencer 12 and an outlet port 32b connected to a branched pipe member on the second silencer 14a, 14b side. An inner pipe (valve body) 34 to be formed, and a pair of cover members 36a and 36b (see FIG. 1) that are formed of a rectangular body formed in a pair of upper and lower parts and surround the inner pipe 34 are included.

  The inner tube 34 is formed of a substantially oval cylindrical body in which a through hole 38 is formed. The inner tube 34 is an intermediate portion of the inner tube 34 along the inlet port 32a and the outlet port 32b, and the inner tube 34 is perpendicular to the axis. Concave portions 40 that are recessed inward are formed on both sides.

  Further, as shown in FIG. 3, the inner pipe 34 includes a valve mechanism 44 having a valve body 42 for controlling the flow rate of exhaust gas introduced from the inlet port 32a and led out from the outlet port 32b, and the valve A spring mechanism 48 including a torsion coil spring (coil spring) 46 that urges the body 42 to the valve closed state, and an urging force (spring force) of the torsion coil spring 46 that urges the valve body 42 toward the valve closed state. ) Is transmitted to the valve body 42. The urging force (spring force) of the torsion coil spring 46 refers to a force that causes the valve body 42 to rotate in a direction in which the valve body 42 abuts against the stopper member 60 with a valve shaft 52 described later as a rotation fulcrum.

  The valve mechanism 44 extends in a direction orthogonal to the axis connecting the inlet port 32a and the outlet port 32b, and is pivotally supported through a pair of support holes so as to pass through both side portions of the inner tube 34. The shaft 52 and a valve body 42 made of a rectangular plate body as viewed from the axial direction of the inner pipe 34 (see FIG. 2B) and provided so as to be rotatable at a predetermined angle with the valve shaft 52 as a fulcrum, And a weight member 56 fixed to a portion in the vicinity of one long side of the rectangular valve body 42.

  In this case, the valve shaft 52 is provided with a connecting portion 52a that extends along the axial direction and is formed by cutting out a part of the outer periphery in a planar shape (FIG. 3B, FIG. 4, FIG. 6). The other long side vicinity part of the valve body 42 which consists of a rectangular-shaped board body is fixed to the valve shaft 52 via the screw member 58 by making the said connection part 52a into a mating surface. Further, an annular flange portion 52b that protrudes along the radially outward direction is provided on one end portion side of the valve shaft 52.

  Further, the valve mechanism 44 is composed of a member having a substantially L-shaped cross section fixed to the inner wall of the inner pipe 34, and a valve member 42 which comes into contact with the valve member 42 to be in a closed state. A buffer member 62 that cushions an impact when the body 42 abuts against the stopper member 60, and a metal that is provided on both sides of the valve shaft 52 and outside the inner tube 34, and rotatably supports the valve shaft 52. A bearing member 64 made of a mesh is provided, and a ring body 66 for preventing deformation of the bearing member 64 (see FIG. 6). When the valve body 42 is in the valve closed state in contact with the stopper member 60, it is formed by a gap 67 between the inner wall of the inner tube 34 and the outer surface of the valve body 42 as shown in FIG. The exhaust gas passage area is the most constricted (minimum area).

  Both end portions of the valve shaft 52 projecting outward from the inner tube 34, the torsion coil spring 46, and the like are disposed in a recess 40 that is recessed inwardly outside the inner tube 34 formed of a substantially elliptical cylindrical body. (See FIGS. 2 and 6). For this reason, even if the inner pipe 34 is covered with the pair of upper and lower cover members 36a and 36b, the torsion coil spring 46 and the like do not get in the way, and the exhaust flow control valve 30 in a state where the cover members 36a and 36b are mounted. The overall shape is configured in a substantially rectangular parallelepiped shape.

  As shown in FIG. 6, the spring mechanism 48 includes a torsion coil spring 46, and the torsion coil spring 46 includes a coil portion 46 a formed of a substantially cylindrical spiral body and a coil portion 46 a that is separated from the inner tube 34. A fixed side arm 46b which is provided on one side and extends in a direction substantially orthogonal to the axial direction of the coil part 46a and which is a fixed end; and the coil part provided on the other side of the coil part 46a adjacent to the inner tube 34 The movable arm 46c includes a movable end that extends in a direction substantially orthogonal to the axial direction of 46a.

  Further, the spring mechanism 48 is fixed to the outer wall of the intermediate portion along the axial direction of the inner tube 34 by welding or the like, and is fixed to the plate 68 having a rectangular shape when viewed from the side, and the torsion coil spring 46. A cylindrical support member 70 that supports the coil portion 46 a from the inner peripheral side and a bolt 71 that is screwed into a screw hole of the support member 70 are attached to the support member 70, and And a disc-shaped pressing plate 72 that prevents the torsion coil spring 46 from being detached. In the present embodiment, the shape of holding the coil portion 46a of the torsion coil spring 46 from the inner peripheral side is illustrated as the support member 70, but the shape is not limited to this, for example, the outer wall of the inner tube 34 The outer peripheral surface of the coil portion 46a may be gripped by a curved portion formed in a substantially Ω shape when viewed from the side.

  In this case, a portion of the support member 70 adjacent to the plate 68 is provided with a deformation absorbing portion 73 formed by cutting a part of the outer peripheral surface along the axial direction into a substantially arc shape in cross section. . When the deformation absorbing portion 73 tries to switch from the valve closed state (initial state) in which the valve body 42 contacts the stopper member 60 to the valve open state due to the pressure of the exhaust gas flowing through the inner pipe 34, A force (compression force) applied to the coil portion 46a of the torsion coil spring 46 through the movable arm 46c is absorbed.

As shown in FIGS. 2 to 6, the biasing force transmission mechanism 50 is formed on one end side along the axial direction of the valve shaft 52 exposed to the outside from the inner tube 34, and from the fixed end of the torsion coil spring 46. An annular groove (groove portion) 74 to which the fixed arm 46b is locked, a C clip (partition wall member) 76 attached to an annular step portion adjacent to the annular groove 74, and a movable end of the torsion coil spring 46 A sphere 78 mounted to be able to roll on the bending portion 46d of the movable arm 46c, and a holding surface 80a for holding the sphere 78 in a point contact state at one end and a linear intermediate portion continuous to the one end. And a stay member 80 having a substantially arc-shaped fixed portion 80b fixed to the valve shaft 52 at the other end and rotating integrally with the valve shaft 52 with the valve shaft 52 as a fulcrum.

  The annular groove 74 functions as a locking portion (groove portion) that locks the fixed end of the torsion coil spring 46. In the present embodiment, the annular groove 74 is formed to circulate along the outer peripheral surface of the valve shaft 52. However, the present invention is not limited to this. For example, the annular groove 74 may be formed by a flat surface or a recess formed by cutting out the lower side of the outer surface of the valve shaft 52 with a flat surface. . A disc member 82 is fixed to the other end portion along the axial direction of the valve shaft 52 through a hole portion, and the disc member 82 prevents the valve shaft 52 from coming off from the support hole of the inner pipe 34. Is made.

  In this case, as shown in FIG. 6, a fixed side arm 46 b of the torsion coil spring 46 that is locked in the annular groove 74 of the valve shaft 52 and a fixed portion 80 b of the stay member 80 that is fixed to the valve shaft 52. A C clip 76 is interposed therebetween, and the C clip 76 functions as a partition wall, so that the non-contact state between the fixing portion 80b of the stay member 80 and the fixing side arm 46b of the torsion coil spring 46 is preferably maintained. Is done. As a result, even if the stationary arm 46 of the torsion coil spring 46 is locked by the annular groove 74 of the valve shaft 52, the smooth rotation operation of the stay member 80 that rotates integrally with the valve shaft 52 is achieved. Can be secured.

  The C clip 76 prevents the stationary arm 46 b of the torsion coil spring 46 locked in the annular groove 74 of the valve shaft 52 from moving toward the stay member 80 along the axial direction of the valve shaft 52. It also has a stopper function. Further, an annular flange portion 52b is interposed between the fixed portion 80b of the stay member 80 fixed to the valve shaft 52 and the bearing member 64, so that the stay member 80 and the inner portion adjacent to the stay member 80 are disposed. The side wall of the pipe 34 is brought into a non-contact state, and the smooth rotation operation of the stay member 80 can be ensured.

  The fixed side arm 46b of the torsion coil spring 46 extends linearly and engages the lower side of the annular groove 74 formed in the valve shaft 52, and the fixed side arm 46b of the torsion coil spring 46 has its spring force. To prevent displacement upward.

The exhaust system 10 in which the exhaust flow control valve 30 according to the present embodiment is incorporated is basically configured as described above. Next, the function and effect will be described.
FIG. 7 is an explanatory view of the operation of the exhaust flow control valve according to the present embodiment. FIG. 7 (a) shows the valve closed state of the valve body, and FIG. 7 (b) and FIG. 7 (c) The valve state of the valve body is shown.

  When an engine (not shown) is driven (operated), exhaust gas discharged from the engine is introduced into the exhaust system 10. After the exhaust gas flow rate is controlled through the first silencer 12 and the exhaust flow rate control valve 30, the exhaust gas is exhausted by the second silencer 14a, 14b and the third silencer 16a, 16b on the downstream side. The sound is muted and discharged to the outside.

  At this time, for example, when the engine rotation speed including idling operation and start operation is in a low speed region, the combustion pressure of the engine (combustion chamber) is low, and the exhaust pressure of the exhaust gas discharged from the engine also decreases. Therefore, the exhaust pressure of the exhaust gas introduced into the exhaust system 10 is also low.

  Therefore, as shown in FIG. 7A, the exhaust flow control valve 30 is held in the valve closed state in which the valve element 42 abuts against the stopper member 60 by the urging force (spring force) of the torsion coil spring 46. Therefore, the exhaust gas passage area formed by the gap 67 (see FIG. 2B) between the inner wall of the inner pipe 34 and the outer surface of the valve body 42 is the most constricted state (minimum area). As a result, the exhaust flow control valve 30 reduces the exhaust energy of the exhaust gas exhausted from the output side of the first silencer 12 and preliminarily silences the exhaust noise before the second silencers 14a and 14b. And the filling efficiency of the engine is increased.

  In other words, in the exhaust flow control valve 30 according to the present embodiment, even if the valve body 42 is biased to the closing side by the biasing force of the torsion coil spring 46, the exhaust passage of the inner pipe 34 is the valve. The exhaust gas having a reduced flow rate flows through a gap 67 formed between the inner wall of the inner pipe 34 and the outer surface of the valve body 42 without being completely sealed by the body 42.

  On the other hand, when the combustion state of the engine becomes a complete explosion state and the engine rotation speed reaches the high speed region, the combustion pressure of the engine (combustion chamber) increases and the exhaust pressure of the exhaust gas discharged from the engine also increases. Become. Therefore, the exhaust gas dynamic pressure introduced into the exhaust flow control valve 30 from the inlet port 32a in the exhaust system 10 also increases, and the force that presses the valve element 42 against the biasing force of the torsion coil spring 46 increases. As a result, the force that presses the valve body 42 overcomes the urging force of the torsion coil spring 46, whereby the valve body 42 rotates counterclockwise by a predetermined angle with the valve shaft 52 as a rotation fulcrum (FIG. 7 ( b), the valve body 42 is switched from the valve closed state in which the valve body 42 is in contact with the stopper member 60 to the valve open state in which the valve body 42 is tilted by a predetermined angle in a direction away from the stopper member 60.

  That is, when the valve body 42 is pressed by the pressing force of the exhaust gas dynamic pressure introduced from the inlet port 32a of the inner pipe 34, the valve body 42 is in the direction of arrow A (counterclockwise direction) with the valve shaft 52 as a fulcrum. The stay member 80 fixed to the valve shaft 52 integrally rotates in the direction of arrow A (counterclockwise direction) with the valve shaft 52 as a fulcrum. In this case, the sphere 78 pivotally supported by the bent portion 46d of the movable arm 46c of the torsion coil spring 46 rolls along the holding surface 80a of the stay member 80, as shown in FIG. 7B. Move while. The fixed arm 46 b of the torsion coil spring 46 is held in a state of being locked in the annular groove 74 of the valve shaft 52.

  The valve body 42 is switched from the valve closed state to the valve open state, and the exhaust gas passage area of the exhaust gas flowing through the inner pipe 34 gradually increases. As shown in FIG. When is fully opened, the exhaust gas passage area becomes the maximum area. Therefore, the exhaust pressure loss when the engine speed is in the high speed region is reduced by appropriately controlling the exhaust gas flow rate by the exhaust flow rate control valve 30.

  In the present embodiment, an annular groove 74 is provided at a portion exposed along the axial direction of the valve shaft 52 that serves as a pivot point of the valve body 42 and exposed to the outside of the inner tube 34, and the torsion coil spring 46 is fixed. By locking the side arm 46b with the annular groove 74 of the valve shaft 52, for example, a special member for fixing the fixed end of the torsion coil spring 46 provided in the prior art (for example, a plate or a lock) The manufacturing cost can be reduced by reducing the number of parts.

  In other words, if the valve shaft 52 is not provided with a locking portion (fixing portion) for locking (fixing) the fixed side arm 46b which is a fixed end of the torsion coil spring 46, the torsion coil spring provided in the prior art is provided. A special member (for example, a plate or a locking piece) for fixing the fixed end of 46 is required. In this embodiment, the weight of the entire apparatus is reduced by eliminating such a special member. It can be reduced and the assembling work can be simplified.

  Further, in the present embodiment, the annular groove 74 is easily manufactured by forming the annular groove 74 along the outer peripheral surface of the valve shaft 52 as a locking portion for locking the fixed side arm 46 b of the torsion coil spring 46. In addition, since it is only necessary to hook the fixed arm 46b on the annular groove 74 of the valve shaft 52 during the assembly, the assemblability can be improved.

  Further, in the present embodiment, the fixed side arm 46 b of the torsion coil spring 46 that is locked in the annular groove 74 of the valve shaft 52 becomes an obstacle when the valve shaft 52 rotates integrally with the valve body 42. In this way, smooth rotation of the valve shaft 52 can be ensured.

  Furthermore, in this embodiment, the fixed side arm 46 b of the torsion coil spring 46 is restrained by a locking portion provided on the valve shaft 52, and various members are combined with the stay member 80 fixed to the valve shaft 52. Space-saving can be achieved by being arranged close to the vicinity of the valve shaft 52 and being consolidated.

  Furthermore, in this embodiment, the fixed side arm 46 b of the torsion coil spring 46 is locked by the annular groove 74 formed in the valve shaft 52, while the movable side arm 46 c of the torsion coil spring 46 is interposed via the sphere 78. The fixed side arm 46b and the movable side arm 46c are connected to the stay member 80 along the axial direction of the screw coil spring 46 so as to be spaced apart from each other by a predetermined distance, thereby preventing mutual interference and smoothly applying a biasing force. It can be demonstrated.

10 Exhaust system 30 Exhaust flow control valve 34 Inner pipe (valve body)
42 Valve body 46 Torsion coil spring 46b Fixed arm (fixed end)
52 Valve shaft 74 Annular groove (locking part, groove part)

Claims (5)

In an exhaust flow control valve that is provided in an exhaust system that exhausts exhaust gas discharged from an internal combustion engine to the outside and controls the flow rate of exhaust gas that flows through the exhaust passage by opening and closing the valve body,
A valve body;
A torsion coil spring that biases the valve body disposed inside the valve body to a valve closed state;
A valve shaft pivotally supported by the valve body, connected to the valve body and rotated integrally with the valve body;
An urging force transmission mechanism connected to the movable end of the torsion coil spring and transmitting a spring force of the torsion coil spring to the valve body;
With
The valve shaft is provided with a locking portion for locking the fixed end of the torsion coil spring,
The torsion coil spring urges the valve body to a closed state via the urging force transmission mechanism,
The exhaust flow rate control valve, wherein the urging force transmission mechanism and the fixed end are respectively connected to the valve shaft. The exhaust flow control valve according to claim 1,
The exhaust flow control valve according to claim 1, wherein the locking portion includes a groove formed on an outer peripheral surface of the valve shaft. The exhaust flow control valve according to claim 1,
The exhaust flow control valve according to claim 1, wherein the locking portion is provided on a lower side of the valve shaft. The exhaust flow control valve according to any one of claims 1 to 3,
An exhaust flow control valve, wherein a partition wall member is interposed between the urging force transmission mechanism and the fixed end. The exhaust flow control valve according to any one of claims 1 to 4,
The valve body has a recess that is recessed toward the inside of the valve body;
The exhaust flow control valve, wherein the urging force transmission mechanism and the fixed end are connected to the valve shaft at a position corresponding to the recess.

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