JP4972665B2 - Multi-cylinder engine - Google Patents

Description

  The present invention relates to a multi-cylinder engine, and more particularly to a multi-cylinder engine that can improve output performance and exhaust gas performance.

  As a conventional multi-cylinder engine, as in the present invention, an intake distribution passage is provided on the side surface of the cylinder head, with the crankshaft installation direction being the front-rear direction and the width direction of the cylinder head perpendicular to the crankshaft installation direction being the horizontal direction The EGR valve case, the EGR gas introduction passage, and the intake introduction pipe are arranged in order from the front above the intake distribution passage, and the introduction passage gas inlet of the EGR gas introduction passage is connected to the valve case gas outlet of the EGR valve case. The EGR gas introduction passage has an introduction passage gas outlet communicated with the intake inlet pipe on the front side of the peripheral wall of the intake introduction pipe, and flows into the intake air introduced along the axial length direction of the intake introduction pipe from the front side of the peripheral wall of the intake introduction pipe There is one in which gas is mixed and the intake air mixed with the EGR gas is distributed to the intake port of each cylinder in an intake distribution passage (see, for example, Patent Document 1).

  However, in the conventional multi-cylinder engine, the valve mounting frame protrudes from the valve case gas outlet of the EGR valve case into the EGR gas introduction passage, and the EGR gas flows backward from the EGR gas introduction passage to the EGR valve case in the valve mounting frame. There is a problem because a reed valve is installed to prevent this.

JP 2008-75632 A (see FIGS. 1 and 2)

The above prior art has the following problems.
<Problem> Output performance and exhaust gas performance may deteriorate.
Output performance and exhaust gas performance may deteriorate.
The reason is estimated as follows.
A valve mounting frame protrudes from the valve case gas outlet of the EGR valve case into the EGR gas introduction passage, and a reed valve for preventing the backflow of EGR gas from the EGR gas introduction passage to the EGR valve case is attached to the valve mounting frame. Therefore, the distance until the EGR gas that has passed through the reed valve is guided to the intake introduction pipe in the EGR gas introduction passage is relatively short, and the EGR gas that has just passed through the reed valve is not aligned in the direction of the intake introduction pipe. Flow into. For this reason, the penetration force of the EGR gas along the radial direction of the intake pipe is weak, the EGR gas is mixed into the intake air only near the EGR gas inlet, and the EGR gas is not uniformly distributed throughout the intake air and is supplied to each cylinder. The EGR gas concentration in the intake air differs and the output performance and exhaust gas performance deteriorate.

  An object of the present invention is to provide a multi-cylinder engine that can solve the above-described problems, that is, a multi-cylinder engine that can improve output performance and exhaust gas performance.

Invention specific matters of the invention according to claim 1 are as follows.
The installation direction of the crankshaft (1) is the front-rear direction, and the width direction of the cylinder head (2) perpendicular to the installation direction of the crankshaft (1) is the lateral direction.
As illustrated in FIG. 1 (A), an intake distribution passage (3) is provided on the lateral side surface of the cylinder head (2), and an EGR valve case (5) is disposed above the intake distribution passage (3) in order from the front. An EGR gas introduction passage (6) and an intake introduction pipe (7) are arranged, and an introduction passage gas inlet (11) of the EGR gas introduction passage (6) is connected to the valve case gas outlet (10) of the EGR valve case (5). The inlet passage gas outlet (12) of the EGR gas inlet passage (6) communicates with the intake inlet pipe (7) on the front side of the peripheral wall of the inlet inlet pipe (7).
EGR gas (15) flowing from the front side of the peripheral wall of the intake air introduction pipe (7) is mixed into the intake air (14) introduced along the axial length direction of the intake air introduction pipe (7), and this EGR gas (15) is mixed. In the multi-cylinder engine in which the intake air (14) is distributed to the intake ports (16) and (16) of each cylinder in the intake air distribution passage (3),
As illustrated in FIG. 1A, an EGR gas introduction passage is formed at the boundary between the valve case gas outlet (10) of the EGR valve case (5) and the introduction passage gas inlet (11) of the EGR gas introduction passage (6). A reed valve (17) for preventing the backflow of the EGR gas (15) from the (6) to the EGR valve case (5);
As illustrated in FIGS. 2B and 2C, a valve port (19) is provided in the plate material (26), and the base (52) of the plate-like valve body (18) is fixed to the plate material (26). As shown in FIG. 2 (G), the base portion (52) of the valve body (18) and the peripheral portion (28) of the plate member (26) form the valve case gas outlet peripheral portion of the EGR valve case (5). (22) and an inlet passage gas inlet peripheral portion (23) of the EGR gas introduction passage (6), and a base portion (52) of the valve body (18) and a peripheral portion (28) of the plate member (26) Is a multi-cylinder engine characterized by having gaskets (29) and (30).

(Invention according to Claim 1)
<Effect> Output performance and exhaust gas performance can be improved.
Output performance and exhaust gas performance can be improved. The reason is estimated as follows.
As illustrated in FIG. 1A, an EGR gas introduction passage is formed at the boundary between the valve case gas outlet (10) of the EGR valve case (5) and the introduction passage gas inlet (11) of the EGR gas introduction passage (6). Since the reed valve (17) for preventing the backflow of the EGR gas (15) from the (6) to the EGR valve case (5) is arranged, the EGR gas (15) that has passed through the reed valve (17) is introduced into the EGR. The distance until the air is guided to the intake pipe (7) in the passage (6) can be made relatively long, and the EGR gas (15) that has passed through the reed valve (17) passes through the EGR gas introduction passage (6). After the direction is aligned in the passage forming direction, the air flows from the introduction passage gas outlet (12) to the intake introduction pipe (7). Therefore, the penetration force of the EGR gas (15) along the radial direction of the intake air intake pipe (7) is strong, and the EGR gas (15) is mixed into the intake air (14) in a wide range in the radial direction of the intake air intake pipe (7). The EGR gas (15) is uniformly distributed throughout the intake air (14), the concentration of the EGR gas (15) in the intake air (14) supplied to each cylinder is equalized, and the output performance and exhaust gas performance are improved. Can be increased.

<Effect> The reed valve can be arranged in a space-saving manner.
As illustrated in FIGS. 2B and 2C, a valve port (19) is provided in the plate material (26), and the base (52) of the plate-like valve body (18) is fixed to the plate material (26). As shown in FIG. 2 (G), the base portion (52) of the valve body (18) and the peripheral portion (28) of the plate member (26) form the valve case gas outlet peripheral portion of the EGR valve case (5). (22) and an inlet passage gas inlet peripheral portion (23) of the EGR gas introduction passage (6), and a base portion (52) of the valve body (18) and a peripheral portion (28) of the plate member (26) Since the gaskets (29) and (30) are used, the reed valve (17) can be arranged in a space-saving manner.

<Effect> The number of parts of the engine can be reduced.
As illustrated in FIGS. 2B and 2C, the base portion (52) of the valve body (18) and the peripheral portion (28) of the plate member (26) are formed as gaskets (29) and (30). Special parts for gaskets are no longer required, and the number of engine parts can be reduced.

<Effect> The valve body can be easily attached.
As shown in FIG. 2 (D), since the base (52) of the plate-like valve body (18) is fixed to the plate material (26), the valve body (18) is simultaneously attached by attaching the plate material (26). The valve body (18) can be easily attached.

<Effect> The durability of the reed valve can be increased.
As shown in FIG. 2 (G), the peripheral portion (28) of the plate member (26) and the base portion of the valve body (18) form the valve case gas outlet peripheral portion (22) of the EGR valve case (5) and the EGR gas. Since it is sandwiched between the introduction passage gas inlet peripheral portion (23) of the introduction passage (6), the reed valve (due to slight vibration of the base portion (52) of the valve body (18) or excessive opening of the valve body (18)). 17) is suppressed, and the durability of the reed valve (17) can be increased.

(Invention of Claim 2)
In addition to the effect of the invention according to claim 1, the following effect is achieved.
<Effect> Damage to the valve body is suppressed.
As illustrated in FIGS. 9B and 9C, the valve body 18 is provided with an extrusion-like protrusion 58 that protrudes on one surface side and is recessed on the other surface side. Since the body (18) is reinforced, damage to the valve body (18) caused by repeated bending stress on the valve body (18) and collision with the valve seat (32) is suppressed.

(Invention of Claim 3)
In addition to the effect of the invention according to claim 2, the following effect is achieved.
<Effect> It is possible to prevent a problem of seating of the valve body due to the protrusion.
As illustrated in FIGS. 9B and 9C, the protrusion (58) protrudes on the opposite side to the valve port (19) side, and the valve port (19) side is recessed, so that the protrusion (58) The problem of seating of the valve body (18) due to can be prevented.

(Invention of Claim 4)
In addition to the effect of the invention according to claim 2 or claim 3, the following effect is achieved.
<Effect> A decrease in the EGR rate is prevented.
As illustrated in FIG. 9 (A), a plurality of protrusions (58) are arranged side by side along the width direction of the valve body (18) while maintaining a predetermined interval, so that the valve body (18) is twisted. Even if the gas pressure distribution of the EGR gas (15) received by the valve body (18) is not uniform left and right, the valve body (18) opens smoothly while twisting, and the EGR rate decreases. Is prevented.

(Invention according to claim 5)
In addition to the effects of the inventions according to claims 2 to 5, the following effects are achieved.
<Effect> Smooth opening and closing of the valve body is maintained.
As illustrated in FIG. 9 (A), a plurality of protrusions (58) are arranged side by side at predetermined intervals from the intermediate portion of the valve body (18) in the direction of the distal end. ) Is left, and smooth opening and closing of the valve body (18) is maintained.

(Invention of Claim 6)
In addition to the effects of the invention according to any one of claims 1 to 5, the following effects are provided.
<Effect> High sealing performance when the reed valve is closed.
2 (C) and (E), a plurality of valve ports (19) and (19) are arranged side by side on a plate member (26) with valve ports, and the peripheral portions of the valve ports (19) are stepped. Of the valve body side step surfaces (33), (34), the surface (33) closer to the valve body is the valve seat (32), so the rigidity of the valve seat (32) is high, High sealing performance when reed valve is closed.

(Invention according to Claim 7 or Claim 8)
In addition to the effects of the invention according to any one of claims 1 to 6, the following effects are provided.
<Effect> Delay in valve opening is prevented.
2B and 2C, the valve seat (32) is always provided with an opening (35), and the EGR gas (15) ejected from the valve port (19) causes the valve body (18) to Before opening the valve, the EGR gas (15) ejected from the normally open port (35) receives the pressure in the valve opening peripheral portion (36), so that the valve (18) The valve opening delay of the valve element (18) due to sticking to the valve seat (32), stationary inertia of the valve element (18), or the like is prevented.

(Invention according to claim 9)
In addition to the effects of the invention according to any one of claims 1 to 8, the following effects are provided.
<Effect> High function to enhance output performance and exhaust gas performance.
High function to enhance output performance and exhaust gas performance.
The reason is estimated as follows.
As illustrated in FIGS. 1 (A) and 1 (B), the EGR gas introduction passage (6) includes a current plate (39) oriented in the front-rear direction, and the EGR gas (15) extends along the current plate (39). Since it is guided to the intake air intake pipe (7) while being rectified in the straight forward direction, the penetration force of the EGR gas (15) along the radial direction of the intake air intake pipe (7) is increased, and the output performance and exhaust gas are increased. High function to enhance performance.

(Invention according to claim 10)
In addition to the effect of the invention according to claim 9, the following effect is obtained.
<Effect> High function to enhance output performance and exhaust gas performance.
High function to enhance output performance and exhaust gas performance.
The reason is estimated as follows.
As illustrated in FIGS. 1A and 1B, a rectifying plate (39) includes a plurality of downward rectifying plates (41) protruding downward from the upper wall (40) of the EGR gas introduction passage (6). The EGR gas introduction passage (6) is composed of a plurality of upward rectifying plates (43) protruding upward from the lower wall (42) of the EGR gas introduction passage (6), so that the EGR gas (15) is the EGR gas introduction passage (6). Is rectified on both the upper side and the lower side, and the penetration force of the EGR gas (15) along the radial direction of the intake air introduction pipe (7) is strengthened.
Further, as illustrated in FIG. 1 (B), an upper section passage (44) divided by a downward rectifying plate (41) and a lower section passage (45) divided by an upward rectifying plate (43). Since each section passage (46) communicates with each other via the lower opening (47) of the upper section passage (44) and the upper opening (48) of the lower section passage (45), each section passage ( The amount of EGR gas passing through 46) is equalized.
For these reasons, the EGR gas (15) is uniformly dispersed throughout the intake air (14) passing through the intake air intake pipe (7), and the EGR gas concentration in the intake air (14) supplied to each cylinder is equalized. , Output performance and exhaust gas performance can be enhanced.

(Invention of Claim 11)
In addition to the effect of the invention according to claim 10, the following effect is achieved.
<Effect> High function to enhance output performance and exhaust gas performance.
High function to enhance output performance and exhaust gas performance.
The reason is estimated as follows.
As illustrated in FIG. 1B, the downward rectifying plate (41) protrudes toward the lower section passage (45), and the upward rectifying plate (43) protrudes toward the upper section passage (44). Therefore, the gap between the projecting ends of the downward rectifying plate (41) and the upward rectifying plate (43) is larger than when the downward rectifying plate (41) and the upward rectifying plate (43) are projected in abutment with each other. Through this gap, the amount of EGR gas passing through each section passage (46) is equalized, and the EGR gas (15) is uniformly distributed throughout the intake air (14) passing through the intake air intake pipe (7). Dispersed and the EGR gas concentration in the intake air (14) supplied to each cylinder is equalized, and the output performance and exhaust gas performance can be improved.

(Invention of Claim 12)
In addition to the effect of the invention according to claim 10 or claim 11, the following effect is achieved.
<Effect> The durability of the reed valve can be increased.
As illustrated in FIG. 2 (G), an extension (49) is provided on the front upper side of the downward rectifying plate (41), and this extension (49) is provided with a valve opening stopper (50) of the valve body (18) and The valve body restraining portion (51) is arranged above the valve opening stopper (50), and the valve body gas outlet (51) between the valve body restraining portion (51) and the EGR valve case (5) ( 10) The base portion (52) of the valve body (18) is sandwiched by the upper opening edge portion (56), and the valve body portion (53) below the base portion (52) of the valve body (18) is Since the valve is bent and opened, the reed valve (17) is prevented from being damaged by slight vibration of the base (52) of the valve body (18) and excessive opening of the valve body (18). The durability of 17) can be increased.

(Invention of Claim 13)
In addition to the effect of the invention according to claim 12, the following effect is achieved.
<Effect> A decrease in the EGR rate is prevented.
A decrease in the EGR rate is prevented.
The reason is estimated as follows.
As illustrated in FIG. 2 (H), both lateral edges (54) and (54) of the extension (49) are disposed more inward than the lateral edges (55) and (55) of the valve element (18). Therefore, the valve body (18) is moved until the both lateral edges (55) (55) of the valve body (18) are located rearward of the valve opening stopper (50) and the valve body restraining portion (51). Even if there is room for twisting and the gas pressure distribution of the EGR gas (15) received by the valve body (18) is not uniform left and right, the valve body (18) opens smoothly while twisting, and the EGR rate decreases. Is prevented.

(Invention according to Claim 14)
In addition to the effect of the invention according to claim 12 or claim 13, the following effect is achieved.
<Effect> It is possible to prevent the solid content from being caught in the reed valve.
As illustrated in FIG. 2G, a solid content falling space (57) is formed below the lower valve body portion (53) in the introduction passage gas inlet (11) of the EGR gas introduction passage (6). Since the solid content such as carbon that has reached the lower valve body portion (53) falls downward through the solid content drop space (57), the solid content in the reed valve (17) is reduced. Biting can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a multi-cylinder engine according to a first embodiment of the present invention, in which FIG. 1 (A) is a partially longitudinal side view of an intake distribution passage and its periphery, and FIG. 1 (B) is B in FIG. FIG. FIG. 2A is a front view of an intake distribution passage wall, FIG. 2B is a front view of a plate member with a valve body, and FIG. 2C is a diagram illustrating a multi-cylinder engine according to a first embodiment of the present invention. ) Is a front view of a plate with a valve opening, FIG. 2 (D) is a longitudinal side view of a stacked gasket, FIG. 2 (E) is a cross-sectional view taken along line EE of FIG. 2 (C), and FIG. FIG. 2 (G) is a vertical side view of the vicinity of the reed valve, and FIG. 2 (H) is an introduction passage gas inlet and valve of the EGR gas introduction passage. FIG. 2 (I) is a front view of a normally opened opening and a notch superimposed on one end side in the width direction of the valve body. FIGS. 3A and 3B are diagrams illustrating an intake distribution passage wall used in the multi-cylinder engine according to the first embodiment of the present invention, in which FIG. 3A is a side view, FIG. 3B is a plan view, and FIG. 3D is a rear view, and FIG. 3E is a cross-sectional view taken along the line EE of FIG. 3A. FIG. 4 is a side view of the intake distribution passage wall of FIG. 3 as viewed from the cylinder head side. It is a figure explaining the multicylinder engine which concerns on embodiment of this invention, and is a top view of a cylinder head and its peripheral components. 1 is a side view of a multi-cylinder engine according to a first embodiment of the present invention. 1 is a plan view of a multi-cylinder engine according to a first embodiment of the present invention. 1 is a front view of a multi-cylinder engine according to a first embodiment of the present invention. FIGS. 9A and 9B are views for explaining a reed valve used in the multi-cylinder engine according to the first embodiment of the present invention, FIG. 9A is a front view of a plate member with a valve body, and FIG. 9B is B- in FIG. B line sectional drawing and Drawing 9 (C) are CC line sectional views of Drawing 9 (A). FIG. 10A is a view for explaining a reed valve used in a multi-cylinder engine according to a second embodiment of the present invention, and FIG. B) is a front view of a normally opened opening and a notch superimposed on one end side in the width direction of the valve body.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 to FIG. 9 are diagrams for explaining a multi-cylinder engine according to a first embodiment of the present invention, and FIG. 10 is a diagram for explaining a multi-cylinder engine according to a second embodiment. A diesel engine will be described.

The outline of the first embodiment of the present invention is as follows.
As shown in FIG. 6, the cylinder head (2) is assembled to the upper part of the cylinder block (61), the oil pan (62) is assembled to the lower part of the cylinder block (61), and the front of the cylinder block (61) is assembled. A water pump (63) and an oil pump (64) are assembled, and a flywheel housing (65) is assembled at the rear of the cylinder block (61).
A crankshaft (1) is installed in a crankcase (66) formed in the lower part of the cylinder block (61).

The installation direction of the crankshaft (1) is the front-rear direction, and the width direction of the cylinder head (2) perpendicular to the installation direction of the crankshaft (1) is the lateral direction.
As shown in FIG. 5, an exhaust merging passage (67) is provided on one of the lateral sides of the cylinder head (2), and an intake air distribution passage (3) is provided on the other side. The exhaust merge passage (67) is provided in the exhaust merge passage wall (68), and the intake distribution passage (3) is provided in the intake distribution passage wall (69). As shown in FIG. 1 (A), the intake distribution passage wall (69) is used to distribute intake air to the intake port (16) of each cylinder, and is called a so-called intake manifold. As shown in FIGS. 4 (A) to (E) and FIG. 4, this embodiment has a box shape without branch pipes, and is therefore referred to as an intake distribution passage wall (69) and an intake distribution passage (3). ing. As shown in FIG. 5, the exhaust merging passage (67) is for merging exhaust from the exhaust port (70) of each cylinder, and the exhaust merging passage wall (68) is a so-called exhaust manifold. However, they are referred to as an exhaust merging passage wall (68) and an exhaust merging passage (67) in order to match the part name of the intake distribution passage wall (69).

The configuration of the EGR device is as follows.
As shown in FIG. 1 (A), an EGR valve (71) is accommodated in an EGR valve case (5), the EGR valve (71) is opened, and an EGR gas is supplied from the exhaust side to the intake distribution passage (3). (15) is refluxed. The EGR valve (71) is biased in the valve closing direction by the spring force of the valve spring (72), and the EGR valve (71) is linked to the pneumatic valve actuator (73). The air pressure chamber (74) communicates with the intake air distribution passage (3), and the intake air distribution passage (3) is supercharged by a supercharger (75) driven by exhaust energy. As shown in FIGS. 6 and 7, the intake air distribution passage (3) is supercharged via an intake air supply pipe (95).

As shown in FIG. 5, the intake pressure chamber (74) of the valve actuator (73) is communicated with the intake distribution passage (3) via the intake pressure introduction pipe (76), and the intake pressure introduction pipe (76) is sensed. At the time of cold start when the engine temperature is less than a predetermined value, the intake pressure cutoff valve (77) is closed and the boost pressure in the intake distribution passage (3) is arranged. Regardless of this, the EGR valve (71) is maintained in the fully closed state, and the intake pressure shut-off valve (77) is opened at the time of warm start when the engine temperature is equal to or higher than a predetermined value or during normal operation, and the intake distribution passage (3 The opening degree of the EGR valve (71) is adjusted according to the supercharging pressure in the bracket.
The intake pressure cutoff valve (77) is attached to the EGR valve case (5), and the heat input portion (78) of the intake pressure cutoff valve (77) faces the valve cooling water passage (79) in the EGR valve case (5). It is out. The intake pressure shut-off valve (77) includes temperature-sensitive deformation means such as bimetal inside, and opens and closes the valve using deformation due to the temperature as a driving force. The valve cooling water channel (79) shown in FIG. 5 is formed in a U shape in plan view.

The arrangement of each part of the EGR device is as follows.
As shown in FIG. 1 (A), an intake distribution passage (3) is provided on the lateral surface of the cylinder head (2), and an EGR cooler (4) and an EGR valve are sequentially provided above the intake distribution passage (3) from the front. A case (5), an EGR gas introduction passage (6), and an intake introduction pipe (7) are arranged, and a valve case gas inlet (9) of the EGR valve case (5) is connected to a cooler gas outlet (8) of the EGR cooler (4). Are connected to the gas passage (10) of the EGR valve case (5) and the gas passage (11) of the EGR gas introduction passage (6) is connected to the gas passage (6) of the EGR gas introduction passage (6). (12) communicates with the intake inlet pipe (7) on the front side of the peripheral wall of the intake inlet pipe (7).
The intake intake pipe (7) is vertically raised at the rear end of the intake distribution passage wall (69). The longitudinal direction (front-rear direction) of the intake distribution passage (3) is a horizontal direction, and the EGR gas introduction passage (6) is inclined downward toward the intake introduction pipe (7) at a depression angle of 10 ° with reference to the horizontal direction. is doing. This depression angle is preferably less than 30 ° and more preferably less than 15 ° from the viewpoint of imparting the radial penetration force of the intake pipe (7) to the EGR gas (15).
As shown in FIG. 1A, EGR gas (15) flowing from the front side of the peripheral wall of the intake air introduction pipe (7) is mixed into the intake air (14) introduced along the axial length direction of the intake air introduction pipe (7). The intake air (14) mixed with the EGR gas (15) is distributed to the intake ports (16) and (16) of the respective cylinders through the intake air distribution passage (3).

  As shown in FIG. 1A, at the boundary between the valve case gas outlet (10) of the EGR valve case (5) and the introduction passage gas inlet (11) of the EGR gas introduction passage (6), the EGR gas introduction passage ( A reed valve (17) for preventing the backflow of the EGR gas (15) from 6) to the EGR valve case (5) is disposed.

The configuration of the reed valve is as follows.
As shown in FIGS. 2B and 2C, a valve port (19) is provided in the plate material (26), and the base (52) of the plate-shaped valve body (18) is fixed to the plate material (26). As illustrated in FIG. 2 (G), the base portion (52) of the valve body (18) and the peripheral portion (28) of the plate member (26) form a valve case gas outlet peripheral portion of the EGR valve case (5) ( 22) and an inlet passage gas inlet peripheral portion (23) of the EGR gas introduction passage (6), and a base portion (52) of the valve body (18) and a peripheral portion (28) of the plate member (26). Gaskets 29 and 30 are provided.
A sheet metal such as a steel plate is used for the plate material (26) and the valve body (18). The base (52) of the valve body (18) is fixed to the plate (26) by spot welding.

As illustrated in FIG. 2 (C), the plate member (26) with a valve port is provided with a valve port (19) in the plate member (26), and the plate member portion at the peripheral portion of the valve port (19) is a valve seat. (32).
As shown in FIGS. 2 (C) and 2 (E), a plurality of valve ports (19) and (19) are arranged side by side on a plate (26) with valve ports, and the peripheral portions of the valve ports (19) are stepped. Of the formed valve body side step surfaces (33) and (34), the surface (33) closer to the valve body is the valve seat (32).

As shown in FIG. 2 (C), the valve seat (32) is always provided with an opening (35) on the front end side and the width direction both ends, and the EGR is ejected from the valve port (19). Before the valve body (18) is opened by the gas (15), the valve body peripheral part (36) is subjected to pressure in the valve opening direction by the EGR gas (15) ejected from the normally open port (35). It has become.
As shown in FIG. 2 (F) (I), the opening (35) is always formed in a circular shape on the front end side and the width direction both ends of the valve body (18), and when the valve body (18) is fully closed, A part of the normally open port (35) is covered with the peripheral edge portion (36) of the valve body so that the EGR gas (15) ejected from the normally open port (35) blows against the peripheral edge portion (36) of the valve body. .

As shown in FIGS. 9B and 9C, the valve body 18 of the reed valve 17 is provided with an extruded protrusion 58 that protrudes on one side and is recessed on the other side. The valve body (18) is reinforced by (58).
The protrusion (58) protrudes on the opposite side to the valve port (19) side and is recessed on the valve port (19) side.
A plurality of protrusions (58) are arranged side by side along the width direction of the valve body (18) while maintaining a predetermined interval.
A plurality of protrusions (58) are arranged side by side at predetermined intervals from the intermediate part of the valve body (18) in the direction of the tip.
That is, four rows of protrusions (58) arranged along the width direction of the valve body (18), and three rows of protrusions (58) from the middle portion of the valve body (18) along the tip direction. Yes.
The two protrusions (58) at the center in the width direction of the valve body (18) are formed long in the width direction of the valve body (18), and the protrusions (58) on both sides are formed of the valve body (18). It is long in the longitudinal direction.

As shown in FIGS. 1 (A) and 1 (B), the EGR gas introduction passage (6) includes a rectifying plate (39) oriented in the front-rear direction, and the EGR gas (15) is moved along the rectifying plate (39). While being straightened in the straight direction, it is guided to the intake air introduction pipe (7).
As shown in FIGS. 1A and 1B, a rectifying plate (39) includes a plurality of downward rectifying plates (41) protruding downward from the upper wall (40) of the EGR gas introduction passage (6); A plurality of upward rectifying plates (43) projecting upward from the lower wall (42) of the EGR gas introduction passage (6).
As shown in FIG. 1 (B), each divided passage comprising an upper divided passage (44) divided by a downward rectifying plate (41) and a lower divided passage (45) divided by an upward rectifying plate (43). (46) communicate with each other via the lower opening (47) of the upper section passage (44) and the upper opening (48) of the lower section passage (45).
As shown in FIG. 1 (B), the downward rectifying plate (41) protrudes toward the lower section passage (45), and the upward rectifying plate (43) protrudes toward the upper section passage (44). .

As shown in FIG. 2 (G), an extension part (49) is provided on the upper front side of the downward rectifying plate (41), and this extension part (49) serves as a valve opening stopper (50) and a valve of the valve body (18). The valve body restraining part (51) is disposed above the valve opening stopper (50), and the valve body gas outlet (10) of the valve body restraining part (51) and the EGR valve case (5) is provided. ) Is sandwiched by the upper opening edge portion (56), and the valve body portion (53) below the base portion (52) of the valve body (18) is bent. The valve is opened.
As shown in FIG. 2 (H), both lateral edges (54) and (54) of the extension (49) are disposed inwardly of the lateral edges (55) and (55) of the valve element (18). ing.
As shown in FIG. 2 (G), a solid content falling space (57) is formed below the lower valve body portion (53) in the introduction passage gas inlet (11) of the EGR gas introduction passage (6). ing.
The intake distribution passage wall (69), the intake introduction pipe (7), the passage wall of the EGR gas introduction passage (6), the downward rectifying plate (41), its extension (49), and the upward rectifying plate (43) are a series of This is a cast integrated product.

The configuration of the EGR gas cooling device is as follows.
As shown in FIG. 5, the cylinder head (2) is provided with an in-head EGR passage (80) that passes through the water-cooling jacket. A connecting pipe (94) is attached to the side surface of the cylinder head (2) in front of the intake distribution passage (3), and the EGR cooler (4) is connected to the EGR passage (80) in the head via the connecting pipe (94). The EGR gas (15) is introduced into the tank.
As shown in FIG. 5, a cooler jacket (81) is formed in the EGR cooler (4), a valve cooling water passage (79) is formed in the EGR valve case (5), and the cooler jacket (81) and the valve cooling are formed. The water channel (79) is connected in series via the cooling water relay pipe (83). As shown in FIG. 6, the cooler jacket inlet (84) of the cooler jacket (81) communicates with the cylinder jacket outlet (86) via the cooling water inlet pipe (85). The cooler jacket outlet (87) of the cooler jacket (81) communicates with the water channel inlet (88) of the valve cooling water channel (82) via the cooling water relay pipe (83). The water passage outlet (89) of the valve cooling water passage (82) communicates with the passage inlet (91) of the cooling water suction passage (not shown) via the cooling water outlet pipe (90). A passage outlet (not shown) of the cooling water suction passage communicates with a suction port (not shown) of the water pump (63). The cooling water in the cylinder jacket is cooled by the suction force of the water pump (63), the cylinder jacket outlet (86), the cooler jacket (81), the valve cooling water passage (82), the cooling water outlet pipe (90), and the cooling water suction passage. Are sequentially sucked into the water pump (63), merged with the other cooling water, pumped to the radiator (not shown), and returned to the cylinder jacket again.

  As shown in FIGS. 1 (A) and 5, an out-head EGR passage (92) passing outside the cylinder head (2) is led out from the exhaust merging passage (67), and downstream of the out-head EGR passage (92). The EGR cooler (4) is disposed in the EGR cooler (4) so that EGR gas is introduced into the EGR cooler (4) from both the in-head EGR passage (80) and the outside-head EGR passage (92).

  As shown in FIGS. 6 to 8, an EGR passage (92) outside the head is disposed behind the engine cooling fan (93), and the engine cooling caused by the engine cooling fan (93) is caused in the EGR passage outside the head (92). The wind blows. As shown in FIG. 8, when viewed in a direction parallel to the installation direction of the crankshaft (1), the EGR passage (92) outside the head is slightly shifted from the position overlapping the engine cooling fan (93). Since the engine cooling air blowing area is larger than the locus of the outer periphery of the engine cooling fan (93), the engine cooling air blows against the head outside EGR passage (92).

The second embodiment shown in FIG. 10 is different from the first embodiment in the following points.
In the second embodiment, as shown in FIGS. 10 (A) and 10 (B), the valve body peripheral portion (36) has a normally open opening (35) on the front end side and the width direction both end sides of the valve body (18). An arc-shaped notch (37) that is concentric and smaller in diameter than the normally-opening opening (35) is provided, and the EGR gas (15) ejected from the normally-opening opening (35) is the peripheral edge of the arc-shaped notch (37). (38).
In this case, out of the EGR gas (15) ejected from the normally open port (35), the gas ejected from the center of the normally opened port (35) having the fastest flow velocity passes through the notch (37), and the flow velocity is Since the jet gas from the peripheral edge of the slow continuous opening (35) blows to the peripheral edge (38) of the arc-shaped cutout (37), the rebound of the jet gas to the constant open opening (35) is gentle, Occurrence of turbulent flow of the EGR gas (15) in the vicinity of the valve body peripheral portion (36) is suppressed, vibration of the valve body (18) due to turbulence hardly occurs, valve opening delay due to vibration is prevented, and the valve body ( 18) The valve opening delay prevention function is high.
Other configurations and functions are the same as those of the first embodiment.

(2) Cylinder head
(3) Intake distribution passage
(5) EGR valve case
(6) EGR gas introduction passage
(7) Intake inlet pipe
(10) Valve case gas outlet
(11) Inlet passage gas inlet
(12) Introduction passage gas outlet
(13) EGR gas inlet
(14) Inhalation
(15) EGR gas
(16) Intake port
(17) Reed valve
(18) Disc
(19) Valve mouth
(22) Valve case gas outlet periphery
(23) Inlet passage gas inlet periphery
(24) Gasket
(26) Plate material with valve opening
(27) Perimeter
(28) Perimeter
(29) Gasket
(30) Gasket
(31) Slit
(32) Valve seat
(33) Valve element side step surface
(34) Step surface on the valve disc side
(35) Regular opening
(36) Valve body periphery
(39) Current plate
(40) Upper wall
(41) Downward current plate
(42) Lower wall
(43) Upward current plate
(44) Upper section passage
(45) Lower section passage
(46) Each section passage
(47) Lower opening
(48) Upper opening
(49) Extension
(50) Valve opening stopper
(51) Valve body restraint part
(52) Base
(53) Lower valve body
(54) Both lateral edges of the extension
(55) Both lateral edges of the disc
(56) Upper opening edge
(57) Solids falling space
(58) Protrusion

Claims (14)

The installation direction of the crankshaft (1) is the front-rear direction, and the width direction of the cylinder head (2) perpendicular to the installation direction of the crankshaft (1) is the lateral direction.
An intake distribution passage (3) is provided on the lateral surface of the cylinder head (2), and an EGR valve case (5), an EGR gas introduction passage (6), and an intake introduction pipe are sequentially arranged above the intake distribution passage (3) from the front. (7) is disposed, the introduction gas inlet (11) of the EGR gas introduction passage (6) is communicated with the valve case gas outlet (10) of the EGR valve case (5), and the EGR gas introduction passage (6) The introduction passage gas outlet (12) communicates with the intake introduction pipe (7) on the front side of the peripheral wall of the intake introduction pipe (7).
EGR gas (15) flowing from the front side of the peripheral wall of the intake air introduction pipe (7) is mixed into the intake air (14) introduced along the axial length direction of the intake air introduction pipe (7), and this EGR gas (15) is mixed. In the multi-cylinder engine in which the intake air (14) is distributed to the intake ports (16) and (16) of each cylinder in the intake air distribution passage (3),
From the EGR gas introduction passage (6) to the EGR valve case (5) at the boundary between the valve case gas outlet (10) of the EGR valve case (5) and the introduction passage gas inlet (11) of the EGR gas introduction passage (6) A reed valve (17) for preventing the backflow of the EGR gas (15)
A valve port (19) is provided in the plate material (26), and a base portion (52) of the plate-like valve body (18) is fixed to the plate material (26), and the base portion (52) of the valve body (18) and the plate material The peripheral portion (28) of (26) is sandwiched between the valve case gas outlet peripheral portion (22) of the EGR valve case (5) and the introduction passage gas inlet peripheral portion (23) of the EGR gas introduction passage (6). The multi-cylinder engine is characterized in that the base portion (52) of the valve body (18) and the peripheral portion (28) of the plate member (26) are formed as gaskets (29) and (30). The multi-cylinder engine according to claim 1,
The valve body (18) is provided with an extruded protrusion (58) projecting on one surface side and recessed on the other surface side, and the valve body (18) is reinforced by the protrusion (58). Cylinder engine. The multi-cylinder engine according to claim 2,
The multi-cylinder engine is characterized in that the protrusion (58) protrudes on the side opposite to the valve port (19) side and the valve port (19) side is recessed. The multi-cylinder engine according to claim 2 or 3,
A multi-cylinder engine characterized in that a plurality of protrusions (58) are arranged side by side at a predetermined interval along the width direction of the valve body (18). The multi-cylinder engine according to claim 2, wherein:
A multi-cylinder engine characterized in that a plurality of protrusions (58) are arranged side by side at a predetermined interval from the intermediate part of the valve body (18) in the direction of the tip. The multi-cylinder engine according to any one of claims 1 to 5,
A plurality of valve ports (19) and (19) are arranged side by side on a plate member (26) with a valve port, and the peripheral portion of each valve port (19) is formed in a step shape, and the valve element side step surface (33) (34) ), The surface (33) closer to the valve body is a valve seat (32). The multi-cylinder engine according to any one of claims 1 to 6,
The valve seat (32) is provided with a normally open port (35), and the EGR gas (15) ejected from the valve port (19) is opened from the normally open port (35) before the valve element (18) is opened. A multi-cylinder engine characterized in that the valve body peripheral portion (36) is subjected to pressure in the valve opening direction by the ejected EGR gas (15). The multi-cylinder engine according to claim 7,
When the valve body (18) is fully closed, a part of the normally open port (35) is covered with the valve body peripheral portion (36), and the EGR gas (15) ejected from the normally open port (35) is the valve body peripheral portion. (36) A multi-cylinder engine characterized by being sprayed. The multi-cylinder engine according to any one of claims 1 to 8,
The EGR gas introduction passage (6) includes a rectifying plate (39) oriented in the front-rear direction, and the EGR gas (15) is rectified in the straight line direction along the rectifying plate (39) while the intake introduction pipe (7) A multi-cylinder engine characterized by being guided by the engine. The multi-cylinder engine according to claim 9,
The rectifying plate (39) includes a plurality of downward rectifying plates (41) protruding downward from the upper wall (40) of the EGR gas introduction passage (6), and the lower wall (42) of the EGR gas introduction passage (6). And a plurality of upward rectifying plates (43) protruding upward from
Each section passage (46) comprising an upper section passage (44) sectioned by the downward rectifying plate (41) and a lower section passage (45) sectioned by the upward rectifying plate (43) is divided into an upper section passage (44). ) And a lower section passage (45) through an upper opening (48). The multi-cylinder engine according to claim 10,
A multi-cylinder engine characterized in that a downward rectifying plate (41) protrudes toward the lower section passage (45) and an upward rectifying plate (43) protrudes toward the upper section passage (44). The multi-cylinder engine according to claim 10 or 11,
An extension part (49) is provided on the front upper side of the downward rectifying plate (41), and this extension part (49) is used as a valve opening stopper (50) and a valve body restraining part (51) of the valve body (18). The body restraining part (51) is arranged above the valve opening stopper (50), and is formed by the upper opening edge part (56) of the valve body restraining part (51) and the valve case gas outlet (10) of the EGR valve case (5). , The base (52) of the valve body (18) is sandwiched,
A multi-cylinder engine characterized in that a valve body portion (53) below the base (52) of the valve body (18) is bent and opened. The multi-cylinder engine according to claim 12,
Multi-cylinder characterized in that both lateral edges (54) and (54) of the extension portion (49) are arranged inwardly than both lateral edges (55) and (55) of the valve body (18). engine. The multi-cylinder engine according to claim 12 or 13,
A multi-cylinder characterized in that a solid content drop space (57) is formed below the lower valve body portion (53) in the introduction passage gas inlet (11) of the EGR gas introduction passage (6). engine.

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