JP4646714B2 - Engine intake system - Google Patents

Description

  The present invention relates to improvement of an intake device for an engine, and more particularly to measures for introducing exhaust gas, blow-by gas, purge gas and the like into a surge tank.

Patent Document 1 discloses intake air introduced into a surge tank from an intake supply source through an intake introduction hole, exhaust gas discharged from the gas introduction port into the surge tank through a gas introduction passage and a gas discharge port, and blow-by. Intake device for an engine that mixes incomplete combustion gas containing at least one impurity of gas and purge gas, and supplies it again to the combustion chamber of the engine for recombustion to clean exhaust gas and the like Is disclosed.
JP 2001-140713 A (2nd page, FIG. 6)

  However, according to Patent Document 1, the gas discharge port for discharging gas into the surge tank is positioned above the gas introduction port of the gas introduction passage, and the gas introduction passage is inclined upward toward the gas discharge port. Therefore, when the engine is stopped, the gas introduced into the gas introduction passage from the gas introduction port stays in the gas introduction passage, and when the outside air temperature becomes low as in winter, the gas in the gas introduction passage stays in the gas introduction passage. Moisture freezes, the passage is blocked, and exhaust gas or the like cannot be cleaned. Also, since there is not enough space in the engine room, it may be difficult to assemble a hose that supplies gas depending on the arrangement of the gas inlet.

  The present invention has been made in view of such a point, and the object of the present invention is to prevent the gas from staying in the gas introduction passage and the moisture in the gas from freezing in the gas introduction passage. is there. In addition, the assembly of the gas supply hose is facilitated to improve workability.

  In order to achieve the above object, the present invention is characterized in that the attitude of the gas introduction passage communicating with the surge tank has been devised.

  Specifically, the present invention is formed by joining both divided surfaces of an upper first half having a first divided surface and a lower second half having a second divided surface, and the second half. A plurality of protrusions projecting on the front wall of the surge tank, which is composed of a surge tank having an intake introduction hole formed in the rear wall of the body, and a front wall of the first half and a front wall of the second half The intake air introduced into the surge tank through the intake air introduction hole is mixed with at least one of exhaust gas, blow-by gas, and purge gas, and supplied to the engine via the respective branch tubes. The following solutions were taken for the engine intake system.

That is, according to the first aspect of the present invention, the first half body and the second half body are opened between the rear wall side dividing surfaces in the surge tank at a position above the intake air introduction hole. A gas introduction passage having a gas discharge port at one end for discharging gas into the surge tank is formed, and a gas introduction port for introducing the gas into the gas introduction passage is formed at the other end of the gas introduction passage from the gas discharge port. The gas introduction passage is formed so as to be in an upper position, and the gas introduction passage is inclined downward from the gas introduction port to the gas discharge port as a whole, and further, the dividing surface on the rear wall side in the first half body Is formed with a first half-side bulging portion in which a part of the dividing surface partially bulges upward, and the dividing surface on the rear wall side in the second half is on the first half-side A second half-side bulging portion bulging upward corresponding to the bulging portion is formed, Between detecting portion at least part of the gas inlet passage is formed, the gas inlet is characterized by being formed in the bulged portion.

  According to the first aspect of the present invention, the gas introduction port is formed so as to be positioned above the gas discharge port, and the gas introduction passage is entirely inclined downward from the gas introduction port toward the gas discharge port. Therefore, the gas can be discharged smoothly into the surge tank, the gas does not stay in the gas introduction passage, and the moisture in the gas freezes in the gas introduction passage even when the outside air temperature is low, such as in winter. Can be prevented. Further, since the gas is discharged from the position above the intake air introduction hole, the mixing of the intake air and the gas is improved and supplied to each cylinder of the engine, and the combustion balance is kept uniform.

Further, a part of the gas introduction passage is formed between the bulging portions formed on the rear wall side dividing surface in the first half and the second half, and the gas introduction port is formed on the bulging portion side. Therefore, even if fixtures are arranged around the dividing plane, the gas inlet is above the dividing plane, so it is easy to attach the gas supply hose to the gas inlet and the workability is improved. Is not constrained. In addition, since at least a part of the gas introduction passage is formed between the bulging portions, even if the dividing surface of the portion corresponding to the bulging portion is inclined upward toward the gas discharge port, the gas introduction passage can Can be inclined downwards toward the outlet as a whole, gas is smoothly discharged to the surge tank without staying in the gas introduction passage, and moisture in the gas freezes in the gas introduction passage in winter Can be prevented .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

( Reference Example 1)
Figures 1-6 show the intake device 1 for an engine according to Embodiment 1 of the present invention. The intake device 1 includes both an upper first half 3 having a first dividing surface 2 and opened downward, and a lower second half 5 having a second dividing surface 4 and opened upward. A split-type surge tank 7 formed by joining the split surfaces 2 and 4 is provided, and the first half 3 is composed of a ceiling wall 3a, a front wall 3b, a rear wall 3c, and both side walls 3d, and the second half The body 5 includes a bottom wall 5a, a front wall 5b, a rear wall 5c, and both side walls 5d. In addition, an intake introduction hole 9 is formed substantially at the center of the rear wall 5c of the second half body 5, and a mounting portion 11 to which a throttle valve (not shown) is attached to the outer periphery of the intake introduction hole 9 on the outer surface of the rear wall 5c. Is formed bulging. Then, intake air is introduced into the surge tank 7 from an unillustrated intake supply source through the throttle valve and the intake introduction hole 9.

  The front wall 7a of the surge tank 7 constituted by the front wall 3b of the first half 3 and the front wall 5b of the second half 5 has intake air introduced into the surge tank 7 and exhaust gas. , Three branch pipes 13 that are mixed with at least one of the blow-by gas and the purge gas and are supplied to the engine are projected, and these branch pipes 13 are connected to the half branch pipe portion 13a on the first half 3 side. The second half body 5 is configured in combination with the half-branch pipe portion 13b. The ends of the branch pipes 13 are connected to a mounting flange 15, and a mounting hole 17 is formed in the mounting flange 15. A bolt (not shown) is inserted into the mounting hole 17 to attach the mounting flange 15. It is designed to be fixed to the engine.

  In the first dividing surface 2 and the second dividing surface 4, the dividing surface portions 2a, 4a on the front walls 3b, 5b side and the dividing surface portions 2b, 4b on the rear walls 3c, 5c side are configured in a horizontal plane. On the other hand, the split surface portions 2c and 4c on the side walls 3d and 5d are formed of inclined surfaces that are inclined upward toward the rear walls 3c and 5c.

  Further, flanges 23 and 25 are formed on the first and second divided surfaces 2 and 4 over the entire circumference, and the mating surfaces of the flanges 23 and 25 also constitute a part of the divided surface. A gas introduction passage 27 is formed between the divided surface portions 2b and 4b on the side of the rear walls 3c and 5c (between the mating surfaces of the flanges 23 and 25), and one end of the gas introduction passage 27 is located above the intake introduction hole 9. A gas discharge port 29 that opens into the surge tank 7 at a position and discharges the gas into the surge tank 7 is formed, and is inclined forward and downward toward the surge tank 7. At the other end of the gas introduction passage 27, a gas introduction port 28 for introducing the gas into the gas introduction passage 27 is formed at a position above the gas discharge port 29.

  Specifically, the gas introduction passage 27 includes a groove 27a formed on the lower surface (division surface portion 2b) of the flange 23 on the first half 3 side and a flange 25 (division surface portion 4b) on the second half 5 side. The groove 27b is formed in combination. The groove 27 a on the first half 3 side becomes shallower toward the gas discharge port 29, whereas the groove 27 b on the second half 3 side becomes deeper toward the gas discharge port 29. ing. As a result, the entire gas introduction passage 27 is inclined downward from the gas introduction port 28 toward the gas discharge port 29. A gas introduction pipe 31 is formed on the flange 23 of the rear wall 3 c in the first half 3 so as to communicate with the gas introduction port 28 of the gas introduction passage 27. Gas such as engine exhaust gas is discharged from the gas discharge port 29 into the surge tank 7 through the gas introduction pipe 31, the gas introduction port 28, and the gas introduction passage 27.

As described above, in Reference Example 1, the gas inlet 28 is formed so as to be positioned above the gas outlet 29, and the entire gas inlet passage 27 is inclined downward from the gas inlet 28 toward the gas outlet 29. Therefore, the gas can be smoothly discharged into the surge tank 7 so as not to stay in the gas introduction passage 27, and the moisture in the gas introduction passage 27 can be retained even when the outside air temperature is low as in the winter. Can be prevented from freezing. Further, since the gas is discharged from the position above the intake air introduction hole 9, the mixture of the intake air and the gas is improved and supplied to each cylinder of the engine, and the combustion balance is kept uniform. Furthermore, since the gas discharge port 29 is inclined forward and downward toward the inside of the surge tank 7, the gas discharged from the gas discharge port 29 can be guided toward the intake air introduced from the intake air introduction hole 9, Mixing of gas and intake air can be performed more efficiently.

In Reference Example 1, the entire gas introduction passage 27 is inclined downward toward the gas discharge port 29. However, if the gas does not stay in the gas introduction passage 27, a horizontal passage portion is partially provided. It may be provided. The same applies to Embodiments 2 and 3 described below.

(Working-shaped state)
7 to 10 show an intake device 1 of the engine according to the embodiment forms state of the present invention. In this embodiment shaped condition, the flange 23 (split surface 2c, 2b) of the toward the rear wall 3c of the side wall 3d of one of the first half 3 (right in front view) on the top surface is divided surface 2c, part of 2b The first half-side bulging portion 33 that bulges partially upward is formed, and the bulging portion 33 gradually reduces the amount of bulging in the vertical direction from the side wall 3d to the rear wall 3c. On the other hand, the upper surface of the flange 25 (divided surface portions 4c, 4b) from the side wall 5d to the rear wall 5c on one side (right side in front view) of the second half 5 corresponds to the first half-side bulged portion 33. A second half-side bulging portion 37 in which a part of the dividing surface portions 4c and 4b partially bulges upward is formed. A substantially L-shaped gas introduction passage 27 having a gas bypass passage 39 on the side walls 3d and 5d is formed between the first half-side bulging portion 33 and the second half-side bulging portion 37. Has been. The gas introduction port 28 is formed in the upper part on the bulging portions 33 and 37 side on the dividing surface portion 4 c side, and a gas introduction pipe 31 is connected to the end of the gas bypass passage portion 39. The entire gas introduction passage 27 is inclined downward from the gas introduction port 28 toward the gas discharge port 29. Gas such as engine exhaust gas is discharged from the gas discharge port 29 into the surge tank 7 through the gas introduction pipe 31, the gas introduction port 28, and the gas introduction passage 27.

The rest of the configuration is the same as in Reference Example 1, and thus the same components are denoted by the same reference numerals and description thereof is omitted.

Therefore, Oite the implementation type state is split surface 2b of the first half 3 and the second half 5, 2c, 4b, between the bulge portion 33 and 37 formed in the 4c, a gas bypass passage 39 Since the gas introduction passage 27 is formed and the gas introduction port 28 is formed on the bulging portions 33 and 37 side, the gas introduction port is provided even if the equipment is arranged around the divided surface portions 2b, 2c, 4b and 4c. Since 28 is above the divided surface portions 2b, 2c, 4b, and 4c, it is easy to assemble a gas supply hose (not shown) to the gas introduction pipe 31 connected to the gas introduction port 28. And the placement of equipment is not constrained.

Further, in the exemplary form state, split surface 2c of the bulge portion 33 and 37 corresponding portion, although 4c is inclined upward toward the gas discharge port 29, the gas introduction passage 27 between the bulged portion 33 and 37 Since the whole is formed to be inclined downward toward the gas discharge port 29, the gas is smoothly discharged to the surge tank 7 without staying in the gas introduction passage 27, and moisture in the gas is absorbed in winter. Freezing in the gas introduction passage 27 can be prevented.

  The bulging portions 33 and 37 may be provided only on the side wall 3d side, and only the gas bypass passage portion 39 may be formed between the bulging portions 33 and 37.

( Reference Example 2 )
11 and 12 show an engine intake device 1 according to Reference Example 2 of the present invention. In the second reference example , a protruding member 41 that is continuous with the flanges 23 and 25 on the rear walls 3c and 5c side of the first half 3 and the second half 5 is formed. The projecting member 41 includes a first projecting portion 41a formed integrally with the first half 3 having a split surface continuous with the split surface 2b on the rear wall 3c side of the first half 3; A second projecting portion 41b integrally formed with the second half 5 corresponding to the first projecting portion 41a and having a split surface that is continuous with the split surface 4b on the rear wall 5c side of the half body 5. It is configured. The dividing surfaces of the first protruding portion 41a and the second protruding portion 41b are joined to each other, and a part of the gas introduction passage 27 protrudes between the dividing surfaces of the first protruding portion 41a and the second protruding portion 41b. Has been. Further, the gas introduction port 28 is formed on the front end side of the protruding member 41, and a gas introduction pipe 31 is connected to the gas introduction port 28. The entire gas introduction passage 27 is inclined downward from the gas introduction port 28 toward the gas discharge port 29. Gas such as engine exhaust gas is discharged from the gas discharge port 29 into the surge tank 7 through the gas introduction pipe 31, the gas introduction port 28, and the gas introduction passage 27.

The rest of the configuration is the same as in Reference Example 1, and thus the same components are denoted by the same reference numerals and description thereof is omitted.

Therefore, in Reference Example 2 , the first protrusion 41a and the second protrusion 41b are integrally formed on the first half 3 and the second half 5, and the first protrusion 41a and the second protrusion 41b. A part of the gas introduction passage 27 is formed to protrude between the divided surface portions 2b and 4b continuous to the divided surface portions 2b and 4b of the first half 3 and the second half 5, and the gas introduction port 28 is formed as a protruding member. Since the gas inlet 28 is provided at a distance even when the equipment is arranged close to the surge tank 7, the gas inlet pipe 31 connected to the gas inlet 28 is connected to the gas inlet pipe 31. Assembly of a gas supply hose (not shown) is facilitated and workability is improved. In addition, since the entire gas introduction passage 27 is inclined downward toward the gas discharge port 29, the gas is not retained in the gas introduction passage 27 and freezing of moisture in the gas at the location is prevented in winter and the like. be able to.

  When two or more kinds of gases are introduced, a gas introduction pipe may be added so as to communicate with the gas introduction passage.

  The present invention is useful as a countermeasure for introducing gas into a surge tank in an engine intake system.

It is the perspective view which looked at the air intake device which concerns on the reference example 1 from the front side. It is the perspective view which looked at the air intake device which concerns on the reference example 1 from the rear side. In the reference example 1, it is the perspective view which looked at the 1st half of the surge tank from the lower side. In the reference example 1, it is the perspective view which looked at the 2nd half of the surge tank from the upper side. It is sectional drawing in the VV line | wire of FIG. It is sectional drawing in the VI-VI line of FIG. Is 1 equivalent diagram definitive in practice shaped state. Is 2 corresponding to FIG definitive in practice shaped state. It is sectional drawing in the IX-IX line of FIG. It is sectional drawing in the XX line of FIG. FIG. 3 is a view corresponding to FIG. 1 in Reference Example 2 . FIG. 3 is a view corresponding to FIG. 2 in Reference Example 2 .

DESCRIPTION OF SYMBOLS 1 Intake device 2 1st division surface 3 1st half body 4 2nd division surface 5 2nd half body 7 Surge tank 9 Intake inlet hole 27 Gas introduction path 28 Gas introduction port 29 Gas discharge port

Claims (1)

The upper half part having the first split surface and the lower second half part having the second split surface are joined together, and an air intake hole is formed in the rear wall of the second half body. And a plurality of branch pipes projecting from the front wall of the surge tank, the surge tank being formed by the front wall of the first half and the front wall of the second half. An intake device for an engine that mixes the intake air introduced into the surge tank through the introduction hole with at least one of exhaust gas, blow-by gas, and purge gas and supplies the mixed gas to the engine through the branch pipes,
A gas discharge port that opens into the surge tank at a position above the intake inlet hole and discharges the gas into the surge tank between the split surfaces on the rear wall side in the first half and the second half Is formed at one end of the gas introduction passage,
At the other end of the gas introduction passage, a gas introduction port for introducing the gas into the gas introduction passage is formed at a position above the gas discharge port,
The gas introduction passage is generally inclined downward from the gas introduction port toward the gas discharge port ,
Further, a first half-side bulging portion in which a part of the dividing surface partially bulges upward is formed on the rear wall-side dividing surface in the first half. A split surface on the rear wall side is formed with a second half-side bulging portion that bulges upward corresponding to the first half-side bulging portion, and the gas introduction passage is between the bulging portions. An air intake apparatus for an engine, wherein at least a part thereof is formed and the gas introduction port is formed on the bulging portion side .

Images