JP2022055989A - Blow-by gas treatment device - Google Patents

Abstract

To provide a blow-by gas treatment device which makes white smoke occurring around an outlet part due to moisture etc. in a blow-by gas less visible from the outside of a vehicle.SOLUTION: A blow-by gas treatment device 100 is used for an internal combustion engine 10 of a cab over type vehicle 1. The vehicle 1 includes a recessed part 4 recessed upward at a rear part of a floor surface 3 of a cab 2. An upper part of the internal combustion engine 10 is housed in the recessed part 4. The blow-by gas treatment device 100 includes a blow-by gas pipe 20 in which a blow-by gas B flows. The blow-by gas pipe 20 has an outlet part 30 which is open to the atmospheric air in the recessed part 4.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to blow-by gas processing equipment.

In an internal combustion engine, a blow-by gas treatment device that releases blow-by gas leaked into a crankcase from a gap between a piston and a cylinder from a blow-by gas pipe to the atmosphere is known.

In a cab-over type vehicle such as a truck, an upwardly recessed recess is provided in the rear portion of the floor surface of the cab, and the upper portion of the internal combustion engine is accommodated in this recess. On the other hand, the outlet portion of the blow-by gas pipe is arranged below this recess.

Japanese Unexamined Patent Publication No. 2016-18364

By the way, in the above blow-by gas processing apparatus, white smoke may be generated around the outlet portion of the blow-by gas pipe due to the water content and the oil content in the blow-by gas. In this case, if white smoke is visible from the outside of the vehicle, it may be mistaken that the cause of the white smoke is an abnormality of the internal combustion engine, which may lead to unnecessary maintenance.

Therefore, this disclosure was devised in view of such circumstances, and the purpose is to treat white smoke generated around the outlet due to moisture in the blow-by gas so that it is difficult to see from the outside of the vehicle. To provide the equipment.

According to one aspect of the present disclosure, it is a blow-by gas processing device used for an internal combustion engine of a cab-over type vehicle, wherein the vehicle is provided with an upwardly recessed recess in the rear portion of the floor surface of the cab, and is of the internal combustion engine. The upper portion is housed in the recess, the blow-by gas processing apparatus comprises a blow-by gas pipe through which blow-by gas flows, and the blow-by gas pipe has an outlet portion open to the atmosphere in the recess. A blow-by gas treatment device is provided.

Preferably, the outlet is directed to discharge blow-by gas toward the surface of the side wall of the recess.

Further, the outlet portion is oriented so as to discharge blow-by gas in the horizontal direction or upward from the horizontal direction.

Further, the blow-by gas pipe is arranged so as to extend from the upper side to the lower side, the lower end portion of the blow-by gas pipe is open to the atmosphere, and the outlet portion is provided at a position in the middle of the blow-by gas pipe.

Further, the cross-sectional area of the flow path of the outlet portion is larger than the minimum cross-sectional area of the flow path of the blow-by gas pipe located on the downstream side of the outlet portion.

Further, the blow-by gas processing apparatus further includes a ring member fitted inside the blow-by gas pipe located on the downstream side of the outlet portion, and the minimum flow path cross-sectional area is located in the central portion of the ring member. The cross-sectional area of the flow path of the provided orifice.

Further, the recess includes a ceiling wall extending in the front-rear direction and a rear side wall extending downward from the position of the rear end portion of the ceiling wall, and the outlet portion is an upper portion of the internal combustion engine and the rear side wall surface. Placed between and.

According to the blow-by gas treatment apparatus of the present disclosure, white smoke generated around the outlet portion due to moisture or the like in the blow-by gas can be made difficult to see from the outside of the vehicle.

It is a schematic view of the left side view of a blow-by gas processing apparatus, and is the cross-sectional view shown by line I (I) of FIG. It is the schematic of the rear view of the blow-by gas processing apparatus, and is the cross-sectional view shown by line II-II of FIG. It is an enlarged sectional view of the blow-by gas pipe shown in the part III of FIG. FIG. 3 is an enlarged cross-sectional view taken along the line IV-IV of FIG. It is a partial schematic view of the left side view which shows the blow-by gas processing apparatus of the 1st modification. It is a partial schematic view of the left side view which shows the blow-by gas processing apparatus of the 2nd modification. It is an enlarged sectional view which shows the blow-by gas pipe of the 3rd modification. It is a schematic diagram which shows the rear part of the floor surface of the cab of the 4th modification. It is a schematic diagram which shows the rear part of the floor surface of the cab of the 5th modification. It is the schematic of the left side view which shows the blow-by gas processing apparatus of the 6th modification.

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be noted that the present disclosure is not limited to the following embodiments.

First, the configuration of the internal combustion engine 10 used in the vehicle 1 will be described with reference to FIGS. 1 and 2. Each of the up, down, front, back, left, and right directions shown in the figure coincides with each direction of the vehicle 1, although it is only defined for convenience of explanation.

As shown in FIG. 1, the vehicle 1 is a cab-over type vehicle (truck in this embodiment), and is provided with a recess 4 recessed upward in the rear portion of the floor surface 3 of the cab 2. The upper portion of the internal combustion engine 10 is housed in the recess 4.

The cab 2 includes a floor panel 2a constituting the floor surface 3 and a back panel 2b extending upward from the rear end position of the floor panel 2a.

As shown in FIGS. 1 and 2, the recess 4 is formed by denting the central portion in the left-right direction in the rear portion of the floor panel 2a upward. Further, the recess 4 is formed in a U-shaped cross section in the left side view (FIG. 1) and the rear view (FIG. 2), respectively.

The recess 4 of the present embodiment includes a ceiling wall 4a extending in the front-rear direction and a rear side wall 4b extending downward from the position of the rear end portion of the ceiling wall 4a.

Further, the recess 4 has a front side wall 4c extending downward from the position of the front end portion of the ceiling wall 4a, a left side wall 4d extending downward from the position of the left end portion of the ceiling wall 4a, and a position of the right end portion of the ceiling wall 4a. It is provided with a right side wall 4e extending downward from the ceiling. In FIG. 1, reference numeral 5a indicates a front end portion of the floor panel 2a extending forward from the lower end position of the front side wall 4c. Further, in FIG. 2, reference numeral 5b indicates the left end portion of the floor panel 2a extending to the left from the lower end position of the left side wall 4d, and reference numeral 5c indicates the right end of the floor panel 2a extending to the right from the lower end position of the right side wall 4e. Shows the part.

The internal combustion engine 10 is a multi-cylinder compression ignition type internal combustion engine mounted on the vehicle 1, for example, a diesel engine. However, the internal combustion engine 10 may be of any type, type, application, etc., and may be, for example, a spark ignition type internal combustion engine such as a gasoline engine.

As shown in FIG. 1, the internal combustion engine 10 includes a cylinder block 11, a crankcase 12 integrally formed at the lower end of the cylinder block 11, a cylinder head 13 connected to the upper end of the cylinder block 11, and a cylinder head 13. A head cover 14 connected to the upper end and an oil pan 15 connected to the lower end of the crankcase 11 are provided.

Further, the internal combustion engine 10 includes a gear housing 16 connected to the rear wall of each of the cylinder block 11, the crankcase 12, and the cylinder head 13, and a flywheel housing 17 connected to the rear wall of the lower portion of the gear housing 16. , Equipped with.

The upper ends of the cylinder head 13 and the gear housing 16 are covered from above by the head cover 14. On the other hand, the lower ends of the crankcase 12 and the gear housing 16 are covered from below by the oil pan 15.

Although not shown, the cylinder block 11 is provided with a plurality of cylinders, and the cylinders accommodate pistons. A crankshaft extending in the front-rear direction is rotatably supported on the crankcase 12, and a valve operating mechanism such as a camshaft is attached to the cylinder head 13. A plurality of gears meshed with each other are housed in the gear housing 16, and the flywheel is housed in the flywheel housing 17.

As shown in FIGS. 1 and 2, the upper portion of the internal combustion engine 10 (in the present embodiment, the entire head cover 14, the upper portion of the cylinder head 13, and the upper end portion of the gear housing 16) is the ceiling wall 4a and the side walls 4b to 4e. It is housed in the recess 4 at intervals from the ceiling.

Next, the blow-by gas processing apparatus 100 of the present embodiment will be described with reference to FIGS. 1 to 4. In the figure, the dotted arrow B indicates the flow of blow-by gas, and the black-painted arrow O indicates the flow of oil.

As shown in FIG. 1, the blow-by gas processing device 100 includes a blow-by gas pipe 20 through which blow-by gas B flows. As is well known, blow-by gas is gas that leaks into the crankcase 12 from the gap between the cylinder and the piston.

The blow-by gas pipe 20 is exposed to the outside of the internal combustion engine 10. On the other hand, inside the internal combustion engine 10, an engine passage 21 through which blow-by gas B flows is provided.

The engine passage 21 passes from the inside of the crankcase 12 through the inside of the cylinder block 11 and the cylinder head 13 and extends into the head cover 14. An outlet 21a of the passage 21 in the engine is formed on the upper surface of the head cover 14. The upstream end of the blow-by gas pipe 20 is connected to the outlet 21a of the passage 21 in the engine.

The blow-by gas pipe 20 of the present embodiment is arranged so as to extend from the upper side to the lower side, and the lower end portion 20e of the blow-by gas pipe 20 is opened to the atmosphere. Specifically, the blow-by gas pipe 20 extends rearward from the outlet 21a of the engine passage 21 along the upper surface portion of the head cover 14, and then is bent downward and extends downward along the rear wall of the head cover 14. ..

The lower end portion 20e of the blow-by gas pipe 20 is arranged outside the recess 4. On the other hand, most of the blow-by gas pipe 20 other than the lower end 20e is arranged in the recess 4.

Further, the blow-by gas pipe 20 has an outlet portion 30 opened to the atmosphere in the recess 4. The outlet portion 30 is provided at a position in the middle of the blow-by gas pipe 20.

As shown in FIG. 2, the blow-by gas pipe 20 connects the upstream pipe 20a located on the upstream side, the downstream pipe 20b located on the downstream side, the upstream pipe 20a and the downstream pipe 20b in the flow direction of the blow-by gas B. It has a connecting pipe 20c and a branch pipe 20d branched from the connecting pipe.

The upstream pipe 20a and the downstream pipe 20b are made of a resin material such as rubber. On the other hand, the connecting pipe 20c and the branch pipe 20d are made of a metal material such as iron.

An oil separator 22 for removing oil from the blow-by gas B is provided in the middle of the upstream pipe 20a. The oil separator 22 is installed on the upper surface of the head cover 14.

In the oil separator 22, oil is separated from the blow-by gas B introduced therein. The oil separated from the blow-by gas B is returned into the crankcase 12 through an oil return passage (not shown).

The upstream pipe 20a and the connecting pipe 20c located on the downstream side of the oil separator 22 extend downward in order along the rear wall of the head cover 14. The downstream pipe 20c extends downward along the rear wall of the gear housing 16.

The lower end portion 20e of the downstream pipe 20c is arranged at a position below the rear side wall 4b of the recess 4 (in this embodiment, above and near the left side of the flywheel housing 17). An oil catch tank 23 for collecting oil O is provided at the lower end portion 20e of the downstream pipe 20c. However, the oil catch tank 23 may not be provided.

As shown in FIG. 3, the connecting pipe 20c and the branch pipe 20d are integrally formed and have a T-shaped cross-sectional shape as a whole. In FIG. 3, the alternate long and short dash line C1 indicates the central axis of the connecting pipe 20c, and the alternate long and short dash line C2 indicates the central axis of the branch pipe 20d.

The connecting pipe 20c extends linearly from above to below. The upper end of the connecting pipe 20c is fitted and connected to the inside of the lower end of the upstream pipe 20a, and the lower end of the connecting pipe 20c is fitted and connected to the inside of the upper end of the downstream pipe 20b.

Further, the upper end portion and the lower end portion of the connecting pipe 20c have a convex portion X formed on the outer peripheral portion thereof. The convex portion X is formed by increasing the outer diameter and inner diameter of the connecting pipe 20c by bulge processing or the like, and is formed in an annular shape extending in the circumferential direction and making one round. The lower end of the upstream pipe 20a and the upper end of the downstream pipe 20b are fixed in close contact with the convex portion X so as not to come off from the connecting pipe 20c.

The branch pipe 20d projects to the right from the axially intermediate portion of the connecting pipe 20c and extends. The outlet portion 30 of the present embodiment is formed by a branch pipe 20d.

As shown in FIG. 4, the outlet portion 30 is arranged between the upper portion of the internal combustion engine 10 (here, the rear wall of the head cover 14) and the rear side wall 4b of the recess 4.

Further, the outlet portion 30 is directed so as to discharge the blow-by gas B toward the surface direction of the rear side wall 4b of the recess 4. That is, the branch pipe 20d extends linearly along the rear side wall 4b of the recess 4.

Further, as shown in FIG. 3, the outlet portion 30 is directed so as to discharge the blow-by gas B in the horizontal direction. That is, the branch pipe 20d extends horizontally from the axially intermediate portion of the connecting pipe 20c.

The flow path cross-sectional area S1 of the outlet portion 30 is set to be larger than the minimum flow path cross-sectional area S2 of the blow-by gas pipe 20 located on the downstream side of the outlet portion 30.

Specifically, the blow-by gas processing device 100 of the present embodiment includes a ring member 40 fitted inside the blow-by gas pipe 20 located on the downstream side of the outlet portion 30. The minimum flow path cross-sectional area S2 of the present embodiment is the flow path cross-sectional area of the orifice 41 provided at the center of the ring member 40. The orifice 41 substantially narrows the flow path of the blow-by gas pipe 20.

The ring member 40 of the present embodiment is made of a metal material such as iron and is arranged inside the lower end portion of the connecting pipe 20c. Further, the outer peripheral portion of the ring member 40 is joined to and fixed to the inner peripheral portion of the connecting pipe 20c by welding or the like. However, the ring member 40 may be formed of a resin material such as plastic or rubber, or may be fixed by being press-fitted into the inner peripheral portion of the connecting pipe 20c, for example.

As shown in FIG. 1, in the present embodiment, while the internal combustion engine 10 is in operation, the blow-by gas B in the crankcase 12 flows through the in-engine passage 21 and the upstream pipe 20a of the blow-by gas pipe 20 in order, and is a connecting pipe. Introduced in 20c. The blow-by gas B introduced into the connecting pipe 20c is released to the atmosphere from the outlet portion 30, flows through the downstream pipe 20b, and is released to the atmosphere from the downstream end 20e.

However, as shown in FIG. 3, the flow path cross-sectional area S1 of the outlet portion 30 is set to be larger than the minimum flow path cross-section S2 of the blow-by gas pipe 20 located on the downstream side of the outlet portion 30. Most of the blow-by gas B introduced into the connecting pipe 20c is released to the atmosphere from the outlet portion 30.

Further, as shown in FIGS. 1 and 4, the outlet portion 30 of the present embodiment is arranged in the recess 4. Therefore, even when white smoke W is generated around the outlet portion 30 due to the moisture and oil content in the blow-by gas B, the side wall of the recess 4 (particularly, in the present embodiment, the rear side wall 4b) is white. You can cover up the smoke.

Therefore, in the blow-by gas processing apparatus 100 of the present embodiment, the white smoke generated around the outlet portion 30 can be made difficult to see from the outside of the vehicle 1. As a result, it is possible to prevent unnecessary maintenance from being performed by misidentifying that the cause of the white smoke is an abnormality of the internal combustion engine 10.

In addition to the above, in the present embodiment, the following actions (1) to (6) also exist. In the following (1) and (2), the operation and effect of the present embodiment will be described as compared with the modified examples. In these modifications, the same reference numerals are used for the same or common components as those in the above embodiment, and detailed description thereof will be omitted.

(1) As shown in FIG. 5, as a modification of the present embodiment, a first modification in which the outlet portion 30 is directed to discharge blow-by gas B toward the rear side wall 4b of the recess 4 is considered. Be done.

However, in this case, the white smoke W generated around the outlet portion 30 collides with the blow-by gas B together with the rear side wall 4b and is turned downward, and flows under the rear side wall 4b to the rear of the cab 2. Therefore, it may be visible from the outside of the vehicle 1.

On the other hand, as shown in FIG. 4, the outlet portion 30 of the present embodiment is directed so as to discharge the blow-by gas B toward the surface direction of the rear side wall 4b of the recess 4. Therefore, it is possible to prevent the white smoke W from colliding with the rear side wall 4b and being turned downward and flowing under the rear side wall 4b to the rear of the cab 2. As a result, it is possible to suppress the white smoke W from being seen from the outside of the vehicle 1.

(2) As shown in FIG. 6, as a modification of the present embodiment, a second modification in which the outlet portion 30 is directed to discharge the blow-by gas B downward from the horizontal direction can be considered.

However, in this case, the white smoke W generated around the outlet portion 30 can be seen from the outside of the vehicle 1 by being flowed downward together with the blow-by gas B, passing through the rear side wall 4b and flowing behind the cab 2. There is sex.

On the other hand, as shown in FIG. 3, the outlet portion 30 of the present embodiment is oriented so as to discharge the blow-by gas B in the horizontal direction. Therefore, it is possible to prevent the white smoke W from flowing downward and flowing behind the cab 2 under the rear side wall 4b. As a result, it is possible to suppress the white smoke W from being seen from the outside of the vehicle 1.

(3) As described above, in the present embodiment, the flow path cross-sectional area S1 of the outlet portion 30 is set to be larger than the minimum flow path cross-sectional area S2 of the blow-by gas pipe 20 located on the downstream side of the outlet portion 30. Therefore, most of the blow-by gas B is discharged from the outlet portion 30. As a result, the discharge of blow-by gas B from the lower end portion 20e of the blow-by gas pipe 20 can be suppressed. As a result, it is possible to suppress the generation of white smoke around the lower end portion 20e, and it is possible to suppress the white smoke from being seen from the outside of the vehicle 1.

(4) Further, in the present embodiment, the orifice 41 having the minimum flow path cross-sectional area S2 can be easily formed by simply fitting the ring member 40 inside the blow-by gas pipe 20 located on the downstream side of the outlet portion 30. Can be provided in.

(5) In the present embodiment, as shown in FIG. 1, the blow-by gas pipe 20 is arranged so as to extend from the upper side to the lower side, and the outlet portion 30 is provided at a position in the middle of the blow-by gas pipe 20. Therefore, the oil O that cannot be completely separated by the oil separator 22 and remains in the blow-by gas B adheres to the inside of the blow-by gas pipe 20 and flows down the inside of the blow-by gas pipe 20 to be discharged from the lower end portion 20e. As a result, the discharge of oil O from the outlet portion 30 can be suppressed. Further, the oil O discharged from the lower end portion 20e can be collected by the oil catch tank 23.

(6) In the blow-by gas pipe 20 located on the downstream side of the outlet portion 30, the flow of the blow-by gas B is obstructed by the ring member 40. As a result, the oil in the blow-by gas B can be positively adhered to the upper end surface of the ring member 40 and the inner wall of the blow-by gas pipe 20 around the upper end surface, and the oil content in the blow-by gas B can be reduced. As a result, the generation of white smoke around the outlet portion 30 can be suppressed.

Although the embodiments of the present disclosure have been described in detail above, the present disclosure can be made into the following modifications or combinations thereof in addition to the above-mentioned first and second modifications.

(Third modification example)
As shown in FIG. 7, the outlet portion 30 of the third modification is directed so as to discharge the blow-by gas B upward from the horizontal direction. Specifically, the branch pipe 20d of the third modification extends from the intermediate portion in the axial direction of the connecting pipe 20c so as to be inclined upward with respect to the horizontal direction.

According to the third modification, the white smoke W generated around the outlet portion 30 can be flowed diagonally upward together with the blow-by gas B. As a result, it is possible to reliably suppress the white smoke W from going under the rear side wall 2b and being seen from the outside of the vehicle 1.

Further, in the third modification, when the oil O in the blow-by gas B adheres to the branch pipe 20d, the oil O flows down the branch pipe 20d and is introduced into the connecting pipe 20c. As a result, it is possible to suppress the oil O from being discharged from the outlet portion 30.

(Fourth modification)
As shown in FIG. 8, the rear side wall 4b of the recess 4 may be provided as a separate body from the floor panel 2a. Specifically, the rear end portion of the floor panel 2a of the fourth modification is terminated in a horizontal state, and the rear side wall 4b of the recess 4 is attached to the rear end portion of the floor panel 2a and hung down. It is formed by the cover member 2c. The rear end of the recess 4 is closed by the cover member 2c.

(Fifth modification)
As shown in FIG. 9, the rear end portion of the floor panel 2a of the fifth modification is terminated in a horizontal state and connected to the front surface of the back panel 2b. The lower end of the back panel 2b extends below the rear end of the floor panel 2a to form the rear side wall 4b of the recess 4. The rear end of the recess 4 is closed by the lower end of the back panel 2b.

(6th modification)
As shown in FIG. 10, the outlet portion 30 may be arranged at an arbitrary position in the recess 4. The outlet portion 30 of the sixth modification is arranged between the upper portion of the internal combustion engine 1 (here, the front wall of the head cover 14) and the front side wall 4c of the recess 4, and blow-by gas is directed toward the surface of the front side wall 4c. Directed to eject B.

According to the sixth modification, the white smoke generated around the outlet portion 30 can be covered with the front side wall 4c of the recess 4. Further, in the sixth modification, the white smoke can be made difficult to see from the outside of the vehicle 1 without providing the rear side wall 4b of the recess 4.

Although not shown, the outlet portion 30 can be arranged, for example, between the upper portion of the internal combustion engine 1 (here, the left side wall of the head cover 14) and the left side wall surface 4d of the recess 4.

(7th modification)
Although not shown, the blow-by gas pipe 20 may not be provided with the branch pipe 20d. In this case, the outlet portion 30 is formed by a simple hole formed in the side wall portion of the connecting pipe 20c.

Further, the blow-by gas pipe 20 does not have to be provided with the downstream pipe 20b and the connecting pipe 20c. In this case, the outlet portion 30 is formed by the lower end portion of the upstream pipe 20a or by a hole provided in the side wall portion of the upstream pipe 20a.

(8th modification)
The blow-by gas pipe 20 may be formed of any material, and the upstream pipe 20a, the downstream pipe 20b, the connecting pipe 20c, and the branch pipe 20d may be integrally formed.

1 Cab-over type vehicle 2 Cab 3 Floor surface 4 Recess 4a Ceiling wall 4b Rear side wall 10 Internal combustion engine 20 Blow-by gas pipe 20e Lower end 30 Outlet 40 Ring member 41 Orifice 100 Blow-by gas processing device B Blow-by gas O oil

Claims (7)

A blow-by gas processing device used in the internal combustion engine of a cab-over type vehicle.
The vehicle has an upwardly recessed recess at the rear of the floor of the cab.
The upper part of the internal combustion engine is housed in the recess.
The blow-by gas processing device includes a blow-by gas pipe through which blow-by gas flows.
The blow-by gas treatment device is characterized in that the blow-by gas pipe has an outlet portion opened to the atmosphere in the recess. The blow-by gas processing apparatus according to claim 1, wherein the outlet portion is directed so as to discharge blow-by gas toward the surface direction of the side wall of the recess. The blow-by gas processing apparatus according to claim 1 or 2, wherein the outlet portion is directed to discharge blow-by gas in a horizontal direction or upward above the horizontal direction. The blow-by gas pipe is arranged so as to extend from the upper side to the lower side.
The lower end of the blow-by gas pipe is open to the atmosphere.
The blow-by gas processing apparatus according to any one of claims 1 to 3, wherein the outlet portion is provided at a position in the middle of the blow-by gas pipe. The blow-by gas processing apparatus according to claim 4, wherein the flow path cross section of the outlet portion is larger than the minimum flow path cross section of the blow-by gas pipe located on the downstream side of the outlet portion. A ring member fitted inside the blow-by gas pipe located on the downstream side of the outlet portion is further provided.
The blow-by gas treatment apparatus according to claim 5, wherein the minimum flow path cross section is the flow path cross section of an orifice provided in the center of the ring member. The recess comprises a ceiling wall extending in the front-rear direction and a rear side wall extending downward from the position of the rear end portion of the ceiling wall.
The blow-by gas processing apparatus according to any one of claims 1 to 6, wherein the outlet portion is arranged between the upper portion of the internal combustion engine and the rear side wall surface.

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