JP6407802B2 - engine - Google Patents

Description

  The present invention relates to an engine, and more particularly, to an engine that can reduce oil consumption.

  2. Description of the Related Art Conventionally, there is an engine including a cylinder head, a cylinder head cover assembled on the upper part of the cylinder head, a rocker arm covered with the cylinder head cover, and a breather chamber disposed in the cylinder head cover (see, for example, Patent Document 1). ).

  According to this type of engine, the oil splashed by the rocker arm passes through the breather chamber together with the blow-by gas, and the oil is separated from the blow-by gas in the breather chamber, so that the oil outflow to the outside of the cylinder head cover is suppressed, and the oil consumption There is an advantage that can be suppressed.

  However, the thing of patent document 1 has a problem because the blow-by gas inlet is opened in the bottom wall of the breather chamber, and the breather chamber bottom wall is formed flat.

JP-A-11-210437 (see FIGS. 1 to 4)

<< Problem >> Oil consumption may increase.
In Patent Document 1, oil splashed by the rocker arm rides on the flow of blow-by gas along the bottom wall of the breather chamber, easily enters the blow-by gas inlet, and the amount of oil entering the breather chamber becomes excessive. Oil separation in the chamber was not in time, and oil consumption could increase due to oil spilling out of the cylinder head cover.

  The subject of this invention is providing the engine which can reduce oil consumption.

  As a result of research, the inventors of the present invention opened the blow-by gas inlet in the bottom wall of the breather chamber, and directed the peripheral wall of the oil discharge guide chamber between the rocker arm on the blow-by gas outlet side and the blow-by gas inlet. By projecting downward from the bottom wall of the breather chamber, even if the oil bounced up by the rocker arm on the blow-by gas outlet side rides on the flow of blow-by gas along the bottom wall of the breather chamber, this flow will flow in the oil discharge guide chamber. It is blocked by the peripheral wall, the amount of oil entering the blow-by gas inlet is reduced, the amount of oil entering the breather chamber is optimized, the outflow of oil to the outside of the cylinder head cover is suppressed, and oil consumption can be reduced. Discovered and led to this invention.

Invention specific matters of the invention according to claim 1 are as follows.
As illustrated in FIG. 2, a cylinder head (1), a cylinder head cover (2) assembled to the top of the cylinder head (1), a rocker arm (3) covered with the cylinder head cover (2), and a cylinder head cover (2) In an engine provided with a breather chamber (4) arranged in
2 and 3, the breather chamber (4) has a blow-by gas inlet (5) at one end in the front-rear direction and a blow-by at the other end in the front-rear direction, with the longitudinal direction of the cylinder head cover (2) as the front-rear direction. The gas outlet (6) is provided with an oil discharge guide chamber (7) at an intermediate position in the front-rear direction,
2 and 4, the blow-by gas inlet (5) is opened in the bottom wall (4a) of the breather chamber (4), and the peripheral wall (7a) of the oil discharge guide chamber (7) is the blow-by gas outlet. (6) Projecting downward from the bottom wall (4a) of the breather chamber (4) toward the rocker arm (3) on the side and the blow-by gas inlet (5) ,
As illustrated in FIGS. 10A, 10C, and 12A, the breather chamber (4) includes an oil discharge portion (16) below the oil discharge guide chamber (7), and the cylinder head (1). Has an oil sump (17), and the oil discharge port (16a) of the oil discharge part (16) is immersed in the separated oil (18) stored in the oil sump (17),
As shown in FIG. 2, a predetermined rocker arm located on the opposite side of the blow-by gas inlet (5) in the front-rear direction with the oil discharge guide chamber (7) interposed between the plurality of rocker arms (3) (3). 6 and 7, as shown in FIGS. 6 and 7, the peripheral wall (7a) of the oil discharge guide chamber (7) is viewed from a direction parallel to the front-rear direction, and the input rocking of the predetermined rocker arm (3). Projecting downward from the bottom wall (4a) of the breather chamber (4) to a position overlapping the moving end (3a), the cylindrical oil discharge part (16) is seen in a direction parallel to the front-rear direction. The engine is arranged at a position overlapping the push rod (33) of the predetermined rocker arm (3).

(Invention of Claim 1)
The invention according to claim 1 has the following effects.
<Effect> Oil consumption can be reduced.
As illustrated in FIG. 2, the oil splashed by the rocker arm (3) on the blow-by gas outlet (6) side rides on the flow of the blow-by gas (11) along the bottom wall (4a) of the breather chamber (4). However, this flow is blocked by the peripheral wall (7a) of the oil discharge guide chamber (7), the amount of oil entering the blow-by gas inlet (5) is reduced, and the amount of oil entering the breather chamber (4) is optimized. The oil outflow to the outside of the cylinder head cover (2) is suppressed, and the oil consumption can be reduced.

<Effect> It is possible to reduce engine noise emission from the cylinder head cover.
As illustrated in FIG. 2, the peripheral wall (7 a) of the oil discharge guide chamber (7) projects downward from the bottom wall (4 a) of the breather chamber (4), so that the bottom of the breather chamber (4) The rigidity of the wall (4a) is increased, and the bottom wall (4a) is less likely to vibrate, and emission of engine noise from the cylinder head cover (2) through this vibration can be reduced.
<Effect> Blow-by gas does not enter the oil discharge guide chamber through the oil discharge port of the oil discharge section.
As illustrated in FIGS. 10 (A), (C) and 12 (A), the oil discharge port (16a) of the oil discharge section (16) is immersed in the separated oil (18) stored in the oil reservoir (17). Therefore, the oil discharge port (16a) of the oil discharge part (16) is blocked by the separated oil (18), and the blow-by gas (11) is discharged through the oil discharge port (16a) of the oil discharge part (16). Do not enter the guide room (7).

(Invention of Claim 2)
The invention according to claim 2 has the following effect in addition to the effect of the invention according to claim 1.
<Effect> Blow-by gas oil separation is promoted.
As illustrated in FIG. 3, the breather chamber (4) includes an inlet-side oil separation chamber (9) having a blow-by gas inlet (5) and a blow-by gas bypass passage (10). ) Is continuously separated in the inlet side oil separation chamber (9) and the blowby gas bypass passage (10), and the oil separation of the blowby gas (11) is promoted.

(Invention of Claim 3)
The invention according to claim 3 has the following effect in addition to the effect of the invention according to claim 2.
<Effect> The separated oil can be promptly guided to the oil discharge guide chamber (7).
As illustrated in FIGS. 3 and 9 (A), the separation oil guide passage (13) has a start end portion (13a) disposed in the inlet side oil separation chamber (9) and an intermediate portion (13b) as a blow-by gas bypass passage. (10) is disposed at the start end (10a), and the terminal end (13c) passes through the lower part of the partition wall (12) and is led out to the oil discharge guide chamber (7). The separation oil (18) can be promptly guided to the oil discharge guide chamber (7).

<Effect> Blow-by gas does not short-circuit.
As illustrated in FIGS. 3 and 9 (A), the end portion (13c) of the separation oil guide path (13) passes through the lower part of the partition wall (12) and is led out to the oil discharge guide chamber (7). The end portion (13c) of the separation oil guide passage (13) that passes under the partition wall (12) is blocked by the separation oil (18), and is blown into the oil discharge guide chamber (7) through the separation oil guide passage (13). There is no short circuit of the gas (11).

(Invention of Claim 4)
The invention according to claim 4 has the following effect in addition to the effect of the invention according to claim 3.
<Effect> Separation oil is promptly induced.
As illustrated in FIGS. 3 and 8 (A) to (C), the separation oil guide passage (13) is constituted by the groove (14), so that the inlet side oil separation chamber (9) and the blow-by gas bypass passage ( The separated oil (18) separated at the starting end (10a) of 10) quickly flows into the groove (14) from the upper opening of the groove (14) and passes through the groove (14) with a small passage resistance. Then, the separated oil (18) is promptly guided.

<Effect> The separated oil (18) is hardly re-misted.
As illustrated in FIGS. 3 and 8 (A) to (C), when the separation oil guiding path (13) is constituted by the groove (14), the separation oil (18) is separated from the separation oil guiding path (13). When passing, there is a risk of contact with the blow-by gas (11) passing through the blow-by gas bypass passage (10). However, as described in the effect of claim 3, the separation oil guiding path (13) should be formed short. Therefore, the separated oil (18) is less likely to come into contact with the blow-by gas (11) and is not easily re-misted. Further, even when the mist is re-misted, it is re-separated by the downstream blow-by gas bypass passage (10). For this reason, the separated oil (18) is hardly re-misted.

(Invention according to claim 5)
The invention according to claim 5 has the following effect in addition to the effect of the invention according to claim 3.
<Effect> The separated oil is hardly re-misted.
As illustrated in FIGS. 9A and 9B, since the separation oil guide path 13 is constituted by a pipe 15, the upper surface of the separation oil guide path 13 is covered and the separation oil guide path is formed. The separated oil (18) introduced into (13) does not come into contact with the blow-by gas (11) passing through the blow-by gas bypass passage (10), and the separated oil (18) is not easily re-misted.

(Invention of Claim 6)
The invention according to claim 6 has the following effects in addition to the effects of the invention according to any one of claims 3 to 5.
<Effect> Separation oil is discharged smoothly.
As illustrated in FIG. 10A, the oil discharge guide surface (7b) is inclined downward from the terminal end portion (13c) of the separation oil guide path (13) toward the oil discharge portion (16). The separated oil (18) is discharged smoothly.
The reason is that a continuous oil film is formed by the separated oil (18) flowing down the slope on the downwardly inclined surface of the oil discharge guide surface (7b), and the subsequent separated oil (18) smoothly smooths the surface of the oil film. Presumed to slip down.

(Invention of Claim 7)
The invention according to claim 7 has the following effects in addition to the effects of the invention according to any one of claims 3 to 5.
<Effect> When the engine is inclined, the separated oil does not easily flow backward through the oil discharge guide surface.
As illustrated in FIG. 11A, the oil discharge guide surface (7b) is composed of a stepped zigzag surface that descends from the terminal end portion (13c) of the separated oil guide path (13) to the oil discharge portion (16). Therefore, even if the engine is inclined toward the oil discharge guide surface (7b), the separated oil (18) is accumulated in the recess of the oil discharge guide surface (7b) formed by the zigzag surface, and the separated oil ( 18) hardly flows back through the oil discharge guide surface (7b).

It is a disassembled perspective view of the cylinder head cover of the engine which concerns on embodiment of this invention, and the bottom wall of a breather chamber. It is an upper section side view of an engine concerning an embodiment of the present invention. It is the III-III sectional view taken on the line of FIG. It is the IV-IV sectional view taken on the line of FIG. It is the VV sectional view taken on the line of FIG. It is the VI-VI sectional view taken on the line of FIG. It is the VII-VII sectional view taken on the line of FIG. FIGS. 8A and 8B are diagrams illustrating a separated oil guiding path used in an engine according to an embodiment of the present invention, FIG. 8A is a basic example, FIG. 8B is a first modified example, and FIG. 8C is a second modified example. It is. FIGS. 9A and 9B are diagrams for explaining a third modified example of the separated oil guiding path used in the engine according to the embodiment of the present invention, FIG. 9A is a diagram corresponding to FIG. 3, and FIG. 9B is a diagram corresponding to FIG. It is a figure explaining the basic example of the oil discharge guide chamber used with the engine which concerns on embodiment of this invention, FIG. 10 (A) is a vertical front view, FIG.10 (B) is a B direction arrow line view of FIG.10 (A). FIG. 10C is a cross-sectional view taken along line CC of FIG. FIGS. 11A and 11B are diagrams illustrating a modified example of the oil discharge guide chamber used in the engine according to the embodiment of the present invention. FIG. 11A is a longitudinal front view of the first modified example, and FIG. FIG. 11C is a longitudinal front view of the third modification, and FIG. 11D is a view in the direction of arrow D in FIG. 11C. FIGS. 12A and 12B are views for explaining first to third modified examples of the oil discharger used in the engine according to the embodiment of the present invention. FIG. 12A is a longitudinal front view of the first modified example, and FIG. 12A is a cross-sectional view taken along line BB in FIG. 12A, FIG. 12C is a longitudinal front view of the second modification, FIG. 12D is a view in the direction of arrow D in FIG. 12C, and FIG. FIG. 12 (D) and FIG. 12 (F) in the valve open state are longitudinal front views of the third modification. FIGS. 13A and 13B are views for explaining fourth and fifth modified examples of the oil discharger used in the engine according to the embodiment of the present invention. FIG. 13A is a longitudinal front view of the fourth modified example, and FIG. (A) BB sectional drawing, FIG.13 (C) is a vertical front view of a 5th modification. FIGS. 14A and 14B are diagrams illustrating a texture used in an engine according to an embodiment of the present invention. FIG. 14A is a basic example, FIG. 14B is a first modification, and FIG. 14C is a second modification.

  1 to 14 are views for explaining an engine according to an embodiment of the present invention. In this embodiment, a vertical in-line two-cylinder diesel engine will be described.

The outline of the engine of this embodiment is as follows.
As shown in FIG. 2, the cylinder head (1) is assembled to the upper part of the cylinder block (not shown), and the cylinder head cover (2) is assembled to the upper part of the cylinder head (1). The installation direction of the crankshaft (not shown) is the front-rear direction, and one of them is the front and the other is the rear.
An oil pan (not shown) is assembled to the lower part of the cylinder block (not shown).

  As shown in FIG. 2, the cylinder head (1) is provided with a vortex chamber (not shown), and a fuel injection pump (not shown) and a fuel injection pipe (not shown) and fuel injection are provided in the vortex chamber (not shown). Fuel is injected through a nozzle (not shown).

  As shown in FIG. 7, an intake and exhaust valve device (32) is accommodated in the cylinder head cover (2), and this valve device (32) is driven by the valve operating device (33). The valve operating device (33) includes a valve operating cam (not shown), a tappet (not shown), a push rod (33c), and a rocker arm (3). The push rod (33c) is accommodated in the push rod chamber (33d) shown in FIG. The blow-by gas (11) in the crankcase (not shown) enters the cylinder head cover (2) through the push rod chamber (33d).

As shown in FIG. 1, the bottom wall (4a) of the breather chamber (4) is assembled into the cylinder head cover (2) from the lower side, and the oil supply hole (2b) is formed in the ceiling wall (2a) of the cylinder head cover (2). The oil supply hole (2b) is closed by a detachable lid (2c).
The bottom wall (4a) of the breather chamber (4) is made of synthetic resin. The cylinder head cover (2) is made of aluminum die casting.

As shown in FIG. 2, the engine includes a cylinder head (1), a cylinder head cover (2) assembled to the top of the cylinder head (1), and a rocker arm (3) covered with the cylinder head cover (2). And a breather chamber (4) disposed in the cylinder head cover (2).
For this reason, the oil splashed by the rocker arm (3) passes through the breather chamber (4) together with the blow-by gas (11), and the oil is separated from the blow-by gas (11) in the breather chamber (4). ) Outflow of oil to the outside is suppressed, and oil consumption can be suppressed.

As shown in FIGS. 2 and 3, the breather chamber (4) has a blow-by gas inlet (5) on the front side and a blow-by gas outlet (6) on the rear side with the longitudinal direction of the cylinder head cover (2) as the front-rear direction. An oil discharge guide chamber (7) is provided at each intermediate position in the front-rear direction. The blow-by gas inlet (5) may be disposed on the rear side, and the blow-by gas outlet (6) may be disposed on the front side.
2 and 4, the blow-by gas inlet (5) is opened to the bottom wall (4a) of the breather chamber (4), and the peripheral wall (7a) of the oil discharge guide chamber (7) is connected to the blow-by gas outlet ( 6) Projecting downward from the bottom wall (4a) of the breather chamber (4) toward the rocker arm (3) on the side and the blow-by gas inlet (5).

  Therefore, as shown in FIG. 2, the oil splashed by the rocker arm (3) on the blow-by gas outlet (6) side flows into the flow of the blow-by gas (11) along the bottom wall (4a) of the breather chamber (4). Even if it gets on, this flow is blocked by the peripheral wall (7a) of the oil discharge guide chamber (7), the amount of oil entering the blow-by gas inlet (5) is reduced, and the amount of oil entering the breather chamber (4) is appropriate. Thus, the outflow of oil to the outside of the cylinder head cover (2) is suppressed, and oil consumption can be reduced. Further, the rigidity of the bottom wall (4a) of the breather chamber (4) is increased, the bottom wall (4a) is less likely to vibrate, and the emission of engine noise from the cylinder head cover (2) through this vibration can be reduced. it can.

As shown in FIGS. 2 and 3, a reed valve (5a) is attached to the blow-by gas inlet (5). The opened reed valve (5a) is received by the stop plate (5b). In the inlet side oil separation chamber (9), the oil mist contained in the blowby gas (11) entering from the blowby gas inlet (5) collides with the reed valve (5a) to separate the oil, and the oil mist is separated from the chamber wall. Condensate and separate oil.
A baffle plate (45) protrudes downward from the bottom wall (4a) of the breather chamber (4) between the rocker arm (3) on the blow-by gas inlet (5) side and the blow-by gas inlet (5). Yes. For this reason, the flow of the blow-by gas (11) along the bottom wall (4a) of the breather chamber (4) is blocked by the baffle plate (45), and the amount of oil entering the blow-by gas inlet (5) is reduced. The baffle plate (45) is integrally formed with the bottom wall (4a) of the breather chamber (4).

As shown in FIGS. 2 and 3, the breather chamber (4) includes an inlet-side oil separation chamber (9) having a blow-by gas inlet (5) and a blow-by gas bypass passage (10). The blow-by gas (11) that has exited 9) is introduced into the oil discharge guide chamber (7) via the blow-by gas bypass passage (10).
Therefore, the blow-by gas (11) is continuously oil-separated in the inlet-side oil separation chamber (9) and the blow-by gas bypass passage (10), and the oil separation of the blow-by gas (11) is promoted.
The inlet side oil separation chamber (9) is formed long in the front-rear direction, and the blow-by gas bypass passage (10) is formed long in the lateral direction, and these are mutually connected at the rear opening (9a) of the inlet side oil separation chamber (9). In the blow-by gas bypass passage (10), oil mist contained in the blow-by gas (11) entering from the opening (9a) is condensed on the passage wall to perform oil separation.
The first partition wall (46) that partitions the inlet side oil separation chamber (9) and the blow-by gas bypass passage (10) is formed to be long in the lateral direction, and is integrally formed with the cylinder head cover (2) to form the ceiling wall (2a). It protrudes downward from.

As shown in FIG. 3, the breather chamber (4) includes a partition wall (12) that partitions the blow-by gas bypass passage (10) and the oil discharge guide chamber (7), and a separation oil guide passage (13). The passage (13) has a start end (13a) disposed in the inlet side oil separation chamber (9), an intermediate portion (13b) disposed in the start end (10a) of the blow-by gas bypass passage (10), and a terminal end ( 13c) passes under the partition wall (12) and is led out to the oil discharge guide chamber (7).
For this reason, the separation oil guiding path (13) can be formed short, and the separation oil (18) can be quickly guided to the oil discharge guide chamber (7).
Further, the end portion (13c) of the separation oil guide passage (13) that passes through the lower part of the partition wall (12) is blocked by the separation oil (18), and the oil discharge guide chamber (7) is filled via the separation oil guide passage (13). The blow-by gas (11) does not short-circuit.
A second partition wall (12) that divides the blow-by gas bypass passage (10) and the oil discharge guide chamber (7) is formed to be long in the horizontal direction, and projects downward from the ceiling wall (2a) by being integrally formed with the cylinder head cover (2). It is installed.

As shown in FIG. 3, the separation oil guiding path (13) is constituted by a groove (14).
For this reason, the separated oil (18) separated at the inlet end oil separation chamber (9) and the start end (10a) of the blow-by gas bypass passage (10) is introduced into the groove (14) from the upper opening of the groove (14). The oil immediately flows and passes through the groove (14) with a small passage resistance, so that the separated oil (18) is promptly guided.
Further, when the separation oil guiding path (13) is constituted by the groove (14), the separation oil (18) passes through the blow-by gas bypass path (10) when passing through the separation oil guiding path (13). Although there is a possibility of contact with the blow-by gas (11), as described above, since the separation oil guide path (13) can be formed short, the separation oil (18) is difficult to contact with the blow-by gas (11). , Difficult to re-mist. Further, even when the mist is re-misted, it is re-separated by the downstream blow-by gas bypass passage (10). For this reason, the separated oil (18) is hardly re-misted.

In the basic example shown in FIG. 8A, the groove (14) has a semicircular cross section.
The groove (14) is formed in a wedge shape in cross section, as in the first modification shown in FIG. 8 (B), and the inner bottom surface becomes gradually shallower toward the end portion (10b) side of the blow-by gas bypass passage (10). It may be.
The groove (14) is formed in a cross-sectional flask shape as in the second modification shown in FIG. 8 (C), the lower half (14a) is wider than the upper half (14b), and a wide passage is cut off. In the lower half (14a) of the area, the separation oil (18) is promptly guided, and in the upper half (14b) of the narrow opening area, the separation oil (18) and the blow-by gas (11) are less likely to come into contact with each other. The separated oil (18) may be less likely to be re-misted with the gas (11).

The separation oil guiding path (13) may be configured by a pipe (15) as in the third modification shown in FIGS. 9 (A) and 9 (B).
In this case, the upper surface of the separation oil guiding path (13) is covered, and the separation oil (18) introduced into the separation oil guiding path (13) is separated from the blowby gas (11) passing through the blowby gas bypass path (10). The separated oil (18) is not easily re-misted in the blowby gas bypass passage (10) without contact.
The pipe (15) can also be provided on the terminal end (10b) side of the blow-by gas bypass passage (10). The separation oil guiding path (13) of the pipe (15) disposed on the terminal end (10b) side of the blowby gas bypass passage (10) has the start end (13a) disposed in the inlet side oil separation chamber (9). The intermediate portion (13b) is disposed at the end portion (10b) of the blow-by gas bypass passage (10), and the end portion (13c) passes through the lower side of the partition wall (12) and is led out to the oil discharge guide chamber (7). ing.

As shown in FIG. 10 (A), the breather chamber (4) has an oil discharge portion (16) at the lower portion of the oil discharge guide chamber (7), and the oil discharge guide chamber (7) has an oil discharge guide surface on the inner periphery. (7b), and the oil discharge guide surface (7b) is inclined downward from the end portion (13c) of the separated oil guide path (13) toward the oil discharge portion (16).
For this reason, the separation oil (18) is smoothly discharged.
The reason is that a continuous oil film is formed by the separated oil (18) flowing down the slope on the downwardly inclined surface of the oil discharge guide surface (7b), and the subsequent separated oil (18) smoothly smooths the surface of the oil film. Presumed to slip down.
In the basic example shown in FIG. 9A, the oil discharge guide surface (7b) is a flat inclined surface having no irregularities.
The oil discharge guide chamber (7) is long in the lateral direction, and the chamber wall of the oil discharge guide chamber (7) and the oil discharge portion (16) are integrally formed with the bottom wall (4a) of the breather chamber (4). , Projecting downward from the bottom wall (4a).

The oil discharge guide surface (7b) is a stepped zigzag that descends from the end portion (13c) of the separation oil guide path (13) to the oil discharge portion (16) as in the first modification shown in FIG. It may be configured by a surface.
In this case, even if the engine is inclined toward the oil discharge guide surface (7b), the separated oil (18) is accumulated in the recess of the oil discharge guide surface (7b) formed by the zigzag surface, and the separated oil (18 ) Hardly flows back through the oil discharge guide surface (7b).

The oil discharge guide surface (7b) is seen from the front side to the oil discharge portion (16) from the end portion (13c) of the separated oil guide path (13) as in the second modification shown in FIG. It may be composed of a curved surface of a cycloid curve having a tangent line that faces downward.
In this case, the separation oil (18) is discharged smoothly.
The reason is that a continuous oil film is formed on the surface of the downward curved surface of the oil discharge guide surface (7b) by the separated oil (18) flowing down the downward curved surface, and the subsequent separated oil (18) is formed on the surface of the oil film. It is estimated that it slips down smoothly in the shortest distance.

The oil discharge guide surface (7b), as in the third modification shown in FIGS. 11 (C) and (D), extends downward from the terminal end portion (13c) of the separated oil guide path (13 ) toward the oil discharge portion (16). It may be a narrow funnel-shaped curved surface.
In this case, there is an advantage that the separated oil (18) flows down smoothly on the downwardly inclined oil discharge guide surface (7b) no matter which direction the engine is inclined.

As shown in FIGS. 10 (A) and 10 (C), the breather chamber (4) is provided with an oil discharge portion (16) below the oil discharge guide chamber (7), and the cylinder head (1) has an oil sump (17). The oil discharge port (16a) of the oil discharge section (16) is immersed in the separated oil (18) stored in the oil reservoir (17).
For this reason, the oil discharge part (16) is blocked by the separated oil (18), and the trouble that the blow-by gas (11) enters the oil discharge guide chamber (7) through the oil discharge part (16) is prevented.
As shown in FIG. 2, a predetermined rocker arm (on the opposite side in the front-rear direction with respect to the blow-by gas inlet (5), with the oil discharge guide chamber (7) sandwiched between the plurality of rocker arms (3) (3). 6 and 7, as shown in FIGS. 6 and 7, the peripheral wall (7 a) of the oil discharge guide chamber (7) is viewed from a direction parallel to the front-rear direction, and the input rocking end of the predetermined rocker arm (3) The cylindrical oil discharge portion (16) protrudes downward from the bottom wall (4a) of the breather chamber (4) to a position overlapping with the portion (3a), and the cylindrical oil discharge portion (16) is seen in a direction parallel to the front-rear direction. It arrange | positions in the position which overlaps with the push rod (33) of a predetermined rocker arm (3).

In the basic example shown in FIGS. 10 (A) and 10 (C), the oil discharge portion (16) has a cylindrical peripheral surface shape with no unevenness.
As in the first modification shown in FIGS. 12 (A) and 12 (B), the oil discharge portion (16) includes a flow-down oil guide groove (16b) along the axial length direction on the inner peripheral surface of the cylindrical peripheral surface shape. It may be. A plurality of flow-down oil guide grooves (16b) are formed at predetermined intervals in the circumferential direction.
In this case, the separated oil (18) flowing down the oil discharge portion (16) is guided vertically downward by the flow-down oil guide groove (16b), and is smoothly discharged from the oil discharge portion (16).

The oil discharge part (16) is provided with a check valve (34) at the lower end as in the second modification shown in FIGS. 12 (C) to (E), and the pressure difference between the inside and outside of the breather chamber (4). When the check valve (34) is closed, the blow-by gas (11) is prevented from entering the oil discharge guide chamber (7) from the oil discharge portion (16), and the inside and outside of the breather chamber (4). When the check valve (34) is opened by the load of the separation oil (18) accumulated on the check valve (34), the separation oil (18) is discharged from the oil discharge portion (16). It may be done.
The check valve (34) is made of rubber and is provided with a slit-like valve opening (34a). When the valve shown in FIGS. 12C and 12D is closed, the check valve (34) is closed by the elastic force of the check valve (34). When (34a) is closed and the valve is opened as shown in FIG. 12 (E), the valve opening (34a) can be opened by the load of the separation oil (18).
When the second modification of the oil discharge section (16) is used, it is not necessary to provide the oil reservoir (17) of the cylinder head (1) used in the basic example or the first modification. The same applies to the third modification of the oil discharger (16) shown in FIG. 12 (F), the fourth modification shown in FIGS. 13 (A) and 13 (B), and the fifth modification shown in FIG. 13 (C). is there.

  As in the third modification shown in FIG. 12 (F), the oil discharge part (16) is provided with an orifice (35) at the lower end, and is separated while accumulating the separated oil (18) on the orifice (35). The oil (18) is allowed to gradually flow out, the orifice (35) is blocked with the separated oil (18), and the blow-by gas (11) does not enter the oil discharge guide chamber (7) through the oil discharge portion (16). There may be.

  As in the fourth modification shown in FIGS. 13A and 13B, the oil discharge portion 16 is provided with a pair of upper and lower descending baffle plates 36 projecting from the inner peripheral surface of the lower end portion. While collecting the separation oil (18) on the baffle plate (36), the separation oil (18) is gradually flowed out, the oil discharge part (16) is closed with the separation oil (18), and the oil discharge part (16) is closed. Then, the blow-by gas (11) may not enter the oil discharge guide chamber (7).

As in the fifth modification shown in FIG. 13 (C), the oil discharge part (16) is provided with a large-diameter chamber (37) at the upper end and an orifice (37a) at the upper part of the large-diameter chamber (37). The provided ceiling (37b) may be provided.
In the case of this fifth modification, normally, the separated oil (18) passes through the orifice (37a) and then flows through the large-diameter chamber (37) to the oil discharge part (16). At this time, since the separated oil (18) is accumulated in the oil discharge portion (16), it is possible to prevent a problem that the blow-by gas (11) enters the oil discharge guide chamber (7). Further, even if the oil discharge guide chamber (7) is suddenly depressurized and the separated oil (18) is sucked up from the oil discharge portion (16) into the large diameter chamber (37) and flows backward, the separated oil (18) remains in the diameter. In the process of passing through the orifice (37a) from the large space of the large chamber (37), resistance is received, and suction to the oil discharge guide chamber (7) is prevented.

As shown in FIG. 3, a partition wall (39) divides the outlet side oil separation chamber (6a) having the blow-by gas outlet (6) and the oil discharge guide chamber (7). The communication ports (40) communicate with each other, and in the outlet-side oil separation chamber (6a), oil mist contained in the blow-by gas (11) is condensed on the chamber wall to perform oil separation of the blow-by gas (11).
The outlet side oil separation chamber (6a) is formed long in the lateral direction. A third partition wall (39) that divides between the outlet side oil separation chamber (6a) and the oil discharge guide chamber (7) is formed to be long in the lateral direction, and is connected to the bottom wall (4a) of the breather chamber (4). It is integrally molded and protrudes upward from the bottom wall (4a).

The inner surface of the breather chamber (4), the upper surface of the bottom wall (4a) of the breather chamber (4), the inner peripheral surface of the groove (14) constituting the separated oil guiding path (13) , and the separated oil guiding path (13) are configured. All or part of the inner peripheral surface of the pipe (15), the inner surface of the oil discharge guide chamber (7), the oil discharge guide surface (7b), and the inner peripheral surface of the oil discharge portion (16) are as follows. Surface treatment can be performed.
An oil repellent layer such as a fluororesin is provided. In this case, the separation oil (18) quickly passes through the surface of the oil repellent layer, and the separation oil (18) is quickly discharged.
Performs embossing. In this case, the oil retention of the processed surface is enhanced, and a continuous oil film is formed by the separation oil (18) flowing through the processed surface, and the subsequent separation oil (18) smoothly passes through the surface of the oil film, so that the separated oil ( 18) is quickly discharged.
In the basic example shown in FIG. 14 (A), the cross-hatching (38) uses a cross hatching groove. The wrinkles (38) are turtle shell grooves as in the first modification shown in FIG. 14 (B), and parallel grooves along the inclination of the oil discharge guide surface (7b) as in the second modification shown in FIG. 14 (C). It may be.

(1) Cylinder head
(2) Cylinder head cover
(3) Rocker arm
(3a) Input swing end
(4) Breezer room
(4a) Bottom wall
(5) Blow-by gas inlet
(6) Blowby gas outlet
(7) Oil discharge guide chamber
(7a) Perimeter wall
(7b) Oil discharge guide surface
(9) Inlet side oil separation chamber
(10) Blowby gas bypass
(10a) Start end
(11) Blowby gas
(12) Bulkhead
(13) Separate oil guideway
(13a) Start end
(13b) Middle part
(13c) Termination
(14) Groove
(15) Pipe
(16) Oil discharge part
(17) Oil sump
(18) Separation oil
(33) Push rod

Claims (7)

Cylinder head (1), cylinder head cover (2) assembled on top of cylinder head (1), rocker arm (3) covered with cylinder head cover (2), and cylinder head cover (2) In an engine equipped with a breather chamber (4),
With the longitudinal direction of the cylinder head cover (2) as the front-rear direction, the breather chamber (4) has a blow-by gas inlet (5) at one end in the front-rear direction and a blow-by gas outlet (6) at the other end in the front-rear direction. Each with oil discharge guide chamber (7) in position,
The blow-by gas inlet (5) is opened to the bottom wall (4a) of the breather chamber (4), and the peripheral wall (7a) of the oil discharge guide chamber (7) is connected to the rocker arm (3) on the blow-by gas outlet (6) side. Projecting downward from the bottom wall (4a) of the breather chamber (4) toward the blow-by gas inlet (5) ,
The breather chamber (4) includes an oil discharge portion (16) at the lower portion of the oil discharge guide chamber (7), and the cylinder head (1) includes an oil reservoir (17), and the separated oil stored in the oil reservoir (17). (18) the oil outlet (16a) of the oil outlet (16) is immersed,
A plurality of rocker arms (3) and (3) are provided with a predetermined rocker arm (3) located on the opposite side of the blow-by gas inlet (5) with the oil discharge guide chamber (7) in between, , The peripheral wall (7a) of the oil discharge guide chamber (7) is located at the bottom wall of the breather chamber (4) to a position where it overlaps the input rocking end (3a) of the predetermined rocker arm (3). (4a) projecting downward, and the cylindrical oil discharge portion (16) is located at a position overlapping the push rod (33) of the predetermined rocker arm (3) when viewed in a direction parallel to the front-rear direction. An engine characterized by being arranged. The engine according to claim 1,
The breather chamber (4) includes an inlet-side oil separation chamber (9) having a blow-by gas inlet (5) and a blow-by gas bypass passage (10), and a blow-by gas (11) exiting the inlet-side oil separation chamber (9). ) Is introduced into the oil discharge guide chamber (7) through the blow-by gas bypass passage (10). The engine according to claim 2,
The breather chamber (4) includes a partition wall (12) that partitions the blow-by gas bypass passage (10) and the oil discharge guide chamber (7), and a separation oil guide passage (13). The separation oil guide passage (13) The portion (13a) is disposed in the inlet side oil separation chamber (9), the intermediate portion (13b) is disposed in the start end portion ( 10a) of the blow-by gas bypass passage (10), and the end portion (13c) is disposed in the partition wall (12). An engine characterized in that it passes through the lower part of the engine and is led out to the oil discharge guide chamber (7). The engine according to claim 3,
The engine characterized in that the separation oil guiding path (13) is constituted by a groove (14). The engine according to claim 3,
The engine characterized in that the separation oil guiding path (13) is constituted by a pipe (15). The engine according to any one of claims 3 to 5,
The breather chamber (4) is provided with an oil discharge portion (16) below the oil discharge guide chamber (7), and the oil discharge guide chamber (7) is provided with an oil discharge guide surface (7b) on the inner periphery. (7b) is an engine characterized in that it is inclined downward from the end portion (13c) of the separated oil guide passage (13) toward the oil discharge portion (16). The engine according to any one of claims 3 to 5,
The breather chamber (4) is provided with an oil discharge portion (16) below the oil discharge guide chamber (7), and the oil discharge guide chamber (7) is provided with an oil discharge guide surface (7b) on the inner periphery. (7b) is an engine characterized by comprising a stepped zigzag surface that descends from the terminal end (13c) of the separated oil guiding path (13) to the oil discharge part (16).

Images