JP2002235521A - Breather chamber of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in a conventional breather chamber wherein an oil trap material is provided only in one place to make oil removing capacity insufficient, and an individual member or the like for holding the oil trap material must be mounted for solving the problem, thereby increasing cost. SOLUTION: In the breather chamber 55 of an engine that is constituted in a rocker arm chamber and passes blow-by gas, a shielding plate 57 as a lid body mounted to a rocker arm case 52 constituting the breather chamber 55 is provided with a plurality of holding parts 57a for holding the oil trap material 59 for trapping oil mist in the blow-by gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breather chamber provided in a valve arm chamber of an engine.

[0002]

2. Description of the Related Art Conventionally, in an engine, a breather chamber is provided in a valve arm case that covers an upper part of a cylinder head, and the blower chamber separates blow-by gas containing oil mist into a gas component and an oil component. It is composed. Further, a fuel injection valve is provided in the valve arm case. The breather chamber is formed of a space surrounded by a side wall of the valve arm case, a rib protruding from the rear surface of the valve arm case, and a bottom plate provided at a predetermined interval from the rear surface of the valve arm case.

[0003] The breather chamber collects an oil component by adhering oil mist to the wall surface of the breather chamber through which the blow-by gas passes. It was configured to capture the oil content in the blow-by gas.

[0004]

As described above, in a breather chamber configured to remove oil mist by capturing with an oil trap material, the oil trap material is provided only at one location of the breather chamber. In addition, when the oil removing ability is not sufficient and the engine is in the inclined position, the blow-by gas inlet of the oil trap material may be blocked by the oil, and the oil separating function may not be able to be exhibited. In order to solve this problem, if a plurality of oil trap members are provided, members for holding the oil trap members must be separately attached, which increases the cost. Further, the fuel injection valve provided in the valve arm case is fixed to the cylinder head by being pressed by the fuel injection valve retainer. However, the use of the fuel injection valve retainer increases the number of parts and increases the height. This not only reduced costs but also occupied the space inside the valve arm case.

[0005]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. That is, in the breather chamber of the engine which is formed in the valve arm chamber and through which the blow-by gas passes, the oil trapping the oil mist in the blow-by gas is attached to the lid attached to the valve arm case which forms the breather chamber. A holding part for holding the trap material,
Multiple formed.

According to a second aspect of the present invention, in a breather chamber of an engine, which is formed in a valve arm chamber and through which blow-by gas passes, a cover attached to the valve arm case, which constitutes the breather chamber, is provided in the valve arm case. A fuel injection valve presser for pressing a fuel injection valve housed in the fuel injection valve is formed.

According to a third aspect of the present invention, the breather chamber is applied to a four-valve engine in which two intake valves and two exhaust valves are provided.

[0008]

Next, an embodiment of the present invention will be described. FIG. 1 is a front sectional view showing a valve arm chamber in which the breather chamber of the present invention is formed, FIG. 2 is a plan sectional view thereof, FIG. 3 is a rear view showing a fuel injection valve press formed on a shielding plate of the breather chamber, FIG. 4 is a front cross-sectional view, FIG. 5 is a rear view showing a second embodiment of the breather chamber, FIG. 6 is a rear view showing a shield plate of the breather chamber, and FIG. 7 is a side cross-sectional view showing the breather chamber. 8 is a front sectional view showing the breather chamber.

First, the valve arm chamber constituting the breather chamber of the present invention will be described. As shown in FIGS. 1 and 2, a valve arm case 2 is disposed above a cylinder head 1 of an engine, and a valve arm chamber 5 is formed. The valve arm case 2 is formed by being divided into an upper valve arm case 2b and a lower valve arm case 2a.

The engine according to the present embodiment is constituted, for example, by three cylinders, and has two intake valves 16a.
The engine is a so-called four-valve engine provided with an exhaust valve 16a and two exhaust valves 16b. The engine is of an OHV type, and the intake valves 16a and 16
a, the upper ends of the two exhaust valves 16b, 16b, the upper end of the push rod 13, the valve arm 14, the fuel injection valve 17, and the like. The valve arm 14 is swingably supported by a valve arm shaft 11 provided in the valve arm chamber 5.

One valve arm 14 is provided for each of the intake valves 16a and 16a and each of the exhaust valves 16b and 16b. The valve arm 14 swings by a push rod 13 that slides up and down, and the intake valves 16a and 16a , And the exhaust valves 16b, 16b are opened and closed, respectively.

A fuel injection valve 17 is disposed substantially at the center of the arrangement of the intake valves 16a and 16a and the exhaust valves 16b and 16b in plan view.

The fuel injection valve 17 is connected to a fuel pipe 21 which enters the valve arm chamber 5 from the outside, and is supplied with high-pressure fuel. The fuel pipe 21 includes an internal pipe 21 a provided inside the valve arm chamber 5 and an external pipe 21 b provided outside the valve arm chamber 5, and includes the internal pipe 21 a and the external pipe 21.
b is a side surface portion of the lower valve arm case 2a, and is connected by a high-pressure seal member 22.

The fuel injection valve 17 of each cylinder is connected to the fuel return pipe 2
3 are connected to each other, so that excess fuel oil is returned from the fuel return port 24 to the fuel tank through the fuel return pipe 23.

A plurality of valve arm shaft support members 7 are fixedly provided on the upper surface of the cylinder head 1 in the valve arm chamber 5, and the valve arm shaft 11 is provided with the valve arm shaft support member 7 and the lower valve arm case. 2
a. A bolt member 31 is screwed into the valve arm shaft support member 7 from above, and an upper portion of the bolt member 31 projects above the valve arm shaft support member 7. The valve arm shaft support member 7 is disposed, for example, between each cylinder. The upper valve arm case 2b has a fixing hole 2c at a position corresponding to the position where the valve arm shaft support member 7 is disposed.
A fixing nut 32 is inserted into the fixing hole 2c from above the upper valve arm case 2b. The fixing nut 32 is screwed onto an upper portion of the bolt member 31.

When the fixing nut 32 screwed into the bolt member 31 is tightened, the flange portion 32a of the fixing nut 32 which is engaged with the peripheral portion of the fixing hole 2c moves the upper valve arm case 2b downward. Accordingly, the lower valve arm case 2a disposed below the upper valve arm case 2b and the upper valve arm case 2b is fixed to the cylinder head 1. That is, by fastening the fixing nut 32 to the bolt member 31 that is screwed into the valve arm shaft support member 7, the upper valve arm case 2 pressed downward by the fixing nut 32.
The lower valve arm case 2a is attached and fixed to the cylinder head 1 via b. A gasket 55 is interposed between the cylinder head 1 and the lower valve arm case 2a to seal the joint surface between them.

As shown in FIGS. 3 and 4, a breather chamber 36 is formed in the upper valve arm case 2b. The breather chamber 36 fills a space surrounded by a ceiling surface in the upper valve arm case 2b and a rib 2c projecting downward from the ceiling surface in the upper valve arm case 2b.
It is closed by a shielding plate 37 attached to the lower end of the. That is, the shielding plate 37 is a lid constituting the breather chamber 36.

In the breather chamber 36, gas inlets 36a and 35a are formed by opening both ends in the longitudinal direction, and blow-by gas in the valve arm chamber 5 is discharged from the gas inlets 36a and 35a. It enters the chamber 36. The blow-by gas that has entered the breather chamber 36 passes through the gas passage in the breather chamber 36 and is
The oil is removed by colliding with the ceiling surface of b or the wall surface of the rib 2c. The blow-by gas from which the oil has been removed is guided to the intake side through the gas outlet 36b.

The breather chamber 36 is formed at one end in the short direction of the upper valve arm case 2b. From the inner end of the shielding plate 37, a fuel injection valve holder 37a is moved substantially inward in the horizontal direction. It is protruding. The shielding plate 37 and the fuel injection valve press 37a are integrally formed by a sheet metal member or the like, and the fuel injection valve press 37a is bent upward at both ends to form reinforcing portions 37b. The strength is improved. Also, the fuel injection valve presser 37a is formed by the number of cylinders, and the upper valve arm case 2b is
When the fuel injection valve 17 is mounted, the respective fuel injection valve pressers 37a are positioned above the respective fuel injection valves 17 and are configured to press the fuel injection valves 17 from above. As a result, the fuel injection valve 17 is attached and fixed to the cylinder head 1.

As described above, the breather chamber 36 is constituted.
By integrally forming the fuel injection valve press 37a for pressing the fuel injection valve 17 on the shielding plate 37 attached to the upper valve arm case 2, the fuel injection valve press is separately provided in the valve arm chamber 5. This eliminates the need to provide them, thereby reducing the number of parts and reducing the cost, and does not squeeze the space in the valve arm chamber 5. In particular, in the case of this example, the fuel injection valve presser 37
Since a is formed by a plate-shaped member, it can greatly contribute to space saving in the valve arm chamber 5. Furthermore, since the fuel injection valve presser 37a of this example is applied to a so-called four-valve engine in which the entire fuel injection valve 17 is housed in the valve arm chamber 5, the number of parts is reduced, the cost is reduced, and the valve is reduced. Arm chamber 5
The effect of space saving inside can be remarkably exhibited. In this example, the valve arm case 2 is described as being divided into a lower valve arm case 2a and an upper valve arm case 2b. However, the present invention is not limited to the valve arm case having a split structure. Is applicable to a valve arm case formed integrally.

Next, an example in which an oil trap material for capturing oil mist in blow-by gas is provided on the shield plate 37 will be described.

That is, in the valve arm case 52 shown in FIG. 11, the space surrounded by the rib 52a is a breather chamber 55.
The lower end of the breather chamber 55 is closed by a shielding plate 57 shown in FIG. Holding members 57 a and 57 projecting downward are provided on the lower surface of the shielding plate 57.
a are attached to both ends in the longitudinal direction.

As shown in FIGS. 13 and 4, the holding member 57a is formed by bending the left and right ends and the lower end of a thin plate member in the same direction. A net-shaped oil trap member 59 made of steel wool or the like is held in a space surrounded by the side wall of the oil trap member.

The blow-by gas in the valve arm case 52 is supplied to the holding member 57a from both corners at the lower end of the holding member 57a.
a, and enters the breather chamber 55 through the oil trap member 59. Blow-by gas is the holding member 5
When passing through the oil trap member 59 in 7a, the oil mist in the blow-by gas is captured by the oil trap member 59, and the oil component is removed.

The blow-by gas that has entered the breather chamber 55 is guided through the breather chamber 55 from the outlet passage 52b to the intake side of the engine through a path indicated by an arrow in FIG. The passage in the breather chamber 55 through which the blow-by gas passes is formed in a maze shape by a plurality of ribs 52c, and while passing through the breather chamber 55, the oil mist in the blow-by gas is breathed. The gas adheres to the wall surface of the chamber 55 and is removed from the blow-by gas.

As described above, in the present embodiment, the holding member 5
Captured by an oil trap member 59 in 7a,
When passing through the breather chamber 55, the oil mist in the blow-by gas is removed as described above to improve the oil separation function.

Here, when the blow-by gas is guided into the breather chamber 55 from the lower end of the holding member 57a projecting downward (ie, the lower end of the valve arm case 52), for example, when the engine is in an inclined position. , Valve arm case 5
The lower end of the holding member 57a disposed at the end of the shielding plate 57 is immersed in the oil accumulated at the bottom of the inside 2 so that the blow-by gas inlet is blocked and the oil separating function cannot be exhibited. However, in this example, since the holding members 57a are attached to both ends in the longitudinal direction of the shielding plate 57, even if the entrance of one of the holding members 57a is closed, the blow-by gas is sucked from the other entrance. Therefore, even in such a case, the oil separating function can be maintained. Further, since the holding member 57a is formed integrally with the shielding plate 57 by a sheet metal member or the like, there is no need to provide a separate holding member, the number of components can be reduced, and the cost can be reduced. The function of separating oil mist from blow-by gas can be improved with a simple and low-cost configuration. Furthermore, by providing a plurality of holding members 57a, the efficiency of capturing the oil mist is higher than in the case where only one holding member 57a is provided, and the oil separation function can be improved.

[0028]

As described above, the present invention has the following advantages. That is, as described in claim 1, a plurality of holding portions for holding an oil trap material for catching oil mist in blow-by gas are formed on the lid attached to the valve arm case constituting the breather chamber. The number of parts can be reduced, and the function of separating oil mist from blow-by gas can be improved with a simple and low-cost configuration. Further, for example, even when the engine is in an inclined position, all the inlets for blow-by gas are not blocked by the oil accumulated at the bottom in the valve arm case, and the oil separating function can be maintained. . Further, by providing a plurality of holding members, the efficiency of capturing the oil mist is increased as compared with the case where only one holding member is provided, and the oil separating function can be improved.

Furthermore, in the breather chamber of the engine, which is formed in the valve arm chamber and through which blow-by gas passes, the cover attached to the valve arm case, which constitutes the breather chamber, is provided with a valve arm case. Since the fuel injection valve presser for pressing the fuel injection valve housed inside is formed, there is no need to separately provide the fuel injection valve presser in the valve arm chamber, and the number of parts and the cost are reduced. There is no pressure on the space inside the arm compartment. In particular, by forming the fuel injection valve retainer with a plate-shaped member, it can greatly contribute to space saving in the valve arm chamber.

Further, since the breather chamber is applied to a four-valve engine in which two intake valves and two exhaust valves are provided, a four-valve engine in which the entire fuel injection valve is housed. The effect of reducing the number of parts, reducing cost, and saving space in the valve arm chamber of the engine can be remarkably exhibited.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a valve arm chamber in which a breather chamber of the present invention is formed.

FIG. 2 is a plan sectional view of the same.

FIG. 3 is a rear view showing a fuel injection valve retainer formed on a shielding plate of a breather chamber.

FIG. 4 is a front sectional view of the same.

FIG. 5 is a rear view showing a second embodiment of the breather chamber.

FIG. 6 is a rear view showing a shielding plate of the breather chamber.

FIG. 7 is a side sectional view showing the breather chamber.

FIG. 8 is a front sectional view showing the breather chamber.

[Explanation of symbols]

 2 Valve Arm Case 2b Upper Valve Arm Case 2c Rib 5 Valve Arm Chamber 17 Fuel Injection Valve 36 Breather Chamber 37 Shielding Plate 37a Fuel Injection Valve Holder

[Procedure amendment]

[Submission date] February 9, 2001 (2001.2.9)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (4)

[Claims] An oil trap material for catching oil mist in blow-by gas is provided on a lid attached to a valve arm case constituting a breather chamber in a breather chamber of an engine formed in a valve arm chamber and through which blow-by gas passes. A breather chamber for an engine, wherein a plurality of holding portions for holding are formed. In a breather chamber of an engine, which is formed in a valve arm chamber and through which blow-by gas passes, a fuel injection housed in the valve arm case is provided on a lid attached to the valve arm case, which constitutes the breather chamber. A breather chamber for an engine, wherein a fuel injection valve presser for pressing a valve is formed. 3. The breather chamber of an engine according to claim 2, wherein the breather chamber is applied to a four-valve engine in which two intake valves and two exhaust valves are provided. (4)