JPH0248653Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) This invention relates to an engine breather device for adjusting the internal pressure of the crank chamber.

(Prior Art) Generally, in the crank chamber of a 4-stroke engine, the transmission chamber, and the valve mechanism chamber that communicate with the crank chamber, there are pressure fluctuations due to the vertical movement of the piston, and pressure fluctuations due to blow-by gas. As the temperature rises, a breather hole is provided to release the inside to the atmosphere. However, in the crank chamber, etc.
An oil pan is placed at the bottom and scatters lubricating oil, so oil particles are suspended and are easily discharged from the breather hole along with the air.
This has the disadvantage of increasing oil consumption. Therefore, a breather chamber is installed to separate the oil and return it to the crank chamber. An example is shown in FIG.

A communication hole d is provided in a partition wall c separating a crank chamber side a and a breather chamber side b, and a plate valve e is placed on the upper surface of the communication hole d. A valve holder f covers the upper side of the communication hole d, and has a communication hole g opened on one side. The plate valve e maintains the crank chamber side at a negative pressure in response to internal pressure pulsations on the crank chamber side caused by the piston, and normally does not respond almost always and no air flows out. When the internal pressure increases due to the blow-by gas filling, the plate valve e opens and air from the crank chamber side a flows into the breather chamber side b through the communication hole d. At this time, the floating oil collides with the plate valve e and the valve holder f, floats down, and passes through the through hole g to the breather chamber side b.
In this case, the expanding flow rate decreases and falls, preventing the air from blowing out to the outside.

The configuration of the plate valve e and the valve holder f has a simple structure, is easy to assemble, and is low in cost. Moreover, it is responsive and has good functionality. However, as mentioned above, the space between the plate valve e and the valve holder f becomes wet due to the floating oil, so the plate valve e sticks and becomes unable to return, resulting in a complete loss of function.
To prevent this, it is necessary to attach a return spring or use a reed valve, but due to the relationship between engine speed and natural frequency, the setting is difficult and costs increase.

(Problem to be solved by the invention) This invention was made in view of the above-mentioned problems, and is an engine that ensures the operation of a plate valve inserted in the communication hole between the crank chamber side and the breather chamber. The purpose of this invention is to provide a breather device.

[Structure of the idea]

(Means for Solving the Problems) For the above purpose, the configuration of the engine breather device according to this invention is as follows.

That is, a vertical communication hole is provided in the partition between the crank chamber or a chamber connected to the crank chamber and a breather chamber formed above, and a vertical communication hole is provided to communicate the two chambers. In an engine breather device in which a plate-shaped check valve is mounted with the upper end surface as a valve seat and a valve holder is attached that covers the outer periphery and near the upper surface of the check valve, a check valve is installed on the lower surface of the valve holder. A linear protrusion that faces closely to the upper surface of one side of the valve, and a dotted protrusion that faces the upper surface of the opposite side of the check valve and has a smaller protrusion dimension than the linear protrusion are embossed. It is formed by machining to protrude integrally.

(Function) With this structure, when the internal pressure on the crank chamber side increases, the indoor air passes through the communication hole, pushes up the plate valve, enters the valve holder, and then passes through the communication hole and enters the breather chamber. It is released into the atmosphere from the breather hole. The oil contained in the air adheres to the plate valve or valve holder and is removed, and also enters the breather chamber through the through hole, where it is depressurized and decelerated and falls, and is not discharged through the breather hole.

When the plate valve opens, its top surface touches the protrusion. Since it is a point-to-line contact, it closes immediately in response to the reduced pressure on the crank chamber side without sticking. Furthermore, due to the difference in height between the two protrusions, that is, the difference in the clearance with respect to the plate valve, the linear protrusion is used as a fulcrum to move, and the operation of the plate valve is regulated almost constant.

(Example) An embodiment of this invention is shown in FIGS. 1 and 2.

A breather chamber 3 is formed in a part of the crank chamber side 1 with a partition plate 2 interposed therebetween. A communication hole 4 is formed in the partition plate 2, and a breather hole 5 opens from the breather chamber 3 to the outside. A plate valve 6 is placed on the communication hole 4, and a valve holder 7 is formed around the outer periphery of the plate valve 6. The above configuration is the same as the conventional one.

As shown in FIG. 2, a dot-shaped projection 8 and a linear projection 9 are provided on the lower surface of the valve holder 7 to face each other and project therefrom. The protrusion 9 has a higher protrusion height than the protrusion 8.
Both protrusions 8 and 9 are embossed. Reference numeral 10 denotes a through hole that passes through the inside and outside of the valve holder 7.

With the above configuration, when the internal pressure of the spring chamber side 1 rises, indoor air passes through the communication hole 4, pushes up the plate valve 6, enters the valve holder 7, and then passes through the communication hole 10 and enters the breather chamber 3. It is released into the atmosphere from the breather hole 5. The oil contained in the air adheres to the plate valve 6 or the valve holder 7 and is removed, and is also removed from the breather chamber 3 through the through hole 10.
enters the air, depressurizes, decelerates and falls, and the breather hole 5
Do not discharge from

When the plate valve 6 is opened, its upper surface contacts the protrusions 8 and 9. Since it is a point-to-line contact, it closes immediately in response to the reduced pressure on the crank chamber side 1 without sticking. Also, due to the difference in the height of both protrusions 8 and 9, that is, the difference in clearance with the plate valve 6,
It moves with the linear protrusion 9 as a fulcrum, and the operation of the plate valve 6 is regulated almost constant.

[Effect of idea]

As described above, the engine breather device according to this invention uses a plate-shaped check valve supported by a valve holder to prevent oil from being discharged from the breather chamber. Embossed linear protrusions that face each other closely on the upper surface of one side, and dotted protrusions that face the upper surface of the check valve side on the opposite side and have a smaller protrusion dimension than the linear protrusions. This is an integrally protruding part that regulates the lift operation of the check valve and ensures return, making the function of this breather device extremely reliable. By simply providing a shaped protrusion, the original simple structure can be maintained and functionality can be improved without increasing costs.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a breather device showing an embodiment of this invention, Fig. 2 is a bottom view of the valve holder in Fig. 1, and Fig. 3 is a longitudinal sectional view of the valve holder portion of a conventional breather device. . 1... Crank chamber side, 2... Partition plate, 3... Breather chamber, 4... Communication hole, 5... Breather hole, 6...
...Plate valve, 7...Valve holder, 8, 9...Protrusion, 10...Through hole.

Claims (1)

[Scope of utility model registration request] A vertical communication hole is provided in the partition wall between the crank chamber or a chamber connected to the crank chamber and a breather chamber formed above, and the upper end surface of the communication hole is provided to communicate the two chambers. In an engine breather device, a plate-shaped check valve is mounted as a valve seat, and a valve holder that covers the outer periphery and near the top surface of the check valve is attached. By embossing, a linear protrusion that faces closely to the upper surface of one side, and a dotted protrusion that faces the upper surface of the check valve side on the opposite side and has a smaller protrusion dimension than the linear protrusion, are formed by embossing. An engine breather device characterized by being integrally formed in a protruding manner.