JPH10274024A - Engine breather device - Google Patents

Abstract

(57) [Problem] To provide a technology for effectively separating oil and preventing oil leakage in a crankcase. SOLUTION: A blow-by gas G in a crank chamber 2 is introduced into an oil separating device 10 through a gas inlet 11. The exhaust means 25 is connected to the gas outlet 15 of the oil separator 10, and the inside of the oil separator 10 and the interior of the crank chamber 2 are made negative by the forced exhaust means 25. By making the inside of the oil separating device 10 a negative pressure, pulsation inside the oil separating device 10 is eliminated, the blow-by gas G flows smoothly without going back and forth in the oil separating device 20, and oil separation by the oil separating member 23 is effectively performed. Will be Further, the inside of the crank chamber 2 also becomes a negative pressure to prevent oil leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breather device for an engine, and more particularly to a technology for more effectively separating oil by forcibly applying a negative pressure in an oil separating device.

[0002]

2. Description of the Related Art As a breather device for an engine, for example, the one shown in FIG. 7 is conventionally known. As shown in FIG. 7, the blow-by gas G in the crank chamber 2
Through the gas passage 3, the tappet cam chamber 4, the fish rod chamber 6, and the head cover 7 in order.
1, the oil mist contained in a large amount in the blow-by gas G is separated into oil in the oil separation device 100, and the separated oil is blown from the gas outlet 105 to the intake pipe 8 It is configured to recirculate inside. Note that reference numeral 102 in FIG.
Denotes a breather valve, 103 denotes steel wool as an oil separating member, and 104 denotes a gas outlet chamber.

[0003]

In the above prior art, steel wool is used as an oil separating member, but it was not always possible to effectively perform oil separation only by using the steel wool. The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a technique for more effectively performing oil separation with a simple configuration.

[0004]

The present invention is configured as follows to solve the above-mentioned problems. That is, according to the first aspect of the present invention, the blow-by gas G in the crank chamber 2 is introduced into the oil separating device 10 from the gas inlet 11 and the blow-by gas G, which has been oil-separated in the oil separating device 10, is supplied to the gas separator. In a breather device for an engine configured to be led out from the outlet 15, a forced exhaust means 25 is connected to the gas outlet 15 of the oil separating device 10.

According to a second aspect of the present invention, in the engine breather device according to the first aspect, a first oil separating device 10A in which the oil separating device 10 is provided inside the crankcase 1 and a first oil separating device 10A outside the crankcase 1 are provided. And the second oil separation device 10B provided in the first embodiment.

According to a third aspect of the present invention, in the engine breather device according to the first aspect, the exhaust means 2 is provided.
5 comprises a centrifugal fan 25b.
Are those characterized by being configured to rotate wheel 25a coaxially rotating that rotates the injection force F ₁ pumping oil of the engine.

According to a fourth aspect of the present invention, in the engine breather device of the second aspect, the exhaust means 2 is provided.
5 comprises a centrifugal fan 25b.
Is characterized in that it is configured to rotate coaxially with a rotating wheel 25a that rotates by the lift of an oil pressure pump P of the engine.

[0008]

According to the present invention, the following functions and effects are obtained. (A) In the invention described in claim 1, the oil separating device 10
The forced exhaust means 25 is connected to the gas outlet 15 of the oil separating device 1.
Since the pulsation in the oil separating device 10 can be eliminated by setting the inside of the oil separating device 10 to a negative pressure, the blow-by gas G flows smoothly without going back and forth in the oil separating device 20. Oil separation can be effectively performed. Further, the pressure in the crank chamber 2 can be reduced to a negative pressure, and oil leakage in the crankcase can be prevented.

(B) According to the invention described in claim 2, in the engine breather device described in claim 1, the first oil separation device 10A in which the oil separation device 10 is provided in the crankcase 1; With the second oil separating device 10B provided outside the case 1, the oil mist in the blow-by gas G is primarily separated by the first oil separating device 10A provided inside the crankcase 1, and the crankcase The oil mist is secondarily separated by the second oil separation device 10B provided outside the first oil separation device. Thereby, oil separation is performed more effectively.

(C) According to the third and fourth aspects of the invention, in the breather device for the engine according to the second aspect, since the exhaust means 25 is constituted by the centrifugal fan 25b, only a small amount of The oil mist remaining in the blow-by gas is blown by the centrifugal fan 25b, so that the oil separation in the blow-by gas G can be more effectively promoted.

[0011]

Embodiments of the present invention will be described below in more detail with reference to the drawings. FIG. 1 is a longitudinal sectional view of a vertical diesel engine according to a first embodiment of the present invention. The breather device of the engine E is configured such that an oil separating device 10 is fixed to the outer wall surface of the crankcase 1 and a forced exhaust means 25 communicates with a gas outlet 15 of the oil separating device 10. Also, the oil separating device 10
Communicates with the crank chamber 2 through a communication hole 21 and an oil return hole 22 opened in the crankcase 1. In addition,
As the exhaust unit 25, a feed pump or the like is used.

The oil separating device 10 accommodates, for example, steel wool 23 as an oil separating member.
Since the pulsation in the inside can be eliminated by making the inside of the oil separator 0 a negative pressure, the blow-by gas G flows smoothly without going back and forth in the oil separating device 20. The oil separation is performed more effectively, and then the blow-by gas G is returned to the intake pipe 8 of the engine E through the intake communication pipe 26.

FIG. 2 is a longitudinal sectional view of a vertical diesel engine according to a second embodiment of the present invention. The breather device includes a bubble generating type first oil separating device 10A integrally provided in a crankcase 1 and a crankcase 1
A second oil separator 10B fixed outside, a gas inlet pipe 12 forming a gas inlet 11, and an exhaust means 2 connected to a gas outlet 15 of the second oil separator 10B.
And 5.

The above-mentioned first oil separation device 1 of the bubble generation type
0A is configured to open its lower wall and introduce the lubricating oil O in the oil pan 5 into the oil separating device 10A. The gas introduction pipe 12 constituting the gas introduction port 11 is formed in a substantially U-shape, with one end facing the crank chamber 2 and the other end facing the oil separation device 1.
The lubricating oil O penetrates the side wall 10a of the OA, and penetrates into the lubricating oil O inside and is fixed to the side wall 10a.

At the other end of the gas introducing pipe 12, a bubble generating means 13 is attached so as to show a main part A in an enlarged manner. As the bubble generating means 13, a mesh member having a small mesh or a porous member is suitable because the smaller the generated bubbles, the higher the oil separating effect. On the other hand,
The second oil separation device 10B has the same configuration as the oil separation device 10 of FIG. 1, and is connected to the first oil separation device 10A via a communication hole 21 and an oil return hole 22 opened in the crankcase 1. It communicates with the pressure separation chamber 14.

By evacuating the second oil separator 10B by the exhaust means 25, the first oil separator 1
The negative pressure of the negative pressure separation chamber 14 becomes 0 A.
The oil level S ₃ in the cylinder 4 rises, and the initial oil level S ₁ in the crank chamber 2 drops to the oil level S ₂ . Thereby, the crankcase 2
The blow-by gas G inside is introduced into the first oil separation device 10A through the gas introduction pipe 12 constituting the gas introduction port 11, becomes bubble-like through the bubble generation means 13, and is stored inside. In the lubricating oil O. At this time, the oil mist contained in the blow-by gas G
Since the specific gravity is higher than that of air, the oil film of the oil collects in the lower half of the bubbles, and the oil film is absorbed by the lubricating oil O. Thereby, the primary oil in the blow-by gas G is effectively separated. Next, the second oil separation device 10B
The secondary oil separation is completely performed by the oil separation member 23 housed in the inside.

[0017] Note that by sufficiently reducing the pressure receiving area of the first oil separator 10A against the pressure receiving area of the lubricating oil O in the crank chamber 2, the initial oil level S ₁ of the crank chamber 2 oil even slight amount to decrease the surface S _2, oil level S ₃ in the oil separator 10A is increased to sufficient height h required for oil separation. Therefore, even when the engine E mounted on the work machine or the like is inclined, there is no possibility that the oil separating function is lost. At this time, the pressure difference between the inside of the crank chamber 2 and the inside of the negative pressure separation chamber 14 corresponds to the above h, but this pressure difference h can be sufficiently achieved by a pump having a small suction force. Further, by letting the blow-by gas G pass through the lubricating oil O through the gas introduction pipe 12, the pressure inside the crank chamber 2 can be reduced to a negative pressure, and oil leakage in the crankcase can be prevented.

FIG. 3 is a longitudinal sectional view of a main part of an engine according to a third embodiment of the present invention. This breather device is configured similarly to the breather device of FIG. 2 in that it has an air bubble generating type oil separation device 10 provided integrally within the crankcase 1, but instead of the exhaust means 25, a centrifuge is used. The configuration differs from the breather device of FIG. 2 in that a fan 25b is used. The centrifugal fan 25b is configured to rotate coaxially with the rotary wheel 25a. The rotary wheel 25a opens the lubricating oil injection port 17 in the crankcase ₁ and rotates with the injection force F1 of the pumping oil. The above oil separation device 1
The blow-by gas G primary separated at 0 is drawn into the centrifugal fan 25b through the communication passage 16. The oil mist slightly remaining in the blow-by gas G is beaten by the centrifugal fan 25b, so that the oil separation can be more effectively achieved.

FIG. 4 is a longitudinal sectional view of a main part of an engine according to a fourth embodiment of the present invention. This breather device is configured similarly to the breather device of FIG. 3 in that the breather device includes an oil separating device 10 of a bubble generation type provided integrally in the crankcase 1, a rotating wheel 25a, and a centrifugal fan 25b. The configuration of the rotating wheel 25a is different from that of the breather device of FIG. 3 in that the rotating wheel 25a is configured to rotate by the lift of the oil pressure pump P.

FIG. 5 is a longitudinal sectional view of a main part of an engine according to a fifth embodiment of the present invention. This breather device is shown in FIG.
The second oil separator 10B is different from the second embodiment (FIG. 2) in that the second oil separator 10B is omitted and another bubble generating type oil separator 10 is provided outside the crankcase 1. The principle of 10 is the first oil separation device 1 in FIG.
It is configured similarly to 0A. That is, in this breather device, the oil separating device 10 provided outside the crankcase 1 and the oil pan 5 communicate with each other via the oil return pipe 17, and one end of the gas introduction pipe 12 constituting the gas introduction port 11 is connected to the crank chamber 2. And the other end communicates with the oil return pipe 17 via a pipe joint 19, and the exhaust means 25 communicates with the gas outlet 15 of the oil separator 10.

According to the above configuration, the oil separating device 10 is exhausted by the exhaust means 25, so that the negative pressure separating chamber 14 in the oil separating device 10 has a negative pressure. surface S ₃ is increased, decreased initial oil level S ₁ of the crank chamber 2 until the oil surface S _2. As a result, the blow-by gas G in the crank chamber 2 is introduced into the oil separation device 10 through the gas introduction pipe 12 and the oil return pipe 17, and is bubbled through the bubble generation means (not shown). It floats in the stored lubricating oil O. At this time, the oil mist contained in the blow-by gas G is absorbed by the lubricating oil O, and the oil is effectively separated. In addition, since the case main body 10a and the oil return pipe 17 of the oil separating device 10 are made of a transparent member, the state of oil separation and the state of consumption of lubricating oil can be visually recognized, which is convenient.

FIG. 6 is a longitudinal sectional view of an essential part of an engine according to a sixth embodiment of the present invention. This breather device is a modified example of FIG. 5, and differs from FIG. 5 in that the gas introduction pipe 12 and the oil return pipe 17 are provided independently of each other, and the other points are configured similarly to FIG. That is, one end side of the gas introduction pipe 12 formed in a substantially U shape faces the crank chamber 2,
The other end side communicates with the lower part of the oil separation device 10,
One end of the oil return pipe 17 communicates with the main body side wall 10 a of the oil separating device 10, and the other end communicates with the oil pan 5. According to this embodiment, even if the oil level of the lubricating oil O in the oil pan 5 decreases due to the consumption of the lubricating oil, a constant amount of oil is always maintained in the oil separating device 10. The oil separating function is ensured irrespective of the position of the oil level inside.

In the present invention, as long as the exhaust means is connected to the gas outlet of the oil separating device, it does not matter whether the oil separating device is of the bubble generating type.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a vertical diesel engine according to a first embodiment of the present invention.

FIG. 2 is a diagram corresponding to FIG. 1 according to a second embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a main part of an engine according to a third embodiment of the present invention.

FIG. 4 is a diagram corresponding to FIG. 3 according to a fourth embodiment of the present invention.

FIG. 5 is a diagram corresponding to FIG. 3 according to a fifth embodiment of the present invention.

FIG. 6 is a diagram corresponding to FIG. 3 according to a sixth embodiment of the present invention.

FIG. 7 is a diagram corresponding to FIG. 1 according to a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Crankcase, 2 ... Crank chamber, 5 ... Oil pan, 10 ... Oil separator, 10A ... First oil separator, 10B ... Second oil separator, 11 ... Gas inlet, 12 ... Gas inlet pipe , 15 ... gas outlet, 25 ... exhaust means, 25a ... rotating wheel, 25b ... centrifugal fan, E ... engine, F ₁ ... jet force of pumping oil, G ... blowby gas, P ... oil pressure pump, O ... lubricating oil .

Claims (4)

[Claims] A blow-by gas (G) in a crank chamber (2) is supplied to an oil separation device (1) through a gas inlet (11).
0), and the blow-by gas (G) oil-separated in the oil separation device (10) is supplied to the gas outlet (15).
A breather device for an engine, wherein the exhaust device (25) communicates with a gas outlet (15) of the oil separating device (10). . 2. A breather device for an engine according to claim 1, wherein said oil separating device (10) is provided in a crankcase (1), a first oil separating device (10A), and a crankcase (1). A second oil separation device (10
B), and a breather device for an engine. 3. The breather device for an engine according to claim 1, wherein the oil separating device (10) is provided in a crankcase (1), and the exhaust means (25) comprises a centrifugal fan (25b); The centrifugal fan (25b) is configured to rotate coaxially with a rotating wheel (25a) that rotates by the injection force (F ₁ ) of the pumping oil of the engine. 4. The breather device for an engine according to claim 1, wherein the oil separating device (10) is provided in a crankcase (1), and the exhaust means (25) is constituted by a centrifugal fan (25b); The breather device for an engine, wherein the centrifugal fan (25b) is configured to rotate coaxially with a rotating wheel (25a) that rotates by the lift of an oil pressure pump (P) of the engine.