JPH07269326A - Oil separator for blowby gas of engine - Google Patents

Abstract

PURPOSE:To prevent the generation of corrosion of each lubricated part caused by oil within a crankcase as well as an occurrence of corrosion in a sliding/ touching part between a cylinder and a piston by avoiding a birth of emulsion sludge in an oil separator for blowby gas in an engine. CONSTITUTION:Outside air is made pass through both an air cleaner 15 and an air intake passage 14 in order to be introduced into an engine 1. An oil separator 29, which intakes blowby gas 24 produced by the engine 1 in order to separate the oil contained by the blowby gas 24, is prepared separate from the engine 1. The blowby gas, whose oil content was separated by the oil separator 29, is introduced into the air intake passage 14. An oil return passage 43 is prepared, which returns the oil separated by the oil separator 29 to an oil pan 22 within a crankcase 2 of the engine 1. In addition, a heater 44 for heating up the oil separator 29 is prepared.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil separation device for separating oil from blow-by gas generated in an engine for a gas heat pump, which is an air conditioner, for example.

[0002]

2. Description of the Related Art Conventionally, for example, FIG.
There is one configured as shown by 1.

Referring to the drawings, reference numeral 1 is a four-cycle engine. The engine 1 has a crankcase 2, a crankshaft 3, a cylinder 4 and a piston 5, and the crankshaft 3 and the piston 5 are connected to each other. They are connected by a rod 6. A cylinder head 7 is mounted on the cylinder 4, and a space surrounded by the piston 5 and the cylinder head 7 in the cylinder 4 serves as a combustion chamber 9.

The cylinder head 7 has an intake port 10
And an exhaust port 11 are formed, and these can be opened and closed by a valve (not shown). The valves are appropriately opened and closed by a valve mechanism (not shown) provided on the cylinder head 7. A cylinder head cover 12 that covers this valve mechanism is provided.

Intake passage 14 connected to the intake port 10
Is provided, and an air cleaner 15 is provided at the upstream end of the intake passage 14. The air cleaner 15 is composed of a cleaner case 16 and an element 19 for partitioning an inlet 17 and an outlet 18 formed in the cleaner case 16, and the outlet 18 is formed in the bottom portion of the cleaner case 16 and is provided in the intake passage 14. It communicates with the upstream end. A throttle 20 is provided in the middle of the intake passage 14.

An oil pan 22, which is an oil reservoir, is provided at the bottom of the crankcase 2. Lubricating oil 23 is stored in the oil pan 22, and the lubricating oil 23 lubricates each portion of the engine 1 such as a sliding contact portion between the cylinder 4 and the piston 5.

The operation of the engine 1 is the same as the conventional one. At this time, the outside air is taken in through the inlet 17 of the cleaner case 16 and filtered through the element 19 (arrow A in the figure). It is taken into the combustion chamber 9 together with the fuel through the intake passage 14 (arrow B in the figure), and is burned there. Then, the combustion gas is exhausted through the exhaust port 11 (arrow C in the figure).

During operation of the engine 1, the cylinder 4
The blow-by gas 24 flows from the combustion chamber 9 side into the crankcase 2 through the sliding contact portion between the piston 5 and the piston 5 (arrow D in the figure). Therefore, a recovery device 25 for recovering the blow-by gas 24 is provided.

The recovery device 25 is the crankcase 2
Labyrinth 27 communicating with the inside of this and this labyrinth 2
Recovery passage 28 from 7 to the inside of the cleaner case 16
have. In the air cleaner 15, an oil separator 29 is provided separately from the engine 1, and the oil separator 29 is composed of an element 30. The blow-by gas 24 in the crankcase 2 passes through the labyrinth 27 and the recovery passage 28 and is sucked into the cleaner case 16 (arrow E in the figure).

In this case, as for the oil contained in the blow-by gas 24, the oil contained in the blow-by gas 24 is the element 30.
Are separated as they pass through. Then, the blow-by gas 24 after the oil is separated in this way is sucked into the intake passage 14 together with the outside air (arrow F in the figure), and is introduced into the combustion chamber 9 where it is burned. Further, the oil separated by the element 30 also flows down along the inner surface of the intake passage 14 and is sent to the combustion chamber 9 where it is again lubricated or burned.

[0011]

[SUMMARY OF THE INVENTION Incidentally, in the above conventional configuration, when the engine 1 is long-term operation, especially in high load region, NO _x occurs mostly an acidic gases during combustion. Further, the blow-by gas 24 contains water vapor.

On the other hand, as described above, the oil separator 29 is provided separately from the engine 1 and is not easily heated by the engine 1, so the temperature tends to be low. Therefore, when the blow-by gas 24 is sent to the oil separator 29 as described above, the blow-by gas 24
The water vapor therein easily condenses into condensed water, and the acidic gas dissolves in the condensed water to become strongly acidic.

Since the condensed water mixes with the oil separated here in the oil separator 29, strong acidic emulsion sludge is generated, and the emulsion sludge passes through the intake passage 14 and the combustion chamber 9 together with the intake air.
There is a problem that the sliding contact portion between the cylinder 4 and the piston 5 is corroded due to the acidity of the emulsion sludge that is sucked into the inside.

Further, a part of the emulsion sludge passes through the sliding contact portion together with the blow-by gas 24 and is returned to the oil pan 22 which is an oil storage portion below the crankcase 2. Also becomes acidic. Therefore, when the lubricating parts are lubricated by the oil in the oil pan 22, there is a problem that the lubricating parts are corroded.

Further, as described above, when the emulsion sludge is sucked into the combustion chamber 9, it adheres to the spark plug and leaks it, thereby causing a problem that the engine performance is deteriorated.

[0016]

SUMMARY OF THE INVENTION The present invention has been made by paying attention to the above-mentioned circumstances, and prevents emulsion sludge from being generated in an oil separation device for blow-by gas of an engine.
In addition to corrosion of the sliding contact part between the cylinder and piston, prevent oil from corroding the lubricating parts by the oil in the oil storage part in the crankcase, and maintaining good engine performance. Even in such a case, it is an object of the present invention to simplify the configuration of the oil separation device.

[0017]

[Means for Solving the Problems] The present invention for achieving the above object is as follows.

According to a first aspect of the present invention, in an oil separation device for blow-by gas of an engine, an air cleaner is communicated with the engine through an intake passage, and external air is introduced into the engine through the air cleaner and the intake passage in order. On the other hand, on the other hand, an oil separator for inhaling the blow-by gas generated from this engine and separating the oil contained in this blow-by gas is provided separately from the engine, and after the oil is separated by the oil separator. When blow-by gas is introduced into the intake passage, an oil return passage for returning the oil separated by the oil separator to the oil storage portion in the crankcase of the engine is provided, and the oil separator is A heater for heating is provided.

According to a second aspect of the present invention, in the first aspect, an engine room for accommodating the engine is provided, and a room temperature sensor for detecting the temperature in the engine room is provided.
When the temperature inside the engine room is lower than a predetermined temperature by the detection signal of the room temperature sensor, the heater is made to function.

According to a third aspect of the present invention, in the first aspect of the present invention, a temperature sensor for detecting the temperature of the oil separator is provided, and when the temperature of the oil separator is lower than a predetermined temperature by the detection signal of the temperature sensor. The heater is made to function.

[0021]

[Operation] The operation according to the invention of claim 1 is as follows.

That is, if the oil separator 29 is provided separately from the engine 1, the oil separator 29 is less likely to be heated by the engine 1, and the temperature tends to be low. Therefore, when the blow-by gas 24 is sent to the oil separator 29, the water vapor in the blow-by gas 24 is condensed to generate condensed water, and the acidic gas generated by the combustion of the engine 1 is dissolved in the condensed water, so that the acidity is strong. Will be things.

Since this condensed water mixes with the oil separated here in the oil separator 29, strong acidic emulsion sludge is generated thereby, and the sliding contact portion between the cylinder 4 and the piston 5 is corroded. It causes various inconveniences.

Therefore, in the present invention, the oil separator 29 described above is used.
Oil return passage 43 for returning the oil separated in step 2 into the oil pan (oil storage part) 22 in the crankcase 2 of the engine 1
Is provided.

Therefore, the oil separated by the oil separator 29 passes through the oil return passage 43 without passing through the sliding contact portion between the cylinder 4 and the piston 5 from the oil separator 29 side, and is more directly fed. Therefore, the oil is returned to the oil pan (oil storage portion) 22.

Therefore, it is possible to prevent the oil from passing through the sliding contact portion between the cylinder 4 and the piston 5 toward the oil pan (oil storage portion) 22 side.

Further, a heater 44 for heating the oil separator 29 is provided.

Therefore, the oil separator 29 is heated by the heater 44 and kept at a high temperature to some extent. Therefore, when the blow-by gas 24 is sent to the oil separator 29, it is included in the blow-by gas 24. While the oil is separated, the steam in the blow-by gas 24 is prevented from becoming condensed water, and the steam passes through the oil separator 29 as a gas.

Therefore, the dew condensation water is prevented from being mixed with the oil separated by the oil separator 29, and the generation of emulsion sludge is prevented.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described below with reference to the drawings.

Incidentally, the constructions of these embodiments that are common to the above-mentioned conventional construction shown in FIG. 11 are designated by the reference numerals in the drawing, and the explanation thereof is omitted.

(First embodiment)

1 to 4 show a first embodiment.

In FIG. 2, the oil separator 29 has a sheet metal casing 31 that covers the element 30, and a suction port 32 for introducing the blow-by gas 24 is formed in the lower portion of the casing 31. Is connected to the downstream end of the recovery passage 28 formed by the flexible tube 33. On the other hand, an exhaust port 34 for exhausting the blow-by gas 24 from the casing 31 is formed in the upper part of the casing 31, and the exhaust port 34 is provided in the intake passage 14 downstream of the air cleaner 15 and upstream of the throttle 20. The flexible tube 35 communicates with each other.

Therefore, when the engine 1 is operating, the outside air sucked through the air cleaner 15 is prevented from directly contacting the oil separator 29. Therefore, the oil separator 29
The generation of dew condensation water is prevented, that is, the dew condensation water mixes with the oil separated by the oil separator 29, thereby avoiding the disadvantage that emulsion sludge is generated.

The oil separator 29 will be described in more detail.

In FIG. 2, the element 30 is interposed between the suction port 32 and the discharge port 34, and a baffle plate 37 having a large number of holes 36 is provided between the suction port 32 and the element 30. Provided, also
Another baffle plate 38 having the same configuration as the baffle plate 37 is provided so as to cover the element 30 from below.

When the blow-by gas 24 is sucked into the casing 31 through the suction port 32 as shown by an arrow E in each figure, first, the blow-by gas 24 is sucked.
It passes through each hole 36 while colliding with 7, 38. On this occasion,
The oil contained in the blow-by gas 24 loses its inertial force, flows down to the bottom of the casing 31, and is stored there.

The element 30 allows air and water vapor in the blow-by gas 24 to pass therethrough, while adsorbing oil in the blow-by gas 24 and casing 3
The blow-by gas 24 after being made to flow down to the bottom portion of the No. 1 and separated from the oil is sucked into the intake passage 14 through the discharge port 34 and the tube 35 as shown by an arrow F in each figure. Then, the oil stored as described above is returned to the oil pan 22 which is an oil storage portion in the crankcase 2 through the recovery passage 28 (arrow G in FIG. 2). That is, the recovery passage 2
Reference numeral 8 also serves as an oil return passage 43 for returning the oil into the oil pan 22.

As shown by the phantom line in FIG. 2, an oil return passage 43 extending from the bottom of the casing 31 of the oil separator 29 into the oil pan 22 is separately provided, and as shown by an arrow I in the drawings, the casing The oil accumulated at the bottom of 31 may be returned into the oil pan 22 without being affected by the blow-by gas 24.

In FIG. 1, the oil separator 29 has a heater 4
4 is attached. On the other hand, the engine 1 is housed in the engine room 46 of the housing 45. A ventilation outlet 45a is formed in the lower part of the housing 45,
A ventilation inlet 45b is formed on the upper part of the ventilation outlet 45.
A ventilation fan 47 that ventilates the inside of the housing 45 is attached to a. A room temperature sensor 48 is provided for detecting the "internal temperature of the engine room" in the engine room 46. A water jacket 49 for cooling is formed in the engine 1, and a water temperature sensor 51 for detecting the water temperature of the cooling water 50 in the water jacket 49 is provided.

The heater 44 and the ventilation fan 47 are operated by the electronic control means 53 by the detection signals of the room temperature sensor 48 and the water temperature sensor 51. In addition, 54 is a heat insulating material, and this heat insulating material 54 includes the collecting device 25, the collecting passage 28, the tube 35,
And the heater 44 is covered from the outside to keep them warm.

3 and 4 show a flow chart of the control means 53, and (P-1) to (P-12) show each step of the program.

In FIG. 3, if it is judged from the detection signal of the room temperature sensor 48 that the "engine room temperature" is lower than the set temperature T _A which is a predetermined temperature (P-
1) The heater 44 is made to function (P-2) to heat the oil separator 29, and in this oil separator 29, it is prevented that water vapor contained in the blow-by gas 24 causes dew condensation water, that is, Generation of emulsion sludge is prevented.

Next, if it is judged that the "engine room temperature" is above a certain set temperature T _B (P-3), the function of the heater 44 is stopped (P-4), and the oil separator is separated. Two
Excessive heating of 9 is prevented.

Thereafter, the above steps are sequentially repeated.

The set temperatures have a relationship of T _A <T _B.

In FIG. 4, the water temperature sensor 51 determines that the temperature of the cooling water 50 is equal to or higher than the set temperature T _a at (P-5), and further sets the "engine room temperature" at (P-6). If it is determined that the temperature is equal to or higher than the temperature T _b , the ventilation fan 47 is turned on (P-7), and the engine 1 as a whole is prevented from becoming too hot.

Next, in (P-8), it is determined that the water temperature of the cooling water 50 is below the set temperature T _c , or the same as above (P-8).
If it is determined in -8) that the water temperature has exceeded the set temperature T _c , and if it is determined in (P-9) that the "engine room temperature" is below the set temperature T _d , the ventilation fan 47 is turned off. Then, (P-10), the inside of the engine room 46 is maintained at a predetermined temperature or higher, and the generation of emulsion sludge in the oil separator 29 is prevented.

(Second Embodiment)

FIG. 5 shows a second embodiment.

In the figure, the element 3 of the oil separator 29
0 does not adsorb oil as in the first embodiment, but the mesh size of the element 30 and the element 30
It is structured to separate this oil by the effect of the surface treatment.

Other configurations and operations are the same as those of the first embodiment.

(Third Embodiment)

FIG. 6 shows a third embodiment.

According to this, the recovery passage 28 communicates the inside of the cylinder head cover 12 with the inside of the oil separator 29.
In addition, the inside of the cylinder head cover 12 is the cylinder head 7.
The cylinder 4 communicates with the inside of the crankcase 2 through a communication passage 40 formed in the cylinder 4. 41 is a baffle plate.

The blow-by gas 24 in the crankcase 2 is transferred to the communication passage 40, the cylinder head cover 12,
Further, the oil is sent to the oil separator 29 through the recovery passage 28.

According to this embodiment, there is an effect that the amount of oil discharged from the engine 1 to the outside can be suppressed to a small amount.

Other configurations and operations are similar to those of the first and second embodiments.

(Fourth Embodiment)

FIG. 7 shows a fourth embodiment.

According to this, instead of the room temperature sensor 48 in the first embodiment, the "oil separator temperature" of the oil separator 29 is obtained.
A temperature sensor 56 for detecting the temperature is provided.

The heater 44 and the ventilation fan 47 are operated through the control means 53 by the detection signals of the temperature sensor 56 and the water temperature sensor 51.

In the flow chart of the control means 53, in the above-mentioned FIGS. 3 and 4 and the description thereof, the term "engine room temperature" is replaced with "oil separator temperature" and the room temperature sensor 48 is used. This is the same as the one read as the temperature sensor 56.

The other structure is the same as that of the first embodiment.

(Fifth Embodiment)

8 to 10 show a fifth embodiment.

In FIGS. 8 and 9, the inside of the cylinder head cover 12 communicates with the inside of the crankcase 2 through a communication passage 40 formed in the cylinder head 7 and the cylinder 4. 41 is a baffle plate. The oil separator 29 includes a main oil separator 55. The main oil separator 55 has a casing 57 with a longitudinal axis and a circular cross section, and the inside of the casing 57 is divided into an upper chamber 60, an intermediate chamber 61, and a lower chamber 62 by upper and lower partition plates 58 and 59. It is partitioned.

A suction pipe 67 for introducing the blow-by gas 24 is attached to the lower chamber 62, and the downstream end of the recovery passage 28 is connected to the suction pipe 67. The end of the suction pipe 67 on the lower chamber 62 side is a thin nozzle 68, which opens upward. In addition, this nozzle 68
A hemispherical reversal plate 69 that faces downward and is opened downward is provided. An oil return passage 43 is attached to the bottom plate of the casing 57.

The lower partition plate 59 is made of punching metal having many holes. Also, the upper partition plate 5
8 has an annular shape in a plan view, and a partition cylinder 70 extends downward from the hole edge of the inner hole thereof, and the partition cylinder 70 has a small number of holes. The lower end opening of the partition cylinder 70 is closed by a bottom plate 71 near the upper part of the lower partition plate 59, and an oil hole 72 is formed in the bottom plate 71.

Between the outer peripheral wall of the casing 57 and the partition cylinder body 70, an element 73 composed of a large number of fine stainless steel wires bent in a zigzag shape is filled. A swirl vane 74 that swirls the blow-by gas 24 is provided in the upper chamber 60, and the swirl vane 74 is attached to an upper plate of the casing 57. The upper plate of the casing 57 has a discharge port 75.
Are formed.

In FIGS. 8 and 9, when the blow-by gas 24 is sucked into the lower chamber 62 through the suction pipe 67, the blow-by gas 24 is accelerated by the nozzle 68 and ejected. Then, the blow-by gas 24 is guided by the reversal plate 69 and suddenly reverses downward. At this time,
The oil in the blow-by gas 24 adheres to the inner surface of the reversal plate 69 and is separated from the blow-by gas 24, and this oil is discharged through the oil return passage 43.

On the other hand, the blow-by gas 24 after being inverted by the inversion plate 69 is the lower partition plate 59 and the element 7.
3 and the partition cylinder 70 in order, and the partition cylinder 7
0 to reach the upper chamber 60, where the swirl vanes 74
Thus, after being rotated around the vertical axis, it is discharged through the discharge port 34.

Then, when the blow-by gas 24 passes through the element 73 or is swung by the swirl vanes 74, the oil in the blow-by gas 24 is separated, and this oil passes through the oil holes 72 of the lower partition plate 59. It passes through and reaches the lower chamber 62, and then is discharged from the oil return passage 43 and returned to the oil pan 22.

In FIGS. 8 to 10, the recovery device 2 is used.
5 is equipped with a secondary oil separator 76. This secondary oil separator 76
Has a casing 78 having a circular cross section and a lateral axis, and the casing 78 includes a cylindrical portion 79, one side plate 80 for closing one axial opening of the cylindrical portion 79, and another side plate 81 for closing the other side opening. It is composed of. The inside of the casing 78 is divided into a narrow first chamber 83 and a wide second chamber 84 by a partition plate 82, and the partition plate 82 is formed of punching metal having a large number of holes. The second chamber 84
Is filled with an element 85 having the same structure as the element 30.

A suction port 86 is formed in the upper part of the one side plate 80, and the discharge port 75 of the oil separator 29 is the suction port 8.
6 is connected by a tube 87. Further, a discharge pipe 88 is provided that penetrates through the central portions of the one side plate 80, the partition plate 82, and the element 85, and one end of the discharge pipe 88 is surrounded by the other side plate 81 and the element 85, and the second chamber 84 is provided. Has a discharge port 34 that opens to a partial space and the other end opens to the outside of the casing 78. An oil return passage 43 is attached to the lower portion of the one side plate 80.

In the illustrated example, the oil return passage 43 extends horizontally from the one side plate 80, but the oil return passage 43 may extend obliquely downward from the one side plate 80. By doing so, the oil can be smoothly discharged from the first chamber 83.

The discharge port 75 of the main oil separator 55
The blow-by gas 24 sucked into the first chamber 83 through the suction port 86 of the sub oil separator 76 from the above sequentially passes through the partition plate 82, the element 85, and the discharge pipe 88, and is discharged from the discharge port 34. It is returned to the intake passage 14 via the tube 35.

In the above case, when the blow-by gas 24 passes through the element 85, the oil in the blow-by gas 24 is separated, the oil passes through the partition plate 82 and reaches the first chamber 83, and then the oil is removed. It is discharged from the return passage 43 and returned to the oil pan 22.

Among the other constitutions and operations, the control device 53 and the temperature sensor 56 are the same as those in the fourth embodiment.
Others are the same as the third embodiment.

[0081]

According to the first aspect of the present invention, the engine is connected to the air cleaner through the intake passage, and the outside air is introduced into the engine through the air cleaner and the intake passage in this order. An oil separator for inhaling the blow-by gas generated from the blow-by gas to separate the oil contained in the blow-by gas is provided separately from the engine, and the blow-by gas after the oil is separated by the oil separator is used for the intake passage. In an oil separation device for blow-by gas of an engine, the oil separation passage is provided for returning the oil separated by the oil separator to an oil storage portion in the crankcase of the engine, and the oil separator. Since the heater for heating is provided, the following effects are obtained.

That is, if the oil separator is provided separately from the engine, the temperature of the oil separator tends to be low because the oil separator is not easily heated by the engine. Therefore, when the blow-by gas is sent to the oil separator, the water vapor in the blow-by gas is condensed to generate condensed water, and the acid gas generated by the combustion of the engine is dissolved in the condensed water to become strongly acidic.

Since the condensed water mixes with the oil separated here in the oil separator, emulsion sludge having strong acidity is generated, and the sliding contact portion between the cylinder and the piston is corroded. It causes inconvenience.

Therefore, in the present invention, as described above,
An oil return passage is provided for returning the oil separated by the oil separator to the oil reservoir in the crankcase of the engine.

Therefore, the oil separated by the oil separator passes through the oil return passage from the oil separator side without passing through the sliding contact portion between the cylinder and the piston, and more directly passes through the oil storage portion. Will be returned to.

Therefore, since it is possible to prevent the oil from passing through the sliding contact portion between the cylinder and the piston toward the oil storage portion side, even if the oil is acidic,
It is prevented that the sliding contact portion is corroded by the acidity of the oil.

Further, as described above, the heater for heating the oil separator is provided.

Therefore, since the oil separator is heated by the heater and kept at a high temperature to some extent, the oil contained in the blow-by gas is separated when the blow-by gas is sent to the oil separator. On the other hand, the steam in the blow-by gas is prevented from becoming condensed water,
This water vapor passes through the oil separator as a gas.

Therefore, the dew condensation water is prevented from being mixed with the oil separated by the oil separator, and the generation of emulsion sludge is prevented.

As a result, it is possible to more effectively prevent the sliding contact portion between the cylinder and the piston from being corroded by the acidity of the emulsion sludge, and the oil in the oil storage portion corrodes each lubricating portion. It is also prevented. Further, the emulsion sludge is also prevented from leaking the spark plug of the engine, so that a start failure and a misfire are prevented, and the engine performance is kept good.

Moreover, since the oil separator is heated by the heater to prevent the generation of emulsion sludge, the oil separated by the oil separator smoothly flows through the oil return passage and is then fed into the crankcase. Will be returned to the oil storage part.

Therefore, since the oil return passage does not need to have a too large cross-sectional area, the oil separation device effectively prevents the corrosion of the sliding contact portion and the like and improves the engine performance as described above. The structure can be simplified while achieving various effects of maintaining.

According to the invention of claim 2, in the invention of claim 1, an engine room for accommodating the engine is provided,
A room temperature sensor for detecting the temperature in the engine room is provided, and when the temperature in the engine room is lower than a predetermined temperature by the detection signal of the room temperature sensor, the heater is made to function.

Therefore, even though the temperature around the oil separator is high, it is possible to prevent the oil separator from being unnecessarily excessively heated, and thus wasteful consumption of heat in the heater is prevented. Suppressed.

According to the invention of claim 3, in the invention of claim 1, a temperature sensor for detecting the temperature of the oil separator is provided.

Therefore, since the temperature of the oil separator is detected more directly, excessive heating of the oil separator can be prevented more accurately, and wasteful consumption of heat in the heater can be more reliably achieved. To be prevented.

[Brief description of drawings]

FIG. 1 is a simplified partial cross-sectional view of a first embodiment.

FIG. 2 is a partially enlarged sectional view of FIG. 1 in the first embodiment.

FIG. 3 is a flowchart of the first embodiment.

FIG. 4 is a flowchart of the first embodiment.

FIG. 5 is a diagram corresponding to FIG. 2 in the second embodiment.

FIG. 6 is a view corresponding to FIG. 1 in the third embodiment.

FIG. 7 is a view corresponding to FIG. 1 in a fourth embodiment.

FIG. 8 is a view corresponding to FIG. 1 in a fifth embodiment.

FIG. 9 is a sectional view of an oil separator according to a fifth embodiment.

FIG. 10 is a sectional view taken along line 10-10 of FIG. 9 in a fifth embodiment.

FIG. 11 is a diagram corresponding to FIG. 1 in a conventional example.

[Explanation of symbols]

 1 Engine 2 Crankcase 14 Intake Passage 15 Air Cleaner 22 Oil Pan (Oil Storage) 23 Lubricating Oil 24 Blowby Gas 29 Oil Separator 34 Discharge Port 43 Oil Return Passage 44 Heater 46 Engine Room 48 Room Temperature Sensor 56 Temperature Sensor

Claims (3)

[Claims] 1. An air cleaner is communicated with an engine through an intake passage, and outside air is introduced into the engine through the air cleaner and the intake passage in sequence, while blow-by gas generated from the engine is sucked into the engine. An oil separator for separating the oil contained in the blow-by gas is provided separately from the engine, and the blow-by gas after the oil has been separated by the oil separator is introduced into the intake passage. In the oil separator for gas, an oil return passage is provided for returning the oil separated by the oil separator to the oil storage portion in the crankcase of the engine.
An oil separation device for blow-by gas for an engine, which is provided with a heater for heating the oil separator. 2. An engine room for accommodating an engine is provided, and a room temperature sensor for detecting a temperature in the engine room is provided. When the temperature in the engine room is lower than a predetermined temperature by a detection signal of the room temperature sensor, a heater is provided. The oil separation device for blow-by gas for an engine according to claim 1, wherein the oil separation device is made to function. 3. A temperature sensor for detecting the temperature of the oil separator is provided, and the heater is made to function when the temperature of the oil separator is lower than a predetermined temperature by the detection signal of the temperature sensor. The oil separation device for blow-by gas of the engine according to.