JP2007100551A - Breather device of engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a breather device of an engine for surely performing separated oil returning even to a large quantity of blow-by gas by surely returning separated oil in an oil pan in an internal breather device arranged in a gear case and an external breather device installed outside the gear case. <P>SOLUTION: The internal breather device is arranged inside the gear case, and the external breather device is arranged for performing secondary separation of the oil in the blow-by gas passing through the internal breather device. and is arranged to be partitioned from a gear storage chamber by a partition plate and to be partitioned from a turning passage outside a partition wall. An oil return passage is formed for sending out the oil separated by the secondary separation in the external breather device, and an oil return port is formed for draining the oil passing through the oil return passage to the oil pan. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a breather device for an engine that is applied mainly to a vehicle engine and separates oil from blow-by gas generated inside the engine.

  FIG. 5 shows a configuration in which blowby gas leaking from around the piston of the engine is separated from the blowby gas by a breather device installed outside the gear case at the front of the engine, and the blowby gas is sent to the intake system of the engine 1 is a conventional example of a breather device for an engine.

In FIG. 5, reference numeral 1 denotes a gear case made of a cast product such as an aluminum casting, which is fixed to a front end surface of a crankcase (not shown) with a plurality of bolts. 04 is a blow-by gas inlet into the gear case 1, 05 is a blow-by gas outlet, and the blow-by gas is in the gear case 1.
It enters the gear case 1 from the lower blow-by gas inlet 04 and is sent from the blow-by gas outlet 05 provided on the upper side of the gear case 1 to an exterior breather device (not shown) mounted outside the gear case 1.
In the exterior breather device, the oil in the blow-by gas is separated, and this separated oil is introduced into the gear case 1 from two return oil inlets 03 provided in the gear case 1 and formed on the side of the idler gear in the gear case 1. The oil return passages 02 and 02 are returned to an oil pan (not shown) from an oil return port 06 connected to the upper side of the curved lower end of the oil return passages 02 and 02.

As one of engine breather devices, a technique disclosed in Japanese Patent Application Laid-Open No. 2004-84506 is provided.
In such a technique, a vertical partition that forms the outer wall of the gear case divides the first separation chamber inside the gear case into a second separation chamber that is externally mounted on the gear case, and the first separation chamber and the second separation chamber are disposed above the partition. A communication passage with the two separation chambers, an oil discharge passage at the lower part of the partition wall, an exhaust pipe leading to the intake system in the second separation chamber, and a first-stage oil in the first separation chamber. The separated blow-by gas is guided to the upper part of the second separation chamber through the communication passage, flows downward through the second separation chamber to perform second-stage oil separation, and supplies the blow-by gas to the intake system through the exhaust pipe. Is configured to do.

JP 2004-84506 A

In the prior art shown in FIG. 5, when the separated oil from the exterior breather device passes through the oil return passages 02 and 02 formed on the side of the idler gear, the flow of blow-by gas accompanying the rotation of the idler gear The oil separation function cannot be performed sufficiently by being carried away and sent to the exterior breather device side together with the blow-by gas. As a result, abnormal combustion is induced, oil consumption increases, the intake pipe inner surface, etc. Problems such as oil adhesion to various parts of the engine occur.
Also, in an automotive engine equipped with an exhaust turbocharger, when the exhaust brake is activated, the turbocharger lubricates from the slight gap between the turbine shaft bearing and the sliding portion of the turbine shaft as the exhaust pressure increases. Exhaust gas may flow into the return passage as blow-by gas and blow out in a large amount into the crankcase while entraining the oil in the supercharger lubrication return passage.
As a result, the oil deterioration of the oil pan is promoted, and the pressure in the crankcase is excessively increased, so that the blow-by gas flows backward from the oil return port 06 to the exterior breather device side via the oil return passage 02. It is easy to happen.

  Therefore, in view of the problems of the prior art, the present invention ensures that the separated oil in the internal breather device provided in the gear case and the exterior breather device mounted on the outside of the gear case is reliably dispersed in the oil pan without scattering in the gear case. In this way, the separation oil is reliably returned to a large amount of blow-by gas, thereby inducing abnormal combustion, increasing oil consumption, and attaching oil to various parts of the engine such as the intake pipe inner surface. It is an object of the present invention to provide an engine breather device that prevents the occurrence of defects.

  The present invention achieves such an object. In an engine breather device that separates oil from blow-by gas generated inside an engine, a gear case that houses a gear that transmits the engine to each engine accessory, and the gear case includes the gear case. The blow-by gas introduced from a blow-by gas inlet opening at the upper part of the gear case is swung and allowed to flow by being partitioned from a gear storage chamber in which the gear is stored by a partition plate attached to a protruding partition wall. An internal breather device having an annular swirl passage for primarily separating oil from the gas, and sending out the blow-by gas after the first separation from a blow-by gas outlet opening at a downstream end of the swirl passage; The blow-by communicated with the gas outlet and separated primarily by the internal breather device. An exterior breather device for secondarily separating oil from the gas, and the partition plate and the gear storage chamber, and the partition wall and the swirl passage, and the exterior breather device at the start end. The oil return is formed with a separated oil inlet for sending the oil secondarily separated into the gear case and an oil return port for discharging the second separated oil flowing from the separated oil inlet to the oil pan at the end. A passage is provided (claim 1).

  In this invention, preferably, the oil return passage is formed from the start end to the end through an oil sump passage that extends downward along the partition wall and curves upward at the lowermost portion (invention 2). .

  According to the present invention, an internal breather device provided with an annular swirl passage which is formed in a gear case and defined as a gear storage chamber and swirls and flows blowby gas to perform primary separation of oil in the blowby gas; An exterior breather device that performs secondary separation of oil in blow-by gas that is attached to the outside of the gear case and passes through the internal breather device, and is separated from the gear storage chamber and the swirl passage formed in the gear case And an oil return passage through which oil separated in the secondary separation in the exterior breather device flows is formed, and the separated oil in the exterior breather device is passed through the oil return passage. Since it is configured to return to the oil pan from the oil return port, the separated oil in the exterior breather device is formed separately from the gear storage chamber in the gear case. By passing the oil return passages, it is possible to return to reliably oil pan separating oil from the outer breather device.

  Therefore, according to the present invention, even when the amount of blow-by gas increases and the amount of separated oil increases, it becomes possible to reliably return the separated oil from the exterior breather device to the oil pan as described above. As the separated oil is taken away by the flow of blow-by gas accompanying the rotation of the gear and is sent to the exterior breather device again together with the blow-by gas, abnormal combustion is induced due to the deterioration of the oil separation function, and oil consumption is reduced. It is possible to prevent the occurrence of problems such as increase and oil adhesion to various parts of the engine such as the inner surface of the intake pipe, and to obtain a breather device capable of maintaining a high separation oil processing function even for a large amount of blowby gas.

In addition, since the oil return passage is formed by using the outer space through the partition wall that forms a part of the annular swirl passage of the internal breather device formed in the gear case, the gear storage chamber is formed by a partition plate in the gear case. The internal breather device and the oil return passage from the exterior breather device can be formed adjacent to each other through a partition wall in a section formed in a separate chamber, so that the internal breather device and the exterior breather device have a simple and compact structure. Since the oil return passage from the exterior breather device can be formed with a small number of parts without requiring special piping, the device cost can also be reduced.

  If the oil return passage is formed from the start end to the end via an oil sump passage that extends downward along the partition wall and curves upward at the bottom (Claim 2), the exhaust brake operates. Even when a large amount of blow-by gas blows into the crankcase and the internal pressure of the crankcase rises as in the case of time, it extends downward from the swirl passage side of the internal breather device so that it curves at the bottom and reverses upward. It is possible to prevent the blow-by gas in the crankcase from flowing back into the oil return passage due to the oil accumulated in the oil reservoir passage formed in the above.

  Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this example are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.

  1 is a sectional view taken along a partition plate mounting seat of a gear case in a breather device for a vehicle engine according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line BB in FIG. 1, and FIG. FIG. 4 is a sectional view taken along line CC in FIG.

  1-4, 1 is a gear case made of a cast product such as an aluminum casting, and is fixed to a front end surface of a crankcase (not shown) with a plurality of bolts. The gear case 1 houses a gear train such as a timing gear including an idler gear 2 (see FIGS. 3 to 4) and a driving gear for auxiliary equipment. 2a is the rotation center of the idler gear 2.

Reference numeral 200 denotes an internal breather device provided inside the gear case 1 and is configured as follows.
Reference numeral 3 denotes a partition plate made of a metal plate such as a steel plate or a resin plate. As shown in FIG. 3, a gear train including the idler gear 2 is housed in the gear case 1 by the partition plate 3 in the engine axial direction. It is divided into a gear storage chamber 7 and a blow-by gas swirl chamber 6 in which blow-by gas swirls and flows.
The partition plate 3 is manufactured by molding an integrated plate made of a metal plate such as a steel plate or a resin plate. As shown in FIG. 3, the shape of the gear cutout portion 8 recessed in the side surface of the idler gear 2 is formed. The concave portion 3a is formed by being depressed according to the above. Accordingly, a turning passage 6a described later is formed by the recess 3a. 3b is a convex part of the partition plate 3, and a slight space is formed between the inner surface 1z of the gear case 1. Accordingly, since the blow-by gas is difficult to flow into this small space, a swirl flow is easily generated in a swirl passage 6a described later.

As shown in FIGS. 1 and 3 to 4, the partition plate 3 is attached to the inside of the front surface of the gear case 1, and the partition plate serves as a partition partitioning the blow-by gas swirl chamber 6 and an oil return passage 30 to be described later. A mounting seat 12 protrudes toward the blow-by gas swirl chamber 6 inside the gear case 1, and the partition plate 3 is attached to the partition plate mounting seat 12 by a caulking member 13.
Therefore, the partition plate 3 is formed with a space between the inner surface 1z of the gear case 1 at a portion other than the contact surface between the partition plate 3 and the partition plate mounting seat 12, and the space portion is The blow-by gas swirl chamber 6 is provided.

That is, as shown in FIG. 1, the partition plate 3 manufactured by molding the integral plate as described above is attached to the partition plate mounting seat 12 of the gear case 1 by the caulking member 13, and as shown in FIGS. Thus, a blow-by gas swirl chamber 6 such as a swirl passage 6a, an oil reservoir 6b, and an oil sump passage 10 is formed between the front surface 3y of the partition plate 3 and the inner surface 1z of the gear case 1.
As shown in FIG. 1, the turning passage 6 a is formed in an annular shape that is concentric (not necessarily concentric) with the rotation center 2 a of the idler gear 2.
Reference numeral 4 denotes a blow-by gas inlet. As shown in FIG. 3, the upper part of the partition plate 3 is folded inward to form a bent part 3d, and the blow-by gas is interposed between the bent part 3d and the upper part of the inner surface 1z of the gear case 1. A gas inlet 4 is formed.
1, 2, and 4, 5 is a blow-by gas outlet, which opens at the downstream end of the swivel passage 6a of the gear case 1 as shown in FIG. 1 and is connected to an exterior breather device 100 described later.

As shown in FIGS. 1 and 3, the blow-by gas inlet 4 is installed above the rotation center 2 a of the idler gear 2 and connected to the inlet passage of the turning passage 6 a, and the blow-by gas outlet 5 is connected to the idler gear 2. Is installed above the rotation center 2a and opens at the downstream end of the turning passage 6a.
As a result, the swirl passage 6a is formed with a swivel angle of 180 ° or more around the rotation center 2a of the idler gear 2. Therefore, the blow-by gas introduced from the blow-by gas inlet 4 into the swirl passage 6a is swirled. The passage 6a turns by 180 ° or more and is discharged to the blow-by gas outlet 5.
Reference numeral 11 denotes an oil cutting projection projecting from the lower portion of the swirling passage 6a. The blow-by gas swirling the swirling passage 6a collides with the oil cutting projection, thereby separating the oil in the blow-by gas.

An oil sump 6b is formed in a lower part of the swivel passage 6a, and an oil sump passage 10 is formed in a lower part of the oil sump 6b. The oil sump passage 10 is formed in a U-shape that extends downward from the oil sump 6b side and curves at the bottom and reverses upward. An oil return port 9 is opened at the top of the oil reservoir passage 10 and communicates with an oil pan (not shown).
With this configuration, even when a large amount of blow-by gas blows into the crankcase and the internal pressure of the crankcase increases as in the case of the exhaust brake being operated, the oil accumulated in the oil passage 10 It is possible to prevent the blow-by gas from flowing back from the inside of the case to the blow-by gas swirl chamber 6 side of the gear case 1.

In FIG. 1, 30 is an oil return passage formed integrally with the gear case 1 in the gear case 1, and the outer portion of the turning passage 6a is provided with a partition wall 30c which is a part of the partition plate mounting seat 12 through the partition wall 30c. The turning passage 6a and the gear housing chamber 7 are formed independently of the partition wall 30c. The oil return passage 30 has a U-shaped oil reservoir passage 35 that is curved at the bottom and reverses upward, and an oil return port that communicates with the oil pan at the end of the oil reservoir passage 35. 32.
Even in such a configuration, when a large amount of blow-by gas blows into the crankcase and the internal pressure of the crankcase increases as in the case of the operation of the exhaust brake device, the oil accumulated in the U-shaped oil reservoir passage 35 is increased. Therefore, it is possible to prevent the blow-by gas from flowing back from the oil pan side to the oil return passage 30 side.
Further, since the oil return passage 30 is formed so as to be separated from the gear housing chamber 7 by the partition plate 3, the oil in the oil return passage 30 may be taken away by the flow of blow-by gas accompanying the rotation of the idler gear. Can be prevented.

  Next, in FIG. 2, reference numeral 100 denotes an exterior breather device installed outside the gear case 1, and the case 102 is formed so as to protrude from the outer surface of the gear case 1 and is integrally formed with the gear case 1, or It is formed separately from the gear case 1 and is fixed to the gear case 1 with a plurality of bolts. 103 is a collision wall for oil separation of the exterior breather device 100, 104 is an oil separation chamber, 33 is a separation gas passage, and blow-by gas introduced into the oil separation chamber 104 from a blow-by gas outlet 5 formed in the gear case 1. 2 flows as indicated by an arrow in FIG. 2 and collides with the collision wall 103 in the oil separation chamber 104 to separate the oil from the blow-by gas.

The separation gas after oil separation from the blow-by gas enters the separation gas chamber 1w formed in the upper part of the gear case 1 through the separation gas passage 33, and enters the intake system from the separation gas outlet 34 above the separation gas chamber 1w. It comes to be supplied.
On the other hand, the separated oil 101 separated from the blow-by gas in the oil separation chamber 104 of the exterior breather device 100 enters the oil return passage 30 in the gear case 1 from the separated oil inlet 31 as shown in FIGS. ing.

In this embodiment, blow-by gas introduced from the blow-by gas inlet 4 of the internal breather device 200 into the swirl passage 6a of the blow-by gas swirl chamber 6 swirls in the swirl passage 6a as shown by the arrows in FIG. And the oil is separated by colliding with the oil cutting protrusion 11. The blow-by gas from which the oil has been separated by the primary separation action is sent to the oil separation chamber 104 of the exterior breather device 100 through the blow-by gas outlet 5 as shown in FIG.
Further, as described above, the oil separated from the blow-by gas in the internal breather device 200 is discharged to an oil pan (not shown) through the oil reservoir 6b, the oil reservoir passage 10, and the oil return port 9.

On the other hand, the blow-by gas introduced into the oil separation chamber 104 of the exterior breather device 100 after the primary separation of oil in the internal breather device 200 flows as indicated by the arrows in FIG. A secondary oil separation operation is performed to separate the oil from the blow-by gas by colliding with the internal collision wall 103.
Due to the secondary separation action, the separation gas after oil separation from the blow-by gas passes through the separation gas passage 33 and enters the separation gas chamber 1w formed in the upper part of the gear case 1, and above the separation gas chamber 1w. The gas is supplied from the separated gas outlet 34 to the intake system of the engine and mixed into the intake air.
Further, the separated oil 101 separated from the blow-by gas in the oil separation chamber 104 by the secondary separation action in the exterior breather device 100 is returned to the oil case 1 in the gear case 1 from the separated oil inlet 31 as shown in FIGS. The oil enters the passage 30, flows in the oil return passage 30 as indicated by the arrow in FIG. 1, passes through the U-shaped oil reservoir passage 35 and the oil return port 32, and is discharged to an oil pan (not shown).

  Therefore, according to such an embodiment of the present invention, the gear case 1 is formed in a chamber separate from the gear housing chamber 7 and swirling and flowing the blow-by gas to perform the primary separation of the oil in the blow-by gas. An internal breather device 200 having a swirling passage 6a and an exterior breather device 100 that is attached to the outside of the gear case 1 and performs secondary separation of oil in blow-by gas that has passed through the internal breather device 200 are provided side by side. 1 is an oil return passage through which oil separated in the secondary separation in the exterior breather device 100 is sent to an outer portion of the annular breathing passage 6a of the inner breather device 200 formed in the outer space via a partition wall 30c. 30, and the oil separated in the exterior breather device 100 passes through the oil return passage 30 and the oil reservoir passage 35. Since the oil return port 32 at the end of the passage 30 is returned to the oil pan, the separated oil in the exterior breather device 100 is formed separately from the gear storage chamber 7 in the gear case 1 and separately from the oil return. By passing the passage 30 and the oil reservoir passage 35, the separated oil from the exterior breather device 100 can be reliably returned to the oil pan without being affected by the gear housing chamber 7.

  Therefore, according to the embodiment, as in the prior art of FIG. 5, the separated oil is carried away by the flow of blow-by gas accompanying the rotation of the gear and is sent again to the exterior breather device 100 side together with the blow-by gas. It is possible to prevent the occurrence of problems such as induction of abnormal combustion due to a decrease in the oil separation function, increase in oil consumption, and adhesion of oil to various parts of the engine such as the intake pipe inner surface.

In addition, the oil separated in the secondary separation in the exterior breather device 100 using the outer space through the partition wall 30c of the annular swirl passage 6a of the internal breather device 200 formed in the gear case 1 is removed. Since the oil return passage 30 to be delivered is formed, the oil return passage 30 from the internal breather device 200 and the exterior breather device 100 is formed in a portion of the gear case 1 that is partitioned by the partition plate 3 and separated from the gear storage chamber 7. Can be formed adjacent to each other via the partition wall 30c, and the internal breather device 200 and the oil return passage 30 from the exterior breather device 100 can be integrally formed with a simple and compact structure, and special piping is required. The oil return passage 30 and the like from the exterior breather device 100 can be formed with a small number of parts. As a result, an effect of reducing the apparatus cost can be obtained.
Further, since the caulking method using the caulking member 13 is used as a means for attaching the partition plate 3 to the gear case 1, it is more suitable than the attaching means using bolts and screws for vibration of the gear case 1 body and air vibration. It is difficult to sag.

  Further, as shown in FIG. 1, since the U-shaped oil reservoir passage 35 is formed in the oil return passage 30, a large amount of blow-by gas is blown into the crankcase as when the exhaust brake is operated. Even when the internal pressure rises, it is possible to prevent the blow-by gas from flowing back from the inside of the crankcase to the oil return passage 30 due to the oil accumulated in the oil sump passage 35 formed in a U shape.

  According to the present invention, separation oil in the internal breather device provided in the gear case and the exterior breather device mounted outside the gear case is reliably returned to the oil pan, so that a large amount of blow-by gas is separated. Providing an engine breather device that can reliably perform oil return processing and prevent malfunctions such as induction of abnormal combustion, increased oil consumption, and oil adhesion to various parts of the engine such as the inner surface of the intake pipe it can.

It is principal part sectional drawing (BB sectional drawing of FIG. 3) including the blow-by gas inlet along the idler gear centerline which shows the breather apparatus of the engine for vehicles which concerns on the Example of this invention. It is principal part sectional drawing containing the blowby gas outlet in the said Example (CC sectional view taken on the line of FIG. 3). It is the sectional view on the AA line of FIG. 1 which shows the planar shape of the attachment seat of the partition plate in the said Example. It is a component figure of the partition plate in the said Example, (A) is a top view, (B) is the BB sectional drawing in (A). It is an example of the breather apparatus in the conventional engine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gear case 2 Idler gear 2a Center of rotation 3 Partition plate 3a Concave 4 Blow-by gas inlet 5 Blow-by gas outlet 6 Blow-by gas swirl chamber 6a Swirling passage 7 Gear storage chamber 8 Gear fill-out portion 9, 32 Oil return port 10 Oil reservoir passage 11 Oil cut Protrusion 12 Partition plate mounting seat (partition wall)
30 Oil return passage 31 Breather inlet oil passage 33 Separation gas passage 35 Oil reservoir passage 100 Exterior breather device 200 Internal breather device

Claims (2)

In an engine breather device that separates oil from blow-by gas generated inside an engine, a gear case that houses a gear that transmits the engine to each engine accessory, and a partition plate that is attached to a partition wall that projects from the gear case The ring is separated from a gear storage chamber in which the gear is stored, and a ring-shaped ring that firstly separates oil from the blow-by gas by swirling and flowing blow-by gas introduced from a blow-by gas inlet opening at an upper portion of the gear case. An internal breather device that has a swirl passage, and that blows out the blow-by gas after the first separation from a blow-by gas outlet that opens at a downstream end of the swirl passage; and communicates with the blow-by gas outlet; An exterior block for secondarily separating oil from the blowby gas that has been primarily separated. The device is separated from the gear storage chamber by the partition plate, and is disposed so as to be separated from the swirl passage by the partition wall, and the oil secondarily separated by the exterior breather device at the start end. An oil return passage having a separation oil inlet for feeding into the gear case and an oil return port for discharging secondary separated oil flowing from the separation oil inlet to an oil pan at the end is provided. Engine breather device.   2. The engine according to claim 1, wherein the oil return passage extends downward from the start end along the partition wall and is formed to the end through an oil sump passage that is curved upward at a lowermost portion. Breather device.

Images