JP5997513B2 - Oil separator - Google Patents

Description

  The present invention relates to an oil separator for separating oil in blow-by gas of an internal combustion engine.

  In automobile engines, etc., the blow-by gas that leaks into the crankcase from the gap between the piston and cylinder contains a large amount of HC (hydrocarbon), so it is returned to the intake system and recombusted with the mixture. The method is widespread. Since the blow-by gas contains oil obtained by atomizing engine oil or the like, the gas after removing this oil is sent to the intake system. As means for separating oil mist in blow-by gas, various types of oil separators (labyrinth type, inertial collision type, cyclone type, etc.) are known.

  Conventionally, an oil separator of this type that is attached to a cylinder block of an engine is known (see Patent Document 1). In this conventional oil separator, a closed space is formed between the recess of the cylinder block, and this closed space is divided into an inner chamber and an outer chamber by a partition plate, and the inner chamber is further divided by a partition wall portion. The chamber is divided into a first inner chamber communicating with the crankcase and a second inner chamber communicating with the blow-by gas discharge port, and oil is separated in each chamber.

JP 2004-245176 A

  By the way, the conventional oil separator used for an automobile engine or the like was intended to collect oil particles of up to about 10 to 20 μm, but it has a relatively small diameter (around 1 μm) from the viewpoint of recent exhaust gas regulations and environmental loads. It is desired that the oil particles (oil mist) can be efficiently collected. However, in the prior art described in Patent Document 1, although three oil separation chambers can be provided to effectively improve the oil separation performance, the above-described collection efficiency of relatively small diameter oil Was not always enough.

  The present invention has been devised in view of such problems of the prior art, and achieves good collection efficiency by including particles in oil having a relatively small diameter (around 1 μm) by a compact configuration. The main object is to provide an oil separator that can be used.

  An oil separator according to a first aspect of the present invention is an oil separator for separating oil in blow-by gas of an internal combustion engine, and is installed so as to cover a part of a side wall of the internal combustion engine. A cover member that forms a flow space for the blow-by gas between the side wall, a baffle plate provided in the flow space, and a cyclone attached to the inside of the cover member that is in the flow space, The cyclone includes a cyclone main body having a cyclone chamber formed therein, a gas introduction pipe for introducing the blow-by gas into the cyclone chamber, and the blow-by gas after separating the oil from the cyclone chamber to the outside. A gas outlet pipe, and a flow path inlet in the gas inlet pipe is the baffle plate in the circulation space. The opening on the downstream side, the flow path outlet in the gas discharge tube is characterized by communicating with the outside of the cover member which is outside the flow space.

  The oil separator according to the first aspect collects oil particles having a relatively large diameter by a baffle plate located upstream of the flow-by space of the blow-by gas, and has a relatively small diameter (around 1 μm) by a cyclone located downstream. ) Oil particles are collected, it is possible to achieve good collection efficiency by including particles in a relatively small diameter oil. There is also an advantage that a compact configuration can be maintained without complicating the flow path in the distribution space.

  The second aspect of the present invention relates to the first aspect, wherein the cyclone is further connected to one end of the cyclone main body, and further includes an oil collection box in which a collection chamber communicating with the cyclone chamber is formed. And a valve for discharging oil from the oil collection box is provided on the side wall of the internal combustion engine in the oil collection box.

  Since the oil separator according to the second side surface is provided with a valve inside the oil collection box (side wall side of the internal combustion engine), an increase in the size of the oil separator (that is, the blow-by gas distribution space) in the gas distribution direction is suppressed. can do.

  In the third aspect of the present invention, with respect to the first or second aspect, the baffle plate is U-shaped so as to cover the lower surface side of the portion where the valve is provided in the oil collection box. It has the part.

  The oil separator according to the third aspect can realize a compact configuration in which the distance between the cyclone (oil collecting box) and the baffle plate is reduced, and the oil discharged from the oil collecting box can be reduced. It can be guided in a predetermined direction by the U-shaped part of the baffle plate.

  According to a fourth aspect of the present invention, with respect to the first or second aspect, the oil collecting box protrudes toward the side wall of the internal combustion engine from the lower part of the box provided with the valve and the lower part of the box. And an upper portion of the box provided.

  The oil separator according to the fourth aspect has a required capacity of the collection chamber in the oil collection box even when a valve is provided inside the oil collection box (side wall side of the internal combustion engine) to secure an oil discharge path. Can be secured.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a center axis of the cyclone main body is disposed to be inclined with respect to a gas flow direction in the flow space. To do.

  The oil separator according to the fifth aspect relates to a cyclone main body having a large size in the central axis direction, and the central axis is inclined with respect to the gas distribution direction, so that the gas distribution direction of the oil separator (blow-by gas distribution space) The increase in the size of can be effectively suppressed.

  As described above, according to the present invention, the compact configuration has an excellent effect that it is possible to achieve good collection efficiency by including particles in oil having a relatively small diameter (around 1 μm).

Rear perspective view of oil separator according to the present invention Front perspective view of the oil separator shown in FIG. Sectional drawing of the principal part showing the installation state of the oil separator shown in FIG. IV-IV sectional view in FIG. Sectional view taken along line V-V in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description, the term indicating the direction follows the direction indicated by the arrow in FIG. However, the practical arrangement of the oil separator according to the present invention is not necessarily limited to those directions.

  1 and FIG. 2 are a rear perspective view and a front perspective view of an oil separator according to the present invention, respectively, FIG. 3 is a cross-sectional view of a main part showing an installation state of the oil separator shown in FIG. 4 is a sectional view taken along line IV-IV in FIG. 2, and FIG. 5 is a sectional view taken along line VV in FIG.

  The oil separator 1 is used as means for separating oil (mist) in blow-by gas in an automobile engine (not shown). The oil separator 1 is mainly formed of a synthetic resin material, and is installed so as to cover a part of the side wall 7 (see FIG. 3) of the cylinder block 6, so that the upper and lower concave portions 7 a and 7 b formed on the side wall 7 are formed. And a concave cover member 2 that forms a flow space 8 for blow-by gas between them, a tangential inflow type cyclone 3 attached to the rear surface side of the cover member 2, and a rear surface (inner surface) of the cover member 2 projecting rearward And a baffle plate 4 provided. The circulation space 8 communicates with an engine crank chamber (not shown).

  The cover member 2 includes a cover body 11 having a concave shape, and a flange portion 12 provided so as to surround the cover body 11. An annular groove 13 provided between the periphery of the cover body 11 and the flange portion 12 accommodates a seal member (not shown) interposed between the cover 7 and the side wall 7 when attached to the cylinder block 6. The A cyclone 3 is bolted to the center of the rear surface side of the cover body 11. The flange portion 12 is provided with a plurality of bolt insertion holes 15 for bolting the cover member 2 to the side wall 7 of the cylinder block 6 (see FIG. 3).

  Further, in the cover member 2, the cyclone 3 is covered from the cyclone 3 (more specifically, the left side wall of the box lower part 41, which will be described later) so that a part of the internal space of the cover body 11 is vertically divided on the left side of the cyclone 3. A partition wall 14 a extending substantially in the left-right direction to the left edge of the main body 11 is provided. Similarly, on the right side of the cyclone 3, a partition wall 14 b is provided that extends substantially in the left-right direction from the cyclone 3 (more specifically, the right side wall of the box upper part 42 described later) to the right edge of the cover body 11. Yes. The rearward protruding length of the partition wall 14b is set shorter than that of the partition wall 14a.

  In the cover member 2, an internal space of the cover member 2 that forms a part of the circulation space 8 is formed by the virtual surface including the rear surface 12 a (see FIG. 4) of the flange portion 12 and the concave rear surface (inner surface) of the cover member 2. Is defined.

  As shown in FIG. 4, the cyclone 3 includes a cyclone main body 21 in which a cyclone chamber S is formed, and a gas introduction pipe 22 that is connected to a side portion of the cyclone main body 21 and introduces blow-by gas into the cyclone chamber S (see FIG. 4). 1), a gas outlet pipe 23 connected to the upper part (here, the left end side) of the cyclone main body 21 and guiding the oil-separated gas (hereinafter referred to as a separated gas) from the cyclone chamber S to the outside, and the cyclone main body 21 is provided with a substantially rectangular parallelepiped oil collecting box 24 that is connected to the lower part (here, the right end side) of 21 and collects the separated oil.

  The cyclone main body 21 has a cylindrical portion 31 and a hollow conical portion 32 that continues to the lower portion (here, the right end side) of the cylindrical portion 31. The end of the hollow conical portion 32 on the reduced diameter side is connected to the side portion (the left side wall 24a) of the oil collection box 24. The cylindrical portion 31 and the hollow conical portion 32 are arranged coaxially with the central axis C of the oil separator 1, and the cyclone chamber S is formed by the hole 31 h of the cylindrical portion 31 and the tapered hole 32 h of the hollow conical portion 32 connected to the lower end thereof. The side peripheral surface of the is defined. The central axis C is disposed so as to be inclined with respect to a flow direction (vertical direction) of blow-by gas described later. The cyclone 3 is inclined so that the cyclone main body 21 is on the upper side and the oil collection box 24 is on the lower side. Thereby, the size of the oil separator 1 (blow-by gas distribution space 8) in the gas distribution direction is made compact, and the oil separator 1 can be arranged in a narrow installation space in the engine of the automobile.

  The gas introduction pipe 22 (see FIG. 1) is formed integrally with the cylindrical portion 31 of the cyclone main body 21. The gas introduction pipe 22 has a flow path having a rectangular cross section, and communicates with the cyclone chamber S via a flow path outlet on one end side (not shown). Further, the flow path inlet 22 a on the other end side in the gas introduction pipe 22 opens above the baffle plate 4 in the circulation space 8 (that is, on the downstream side). The outlet side of the gas introduction pipe 22 is connected to the hole 31h of the cylindrical portion 31 in the tangential direction. Thereby, blow-by gas is introduced along the inner peripheral surface of the cylindrical portion 31.

  As shown in FIG. 4, the gas outlet pipe 23 is an L-shaped circular pipe whose downstream side is bent forward, and communicates with the cyclone chamber S via a flow path inlet 23 a on one end side. Further, the flow path outlet 23 b on the other end side of the gas outlet pipe 23 is outside the cover member 2 that is outside the circulation space 8 via a PCV valve (check valve) 25 having a pipe line penetrating the cover member 2. (That is, communicates with the intake system side of the engine).

  A collection chamber R communicating with the cyclone chamber S is formed inside the oil collection box 24. As shown in FIG. 1, the oil collection box 24 is provided with a box lower part 41 located below and an upper part, and a rear surface side protruding rearward (side wall 7 side of the cylinder block 6) from the box lower part 41. And a box top 42 formed thereon. The box lower part 41 has a projecting part 43 projecting downward in a semicircular shape in a side view (viewed from the front and rear direction). The projecting part 43 includes a check valve 44 (see also FIG. 5). Is attached. The check valve 44 is attached to the rear surface side of the box lower portion 41, whereby the oil in the collection chamber R is discharged to the rear of the oil collection box 24.

  Thus, since the oil collection box 24 has the box upper part 42 protruded rearward, even when the check valve 44 is provided in the box lower part 41 to secure an oil discharge path, the collection chamber in the oil collection box 24 is provided. It becomes possible to secure the necessary capacity of R. Further, in the oil collection box 24, the check valve 44 is provided on the rear wall (the wall on the side wall 7 side of the cylinder block 6), so that the gas in the oil separator 1 (that is, the blow-by gas distribution space 8). An increase in the size in the distribution direction (vertical direction) can be suppressed.

  In the cyclone 3, oil particles having a relatively small diameter in the blow-by gas are introduced into the cyclone chamber S from the channel inlet 22 a of the gas introduction pipe 22. Thereafter, the oil particles move to the right (hollow conical portion 32 side) while swiveling between the outer peripheral surface 23c of the gas outlet tube 23 and the hole (inner peripheral surface) 31h of the cylindrical portion 31 shown in FIG. . Furthermore, the oil particles in the blow-by gas are guided to the collection chamber R of the oil collection box 24 while swirling in the hollow cone portion 32.

  Here, the oil particles from the hollow conical portion 32 are first guided into the box upper part 42 (the upper part of the collection chamber R), adhere to the inner wall, and then move downward along the wall surface due to gravity to finally reach the end. Therefore, it is stored in the box lower part 41 (lower part of the collection chamber R). The stored oil is discharged from the oil collection box 24 by opening the check valve 44 when the engine is stopped. The separated gas is led to the outside (engine intake system) through the gas outlet pipe 23. Further, part of the oil particles adheres to the side peripheral surfaces (holes 31h and 32h) of the cyclone chamber S due to centrifugal force at the time of swirling, and then moves downward along the side peripheral surfaces due to gravity. It is collected in the collection chamber R.

  As shown in FIG. 1, the baffle plate 4 extends substantially in the left-right direction from the right edge of the cover member 2 to the vicinity of the left edge below the mounting portion of the cyclone 3 in the cover member 2 (upstream side in the circulation space 8). Exists. As shown in FIG. 4, the baffle plate 4 is disposed so as to cover the entire lower surface of the cyclone 3 (at least the lower surfaces of the cyclone main body 21 and the oil collecting box 24). The front end (rear end) of the baffle plate 4 protrudes rearward from the rear surface 12 a of the flange portion 12.

  Further, a U-shaped portion 4a having a substantially U-shape when viewed from the side is formed at an intermediate portion in the left-right direction of the baffle plate 4. The upper surface (inner peripheral surface) of the U-shaped portion 4 a is formed along the lower surface in the state of being close to the lower surface (outer peripheral surface) of the protruding portion 43 in the box lower portion 41 of the oil collecting box 24. With such a configuration, a compact configuration in which the distance between the oil collection box 24 (the cyclone 3) and the baffle plate 4 is reduced can be realized. Further, the oil discharged from the check valve 44 of the oil collection box 24 can be guided in a predetermined direction (that is, the drain line side communicating with an oil pan (not shown)) by the U-shaped portion of the baffle plate.

  Between the left and right ends 4b, 4c of the baffle plate 4 and the left and right ends of the cover member 2 (more precisely, including the left and right ends of the lower recess 7b in the cylinder block 6 in FIG. 3) A gap is provided to facilitate flow in the direction. Moreover, as shown in FIG. 4, the U-shaped part 4a of the baffle plate 4 is formed so that the rear end side is notched and the rearward projecting length is smaller than other parts.

  As shown in FIG. 3, the oil separator 1 configured as described above is bolted to the cylinder block 6 so as to cover the openings of the upper and lower recesses 7 a and 7 b formed in the side wall 7 of the cylinder block 6. Thereby, a part of the side wall 7 of the cylinder block 6 (including the recesses 7a and 7b and the partition wall 9 partitioning between them) substantially constitutes a part of the oil separator 1. At this time, a part (rear part side) of the cyclone 3 is in a state of projecting into the upper recess 7a, and the tip of the baffle plate 4 is in a state of projecting into the lower recess 7b. In addition, although illustration is abbreviate | omitted, the recessed parts 7a and 7b are formed in the size corresponding to the internal space of the cover member 2, and the width of the left-right direction of the recessed parts 7a and 7b is the width of the internal space of the cover member 2. They are approximately the same size.

  In FIG. 3, an image of the flow of blow-by gas is shown by arrows. The blow-by gas is introduced into the circulation space 8 from the crankcase side (not shown) through the lower opening 10 of the lower recess 7b. Thereafter, the blow-by gas flows upward so as to bypass the baffle plate 4 protruding so as to block the upward flow from below. At this time, some of the oil particles in the blow-by gas are collected by adhering to the lower surface of the baffle plate 4.

  Here, like the baffle plate 4, the partition wall 9 formed on the side wall 7 of the cylinder block 6 protrudes so as to block the flow of blow-by gas from below to above, and the front edge of the partition wall 9 9a contacts the upper part of the rear surface 41a of the box lower part 41 of the oil collecting box 24 and the front end of the partition wall 14 (see FIG. 1) of the cover member 2. Accordingly, a part of the distribution space 8 is vertically partitioned by the partition wall 9. Further, a portion of the box upper part 42 that protrudes rearward from the box lower part 41 is located at the upper part of the partition wall 9.

  The blow-by gas after passing through the baffle plate 4 passes through the gap between the front end edge 9a (right side portion) of the partition wall 9 and the rear end of the partition wall 14b (see FIG. 1) of the cover member 2, and further upwards. Flowing. Due to such a flow of blow-by gas, relatively large oil particles are separated from the blow-by gas by stalling in a region where the flow velocity is reduced or colliding with the peripheral wall of the circulation space 8 or the like. Then, a blow-by gas containing oil particles having a relatively small diameter is introduced into the cyclone 3 from the flow path inlet 22a of the gas introduction pipe 22 that opens toward the rear (recess 7a side).

  As described above, the oil separator 1 collects oil particles having a relatively large diameter by the baffle plate 4 positioned on the upstream side of the circulation space 8 of the blow-by gas, and has a relatively small diameter (by the cyclone 3 positioned on the downstream side). Since oil particles of about 1 μm are collected, good collection efficiency can be achieved by including particles in a relatively small diameter oil. Further, there is an advantage that a compact configuration can be maintained without complicating the flow path in the distribution space 8. In particular, the outer peripheral surface of the oil collection box 24 and the like in the cyclone 3 attached to the rear surface side of the cover member 2 is part of the gas flow path in the circulation space 8 together with the partition walls 9, 14 a, 14 b and the baffle plate 4. Since it defines, the same effect as a labyrinth type separator is exhibited.

  Although the present invention has been described based on specific embodiments, these embodiments are merely examples, and the present invention is not limited to these embodiments. For example, the oil separator according to the present invention is not limited to the cylinder block described above, and may be installed so as to cover a part of an arbitrary wall in the internal combustion engine as long as it can be connected to at least a space through which blow-by gas flows. . The shape and arrangement of the baffle plate can be variously changed as long as it functions as a baffle plate that prevents the flow of gas in at least the flow space of the blow-by gas. Further, the baffle plate does not necessarily have to be attached to the cover member, and only the baffle plate protruding from the cylinder block side as in the partition wall 9 described above may be used. Note that all the components of the oil separator according to the present invention shown in the above-described embodiment are not necessarily essential, and can be appropriately selected as long as they do not depart from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Oil separator 2 Cover member 3 Cyclone 4 Baffle plate 4a U-shaped part 6 Cylinder block 7 Side wall 7a Recessed part 8 Distribution space 9 Partition wall 21 Cyclone main body 22 Gas introduction pipe 22a Channel inlet 23 Gas outlet pipe 23b Channel outlet 24 Oil Collection box 41 Box lower part 42 Box upper part 44 Check valve C Center axis R Collection room S Cyclone room

Claims (5)

An oil separator for separating oil in blow-by gas of an internal combustion engine,
A cover member attached to the side wall so as to cover a recess formed in a side wall of a cylinder block of the internal combustion engine , and forming a flow space for the blow-by gas in cooperation with the recess ;
A cyclone attached to the inside of the cover member to be placed in the circulation space;
A baffle plate protruding toward the circulation space so that a tip is located in the recess from the cover member to be disposed in the circulation space ;
The cyclone has a cyclone body having a cyclone chamber of cylindrical shape is formed therein, is connected to one end of the cyclone body, and the oil collection box collecting chamber communicating formed therein in the cyclone chamber, wherein A gas introduction pipe that is tangentially connected to an inner peripheral surface of the cyclone chamber with respect to the cyclone chamber and introduces the blow-by gas into the cyclone chamber; and the blow-by gas after separating the oil from the cyclone chamber to the outside a cyclone tangential inflow type which have a gas outlet pipe leading to,
The cyclone is arranged such that the cyclone main body is on the upper side, the oil collection box is on the lower side, and the center axis of the cyclone main body is inclined with respect to the gas flow direction in the flow space,
The flow path inlet of the gas introduction pipe opens to the downstream side of the baffle plate in the circulation space,
The oil separator according to claim 1, wherein a flow path outlet of the gas outlet pipe communicates with an outside of the cover member outside the circulation space by a pipe line penetrating the cover member. A partition wall projecting from the side wall of the cylinder block toward the circulation space, the partition wall dividing the recess into an upper recess and a lower recess communicating with each other; 2. The lower opening according to claim 1, further comprising a lower opening for introducing the blow-by gas into a lower recess, wherein the baffle plate is disposed upstream of the partition wall, and the cyclone is disposed downstream of the partition wall. Oil separator. The side wall of the cylinder block before Symbol oil collection box, oil separator according to claim 1 or 2, characterized in that the valve for discharging the oil from the oil collection box is provided. The oil separator according to claim 3 , wherein the baffle plate has a U-shaped portion disposed so as to cover a lower surface side of a portion where the valve is provided in the oil collecting box. The said oil collection box has the box lower part provided with the said valve, and the box upper part provided so that it might protrude from the box lower part to the side wall side of the said cylinder block , The Claim 3 or Claim characterized by the above-mentioned. 4. The oil separator according to 4 .

Images