Blow-by gas treatment device and engine having the blow-by gas treatment device

Abstract

The present invention provides a blow-by gas treatment device that can suppress the release of oil separated from blow-by gas from an outlet even when the engine tilts in the front-rear direction, and an engine having the blow-by gas treatment device. The blow-by gas treatment device (100) of the present invention includes: a main structural part (101) that separates oil (OL) from blow-by gas (BG); and an outlet part (40) that supplies the gas (G) separated from the blow-by gas (BG) to the intake system. The main structural part (101) includes: a first blow-by gas intake part (111); a second blow-by gas intake part (112); a separation part (330) that separates the blow-by gas (BG) into oil (OL) and gas (G); a first oil guiding part (151) that guides the oil (OL) forward; a second oil guiding part (152) that guides the oil (OL) backward; a first oil discharge port (161) that discharges the oil (OL) into the engine; and a second oil discharge port (162) that discharges the oil (OL) into the engine.

Description

Technical Field

[0001] The present invention relates to a blow-by gas treatment device and an engine having the blow-by gas treatment device. The blow-by gas treatment device is mounted on an internal combustion engine such as a diesel engine, separates blow-by gas into oil and gas, and supplies the gas to the intake system of the engine. Background Art

[0002] For example, a blow-by gas filter is provided inside the valve cover of a diesel engine. The blow-by gas filter separates blow-by gas into oil and gas such as unburned gas. However, in a normal diesel engine, it is sometimes impossible to clearly distinguish the oil discharge path and the gas discharge path.

[0003] A ventilation device for preventing oil from flowing out is disclosed in Patent Document 1. In the ventilation device described in Patent Document 1, a front ventilation chamber and a rear ventilation chamber are provided in the valve cover chamber, and a ventilation outlet is provided in the central portion. The ventilation outlet is connected to the front ventilation chamber and the rear ventilation chamber via a ventilation path. When the engine tilts forward or backward, even if oil invades the front ventilation chamber or the rear ventilation chamber, the ventilation device described in Patent Document 1 can prevent the oil from invading the part from either the front ventilation chamber or the rear ventilation chamber to the ventilation outlet. Therefore, the gas can be discharged from the front ventilation chamber and the rear ventilation chamber without accompanying the outflow of oil.

[0004] However, in the ventilation device described in Patent Document 1, the discharge path of the oil separated in the front ventilation chamber and the rear ventilation chamber is not clearly disclosed. That is, the discharge path of the oil separated in the front ventilation chamber and the rear ventilation chamber and the discharge path of the gas separated in the front ventilation chamber and the rear ventilation chamber are not clearly distinguished. Therefore, when the engine tilts in the front-rear direction, the oil separated from the blow-by gas sometimes cannot be sufficiently discharged and is released to the outside of the engine from the discharge port (outlet) of the blow-by gas treatment device. In this regard, there is room for improvement in the ventilation device described in Patent Document 1.

[0005] In addition, in a ventilation device such as that described in Patent Document 1, there is sometimes a case where an oil separation material such as glass wool provided in the ventilation chamber cannot completely separate the blow-by gas into oil and gas. For example, the oil contained in the blow-by gas is not completely separated from the blow-by gas by the oil separation material and may slightly pass through the oil separation material. Then, the oil that has passed through the oil separation material may stay in, for example, the ventilation path and the ventilation outlet described in Patent Document 1.

[0006] If oil remains in the ventilation path, ventilation outlet, etc., since the internal pressure in the ventilation path and ventilation outlet is relatively high, the retained oil may, for example, seep out from near the ventilation outlet to the outside of the engine.

[0007] Alternatively, if oil remains in the ventilation path, ventilation outlet, etc., the retained oil may mix with the water vapor contained in the blow-by gas to form an emulsion. When an emulsion is generated, the path of the blow-by gas such as the ventilation path and ventilation outlet may be blocked. If the path of the blow-by gas is blocked, the internal pressure of the engine rises, and for example, components such as the oil level gauge guide rod provided in the crankcase may be damaged. In addition, if the path of the blow-by gas is blocked, the internal pressure of the engine rises, and the turbocharger may suck in oil.

[0008] In this way, when the oil contained in the blow-by gas remains in the ventilation path, ventilation outlet, etc., adverse conditions such as oil seeping out to the outside of the engine and the path of the blow-by gas being blocked occur.

[0009] A mist separator is disclosed in Patent Document 2. The mist separator can improve the oil separation efficiency by discharging the scattered oil flowing into the gas flow path to the cam chamber side at a position far below the gas inlet. The mist separator described in Patent Document 2 separates oil from the blow-by gas flowing in the gas flow path.

[0010] Between the cylinder head cover and the baffle, a partitioned chamber and a first guide wall are provided for the gas flow path including the gas inlet. The first guide wall is above the gas inlet and the chamber, and extends obliquely downward toward the gas inlet and the chamber. On the baffle, a discharge hole for discharging the oil in the chamber is formed at the horizontal inner bottom of the chamber.

[0011] Thus, the scattered oil flowing into the gas flow path among the scattered oil flipped up by the rotation of the camshaft collides with the inclined first guide wall, is guided to the chamber through the transmission of the first guide wall, and then the scattered oil in the chamber passes through the discharge hole of the chamber and is discharged to the cam chamber side at a position far below the gas inlet, thereby improving the oil separation efficiency.

[0012] However, in the mist separator described in Patent Document 2, the discharge hole is formed at the horizontal inner bottom of the chamber. Therefore, although there is a discharge hole, the inner bottom of the chamber is parallel to the installation surface (such as a horizontal plane) on which the vehicle equipped with the engine is placed. Therefore, even if the discharge hole is formed on the horizontal inner bottom surface, scattered oil may remain at the horizontal inner bottom of the chamber.

[0013] The scattered oil contains moisture (water vapor). Therefore, the moisture contained in the retained scattered oil sometimes condenses on the horizontal inner bottom of the chamber at low temperatures. When the moisture contained in the retained scattered oil condenses, it sometimes clogs the horizontal inner bottom surface and the discharge holes of the chamber. As a result, the scattered oil in the chamber cannot pass through the discharge holes formed in the horizontal inner bottom and cannot be discharged toward the cam chamber side at a position far from directly below the gas inlet. In this regard, there is room for improvement in the oil mist separator described in Patent Document 2.

[0014] Patent Document 3 discloses an oil mist separator that separates oil mist from blow-by gas in an internal combustion engine. The separator unit disposed in the oil mist separator described in Patent Document 3 is composed of a synthetic resin porous plate formed with throttle holes for increasing the flow rate of the blow-by gas, a synthetic resin rear frame having a collision plate for receiving the blow-by gas that has become a high-speed flow, and a fibrous material that overlaps the collision plate for improving the oil separation performance.

[0015] In Patent Document 3, as the fibrous material, for example, polyester fiber, acrylic fiber, aramid fiber, PPS (polyphenylene sulfide) fiber, etc. can be cited. In addition, as the form of the fibrous material, fabrics such as non-woven fabric and fleece can be cited. Moreover, the fibrous material described in Patent Document 3 is compressed and held between the leg portion and the collision plate at an appropriate compression rate by being pressed against the leg portion provided on the porous plate.

[0016] Here, considering prevention of detachment and improvement of holding performance, a filter or element for improving the oil separation performance such as the fibrous material described in Patent Document 3 is preferably held using a fastening member such as a bolt coated with an adhesive. However, the filter and element are formed of, for example, the aforementioned fibers, glass wool, steel wool, etc. Therefore, when using a fastening member to hold the filter and element, the amount of deformation of the filter and element varies depending on the torque of the fastening member. As a result, the shape of the filter and element is unstable. Thus, when using a fastening member to hold the filter and element, there is a problem that the oil separation performance is unstable.

[0017] Prior Art Documents

[0018] Patent Documents

[0019] Patent Document 1: Japanese Utility Model Laid-Open No. 6-53709

[0020] Patent Document 2: Japanese Patent Laid-Open No. 2018-119474

[0021] Patent Document 3: Japanese Patent Laid-Open No. 2016-114035 Summary of the Invention

[0022] Problems to be Solved by the Invention

[0023] The present invention has been completed in view of the above problems, and an object thereof is to provide a blow-by gas treatment device that can suppress oil separated from blow-by gas from being released from an outlet even when an engine is tilted in the front-rear direction, and an engine having the blow-by gas treatment device.

[0024] Alternatively, an object is to provide a blow-by gas treatment device that can suppress oil contained in blow-by gas from staying in an outlet portion, and an engine having the blow-by gas treatment device.

[0025] Alternatively, an object is to provide a blow-by gas treatment device that can suppress oil contained in blow-by gas from staying and suppress condensation of moisture contained in the oil at low temperatures, and an engine having the blow-by gas treatment device.

[0026] Alternatively, an object is to provide a blow-by gas treatment device that can achieve stable oil separation performance when a filter is held using fastening members, and an engine having the blow-by gas treatment device.

[0027] Technical Means for Solving the Problems

[0028] The above-mentioned problem to be solved is solved by the blow-by gas treatment device of the present invention. A blow-by gas treatment device for treating blow-by gas generated in an engine, characterized in that it has: a main structural part which is arranged in the hood of the engine, takes in and guides the blow-by gas, and separates the oil contained in the blow-by gas from the blow-by gas; and an outlet part which supplies the gas, that is, the gas introduced from the main structural part after the oil is separated from the blow-by gas by the main structural part, to the intake system of the engine. The main structural part has: a first blow-by gas intake part which is arranged on the front side of the engine and is used for taking in the blow-by gas; a second blow-by gas intake part which is arranged on the rear side of the engine and is used for taking in the blow-by gas; a separation part which is arranged between the first blow-by gas intake part and the second blow-by gas intake part in the front-rear direction of the engine and separates the blow-by gas taken in by the first blow-by gas intake part and the second blow-by gas intake part into the oil and the gas; a first oil guiding part which is arranged from the separation part towards the front side and guides the oil separated from the blow-by gas by the separation part towards the front side; a second oil guiding part which is arranged from the separation part towards the rear side and guides the oil separated from the blow-by gas by the separation part towards the rear side; a first oil drain port which is arranged on the front side, temporarily stores the oil guided by the first oil guiding part and discharges it into the engine; and a second oil drain port which is arranged on the rear side, temporarily stores the oil guided by the second oil guiding part and discharges it into the engine.

[0029] According to the blow-by gas treatment device of the present invention, the main structural part of the blow-by gas treatment device has a first oil guiding part, a second oil guiding part, a first oil drain port, and a second oil drain port. The first oil guiding part is arranged forward from the separation part that separates the blow-by gas into oil and gas, and guides the oil separated from the blow-by gas by the separation part to the front side of the engine. The second oil guiding part is arranged backward from the separation part that separates the blow-by gas into oil and gas, and guides the oil separated from the blow-by gas by the separation part to the rear side of the engine. The first oil drain port is arranged on the front side of the engine, temporarily stores the oil guided by the first oil guiding part and discharges it into the engine. The second oil drain port is arranged on the rear side of the engine, temporarily stores the oil guided by the second oil guiding part and discharges it into the engine. In this way, the oil separated from the blow-by gas by the separation part is guided to the front side of the engine by the first oil guiding part, and after being temporarily stored in the first oil drain port, it is discharged into the engine. In addition, the oil separated from the blow-by gas by the separation part is guided to the rear side of the engine by the second oil guiding part, and after being temporarily stored in the second oil drain port, it is discharged into the engine. Therefore, in the blow-by gas treatment device of the present invention, the discharge path of the oil separated from the blow-by gas by the separation part is clear. In addition, the gas after separating the oil from the blow-by gas by the main structural part is led out to the outlet part of the blow-by gas treatment device through the main structural part. Then, the outlet part of the blow-by gas treatment device supplies the gas introduced through the main structural part to the intake system of the engine. In this way, in the blow-by gas treatment device of the present invention, the discharge path of the oil separated from the blow-by gas by the separation part and the discharge path of the gas separated from the blow-by gas by the separation part are clearly distinguished. Thus, even if the engine tilts in the front-rear direction, it is possible to suppress the oil separated from the blow-by gas from being released from the outlet part.

[0030] In the blow-by gas treatment device of the present invention, preferably, it is characterized in that the separation part is arranged at the central part between the first oil drain port and the second oil drain port in the front-rear direction.

[0031] According to the blow-by gas treatment device of the present invention, the separation part that separates the blow-by gas into oil and gas is arranged at the central part between the first oil drain port that temporarily stores the oil guided by the first oil guiding part and discharges it into the engine and the second oil drain port that temporarily stores the oil guided by the second oil guiding part and discharges it into the engine. In this way, the separation part is arranged at a position farther from the first oil drain port and the second oil drain port. Therefore, even if the engine tilts in the front-rear direction, it is possible to suppress the oil temporarily stored in the first oil drain port and the second oil drain port, the oil and oil mist existing above the first oil drain port and the second oil drain port from being involved in the gas separated from the blow-by gas by the separation part or being remixed. Thus, even if the engine tilts in the front-rear direction, it is possible to further suppress the oil separated from the blow-by gas from being released from the outlet part.

[0032] In addition, since it is possible to suppress the oil and oil mist from being involved in the gas separated from the blow-by gas by the separation unit or remixed, it is possible to suppress the oil separated from the blow-by gas from being released from the outlet unit regardless of the position of the outlet unit. As a result, the degree of freedom in selecting the installation position and installation direction of the outlet unit can be increased.

[0033] In the blow-by gas treatment device of the present invention, preferably, it is characterized in that the first oil guiding portion and the second oil guiding portion are in a groove shape.

[0034] According to the blow-by gas treatment device of the present invention, by forming the first oil guiding portion and the second oil guiding portion in a groove shape, a simple structure can be achieved, and moreover, even when the engine is tilted in the front-rear direction, the oil separated from the blow-by gas by the separation unit can be reliably guided to the front side and the rear side of the engine.

[0035] In the blow-by gas treatment device of the present invention, preferably, it is characterized in that the main structural portion has a partition wall portion horizontally disposed along the front-rear direction, the first blow-by gas intake portion and the second blow-by gas intake portion are provided on the lower surface side of the partition wall portion, and the first oil guiding portion and the second oil guiding portion are provided on the upper surface side of the partition wall portion.

[0036] According to the blow-by gas treatment device of the present invention, the first blow-by gas intake portion and the second blow-by gas intake portion for taking in the blow-by gas and the first oil guiding portion and the second oil guiding portion for guiding the oil are separately provided on both the upper surface side and the lower surface side via a common partition wall portion. Therefore, the first blow-by gas intake portion, the second blow-by gas intake portion, the first oil guiding portion, and the second oil guiding portion can be provided on the partition wall portion as a single member. Therefore, the size of the blow-by gas treatment device in the up-down direction can be suppressed. Therefore, the height dimension of the cover in which the blow-by gas treatment device is disposed can be suppressed, and the height dimension of the engine in which the cover has the blow-by gas treatment device can be suppressed.

[0037] In the blow-by gas treatment device of the present invention, preferably, it is characterized in that the separation unit has: a flow velocity increasing operation unit that increases the flow velocity of the blow-by gas in the vertical direction; a filter for the blow-by gas whose flow velocity has been increased by the flow velocity increasing operation unit; and a collision plate that extends in the horizontal direction, causes the blow-by gas that has passed through the filter to collide, and separates it into the oil and the gas.

[0038] In the blow-by gas treatment device according to the present invention, after the flow rate of the blow-by gas is increased by the flow rate increasing operation unit, the blow-by gas collides with the collision plate through the filter. Therefore, the blow-by gas is more reliably separated into oil and the gas from which the oil mist has been removed. In addition, the flow rate increasing operation unit is located at the central position in the front-rear direction of the engine, and causes the flow rate of the blow-by gas to rise along the vertical direction (up and down direction). In addition, the collision plate extends in the horizontal direction and causes the blow-by gas that has passed through the filter to collide. Therefore, compared with the case where the flow rate increasing operation unit causes the flow rate of the blow-by gas to rise along the horizontal direction and causes the blow-by gas to collide with the collision plate extending in the vertical direction, the vertical dimension of the blow-by gas treatment device can be suppressed.

[0039] The above-mentioned problem to be solved is solved by the blow-by gas treatment device of the present invention. A blow-by gas treatment device for treating blow-by gas generated in an engine, characterized by comprising: a separation unit disposed in a hood of the engine, separating the blow-by gas taken in from a blow-by gas intake unit into oil and gas; and an outlet unit supplying the gas, which is the gas separated from the blow-by gas by the separation unit and introduced from the separation unit, to an intake system of the engine. The outlet unit has an oil guiding surface for guiding the oil remaining in the gas separated from the blow-by gas into the hood.

[0040] In the blow-by gas treatment device according to the present invention, the outlet unit has an oil guiding surface for guiding the oil remaining in the gas separated from the blow-by gas into the hood. Thus, even when there is oil remaining in the gas separated from the blow-by gas by the separation unit, the blow-by gas treatment device of the present invention can suppress the oil contained in the blow-by gas from staying in the outlet unit.

[0041] In the blow-by gas treatment device of the present invention, preferably, the outlet unit includes: an outlet mounting part disposed on an upper part of the hood, having a through hole through which the gas passes; and a container body disposed on the outlet mounting part, temporarily accommodating the gas that has passed through the through hole, and supplying the gas to the intake system. The oil guiding surface is an oil guiding inclined surface that slopes downward from a mating surface between the outlet mounting part and the container body toward the through hole.

[0042] In the blow-by gas treatment device according to the present invention, the oil guiding surface is an oil guiding inclined surface that slopes downward from a mating surface between the outlet mounting part and the container body toward the through hole. Therefore, the oil remaining in the gas separated from the blow-by gas by the separation unit flows downward toward the through hole along the oil guiding inclined surface, passes through the through hole, and is reliably guided into the hood. Thus, the blow-by gas treatment device of the present invention can more reliably suppress the oil contained in the blow-by gas from staying in the outlet unit.

[0043] In the gas leakage treatment device of the present invention, preferably, it is characterized in that the oil guiding inclined surface is formed in the entire area from the mating surface to the inner surface of the through hole.

[0044] In the gas leakage treatment device according to the present invention, the oil guiding inclined surface is formed in the entire area from the mating surface between the outlet mounting portion and the container body to the inner surface of the through hole. Therefore, it is possible to suppress the oil remaining in the gas separated from the gas leakage by the separation portion from being caught or staying in at least a part of the outlet portion, and to flow smoothly downward toward the through hole along the oil guiding inclined surface. Then, the oil flowing along the oil guiding inclined surface toward the through hole passes through the through hole and is more reliably guided into the cover. Thus, the gas leakage treatment device of the present invention can more reliably suppress the oil contained in the gas leakage from staying in the outlet portion.

[0045] In the gas leakage treatment device of the present invention, preferably, it is characterized in that the oil guiding inclined surface is a part of the surface of a cone.

[0046] In the gas leakage treatment device according to the present invention, since the oil guiding inclined surface is a part of the surface of a cone, the oil remaining in the gas separated from the gas leakage by the separation portion can flow smoothly downward toward the through hole along the oil guiding inclined surface.

[0047] The gas leakage treatment device of the present invention, preferably, is further provided with: a guiding wall portion provided in the cover for guiding the gas separated from the gas leakage to the outlet portion; and an oil guiding portion for guiding the oil separated from the gas leakage by the separation portion to an oil drain port. The oil guided from the outlet portion into the cover by the oil guiding surface flows through the guiding wall portion and is introduced into the oil guiding portion.

[0048] In the gas leakage treatment device according to the present invention, the oil guided from the outlet portion into the cover by the oil guiding surface flows through the guiding wall portion and is introduced into the oil guiding portion. The oil guiding portion can guide the oil separated from the gas leakage by the separation portion to the oil drain port, and can also guide the oil guided from the outlet portion into the cover by the oil guiding surface to the oil drain port. Thus, the oil separated from the gas leakage is recovered, for example, in an oil pan or an oil container provided in an engine, and is suppressed from being released from the outlet portion.

[0049] The above-mentioned problem to be solved is solved by the blow-by gas treatment device of the present invention. A blow-by gas treatment device for treating blow-by gas generated in an engine, characterized by having: a separation unit that separates the blow-by gas taken in from the blow-by gas intake unit into oil and gas; and an oil guiding unit that guides the oil separated from the blow-by gas by the separation unit. The separation unit is arranged to be inclined in a direction in which the oil separated from the blow-by gas by the separation unit is introduced into the oil guiding unit.

[0050] According to the blow-by gas treatment device of the present invention, the separation unit is arranged to be inclined in a direction in which the oil separated from the blow-by gas by the separation unit is introduced into the oil guiding unit. Therefore, the oil separated from the blow-by gas by the separation unit does not stay in the separation unit but is introduced into the oil guiding unit. Thus, the blow-by gas treatment device of the present invention can suppress the retention of the oil contained in the blow-by gas and can suppress the condensation of the moisture contained in the oil at low temperatures. Thereby, the operation of separating the blow-by gas into oil and gas by the separation unit is performed more reliably.

[0051] In the blow-by gas treatment device of the present invention, preferably, the separation unit has: a flow velocity increasing operation unit that causes the flow velocity of the blow-by gas to increase along a direction inclined with respect to the vertical direction; a filter for passing the blow-by gas whose flow velocity has been increased by the flow velocity increasing operation unit; and a collision plate that causes the blow-by gas that has passed through the filter to collide and separates it into the oil and the gas. The surface of the flow velocity increasing operation unit facing the collision plate is inclined downward toward the oil guiding unit.

[0052] According to the blow-by gas treatment device of the present invention, the flow velocity increasing operation unit causes the flow velocity of the blow-by gas to increase along a direction inclined with respect to the vertical direction (up and down direction) and causes the blow-by gas to collide with the collision plate. Thereby, the blow-by gas is reliably separated into oil and gas. Then, in the collision plate, the oil separated from the blow-by gas passes through the filter and falls onto the surface of the flow velocity increasing operation unit facing the collision plate. Here, the surface of the flow velocity increasing operation unit is inclined downward toward the oil guiding unit. Therefore, the oil that has fallen onto the surface of the flow velocity increasing operation unit flows on the surface of the flow velocity increasing operation unit due to its own weight and is introduced into the oil guiding unit. Thus, the blow-by gas treatment device of the present invention can more reliably suppress the retention of the oil contained in the blow-by gas and can more reliably suppress the condensation of the moisture contained in the oil at low temperatures.

[0053] The gas leakage treatment device of the present invention preferably further comprises: a setting portion on which the filter and the collision plate are placed, for inclining the filter and the collision plate downward toward the oil guiding portion; the flow velocity increasing operation portion has a throttle hole through which the gas leakage passes and is supplied to the filter, and the axis of the throttle hole extends along a direction inclined with respect to the vertical direction and is orthogonal to the inner surface of the collision plate.

[0054] In the gas leakage treatment device according to the present invention, a setting portion provided with a filter and a collision plate is further arranged. The setting portion inclines the filter and the collision plate downward toward the oil guiding portion. In addition, the flow velocity increasing operation portion has a throttle hole through which the gas leakage passes and is supplied to the filter. Moreover, the axis of the throttle hole is orthogonal to the inner surface of the collision plate. Therefore, the gas leakage after the flow velocity increases through the throttle hole of the flow velocity increasing operation portion collides perpendicularly with the inner surface of the collision plate. Thus, the gas leakage withstands a strong impact force from the collision plate and is reliably separated into oil and gas. Then, since the axis of the throttle hole extends along a direction inclined with respect to the vertical direction, the oil separated from the gas leakage in the collision plate falls onto the surface of the flow velocity increasing operation portion in a direction different from the flow direction of the gas leakage colliding with the inner surface of the collision plate (i.e., the vertical direction). Therefore, it is possible to suppress the oil separated from the gas leakage in the collision plate from entering the throttle hole and suppress the blockage of the throttle hole. Thus, the action of making the gas leakage collide with the collision plate and separating it into oil and gas is performed more reliably.

[0055] In the gas leakage treatment device of the present invention, preferably, the flow velocity increasing operation portion has a plurality of the throttle holes, and the plurality of throttle holes are arranged at staggered positions in a direction intersecting with the inclination direction of the surface of the flow velocity increasing operation portion.

[0056] In the gas leakage treatment device according to the present invention, it is possible to suppress the oil introduced along the inclination direction of the surface of the flow velocity increasing operation portion into the oil guiding portion, for example, from entering the throttle hole on the downstream side among the plurality of throttle holes, and suppress the blockage of the throttle hole on the downstream side. Thus, the action of making the gas leakage collide with the collision plate and separating it into oil and gas can be performed more reliably.

[0057] In the gas leakage treatment device of the present invention, preferably, the setting portion protrudes outward from the surface of the flow velocity increasing operation portion, forming an oil guiding gap region as the space between the flow velocity increasing operation portion and the filter, and the oil separated from the gas leakage by the separation portion flows along the surface of the flow velocity increasing operation portion in the oil guiding gap region.

[0058] In the gas leakage treatment device according to the present invention, the setting portion carrying the filter protrudes outward from the surface of the flow velocity increasing operation portion, forming an oil guiding gap region as the space between the flow velocity increasing operation portion and the filter. Then, the oil separated from the gas leakage by the separation portion flows along the surface of the flow velocity increasing operation portion in the oil guiding gap region. Thereby, it is possible to more reliably suppress the oil separated from the gas leakage from staying on the surface of the flow velocity increasing operation portion, and the oil separated from the gas leakage is more reliably introduced from the oil guiding gap region formed between the flow velocity increasing operation portion and the filter toward the oil guiding portion.

[0059] The gas leakage treatment device of the present invention preferably further comprises: an oil outlet inclined guiding portion that connects the surface of the flow velocity increasing operation portion and the oil guiding portion and inclines downward from the surface of the flow velocity increasing operation portion toward the oil guiding portion, and guides the oil flowing along the surface of the flow velocity increasing operation portion into the oil guiding portion, and the inclination angle of the oil outlet inclined guiding portion with respect to the horizontal plane is greater than the inclination angle of the surface of the flow velocity increasing operation portion with respect to the horizontal plane.

[0060] In the gas leakage treatment device according to the present invention, an oil outlet inclined guiding portion is further provided. The oil outlet inclined guiding portion connects the surface of the flow velocity increasing operation portion and the oil guiding portion and inclines downward from the surface of the flow velocity increasing operation portion toward the oil guiding portion. Then, the oil outlet inclined guiding portion guides the oil flowing along the surface of the flow velocity increasing operation portion into the oil guiding portion. Here, the inclination angle of the oil outlet inclined guiding portion with respect to the horizontal plane is greater than the inclination angle of the surface of the flow velocity increasing operation portion with respect to the horizontal plane. Thereby, the oil outlet inclined guiding portion can quickly guide the oil separated from the gas leakage by the separation portion and flowing along the surface of the flow velocity increasing operation portion into the oil guiding portion. In addition, it is possible to suppress the oil from staying near the surface of the flow velocity increasing operation portion, and it is possible to suppress the oil separated from the gas leakage by the separation portion from mixing into the gas leakage again.

[0061] The gas leakage treatment device of the present invention preferably further comprises: an oil inclined guiding return portion that is provided on the side opposite to the oil outlet inclined guiding portion when viewed from the oil guiding portion and is formed to incline from the lowermost portion of the oil outlet inclined guiding portion in a manner having an inclination opposite to that of the oil outlet inclined guiding portion.

[0062] The blow-by gas treatment device according to the present invention is further provided with an oil inclined guiding and returning part. When observed from the oil guiding part, the oil inclined guiding and returning part is arranged on the side opposite to the oil outlet inclined guiding part. In addition, the oil inclined guiding and returning part is formed obliquely from the lowermost part of the oil outlet inclined guiding part in a manner having an inclination opposite to the inclination of the oil outlet inclined guiding part. Therefore, when the oil separated from the blow-by gas by the separation part flows through the oil outlet inclined guiding part from the surface of the flow velocity increasing operation part, in order to suppress the outflow from the oil outlet inclined guiding part and the oil guiding part due to the flow trend of the oil during flow, the oil inclined guiding and returning part can temporarily store the oil. Then, the oil inclined guiding and returning part guides the oil to the oil guiding part and returns it.

[0063] In the blow-by gas treatment device of the present invention, preferably, it is characterized in that, in the extending direction of the oil guiding part, the length of the oil inclined guiding and returning part is longer than the length of the oil outlet inclined guiding part.

[0064] Even when the oil separated from the blow-by gas by the separation part flows through the oil outlet inclined guiding part from the surface of the flow velocity increasing operation part, the oil inclined guiding and returning part of the blow-by gas treatment device according to the present invention can suppress the overflow of the flowing oil, and can flow to and return to the oil guiding part after sufficiently accommodating the oil.

[0065] The above-mentioned problem to be solved is solved by the blow-by gas treatment device of the present invention. A blow-by gas treatment device for treating blow-by gas generated in an engine, characterized by comprising: a separation part that separates the blow-by gas taken in from a blow-by gas intake part into oil and gas, the separation part having: a flow velocity increasing operation part that increases the flow velocity of the blow-by gas; a filter for passing the blow-by gas whose flow velocity has been increased by the flow velocity increasing operation part; a collision plate that causes the blow-by gas that has passed through the filter to collide and separates it into the oil and the gas; a fastening member that is fastened to the flow velocity increasing operation part and holds the filter between the flow velocity increasing operation part and the collision plate; and a deformation suppressing member that is arranged between the flow velocity increasing operation part and the collision plate and suppresses the deformation of the filter due to the fastening of the fastening member.

[0066] In the gas leakage treatment device according to the present invention, the filter of the separation unit that separates the gas leakage into oil and gas is fastened to the flow velocity increasing operation unit by a fastening member, and thus is held between the flow velocity increasing operation unit and the collision plate. Here, a deformation suppressing member is disposed between the flow velocity increasing operation unit and the collision plate. The deformation suppressing member suppresses the deformation of the filter held between the flow velocity increasing operation unit and the collision plate due to the fastening of the fastening member. Thereby, when the filter is held using the fastening member, the deformation of the filter can be suppressed. For example, it is possible to suppress the difference in the amount of deformation of the filter due to the torque of the fastening member and the instability of the shape of the filter. Thereby, when the filter is held using the fastening member, stable oil separation performance can be achieved.

[0067] In the gas leakage treatment device according to the present invention, preferably, the fastening member has: a shaft portion fastened to the flow velocity increasing operation unit; and a head portion provided at one end of the shaft portion, and the deformation suppressing member is a cylindrical member having a hole through which the shaft portion passes, and is disposed between the flow velocity increasing operation unit and the head portion in a state where the shaft portion has passed through the hole.

[0068] In the gas leakage treatment device according to the present invention, the deformation suppressing member is a cylindrical member having a hole through which the shaft portion of the fastening member passes. Then, the deformation suppressing member is disposed between the flow velocity increasing operation unit and the head portion of the fastening member in a state where the shaft portion of the fastening member has passed through the hole of the deformation suppressing member. Therefore, the deformation suppressing member can withstand the force transmitted from the flow velocity increasing operation unit and the head portion of the fastening member due to the fastening of the fastening member between the flow velocity increasing operation unit and the head portion of the fastening member. Therefore, the deformation suppressing member can more reliably suppress the deformation of the filter held between the flow velocity increasing operation unit and the collision plate due to the fastening of the fastening member. Thereby, when the filter is held using the fastening member, stable oil separation performance can be more reliably achieved.

[0069] In the gas leakage treatment device according to the present invention, preferably, the deformation suppressing member uses the end portion of the cylindrical member to withstand the force transmitted from the head portion via the collision plate and the force transmitted from the flow velocity increasing operation unit due to the fastening of the fastening member.

[0070] In the gas leakage treatment device according to the present invention, the deformation suppression member uses the end portion of the cylindrical member to bear the force transmitted from the head of the fastening member via the collision plate due to the fastening of the fastening member and the force transmitted from the flow rate increasing operation portion. Therefore, the deformation suppression member can use the end portion to bear the force transmitted from the head of the fastening member, that is, the force that is made relatively uniform via the collision plate. Therefore, the deformation suppression member can more reliably suppress the deformation of the filter held between the flow rate increasing operation portion and the collision plate due to the fastening of the fastening member. Thus, when the filter is held by the fastening member, stable oil separation performance can be more reliably achieved.

[0071] In the gas leakage treatment device of the present invention, preferably, it is characterized in that the length of the deformation suppression member in the direction of the axis of the hole is equal to the thickness of the filter.

[0072] In the gas leakage treatment device of the present invention, the length of the deformation suppression member in the axial direction of the hole of the deformation suppression member is equal to the thickness of the filter. Therefore, the deformation suppression member can suppress the filter from being flattened to a length shorter than the length of the deformation suppression member in the axial direction of the hole. Therefore, the difference in the amount of deformation of the filter due to the torque of the fastening member can be more reliably suppressed. Thus, when the filter is held by the fastening member, stable oil separation performance can be achieved.

[0073] The above-mentioned problem to be solved is solved by the engine of the present invention having any of the above gas leakage treatment devices.

[0074] An engine equipped with the blow-by gas treatment device of the present invention has a main structural part of the blow-by gas treatment device including a first oil guiding part, a second oil guiding part, a first oil drain port, and a second oil drain port. The first oil guiding part is arranged forward from the separation part that separates blow-by gas into oil and gas, and guides the oil separated from the blow-by gas by the separation part to the front side of the engine. The second oil guiding part is arranged rearward from the separation part that separates blow-by gas into oil and gas, and guides the oil separated from the blow-by gas by the separation part to the rear side of the engine. The first oil drain port is provided on the front side of the engine, temporarily stores the oil guided by the first oil guiding part and discharges it into the engine. The second oil drain port is provided on the rear side of the engine, temporarily stores the oil guided by the second oil guiding part and discharges it into the engine. In this way, the oil separated from the blow-by gas by the separation part is guided to the front side of the engine by the first oil guiding part, discharged into the engine after being temporarily stored in the first oil drain port. In addition, the oil separated from the blow-by gas by the separation part is guided to the rear side of the engine by the second oil guiding part, discharged into the engine after being temporarily stored in the second oil drain port. Therefore, in the engine equipped with the blow-by gas treatment device of the present invention, the discharge path of the oil separated from the blow-by gas by the separation part is clear. In addition, the gas after separating the oil from the blow-by gas by the main structural part is led out to the outlet part of the blow-by gas treatment device through the main structural part. Then, the outlet part of the blow-by gas treatment device supplies the gas introduced through the main structural part to the intake system of the engine. In this way, in the engine equipped with the blow-by gas treatment device of the present invention, the discharge path of the oil separated from the blow-by gas by the separation part and the discharge path of the gas separated from the blow-by gas by the separation part are clearly distinguished. Thereby, even when the engine tilts in the front-rear direction, it is possible to suppress the oil separated from the blow-by gas from being released from the outlet part.

[0075] In the engine according to the present invention, the outlet part of the blow-by gas treatment device has an oil guiding surface for guiding the oil remaining in the gas separated from the blow-by gas into the cover. Thereby, even when there is oil remaining in the gas separated from the blow-by gas by the separation part, the engine of the present invention can suppress the oil contained in the blow-by gas from staying in the outlet part.

[0076] In the engine according to the present invention, the separation part of the blow-by gas treatment device is arranged inclined in the direction of guiding the oil separated from the blow-by gas by the separation part into the oil guiding part. Therefore, the oil separated from the blow-by gas by the separation part does not stay in the separation part but is introduced into the oil guiding part. Thereby, the engine of the present invention can suppress the retention of the oil contained in the blow-by gas and can suppress the condensation of the moisture contained in the oil at low temperatures. Thus, the operation of separating the blow-by gas into oil and gas by the separation part is performed more reliably.

[0077] In the engine according to the present invention, a filter of a separation unit that separates blow-by gas into oil and gas is fastened to a flow velocity increasing operation unit by a fastening member, and thus is held between the flow velocity increasing operation unit and a collision plate. Here, a deformation suppressing member is disposed between the flow velocity increasing operation unit and the collision plate. The deformation suppressing member suppresses deformation of the filter held between the flow velocity increasing operation unit and the collision plate due to the fastening of the fastening member. Thereby, when the filter is held by the fastening member, deformation of the filter can be suppressed. For example, it is possible to suppress the amount of deformation of the filter from varying due to the torque of the fastening member and the shape of the filter from becoming unstable. Thereby, when the filter is held by the fastening member, stable oil separation performance can be achieved.

[0078] Advantages of the Invention

[0079] According to the present invention, it is possible to provide a blow-by gas treatment device that can suppress oil separated from blow-by gas from being released from an outlet even when the engine tilts in the front-rear direction, and an engine having the blow-by gas treatment device.

[0080] Alternatively, according to the present invention, it is possible to provide a blow-by gas treatment device that can suppress oil contained in blow-by gas from staying in an outlet portion, and an engine having the blow-by gas treatment device.

[0081] Alternatively, according to the present invention, it is possible to provide a blow-by gas treatment device that can suppress retention of oil when separating blow-by gas into oil and gas and suppress condensation of moisture contained in the oil at low temperatures, and an engine having the blow-by gas treatment device.

[0082] Alternatively, according to the present invention, it is possible to provide a blow-by gas treatment device that can achieve stable oil separation performance when using a fastening member to hold a filter, and an engine having the blow-by gas treatment device. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 is a cross-sectional view of an engine having a blow-by gas treatment device according to an embodiment of the present invention.

[0084] Figure 2 is a cross-sectional view of the X-Z plane showing a structural example of the blow-by gas treatment device of the present embodiment.

[0085] Figure 3 is a perspective view of a structure having a cross-section of the X-Z plane showing a structural example of the blow-by gas treatment device of the present embodiment.

[0086] Figure 4 is a cross-sectional view of the X-Z plane showing a structural example of the blow-by gas treatment device of the present embodiment.

[0087] Figure 5It is a perspective view showing a structural example of the outlet portion of the blow-by gas treatment device according to the present embodiment.

[0088] Figure 6 It is a cross-sectional view showing Figure 5 the cross-section A-A along.

[0089] Figure 7 It is a cross-sectional view of the X-Z plane showing a structural example of the blow-by gas treatment device according to the present embodiment.

[0090] Figure 8 It is a perspective view showing a structural example of the separation portion of the blow-by gas treatment device according to the present embodiment and its peripheral area.

[0091] Figure 9 It is Figure 8 a cross-sectional view of the D-D line along the Y direction of the separation portion of the blow-by gas treatment device according to the present embodiment shown in

[0092] Figure 10 It is a perspective view showing the separation portion of the blow-by gas treatment device according to the present embodiment.

[0093] Figure 11 It is Figure 10 a cross-sectional view of the cross-section B-B shown in Detailed Embodiment

[0094] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0095] It should be noted that the embodiments described below are only preferred specific examples of the present invention. Although various technically preferred limitations are attached, the scope of the present invention is not intended to be limited to these embodiments. In addition, in each drawing, the same components are given the same reference numerals and detailed descriptions are omitted.

[0096] (Outline of Engine 1)

[0097] Figure 1 It is a cross-sectional view showing an engine having a blow-by gas treatment device according to the first embodiment of the present invention.

[0098] Figure 1 The engine 1 shown is an internal combustion engine, for example, an industrial diesel engine. The engine 1 is, for example, a multi-cylinder engine such as a supercharged high-power three-cylinder engine or four-cylinder engine with a turbocharger. The engine 1 is mounted on vehicles such as construction machinery, agricultural machinery, and lawn mowers.

[0099] (Structural Example of Engine 1)

[0100] The engine 1 has: a cylinder block 2, a cylinder head 3, a valve cover 4, an oil pan 7, and a blow-by gas treatment device 100. The cylinder head 3 is mounted on the cylinder block 2. The valve cover 4 is mounted on the cylinder head 3. The cylinder block 2 has cylinders 5 in the upper part and a crankcase 6 in the lower part. The oil pan 7 is disposed in the lower part of the crankcase 6. A piston 8 is disposed in the cylinder 5. A crankshaft 9 is disposed in the crankcase 6. The piston 8 is connected to the crankshaft 9 via a connecting rod 10.

[0101] As Figure 1 shown, the cylinder 5 has a valve cam chamber 11. A valve camshaft 12 is accommodated in the valve cam chamber 11. A tappet 13 can move up and down along a tappet guide hole 14. The lower part of the tappet 13 is mounted on the valve camshaft 12. A push rod 15 passes through an insertion hole 16. A rocker arm 17 is disposed in the valve cover 4. The upper end of the push rod 15 abuts against the rocker arm 17.

[0102] The rocker arm 17 is biased by a spring 18 toward the upper end of the push rod 15. The intake valve 19 and the exhaust valve 20 move up and down by the power transmitted via the push rod 15 and the rocker arm 17 under the rotation of the valve camshaft 12, and open and close the intake port and the exhaust port respectively.

[0103] As Figure 1 shown, for example, an oil outflow hole 21 is provided in the tappet 13. An oil drop hole 22 is provided from the valve cam chamber 11 to the crankcase 6. Thus, the insertion hole 16, the inside of the tappet 13, the oil outflow hole 21, the valve cam chamber 11, and the oil drop hole 22 constitute an oil return path 99. The oil return path 99 can return the oil in the valve cover 4 to the oil pan 7 via the inside of the crankcase 6. Each cylinder of the cylinder head 3 is connected to an intake passage 30 and an exhaust passage 31.

[0104] As Figure 1 shown, blow-by gas BG may be generated in at least any one of the compression stroke and the combustion stroke of the engine 1. The blow-by gas BG is gas that flows into the crankcase 6 through the gap between the piston 8 and the cylinder 5 as Figure 1 shown, and includes unburned fuel components, burned gas components, oil mists, etc. The blow-by gas BG leaking from the gap between the cylinder 5 and the piston 8 rises into the valve cover 4 through the oil return path 99, for example. That is, when the blow-by gas BG leaks from the gap between the cylinder 5 and the piston 8 to the crankcase 6, for example, it enters the valve cover 4 through the oil drop hole 22, the valve cam chamber 11, the oil outflow hole 21 of the tappet 13, and the insertion hole 16 of the oil return path 99 which serves as a blow-by gas passage path. It should be noted that the above oil return path 99 is an example of a blow-by gas passage path. The blow-by gas passage path is not limited to the above oil return path 99.

[0105] As Figure 1As shown, the blow-by gas treatment device 100 is provided in the cover 4. The blow-by gas treatment device 100 has the function of separating the blow-by gas BG into oil OL (refer to Figure 2 ) and the gas (treated gas) G after the fog with the oil OL separated (refer to Figure 2 ). For example, the gas G contained in the blow-by gas BG is transported through the blow-by gas treatment device 100 to the pipe 41 connected to the intake system outside the cover 4. The gas G contained in the blow-by gas BG is, for example, an unburned gas component or a combustion gas component after removing the oil OL and the fog of the oil OL from the blow-by gas BG. It should be noted that the oil (lubricant component) OL is recovered in the oil pan 7 through, for example, the cover 4, inside the cylinder head 3, and the oil return path 99.

[0106] Figure 1 The connecting pipe 50T of the intake pipe 50 shown is connected to the pipe 41 through the blow-by gas mixing joint 70. When new intake air AR is sucked into the intake pipe 50, it enters the main pipe 71 of the blow-by gas mixing joint 70 through the air cleaner 52 and the connecting pipe 50T. On the other hand, the gas G after the oil OL is separated from the blow-by gas BG by the blow-by gas treatment device 100 enters the sub-pipe 72 of the blow-by gas mixing joint 70 from the outlet part 40 of the blow-by gas treatment device 100 through the pipe 41. Thus, the new intake air AR and the gas G are mixed in the blow-by gas mixing joint 70 to become the intake air B.

[0107] On the other hand, the exhaust gas from the exhaust passage 31 is supplied to the turbine 62 of the turbocharger 60, thereby causing the turbine 62 and the blower 61 to rotate at high speed. The mixed intake air B is supplied to the blower 61 of the turbocharger 60 and is compressed. The compressed intake air C is supercharged to the intake passage 30 of the intake system.

[0108] (The blow-by gas treatment device 100 of the first embodiment)

[0109] Next, with reference to Figure 2 and Figure 3 a preferred structural example of the blow-by gas treatment device 100 of the first embodiment will be described.

[0110] Figure 2 is a cross-sectional view of the X-Z plane showing the structural example of the blow-by gas treatment device of the present embodiment.

[0111] Figure 3 is a perspective view with a cross-section of the X-Z plane showing the structural example of the blow-by gas treatment device of the present embodiment.

[0112] It should be noted that Figure 3(A) is a perspective view of a cross-section having an X-Z plane showing a structural example of the blow-by gas treatment device 100. Figure 3 (B) is an enlarged Figure 3 perspective view of a part of the blow-by gas treatment device 100 shown in (A).

[0113] Here, Figures 1 to 3 the X direction shown is Figure 1 the front-rear direction of the engine 1 shown, i.e., the axial direction of the crankshaft 9. The Y direction is the left-right direction of the engine 1. The Z direction is the up-down direction of the engine 1. The X, Y, and Z directions are mutually orthogonal.

[0114] As Figure 1 and Figure 2 shown, the blow-by gas treatment device 100 is also called a breather device or a breather device, and is disposed in the cover 4. As Figure 2 shown, the blow-by gas treatment device 100 can separate the blow-by gas BG into oil OL and gas G, and guide the oil OL and the gas G in their respective paths.

[0115] Figure 2 The blow-by gas treatment device 100 shown has a main structural part 101 and an outlet part 40. The main structural part 101 is disposed in the cover 4. The outlet part 40 is provided so as to protrude above the cover 4. Moreover, as Figure 2 shown, the outlet part 40 is disposed, for example, at a position CP substantially in the center in the X direction, i.e., the front-rear direction, of the main structural part 101. The outlet part 40 adjusts the pressure of the gas G at a position CP substantially in the center of the engine 1, and conveys only the gas G introduced from the main structural part 101 to the pipe 41 of the intake system of the engine 1. A pressure regulating valve (diaphragm) is provided in the outlet part 40. The pressure regulating valve provided in the outlet part 40 suppresses the new intake air AR from flowing into the engine 1 through the blow-by gas mixing joint 70 and the pipe 41 of the intake system.

[0116] <Main Structural Part 101 of Blow-by Gas Treatment Device 100>

[0117] First, with reference to Figures 1 to 3 a preferred structural example of the main structural part 101 of the blow-by gas treatment device 100 will be described.

[0118] As Figure 1 and Figure 2As shown, the main structural part 101 is accommodated in the cover 4. Specifically, the cover 4 has an upper part 4A, a front part 4B, a rear part 4C, and left and right side parts 4D. The main structural part 101 is arranged in the space surrounded by the upper part 4A, the front part 4B, the rear part 4C, and the left and right side parts 4D. The main structural part 101 takes in and guides the leaking gas BG, and separates the oil OL contained in the leaking gas BG from the leaking gas BG. Then, the main structural part 101 guides the oil OL and the gas G in their respective paths in such a way that the oil OL and the gas G separated from the leaking gas BG do not leak to the outside of the engine 1. Therefore, the cover 4 is held on the cylinder head 3 in a state where the inside of the cover 4 is airtight with respect to the outside of the cover 4. Thereby, leakage of the leaking gas BG, and the oil OL and the gas G separated from the leaking gas BG to the outside of the engine 1 is suppressed.

[0119] As Figure 2 shown, generally speaking, the main structural part 101 has a first leaking gas intake part 111, a second leaking gas intake part 112, a separation part 330, a first oil guiding groove part 151, a second oil guiding groove part 152, a first oil drain port 161, and a second oil drain port 162.

[0120] As Figure 2 shown, in order to form the above-described components, the main structural part 101 has a partition wall part 200, a guiding wall part 203, and a guiding plate 295. The partition wall part 200 is arranged horizontally in the X-Y plane within the cover 4, and partitions the lower region 4P of the cover 4 from the upper regions 4Q and 4R. Therefore, the lower region 4P and the upper regions 4Q and 4R become independent spaces from each other.

[0121] As Figure 2 shown, the guiding wall part 203 guides only the processed gas G, that is, the gas G after the oil OL has been separated from the leaking gas BG, to the outlet part 40. The guiding wall part 203 is arranged between the partition wall part 200 and the upper part 4A of the cover 4, and partitions the upper region 4Q from the upper region 4R. Therefore, the upper region 4Q and the upper region 4R become independent spaces from each other.

[0122] <First leaking gas intake part 111 and second leaking gas intake part 112>

[0123] Next, with reference to Figure 2 and Figure 3 the first leaking gas intake part 111 and the second leaking gas intake part 112 will be described.

[0124] The first blow-by gas intake part 111 and the second blow-by gas intake part 112 are holes formed by the partition wall part 200 and the guide plate 295 for taking in the blow-by gas BG. The partition wall part 200 is centered on the separation part 330 and is divided into the first guide lower surface part 231 side and the second guide lower surface part 232 side. The first blow-by gas intake part 111 is arranged at a position near the front part 4B (i.e., the front side of the engine 1) and takes in the blow-by gas BG from the front side. In addition, the second blow-by gas intake part 112 is arranged at a position near the rear part 4C (i.e., the rear side of the engine 1) and takes in the blow-by gas BG from the rear side. Figure 2 The shown guide plate 295 has a part that is away from the partition wall part 200 in a manner facing the first guide lower surface part 231 and the second guide lower surface part 232, and is arranged along the X-Y plane.

[0125] As Figure 1 shown, when the blow-by gas BG rising in the crankcase 6 reaches Figure 2 the lower region 4P of the shown cover 4, it is taken into the space between the first guide lower surface part 231 of the partition wall part 200 and the guide plate 295 through the first blow-by gas intake part 111 and is guided towards the separation part 330. Or, the blow-by gas BG is taken into the space between the second guide lower surface part 232 and the guide plate 295 through the second blow-by gas intake part 112 and is guided towards the separation part 330. Then, as Figure 2 and Figure 3 shown by the arrows, the blow-by gas BG reaches the impact member 120 of the separation part 330 at the central position RP in the front-rear direction, i.e., the X direction.

[0126] <Impact member 120 of the separation part 330>

[0127] Figure 2 The shown separation part 330 has an impact member 120, a filter 130, and a collision plate 133, and is arranged between the first blow-by gas intake part 111 and the second blow-by gas intake part 112 in the front-rear direction of the engine 1. More specifically, the separation part 330 is arranged at the central part, i.e., the central position RP, between the first oil drain port 161 and the second oil drain port 162 in the front-rear direction of the engine 1.

[0128] The impact member 120 functions as a nozzle or an orifice. The orifice 121 of the impact member 120 is a so-called longitudinal orifice whose axis is along the Z direction, i.e., the vertical direction or the up-and-down direction. The impact member 120 is an upward operation part that can increase the flow velocity of the leakage gas BG by allowing the leakage gas BG to pass upward along the orifice 121. The impact member 120 is disposed at the central position RP in the X direction of the partition wall portion 200. Thus, the leakage gas BG taken in by the first leakage gas intake portion 111 and the leakage gas BG taken in by the second leakage gas intake portion 112 are both more reliably guided to the impact member 120. On the basis of increasing the flow velocity of the leakage gas BG flowing into the orifice 121, the impact member 120 guides the leakage gas BG to the filter 130.

[0129] <Filter 130 of the separation portion 330>

[0130] As Figure 2 and Figure 3 shown in (B), the filter 130 is detachably mounted on the partition wall portion 200. The filter 130 is disposed between the collision plate 133 and the impact member 120. That is, the impact member 120 serving as a flow velocity increasing operation part is disposed on the lower surface of the filter 130. The collision plate 133 is disposed on the upper surface of the filter 130. The collision plate 133 is, for example, a metal plate and extends in the horizontal direction. The collision plate 133 collides with the leakage gas BG whose flow velocity has been increased and has passed through the filter 130, thereby separating it into oil OL and gas G that does not contain oil OL. The filter 130 is made of a material such as glass wool, for example. However, the material of the filter 130 is not particularly limited. The leakage gas BG with an increased flow velocity passes through the filter 130 while removing foreign matters and collides with the collision plate 133, thereby separating it into oil OL and gas G that does not contain oil OL. Then, the gas G separated from the leakage gas BG by the separation portion 330 is released from the filter 130.

[0131] As described above, the guide wall portion 203 is provided between the partition wall portion 200 and the upper surface portion 4A of the cover 4. Therefore, the gas G that does not contain oil OL and is released from the filter 130 is guided by the guide wall portion 203, passes through the passage 135 in the upper region 4Q, and is then led to the outlet portion 40.

[0132] The separation portion 330 is located at Figure 2 the central position RP in the X direction shown, and functions as a converging portion that can cause the leakage gas BG to converge from the front side and the rear side of the engine 1 toward the central portion in the X direction. In this way, since the separation portion 330 is located at the central position RP in the X direction of the cover 4, in the cover 4, the leakage gas BG is gathered from the front side and the rear side in the X direction at the central portion, and can be separated into oil OL and gas G that does not contain oil OL.

[0133] <First oil guiding groove portion 151 and second oil guiding groove portion 152>

[0134] Figure 2 The first oil guiding groove portion 151 shown is in a groove shape and is provided from the front portion 4B of the cover 4 to the vicinity of the filter 130. Similarly, the second oil guiding groove portion 152 is in a groove shape and is provided from the rear portion 4C of the cover 4 to the vicinity of the filter 130. The first oil guiding groove portion 151 and the second oil guiding groove portion 152 guide the oil OL separated from the leakage gas BG by the separating portion 330. The first oil guiding groove portion 151 is a specific structural example of the "first oil guiding portion" of the present invention, and can guide the oil OL released from the filter 130 Figure 1 when the engine 1 tilts forward to the front indicated by the X1 direction, and introduce it into the first oil drain port 161 on the front side. Similarly, the second oil guiding groove portion 152 is a specific structural example of the "second oil guiding portion" of the present invention, and can guide the oil OL released from the filter 130 Figure 1 when the engine 1 tilts backward to the rear indicated by the X2 direction, and introduce it into the second oil drain port 162 on the rear side.

[0135] It should be noted that the first oil guiding groove portion 151 and the second oil guiding groove portion 152 may also be connected to each other. In this case, the portion of one oil guiding groove portion provided from the filter 130 toward the front side of the engine 1 is referred to as the first oil guiding groove portion 151, and the portion provided from the filter 130 toward the rear side of the engine 1 is referred to as the second oil guiding groove portion 152.

[0136] <First oil drain port 161 and second oil drain port 162>

[0137] The first oil drain port 161 is provided on the front side of the engine 1 and is, for example, cylindrical. The first oil drain port 161 is provided downward in the Z1 direction within the cover 4 at a position in front of the first guiding lower surface portion 231 of the partition wall portion 200. The first oil drain port 161 has a check valve, temporarily stores the oil OL guided by the first oil guiding groove portion 151, and discharges it into the engine 1. Similarly, the second oil drain port 162 is provided on the rear side of the engine 1 and is, for example, cylindrical. The second oil drain port 162 is provided downward in the Z1 direction within the cover 4 at a position behind the second guiding lower surface portion 232 of the partition wall portion 200. The second oil drain port 162 has a check valve, temporarily stores the oil OL guided by the second oil guiding groove portion 152, and discharges it into the engine 1.

[0138] Accordingly, when the engine 1 tilts forward, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided by the first oil guiding groove portion 151 in the X1 direction. After being temporarily stored in the first oil drain port 161, it is discharged in the Z1 direction through the first oil drain port 161. Similarly, when the engine 1 tilts backward, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided by the second oil guiding groove portion 152 in the X2 direction. After being temporarily stored in the second oil drain port 162, it is discharged in the Z1 direction through the second oil drain port 162. In the cover 4, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is recovered in the oil pan 7 through the above-mentioned oil return path 99 as shown in Figure 1 the cover 4. Or, the discharged oil OL can be recovered in an oil container (not shown), for example. Thus, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is discharged into the engine 1 without leaking to the outside of the engine 1.

[0139] (Function example of the blow-by gas treatment device 100)

[0140] Next, with reference to Figures 1 to 3 a function example of the blow-by gas treatment device 100 in the above-mentioned engine 1 will be described.

[0141] From Figure 1 the blow-by gas BG leaking between the piston 8 and the cylinder 5 as shown reaches Figure 2 the lower region 4P of the cover 4 as shown. The blow-by gas BG is taken into the space between the first blow-by gas intake portion 111 and the guide plate 295 and between the second blow-by gas intake portion 112 and the guide plate 295, and is guided toward the separation unit 330. Then, the blow-by gas BG guided toward the separation unit 330 reaches the impact member 120 of the separation unit 330 located at the central position RP.

[0142] While increasing the flow rate of the blow-by gas BG flowing into the throttle hole 121, the impact member 120 guides the blow-by gas BG into the filter 130. The blow-by gas BG with increased flow rate collides with the collision plate 133 through the filter 130, and thus is separated into oil OL and gas G without oil OL in the form of mist.

[0143] The gas G separated from the blow-by gas BG by the separation unit 330 is released from the filter 130, rises and passes through the passage 135 in the upper region 4Q, and is delivered to the outlet portion 40.

[0144] On the other hand, when the engine 1 is tilted forward, the oil OL separated from the blow-by gas BG by the separation portion 330 is released from the filter 130, guided forward in the direction of X1 by the first oil guiding groove portion 151, and introduced into the first oil drain port 161 on the front side. Similarly, when the engine 1 is tilted backward, the oil OL separated from the blow-by gas BG by the separation portion 330 is released from the filter 130, guided backward in the direction of X2 by the second oil guiding groove portion 152, and introduced into the second oil drain port 162 on the rear side.

[0145] The oil OL guided by the first oil guiding groove portion 151 to the first oil drain port 161 is temporarily stored in the first oil drain port 161 and then discharged into the engine 1 through the check valve provided at the first oil drain port 161. Similarly, the oil OL guided by the second oil guiding groove portion 152 to the second oil drain port 162 is temporarily stored in the second oil drain port 162 and then discharged into the engine 1 through the check valve provided at the second oil drain port 162. The oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is recovered from the inside of the cover 4 through the oil return path 99 and in the oil pan 7, for example.

[0146] However, due to Figure 1 starting, stopping, accelerating, decelerating during the movement of the vehicle equipped with the engine 1 shown, or the uneven condition of the traveling surface such as the road surface, etc., the engine 1 tilts forward or backward. When the engine 1 tilts forward or backward, the liquid level of the oil accumulated in the oil pan 7 changes, and the air pressure of the gas present in the crankcase 6 sometimes changes. In addition, the air pressure of the gas present in the crankcase 6 changes according to the stroke of the engine 1. In this way, the oil OL separated from the blow-by gas BG is not sufficiently discharged, and sometimes is involved in the gas G separated from the blow-by gas BG and released to the outside of the engine 1 from the outlet portion of the blow-by gas treatment device.

[0147] In this regard, in the blow-by gas treatment device 100 according to the present embodiment and the engine 1 having the blow-by gas treatment device 100, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided by the first oil guiding groove portion 151 to the front side of the engine 1. After being temporarily stored in the first oil drain port 161, it is discharged into the engine 1. In addition, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided by the second oil guiding groove portion 152 to the rear side of the engine 1. After being temporarily stored in the second oil drain port 162, it is discharged into the engine 1. Therefore, in the blow-by gas treatment device 100 of the present embodiment, the discharge path of the oil OL separated from the blow-by gas BG by the separation unit 330 is clear. In addition, the gas G after the oil OL is separated from the blow-by gas BG is guided by the main structural portion 101 to the outlet portion 40 of the blow-by gas treatment device 100. Then, the outlet portion 40 of the blow-by gas treatment device 100 supplies the gas G introduced by the main structural portion 101 to the intake system of the engine 1. Thus, in the blow-by gas treatment device 100 of the present embodiment, the discharge path of the oil OL separated from the blow-by gas BG by the separation unit 330 and the discharge path of the gas G separated from the blow-by gas BG by the separation unit 330 are clearly distinguished. Thereby, even if the engine 1 tilts in the front-rear direction, it is possible to suppress the oil OL separated from the blow-by gas BG from being released from the outlet portion 40. In addition, since it is possible to suppress the inflow of the oil OL mist into the intake system, it is possible to suppress the combustion of the oil OL mist and to achieve the purification of the exhaust gas.

[0148] In addition, the separation unit 330 that separates the blow-by gas BG into the oil OL and the gas G is provided at the central position RP, that is, the central portion between the first oil drain port 161 that temporarily stores the oil OL guided by the first oil guiding groove portion 151 and discharges it into the engine 1 and the second oil drain port 162 that temporarily stores the oil OL guided by the second oil guiding groove portion 152 and discharges it into the engine 1. Thus, the separation unit 330 is provided at a position far from the first oil drain port 161 and the second oil drain port 162. Therefore, even if the engine 1 tilts in the front-rear direction, it is possible to suppress the oil OL temporarily stored in the first oil drain port 161 and the second oil drain port 162, the oil OL existing above the first oil drain port 161 and the second oil drain port 162, and the oil OL mist from being involved in the gas G separated from the blow-by gas BG by the separation unit 330 or being remixed. Thereby, even if the engine 1 tilts in the front-rear direction, it is possible to further suppress the oil OL separated from the blow-by gas BG from being released from the outlet portion 40.

[0149] In addition, since it is possible to suppress the oil OL and the mist of the oil OL from being involved in the gas G separated from the blow-by gas BG by the separation unit 330 or remixed, it is possible to suppress the release of the oil OL separated from the blow-by gas BG from the outlet unit 40 regardless of the position of the outlet unit 40. As a result, the degree of freedom in selecting the installation position and installation direction of the outlet unit 40 can be increased.

[0150] Since the first oil guide groove portion 151 and the second oil guide groove portion 152 are in a groove shape, a simple structure can be achieved, and even when the engine 1 is tilted in the front-rear direction, the oil OL separated from the blow-by gas BG by the separation unit 330 can be reliably guided to the front side and the rear side of the engine 1.

[0151] In addition, in the blow-by gas treatment device 100 according to the present embodiment, the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 for taking in the blow-by gas BG and the first oil guide groove portion 151 and the second oil guide groove portion 152 for guiding the oil OL are separately provided on both the upper surface side and the lower surface side via a common partition wall portion 200. Therefore, the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 and the first oil guide groove portion 151 and the second oil guide groove portion 152 can be provided on the partition wall portion 200 as one member. Therefore, the vertical dimension V of the blow-by gas treatment device 100 can be suppressed (refer to Figure 2 ). Therefore, the height dimension of the cover 4 in which the blow-by gas treatment device 100 is disposed can be suppressed, and the height dimension of the engine 1 having the blow-by gas treatment device 100 in the cover 4 can be suppressed.

[0152] In addition, after the flow rate of the blow-by gas BG is increased by the impact member 120, the blow-by gas BG collides with the collision plate 133 through the filter 130. Therefore, the blow-by gas BG is more reliably separated into the oil OL and the gas G from which the mist of the oil OL has been removed. In addition, the impact member 120 causes the flow rate of the blow-by gas BG to rise along the vertical direction (up and down direction) at the central position RP in the front-rear direction of the engine 1. In addition, the collision plate 133 extends along the horizontal direction and causes the blow-by gas BG that has passed through the filter 130 to collide. Therefore, compared with the case where the impact member causes the flow rate of the blow-by gas to rise along the horizontal direction and causes the blow-by gas to collide with the collision plate extending along the vertical direction, the vertical dimension V of the blow-by gas treatment device 100 can be suppressed.

[0153] Next, a second embodiment of the present invention will be described.

[0154] It should be noted that when the constituent elements of the blow-by gas treatment device in the second embodiment are the same as those of the blow-by gas treatment device in the first embodiment, the repeated description will be appropriately omitted, and hereinafter, the description will be centered on the differences.

[0155] (Leakage gas treatment device 100 of the second embodiment)

[0156] Refer to Figures 4 to 6 A preferred structural example of the leakage gas treatment device 100 of the second embodiment will be described.

[0157] Figure 4 It is a cross-sectional view of the X-Z plane showing a structural example of the leakage gas treatment device of this embodiment.

[0158] Figure 5 It is a perspective view showing a structural example of the outlet portion of the leakage gas treatment device of this embodiment.

[0159] Figure 6 Is Figure 5 A cross-sectional view of the cut surface A-A shown.

[0160] Here, as Figures 4 to 6 The X direction shown is Figure 1 The front-rear direction of the engine 1 shown, that is, the axial direction of the crankshaft 9. The Y direction is the left-right direction of the engine 1. The Z direction is the up-down direction of the engine 1. The X, Y, and Z directions are orthogonal to each other.

[0161] As Figure 1 And Figure 4 shown, the leakage gas treatment device 100 is also called a ventilation device or a venting device and is disposed in the cover 4. As Figure 4 shown, the leakage gas treatment device 100 can separate the leakage gas BG into oil OL and gas G, and can guide the oil OL and the gas G in their respective paths.

[0162] Figure 4 The leakage gas treatment device 100 shown has a main structural portion 101 and an outlet portion 40. The main structural portion 101 is disposed in the cover 4. The outlet portion 40 is protrudingly disposed above the cover 4. Moreover, as Figure 4 shown, the outlet portion 40 is disposed at a position CP that is approximately in the center in the X direction, that is, the front-rear direction, of the main structural portion 101. A detailed structural example of the outlet portion 40 will be described after a detailed structural example of the main structural portion 101 has been described.

[0163] <Main structural portion 101 of the leakage gas treatment device 100 of the second embodiment>

[0164] First, refer to Figure 1 And Figure 4 A preferred structural example of the main structural portion 101 of the leakage gas treatment device 100 of the second embodiment will be described.

[0165] As Figure 1and Figure 4 As shown in FIG. 4, the main structural part 101 is accommodated in the cover 4. Specifically, the cover 4 has an upper part 4A, a front part 4B, a rear part 4C, and left and right side parts 4D. The main structural part 101 is disposed in the space surrounded by the upper part 4A, the front part 4B, the rear part 4C, and the left and right side parts 4D. The main structural part 101 takes in and guides the leaking gas BG, and separates the oil OL contained in the leaking gas BG from the leaking gas BG. Then, the main structural part 101 guides the oil OL and the gas G in their respective paths in such a manner that the oil OL and the gas G separated from the leaking gas BG do not leak to the outside of the engine 1. Therefore, the cover 4 is held on the cylinder head 3 in a state where the inside of the cover 4 is airtight with respect to the outside of the cover 4. Thereby, leakage of the leaking gas BG, the oil OL separated from the leaking gas BG, and the gas G to the outside of the engine 1 is suppressed.

[0166] As Figure 4 shown in FIG. 5, generally speaking, the main structural part 101 has a first leaking gas intake part 111, a second leaking gas intake part 112, a separation part 330, a first oil guiding groove part 151, a second oil guiding groove part 152, a first oil drain port 161, and a second oil drain port 162. The first oil guiding groove part 151 and the second oil guiding groove part 152 are each an example of the "oil guiding part" of the present invention. The first oil drain port 161 and the second oil drain port 162 are each an example of the "oil drain port" of the present invention.

[0167] As Figure 4 shown in FIG. 6, in order to form the above-described components, the main structural part 101 has a partition wall part 200, a guiding wall part 203, and a guiding plate 295. The partition wall part 200 is horizontally disposed in the X-Y plane within the cover 4, and partitions the lower region 4P of the cover 4 from the upper regions 4Q and 4R. Therefore, the lower region 4P and the upper regions 4Q and 4R become independent spaces from each other.

[0168] As Figure 4 shown in FIG. 7, the guiding wall part 203 guides only the processed gas G, that is, the gas G after the oil OL has been separated from the leaking gas BG, to the outlet part 40. The guiding wall part 203 is disposed between the partition wall part 200 and the upper part 4A of the cover 4, and partitions the upper region 4Q from the upper region 4R. Therefore, the upper region 4Q and the upper region 4R become independent spaces from each other.

[0169] <First Leaking Gas Intake Part 111 and Second Leaking Gas Intake Part 112>

[0170] Next, the first leaking gas intake part 111 and the second leaking gas intake part 112 will be described with reference to FIG. 4.

[0171] The first blow-by gas intake part 111 and the second blow-by gas intake part 112 are holes formed by the partition wall part 200 and the guide plate 295 for taking in the blow-by gas BG. The partition wall part 200 is centered on the separation part 330 and is divided into the first guide lower surface part 231 side and the second guide lower surface part 232 side. The first blow-by gas intake part 111 is arranged at a position near the front part 4B (i.e., the front side of the engine 1) and takes in the blow-by gas BG from the front side. In addition, the second blow-by gas intake part 112 is arranged at a position near the rear part 4C (i.e., the rear side of the engine 1) and takes in the blow-by gas BG from the rear side. Figure 4 The shown guide plate 295 has a part that is away from the partition wall part 200 in a manner facing the first guide lower surface part 231 and the second guide lower surface part 232, and is arranged along the X-Y plane.

[0172] As Figure 1 shown, when the blow-by gas BG rising in the crankcase 6 reaches Figure 4 the lower area 4P of the shown cover 4, it is taken into the space between the first guide lower surface part 231 of the partition wall part 200 and the guide plate 295 through the first blow-by gas intake part 111 and is guided toward the separation part 330. Or, the blow-by gas BG is taken into the space between the second guide lower surface part 232 and the guide plate 295 through the second blow-by gas intake part 112 and is guided toward the separation part 330. Then, Figure 4 as shown by the arrow, the blow-by gas BG reaches the impact member 120 of the separation part 330 located at the central position RP in the front-rear direction, i.e., the X direction.

[0173] <Impact member 120 of the separation part 330>

[0174] Figure 4 The shown separation part 330 has an impact member 120, a filter 130, and a collision plate 133, and is arranged between the first blow-by gas intake part 111 and the second blow-by gas intake part 112 in the front-rear direction of the engine 1. More specifically, the separation part 330 is arranged at the central part, i.e., the central position RP, between the first oil drain port 161 and the second oil drain port 162 in the front-rear direction of the engine 1.

[0175] The impact member 120 functions as a nozzle or a throttle orifice. The axial direction of the throttle orifice 121 of the impact member 120 is a so-called longitudinal throttle orifice along the Z direction, i.e., the vertical direction or the up-and-down direction. The impact member 120 is a flow velocity increasing operation unit that can increase the flow velocity of the leakage gas BG by allowing the leakage gas BG to pass upward along the throttle orifice 121. The impact member 120 is disposed at the central position RP in the X direction of the partition wall portion 200. Thus, the leakage gas BG taken in by the first leakage gas intake portion 111 and the leakage gas BG taken in by the second leakage gas intake portion 112 are uniformly guided to the impact member 120. On the basis of increasing the flow velocity of the leakage gas BG flowing into the throttle orifice 121, the impact member 120 guides the leakage gas BG to the filter 130.

[0176] <Filter 130 of the separation portion 330>

[0177] As Figure 4 shown, the filter 130 is replaceably mounted on the partition wall portion 200. The filter 130 is disposed between the collision plate 133 and the impact member 120. That is, the impact member 120 serving as a flow velocity increasing operation unit is disposed on the lower surface of the filter 130. The collision plate 133 is disposed on the upper surface of the filter 130. The collision plate 133 is, for example, a metal plate and extends in the horizontal direction. The collision plate 133 collides with the leakage gas BG whose flow velocity has been increased and has passed through the filter 130, thereby separating it into the oil OL and the gas G of the mist containing no oil OL. The filter 130 is made of, for example, glass wool or the like. However, the material of the filter 130 is not particularly limited. The leakage gas BG with increased flow velocity passes through the filter 130 while removing foreign matters and collides with the collision plate 133, thereby separating it into the oil OL and the gas G of the mist containing no oil OL. Then, the gas G separated from the leakage gas BG by the separation portion 330 is released from the filter 130.

[0178] As described above, the guide wall portion 203 is provided between the partition wall portion 200 and the upper surface portion 4A of the cover 4. Therefore, the gas G of the mist containing no oil OL released from the filter 130 is guided by the guide wall portion 203, and after passing through the passage 135 in the upper region 4Q, it is led to the outlet portion 40. By disposing the guide wall portion 203 inside the cover 4, the gas G separated by the separation portion 330 can be guided to the outlet portion 40.

[0179] The separation portion 330 is located at Figure 4 the central position RP in the X direction shown, and functions as a collecting portion that can collect the leakage gas BG from the front side and the rear side of the engine 1 toward the central portion in the X direction. Thus, since the separation portion 330 is located at the central position RP in the X direction of the cover 4, the leakage gas BG is gathered at the central portion in the X direction from the front side and the rear side inside the cover 4, and can be separated into the oil OL and the gas G of the mist containing no oil OL.

[0180] <The first oil guiding groove portion 151 and the second oil guiding groove portion 152>

[0181] Figure 4 The shown first oil guiding groove portion 151 is in a groove shape and is provided near the filter 130 from the front portion 4B of the cover 4. Similarly, the second oil guiding groove portion 152 is in a groove shape and is provided near the filter 130 from the rear portion 4C of the cover 4. The first oil guiding groove portion 151 and the second oil guiding groove portion 152 guide the oil OL separated from the leakage gas BG by the separating portion 330. The first oil guiding groove portion 151 is a specific structural example of the "first oil guiding portion" of the present invention. When Figure 1 the engine 1 tilts forward, it can guide the oil OL released from the filter 130 forward in the direction shown by X1 and introduce it into the first oil drain port 161 on the front side. Similarly, the second oil guiding groove portion 152 is a specific structural example of the "second oil guiding portion" of the present invention. When Figure 1 the engine 1 tilts backward, it can guide the oil OL released from the filter 130 backward in the direction shown by X2 and introduce it into the second oil drain port 162 on the rear side.

[0182] It should be noted that the first oil guiding groove portion 151 and the second oil guiding groove portion 152 may also be connected to each other. In this case, the portion of one oil guiding groove portion that is provided from the filter 130 toward the front side of the engine 1 is referred to as the first oil guiding groove portion 151, and the portion that is provided from the filter 130 toward the rear side of the engine 1 is referred to as the second oil guiding groove portion 152.

[0183] <The first oil drain port 161 and the second oil drain port 162>

[0184] The first oil drain port 161 is provided on the front side of the engine 1 and is, for example, in a cylindrical shape. The first oil drain port 161 is provided downward in the Z1 direction within the cover 4 at a position in front of the first guiding lower surface portion 231 of the partition wall portion 200. The first oil drain port 161 has a check valve, temporarily stores the oil OL guided by the first oil guiding groove portion 151, and discharges it into the engine 1. Similarly, the second oil drain port 162 is provided on the rear side of the engine 1 and is, for example, in a cylindrical shape. The second oil drain port 162 is provided downward in the Z1 direction within the cover 4 at a position behind the second guiding lower surface portion 232 of the partition wall portion 200. The second oil drain port 162 has a check valve, temporarily stores the oil OL guided by the second oil guiding groove portion 152, and discharges it into the engine 1.

[0185] Accordingly, when the engine 1 is tilted forward, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided in the X1 direction by the first oil guiding groove unit 151, temporarily stored in the first oil drain port 161, and then discharged in the Z1 direction through the first oil drain port 161. Similarly, when the engine 1 is tilted backward, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided in the X2 direction by the second oil guiding groove unit 152, temporarily stored in the second oil drain port 162, and then discharged in the Z1 direction through the second oil drain port 162. In the cover 4, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is recovered in the oil pan 7 through the above-described oil return path 99 as shown in, for example, Figure 1 the cover 4. Alternatively, the discharged oil OL can be recovered in an oil container (not shown). Thus, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is discharged into the engine 1 without leaking to the outside of the engine 1.

[0186] <Structural Example of the Outlet Port 40 of the Blow-by Gas Treatment Device 100 of the Second Embodiment>

[0187] Next, a structural example of the outlet port 40 of the blow-by gas treatment device 100 of the second embodiment will be described with reference to Figures 4 to 6 the drawings.

[0188] As described above, Figure 4 the illustrated outlet port 40 is provided to protrude in the Z direction from the cover 4. The outlet port 40 is disposed, for example, at a substantially central position CP in the X direction (i.e., the front-rear direction) of the main structural portion 101 of the cover 4.

[0189] The outlet port 40 adjusts the pressure of the gas G at, for example, a substantially central position CP of the engine 1, and conveys only the gas G introduced from the main structural portion 101 to the pipe 41 of the intake system of the engine 1. A pressure regulating valve (diaphragm) 350 (see Figure 6 ) is provided in the outlet port 40. The pressure regulating valve 350 provided in the outlet port 40 suppresses the inflow of new intake air AR into the engine 1 through the blow-by gas mixing joint 70 and the pipe 41 of the intake system (see Figure 1 ).

[0190] As shown in Figure 5 and Figure 6 , the outlet port 40 can return the gas G separated from the blow-by gas BG by the separation unit 330 to the intake system of the engine 1 through the pipe 41 for re-combustion. Thus, it is possible to prevent the gas G separated from the blow-by gas BG from being released to the outside of the engine 1 and improve the environmental performance of the engine 1.

[0191] As shown in Figure 5 andFigure 6 As shown, the outlet portion 40 has an outlet mounting portion 700 and a container body 750 fixed to the outlet mounting portion 700. The outlet mounting portion 700 is a part of the cover 4 and is formed to bulge outward from the upper surface portion 4A of the cover 4 with the through-hole 680 for gas discharge provided in the cover 4 as the center. The through-hole 680 for gas discharge is provided to penetrate the upper surface portion 4A of the cover 4 in a circular shape along the Z direction. That is, the central axis of the through-hole 680 for gas discharge is along the Z direction. The through-hole 680 allows the gas G separated from the leaking gas BG by the separation portion 330 to pass through.

[0192] Figure 5 and Figure 6 The container body 750 shown is also referred to as a spacer or the like and is provided on the outlet mounting portion 700. The four corners of the container body 750 are detachably mounted on the outlet mounting portion 700 using, for example, four screws 751. Thus, the container body 750 can be removed from the outlet mounting portion 700, and an operator or the like can perform maintenance on the container body 750 and the outlet mounting portion 700 and replace the container body 750. The above-described pressure regulating valve 350 is mounted on the upper surface 702 of the container body 750.

[0193] As Figure 6 shown, the container body 750 is a substantially rectangular parallelepiped member having an inner space 720 on the lower side and an inner space 721 on the upper side. The inner spaces 720 and 721 are connected to each other and allow the gas G to pass through. The upper inner space 721 is connected to the pipe 41 as Figure 5 shown. The inner spaces 720 and 721 of the container body 750 temporarily accommodate the gas G rising from the inside of the cover 4 through the through-hole 680 of the outlet mounting portion 700 and can supply it to the intake system side of the engine 1 as Figure 1 shown.

[0194] As Figure 6 shown, the outlet mounting portion 700 has a mating surface 730 and an oil guiding inclined surface 740. The oil guiding inclined surface 740 of the present embodiment is an example of the "oil guiding surface" of the present invention. The mating surface 730 and the oil guiding inclined surface 740 are provided around the through-hole 680 with the through-hole 680 as the center. The mating surface 730 on the upper end side of the outlet mounting portion 700 is the portion that contacts and abuts against the mating surface 770 on the lower end side of the container body 750. The mating surfaces 730 and 770 are flat surfaces, parallel to the horizontal installation surface on which the vehicle carrying the engine is placed, and along the X-Y plane. That is, the mating surfaces 730 and 770 are horizontal. A sealing member 745 is provided between the mating surfaces 730 and 770. The sealing member 745 inhibits the gas G from leaking to the outside of the engine 1 through the gap between the mating surface 730 of the outlet mounting portion 700 and the mating surface 770 of the container body 750.

[0195] As Figure 6 shown, the oil guiding inclined surface 740 is a part connecting the mating surface 730 and the through hole 680, and is inclined downward from the mating surface 730 toward the through hole 680. The oil guiding inclined surface 740 guides the oil OL remaining in the gas G separated from the blow-by gas BG by the separating portion 330 into the cover 4. This will be described in detail later. As Figure 5 shown, the oil guiding inclined surface 740 is a part of the surface of a cone, specifically, a part of the surface of a conical body. That is, the oil guiding inclined surface 740 is the inner surface of the outlet mounting portion 700, and is a bowl-shaped inclined surface that tapers toward the front end as it goes from inside the container body 750 toward inside the cover 4. It should be noted that the oil guiding inclined surface 740 is not limited to being a part of the surface of a conical body. For example, it may be a part of the surface of a triangular pyramid or a part of the surface of a quadrangular pyramid. The oil guiding inclined surface 740 is formed by inclining at a specified inclination angle W with respect to the horizontal installation surface on which the vehicle equipped with the engine is located. The inclination angle W of the oil guiding inclined surface 740 is, for example, about 15 degrees or more and 30 degrees or less. Thereby, the dimension in the up-down direction (Z direction) of the engine 1 can be suppressed, and the oil OL remaining in the gas G separated from the blow-by gas BG by the separating portion 330 can be more reliably guided into the cover 4.

[0196] As Figure 6 shown, the upper end portion 741 of the oil guiding inclined surface 740 corresponds to the inner end portion of the mating surface 730 of the outlet mounting portion 700 and is almost covered by the mating surface 770 of the container body 750. That is, the upper end portion 741 of the oil guiding inclined surface 740 hardly protrudes into the internal space 720. Therefore, the horizontal mating surface 730 of the outlet mounting portion 700 hardly protrudes into the internal space 720. In addition, the lower end portion 742 of the oil guiding inclined surface 740 is gently and continuously formed on the inner peripheral surface 681 of the through hole 680. In this way, the oil guiding inclined surface 740 extends from the mating surface 770 of the container body 750 to the inner peripheral surface 681 of the through hole 680. In other words, the oil guiding inclined surface 740 is formed in the entire area from the mating surface 770 of the container body 750 to the inner peripheral surface 681 of the through hole 680.

[0197] (Function example of the blow-by gas treatment device 100 of the second embodiment)

[0198] Next, with reference to Figures 4 to 6 the function example of the blow-by gas treatment device 100 of the second embodiment will be described.

[0199] From Figure 1 the blow-by gas BG leaking between the piston 8 and the cylinder 5 shown reaches Figure 4The lower region 4P of the cover 4 shown. The leaking gas BG is taken in between the first leaking gas intake portion 111 and the second leaking gas intake portion 112 and between the first lower guiding surface portion 231 and the guiding plate 295 and between the second lower guiding surface portion 232 and the guiding plate 295, and is guided toward the separation portion 330. Then, the leaking gas BG guided toward the separation portion 330 reaches the impact member 120 of the separation portion 330 located at the central position RP.

[0200] On the basis of increasing the flow velocity of the leaking gas BG flowing into the throttle hole 121, the impact member 120 guides the leaking gas BG into the filter 130. The leaking gas BG with increased flow velocity collides with the collision plate 133 through the filter 130, and thus is separated into oil OL and gas G of a mist without oil OL.

[0201] The gas G separated from the leaking gas BG by the separation portion 330 is released from the filter 130, rises and is guided along the guiding wall portion 203, and thus is conveyed to the outlet portion 40 through the passage 135 in the upper region 4Q. The gas G conveyed to the outlet portion 40 passes through the through hole 680 of the outlet mounting portion 700 and is temporarily accommodated in the internal spaces 720, 721 of the container body 750. Then, when the internal pressure of the internal spaces 720, 721 is above a specified pressure, or when the internal pressure of the pipe 41 is below a specified pressure, the gas G temporarily accommodated in the internal spaces 720, 721 of the container body 750 passes through the pressure regulating valve 350 and is introduced into the sub-pipe 72 of the leaking gas mixing joint 70 through the pipe 41 and is mixed with the new intake air AR.

[0202] Here, there is a case where the separation portion 330 cannot completely separate the leaking gas BG into oil OL and gas G. For example, the oil OL contained in the leaking gas BG sometimes cannot be completely separated from the leaking gas BG by the separation portion 330 and is introduced into the outlet portion 40. In this way, the oil OL contained in the leaking gas BG may stay in the outlet portion 40. For example, if there is a horizontal plane in the path where the leaking gas BG flows in the outlet portion 40, the oil OL contained in the leaking gas BG may stay on the horizontal plane.

[0203] When the oil OL stays in the outlet portion 40, since the internal pressures of the internal spaces 720 and 721 of the outlet portion 40 are relatively high, even if the sealing member 745 is provided, the retained oil OL may leak out of the engine 1 through the gap between the mating surface 730 of the outlet mounting portion 700 and the mating surface 770 of the container body 750. Alternatively, when the oil OL stays in the outlet portion 40, the retained oil OL sometimes mixes with the water vapor contained in the blow-by gas BG to form an emulsion. When an emulsion is generated, the path of the blow-by gas BG may be blocked. When the path of the blow-by gas BG is blocked, the internal pressure of the engine 1 rises, and components such as the dipstick guide rod provided in the crankcase 6 may be damaged. In addition, when the path of the blow-by gas BG is blocked, the internal pressure of the engine 1 rises, and the turbocharger 60 may suck in the oil OL. Thus, when the oil OL contained in the blow-by gas BG stays in the outlet portion 40, problems such as the oil OL leaking out of the engine 1 and the path of the blow-by gas BG being blocked may occur.

[0204] In response to this, the outlet mounting portion 700 of the blow-by gas treatment device 100 of the present embodiment has an oil guiding inclined surface 740. As described above, the oil guiding inclined surface 740 inclines downward from the mating surface 730 toward the through hole 680. Therefore, even when the oil OL contained in the blow-by gas BG is introduced into the outlet portion 40, that is, even when the oil OL remains in the gas G separated from the blow-by gas BG by the separation portion 330, the oil OL flows through the oil guiding inclined surface 740 and is guided into the cover 4. Thereby, it is possible to suppress the oil OL contained in the blow-by gas BG from staying in the outlet portion 40.

[0205] The oil OL guided from the outlet portion 40 into the cover 4 by the oil guiding inclined surface 740 flows through the guiding wall portion 203 and is introduced into at least one of the first oil guiding groove portion 151 and the second oil guiding groove portion 152. At this time, when the guiding wall portion 203 inclines downward toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152, the oil OL is more smoothly introduced into at least one of the first oil guiding groove portion 151 and the second oil guiding groove portion 152 from the guiding wall portion 203. The oil OL introduced into the first oil guiding groove portion 151 is guided forward in the X1 direction shown by Figure 4 and is introduced into the front first oil drain port 161. In addition, the oil OL introduced into the second oil guiding groove portion 152 is guided backward in the X2 direction shown by Figure 4 and is introduced into the rear second oil drain port 162.

[0206] On the other hand, when the engine 1 is tilted forward, the oil OL separated from the blow-by gas BG by the separation portion 330 is released from the filter 130, guided forward in the direction shown by X1 by the first oil guiding groove portion 151, and introduced into the first oil drain port 161 on the front side. Similarly, when the engine 1 is tilted backward, the oil OL separated from the blow-by gas BG by the separation portion 330 is released from the filter 130, guided backward in the direction shown by X2 by the second oil guiding groove portion 152, and introduced into the second oil drain port 162 on the rear side.

[0207] The oil OL guided by the first oil guiding groove portion 151 to the first oil drain port 161 is temporarily stored in the first oil drain port 161 and then discharged into the engine 1 through the check valve provided at the first oil drain port 161. Similarly, the oil OL guided by the second oil guiding groove portion 152 to the second oil drain port 162 is temporarily stored in the second oil drain port 162 and then discharged into the engine 1 through the check valve provided at the second oil drain port 162. The oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is recovered in the oil pan 7, for example, through the oil return path 99 from within the cover 4.

[0208] In the blow-by gas treatment device 100 and the engine 1 according to the present embodiment, the outlet portion 40 has an oil guiding inclined surface 740 serving as an oil guiding surface for guiding the oil OL remaining in the gas G separated from the blow-by gas BG into the cover 4. Thus, even when there is oil OL remaining in the gas G separated from the blow-by gas BG by the separation portion 330, the blow-by gas treatment device 100 of the present embodiment can suppress the oil OL contained in the blow-by gas BG from staying in the outlet portion 40.

[0209] In addition, the oil guiding inclined surface 740 is inclined downward from the mating surface 730 toward the through hole 680. Therefore, the oil OL remaining in the gas G separated from the blow-by gas BG by the separation portion 330 flows downward along the oil guiding inclined surface 740 toward the through hole 680, passes through the through hole 680, and is more reliably guided into the cover. Thus, the blow-by gas treatment device 100 of the present embodiment can more reliably suppress the oil OL contained in the blow-by gas BG from staying in the outlet portion 40.

[0210] In addition, an oil guiding inclined surface 740 is formed in the entire area from the mating surface 730 to the inner peripheral surface 681 of the through hole 680. Therefore, it is possible to prevent the oil OL remaining in the gas G separated from the leakage gas BG by the separating portion 330 from being caught or staying in at least a part of the outlet portion 40, and the oil OL can smoothly flow downward toward the through hole 680 along the oil guiding inclined surface 740. Then, the oil OL flowing along the oil guiding inclined surface 740 toward the through hole 680 passes through the through hole 680 and is more reliably guided into the cover 4. Thus, the leakage gas processing device 100 of the present embodiment can more reliably prevent the oil OL contained in the leakage gas BG from staying in the outlet portion 40.

[0211] In addition, since the oil guiding inclined surface 740 is a part of the surface of a cone (a conical shape in the present embodiment), the oil OL remaining in the gas G separated from the leakage gas BG by the separating portion 330 can smoothly flow downward toward the through hole 680 along the oil guiding inclined surface 740.

[0212] In addition, the oil OL guided from the outlet portion 40 into the cover 4 by the oil guiding inclined surface 740 flows through the guiding wall portion 203 and is introduced into at least one of the first oil guiding groove portion 151 and the second oil guiding groove portion 152. The first oil guiding groove portion 151 can guide the oil OL separated from the leakage gas BG by the separating portion 330 to the first oil drain port 161, and can also guide the oil OL guided from the outlet portion 40 into the cover 4 by the oil guiding inclined surface 740 to the first oil drain port 161. In addition, the second oil guiding groove portion 152 can guide the oil OL separated from the leakage gas BG by the separating portion 330 to the second oil drain port 162, and can also guide the oil OL guided from the outlet portion 40 into the cover 4 by the oil guiding inclined surface 740 to the second oil drain port 162. Thus, the oil OL separated from the leakage gas BG is recovered, for example, in the oil pan 7 or the oil container provided in the engine 1, and the release from the outlet portion 40 is suppressed.

[0213] Furthermore, in the blow-by gas treatment device 100 according to the present embodiment and the engine 1 having the blow-by gas treatment device 100, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided to the front side of the engine 1 by the first oil guiding groove portion 151, and after being temporarily stored in the first oil drain port 161, it is discharged into the engine 1. In addition, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided to the rear side of the engine 1 by the second oil guiding groove portion 152, and after being temporarily stored in the second oil drain port 162, it is discharged into the engine 1. Therefore, in the blow-by gas treatment device 100 of the present embodiment, the discharge path of the oil OL separated from the blow-by gas BG by the separation unit 330 is clear. In addition, the gas G after the oil OL is separated from the blow-by gas BG is introduced into the outlet portion 40 of the blow-by gas treatment device 100 through the main structural portion 101. Then, the outlet portion 40 of the blow-by gas treatment device 100 supplies the gas G introduced by the main structural portion 101 to the intake system of the engine 1. In this way, in the blow-by gas treatment device 100 of the present embodiment, the discharge path of the oil OL separated from the blow-by gas BG by the separation unit 330 and the discharge path of the gas G separated from the blow-by gas BG by the separation unit 330 are clearly distinguished. Thereby, even if the engine 1 tilts in the front-rear direction, it is possible to suppress the oil OL separated from the blow-by gas BG from being released from the outlet portion 40. In addition, since it is possible to suppress the inflow of the oil OL mist into the intake system, it is possible to suppress the combustion of the oil OL mist and to achieve the purification of the exhaust gas.

[0214] In addition, the separation unit 330 that separates the blow-by gas BG into the oil OL and the gas G is provided at the central position RP, that is, the central portion between the first oil drain port 161 that temporarily stores the oil OL guided by the first oil guiding groove portion 151 and discharges it into the engine 1 and the second oil drain port 162 that temporarily stores the oil OL guided by the second oil guiding groove portion 152 and discharges it into the engine 1. In this way, the separation unit 330 is provided at a position far from the first oil drain port 161 and the second oil drain port 162. Therefore, even if the engine 1 tilts in the front-rear direction, it is possible to suppress the oil OL temporarily stored in the first oil drain port 161 and the second oil drain port 162, the oil OL existing above the first oil drain port 161 and the second oil drain port 162, and the oil OL mist from being involved in the gas G separated from the blow-by gas BG by the separation unit 330 or being remixed. Thereby, even if the engine 1 tilts in the front-rear direction, it is possible to further suppress the oil OL separated from the blow-by gas BG from being released from the outlet portion 40.

[0215] In addition, since it is possible to suppress the oil OL and the mist of the oil OL from being involved in the gas G separated from the blow-by gas BG by the separation unit 330 or remixed, it is possible to suppress the release of the oil OL separated from the blow-by gas BG from the outlet unit 40 regardless of the position of the outlet unit 40. As a result, the degree of freedom in selecting the installation position and installation direction of the outlet unit 40 can be increased.

[0216] Since the first oil guiding groove portion 151 and the second oil guiding groove portion 152 are in a groove shape, a simple structure can be achieved, and even when the engine 1 is tilted in the front-rear direction, the oil OL separated from the blow-by gas BG by the separation unit 330 can be reliably guided to the front side and the rear side of the engine 1.

[0217] In addition, in the blow-by gas treatment device 100 according to the present embodiment, the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 for taking in the blow-by gas BG and the first oil guiding groove portion 151 and the second oil guiding groove portion 152 for guiding the oil OL are separately provided on both the upper surface side and the lower surface side via a common partition wall portion 200. Therefore, the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 and the first oil guiding groove portion 151 and the second oil guiding groove portion 152 can be provided on the partition wall portion 200 as a single member. Therefore, the vertical dimension V of the blow-by gas treatment device 100 can be suppressed (refer to Figure 4 ). As a result, the height dimension of the cover 4 in which the blow-by gas treatment device 100 is disposed can be suppressed, and the height dimension of the engine 1 having the blow-by gas treatment device 100 in the cover 4 can be suppressed.

[0218] In addition, after the flow rate of the blow-by gas BG is increased by the impact member 120, the blow-by gas BG collides with the collision plate 133 through the filter 130. Therefore, the blow-by gas BG is more reliably separated into the oil OL and the gas G from which the mist of the oil OL has been removed. In addition, the impact member 120 causes the flow rate of the blow-by gas BG to rise along the vertical direction (up and down direction) at the central position RP in the front-rear direction of the engine 1. In addition, the collision plate 133 extends in the horizontal direction and causes the blow-by gas BG that has passed through the filter 130 to collide. Therefore, compared with the case where the impact member causes the flow rate of the blow-by gas to rise along the horizontal direction and the blow-by gas collides with the collision plate extending in the vertical direction, the vertical dimension V of the blow-by gas treatment device 100 can be suppressed.

[0219] Next, a third embodiment of the present invention will be described.

[0220] Note that, when components of the blowby gas treatment device of the third embodiment are the same as those of the first and second embodiments, duplicate descriptions are omitted and the following description will focus on differences.

[0221] (Blow-by Gas Treatment Device 100 of Third Embodiment)

[0222] Reference Figures 7 to 9 A preferred configuration example of the blowby gas treatment device 100 according to the third embodiment will be described.

[0223] Figure 7 It is a cross-sectional view taken along the XZ plane showing a configuration example of the blowby gas treatment device according to the present embodiment.

[0224] Figure 8 It is a perspective view showing a configuration example of a separation portion and its surrounding area of ​​the blowby gas treatment device according to the present embodiment.

[0225] Figure 9 yes Figure 8 1 is a cross-sectional view of a separation portion and its surrounding area taken along line DD in the Y direction of the blowby gas treatment device of the present embodiment shown.

[0226] Here, if Figures 7 to 9 The X direction shown is Figure 1 The front-rear direction of the engine 1 shown is the axial direction of the crankshaft 9. The Y direction is the left-right direction of the engine 1. The Z direction is the up-down direction of the engine 1. The X, Y, and Z directions are orthogonal to each other.

[0227] like Figure 1 and Figure 7 As shown, the blowby gas treatment device 100 can also be called a venting device or a gas release device, and is disposed in the cover 4. Figure 7 As shown, the blow-by gas processing device 100 can separate the blow-by gas BG into oil OL and gas G, and can guide the oil OL and the gas G in separate paths.

[0228] Figure 7 The blowby gas treatment device 100 shown in the figure has a main structure 101 and an outlet 40. The main structure 101 is arranged in the cover 4. The outlet 40 is arranged protrudingly above the cover 4. Figure 7As shown, the outlet portion 40 is disposed at a position CP that is approximately in the center in the X direction (front-rear direction) of the main structural portion 101. The outlet portion 40 adjusts the pressure of the gas G to be supplied to the intake system of the engine 1 at a position CP that is approximately in the center of the engine 1, and conveys only the gas G introduced from the main structural portion 101 to the pipe 41 of the intake system of the engine 1. A pressure regulating valve (diaphragm) is provided, for example, in the outlet portion 40. The pressure regulating valve provided in the outlet portion 40 suppresses the new intake air AR from flowing into the engine 1 via Figure 1 the shown blow-by gas mixing joint 70 and the pipe 41 of the intake system.

[0229] <The main structural portion 101 of the blow-by gas treatment device 100 according to the third embodiment>

[0230] First, with reference to Figure 1 and Figure 7 a preferred structural example of the main structural portion 101 of the blow-by gas treatment device 100 according to the third embodiment will be described.

[0231] As Figure 1 and Figure 7 shown, the main structural portion 101 is accommodated in the cover 4. Specifically, the cover 4 has an upper surface portion 4A, a front surface portion 4B, a rear surface portion 4C, and left and right surface portions 4D. The main structural portion 101 is disposed in the space surrounded by the upper surface portion 4A, the front surface portion 4B, the rear surface portion 4C, and the left and right surface portions 4D. As Figure 7 shown, the main structural portion 101 takes in and guides the blow-by gas BG, and separates the oil OL and the gas G contained in the blow-by gas BG from the blow-by gas BG. Then, the main structural portion 101 guides the oil OL and the gas G in their respective paths so that the oil OL and the gas G separated from the blow-by gas BG do not leak to the outside of the engine 1. Therefore, the cover 4 is held on the cylinder head 3 in a state where the inside of the cover 4 is airtight with respect to the outside of the cover 4. Thereby, leakage of the blow-by gas BG and the oil OL and the gas G separated from the blow-by gas BG to the outside of the engine 1 is suppressed.

[0232] As Figure 7 shown, generally speaking, the main structural portion 101 has a first blow-by gas intake portion 111, a second blow-by gas intake portion 112, a separation portion 330, a first oil guiding groove portion 151, a second oil guiding groove portion 152, a first oil drain port 161, and a second oil drain port 162. The first oil guiding groove portion 151 and the second oil guiding groove portion 152 are each an example of the "oil guiding portion" of the present invention.

[0233] As Figure 7As shown, in order to form the above-described constituent elements, the main structural portion 101 includes a partition wall portion 200, a guide wall portion 203, and a guide plate 295. The partition wall portion 200 is horizontally disposed in the X-Y plane within the cover 4, partitioning the lower region 4P of the cover 4 from the upper regions 4Q and 4R. Accordingly, the lower region 4P and the upper regions 4Q and 4R become independent spaces from each other.

[0234] As Figure 7 shown, the guide wall portion 203 reliably guides only the processed gas G, i.e., the gas G after the oil OL has been separated from the leakage gas BG, to the outlet portion 40. The guide wall portion 203 is disposed between the partition wall portion 200 and the upper surface portion 4A of the cover 4, partitioning the upper region 4Q from the upper region 4R. Accordingly, the upper region 4Q and the upper region 4R become independent spaces from each other.

[0235] <First leakage gas intake portion 111 and second leakage gas intake portion 112>

[0236] Next, the first leakage gas intake portion 111 and the second leakage gas intake portion 112 will be described with reference to Figure 7 them.

[0237] The first leakage gas intake portion 111 and the second leakage gas intake portion 112 are holes formed by the partition wall portion 200 and the guide plate 295 for taking in the leakage gas BG. The partition wall portion 200 is divided into a first guide lower surface portion 231 side and a second guide lower surface portion 232 side with the separation portion 330 as the center. The first leakage gas intake portion 111 is provided at a position near the front surface portion 4B (i.e., the front side of the engine 1) and takes in the leakage gas BG from the front side. In addition, the second leakage gas intake portion 112 is provided at a position near the rear surface portion 4C (i.e., the rear side of the engine 1) and takes in the leakage gas BG from the rear side. Figure 7 The shown guide plate 295 has a portion that is away from the partition wall portion 200 so as to face the first guide lower surface portion 231 and the second guide lower surface portion 232, and is disposed along the X-Y plane.

[0238] As Figure 1 shown, when the leakage gas BG that has risen within the crankcase 6 reaches Figure 7 the lower region 4P of the shown cover 4, it is taken into the space between the first guide lower surface portion 231 of the partition wall portion 200 and the guide plate 295 via the first leakage gas intake portion 111 and is guided toward the separation portion 330. Alternatively, the leakage gas BG is taken into the space between the second guide lower surface portion 232 and the guide plate 295 via the second leakage gas intake portion 112 and is guided toward the separation portion 330. Then, as shown by the arrow in Figure 7 them, the leakage gas BG reaches the impact member 120 of the separation portion 330 located at the central position RP in the front-rear direction, i.e., the X direction.

[0239] <Separator section 330>

[0240] Next, with reference to Figures 7 to 9 a preferred structural example of the separator section 330 will be described.

[0241] Figure 7 The separator section 330 shown is also called an impactor type separator and has an impactor 120, a filter 130

[0242] and a collision plate 133, and is disposed between the first blow-by gas intake section 111 and the second blow-by gas intake section 112 in the front-rear direction of the engine 1. More specifically, the separator section 330 is disposed at the central position RP, which is the central portion between the first oil drain port 161 and the second oil drain port 162 in the front-rear direction of the engine 1.

[0243] As Figure 8 and Figure 9As shown, the separation section 330 is provided on the partition wall section 200 of the cover 4 at a prescribed inclination angle θ with respect to the horizontal plane along the X-Y plane. Specifically, the separation section 330 is provided so as to be inclined in a direction in which the oil OL separated from the leaking gas BG by the separation section 330 is introduced into the first oil guiding groove section 151 and the second oil guiding groove section 152. More specifically, the upper surface 122 of the impact member 120 is inclined at a prescribed inclination angle θ with respect to the horizontal plane along the X-Y plane. The upper surface 122 is the surface of the impact member 120 that faces the inner surface (i.e., the lower surface) of the collision plate 133, and is an example of the "surface" of the present invention. The upper surface 122 of the impact member 120 is inclined downward toward the first oil guiding groove section 151 and the second oil guiding groove section 152. The filter 130 and the collision plate 133 are placed on the setting sections 400, 400 provided on the upper surface 122 of the impact member 120, are inclined at a prescribed inclination angle θ with respect to the horizontal plane, and are detachably fixed. The separation section 330 is provided so as to be inclined and descend toward the first oil guiding groove section 151 and the second oil guiding groove section 152 side. The inclination angle θ is, for example, about 5 degrees or more and 45 degrees or less. When the inclination angle θ is less than 5 degrees, it is difficult to quickly guide the oil OL separated from the leaking gas BG by the separation section 330 to the first oil guiding groove section 151 and the second oil guiding groove section 152 via the oil outlet inclined guiding section 500. On the other hand, when the inclination angle θ is greater than 45 degrees, the separated oil OL can be quickly guided to the first oil guiding groove section 151 and the second oil guiding groove section 152 via the oil outlet inclined guiding section 500. However, on the other hand, the effective opening area of the inlet portion of the throttle hole 121 of the impact member 120 becomes narrow, and it is difficult to guide the leaking gas BG to the impact member 120. In particular, when the inclination angle θ is, for example, 60 degrees or more, the effective opening area of the inlet portion of the throttle hole 121 of the impact member 120 becomes particularly narrow. Then, the leaking gas BG stays in the inlet portion of the throttle hole 121 of the impact member 120, increasing the risk of moisture condensation in the leaking gas BG.

[0244] Next, with reference to Figures 7 to 9 each component of the separation section 330 will be described in order.

[0245] <Impact member 120 of separation section 330>

[0246] Figure 7 The shown impact member 120 has the function of a nozzle or a throttle hole. As Figure 9 shown, the impact member 120 preferably has at least two throttle holes 121. The throttle hole 121 is a hole penetrating the impact member 120. The direction of the axis 121C of the throttle hole 121 is not along the Z direction, that is, the vertical direction or the up-and-down direction, but is inclined with respect to the Z direction at the above-described inclination angle θ. That is, the axis 121C of the throttle hole 121 is orthogonal to the inner surface of the collision plate 133.

[0247] The two throttle holes 121, 121 are, for example, through holes with a circular cross-section, and in Figure 8 and Figure 9 the example shown, as Figure 9 (A) shows, they are arranged linearly along the Y direction. As another example, as Figure 9 (B) shows, the two throttle holes 121, 121 can also be arranged staggeredly in the Y direction. In other words, when viewed along the Y direction, the two throttle holes 121, 121 can also be arranged at positions offset from each other in the X direction. The arrangement of the two throttle holes 121, 121 will be described in detail later. It should be noted that the set number of the throttle holes 121 is not limited to two, and can also be one or three. In addition, the cross-sectional shape of the throttle hole 121 is not limited to a circular shape, and can also be triangular, quadrilateral, etc.

[0248] The impact member 120 is a flow velocity increasing operation part that allows the leakage gas BG to pass obliquely upward along the throttle hole 121, thereby enabling the flow velocity of the leakage gas BG to increase. The impact member 120 is arranged at the central position RP in the X direction of the partition wall part 200. Thus, the leakage gas BG taken in by the first leakage gas intake part 111 and the leakage gas BG taken in by the second leakage gas intake part 112 are evenly guided to the impact member 120. On the basis of increasing the flow velocity of the leakage gas BG flowing into the throttle hole 121, the impact member 120 guides the leakage gas BG to the filter 130.

[0249] <The filter 130 of the separation part 330>

[0250] As Figure 7 and Figure 8 shown, the filter 130 is detachably installed on the partition wall part 200, that is, on the setting parts 400, 400. The filter 130 is made of, for example, glass wool and the like. However, the material of the filter 130 is not particularly limited. The filter 130 is fixed by the mounting screws 139, 139 in such a way that it is clamped between the collision plate 133 and the setting parts 400, 400 of the impact member 120. That is, the impact member 120 as the flow velocity increasing operation part is arranged on the lower surface of the filter 130. The collision plate 133 is arranged on the upper surface of the filter 130. The collision plate 133 is, for example, a metal plate and extends in a parallel direction with respect to the upper surface 122 of the impact member 120. The collision plate 133 has, for example, threaded holes 138, 138 through which the two mounting screws 139, 139 pass.

[0251] As Figure 8 and Figure 9As shown, on the upper surface 122 of the impact member 120, there are provided convex-shaped setting portions 400, 400 that protrude outward from the upper surface 122 of the impact member 120. The setting portions 400, 400 are portions for tilting the filter 130 and the collision plate 133 downward toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152. Specifically, they are portions for detachably fixing the filter 130 and the collision plate 133 in a state tilted at the above-mentioned tilt angle θ. The setting portions 400, 400 are formed in a circularly bulging manner on the upper surface 122 of the impact member 120. The positions of the respective setting portions 400, 400 correspond to the positions of the threaded holes 138, 138 of the collision plate 133. The respective setting portions 400, 400 are provided to be tilted in a direction for guiding the oil OL separated from the bypass gas BG into the first oil guiding groove portion 151 and the second oil guiding groove portion 152 that are oil guiding portions.

[0252] As Figure 8 shown, an oil guiding gap region 401 is formed between the two setting portions 400, 400. The oil guiding gap region 401 is a space formed between the impact member 120 and the filter 130. That is, the setting portions 400, 400 form the oil guiding gap region 401 that is a space between the impact member 120 and the filter 130. As Figure 8 shown, two throttle holes 121, 121 are provided so as to penetrate through the portion of the impact member 120 in the oil guiding gap region 401. The two throttle holes 121, 121 of the impact member 120 cause the flow rate of the bypass gas BG to rise in an obliquely upward direction and supply it to the filter 130. Internal thread portions 402 are provided on the respective setting portions 400. Each mounting screw 139 passes through the threaded hole 138 of the collision plate 133 and the filter 130 and is fastened to the internal thread portion 402 of the setting portion 400. Thereby, the filter 130 is detachably fixed between the collision plate 133 and the setting portion 400.

[0253] As Figure 9 exemplified in , as the bypass gas BG flows into the throttle hole 121 of the impact member 120 and rises obliquely upward in the Y-Z plane in the direction of arrow G1, the flow rate is increased. The bypass gas BG with an increased flow rate removes foreign matters through the filter 130 and collides with the lower surface of the collision plate 133, thereby being separated into oil OL and gas G.

[0254] The gas G separated from the bypass gas BG by the separation portion 330 is released from the filter 130. As described above, the guide wall portion 203 is provided between the partition wall portion 200 and the upper surface portion 4A of the cover 4. Therefore, the gas G that does not contain the oil OL mist released from the filter 130 is guided by the guide wall portion 203, passes through the passage 135 in the upper region 4Q, and is introduced into the outlet portion 40.

[0255] On the other hand, the oil OL separated from the leakage gas BG by the separation unit 330 falls after passing through the filter 130 as shown by the arrow G2 in Figure 9 and lands on the upper surface 122 of the impact member 120 in the oil guiding gap region 401. The oil OL that lands on the upper surface 122 of the impact member 120 flows along the upper surface 122 of the impact member 120 in the oil guiding gap region 401 and flows toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152.

[0256] The separation unit 330 having the above structure is located at the central position RP in the X direction shown in Figure 7 and functions as a converging unit that can cause the leakage gas BG to converge from the front side and the rear side of the engine 1 toward the central portion in the X direction. Thus, since the separation unit 330 is located at the central position RP in the X direction of the cover 4, in the X direction within the cover 4, the leakage gas BG can be gathered from the front side and the rear side toward the central portion and separated into the oil OL and the gas G that does not contain the oil OL in the form of a mist.

[0257] <Oil outlet inclined guiding portion 500 and oil inclined guiding return portion 600>

[0258] Next, the oil outlet inclined guiding portion 500 and the oil inclined guiding return portion 600 will be described with reference to Figure 8 and Figure 9 as shown in.

[0259] As Figure 8 and Figure 9 shown, the oil outlet inclined guiding portion 500 is provided between the oil guiding gap region 401, the first oil guiding groove portion 151, and the second oil guiding groove portion 152. The oil outlet inclined guiding portion 500 is connected to the upper surface 122 of the impact member 120 in the oil guiding gap region 401, the first oil guiding groove portion 151, and the second oil guiding groove portion 152 and is formed to be inclined in a direction descending from the upper surface 122 of the impact member 120 toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152. That is, the oil outlet inclined guiding portion 500 is formed to be inclined in a direction descending from the upper surface 122 of the impact member 120 toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152 in order to introduce the oil OL separated from the leakage gas BG by the separation unit 330 and flowing along the upper surface 122 of the impact member 120 into the first oil guiding groove portion 151 and the second oil guiding groove portion 152 that serve as oil guiding portions.

[0260] The inclination angle θ1 of the oil outlet inclined guide portion 500 with respect to the horizontal plane (X-Y plane) is preferably greater than the inclination angle θ of the upper surface 122 of the impact member 120 with respect to the horizontal plane. When the inclination angle θ1 is greater than the inclination angle θ, the oil OL separated by the separation portion 330 from the bypass gas BG and flowing and falling along the upper surface 122 of the impact member 120 has a faster flow rate when it falls onto the oil outlet inclined guide portion 500 than when the oil OL flows through the upper surface 122 of the impact member 120. Therefore, the oil OL separated from the bypass gas BG by the separation portion 330 can be quickly introduced from the upper surface 122 of the impact member 120 into the first oil guide groove portion 151 and the second oil guide groove portion 152. In addition, since the oil OL is not likely to stay on the upper surface 122 of the impact member 120, it is possible to prevent the oil OL separated from the bypass gas BG by the separation portion 330 from being mixed into the bypass gas BG again.

[0261] In addition, as Figure 8 and Figure 9 shown, when viewed from the first oil guide groove portion 151 and the second oil guide groove portion 152, the oil inclined guide return portion 600 is provided on the side opposite to the oil outlet inclined guide portion 500. That is, the oil outlet inclined guide portion 500 is provided on one side of the first oil guide groove portion 151 and the second oil guide groove portion 152 (the side where the separation portion 330 is provided), and the oil inclined guide return portion 600 is provided on the other side of the first oil guide groove portion 151 and the second oil guide groove portion 152. The oil inclined guide return portion 600 is inclinedly formed from the lowermost position of the oil outlet inclined guide portion 500 in a manner having an inclination opposite to that of the oil outlet inclined guide portion 500. That is, as Figure 9 illustrated, the oil outlet inclined guide portion 500 and the oil inclined guide return portion 600 are formed in a substantially V shape when viewed in cross section. The inclination angle θ2 of the oil inclined guide return portion 600 is not particularly limited. For example, it is set to an angle approximately the same as the inclination angle θ1 or smaller than the inclination angle θ1. The inclination angle θ2 of the oil inclined guide return portion 600 is, for example, about 5 degrees or more and 10 degrees or less. When the inclination angle θ2 of the oil inclined guide return portion 600 is less than 5 degrees, it is difficult to quickly guide the oil OL temporarily stored or concentrated in the oil inclined guide return portion 600 to the first oil guide groove portion 151 and the second oil guide groove portion 152. In addition, when the inclination angle θ2 of the oil inclined guide return portion 600 is greater than 10 degrees, the speed of guiding the oil OL temporarily stored or concentrated in the oil inclined guide return portion 600 to the first oil guide groove portion 151 and the second oil guide groove portion 152 is too fast, and the oil OL may return to the oil outlet inclined guide portion 500 on the opposite side.

[0262] When the oil OL separated from the leakage gas BG by the separation unit 330 flows from the upper surface 122 of the impact member 120 through the oil outlet inclined guide portion 500, in order to prevent the oil OL from flowing out of the oil outlet inclined guide portion 500, the first oil guide groove portion 151, and the second oil guide groove portion 152 due to the flow trend of the oil OL during flow, the oil inclined guide return portion 600 temporarily stores or concentrates the oil OL. Then, the oil inclined guide return portion 600 guides and returns the oil OL to the first oil guide groove portion 151 and the second oil guide groove portion 152. In this way, the oil inclined guide return portion 600 has a temporary oil buffering function or a concentrating function for temporarily storing the oil OL separated from the leakage gas BG by the separation unit 330 and guiding and returning it to the first oil guide groove portion 151 and the second oil guide groove portion 152. As Figure 9 shown, the oil inclined guide return portion 600 has a step 601 in order to more reliably suppress the oil OL from flowing out of the oil outlet inclined guide portion 500, the first oil guide groove portion 151, and the second oil guide groove portion 152.

[0263] As Figure 8 and as Figure 9 shown, the lowermost part of the oil outlet inclined guide portion 500 and the lowermost part of the oil inclined guide return portion 600 are connected at the cross-connection position S. The cross-connection position S extends in the X direction and is located between the first oil guide groove portion 151 and the second oil guide groove portion 152.

[0264] In addition, as Figure 8 shown, the width W2 in the X direction of the oil inclined guide return portion 600 is set to be greater than the width W1 in the X direction of the oil outlet inclined guide portion 500. The width W1 in the X direction and the width W2 in the X direction are examples of the "length" in the "direction in which the oil guide portion extends" of the present invention. Thus, even when the oil OL separated from the leakage gas BG by the separation unit 330 flows from the upper surface 122 of the impact member 120 through the oil outlet inclined guide portion 500, the oil inclined guide return portion 600 can suppress the flowing oil OL from overflowing and can sufficiently accommodate the oil OL, and then make the oil OL flow and return to the first oil guide groove portion 151 and the second oil guide groove portion 152.

[0265] <The first oil guide groove portion 151 and the second oil guide groove portion 152>

[0266] Figure 7The first oil guiding groove portion 151 shown is in a groove shape, provided from the front portion 4B of the cover 4 to the vicinity of the filter 130, and inclined downward from the filter 130 toward the front portion 4B of the cover 4. Similarly, the second oil guiding groove portion 152 is in a groove shape, provided from the rear portion 4C of the cover 4 to the vicinity of the filter 130, and inclined downward from the filter 130 toward the rear portion 4C of the cover 4. The first oil guiding groove portion 151 and the second oil guiding groove portion 152 guide the oil OL separated from the blow-by gas BG by the separating portion 330. The first oil guiding groove portion 151 is a specific structural example of the "first oil guiding portion" of the present invention. When the engine 1 shown in Figure 1 tilts forward, it can guide the oil OL released from the filter 130 forward in the direction shown by X1 and introduce it into the first oil drain port 161 on the front side. Similarly, the second oil guiding groove portion 152 is a specific structural example of the "second oil guiding portion" of the present invention. When the engine 1 shown in Figure 1 tilts backward, it can guide the oil OL released from the filter 130 backward in the direction shown by X2 and introduce it into the second oil drain port 162 on the rear side.

[0267] The first oil guiding groove portion 151 and the second oil guiding groove portion 152 are connected to each other via the above-mentioned oil outlet inclined guiding portion 500 and the oil inclined guiding return portion 600.

[0268] <The first oil drain port 161 and the second oil drain port 162>

[0269] The first oil drain port 161 is provided on the front side of the engine 1 and is, for example, cylindrical. The first oil drain port 161 is provided in the cover 4 downward in the Z1 direction at a position in front of the first guiding lower surface portion 231 of the partition wall portion 200. The first oil drain port 161 has a check valve, temporarily stores the oil OL guided by the first oil guiding groove portion 151, and discharges it into the engine 1. Similarly, the second oil drain port 162 is provided on the rear side of the engine 1 and is, for example, cylindrical. The second oil drain port 162 is provided in the cover 4 downward in the Z1 direction at a position behind the second guiding lower surface portion 232 of the partition wall portion 200. The second oil drain port 162 has a check valve, temporarily stores the oil OL guided by the second oil guiding groove portion 152, and discharges it into the engine 1.

[0270] Accordingly, when the engine 1 tilts forward, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided by the first oil guiding groove unit 151 in the X1 direction. After being temporarily stored in the first oil drain port 161, it is discharged in the Z1 direction through the first oil drain port 161. Similarly, when the engine 1 tilts backward, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided by the second oil guiding groove unit 152 in the X2 direction. After being temporarily stored in the second oil drain port 162, it is discharged in the Z1 direction through the second oil drain port 162. Inside the cover 4, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162, for example, is recovered from the Figure 1 illustrated cover 4 through the above-mentioned oil return path 99 in the oil pan 7. Alternatively, the discharged oil OL can also be recovered in an oil container (not shown). Thus, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is discharged into the engine 1 without leaking to the outside of the engine 1.

[0271] (Function example of the blow-by gas treatment device 100 of the third embodiment)

[0272] Next, with reference to Figures 7 to 8 a function example of the blow-by gas treatment device 100 of the third embodiment will be described.

[0273] From Figure 1 the blow-by gas BG leaking between the piston 8 and the cylinder 5 shown reaches Figure 7 the lower region 4P of the cover 4 shown. The blow-by gas BG is taken into the space between the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112, between the first guiding lower surface portion 231 and the guiding plate 295, and between the second guiding lower surface portion 232 and the guiding plate 295, and is guided toward the separation unit 330. Then, the blow-by gas BG guided toward the separation unit 330 reaches the impact member 120 of the separation unit 330 located at the central position RP.

[0274] On the basis of increasing the flow rate of the blow-by gas BG flowing into the throttle hole 121, Figure 7 and Figure 9 the impact member 120 shown guides the blow-by gas BG along the direction of the axis 121C of the throttle hole 121 inclined at an inclination angle θ, that is, along Figure 9It is introduced into the filter 130 in the direction of the arrow G1 shown. The bypass gas BG with an increased flow rate collides with the inner surface (i.e., the lower surface) of the collision plate 133 through the filter 130. At this time, the axis 121C of the throttle hole 121 is orthogonal to the inner surface of the collision plate 133. Therefore, the bypass gas BG passing through the throttle hole 121 and with an increased flow rate collides perpendicularly with the inner surface of the collision plate 133. As a result, the bypass gas BG receives a stronger impact force from the collision plate 133 and is more reliably separated into oil OL and oil-free fog gas G.

[0275] As Figure 7 shown, the gas G separated from the bypass gas BG by the separation unit 330 is released from the filter 130, rises and passes through the passage 135 in the upper region 4Q, and is conveyed to the outlet unit 40.

[0276] On the other hand, the oil OL separated from the bypass gas BG by the separation unit 330 falls along Figure 9 the arrow G2 shown through the inside of the filter 130 and falls onto the upper surface 122 of the impact member 120 in the oil guiding gap region 401. In this way, the oil OL separated from the bypass gas BG by the collision plate 133 is in a direction different from the flow direction of the bypass gas BG colliding with the inner surface of the collision plate 133 ( Figure 9 the direction of the arrow G1 shown) ( Figure 9 the direction of the arrow G2 shown, i.e., the vertical direction) and falls onto the upper surface 122 of the impact member 120. Therefore, it is possible to prevent the oil OL separated from the bypass gas BG by the collision plate 133 from entering the throttle hole 121 and prevent the throttle hole 121 from being blocked.

[0277] Here, when the surface of the impact member opposite to the collision plate 133 that separates the bypass gas BG into oil OL and gas G is parallel to the horizontal plane, the oil OL separated from the bypass gas BG may stay on the surface of the impact member. The oil OL separated from the bypass gas BG contains moisture (water vapor). Therefore, when the temperature is relatively low, the moisture contained in the oil OL staying on the surface of the impact member sometimes condenses on the surface of the impact member. In this way, the through holes formed in the impact member and through which the bypass gas BG passes are blocked. When the through holes of the impact member are blocked, there will be a problem that the bypass gas BG cannot be separated into oil OL and gas G.

[0278] Therefore, in the leakage gas processing device 100 of the present embodiment, the separation unit 330 is provided at a predetermined inclination angle θ with respect to the horizontal plane along the X-Y plane in the partition wall portion 200 of the cover 4. Specifically, the separation unit 330 is provided to be inclined in a direction in which the oil OL separated from the leakage gas BG by the separation unit 330 is introduced into the first oil guiding groove portion 151 and the second oil guiding groove portion 152. More specifically, the upper surface 122 of the impact member 120 is inclined at a predetermined inclination angle θ with respect to the horizontal plane along the X-Y plane. Therefore, the oil OL falling on the upper surface 122 of the impact member 120 flows on the upper surface 122 of the impact member 120 inclined at the inclination angle θ due to its own weight, and flows into the oil outlet inclined guiding portion 500 having a larger inclination angle θ1.

[0279] Thus, the oil OL separated from the leakage gas BG is reliably introduced from the upper surface 122 of the impact member 120 into the oil outlet inclined guiding portion 500. Moreover, even if the oil OL strongly flows into the oil outlet inclined guiding portion 500, it is temporarily stored in the oil inclined guiding return portion 600 having an opposite inclination. Therefore, the oil OL does not overflow from the oil outlet inclined guiding portion 500 and the oil inclined guiding return portion 600 to an area other than the oil outlet inclined guiding portion 500 and the oil inclined guiding return portion 600, and can flow into at least one of the first oil guiding groove portion 151 and the second oil guiding groove portion 152 from the oil outlet inclined guiding portion 500 and the oil inclined guiding return portion 600.

[0280] Moreover, the width W2 in the X direction of the oil inclined guiding return portion 600 is set to be larger than the width W1 in the X direction of the oil outlet inclined guiding portion 500. Thus, even if the oil OL separated from the leakage gas BG by the separation unit 330 flows through the oil outlet inclined guiding portion 500 from the upper surface 122 of the impact member 120, the oil inclined guiding return portion 600 can suppress the overflow of the flowing oil OL and sufficiently accommodate the oil OL, and then flow back to the first oil guiding groove portion 151 and the second oil guiding groove portion 152.

[0281] It should be noted that regarding Figure 9(B), as described above, when viewed along the Y direction, the two throttle holes 121, 121 can also be arranged at positions offset from each other in the X direction. In other words, they can also be arranged at positions offset from each other in a direction intersecting the inclination direction of the upper surface 122 of the impact member 120, that is, the flow direction of the oil OL flowing over the upper surface 122 of the impact member 120 (the X direction in the present embodiment). Thereby, it is possible to suppress the oil OL flowing from the upper surface 122 of the impact member 120 toward the oil outlet inclined guide portion 500 from entering the downstream throttle hole 121 among the two throttle holes 121, 121 and clogging the downstream throttle hole 121. Thereby, the action of causing the blow-by gas BG to collide with the collision plate 133 and separating into the oil OL and the gas G can be performed more reliably.

[0282] In Figure 7 , when the engine 1 is tilted forward, the oil OL separated from the blow-by gas BG by the separation portion 330 is released from the filter 130, guided forward in the direction indicated by the X1 direction by the first oil guide groove portion 151, and introduced into the first oil drain port 161 on the front side. Similarly, when the engine 1 is tilted backward, the oil OL separated from the blow-by gas BG by the separation portion 330 is released from the filter 130, guided backward in the X2 direction by the second oil guide groove portion 152, and introduced into the second oil drain port 162 on the rear side.

[0283] The oil OL guided by the first oil guide groove portion 151 to the first oil drain port 161 is discharged into the engine 1 through the check valve provided in the first oil drain port 161 after being temporarily stored in the first oil drain port 161. Similarly, the oil OL guided by the second oil guide groove portion 152 to the second oil drain port 162 is discharged into the engine 1 through the check valve provided in the second oil drain port 162 after being temporarily stored in the second oil drain port 162. The oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is recovered in the oil pan 7, for example, through the oil return path 99 from inside the cover 4.

[0284] In the blow-by gas treatment device 100 and the engine 1 according to the present embodiment, the separation portion 330 is provided to be inclined in the direction in which the oil OL separated from the blow-by gas BG by the separation portion 330 is introduced into the first oil guide groove portion 151 and the second oil guide groove portion 152. Therefore, the oil OL separated from the blow-by gas BG by the separation portion 330 does not stay in the separation portion 330 but is introduced into the first oil guide groove portion 151 and the second oil guide groove portion 152. Thereby, the blow-by gas treatment device 100 of the present embodiment can suppress the retention of the oil OL contained in the blow-by gas BG and can suppress the condensation of the moisture contained in the oil OL at low temperatures. Thereby, the action of separating the blow-by gas BG into the oil OL and the gas G by the separation portion 330 can be performed more reliably.

[0285] In addition, while the impinging member 120 causes the flow rate of the leaking gas BG to increase along a direction inclined with respect to the vertical direction (up-and-down direction), the impinging member 120 causes the leaking gas BG to collide with the collision plate 133. Thereby, the leaking gas BG is reliably separated into oil OL and gas G. Then, at the collision plate 133, the oil OL separated from the leaking gas BG passes through the filter 130 and falls onto the upper surface 122 of the impinging member 120 facing the collision plate 133. Here, the upper surface 122 of the impinging member 120 is inclined downward toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152. Therefore, the oil OL that has fallen onto the upper surface 122 of the impinging member 120 flows on the upper surface 122 of the impinging member 120 due to its own weight and is introduced into the first oil guiding groove portion 151 and the second oil guiding groove portion 152. Thereby, the leaking gas treatment device 100 of the present embodiment can more reliably suppress the retention of the oil OL contained in the leaking gas BG, and can more reliably suppress the condensation of the moisture contained in the oil OL at low temperatures.

[0286] In addition, the setting portion 400 on which the filter 130 is placed projects outward from the upper surface 122 of the impinging member 120, forming an oil guiding gap region 401 that is a space between the impinging member 120 and the filter 130. Then, the oil OL separated from the leaking gas BG by the separating portion 330 flows along the upper surface 122 of the impinging member 120 in the oil guiding gap region 401. Thereby, it is possible to more reliably suppress the retention of the oil OL separated from the leaking gas BG on the upper surface 122 of the impinging member 120, and the oil OL separated from the leaking gas BG is more reliably introduced from the oil guiding gap region 401 formed between the impinging member 120 and the filter 130 toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152.

[0287] In addition, the inclination angle θ1 of the oil outlet inclined guiding portion 500 with respect to the horizontal plane is greater than the inclination angle θ of the upper surface 122 of the impinging member 120 with respect to the horizontal plane. Thereby, the oil outlet inclined guiding portion 500 can quickly introduce the oil OL separated from the leaking gas BG by the separating portion 330 and flowing along the upper surface 122 of the impinging member 120 into the first oil guiding groove portion 151 and the second oil guiding groove portion 152. In addition, it is possible to suppress the retention of the oil OL near the upper surface 122 of the impinging member 120, and to suppress the oil OL separated from the leaking gas BG by the separating portion 330 from mixing into the leaking gas BG again.

[0288] Furthermore, in the blow-by gas treatment device 100 according to the present embodiment and the engine 1 having the blow-by gas treatment device 100, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided to the front side of the engine 1 by the first oil guiding groove portion 151, and after being temporarily stored in the first oil drain port 161, it is discharged into the engine 1. In addition, the oil OL separated from the blow-by gas BG by the separation unit 330 is guided to the rear side of the engine 1 by the second oil guiding groove portion 152, and after being temporarily stored in the second oil drain port 162, it is discharged into the engine 1. Therefore, in the blow-by gas treatment device 100 of the present embodiment, the discharge path of the oil OL separated from the blow-by gas BG by the separation unit 330 is clear. In addition, the gas G after the oil OL is separated from the blow-by gas BG is introduced by the main structural portion 101 to the outlet portion 40 of the blow-by gas treatment device 100. Then, the outlet portion 40 of the blow-by gas treatment device 100 supplies the gas G introduced by the main structural portion 101 to the intake system of the engine 1. In this way, in the blow-by gas treatment device 100 of the present embodiment, the discharge path of the oil OL separated from the blow-by gas BG by the separation unit 330 and the discharge path of the gas G separated from the blow-by gas BG by the separation unit 330 are clearly distinguished. Thereby, even if the engine 1 tilts in the front-rear direction, it is possible to suppress the oil OL separated from the blow-by gas BG from being released from the outlet portion 40. In addition, since it is possible to suppress the oil OL mist from flowing through the intake system, it is possible to suppress the oil OL mist combustion and achieve the purification of the exhaust gas.

[0289] In addition, the separation unit 330 that separates the blow-by gas BG into the oil OL and the gas G is provided at the central position RP, that is, the central portion between the first oil drain port 161 that temporarily stores the oil OL guided by the first oil guiding groove portion 151 and discharges it into the engine 1 and the second oil drain port 162 that temporarily stores the oil OL guided by the second oil guiding groove portion 152 and discharges it into the engine 1. In this way, the separation unit 330 is provided at a position far from the first oil drain port 161 and the second oil drain port 162. Therefore, even if the engine 1 tilts in the front-rear direction, it is possible to suppress the oil OL temporarily stored in the first oil drain port 161 and the second oil drain port 162, the oil OL existing above the first oil drain port 161 and the second oil drain port 162, and the oil OL mist from being involved in the gas G separated from the blow-by gas BG by the separation unit 330 or being remixed. Thereby, even if the engine 1 tilts in the front-rear direction, it is possible to further suppress the oil OL separated from the blow-by gas BG from being released from the outlet portion 40.

[0290] In addition, since it is possible to suppress the oil OL and the mist of the oil OL from being involved in the gas G separated from the blow-by gas BG by the separation unit 330 or remixed, it is possible to suppress the release of the oil OL separated from the blow-by gas BG from the outlet unit 40 regardless of the position of the outlet unit 40. As a result, the degree of freedom in selecting the installation position and installation direction of the outlet unit 40 can be increased.

[0291] Since the first oil guiding groove portion 151 and the second oil guiding groove portion 152 are in a groove shape, a simple structure can be achieved, and even when the engine 1 is tilted in the front-rear direction, the oil OL separated from the blow-by gas BG by the separation unit 330 can be reliably guided to the front side and the rear side of the engine 1.

[0292] In addition, in the blow-by gas treatment device 100 according to the present embodiment, the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 for taking in the blow-by gas BG and the first oil guiding groove portion 151 and the second oil guiding groove portion 152 for guiding the oil OL are separately provided on both the upper surface side and the lower surface side via a common partition wall portion 200. Therefore, the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 and the first oil guiding groove portion 151 and the second oil guiding groove portion 152 can be provided in the partition wall portion 200 as one member. Therefore, the vertical dimension V of the blow-by gas treatment device 100 can be suppressed (refer to Figure 7 ). Therefore, the height dimension of the cover 4 in which the blow-by gas treatment device 100 is arranged can be suppressed, and the height dimension of the engine 1 having the blow-by gas treatment device 100 in the cover 4 can be suppressed.

[0293] In addition, after the flow rate of the blow-by gas BG is increased by the impact member 120, the blow-by gas BG collides with the collision plate 133 through the filter 130. Therefore, the blow-by gas BG is more reliably separated into the oil OL and the gas G from which the mist of the oil OL has been removed. In addition, the impact member 120 causes the flow rate of the blow-by gas BG to rise in a direction inclined with respect to the vertical direction (up and down direction) at the central position RP in the front-rear direction of the engine 1. In addition, the collision plate 133 extends in a substantially horizontal direction and causes the blow-by gas BG that has passed through the filter 130 to collide therewith. Therefore, compared with the case where the impact member causes the flow rate of the blow-by gas to rise along the horizontal direction and the blow-by gas collides with the collision plate extending in the vertical direction, the vertical dimension V of the blow-by gas treatment device 100 can be suppressed.

[0294] Next, a fourth embodiment of the present invention will be described.

[0295] It should be noted that when the components of the blow-by gas treatment device in the fourth embodiment are the same as those of the blow-by gas treatment devices in the first, second, and third embodiments, the repeated descriptions will be appropriately omitted. Hereinafter, the description will focus on the differences.

[0296] The main part of the structure of the blow-by gas treatment device in the fourth embodiment is the same as Figure 7 the main part of the structure of the blow-by gas treatment device in the third embodiment described above.

[0297] Here, with reference to Figures 10 to 11 the structure example of the separation unit 330 as the center for explanation.

[0298] Figure 10 is a perspective view showing the separation unit of the blow-by gas treatment device of this embodiment.

[0299] Figure 11 is Figure 10 a cross-sectional view of the cutting plane B-B shown.

[0300] Figure 10 The separation unit 330 shown is also called an impactor type separator and has an impactor 120, a filter 130, and a collision plate 133, and is disposed between the first blow-by gas intake portion 111 and the second blow-by gas intake portion 112 in the front-rear direction of the engine 1. More specifically, the separation unit 330 is disposed at the central position RP, which is the central portion between the first oil drain port 161 and the second oil drain port 162 in the front-rear direction of the engine 1.

[0301] The impactor 120 has the function of a nozzle or an orifice. The orifice 121 of the impactor 120 is a so-called longitudinal orifice in which the direction of the axis 121C is along the Z direction, that is, the vertical direction or the up-down direction. The impactor 120 is a flow velocity increasing operation unit that can increase the flow velocity of the blow-by gas BG by causing the blow-by gas BG to pass upward along the orifice 121. The impactor 120 is disposed at the central position RP in the X direction of the partition wall portion 200. Thus, the blow-by gas BG taken in by the first blow-by gas intake portion 111 and the blow-by gas BG taken in by the second blow-by gas intake portion 112 are uniformly guided to the impactor 120. On the basis of increasing the flow velocity of the blow-by gas BG flowing into the orifice 121, the impactor 120 guides the blow-by gas BG to the filter 130. It should be noted that the direction of the axis 121C of the orifice 121 is not limited to the vertical direction or the up-down direction, and may be inclined with respect to the Z direction.

[0302] As Figures 10 to 11As shown, the filter 130 is removably mounted on the partition wall portion 200, i.e., on the setting portions 400, 400 of the impact member 120. The filter 130 is a member for improving the performance of separating oil OL from the leaking gas BG (i.e., the separation performance of oil OL), and is made of, for example, materials such as glass wool and steel wool. However, the material of the filter 130 is not particularly limited. The filter 130 is fixed by mounting screws 139, 139 and is clamped between the collision plate 133 and the setting portions 400, 400 of the impact member 120. That is, the impact member 120 as a flow velocity increasing operation portion is disposed on the lower surface of the filter 130. The collision plate 133 is disposed on the upper surface of the filter 130. The collision plate 133 is, for example, a metal plate and extends in a direction parallel to the upper surface 122 of the impact member 120. The collision plate 133 has, for example, threaded holes 138, 138 through which the two mounting screws 139, 139 pass. The screw 139 of the present embodiment is an example of the "fastening member" of the present invention.

[0303] As Figure 10 and Figure 11 shown, on the upper surface 122 of the impact member 120, convex-shaped setting portions 400, 400 protruding outward from the upper surface 122 of the impact member 120 are provided. The setting portions 400, 400 are portions for tilting the filter 130 and the collision plate 133 downward toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152. Specifically, they are portions for removably fixing the filter 130 and the collision plate 133 in a state of tilting at a specified tilt angle. However, the setting portions 400, 400 do not necessarily tilt the filter 130 and the collision plate 133 downward toward the first oil guiding groove portion 151 and the second oil guiding groove portion 152. The setting portions 400, 400 are formed in a manner of bulging in a circular shape on the upper surface 122 of the impact member 120. The positions of the respective setting portions 400, 400 correspond to the positions of the threaded holes 138, 138 of the collision plate 133. The respective setting portions 400, 400 are provided to be tilted in a direction for guiding the oil OL separated from the leaking gas BG into the first oil guiding groove portion 151 and the second oil guiding groove portion 152 as oil guiding portions.

[0304] As Figure 10 shown, an oil guiding gap region 401 is formed between the two setting portions 400, 400. The oil guiding gap region 401 is a space formed between the upper surface 122 of the impact member 120 and the lower surface 131 of the filter 130. That is, the setting portions 400, 400 form the oil guiding gap region 401 as a space between the upper surface 122 of the impact member 120 and the lower surface 131 of the filter 130. As Figure 11As shown, the throttle hole 121 is provided so as to penetrate through a part of the impact member 120 in the oil guiding clearance region 401. The throttle hole 121 of the impact member 120 causes the flow velocity of the leaking gas BG to rise upward and supplies it to the filter 130. Internal thread portions 402 are respectively provided in the setting portions 400, 400. Each mounting screw 139 passes through the threaded hole 138 of the collision plate 133 and the filter 130, and is fastened to the internal thread portion 402 of the setting portion 400. Thus, the filter 130 is detachably fixed between the collision plate 133 and the setting portion 400 of the impact member 120. In other words, by fastening the screw 139 to the internal thread portion 402 provided in the setting portion 400, the filter 130 is held between the collision plate 133 and the setting portion 400 of the impact member 120.

[0305] Here, when considering the prevention of the filter 130 from falling off and the improvement of the holding performance, as described above, it is preferable to hold the filter 130 using a fastening member such as the screw 139. However, as described above, the filter 130 is made of, for example, materials such as glass wool and steel wool. Therefore, when only using the fastening member to hold the filter 130, the amount of deformation of the filter 130 varies according to the torque of the fastening member. In this way, the shape of the filter 130 becomes unstable. Thus, when only using the fastening member to hold the filter 130, the separation performance of the oil OL becomes unstable.

[0306] In response to this, as Figure 10 and Figure 11 shown, in the leaking gas processing device 100 of the present embodiment, the deformation suppressing member 140 is disposed between the setting portion 400 of the impact member 120 and the collision plate 133. The deformation suppressing member 140 is formed of, for example, metal and suppresses the deformation of the filter 130 due to the fastening of the screw 139. The deformation suppressing member 140 is a cylindrical member having a hole 141. Here, in the present application specification, the "cylindrical member" is not limited to a member in which the cross-sectional shape of the hole in the direction perpendicular to the length direction of the member is circular, and may include a member in which the cross-sectional shape of the hole in the direction perpendicular to the length direction of the member is a polygon such as a triangle, a quadrilateral, a pentagon, and a hexagon. In Figure 10 as an example of the deformation suppressing member 140, a member of a cylinder having a hole 141 with a circular cross-sectional shape can be cited. However, the example of the deformation suppressing member 140 is not limited to this, and it may also be a member of a square cylinder having a hole with a polygonal cross-sectional shape. As Figure 11 shown, the axis of the hole 141 of the deformation suppressing member 140 and the axis of the threaded hole 138 provided in the collision plate 133 and the axis of the internal thread portion 402 provided in the setting portion 400 are substantially on the same straight line. Then, the hole 141 of the deformation suppressing member 140 passes through the shaft portion 139b of the screw 139.

[0307] That is, asFigure 11 As shown, the screw 139 has a shaft portion 139b fastened to the internal thread portion 402 of the setting portion 400 provided in the impact member 120, and a head portion 139a provided at one end of the shaft portion 139b. Moreover, as Figure 11 shown, the deformation suppression member 140 is disposed between the setting portion 400 of the impact member 120 and the head portion 139a of the screw 139 in a state where the shaft portion 139b of the screw 139 passes through the hole 141.

[0308] As Figure 11 shown, the deformation suppression member 140 uses the end portions 142 and 143 of the cylindrical member to withstand the force F1 transmitted from the head portion 139a of the screw 139 via the collision plate 133 due to the fastening of the screw 139 and the force F2 transmitted from the setting portion 400 of the impact member 120 due to the fastening of the screw 139. Specifically, the deformation suppression member 140 uses one end portion (the upper end portion in Figure 11 ) 142 to withstand the force F1 transmitted from the head portion 139a of the screw 139 via the collision plate 133 due to the fastening of the screw 139. In addition, the deformation suppression member 140 uses the other end portion (the lower end portion in Figure 11 ) 143 to withstand the force F2 transmitted from the setting portion 400 of the impact member 120 due to the fastening of the screw 139. In this way, the deformation suppression member 140 suppresses the deformation of the filter 130 due to the fastening of the screw 139. The length L1 of the deformation suppression member 140 in the axial direction of the hole 141 is equal to the thickness L2 of the filter 130.

[0309] The leakage gas BG flows into the throttle hole 121 of the impact member 120 and rises upward, thereby increasing the flow rate. The leakage gas BG with increased flow rate passes through the filter 130 to remove foreign matters, and collides with the lower surface of the collision plate 133, thereby separating into oil OL and gas G. That is, the collision plate 133 causes the leakage gas BG that has passed through the filter 130 to collide and separate into oil OL and gas G.

[0310] The gas G separated from the leakage gas BG by the separation portion 330 is released from the filter 130. As described above, the guide wall portion 203 is provided between the partition wall portion 200 and the upper surface portion 4A of the cover 4. Therefore, the gas G that is free of oil OL and fog released from the filter 130 is guided by the guide wall portion 203 and passes through the passage 135 in the upper region 4Q, and is introduced into the outlet portion 40.

[0311] On the other hand, the oil OL separated from the blow-by gas BG by the separation part 330 falls through the filter 130 and lands on the upper surface 122 of the impact part 120 in the oil guiding gap area 401. The oil OL that lands on the upper surface 122 of the impact part 120 flows along the upper surface 122 of the impact part 120 in the oil guiding gap area 401 and flows toward the first oil guiding groove part 151 and the second oil guiding groove part 152.

[0312] The separation part 330 having the above structure is located at Figure 7 the central position RP in the X direction shown in the figure, and functions as a converging part that can cause the blow-by gas BG to converge from the front side and the rear side of the engine 1 toward the central part in the X direction. Thus, since the separation part 330 is located at the central position RP in the X direction of the cover 4, the blow-by gas BG can be concentrated from the front side and the rear side to the central part in the X direction within the cover 4 and separated into the oil OL and the oil-free fog gas G.

[0313] Next, the oil outlet inclined guiding part 500 and the oil inclined guiding return part 600 will be described with reference to Figure 10 the figure.

[0314] As Figure 10 shown in the figure, the oil outlet inclined guiding part 500 is provided between the oil guiding gap area 401 and the first oil guiding groove part 151 and the second oil guiding groove part 152. The oil outlet inclined guiding part 500 is connected to the upper surface 122 of the impact part 120 in the oil guiding gap area 401 and the first oil guiding groove part 151 and the second oil guiding groove part 152, and is formed to be inclined in the direction of descending from the upper surface 122 of the impact part 120 toward the first oil guiding groove part 151 and the second oil guiding groove part 152. That is, in order to introduce the oil OL separated from the blow-by gas BG by the separation part 330 and flowing along the upper surface 122 of the impact part 120 into the first oil guiding groove part 151 and the second oil guiding groove part 152 serving as oil guiding parts, the oil outlet inclined guiding part 500 is formed to be inclined in the direction of descending from the upper surface 122 of the impact part 120 toward the first oil guiding groove part 151 and the second oil guiding groove part 152.

[0315] The inclination angle of the oil outlet inclined guiding portion 500 with respect to the horizontal plane (X-Y plane) is preferably greater than the inclination angle of the upper surface 122 of the impact member 120 with respect to the horizontal plane. It should be noted that the upper surface 122 of the impact member 120 does not necessarily have to be inclined with respect to the horizontal plane and may also be parallel to the horizontal plane. When the inclination angle of the oil outlet inclined guiding portion 500 with respect to the horizontal plane is greater than the inclination angle of the upper surface 122 of the impact member 120 with respect to the horizontal plane, when the oil OL separated by the separation portion 330 from the leaking gas BG and flowing along the upper surface 122 of the impact member 120 drops to the oil outlet inclined guiding portion 500, the flow rate of the oil OL becomes faster compared to when the oil OL flows through the upper surface 122 of the impact member 120. Therefore, the oil OL separated from the leaking gas BG by the separation portion 330 can be quickly introduced from the upper surface 122 of the impact member 120 into the first oil guiding groove portion 151 and the second oil guiding groove portion 152. In addition, since the oil OL is not likely to stay on the upper surface 122 of the impact member 120, it is possible to prevent the oil OL separated from the leaking gas BG by the separation portion 330 from mixing into the leaking gas BG again.

[0316] In addition, as Figure 10 shown, when viewed from the first oil guiding groove portion 151 and the second oil guiding groove portion 152, the oil inclined guiding return portion 600 is provided on the side opposite to the oil outlet inclined guiding portion 500. That is, the oil outlet inclined guiding portion 500 is provided on one side of the first oil guiding groove portion 151 and the second oil guiding groove portion 152 (the side where the separation portion 330 is provided), and the oil inclined guiding return portion 600 is provided on the other side of the first oil guiding groove portion 151 and the second oil guiding groove portion 152. The oil inclined guiding return portion 600 is formed to be inclined from the lowermost position of the oil outlet inclined guiding portion 500 in a manner having an inclination opposite to that of the oil outlet inclined guiding portion 500. That is, as Figure 10As illustrated, the oil outlet inclined guide portion 500 and the oil inclined guide return portion 600 are formed in a substantially V shape when viewed in cross section. The inclination angle of the oil inclined guide return portion 600 with respect to the horizontal plane is not particularly limited, and is, for example, set to be approximately the same as or less than the inclination angle of the oil outlet inclined guide portion 500 with respect to the horizontal plane. The inclination angle of the oil inclined guide return portion 600 with respect to the horizontal plane is, for example, about 5 degrees or more and 10 degrees or less. When the inclination angle of the oil inclined guide return portion 600 with respect to the horizontal plane is less than 5 degrees, it is difficult to quickly guide the oil OL temporarily stored or concentrated in the oil inclined guide return portion 600 to the first oil guide groove portion 151 and the second oil guide groove portion 152. In addition, when the inclination angle of the oil inclined guide return portion 600 with respect to the horizontal plane is greater than 10 degrees, the speed at which the oil OL temporarily stored or concentrated in the oil inclined guide return portion 600 is guided to the first oil guide groove portion 151 and the second oil guide groove portion 152 is too fast, resulting in the possibility that the oil OL may return to the oil outlet inclined guide portion 500 on the opposite side.

[0317] When the oil OL separated from the leaking gas BG by the separation portion 330 flows out from the upper surface 122 of the impact member 120 via the oil outlet inclined guide portion 500, in order to prevent the oil OL from flowing out from the oil outlet inclined guide portion 500, the first oil guide groove portion 151, and the second oil guide groove portion 152 due to the flow trend when the oil OL flows out, the oil inclined guide return portion 600 temporarily stores or concentrates the oil OL. Then, the oil inclined guide return portion 600 guides and returns the oil OL to the first oil guide groove portion 151 and the second oil guide groove portion 152. In this way, the oil inclined guide return portion 600 has a temporary oil buffering function or a concentrating function for temporarily storing the oil OL separated from the leaking gas BG by the separation portion 330 and guiding and returning it to the first oil guide groove portion 151 and the second oil guide groove portion 152.

[0318] As Figure 10 shown, the lowermost part of the oil outlet inclined guide portion 500 is connected to the lowermost part of the oil inclined guide return portion 600. The connection position between the oil outlet inclined guide portion 500 and the oil inclined guide return portion 600 extends in the X direction and is located between the first oil guide groove portion 151 and the second oil guide groove portion 152.

[0319] Figure 7The first oil guiding groove portion 151 shown is in a groove shape, is provided from the front portion 4B of the cover 4 to the vicinity of the filter 130, and slopes downward from the filter 130 toward the front portion 4B of the cover 4. Similarly, the second oil guiding groove portion 152 is in a groove shape, is provided from the rear portion 4C of the cover 4 to the vicinity of the filter 130, and slopes downward from the filter 130 toward the rear portion 4C of the cover 4. The first oil guiding groove portion 151 and the second oil guiding groove portion 152 guide the oil OL separated from the blow-by gas BG by the separating portion 330. The first oil guiding groove portion 151 is a specific structural example of the "first oil guiding portion" of the present invention. When Figure 1 the engine 1 tilts forward, the oil OL released from the filter 130 can be guided forward in the direction shown by X1 and introduced into the first oil drain port 161 on the front side. Similarly, the second oil guiding groove portion 152 is a specific structural example of the "second oil guiding portion" of the present invention. When Figure 1 the engine 1 tilts backward, the oil OL released from the filter 130 can be guided backward in the direction shown by X2 and introduced into the second oil drain port 162 on the rear side.

[0320] The first oil guiding groove portion 151 and the second oil guiding groove portion 152 are connected to each other via the above-mentioned oil outlet inclined guiding portion 500 and the oil inclined guiding return portion 600.

[0321] The first oil drain port 161 is provided on the front side of the engine 1 and is, for example, cylindrical. The first oil drain port 161 is provided in the cover 4 in the Z1 direction, that is, downward, at a position in front of the first guiding lower surface portion 231 of the partition wall portion 200. The first oil drain port 161 has a check valve, temporarily stores the oil OL guided by the first oil guiding groove portion 151, and discharges it into the engine 1. Similarly, the second oil drain port 162 is provided on the rear side of the engine 1 and is, for example, cylindrical. The second oil drain port 162 is provided in the cover 4 in the Z1 direction, that is, downward, at a position behind the second guiding lower surface portion 232 of the partition wall portion 200. The second oil drain port 162 has a check valve, temporarily stores the oil OL guided by the second oil guiding groove portion 152, and discharges it into the engine 1.

[0322] Accordingly, when the engine 1 tilts forward, the oil OL separated from the blow-by gas BG by the separating portion 330 is guided by the first oil guiding groove portion 151 in the X1 direction, and after being temporarily stored in the first oil drain port 161, it is discharged in the Z1 direction through the first oil drain port 161. Similarly, when the engine 1 tilts backward, the oil OL separated from the blow-by gas BG by the separating portion 330 is guided by the second oil guiding groove portion 152 in the X2 direction, and after being temporarily stored in the second oil drain port 162, it is discharged in the Z1 direction through the second oil drain port 162. In the cover 4, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162, for example, fromFigure 1 The cover 4 shown is recovered in the oil pan 7 through the above-described oil return path 99. Alternatively, the discharged oil OL can be recovered, for example, in an oil container (not shown). Thus, the oil OL discharged from the first oil drain port 161 and the second oil drain port 162 is discharged into the engine 1 without leaking to the outside of the engine 1.

[0323] As described above, in the blow-by gas treatment device 100 and the engine 1 according to the present embodiment, the filter 130 of the separation unit 330 that separates the blow-by gas BG into the oil OL and the gas G is fastened by the screw 139 to the internal thread portion 402 provided in the setting portion 400 of the impact member 120, and thus is held between the setting portion 400 of the impact member 120 and the collision plate 133. Here, the deformation suppressing member 140 is disposed between the setting portion 400 of the impact member 120 and the collision plate 133. The deformation suppressing member 140 suppresses the deformation of the filter 130 held between the setting portion 400 of the impact member 120 and the collision plate 133 due to the fastening of the screw 139. Thus, when the filter 130 is held by the screw 139, the deformation of the filter 130 can be suppressed. For example, it is possible to suppress the case where the amount of deformation of the filter 130 becomes unstable due to differences in the torque of the screw 139 and the shape of the filter 130. Thus, when the filter 130 is held by the screw 139, stable oil OL separation performance can be achieved.

[0324] In addition, the deformation suppressing member 140 is a cylindrical member having a hole 141 through which the shaft portion 139b of the screw 139 passes. Moreover, in a state where the shaft portion 139b of the screw 139 passes through the hole 141 of the deformation suppressing member 140, the deformation suppressing member 140 is disposed between the setting portion 400 of the impact member 120 and the head 139a of the screw 139. Therefore, the deformation suppressing member 140 can withstand the forces F1 and F2 transmitted from the setting portion 400 of the impact member 120 and the head 139a of the screw 139 due to the fastening of the screw 139 between the setting portion 400 of the impact member 120 and the head 139a of the screw 139. Therefore, the deformation suppressing member 140 can more reliably suppress the case where the filter 130 held between the setting portion 400 of the impact member 120 and the collision plate 133 is deformed due to the fastening of the screw 139. Thus, when the filter 130 is held by the screw 139, stable oil OL separation performance can be more reliably achieved.

[0325] In addition, the deformation suppressing member 140 uses one end (the upper end in Figure 11 in this case) 142 to withstand the force F1 transmitted from the head 139a of the screw 139 via the collision plate 133 due to the fastening of the screw 139, and uses the other end (in Figure 11The lower end portion 143 of the middle part bears the force F2 transmitted from the setting portion 400 of the impact member 120 due to the fastening of the screw 139. Therefore, the deformation suppression member 140 can use one end portion 142 to bear the force transmitted from the head 139a of the screw 139, that is, the force F1 that is relatively homogenized through the collision plate 133. Therefore, the deformation suppression member 140 can more reliably suppress the deformation of the filter 130 held between the setting portion 400 of the impact member 120 and the collision plate 133 due to the fastening of the screw 139. Thus, when the filter 130 is held by the screw 139, the stable separation performance of the oil OL can be more reliably achieved.

[0326] In addition, the length L1 of the hole 141 of the deformation suppression member 140 in the axial direction is equal to the thickness L2 of the filter 130. Therefore, the deformation suppression member 140 can suppress the filter 130 from being flattened to a length shorter than the length L1 of the hole 141 of the deformation suppression member 140 in the axial direction. Therefore, it is possible to more reliably suppress the difference in the amount of deformation of the filter 130 due to the torque of the screw 139. Thus, when the filter 130 is held by the screw 139, the stable separation performance of the oil OL can be achieved.

[0327] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the scope of the patent claims. The structure of the above embodiments can omit a part thereof, or can be arbitrarily combined in a manner different from the above.

[0328] For example, as an example of the engine of the present invention, the engine 1 of the present embodiment is exemplified. The engine 1 is a supercharged diesel engine with a turbocharger. However, it is not limited thereto, and the engine of the present invention can also be a naturally aspirated diesel engine, a supercharged gasoline engine with a turbocharger, a naturally aspirated gasoline engine, etc. In addition, the type of the illustrated engine 1 is, for example, a supercharged high-output three-cylinder engine, a multi-cylinder engine such as a four-cylinder engine, etc. with a turbocharger. However, the type of the engine 1 is not limited thereto. The engine 1 can be mounted on vehicles other than those of the types such as construction machinery, agricultural machinery, and lawn mowers. In addition, in the description of the present embodiment, the first oil guiding portion is exemplified by the first oil guiding groove portion 151, and the second oil guiding portion is exemplified by the second oil guiding groove portion 152. However, the first oil guiding portion and the second oil guiding portion are not limited thereto, and can also be, for example, tubular members.

[0329] For example, in the present embodiment, the case where the deformation suppression member 140 is a cylindrical member is taken as an example for illustration. However, the deformation suppression member 140 is not limited to being a cylindrical member. For example, it may also be a semi-cylindrical member obtained by cutting a cylindrical member in half along the axis of the hole 141. In addition, in the present embodiment, the case where two deformation suppression members 140 are provided is taken as an example for illustration. However, the number of deformation suppression members 140 provided is not limited to two, and may be one, or three or more.

[0330] Description of Reference Numerals

[0331] 1: Engine; 2: Cylinder block; 3: Cylinder head; 4: Valve cover; 4A: Upper part; 4B: Front part; 4C: Rear part; 4D: Left and right side parts; 4P: Lower region; 4Q: Upper region; 4R: Upper region; 5: Cylinder; 6: Crankcase; 7: Oil pan; 8: Piston; 9: Crankshaft; 10: Connecting rod; 11: Valve cam chamber; 12: Valve camshaft; 13: Tappet; 14: Tappet guide hole; 15: Push rod; 16: Insert through hole; 17: Rocker arm; 18: Spring; 19: Intake valve; 20: Exhaust valve; 21: Oil outflow hole; 22: Oil drop hole; 30: Intake passage; 31: Exhaust passage; 40: Outlet part; 41: Pipe; 50: Intake pipe; 50T: Connecting pipe; 52: Air cleaner; 60: Turbocharger; 61: Blower; 62: Turbine; 70: Blow-by gas mixing joint; 71: Main pipe; 72: Sub pipe; 99: Oil return path; 100: Blow-by gas treatment device; 101: Main structural part; 111: First blow-by gas intake part; 112: Second blow-by gas intake part; 120: Impact member; 121: Throttle hole; 121C: Shaft; 122: Upper surface; 130: Filter; 131: Lower surface; 133: Collision plate; 135: Passage; 138: Threaded hole; 139: Screw; 139a: Head; 139b: Shaft part; 140: Deformation suppression member; 141: Hole; 142: End; 143: End; 151: First oil guide groove part; 152: Second oil guide groove part; 161: First oil drain port; 162: Second oil drain port; 200: Partition wall part; 203: Guide wall part; 231: First guide lower surface part; 232: Second guide lower surface part; 295: Guide plate; 330: Separation part; 350: Pressure regulating valve; 400: Setting part; 401: Oil guide clearance area; 402: Internal thread part; 500: Oil outlet inclined guide part; 600: Oil inclined guide return part; 601: Step; 680: Through hole; 681: Inner peripheral surface; 700: Outlet mounting part; 702: Upper surface; 720: Internal space; 721: Internal space; 730: Fitting surface; 740: Oil guide inclined surface; 741: Upper end; 742: Lower end; 745: Sealing member; 750: Container body; 751: Screw; 770: Fitting surface; AR: Intake; B: Inhaled air; BG: Blow-by gas; C: Inhaled air; F1: Force; F2: Force; G: Gas; OL: Oil; RP: Central position; S: Cross-connection position.

Claims

1. A blow-by gas treatment device for treating blow-by gas generated in an engine, characterized in that: It has: A main structural part, which is arranged in the valve cover of the engine, takes in and guides the blow-by gas, and separates the oil contained in the blow-by gas from the blow-by gas; And An outlet part, which supplies the gas, that is, the gas introduced from the main structural part, after separating the oil from the blow-by gas through the main structural part, to the intake system of the engine; The main structural part has: A first blow-by gas intake part, which is arranged on the front side of the engine and is used to take in the blow-by gas; A second blow-by gas intake part, which is arranged on the rear side of the engine and is used to take in the blow-by gas; A separation part, which is arranged between the first blow-by gas intake part and the second blow-by gas intake part in the front-rear direction of the engine, and separates the blow-by gas taken in by the first blow-by gas intake part and the second blow-by gas intake part into the oil and the gas; A first oil guiding part, which is arranged towards the front side from the separation part, and guides the oil separated from the blow-by gas by the separation part towards the front side; A second oil guiding part, which is arranged towards the rear side from the separation part, and guides the oil separated from the blow-by gas by the separation part towards the rear side; A first oil drain port, which is arranged on the front side, temporarily stores the oil guided by the first oil guiding part and discharges it into the engine; A second oil drain port, which is arranged on the rear side, temporarily stores the oil guided by the second oil guiding part and discharges it into the engine; And A partition wall part, which is horizontally arranged along the front-rear direction, The first blow-by gas intake part and the second blow-by gas intake part are arranged on the lower surface side of the partition wall part, The first oil guiding part and the second oil guiding part are arranged on the upper surface side of the partition wall part.

2. The blow-by gas treatment device according to claim 1, characterized in that: The separation part is arranged at the central part between the first oil drain port and the second oil drain port in the front-rear direction.

3. The blow-by gas treatment device according to claim 1 or 2, characterized in that: The first oil guiding part and the second oil guiding part are in a groove shape.

4. The blow-by gas treatment device according to claim 1 or 2, characterized in that: The separation part has: A flow velocity increasing operation part, which makes the flow velocity of the blow-by gas rise along the vertical direction; A filter, through which the blow-by gas with the flow velocity increased by the flow velocity increasing operation part passes; and A collision plate, which extends in the horizontal direction, makes the blow-by gas passing through the filter collide, and separates it into the oil and the gas.

5. The blow-by gas treatment device according to claim 1, characterized in that: The outlet part has an oil guiding surface, which is used to guide the remaining oil in the gas after separating the oil from the blow-by gas into the valve cover.

6. The blow-by gas treatment device according to claim 5, characterized in that: The outlet part has: An outlet mounting portion, disposed on the upper part of the cover, having a through hole for the gas to pass through; and A container body, disposed on the outlet mounting portion, temporarily accommodating the gas that has passed through the through hole, and supplying it to the intake system, The oil guiding surface is an oil guiding inclined surface that slopes downward from the mating surface between the outlet mounting portion and the container body toward the through hole.

7. The leakage gas treatment device according to claim 6, wherein The oil guiding inclined surface is formed in the entire area from the mating surface to the inner surface of the through hole.

8. The leakage gas treatment device according to claim 6 or 7, wherein The oil guiding inclined surface is a part of the surface of a cone.

9. The leakage gas treatment device according to any one of claims 5 to 7, wherein It further has: A guiding wall portion, disposed inside the cover, guiding the gas separated from the leakage gas to the outlet portion; and The oil guided from the outlet portion to the inside of the cover by the oil guiding surface flows through the guiding wall portion and is introduced into at least one of the first oil guiding portion and the second oil guiding portion.

10. The leakage gas treatment device according to claim 1, wherein The separation portion is disposed to be inclined in a direction of introducing the oil separated from the leakage gas by the separation portion into the first oil guiding portion and the second oil guiding portion.

11. The leakage gas treatment device according to claim 10, wherein The separation portion has: A flow velocity increasing operation portion, increasing the flow velocity of the leakage gas along a direction inclined with respect to the vertical direction; A filter, allowing the leakage gas whose flow velocity has been increased by the flow velocity increasing operation portion to pass through; and A collision plate, causing the leakage gas that has passed through the filter to collide and separating it into the oil and the gas, The surface of the flow velocity increasing operation portion facing the collision plate slopes downward toward the first oil guiding portion and the second oil guiding portion.

12. The leakage gas treatment device according to claim 1, wherein The separation portion has: A flow velocity increasing operation portion, increasing the flow velocity of the leakage gas; A filter, allowing the leakage gas whose flow velocity has been increased by the flow velocity increasing operation portion to pass through; A collision plate, causing the leakage gas that has passed through the filter to collide and separating it into the oil and the gas; A fastening member, fastened to the flow velocity increasing operation portion and holding the filter between the flow velocity increasing operation portion and the collision plate; And A deformation suppressing member, disposed between the flow velocity increasing operation portion and the collision plate, suppressing deformation of the filter due to the fastening of the fastening member.

13. The leakage gas treatment device according to claim 12, wherein The fastening member has: A shaft portion, fastened to the flow velocity increasing operation portion; And A head portion, disposed at one end of the shaft portion, The deformation suppressing member is a cylindrical member having a hole for the shaft portion to pass through, and is disposed between the flow velocity increasing operation portion and the head portion in a state where the shaft portion has passed through the hole.

14. An engine, characterized in that it is provided with the blow-by gas treatment device according to any one of claims 1 to 13.

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