JP2018080671A - Internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent inflow of oil into a gas outlet port in a dry sump type internal combustion engine.SOLUTION: A dry sump type internal combustion engine 1 has an oil tank 40 including a main chamber 43A extending in a vehicle fore and aft direction and a sub chamber 43B extending in a vehicle lateral direction from one end in a fore and aft direction of the main chamber. The oil tank has: an inlet port 55 provided at an upper part of a wall part defining the main chamber and connected to scavenging pumps 62, 65; a gas outlet port 68 provided at an upper part of the wall part defining the sub chamber and connected to an intake system; and an oil outlet port 51 provided at a lower part of the wall part defining the main chamber and connected to a feed pump. The sub chamber is formed having a depth shallower than the main chamber.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a dry sump type internal combustion engine.

  A dry sump type internal combustion engine for automobiles is known in which oil collected in the lower part of the crankcase is sent to an oil tank (reservoir tank) separated from the crankcase by a scavenge pump (for example, Patent Document 1). Compared to a wet sump type internal combustion engine with a shallow oil pan at the bottom of the crankcase, the dry sump type internal combustion engine can deepen the oil tank and keep the oil suction port below the oil level. There is an advantage that it is easy.

Japanese Patent Laying-Open No. 2015-113820

  Since blow-by gas flows into the oil tank together with oil from the internal combustion engine body, the oil tank is provided with a gas outlet port for returning the blow-by gas to the intake device. The gas outlet port is provided in the upper part of the oil tank in order to avoid the inflow of oil. However, when the vehicle is accelerating / decelerating or turning, the oil level may be inclined by the inertial force, and the oil level may approach the gas outlet port. Therefore, a structure that reliably prevents the oil from flowing into the gas outlet port is required.

  In view of the above background, an object of the present invention is to prevent oil from flowing into a gas outlet port in a dry sump type internal combustion engine.

  In order to solve the above-described problem, an aspect of the present invention is a dry sump type internal combustion engine, which extends in a vehicle front-rear direction and a main chamber extending in the vehicle front-rear direction and from one end of the main chamber in the vehicle front-rear direction. An oil tank including a sub chamber; and the oil tank is provided at an upper portion of a wall portion defining the main chamber, and is provided with an inlet port connected to a scavenge pump and an upper portion of the wall portion defining the sub chamber. A gas outlet port provided to be connected to the intake device, and an oil outlet port provided at a lower portion of a wall portion defining the main chamber and connected to a feed pump, wherein the sub chamber is the main chamber It is characterized by being formed with a shallow depth.

  According to this aspect, since the gas outlet port is provided in the upper part of the sub chamber that extends from the main chamber to the left and right, the oil is supplied to the gas outlet port even when the oil in the main chamber moves back and forth due to acceleration / deceleration of the vehicle. It becomes difficult to reach.

  Further, in the above aspect, the inlet port is provided on an upper wall that defines an end of the main chamber on the side opposite to the sub chamber, and the gas outlet port is opposite to the main chamber of the sub chamber. It is good to be provided in the upper wall which demarcates the edge part on the side to perform.

  According to this aspect, since the gas and oil inlet port and the gas outlet port are spaced apart, the oil from the blowby gas is separated while the blowby gas flows from the inlet port to the gas outlet port.

  In the above aspect, the oil tank may include a plurality of baffle plates that protrude downward from a lower surface of an upper wall that defines the sub chamber.

  According to this aspect, oil is removed from the blow-by gas flowing from the inlet port to the gas outlet port by the baffle plate. In addition, the oil stored in the main chamber is difficult to move to the sub chamber, and the oil level is difficult to approach the gas outlet port.

  In the above aspect, at least one of the baffle plates may have a portion extending in a substantially horizontal direction.

  According to this aspect, the portion of the baffle plate that extends in the substantially horizontal direction suppresses the inclination and turbulence of the oil level, making it difficult for the oil level to reach the gas outlet port.

  Further, in the above aspect, the engine further includes an internal combustion engine body disposed so that a cylinder axis is substantially horizontal, and the inlet port is connected to the crank chamber and the valve chamber of the internal combustion engine body via the scavenge pump. It is good to be connected to each.

  According to this aspect, the oil is recovered from the crank chamber and the valve operating chamber into the oil tank.

  In the above aspect, the internal combustion engine body includes a cylinder block and a cylinder head, a transmission is coupled to a side surface of the cylinder block, and the oil tank includes at least one of the cylinder block and the cylinder head. The transmission may be coupled to the transmission.

  According to this aspect, the oil tank functions as a reinforcing member that connects at least one of the cylinder block and the cylinder head and the transmission.

  Further, in the above aspect, the internal combustion engine main body extends back and forth from the cylinder block to the cylinder head, the transmission projects to the left and right sides with respect to the cylinder block, and the oil tank includes the cylinder block or It is good to arrange | position in the left-right side of the said cylinder head, and the front or back of the said transmission. The oil tank may be coupled to the transmission at a side wall portion defining the main chamber, and coupled to the cylinder block or the cylinder head at a side wall portion defining the sub chamber.

  According to this aspect, the internal combustion engine main body, the transmission, and the oil tank can be arranged in a compact manner.

  According to the above configuration, oil can be prevented from flowing into the gas outlet port in the dry sump type internal combustion engine.

The perspective view of the internal combustion engine which concerns on embodiment Plan view of an internal combustion engine according to an embodiment Explanatory drawing which shows the connection form of the internal combustion engine main body and oil tank which concern on embodiment The perspective view of the oil tank concerning an embodiment The perspective view of the oil tank which concerns on embodiment Sectional drawing of the oil tank which concerns on embodiment

  Embodiments in which the present invention is applied to an internal combustion engine of an automobile will be described below in detail with reference to the drawings.

  As shown in FIGS. 1 and 2, the internal combustion engine 1 is a dry sump engine. The internal combustion engine body 2 includes a cylinder block 3, a cylinder head 4 coupled to the cylinder block 3, a head cover 5 coupled to the cylinder head 4, and a crankcase 6 coupled to the cylinder block 3. The internal combustion engine body 2 is disposed such that the cylinder axis extends substantially horizontally back and forth, and the crankcase 6, the cylinder block 3, the cylinder head 4, and the head cover 5 are disposed in this order from the front side.

  As shown in FIG. 3, the crankcase 6 is formed in a box shape that opens rearward, and is coupled to the front end surface of the cylinder block 3, thereby defining a crank chamber 8 between the crankcase 6 and the cylinder block 3. . The crank chamber 8 communicates with a cylinder 9 formed at the rear portion of the cylinder block 3. A crankshaft 11 and a balancer shaft 12 are provided in the crank chamber 8. The crankshaft 11 and the balancer shaft 12 extend to the left and right, respectively, and are rotatably supported by a bearing (not shown) coupled to the cylinder block 3. The crankshaft 11 is connected to a piston 15 received in the cylinder 9 via a connecting rod 14. The balancer shaft 12 is disposed in front of the crankshaft 11 in the crank chamber 8 and is connected to the crankshaft 11 by a chain transmission mechanism (not shown).

  The cylinder head 4 is formed with a combustion chamber recess 16 that defines a combustion chamber in a portion corresponding to the cylinder 9. The cylinder head 4 has an intake port 17 that extends upward from the combustion chamber recess 16 and opens to the upper surface of the cylinder head 4, and an exhaust port 18 that extends downward from the combustion chamber recess 16 and opens to the lower surface of the cylinder head 4. And are formed. An intake valve is provided at the boundary between the combustion chamber recess 16 and the intake port 17, and an exhaust valve is provided at the boundary between the combustion chamber and the exhaust port 18.

  The head cover 5 is coupled to the rear end surface of the cylinder head 4 and defines a valve operating chamber 24 between the head cover 5 and the cylinder head 4. In the valve operating chamber 24, a valve operating device 25 for opening and closing the intake valve and the exhaust valve is disposed.

  As shown in FIGS. 1 and 2, an intake device 30 communicating with the intake port 17 is provided above the internal combustion engine body 2. The intake device 30 is a device that supplies air to the intake port. For example, the intake device 30 includes an air inlet, an air cleaner, a supercharger, a throttle valve, an intake manifold, and the like from the upstream side, and communicates with the intake port 17 in the intake manifold. Good.

  A transmission 37 is provided on the left side of the cylinder block 3 and the crankcase 6. A transmission housing 37 </ b> A that forms an outer shell of the transmission 37 is coupled to the left side surface of the cylinder block 3 and extends leftward from the cylinder block 3. In plan view, the internal combustion engine body 2 and the transmission housing 37A cooperate to form an L-shaped outer shape.

  As shown in FIGS. 1 and 2, an oil tank 40 is disposed to the left of the cylinder head 4 and behind the transmission housing 37 </ b> A. As shown in FIGS. 4 to 6, the oil tank 40 includes a box-shaped tank main body 41 that opens upward, and a plate-shaped lid 42 that closes the upper opening of the tank main body 41. The tank body 41 and the lid 42 cooperate to define the oil chamber 43. The oil chamber 43 has a main chamber 43A extending in the front-rear direction and a sub chamber 43B extending rightward from the rear end of the main chamber 43A, and has an L shape in plan view. Similarly, the tank body 41 and the lid 42 that define the main chamber 43A and the sub chamber 43B are also formed in an L shape having a portion extending in the front-rear direction and a portion extending in the left-right direction in plan view.

  The tank body 41 includes a main chamber bottom wall 41A that defines the bottom of the main chamber 43A, a main chamber side wall 41B that defines the side of the main chamber 43A, and a sub chamber bottom wall that defines the bottom of the sub chamber 43B. It has a portion 41C and a sub chamber side wall portion 41D that demarcates the side portion of the sub chamber 43B. The lid 42 has a main chamber upper wall portion 42A that defines the upper wall of the main chamber 43A, and a sub chamber upper wall portion 42B that defines the upper wall of the sub chamber 43B.

  As shown in FIGS. 1 and 2, the tank body 41 is coupled to the transmission housing 37A via a connecting member 45 at the front end of the main chamber side wall 41B, and the cylinder head at the right end of the sub chamber side wall 41D. 4 is connected. The oil tank 40 functions as a reinforcing member that couples the transmission housing 37 </ b> A and the cylinder head 4.

  As shown in FIGS. 4 to 6, the main chamber 43A and the sub chamber 43B communicate with each other. The front / rear length of the main chamber 43A is longer than the left / right length of the sub chamber 43B, and the left / right length (width) of the main chamber 43A is longer than the front / rear length (width) of the sub chamber 43B. The average depth of the main chamber 43A is formed deeper than the average depth of the sub chamber 43B. Since the upper ends of the main chamber 43A and the sub chamber 43B are at the same height, the bottom of the main chamber 43A is disposed at a position lower than the bottom of the sub chamber 43B. The volume of the main chamber 43A is formed larger than the volume of the sub chamber 43B. In the main chamber 43A, an intermediate portion in the front-rear direction is formed deeper than the other portions. The bottoms of the main chamber 43A and the sub chamber 43B are smoothly connected, and oil can flow from the sub chamber 43B to the main chamber 43A by gravity.

  An oil outlet port 51 penetrating in the thickness direction is formed at the lowermost portion of the intermediate portion in the front-rear direction of the main chamber side wall 41B. As shown in FIGS. 1 to 3, the oil outlet port 51 is connected to a feed pump 53 provided in the cylinder block 3 via a pipe 52. The feed pump 53 may be, for example, a trochoid pump that is driven by the driving force of the crankshaft 11. The feed pump 53 supplies oil to the sliding portion of the crankshaft 11 and the sliding portion of the valve gear 25 via an oil passage (not shown) formed in the cylinder block 3 and the cylinder head 4.

  As shown in FIGS. 4 to 6, an inlet port 55 penetrating in the thickness direction is formed at an end portion (front end portion) on the side opposite to the sub chamber 43 </ b> B of the main chamber upper wall portion 42 </ b> A. A collecting device 56 is coupled to the upper surface of the main chamber upper wall portion 42 </ b> A so as to communicate with the inlet port 55. The collecting device 56 has a substantially cylindrical case 56A that is closed at the upper end and communicates with the inlet port 55 at the lower end, a first connecting pipe 56B that protrudes tangentially from the outer periphery of the case 56A through the case 56A, and the first connecting pipe 56B. 2 connection pipes 56C. The first connecting pipe 56B and the second connecting pipe 56C are arranged at 180 ° rotationally symmetric positions with respect to the central axis of the case 56A as an axis of symmetry. As shown in FIG. 6, two guide walls 56D projecting radially inward are provided on the inner peripheral surface of the case 56A. The two guide walls 56D are arranged at 180 ° rotationally symmetric positions with respect to the central axis of the case 56A as a symmetric axis, and are respectively provided on the side of the first connecting pipe 56B or the second connecting pipe 56C. The gas flowing into the case 56A from the first connection pipe 56B or the second connection pipe 56C rotates about 90 ° along the inner peripheral wall of the case 56A, and then collides with the guide wall 56D and flows toward the inlet port 55.

  As shown in FIG. 3, the first connection pipe 56 </ b> B is connected to a portion corresponding to the lowermost part of the crank chamber 8 of the crankcase 6 via the pipe 61 and the first scavenge pump 62. The second connection pipe 56C is connected to a portion corresponding to the lowermost part of the valve operating chamber 24 of the cylinder head 4 via the pipe 64 and the second scavenge pump 65. The first scavenge pump 62 and the second scavenge pump 65 may be known trochoid pumps.

  As shown in FIGS. 4 to 6, a gas outlet port 68 penetrating in the thickness direction is formed at an end portion (right end portion) on the side opposite to the main chamber 43 </ b> A of the sub chamber upper wall portion 42 </ b> B. The gas outlet port 68 is connected to the intake device 30 via the PCV valve 69. The PCV valve 69 opens when the pressure on the oil tank 40 side is higher than the pressure on the intake device 30 side, and closes when the pressure on the oil tank 40 side is lower than the pressure on the intake device 30 side.

  An injection port 71 penetrating in the thickness direction is formed at an end portion (rear end portion) of the main chamber upper wall portion 42A on the sub chamber 43B side. The inlet 71 is an opening for replenishing oil, and is closed by a detachable cap 72.

  First to third baffle plates 81 to 83 are coupled to the lower surfaces of the main chamber upper wall portion 42A and the sub chamber upper wall portion 42B. Each of the baffle plates 81 to 83 is formed by bending a metal plate and fastened to the lid 42 with bolts, nuts, and the like.

  The first baffle plate 81 includes a fastening portion 81A fastened to the front end portion of the lower surface of the main chamber upper wall portion 42A, a vertical wall portion 81B that hangs down from the rear end of the fastening portion 81A, and whose surface faces front and rear. It has a horizontal wall part 81C that extends downward from the lower end of the part 81B and whose surface faces up and down. In plan view, the entire area of the inlet port 55 is disposed at a position overlapping the lateral wall portion 81 </ b> C of the first baffle plate 81.

  The second baffle plate 82 includes a first fastening portion 82A fastened to the front side of the inlet 71 at the rear end portion of the lower surface of the main chamber upper wall portion 42A and a second fastening portion fastened to the right side of the inlet 71. 82B, a first vertical wall portion 82C that hangs down from the rear end of the first fastening portion 82A, the surface faces front and back, and a second portion that hangs down from the left end of the second fastening portion 82B, and the surface faces left and right. And a vertical wall portion 82D. The right end of the first vertical wall portion 82C and the front end of the second vertical wall portion 82D are connected to each other and form an L shape in plan view. The front surface of the second baffle plate 82 with the first vertical wall portion 82C and the rear edge of the horizontal wall portion 81C of the first baffle plate 81 are opposed to each other through a minute gap.

  The third baffle plate 83 is disposed at a right distance from the first fastening portion 83A and the first fastening portion 83A fastened to the lower surface of the left end portion of the sub chamber upper wall portion 42B. A second fastening portion 83B fastened to the lower surface of the right end portion of the upper wall portion 42B, a first vertical wall portion 83C hanging from the right end of the first fastening portion 83A and having a surface facing left and right; The second vertical wall portion 83D that hangs down from the left end of the fastening portion 83B and faces to the left and right, and the lower end of the first vertical wall portion 83C and the lower end of the second vertical wall portion 83D are connected to each other downward. A curved wall 83E that is curved in a convex arc shape, a third vertical wall 83F that hangs down from the left end of the first fastening portion 83A, and a surface that faces left and right, and a right end of the second fastening portion 83B. , A third vertical wall 83G whose surface faces left and right, and a horizontal wall that extends rightward from the lower end of the third vertical wall 83G and whose surface faces up and down And a 3H. The first vertical wall portion 83C, the curved wall portion 83E, and the second vertical wall portion 83D cooperate with each other and have a U-shape when viewed from the front and back. The lowermost portion of the curved wall portion 83E extends in a substantially horizontal direction. In plan view, the entire region of the gas outlet port 68 is disposed at a position overlapping the horizontal wall portion 83 </ b> H of the third baffle plate 83.

  At least a portion of the first and second vertical wall portions 82C and 82D of the second baffle plate 82, at least a portion of the first and second vertical wall portions 83C and 83D of the third baffle plate 83, and a curved wall portion 83E is located below the oil level in the oil tank 40 when the internal combustion engine 1 is driven. On the other hand, the lateral wall portion 81 </ b> C of the first baffle plate 81 and the lateral wall portion 83 </ b> H of the third baffle plate 83 are positioned above the oil level in the oil tank 40 when the internal combustion engine 1 is driven.

  When the internal combustion engine 1 is driven, the oil in the oil tank 40 is supplied from the oil outlet to the sliding portion of the crankshaft 11 and the valve operating chamber 24 through the feed pump 53 and the oil passage by the operation of the feed pump 53. The oil supplied to the crankshaft 11 is collected below the crankcase 6 by gravity, and is sent to the first connecting pipe 56B side through the pipe 61 by the operation of the first scavenge pump 62 together with the blow-by gas. Similarly, the oil supplied to the valve operating device 25 is collected below the valve operating chamber 24 by gravity, and is sent to the second connecting pipe 56 </ b> C side via the pipe 64 by the operation of the second scavenge pump 65. The fluid containing oil and blow-by gas supplied into the case 56A of the collecting device 56 from the first connection pipe 56B and the second connection pipe 56C rotates about 90 ° along the inner peripheral wall in the case 56A, and then guide walls It collides with 56D and proceeds downward, passes through the inlet port 55 and flows into the main chamber 43A. At this time, the oil and the blow-by gas are received by the lateral wall portion 81C of the first baffle plate 81 located below the inlet port 55, and the oil flows from the left and right side edges and the rear edge of the lateral wall portion 81C to the oil surface in the oil tank 40. Flows down. The lateral wall portion 81C of the first baffle plate 81 prevents the oil and blow-by gas flowing from the inlet port 55 from directly colliding with the oil surface, and suppresses the generation of bubbles in the stored oil.

  While the blow-by gas that has flowed into the oil tank 40 from the inlet port 55 flows to the gas outlet port 68, part of the oil mist is removed by the second baffle plate 82 and the third baffle plate 83.

  The oil tank 40 has a sub chamber 43B extending rightward from the rear end of the main chamber 43A extending in the front-rear direction, and a gas outlet port 68 is provided in the upper portion of the right end of the sub chamber 43B. The sub chamber 43B is formed shallower than the main chamber 43A, and the volume of oil to be retained is small. Therefore, the oil in the sub chamber 43B moves during acceleration / deceleration or turning of the vehicle, and the oil hardly reaches the gas outlet port 68 even if the oil level is inclined. In addition, when the vehicle accelerates or decelerates or turns, the oil in the main chamber 43A moves and flows into the sub chamber 43B, so that the cross section of the sub chamber 43B is smaller than the cross section of the main chamber 43A. It takes time to reach the port 68. Further, since the movement of oil is inhibited by the second and third baffle plates 82 and 83, it is difficult for the oil to reach the gas outlet port 68.

  The oil tank 40 functions as a reinforcing member that connects the cylinder head 4 and the transmission housing 37 </ b> A, which are disposed on the end sides of the internal combustion engine body 2 and the transmission 37 formed in a substantially L shape in plan view. To do. Further, since the oil tank 40 is disposed on the side of the internal combustion engine body 2 and the transmission 37 that are disposed substantially horizontally, the internal combustion engine body 2, the transmission 37, and the oil tank 40 are substantially rectangular in plan view. It is arranged compactly.

  Although the description of the specific embodiment is finished as described above, the present invention is not limited to the above embodiment and can be widely modified. For example, in the above embodiment, the oil tank 40 is coupled to the transmission housing 37A via the connecting member 45, but the oil tank 40 may be directly coupled to the transmission housing 37A. The oil tank 40 may be coupled to the cylinder block 3 instead of the cylinder head 4.

1: Internal combustion engine 2: Internal combustion engine body 3: Cylinder block 4: Cylinder head 8: Crank chamber 24: Valve operating chamber 25: Valve operating device 30: Intake device 37: Transmission 37A: Transmission housing 40: Oil tank 41: Tank body part 42: Lid 42A: Main chamber upper wall part 42B: Sub chamber upper wall part 43A: Main chamber 43B: Sub chamber 45: Connecting member 51: Oil outlet port 53: Feed pump 55: Inlet port 56: Collecting device 62 : First scavenge pump 65: Second scavenge pump 68: Gas outlet port 71: Inlet port 81: First baffle plate 82: Second baffle plate 83: Third baffle plate

Claims (8)

A dry sump type internal combustion engine,
An oil tank including a main chamber extending in the front-rear direction of the vehicle and a sub-chamber extending in the left-right direction of the vehicle from one end in the front-rear direction of the main chamber;
The oil tank is provided at an upper portion of a wall portion defining the main chamber, and is provided with an inlet port connected to a scavenge pump and an upper portion of the wall portion defining the sub chamber, and a gas connected to an intake device. An outlet port and an oil outlet port provided at a lower portion of a wall portion defining the main chamber and connected to a feed pump;
The internal combustion engine, wherein the sub chamber is formed with a shallow depth with respect to the main chamber. The inlet port is provided on an upper wall that defines an end of the main chamber opposite to the sub chamber,
2. The internal combustion engine according to claim 1, wherein the gas outlet port is provided on an upper wall that defines an end portion of the sub chamber opposite to the main chamber.   The internal combustion engine according to claim 1, wherein the oil tank includes a plurality of baffle plates that protrude downward from a lower surface of an upper wall that defines the sub chamber.   The internal combustion engine according to claim 3, wherein at least one of the baffle plates has a portion extending in a substantially horizontal direction. An internal combustion engine body disposed so that the cylinder axis is substantially horizontal;
The said inlet port is connected to each of the crank chamber and the valve operating chamber of the said internal combustion engine main body via the said scavenge pump, The Claim 1 characterized by the above-mentioned. Internal combustion engine. The internal combustion engine body includes a cylinder block and a cylinder head,
A transmission is coupled to the side of the cylinder block,
The internal combustion engine according to claim 5, wherein the oil tank is coupled to at least one of the cylinder block and the cylinder head and the transmission. The internal combustion engine body extends back and forth from the cylinder block to the cylinder head,
The transmission projects to the left and right sides with respect to the cylinder block,
The internal combustion engine according to claim 6, wherein the oil tank is disposed on the left and right sides of the cylinder block or the cylinder head and in front of or behind the transmission.   The oil tank is coupled to the transmission at a side wall portion defining the main chamber, and is coupled to the cylinder block or the cylinder head at a side wall portion defining the sub chamber. The internal combustion engine described in 1.

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