JP2021017820A - Cooling mechanism - Google Patents

Abstract

To efficiently cool an internal combustion engine by using a simple configuration.SOLUTION: A cooling mechanism includes: a first oil passage 41 provided at least in a connecting rod 6, having one end on which a discharge port 43 discharging oil is formed and having a sliding region 46a in which an inertia body 45 is slidably provided; a first suction port 26 provided on a recessed part 25 formed in the connecting rod 6; and a second oil passage 42 communicated with the first oil passage 41. In the first oil passage 41, a first connection part 47 to which the second oil passage 42 is connected is formed between the sliding region 46a and the discharge port 43. The first oil passage 41 includes a first regulation part 48 provided between the discharge port 43 and the first connection part 47, allowing a flow of oil from the sliding region 46a side to the discharge port 43 side and inhibiting a flow of oil from the discharge port 43 side to the sliding region 46a side. The second oil passage 42 includes a second regulation part 50 allowing a flow of oil from the first suction port 26 side to the first connection part 47 side and inhibiting a flow of oil from the first connection part 47 side to the first suction port 26 side.SELECTED DRAWING: Figure 2

Description

The present invention relates to a cooling mechanism.

Patent Document 1 discloses a cooling device for an internal combustion engine capable of injecting oil supplied into an oil passage inside a connecting rod by an oil pump onto the back surface of a piston.

Japanese Unexamined Patent Publication No. 2018-100638

However, in the method described in Patent Document 1, it is necessary to connect the oil passage inside the connecting rod to the oil pump, and there is a problem that the configuration becomes complicated.

Therefore, an object of the present invention is to provide a cooling mechanism capable of efficiently cooling an internal combustion engine with a simple configuration.

In order to solve the above problems, the cooling mechanism of the present invention has at least a sliding region formed in the connecting rod, a discharge port for discharging oil at one end, and an inertial body slidable. The first oil passage is provided with a first oil passage, a first suction port provided in a recess formed on the outer peripheral surface of the connecting rod, and a second oil passage that communicates with the first oil passage. In the road, a first connection portion to which the second oil passage is connected is formed between the sliding region and the discharge port, and the first oil passage is formed between the discharge port and the first connection portion. A first regulating unit is provided between the two, which allows the flow of oil from the sliding region side to the discharge port side and suppresses the flow of oil from the discharge port side to the sliding region side. The second oil passage allows the flow of oil from the first suction port side to the first connection portion side, and suppresses the flow of oil from the first connection portion side to the first suction port side. It has two regulatory departments.

In addition, a second suction port provided in the recessed portion, a third oil passage that communicates with the first oil passage, and a fourth oil passage that communicates with the second oil passage and the third oil passage. The first oil passage is formed with a second connecting portion to which the third oil passage is connected, and the sliding region is located between the first connecting portion and the second connecting portion. The third oil passage allows the flow of oil from the second suction port side to the second connection portion side, and allows the oil flow from the second connection portion side to the second suction port side. The fourth oil passage has a third regulation part to suppress, and allows the flow of oil from the third oil passage side to the second oil passage side, and allows the oil to flow from the second oil passage side to the third oil passage side. It may have a fourth regulatory section that restricts the flow of oil.

Further, the first suction port is provided at a position closer to the second connection portion than the second suction port, and the second suction port is located closer to the first connection portion than the first suction port. It may be provided in.

According to the present invention, it is possible to efficiently cool an internal combustion engine with a simple configuration.

It is a figure for demonstrating the structure of the engine provided with a cooling mechanism. It is the schematic for demonstrating the cooling mechanism in 1st Embodiment. It is the schematic for demonstrating the cooling mechanism in 2nd Embodiment. It is the schematic for demonstrating the cooling mechanism in 3rd Embodiment. It is the schematic for demonstrating the cooling mechanism in 3rd Embodiment.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, other specific numerical values, and the like shown in the embodiment are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are designated by the same reference numerals to omit duplicate description, and elements not directly related to the present invention are not shown. To do.

(First Embodiment)
FIG. 1 is a diagram illustrating a configuration of an engine 1 provided with a cooling mechanism 40. In the following, the vehicle's traveling direction is forward, the vehicle's backward direction is backward, the right side is right with respect to the vehicle's traveling direction, the left side is left with respect to the vehicle's traveling direction, and the vertical upward direction is upward. The direction and the vertical downward direction will be described as the downward direction. Further, in FIG. 1, for ease of understanding, the cylinder 5 in the left direction and its vicinity are shown in cross section.

As shown in FIG. 1, the internal combustion engine (engine 1) is, for example, a horizontally opposed engine in which cylinders 5 are horizontally arranged with a crankshaft 9 interposed therebetween. The engine 1 is provided with a cylinder block 2, a crankcase 3 integrally formed with the cylinder block 2, and a cylinder head 4 fixed to the cylinder block 2.

The piston 20 is slidably arranged in the cylinder 5 formed in the cylinder block 2. The piston 20 is supported by the connecting rod 6. In the engine 1, a space surrounded by the cylinder head 4, the cylinder 5, and the crown surface 20a of the piston 20 is formed as the combustion chamber 7.

Further, the crankshaft 9 is rotatably supported in the crank chamber 8 formed by the crankcase 3. The connecting rod 6 is rotatably supported by the crankshaft 9. As a result, the piston 20 is connected to the crankshaft 9 via the connecting rod 6.

The cylinder head 4 is formed so that the intake port 10 and the exhaust port 11 communicate with the combustion chamber 7. The intake port 10 has one opening formed on the upstream side of the intake air and two openings on the downstream side of the intake air facing the combustion chamber 7, and the flow path branches into two on the way from the upstream to the downstream. Will be done.

The exhaust port 11 has two openings on the upstream side of the exhaust facing the combustion chamber 7, one opening on the downstream side of the exhaust, and the flow paths merge into one on the way from the upstream to the downstream. To do.

The umbrella portion of the intake valve 12 is located between the intake port 10 and the combustion chamber 7, and the umbrella portion of the exhaust valve 13 is located between the exhaust port 11 and the combustion chamber 7. An intake camshaft 14 to which the cam 14a is fixed and an exhaust camshaft 15 to which the cam 15a is fixed are provided in the cam chamber surrounded by the cylinder head 4 and the head cover (not shown). The intake camshaft 14 and the exhaust camshaft 15 are connected to the crankshaft 9 via a timing chain, and rotate with the rotation of the crankshaft 9.

The cam 14a is in contact with the shaft end of the intake valve 12 via a rocker arm, and is rotated by the intake cam shaft 14 to move the intake valve 12 in the axial direction. As a result, the intake valve 12 opens and closes between the intake port 10 and the combustion chamber 7. The shaft end of the exhaust valve 13 is in contact with the cam 15a via the rocker arm, and the cam 15a is rotated by the exhaust cam shaft 15 to move the exhaust valve 13 in the axial direction. As a result, the exhaust valve 13 opens and closes between the exhaust port 11 and the combustion chamber 7.

The cylinder head 4 is provided with a spark plug (not shown) so that the tip thereof is located in the combustion chamber 7. The air-fuel mixture that has flowed into the combustion chamber 7 through the intake port 10 is ignited by the spark plug at a predetermined timing and burned. Due to such combustion, the piston 20 reciprocates in the cylinder 5, and the reciprocating motion is converted into the rotational motion of the crankshaft 9 through the connecting rod 6.

Three ring grooves 27, 28, and 29 recessed in the radial direction of the piston main body 21 are formed on the outer peripheral surface 21a of the piston main body 21 of the piston 20 in order from the crown surface 20a side. The ring grooves 27, 28, and 29 are formed along the circumferential direction of the piston main body portion 21. The ring grooves 27, 28, and 29 are provided on the outer peripheral surface 21a of the piston main body 21 closer to the crown surface 20a.

The top ring 37 is housed in the ring groove 27. The second ring 38 is housed in the ring groove 28. The oil ring 39 is housed in the ring groove 29.

The top ring 37, the second ring 38, and the oil ring 39 project in the radial direction from the outer peripheral surface 21a of the piston main body 21 in a state of being accommodated in the ring grooves 27, 28, and 29, and come into contact with the cylinder 5. The top ring 37 and the second ring 38 eliminate the gap between the cylinder 5 and the side surface of the piston body 21, and maintain the airtightness of the combustion chamber 7. The oil ring 39 scrapes out excess oil from the inner wall surface of the cylinder 5 to form an appropriate oil film between the cylinder 5 and the outer peripheral surface 21a of the piston body 21, and lubricates the sliding of the piston body 21. To do.

FIG. 2 is a schematic view for explaining the cooling mechanism 40 in the first embodiment. The white arrows in FIG. 2 indicate the direction in which the oil flows. FIG. 2A shows a schematic cross-sectional view of the cooling mechanism 40. As shown in FIG. 2A, the piston 20 is provided with a piston main body 21 formed in a bottomed cylindrical shape having a space formed inside. In the internal space of the piston main body 21, a piston boss 22 is provided continuously with the piston main body 21.

Further, a piston pin hole 23 is formed in the piston boss portion 22. The piston pin hole 23 is formed along a direction orthogonal to the central axis of the piston body 21. A piston pin 24 for connecting the piston 20 and the connecting rod 6 is inserted into the piston pin hole 23. In the present embodiment, the piston pin 24 is press-fitted into the piston pin hole 23, and the relative positions of the piston pin 24 and the piston 20 are fixed. On the other hand, the relative positions of the piston pin 24 and the connecting rod 6 are not fixed, and the connecting rod 6 is smoothly connected to the piston pin 24.

Further, a recess 25 for storing oil is provided on the outer peripheral surface of the connecting rod 6. The recessed portion 25 is formed so that a part of the connecting rod 6 on the upper surface side is cut out. Further, the recessed portion 25 is provided with a first suction port 26 that opens on the outer peripheral surface of the connecting rod 6. The position where the first suction port 26 is provided is not particularly limited as long as it is inside the recess 25, but it is preferably provided at the right end of the recess 25. When the engine 1 is operating, the oil stored in the oil pan (not shown) is agitated by the rotation of the crankshaft 9, and the agitated oil is scattered in the crank chamber 8. Then, a part of the oil scattered in the crank chamber 8 is stored in the recess 25.

FIG. 2B shows a right side view of the cooling mechanism 40. Note that FIG. 2B shows a state in which the connecting rod 6 is not connected to the piston 20. As shown in FIGS. 2A and 2B, the cooling mechanism 40 includes a first oil passage 41. Further, as shown in FIG. 2A, the first oil passage 41 is formed over the connecting rod 6 and the piston pin 24. A discharge port 43 for discharging oil is formed at one end of the first oil passage 41, and an air hole 44 is formed at the other end side of the first oil passage 41. The discharge port 43 opens at the tip on the left side of the connecting rod 6 so as to face the back surface of the crown surface 20a of the piston 20.

Further, an inertial body 45 is inserted in the first oil passage 41. A sliding region 46a in which the inertial body 45 is slidably provided is formed on the other end side of the first oil passage 41. The inertial body 45 has a shape that is in close contact with the inner wall of the sliding region 46a in the first oil passage 41. The sliding region 46a is formed so that the inner diameter is larger than that of the non-sliding region 46b where the inertial body 45 does not slide. As a result, the inertial body 45 reciprocates only within the sliding region 46a. A stopper may be provided to prevent the inertial body 45 from moving from the sliding region 46a to the non-sliding region 46b. In this case, the inner diameters of the sliding region 46a and the non-sliding region 46b may be substantially the same.

Further, the first oil passage 41 has a first connection portion 47 to which the second oil passage 42 is connected between the discharge port 43 and the sliding region 46a. The first oil passage 41 has a first regulation unit 48 between the discharge port 43 and the first connection unit 47. The first regulation unit 48 allows the flow of oil from the sliding region 46a side in the first oil passage 41 to the discharge port 43 side, and allows the oil to flow from the discharge port 43 side to the sliding region 46a side in the first oil passage 41. Suppress the flow of oil to. Specifically, the first regulation unit 48 can use, for example, a check valve.

Further, in the first oil passage 41 in the piston pin 24, as the connecting rod 6 rotates, the first oil passage 41 in the piston pin 24 and the first oil passage 41 in the connecting rod 6 communicate with each other. Tapered portions 49a and 49b are formed so as not to be interrupted. The tapered portion 49a is provided on the right side of the piston pin 24 and has a shape in which the diameter increases toward the right side. Then, as shown in FIG. 2B, the tapered portion 49a has a substantially elliptical external shape. The tapered portion 49b is provided symmetrically with the tapered portion 49a in the piston pin 24. That is, the tapered portion 49b is provided on the left side of the piston pin 24, has a shape in which the diameter becomes tapered toward the left side, and has a substantially elliptical appearance shape.

Further, the second oil passage 42 is formed in the connecting rod 6. The second oil passage 42 communicates the first suction port 26 with the first oil passage 41. The first suction port 26 is located at one end of the second oil passage 42, and the first connection portion 47 is located at the other end of the second oil passage 42.

Further, the second oil passage 42 has a second regulation unit 50. However, the second regulation unit 50 may be provided anywhere in the second oil passage 42 as long as it is between the first suction port 26 and the first connection unit 47. Here, the second regulation unit 50 is provided in the second oil passage 42 substantially between the first suction port 26 and the first connection unit 47. For example, the second regulation unit 50 may be provided so as to be adjacent to the first suction port 26, or the second regulation unit 50 may be provided so as to be adjacent to the first connection unit 47.

The second regulation unit 50 allows the flow of oil from the first suction port 26 side in the second oil passage 42 to the first connection portion 47 side, and allows the oil to flow from the first connection portion 47 side in the second oil passage 42. The flow of oil to the first suction port 26 side is suppressed. Specifically, the second regulation unit 50 can use, for example, a check valve.

When the piston 20 reciprocates, an inertial force acts on the inertial body 45. Specifically, when the piston 20 moves toward the top dead center, that is, to the left, an inertial force acts on the inertial body 45 to the right, and the inertial body 45 is relative to the right in the sliding region 46a. Sliding on. When the inertial body 45 moves to the right in the sliding region 46a, the pressure in the first oil passage 41 between the inertial body 45 and the first regulating portion 48 and in the second oil passage 42 is reduced. As a result, the oil stored in the recess 25 is sucked from the first suction port 26 into the second oil passage 42 and the first oil passage 41.

Further, when the piston 20 moves toward the top dead center, that is, to the left as described above, an inertial force acts to the right on the oil stored in the recess 25, and the oil is biased to the right side of the recess 25. It is stored. Therefore, as described above, by providing the first suction port 26 at the right end of the recessed portion 25, the oil collected on the right side of the recessed portion 25 can be efficiently sucked from the first suction port 26.

On the other hand, when the piston 20 moves toward the bottom dead point, that is, to the right, an inertial force acts on the inertial body 45 to the left, and the inertial body 45 slides relatively to the left in the sliding region 46a. Move. When the inertial body 45 moves to the left in the sliding region 46a, it is formed in the first oil passage between the inertial body 45 and the first regulating portion 48, and between the first connecting portion 47 and the second regulating portion 50. The inside of the second oil passage 42 between them is pressurized. As a result, the oil in the first oil passage 41 is discharged from the discharge port 43 toward the back surface of the crown surface 20a of the piston 20. Then, the piston 20 can be cooled by the oil supplied to the back surface of the crown surface 20a.

When the inertial body 45 moves to the right in the sliding region 46a, the air in the sliding region 46a is exhausted from the air hole 44. Further, when the inertial body 45 moves to the left in the sliding region 46a, the air in the sliding region 46a is taken in from the air hole 44. Further, the inner wall surface of the first oil passage 41 in the sliding region 46a is lubricated with oil. As a result, the inertial body 45 can move smoothly in the sliding region 46a.

With the cooling mechanism 40 in the first embodiment as described above, it is possible to vigorously discharge the oil from the discharge port 43 by using the explosive pressure in the combustion chamber 7. This makes it possible to efficiently cool the piston 20.

(Second Embodiment)
Next, the cooling mechanism 140 in the second embodiment will be described. FIG. 3 is a schematic view for explaining the cooling mechanism 140 in the second embodiment. The white arrows in FIG. 3 indicate the direction in which the oil flows. Further, the components substantially the same as the components described in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The cooling mechanism 140 in the second embodiment is mainly different from the cooling mechanism 40 in the first embodiment described above in the configurations of the piston pin 124 and the first oil passage 141. That is, as shown in FIG. 3, the non-sliding region 146b of the first oil passage 141 of the cooling mechanism 140 is formed along the periphery of the piston pin hole 23 on the left end side of the connecting rod 106. In this way, the first oil passage 141 is formed only in the connecting rod 106. Therefore, it is not necessary to form the first oil passage 141 in the piston pin 124.

Further, the first oil passage 141 has a first regulation unit 148 between the discharge port 43 and the first connection unit 47. The first regulation unit 148 allows the flow of oil from the sliding region 46a side in the first oil passage 141 to the discharge port 43 side, and allows the oil to flow from the discharge port 143 side to the sliding region 46a side in the first oil passage 141. Suppress the flow of oil to. Specifically, the first regulation unit 148 can use, for example, a check valve.

In the case of the cooling mechanism 140 as described above, since the piston pin 124 may be used without an oil passage formed inside, the piston 20 can be efficiently cooled simply by replacing the connecting rod 106 with a conventional product. It becomes possible to do.

(Third Embodiment)
Next, the cooling mechanism 240 in the third embodiment will be described. FIG. 4 is a schematic view for explaining the cooling mechanism 240 according to the third embodiment. The white arrows in FIG. 4 indicate the direction in which the oil flows. Further, the components substantially the same as the components described in the first embodiment and the second embodiment are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 4A shows a schematic cross-sectional view of the cooling mechanism 240, and FIG. 4B shows an enlarged view of the vicinity of the sliding region 246a. As shown in FIG. 4A, the cooling mechanism 240 includes a first oil passage 241, a second oil passage 242, a third oil passage 251 and a fourth oil passage 261. Further, in order to be provided on the outer peripheral surface of the connecting rod 6, a recessed portion 225 for storing oil is provided. The recessed portion 225 is formed so that a part of the connecting rod 206 on the upper surface side is cut out. Further, the recessed portion 225 is provided with a first suction port 226a and a second suction port 226b that open on the outer peripheral surface of the connecting rod 206. The positions where the first suction port 226a and the second suction port 226b are provided are not particularly limited as long as they are inside the recessed portion 225, but the first suction port 226a is provided at the right end of the recessed portion 225 and at the left end of the recessed portion 225. It is preferable to provide the second suction port 226b.

The first oil passage 241 is formed only in the connecting rod 206, as in the second embodiment. A discharge port 43 for discharging oil is formed at one end of the first oil passage 241 and a second connection portion 252 is formed at the other end side of the first oil passage 241. The discharge port 43 opens at the tip on the left side of the connecting rod 206 so as to face the back surface of the crown surface 20a of the piston 20. Further, the first oil passage 241 has a first connection portion 247 to which the second oil passage 242 is connected between the discharge port 43 and the second connection portion 252. In the first oil passage 241, a sliding region 246a is formed between the first connecting portion 247 and the second oil passage 242. The sliding region 246a is formed so that the inner diameter is larger than that of the non-sliding region 246b where the inertial body 45 does not slide.

The first oil passage 241 has a first regulation unit 248 between the discharge port 43 and the first connection unit 247. The first regulation unit 248 allows the flow of oil from the sliding region 246a side in the first oil passage 241 to the discharge port 43 side, and allows the oil to flow from the discharge port 43 side to the sliding region 246a side in the first oil passage 241. Suppress the flow of oil to. Specifically, the first regulation unit 248 can use, for example, a check valve.

Further, the second oil passage 242 is formed in the connecting rod 206. The second oil passage 242 communicates the first suction port 226a and the first oil passage 241. The first suction port 226a is located at one end of the second oil passage 242, and the first connection portion 247 is located at the other end of the second oil passage 242. Further, the second oil passage 242 has a second regulating portion 250 between the first suction port 226a and the first connecting portion 247.

Further, the third oil passage 251 is formed in the connecting rod 206. The third oil passage 251 communicates the second suction port 226b and the first oil passage 241. The second suction port 226b is located at one end of the third oil passage 251 and the second connecting portion 252 is located at the other end of the third oil passage 251. Further, the third oil passage 251 has a third regulating portion 253 between the second suction port 226b and the second connecting portion 252.

Further, the fourth oil passage 261 is formed in the connecting rod 206. The fourth oil passage 261 communicates the second oil passage 242 and the third oil passage 251. Further, one end of the fourth oil passage 261 is located between the second regulation portion 250 and the first connection portion 247, and the other end of the fourth oil passage 261 is the third regulation portion 253 and the second connection portion 252. Located between. Further, the fourth oil passage 261 has a fourth regulation portion 262 between the connection portion between the fourth oil passage 261 and the second oil passage 242 and the connection portion between the fourth oil passage 261 and the third oil passage 251. Have.

FIG. 5 is a schematic view for explaining the cooling mechanism 240 according to the third embodiment, and is a schematic cross-sectional view when the cooling mechanism 240 of FIG. 4B is viewed from the left side. The white arrows in FIG. 5 indicate the direction in which the oil flows. As shown in FIG. 5, the second regulating unit 250 allows the flow of oil from the first suction port 226a side to the first connecting portion 247 side in the second oil passage 242, and allows the oil to flow in the second oil passage 242. The flow of oil from the first connection portion 247 side to the first suction port 226a side is suppressed. Specifically, the second regulation unit 250 can use, for example, a check valve.

Further, the third regulation unit 253 allows the flow of oil from the second suction port 226b side in the third oil passage 251 to the second connection portion 252 side, and allows the oil to flow in the third oil passage 251 to the second connection portion 252. The flow of oil from the side to the second suction port 226b side is suppressed. Specifically, the third regulation unit 253 can use, for example, a check valve.

Further, the fourth regulation unit 262 allows the flow of oil from the third oil passage 251 side to the second oil passage 242 side in the fourth oil passage 261 and allows the oil to flow in the fourth oil passage 261 to the third oil passage 251. The flow of oil from the side to the second oil passage 242 side is suppressed. Specifically, the fourth regulation unit 262 can use, for example, a check valve.

When the piston 20 reciprocates, an inertial force acts on the inertial body 45. Specifically, when the piston 20 moves toward the top dead center, that is, to the left, an inertial force acts on the inertial body 45 to the right, and the inertial body 45 moves relative to the right in the sliding region 246a. Sliding on. When the inertial body 245 moves to the right in the sliding region 246a, it is inside the first oil passage 241 and the second oil passage 242 between the inertial body 45 and the first regulating portion 248, and in the fourth regulating portion 262. The fourth oil passage 261 between the and the second oil passage 242 is depressurized. As a result, the oil stored in the recessed portion 225 is sucked from the first suction port 226a into the second oil passage 242 and the first oil passage 241. At the same time, in the first oil passage 241 and the third oil passage 251 between the inertial body 45 and the third regulating portion 253, and in the fourth oil passage 261 between the fourth regulating portion 262 and the third oil passage 251. Is pressurized. As a result, in the first oil passage 241 and the third oil passage 251 between the inertial body 45 and the third regulation portion 253, and in the fourth oil passage 261 between the fourth regulation portion 262 and the third oil passage 251. The oil stored in the oil is pushed out from the fourth regulation unit 262 into the second oil passage 242 and the first oil passage 241.

Further, when the piston 20 moves toward the top dead center, that is, to the left as described above, an inertial force acts to the right on the oil stored in the recess 225, and the oil is biased to the right side of the recess 225. It is stored. Therefore, as described above, by providing the first suction port 226a at the right end of the recessed portion 225, the oil collected on the right side of the recessed portion 225 can be efficiently sucked from the first suction port 226a.

On the other hand, when the piston 220 moves toward the bottom dead point, that is, to the right, an inertial force acts on the inertial body 245 to the left, and the inertial body 245 slides relatively to the left in the sliding region 246a. To do. When the inertial body 245 moves to the left in the sliding region 246a, the first oil passage 241 and the third oil passage 251 between the inertial body 45 and the third regulation portion 253, the fourth regulation portion 262 and the third The inside of the fourth oil passage 261 between the oil passage 251 and the oil passage 251 is depressurized. As a result, the oil stored in the recessed portion 225 is sucked from the second suction port 226b into the third oil passage 251 and the first oil passage 241. At the same time, in the first oil passage 241 between the inertial body 245 and the first regulating portion 248, in the second oil passage 242 between the first connecting portion 247 and the second regulating portion 250, and the fourth. The fourth oil passage 261 between the regulation unit 262 and the second oil passage 242 is pressurized. As a result, the oil in the first oil passage 241 is discharged from the discharge port 43 toward the back surface of the crown surface 20a of the piston 20. Then, the piston 20 can be cooled by the oil supplied to the back surface of the crown surface 20a.

Further, when the piston 20 moves toward the bottom dead center, that is, to the right as described above, an inertial force acts to the left on the oil stored in the recess 225, and the oil is biased to the left side of the recess 225. It is stored. Therefore, as described above, by providing the second suction port 226b at the left end of the recessed portion 225, the oil collected on the left side of the recessed portion 225 can be efficiently sucked from the second suction port 226b.

With the cooling mechanism 240 according to the third embodiment as described above, the oil stored in the recessed portion 225 can be efficiently supplied to the piston 20 by the reciprocating motion of the piston 20 by a simple configuration. ..

In the third embodiment, the case where the first oil passage 241 is not formed in the piston pin 124 is shown, but the first oil passage 241 is formed in the piston pin 124 in the same manner as in the first embodiment. You may.

Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. Will be done.

Further, in the above-described embodiment, the case where the engine 1 is a horizontally opposed engine has been described. However, the engine 1 is not limited to the horizontally opposed engine. For example, it can be applied to a V-type engine.

Further, in the first embodiment described above, the relative positions of the piston pin 24 and the piston 20 are fixed, and the relative positions of the piston pin 24 and the connecting rod 6 are not fixed. Not limited to this. That is, the relative positions of the piston pin 24 and the piston 20 are not fixed, and the relative positions of the piston pin 24 and the connecting rod 6 may be fixed.

The present invention can be used for internal combustion engines.

6, 106, 206 Connecting rods 25, 225 Recesses 26, 226a First suction port 226b Second suction port 40, 140, 240 Cooling mechanism 41, 141, 241 First oil passage 42, 242 Second oil passage 43, 143 Discharge port 45, 245 Inertial bodies 46a, 146a, 246a Sliding area 46b, 146b, 246b Non-sliding area 47, 147, 247 First connection 48, 148, 248 First regulation 50, 250 Second regulation 251 3rd oil passage 252 2nd connection part 253 3rd regulation part 261 4th oil passage 262 4th regulation part

Claims (3)

A first oil passage, which is formed at least in a connecting rod, has a discharge port for discharging oil at one end, and has a sliding region in which an inertial body is slidable.
A first suction port provided in a recess formed on the outer peripheral surface of the connecting rod, a second oil passage connecting the first oil passage, and a second oil passage.
With
In the first oil passage, a first connection portion to which the second oil passage is connected is formed between the sliding region and the discharge port.
The first oil passage allows oil to flow from the sliding region side to the discharge port side between the discharge port and the first connection portion, and allows the oil to flow from the discharge port side to the sliding region side. Has a first regulatory section that restricts the flow of oil to
The second oil passage allows the flow of oil from the first suction port side to the first connection portion side, and suppresses the flow of oil from the first connection portion side to the first suction port side. A cooling mechanism having a second regulatory unit. A third oil passage that communicates the second suction port provided in the recess and the first oil passage.
A fourth oil passage connecting the second oil passage and the third oil passage,
With
The first oil passage is formed with a second connecting portion to which the third oil passage is connected.
The sliding region is located between the first connection portion and the second connection portion.
The third oil passage allows the flow of oil from the second suction port side to the second connection portion side, and suppresses the flow of oil from the second connection portion side to the second suction port side. Has a third regulatory department
The fourth oil passage allows the flow of oil from the third oil passage side to the second oil passage side, and suppresses the flow of oil from the second oil passage side to the third oil passage side. The cooling mechanism according to claim 1. The first suction port is provided at a position closer to the second connection portion than the second suction port.
The cooling mechanism according to claim 2, wherein the second suction port is provided at a position closer to the first connection portion than the first suction port.

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