JP2007064003A - Lubricating oil feeding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricating oil feeding device for an internal combustion engine capable of sufficiently feeding lubricating oil to a friction surface of bearing part, such as a sliding part, while reducing driving load of an oil pump. <P>SOLUTION: A lubricating oil feeding device for feeding lubricating oil to a component element of an object to be lubricated in an internal combustion engine, is equipped with an oil sump 30 for storing lubricating oil, a negative pressure generating means 38 for generating negative pressure and sucking/feeding means 35, 36, 37 for sucking lubricating oil stored in the oil sump by the negative pressure generated by the negative pressure generating means and feeding the lubricating oil to the component element of an object to be lubricated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lubricating oil supply apparatus.

  Generally, in an internal combustion engine, lubricating oil is supplied to each bearing part and sliding part in the internal combustion engine. As a result, fluid lubrication is ensured on the friction surfaces such as the bearing portion and the sliding portion, and friction and wear on these friction surfaces are reduced, and cooling on the friction surfaces is promoted.

  In this way, when supplying lubricating oil to each bearing part and sliding part in the internal combustion engine, the lubricating oil stored in an oil reservoir such as an oil pan is pumped up by the oil pump and the pumped lubricating oil is pumped into the internal combustion engine. The bearings and sliding parts are fed by pressure.

  In the lubricating device described in Patent Document 1, the lubricating oil stored in the oil pan is pumped up by an oil pump, and the pumped-up lubricating oil is supplied to each of the internal combustion engines via the crankshaft system lubrication path and the valve system lubrication path. Lubricating oil is supplied to the bearing part and the sliding part. In particular, this lubrication apparatus has a supply ratio adjusting valve that adjusts the ratio between the flow rate of the lubricating oil flowing into the crankshaft system lubrication path and the flow rate of the lubricating oil flowing into the valve system lubrication path. When the amount of lubricating oil stored in the engine becomes small, the supply rate adjustment valve is controlled to reduce the flow rate of the lubricating oil flowing into the crankshaft lubricating oil path. The supply ratio of the lubricating oil to the crankshaft component that consumes a large amount of lubricating oil is assumed to be small, and the amount of lubricating oil consumption can be suppressed to a small amount.

JP-A-5-149120

  By the way, many of the oil pumps used in the internal combustion engine are driven by a crankshaft of the internal combustion engine via a belt or the like. As described above, since a part of the output of the internal combustion engine is used for driving the oil pump, when the drive load of the oil pump for pumping up the lubricating oil becomes large, the drive loss with respect to the output of the internal combustion engine becomes large. . For this reason, from the viewpoint of reducing the driving loss with respect to the output of the internal combustion engine, it is necessary that the capacity of the oil pump is small and the driving load of the oil pump is small.

  On the other hand, if the capacity of the oil pump is reduced and the driving load of the oil pump is reduced, the flow rate of the lubricating oil pumped up by the oil pump decreases, and sufficient lubricating oil is supplied to the friction surfaces such as the bearings and sliding parts. And the friction and wear on the friction surface increases due to the oil film running out.

  SUMMARY OF THE INVENTION The present invention provides a lubricating oil supply device for an internal combustion engine that can sufficiently supply lubricating oil to a friction surface such as a bearing portion or a sliding portion while reducing a driving load of an oil pump.

In order to solve the above-described problem, in the first invention, in a lubricating oil supply device that supplies lubricating oil to components to be lubricated in an internal combustion engine, an oil reservoir for storing the lubricating oil, and a negative pressure that generates a negative pressure Generating means, and suction supply means for sucking up the lubricating oil stored in the oil reservoir by the negative pressure generated by the negative pressure generating means and supplying it to the components to be lubricated.
According to the first aspect, since the lubricating oil is sucked up by the negative pressure generated by the negative pressure generating means without using the oil pump, the driving load of the oil pump is reduced. Further, the lubricating oil is supplied to the components to be lubricated of the internal combustion engine using negative pressure instead of the oil pump.

In the second invention, in the first invention, the crank chamber lubrication path for lubricating the components to be lubricated in the crank chamber and the crank chamber lubrication path are separate paths and lubricate the valve train. It comprises two lubrication paths including a valve train lubrication path for lubricating the target component, and the suction supply means is connected to the valve target lubrication target component via the valve train lubrication path. Used only to supply lubricating oil.
According to the second aspect of the invention, the lubricating oil is supplied to the component to be lubricated of the valve operating system by the suction supply means. The suction supply means sucks up and supplies the lubricating oil by negative pressure, and the flow rate of the lubricating oil sucked up and supplied by the negative pressure is usually smaller than the flow rate of the lubricating oil pumped up and supplied by the oil pump. However, since the components to be lubricated in the valve system are not so severe in lubrication conditions, the components to be lubricated in the valve system can be sufficiently lubricated by sucking up and supplying the lubricating oil by the suction and supply means.

  In a third invention, in the first or second invention, the suction supply means includes a negative pressure control valve for controlling the magnitude of the negative pressure generated by the negative pressure generating means, and the negative pressure control By controlling the magnitude of the negative pressure by the valve, the amount of lubricating oil supplied from the suction supply means to the component to be lubricated is controlled.

  According to a fourth invention, in any one of the first to third inventions, a main passage communicating with the negative pressure generating means and the oil reservoir, and a branch from the main passage toward a component to be lubricated And when the negative pressure generated by the negative pressure generating means is provided to the main passage, the negative pressure causes the lubricating oil to be sucked up vertically above the branching portion to the branch passage. At the same time, when the supply of the negative pressure generated by the negative pressure generating means to the main passage is stopped, at least a part of the lubricating oil sucked up vertically above the branch portion passes through the branch passage. To be supplied to each component to be lubricated.

  According to a fifth invention, in the fourth invention, a lubricating oil passage prevention member for preventing the passage of the lubricating oil is provided on the main passage and closer to the negative pressure generating means than the branching portion to the branch passage. .

  According to a sixth aspect, in the fifth aspect, the lubricating oil passage preventing member includes a space separation plate movable in the axial direction of the main passage, and the space separation plate is separated from the main passage by the negative pressure generating means. Move according to the negative pressure provided.

  ADVANTAGE OF THE INVENTION According to this invention, lubricating oil can fully be supplied to friction surfaces, such as a bearing part and a sliding part, which are the lubrication target components of an internal combustion engine, reducing the drive load of an oil pump.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side sectional view of an internal combustion engine provided with the lubricating oil supply device of the present invention, and FIG. 2 is an enlarged side sectional view of a portion A in FIG.

  Referring to FIG. 1, 1 is a cylinder block fixed on an oil pan (oil reservoir) 2, 3 is a cylinder head fixed on the cylinder block 1, 4 is a cylinder head cover fixed on the cylinder head 3, 5 Is a crank chamber defined by the cylinder block 1 and the oil pan 2, and 6 is a cylinder head chamber defined by the cylinder head 3 and the cylinder head cover 4. The crankshaft 7 is connected to each piston 10 via a connecting rod 8 and a piston pin 9. A combustion chamber 11 is formed between the top surface of the piston 10 and the lower wall surface of the cylinder head 3. On the other hand, the valve mechanism 12 is accommodated in the cylinder head chamber 6. The valve train mechanism 12 includes an intake valve 13 and an exhaust valve 14, and an intake camshaft 15 and an exhaust camshaft 16. Further, an intake port 17 opened and closed by an intake valve 13 and an exhaust port 18 opened and closed by an exhaust valve 14 are provided in the cylinder head 3.

  Referring to FIG. 2, which is an enlarged view of part A in FIG. 1, a valve guide insertion hole 21 is formed in the cylinder head 1, and the valve stem 13 a of the intake valve 13 is guided into the valve guide insertion hole 21. The valve guide 22 is press-fitted. A seal member 23 for sealing an annular gap formed between the valve guide and the valve stem 13a is attached to the top of the valve guide 22. The seal member 23 may be attached to the cylinder head 3. A valve retainer 24 is attached to the top of the valve stem 13a via a cotter. A compression spring 25 is inserted between the valve retainer 24 and the cylinder head 3, and the urging force of the compression spring 25 urges the intake valve 13 in the valve closing direction. Further, a valve lifter 26 is inserted between the top of the valve stem 13a and the intake cam 15a for driving the intake valve 13. The valve lifter 26 is guided by a valve lifter guide hole 27 formed in the cylinder head 3.

  When the intake cam 15a acts on the valve lifter 27, the valve lifter 26 is lowered together with the intake valve 13, and thus the intake valve 13 is opened. On the other hand, when the intake cam 15a does not act on the valve lifter 26, the urging force of the compression spring 25 acting on the valve retainer 24 raises the valve lifter 26 and the intake valve 13, and thus the intake valve 13 is closed. Since the exhaust valve 14 is the same, the description thereof is omitted.

  Still referring to FIG. 2, a recess 30 is formed at the lowest position in the cylinder head chamber 6. The recess 30 constitutes a sub oil pan (oil reservoir), that is, an oil pan in which valve system lubricating oil is stored, and is hereinafter referred to as a sub oil pan. As will be described later, the lubricating oil that has lubricated the intake cam 15 a, the valve lifter 26, and the like flows along the wall surface of the cylinder head chamber 6 and is collected in the sub oil pan 30.

  The internal combustion engine shown in FIG. 1 has two lubrication paths. That is, the internal combustion engine includes a lubrication path for the crank chamber for lubricating the components to be lubricated in the crank chamber 5, such as the crankshaft 7, the connecting rod 8, the piston 10, and the valve train mechanism 12 in the cylinder head chamber 6. And a valve operating lubrication path for lubricating the valve.

  FIG. 3 shows a lubrication path for the crank chamber. In this drawing, the solid line indicates the lubricating oil flow in which the lubricating oil is forcibly sent by the oil pump, while the broken line indicates the lubricating oil flow in which the lubricating oil flows due to natural fall.

  Referring to FIG. 3, in the crank chamber lubricating path, the lubricating oil in the oil pan 2 is pumped up by an engine-driven oil pump through an oil strainer. The lubricating oil discharged from the oil pump is then supplied to the crankshaft 7 through the oil filter. Part of the lubricating oil supplied to the crankshaft 7 returns to the oil pan 2, and the remaining lubricating oil is then supplied to the connecting rod 8. Part of the lubricating oil supplied to the connecting rod 8 returns to the oil pan 2, and the remaining lubricating oil is then supplied to the piston 10 and the cylinder wall. The lubricating oil supplied to the piston 10 and the cylinder wall returns to the oil pan 2. Note that a relief valve is provided between the oil pump and the oil filter, for example, to release the lubricating oil discharged from the oil pump to the oil pan when the downstream of the oil pump is clogged.

  On the other hand, for the valve train lubrication path, an engine-driven oil pump (hereinafter referred to as “sub oil pump”) is usually used in the same manner as the crank chamber lubrication path described above. The lubricating oil in the oil pan is pumped up, and the lubricating oil is supplied to each component of the valve train mechanism 12. Specifically, the lubricating oil in the sub oil pan is pumped up by the sub oil pump, and the lubricating oil discharged from the sub oil pump is supplied to the journal bearing of the camshaft. The lubricating oil supplied to the journal bearing of the camshaft is then supplied to the cam, valve lifter and valve stem and then returned to the sub oil pan.

  The crank chamber lubrication path is basically arranged in the crank chamber 5, while the valve train lubrication path is basically arranged in the cylinder head chamber 6. For this reason, the lubricating oil used in the crankcase lubricating path and the lubricating oil used in the valve train lubricating path are basically not mixed, and different lubricating oils should be used in these two lubricating paths. Can do. In particular, it is preferable to use a high-viscosity lubricating oil in the valve train lubrication path, and it is preferable to use a low-viscosity lubricating oil in the crankcase lubrication path. By using different lubricating oils in the respective lubrication paths in this way, it is possible to reduce friction in the valve train mechanism and the crank chamber mechanism (crankshaft and piston) that are generated when the internal combustion engine is operated.

  Moreover, deterioration of the lubricating oil in the valve operating system lubricating oil path can be reduced by providing different lubricating paths. That is, the lubricating oil in the lubricating path for the crank chamber comes into contact with the blow-by gas that leaks from the combustion chamber 11 into the crank chamber 5, whereby carbon tends to be mixed into the lubricating oil. This carbon-containing lubricating oil is not suitable for lubrication of a valve train mechanism that is boundary lubrication. For this reason, if the lubricating oil in the valve train lubrication path and the lubricating oil in the crank chamber lubrication path are common or mixed with each other, the lubricating oil in the valve train lubrication path deteriorates early. It will be. On the other hand, the lubrication oil used in the crankcase lubrication path and the lubrication oil used in the valve train lubrication path do not basically mix with each other by using a different lubrication path. It is possible to reduce the deterioration of the lubricating oil in the valve system lubrication path.

  By the way, if the sub oil pump is used to pump up the lubricating oil in the sub oil pan as described above for the valve train lubrication path, a part of the output of the internal combustion engine is used to drive the sub oil pump. The drive loss with respect to the output of the internal combustion engine becomes large. In addition, if a sub oil pump is provided, the manufacturing cost increases.

  Therefore, in this embodiment, the lubricating oil is supplied in the valve train lubrication path without using the sub oil pump. Hereinafter, with reference to FIGS. 4 to 6, the supply of the lubricating oil in the valve train lubrication path in the present embodiment will be described in detail.

  FIG. 4 is a top view schematically showing the cylinder head 3, and only the vicinity of the intake camshaft 15 is shown. FIG. 4 shows a state where the cylinder head cover 4 fixed on the cylinder head 3 is removed. As can be seen from the figure, the cylinder head 3 is provided with an intake camshaft 15 having a plurality of intake cams 15a. FIG. 4 shows an intake camshaft 15 for a four-cylinder internal combustion engine. In the internal combustion engine of this embodiment, two intake valves 13 are provided for each cylinder, and each intake valve 13 is driven to open and close by one intake cam 15a. The intake camshaft 15 is connected to the crankshaft 7 via a timing chain or the like, and is rotated in synchronization with the rotation of the crankshaft 7. In particular, in the present embodiment, a continuously variable valve timing mechanism (not shown) that can change the phase angle of the intake valve 13 by continuously changing the rotation angle of the camshaft 15 relative to the rotation angle of the crankshaft 7. Have

  A cam cap 31 for rotatably locking the intake camshaft 15 on the cylinder head 3 is disposed on the cylinder head 3. The cam cap 31 is disposed so as to lock the intake camshaft 15 on the cylinder head 3 between the two intake cams 15a corresponding to one cylinder. Each of the cam caps 31 is fixed to the cylinder head 3 by two bolts 32, and the upper surface portion of the cylinder head 3 facing the cam cap 31 and the bottom surface of the cam cap 31 are connected to the journal bearing 33 of the intake camshaft 15 (FIG. 5). (See below). The intake camshaft 15 is received by these journal bearings 33 and can rotate within the journal bearings 33.

  Here, the valve train lubrication path of the present embodiment includes a cam supply mechanism 35 for supplying lubricant to the intake cam 15a and the valve lifter 26, and a bearing supply mechanism 36 for supplying lubricant to the journal bearing 33. And have.

  FIG. 5 is a diagram schematically showing the cam supply mechanism 35 in the cross section of the cylinder head 3 taken along the line V-V in FIG. 4. The cam supply mechanism 35 includes a main pipe 40 that defines a main passage and a branch pipe 41 that defines a branch passage. The main pipe 40 is disposed so as not to extend in the horizontal direction, and is disposed so as to extend in the vertical direction in the present embodiment. The main pipe 40 communicates with the sub oil pan 30 at one end, and communicates with a vacuum switching valve (hereinafter referred to as “VSV”) 37 through the collecting pipe 42 at the other end. The branch pipe 41 branches from the main pipe 40, and its tip is directed to at least one of the intake cams 15a, the valve lifter 26, and the contact portion between the intake cam 15a and the valve lifter 26. In particular, the branch pipe 41 is disposed so as to extend downward from the main pipe 40 in the horizontal direction.

  At the end of the main pipe 40 on the sub oil pan 30 side (or at least in the main pipe 40 on the sub oil pan 30 side of the branch portion 41a of the branch pipe 41 from the main pipe 40), a check valve for main pipe is provided. 43 is provided. The main pipe check valve 43 allows the lubricating oil to flow from the end on the sub oil pan 30 side toward the end on the VSV 37 side, but from the end on the VSV 37 side to the end on the sub oil pan 30 side. Prohibit lubricating oil from flowing toward you. The branch pipe 41 is provided with a branch pipe check valve 44. The branch pipe check valve 44 permits the lubricating oil to flow from the branch portion 41a toward the intake cam 15a and the like, but prohibits the lubricant oil from flowing from the intake cam 15a side toward the branch portion 41a.

  A cam supply mechanism 35 including a main pipe 40 and a branch pipe 41 is provided for each intake cam 15a. As shown in FIG. 4, the main pipe 40 of the cam supply mechanism 35 corresponding to all the intake cams 15 a is communicated with one VSV 37 by the collective pipe 42. That is, the collective pipe 42 communicates with the main pipes 40 of all the cam supply mechanisms 35, and the multiple main pipes 40 are aggregated into one pipe and communicated with the VSV 37.

  In addition to the collecting pipe 42, the VSV 37 communicates with a negative pressure pipe 45 that communicates with the negative pressure generator 38 and an atmospheric pressure pipe 46 that communicates with the atmosphere. The negative pressure generator 38 is a device conventionally provided in an internal combustion engine in order to provide a negative pressure to, for example, a brake booster (not shown), a negative pressure actuator that operates using the negative pressure, or the like. As the negative pressure generator 38, for example, when a spark ignition type internal combustion engine (gasoline engine) is used as the internal combustion engine, an intake pipe on the downstream side of the throttle valve is used. When it is small, a large negative pressure is generated. On the other hand, when a compression self-ignition internal combustion engine (diesel engine) is used as the internal combustion engine, a vacuum pump that generates negative pressure using the output of the internal combustion engine is used.

  The VSV 37 converts the pressure provided to the collecting pipe 42, that is, the pressure provided to the end of the main pipe 40 on the VSV 37 side, into the negative pressure generated by the negative pressure generating device (negative pressure generating means) 38 and the atmospheric pressure. Can be switched between. That is, when the VSV 37 is on, the pressure at the end of the main pipe 40 on the VSV 37 side is negative, while when the VSV 37 is off, the pressure at the end of the main pipe 40 on the VSV 37 side is large. Atmospheric pressure.

  The cam supply mechanism 35 configured as described above supplies lubricating oil to the intake cam 15a and the valve lifter 26 as follows. First, as shown in FIG. 5A, when the VSV 37 is turned on, the pressure at the end of the main pipe 40 on the VSV 37 side is set to a negative pressure. At this time, since the lubricating oil tends to flow from the end on the sub oil pan 30 side toward the end on the VSV 37 side in the main pipe 40 due to the negative pressure, the check valve for the main pipe is used. 43 is opened. On the other hand, in the branch pipe 41, the lubricating oil tends to flow from the intake cam 15a side toward the branch portion 41a due to the negative pressure, so that the branch pipe check valve 44 is closed. Accordingly, when the VSV 37 is turned on, the lubricating oil in the branch pipe 41 basically does not move, while in the main pipe 40, the lubricating oil is sucked up vertically from the sub oil pan 30 by negative pressure. In the present embodiment, the VSV 37 is turned on until at least the liquid level of the lubricating oil in the main pipe 40 is sucked vertically upward from the branch portion 41a to the branch pipe 41.

  Thereafter, as shown in FIG. 5B, when the VSV 37 is turned off, the pressure at the end of the main pipe 40 on the VSV 37 side is set to atmospheric pressure. At this time, in the main pipe 40, the lubricating oil tends to flow from the end on the VSV 37 side toward the end on the sub oil pan 30 side due to gravity, so the main pipe check valve 43 is closed. On the other hand, in the branch pipe 41, the lubricating oil tends to flow from the branch portion 41a toward the intake cam 15a due to gravity, so that the branch pipe check valve 44 is opened. Therefore, even if the VSV 37 is turned off, the lubricating oil in the main pipe 40 is not returned into the sub oil pan 30 via the main pipe check valve 43. On the other hand, in the branch pipe 41, lubricating oil is supplied to the intake cam 15a and the valve lifter 26 from the end on the intake cam 15a side. In particular, in this embodiment, when the VSV 37 is turned on, the lubricating oil sucked up vertically above the branching portion in the main pipe 40 is basically all intake cams when the VSV 37 is turned off. 15a and the valve lifter 26.

  As described above, according to the present embodiment, the cam supply mechanism 35 and the VSV 37 suck up the lubricating oil stored in the sub oil pan 30 by the negative pressure generated by the negative pressure generating means, that is, the components to be lubricated, that is, A suction supply means for supplying the intake cam 15a, the valve lifter 26, and the like is configured. Further, the amount of lubricating oil supplied to the intake cam 15a and the like can be controlled by changing the switching cycle of the VSV 37. That is, when the VSV 37 switching period is early, the amount of lubricant supplied is increased, and conversely, when the VSV 37 switching period is delayed, the amount of lubricant supplied is decreased.

  FIG. 6 is a view schematically showing the bearing supply mechanism 36 in the cross section of the cylinder head 3 along the line VI-VI in FIG. 4. The bearing supply mechanism 36 includes a block inner hole 47 formed in the portion of the cylinder block 3 facing the cam cap 31 and extending in the vertical direction, and a cap inner hole 48 formed in the cam cap 31 extending in the vertical direction. . The block inner hole 47 and the cap inner hole 48 are formed so as to be aligned when the cam cap 31 is fixed on the cylinder block 3. A lower pipe 49 communicating with the sub oil pan 30 is provided below the block inner hole 47, and an upper pipe 50 is provided above the cap inner hole 48. The upper pipe 50 communicates with the cap inner hole 48 at one end and communicates with the VSV 37 through the collecting pipe 51 at the other end. The lower pipe 49, the block inner hole 47, the cap inner hole 48, and the upper pipe 50 define a main passage that communicates with the VSV 37 at one end and communicates with the sub oil pan 30 at the other end.

  The bearing supply mechanism 36 further has a branch hole 52 that defines a branch passage that branches from the main passage in the cylinder block 3 and the cam cap 31. The tip of the branch hole 52 communicates with the journal bearing 33. That is, the tip of the branch hole 52 communicates with at least one of the upper surface portion of the cylinder head 3 facing the cam cap 31 and the bottom surface of the cam cap 31.

  A bearing supply mechanism 36 including a main passage (lower pipe 49, block inner hole 47, cap inner hole 48 and upper pipe 50) and a branch hole 52 is provided for each cam cap 31. As shown in FIG. 4, the main passage of the bearing supply mechanism 36 corresponding to all the cam caps 31 is communicated with one VSV 37 by the collecting pipe 51. That is, the collective pipe 51 communicates with the main passages of all the bearing supply mechanisms 36, and the plurality of main passages are gathered into one pipe and communicated with the VSV 37.

  In the present embodiment, as shown in FIG. 4, the same VSV 37 as that connected to the cam supply mechanism 35 is connected to the bearing supply mechanism 36. Therefore, the VSV 37 switches the pressure provided to the collecting pipe 51, that is, the pressure provided to the end portion of the main passage on the VSV 37 side, between the negative pressure generated by the negative pressure generator 38 and the atmospheric pressure. Can do. That is, when the VSV 37 is on, the pressure at the end of the main passage on the VSV 37 side is negative, while when the VSV 37 is off, the pressure at the end of the main passage on the VSV 37 side is atmospheric pressure. Is done.

  In the bearing supply mechanism 36 configured as described above, lubricating oil is supplied to the journal bearing 33 as follows. First, when the VSV 37 is turned on, the pressure at the end of the main passage on the VSV 37 side is set to a negative pressure. At this time, the lubricating oil is sucked up in the main passage 37 from the end portion on the sub oil pan 30 side toward the end portion on the VSV 37 side by the negative pressure. At this time, when the lubricating oil is sucked up vertically upward from the branching portion to the branch hole 52, a part of the sucked lubricating oil is supplied to the journal bearing 33 through the branch hole 52.

  Thereafter, when the VSV 37 is turned off, the pressure at the end of the main passage on the VSV side is set to atmospheric pressure. For this reason, the lubricating oil in the main passage flows vertically downward toward the sub oil pan 30 by gravity. At the same time, a part of the lubricating oil sucked up vertically from the branching portion to the branch hole 52 in the main passage is supplied to the journal bearing 33 through the branch hole 52.

  As described above, according to the present embodiment, the bearing supply mechanism 36 and the VSV 37 suck up the lubricating oil stored in the sub oil pan 30 by the negative pressure generated by the negative pressure generator 38, and the components to be lubricated, That is, a suction supply means for supplying to the journal bearing 33 or the like is configured.

  In this embodiment, the VSV used for the cam supply mechanism 35 and the VSV used for the bearing supply mechanism 36 are the same. However, the cam supply mechanism 35 and the bearing supply mechanism 36 use different VSVs. It may be. In this case, one VSV communicates with the collecting pipe 42 that communicates with the cam supply mechanism 35, and the other VSV communicates with the collecting pipe 51 that communicates with the bearing supply mechanism 36. As a result, the VSV can be switched between the cam supply mechanism 35 and the bearing supply mechanism 36 at different timings.

  Alternatively, the bearing supply mechanism 36 may not be connected to the VSV. As described above, while the pressure at the end portion on the VSV side of the main passage is a negative pressure, the lubricant is supplied to the journal bearing 33 through the branch hole 52. Therefore, even if the pressure at the end of the main passage on the VSV side is always a negative pressure, that is, lubricating oil is supplied to the journal bearing 33 without a VSV between the negative pressure generator 38 and the main passage. Is done. For this reason, the bearing supply mechanism 36 is connected to the VSV without intervening the VSV, as long as it communicates with the negative pressure generator 38 that can generate the negative pressure continuously or intermittently. It does not have to be done.

  Further, a check valve similar to the main pipe check valve may be provided in the lower pipe 49 of the bearing supply mechanism 36. As a result, when the VSV 37 is turned on and the pressure at the end of the main passage on the VSV side is made negative, the check valve is opened and the lubricating oil is sucked up vertically in the main passage, and then the VSV 37 Is turned off and the pressure at the end of the main passage on the VSV side is set to atmospheric pressure, the check valve is closed, and all the lubricating oil sucked up vertically from the branching portion passes through the branching hole 52. The journal bearing 33 is supplied.

  Thus, in the valve train lubrication path of the present embodiment, the lubricating oil is sucked up without using the oil pump for the valve train lubrication path. Therefore, compared to the case where the lubrication path for the valve train system and the lubrication path for the crank chamber are lubricated using an oil pump for each lubrication path of the valve train lubrication path and the crank chamber lubrication path, the manufacturing cost is reduced. Can be reduced.

  The oil pump is usually driven directly by a crankshaft of an internal combustion engine or indirectly through a belt or the like. Accordingly, when the driving load of the oil pump for pumping up the lubricating oil increases, the driving loss with respect to the output of the internal combustion engine increases. In this embodiment, since the oil pump for the valve operating system lubrication path is not required, the driving loss for the output of the internal combustion engine compared to the conventional lubricating oil supply device that requires the oil pump for the valve operating system lubrication path. Can be reduced.

  Furthermore, in the valve train lubrication path of the present embodiment, negative pressure is used without using an oil pump when supplying lubricant to the valve train mechanism. For this reason, when the oil pump is used, the lubricating oil is pumped by the oil pump. However, in the present embodiment using the negative pressure, the lubricating oil is fed by the negative pressure and gravity. For this reason, when supplying lubricating oil using negative pressure, it is possible that the lubricating oil will not reach the components to be lubricated sufficiently evenly compared to supplying lubricating oil using an oil pump. There is also sex.

  However, the lubrication conditions in the valve train mechanism are not so severe as compared to the lubrication conditions in the other components of the internal combustion engine, in particular, the components to be lubricated in which the lubricating oil is supplied by the crank chamber lubrication path. This is because the temperature in the cylinder head chamber 6 in which the valve mechanism 12 is accommodated is relatively low, and the amount of blow-by gas mixed into the cylinder head chamber 6 is extremely small. Therefore, even if the lubricating oil is supplied to the valve train mechanism using negative pressure without using the oil pump as in this embodiment, the valve train mechanism can be sufficiently lubricated.

  In the above description, as the supply of the lubricating oil to the valve train system 12, the supply of the lubricating oil around the intake camshaft 15, that is, the intake cam 15a and the corresponding valve lifter 26, and the journal of the intake camshaft 15 are provided. Although the supply of the lubricating oil to the bearing 33 has been described, the supply of the lubricating oil around the exhaust camshaft 15, that is, the supply of the lubricating oil to the journal bearing 33 of the exhaust cam and the corresponding valve lifter and the exhaust camshaft 16 is also described. A similar configuration may be used.

  In the above-described embodiment, the VSV that is an on / off valve is used to control the supply of the negative pressure to the vertically upper end of the main passage. However, the supply of such a negative pressure is controlled. Other valves may be used if possible. As such a valve, for example, an electromagnetic negative pressure adjusting valve capable of continuously adjusting the negative pressure can be mentioned. If an electromagnetic negative pressure adjusting valve is used, the magnitude of the negative pressure provided to the vertical upper end of the main passage can be controlled to an optimum value at all times, thereby enabling on / off switching as in the case of VSV. The amount of lubricating oil supplied to the component to be lubricated can be controlled not only by adjusting the period but also by adjusting the magnitude of the negative pressure provided.

  Further, in the above-described embodiment, the suction supply means (cam supply mechanism, bearing supply mechanism) that sucks up the lubricating oil stored in the oil reservoir by the negative pressure generated by the negative pressure generating means and supplies it to the components to be lubricated. And VSV, etc.) are used to supply lubricating oil to the components subject to lubrication of the valve train system via the valve train lubrication path, but the lubrication of the crank chamber is performed via the crank chamber lubrication path. It may be used to supply lubricating oil to the subject component. Further, in the above embodiment, the suction supply means is used for the internal combustion engine having two lubrication paths. However, the crank chamber lubrication path and the valve train lubrication path are not separated from each other. The suction supply means of the present invention may be used for an internal combustion engine. In this case, the lubricating oil is sucked up from the oil pan instead of the sub oil pan.

  Next, a lubricating oil supply device according to a second embodiment of the present invention will be described with reference to FIG. The configuration of the lubricating oil supply device in the second embodiment is basically the same as the configuration of the lubricating oil supply device in the first embodiment. However, in the second embodiment, the lubricating oil supply device is branched in the main pipe 40 of the cam supply mechanism 35. A lubricating oil passage preventing device 54 as shown in FIG. 7 is arranged on the VSV 37 side of the branch portion to the pipe 41, that is, vertically above the branch portion.

  The lubricating oil passage prevention device 54 includes a housing 55 disposed in the main pipe 40 and a lubricating oil passage prevention member 56 accommodated in the housing 55. The lubricating oil passage prevention member 56 is formed of a material that does not allow liquid (for example, lubricating oil) and gas (for example, air) to pass therethrough, and is configured in a bellows shape. One end of the bellows-like lubricating oil passage preventing member 56 is connected to the housing 55, and the space separation plate 56a is connected to the other end. Accordingly, as the bellows of the lubricating oil passage preventing member 56 expands and contracts, the space separation plate 56 a moves in parallel in the axial direction of the housing 55, that is, in the axial direction of the main pipe 40. Specifically, the lubricating oil passage preventing member 56 changes in the housing 55 between an extended state as shown in FIG. 7A and a contracted state as shown in FIG. When the lubricating oil passage preventing member 56 is in the extended state, the space separating plate 56a is in the vertically upper position in the housing 55, and the space in the housing 55 on the vertically lower side than the space separating plate 56a becomes wider. On the other hand, when the lubricating oil passage preventing member 56 is in the contracted state, the space separating plate 56a is in the vertically lower position in the housing 55, and the space in the housing 55 vertically below the space separating plate 56a is narrowed.

  In the lubricating oil passage prevention device 54 configured as described above, when the VSV 37 is turned on and the pressure at the end of the main pipe 40 on the VSV 37 side is made negative as shown in FIG. The separating plate 56a is sucked up to the VSV 37 side, and the lubricating oil passage preventing member 56 is in the extended state as shown in FIG. As a result, the pressure in the main pipe 40 closer to the sub oil pan 30 than the lubricating oil passage prevention device 54 is lowered, and therefore the lubricating oil is sucked up vertically from the sub oil pan 30 in the main pipe 40.

  On the other hand, as shown in FIG. 5B, when the VSV 37 is turned off and the pressure at the end of the main pipe 40 on the VSV 37 side is set to atmospheric pressure, the space separation plate 56a is pushed down to the sub oil pan 30 side. Then, as shown in FIG. 7B, the lubricating oil passage preventing member 56 is in a contracted state. That is, the lubricating oil is moved vertically downward by gravity, whereby the pressure in the main pipe closer to the sub oil pan 30 than the space separating plate 56a is lowered, and accordingly, the space separating plate 56a is moved to the sub oil pan 30. Pushed down to the side. At this time, as shown in FIG. 5B, the lubricating oil is supplied to the intake cam 15a and the like via the branch pipe 41.

  Thus, even if the lubricating oil passage prevention device 54 is provided in the main pipe 40, the cam supply mechanism 35 operates in the same manner as when the lubricating oil passage prevention device 54 is not provided, and the cam supply mechanism 35 sucks the lubricating oil. Supplied to the cam 15a and the like.

  On the other hand, if a mist of lubricating oil or the like enters the VSV 37 or the negative pressure generator 38, the devices 37, 38 may not operate correctly and the reliability of these devices may be lost. On the other hand, according to the present embodiment, the provision of the lubricating oil passage prevention device 54 prevents the lubricating oil mist from flowing beyond the lubricating oil passage prevention member 56. Therefore, the lubricating oil passage preventing device 54 prevents the lubricating oil mist and the like from entering the VSV 37, the negative pressure generating device 38, and the like.

  The amount by which the lubricating oil passage preventing member 56 can be expanded and contracted is determined when the lubricating oil passage preventing device 54 is manufactured. Therefore, no matter how the negative pressure in the main pipe 40 on the VSV 37 side becomes larger than the lubricating oil preventing member 56, the lubricating oil passage preventing member 56 is more fully extended as shown in FIG. Will not stretch. For this reason, even if the negative pressure in the main pipe 40 on the VSV 37 side with respect to the lubricating oil preventing member 56 becomes larger, the amount of lubricating oil sucked up is constant. That is, according to the present embodiment, the amount of lubricating oil supplied to the intake cam 15a and the like when the VSV 37 is turned on once is constant. Therefore, the amount of lubricating oil supplied to the intake cam 15a and the like can be controlled by changing the cycle for turning on / off the VSV 37.

  The lubricating oil passage prevention device 54 may be used in the bearing supply mechanism 36. In this case, the lubricating oil passage prevention device 54 is disposed in the upper pipe 50.

It is side surface sectional drawing of the internal combustion engine provided with the lubricating oil supply apparatus of this invention. It is the elements on larger scale of the A section of FIG. It is a diagram which shows the lubricating path for crank chambers. It is a schematic top view of a cylinder head. FIG. 5 is a diagram schematically showing a cam supply mechanism in a cross section of the cylinder head taken along line V-V in FIG. 4. FIG. 5 is a diagram schematically showing a bearing supply mechanism in a cross section of a cylinder head along line VI-VI in FIG. 4. It is a figure which shows a lubricating oil passage prevention apparatus.

Explanation of symbols

15 intake camshaft 26 valve lifter 33 journal bearing 35 cam supply mechanism 36 bearing supply mechanism 37 vacuum switching valve (VSV)
38 Negative pressure generator 40 Main pipe (main passage)
41 Branch pipe (branch passage)

Claims (6)

In a lubricating oil supply apparatus that supplies lubricating oil to components to be lubricated in an internal combustion engine,
Oil reservoir for storing lubricating oil, negative pressure generating means for generating negative pressure, and components to be lubricated by sucking up the lubricating oil stored in the oil reservoir by the negative pressure generated by the negative pressure generating means A lubricating oil supply device comprising sucking and supplying means for supplying to the oil.   A crank chamber lubrication path for lubricating the components to be lubricated in the crank chamber, and a valve train system for lubricating the components to be lubricated in the valve system, which are separate from the crank chamber lubrication path The suction suction supply means is used only to supply lubricating oil to the components to be lubricated of the valve system via the valve system lubrication path. Item 2. The lubricating oil supply device according to Item 1.   The suction supply means includes a negative pressure control valve that controls the magnitude of the negative pressure generated by the negative pressure generation means, and the suction pressure supply valve controls the magnitude of the negative pressure by the negative pressure control valve. The lubricating oil supply device according to claim 1 or 2, wherein the amount of lubricating oil supplied from the supplying means to the component to be lubricated is controlled.   A negative passage generated by the negative pressure generating means, comprising: a main passage communicating with the negative pressure generating means and the oil reservoir; and a branch passage branched from the main passage and extending toward the components to be lubricated. When pressure is provided to the main passage, the negative pressure causes the lubricating oil to be sucked up vertically above the branching portion to the branch passage, and to the main passage having the negative pressure generated by the negative pressure generating means. When the supply of the oil is stopped, at least part of the lubricating oil sucked up vertically above the branch portion is supplied to each component to be lubricated via the branch passage. The lubricating oil supply device according to claim 1.   The lubricating oil supply device according to claim 4, wherein a lubricating oil passage preventing member that prevents passage of lubricating oil is provided on the main passage and closer to the negative pressure generating means than the branching portion to the branch passage.   The lubricating oil passage preventing member includes a space separation plate movable in the axial direction of the main passage, and the space separation plate moves according to the negative pressure provided to the main passage by the negative pressure generating means. The lubricating oil supply device according to claim 5.

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