JP2008286009A - Engine lubricating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To raise the temperature of lubricating oil, while cooling a valve. <P>SOLUTION: This invention is an engine 1-lubricating device for supplying the lubricating oil to an engine 1, and is characterized by having an oil pump 2 driven by the engine 1, a heat exchange passage 20 for flowing the lubricating oil delivered from the oil pump 2 by passing through the vicinity of a valve guide of an exhaust valve of the engine 1, and a lubricating oil supply passage 40 connected to the heat exchange passage 20 and supplying the lubricating oil to a sliding part of the engine 1. Thus, knock resistance of the engine is improved by cooling the valve, and a friction loss in a valve system sliding part can be reduced by raising the temperature of the lubricating oil. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an engine lubrication device.

  The engine includes a lubricating device that supplies lubricating oil to a sliding portion of the engine and a portion where the temperature increases.

As such a lubricating device, Patent Document 1 discloses an apparatus including an oil path for supplying lubricating oil to each part of the engine and an auxiliary cooling oil passage for supplying lubricating oil to be injected toward a valve stem of an exhaust valve. Is disclosed. The auxiliary cooling oil passage is provided in the cylinder head, and a part of the lubricating oil flowing through the oil path is supplied to the auxiliary cooling oil passage. This device cools the exhaust valve and improves knock resistance by injecting lubricating oil from the oil jet provided in the auxiliary cooling oil passage to the valve stem of the exhaust valve according to the operating conditions. ing.
JP 2006-242078 A

  However, the apparatus described in Patent Document 1 has a problem in that a new structure such as an oil jet needs to be attached around the valve system of the cylinder head, which complicates the structure. Further, the lubricating oil supplied to the auxiliary cooling oil passage and the lubricating oil supplied to the valve system sliding part are independently supplied by different pumps, and are supplied to the valve system sliding part of the cylinder head. Was supplied with a relatively low temperature lubricating oil simply sucked up from the oil pan. Therefore, there is a problem that the viscosity of the lubricating oil is large and the friction loss of the valve system sliding portion is large.

  The present invention has been made by paying attention to such a conventional problem. The valve is cooled without adding new parts to improve knock resistance, and the temperature of the lubricating oil is controlled. It is aimed to reduce the friction loss by raising before feeding to the sliding part of the system.

  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected, it is not limited to this.

  The present invention is a lubricating device for an engine (1) that supplies lubricating oil to the engine (1), and includes an oil pump (2) driven by the engine (1) and an exhaust valve (22) of the engine (1). Alternatively, the heat exchange passage (20, 30) and the heat exchange passage (20, 30) through which the lubricating oil discharged from the oil pump (2) passes through the vicinity of the valve guide (23, 33) of the intake valve (32). And a lubricating oil supply passage (40, 50) connected to supply lubricating oil to the sliding portion of the engine (1).

  In the present invention, the lubricating oil discharged from the oil pump is supplied to the engine sliding portion after flowing through the heat exchange passage passing through the vicinity of the valve guide. The temperature of the valve is a knowledge obtained by experiments by the inventors that the valve guide portion is hotter than the valve stem. Therefore, according to the present invention, heat is transferred from the valve guide to the lubricating oil, so that the valve guide that is at a high temperature can be cooled to efficiently reduce the surface temperature of the valve body.

  Further, the oil temperature of the lubricating oil rises due to the heat taken from the valve guide. As a result, the lubricating oil having reduced viscosity can be supplied to the sliding portion of the engine, so that the friction loss of the engine sliding portion can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
An engine lubrication apparatus according to a first embodiment of the present invention will be described with reference to FIGS. First, a description will be given with reference to FIG.

  FIG. 1 is a diagram showing a lubricating oil supply path for the valve train of the engine 1 according to the first embodiment of the present invention.

  An oil pump 2 driven by the engine 1 discharges the lubricating oil sucked up from an oil pan 3 provided at the bottom of the engine. The lubricating oil pressurized by the oil pump 2 is filtered by the oil filter 4 and supplied to the lubricating oil passage 10 communicating with the inside of the cylinder head 5.

  The lubricating oil passage 10 is branched at the branching portion 10a, and an exhaust-side lubricating oil passage (heat exchange passage) 20 through which lubricating oil for lubricating the exhaust-side valve system sliding portion flows, and an intake-side motion (not shown). It is divided into an intake side lubricating oil passage (heat exchange passage) through which lubricating oil for lubricating the valve system sliding portion flows.

  The exhaust side lubricating oil passage 20 is formed in the cylinder row direction from the engine front side to the rear side so as to pass through the vicinity of the exhaust valve guide (see FIG. 2) press-fitted into the cylinder head 5. The exhaust-side lubricant passage 20 is connected to an oil passage (lubricant supply passage) 40 formed in the hollow exhaust camshaft 41 after passing through the vicinity of the valve guide on the exhaust side of each cylinder. Lubricating oil supplied to the oil passage 40 of the exhaust camshaft 41 is supplied to valve-operating sliding portions such as the exhaust cams 42 formed on the exhaust camshaft 41 to lubricate the sliding portions.

  The intake side lubricating oil passage (not shown in FIG. 1) is also formed in the same manner as the exhaust side, and is connected to the oil passage (lubricating oil supply passage) of the intake camshaft through the vicinity of the intake valve guide.

  Next, the exhaust side and intake side lubricating oil passages 20 and 30 formed in the vicinity of the exhaust and intake valve guides 23 and 33 will be described in detail with reference to FIGS. FIG. 2 is a sectional view of the cylinder head 5 taken along the line II-II in FIG. FIG. 3 is a view schematically showing the exhaust-side lubricating oil passage 20 formed in the vicinity of the exhaust valve guide 23.

  As shown in FIG. 2, the cylinder head 5 is formed with an exhaust port 21 and an intake port 31 that open on the top wall of the combustion chamber 6, an exhaust valve 22 that opens and closes the opening of the exhaust port 21, and an intake port 31. And an intake valve 32 for opening and closing the opening. Further, the cylinder head 5 is provided with an exhaust camshaft 41 on which an exhaust cam 42 for opening and closing the exhaust valve 22 is formed, and an intake camshaft 51 on which an intake cam 52 for opening and closing the intake valve 32 is formed. . In the exhaust camshaft 41 and the intake camshaft 51, oil passages 40 and 50 through which lubricating oil flows are formed, respectively.

  The exhaust valve 22 is inserted into an exhaust valve guide 23 that is press-fitted into the cylinder head 5. On the wall surface of the exhaust valve guide press-fitting hole 24 into which the exhaust valve guide 23 is press-fitted, a spiral groove 25 is formed by drilling or the like. The exhaust valve guide 23 is press-fitted into the exhaust valve guide press-fitting hole 24 in which the spiral groove 25 is formed, so that the exhaust-side lubrication that spirals around the outer periphery of the exhaust valve guide 23 as shown in FIG. An oil passage 20 is formed.

  Similarly, the intake valve 32 is inserted into the intake valve guide 33, and the intake side lubricating oil that spirals around the outer periphery of the intake valve guide 33 is formed by forming a spiral groove 35 in the wall surface of the intake valve guide press-fitting hole 34. A passage 30 is formed.

  Each of the exhaust side lubricant passage 20 and the exhaust side lubricant passage 30 is formed by one passage. Therefore, the exhaust-side lubricating oil passage 20 is connected to an oil passage 40 formed inside the exhaust camshaft 41 after spirally turning around the outer periphery of the valve guide 23 of each exhaust valve 22. The intake-side lubricating oil passage 30 is connected to an oil passage 50 formed inside the intake camshaft 51 after spirally turning around the outer periphery of the valve guide 33 of each intake valve 32.

  The temperature of the exhaust valve 22 is a knowledge obtained by experiments by the inventors that the valve guide portion 23 is hotter than the valve stem portion. Therefore, heat is transferred from the exhaust valve guide 23, which is at a high temperature, to the lubricant by passing the exhaust-side lubricant passage 20 through the vicinity of the exhaust valve guide 23. Thereby, the exhaust valve guide 23 can be efficiently cooled and the temperature of the lubricating oil can be raised.

  Then, by connecting the exhaust side lubricating oil passage 20 to the oil passage 40 of the exhaust camshaft 41 after passing through the vicinity of the exhaust valve guide 23, the lubricating oil whose viscosity has decreased due to the rise in the oil temperature is supplied to the valve system. Can be supplied to the sliding part. Thereby, the friction loss of a sliding part can be reduced.

  Since the intake side has the same configuration, the vicinity of the intake valve guide 32 is not as hot as the exhaust side, but the same effect as the exhaust side can be obtained.

  In addition, by using the lubricating oil passages 20 and 30 as spiral passages around the valve guides 23 and 33, the time during which the lubricating oil flows in the vicinity of the valve guides becomes longer. Thereby, the cooling of the valve guides 23 and 33 and the temperature rise of the lubricating oil can be promoted. Further, an increase in passage resistance of the lubricating oil passages 20 and 30 can be suppressed.

  According to the present embodiment described above, the lubricating oil passages 20 and 30 are connected to the oil passages 40 and 50 of the camshafts 41 and 51 after passing through the vicinity of the valve guides 23 and 33. Thereby, since the valve guides 23 and 33 which become high temperature can be cooled and the surface temperature of a valve umbrella part can be reduced, the cooling performance of the combustion chamber 6 improves and knock resistance improves.

  Further, the oil temperature of the lubricating oil rises due to the heat taken from the valve guides 23 and 33. As a result, the lubricating oil having reduced viscosity can be supplied to the sliding portion of the valve operating system, so that the friction loss of the sliding portion can be reduced.

  Further, since each of the lubricating oil passages 20 and 30 is spirally wound around the valve guides 23 and 33, the valve guides 23 and 33 are cooled to reduce the temperature of the lubricating oil while suppressing an increase in passage resistance. Can be raised.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment of the present invention is different from the first embodiment in that the lubricating oil supply path for the valve train of the engine 1 is changed.

  FIG. 4 is a diagram showing a lubricating oil supply path for the valve train of the engine 1 according to the second embodiment of the present invention.

  In the case of the first embodiment, the temperature of the lubricating oil supplied from the oil passage 40 formed inside the exhaust camshaft 41 to the sliding portion of the valve train is higher on the engine rear side than on the front side. This is because the temperature decreases while flowing from the engine rear side to the front side. For this reason, the viscosity of the lubricating oil may be different for each cylinder.

  Therefore, in the present embodiment, as shown in FIG. 4, a passage 20 a is provided for connecting the exhaust side lubricating oil passage 20 after passing through the vicinity of the exhaust valve guide to the oil passage 40 of the exhaust camshaft 41 for each cylinder. Thereby, the dispersion | variation in the temperature of the lubricating oil for every cylinder can be reduced. The intake side has the same configuration to reduce the variation in the temperature of the lubricating oil for each cylinder.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment of the present invention differs from the first embodiment in that the lubricating oil passages 20 and 30 near the valve guide are configured to promote heat transfer to the lubricating oil. Hereinafter, the difference will be mainly described. In the following embodiments, the same reference numerals are used for portions that perform the same functions as those in the first embodiment described above, and repeated descriptions are omitted as appropriate.

  FIG. 5 is a view showing an embodiment of the exhaust side lubricating oil passage 20 in the vicinity of the exhaust valve guide according to the third embodiment of the present invention.

  As shown in FIG. 5, fins 26 that divide the inside of the lubricating oil passage 20 into two are formed in the exhaust-side lubricating oil passage 20 near the exhaust valve guide according to the third embodiment of the present invention. The fins 26 increase the contact area between the lubricating oil and the inner wall surface of the passage, so that heat transfer to the lubricating oil is promoted. Thereby, compared with 1st Embodiment, since the cooling performance around a combustion chamber improves, knock resistance improves. Further, since the temperature of the lubricating oil rises faster, the friction loss can be further reduced. A similar fin may be provided in the intake side lubricating oil path 30 in the vicinity of the intake valve guide.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG. The fourth embodiment of the present invention differs from the first embodiment in that the lubricating oil passages 20 and 30 near the valve guide are configured to promote heat transfer to the lubricating oil.

  FIG. 6 is a view showing an embodiment of the exhaust side lubricating oil passage 20 in the vicinity of the exhaust valve guide according to the fourth embodiment of the present invention.

  As shown in FIG. 6, the exhaust-side lubricating oil passage 20 in the vicinity of the exhaust valve guide according to the second embodiment of the present invention is formed so that the surface roughness of the inner wall surface thereof becomes rough. Since the surface roughness increases, the contact area between the lubricating oil and the inner wall surface of the passage increases, so that heat transfer to the lubricating oil is promoted. Thereby, compared with 1st Embodiment, since the cooling performance around a combustion chamber improves, knock resistance improves. Further, since the temperature of the lubricating oil rises faster, the friction loss can be further reduced. The wall surface of the intake side lubricating oil passage 30 near the intake valve guide may be similarly roughened.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described with reference to FIG. The fifth embodiment of the present invention differs from the first embodiment in that the lubricating oil passages 20 and 30 near the valve guide are configured to promote heat transfer to the lubricating oil.

  FIG. 7 is a view showing an embodiment of the exhaust-side lubricating oil passage 20 in the vicinity of the exhaust valve guide according to the fourth embodiment of the present invention.

  As shown in FIG. 7, the exhaust-side lubricating oil passage 20 near the exhaust valve guide according to the fourth embodiment of the present invention has a plurality of small protrusions 27 formed on the inner wall surface thereof. By forming such small protrusions 27, the contact area between the lubricating oil and the inner wall surface of the passage is increased, so that heat transfer to the lubricating oil is promoted. Thereby, compared with 1st Embodiment, since the cooling performance around a combustion chamber improves, knock resistance improves. Further, since the temperature of the lubricating oil rises faster, the friction loss can be further reduced. When the small protrusion 27 is formed on the inner wall surface of the exhaust-side lubricating oil passage 20, it is desirable to form it by casting instead of drilling. A similar small protrusion may be provided in the intake side lubricating oil path 30 in the vicinity of the intake valve guide.

  Note that the present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

  For example, in the above embodiment, the lubricating oil passages 20 and 30 in the vicinity of the valve guide are spirally wound around the valve guides 23 and 33. However, as shown in FIG. 8, for example, the exhaust side lubricating oil passage 20 is formed along the valve guide 23 so as to extend in parallel with the axial direction of the valve guide 23, and then is curved to be the outer peripheral surface of the valve guide 23. May be formed so as to extend in the axial direction of the valve guide 23. Further, as shown in FIG. 9, the exhaust-side lubricating oil passage 20 may be formed so as to swell from the bottom to the top (or from the top to the bottom) along the valve guide 23. Even in such a lubricating oil passage 20, since the time during which the lubricating oil flows in the vicinity of the valve guide becomes long, the valve guide 23 can be cooled and the temperature of the lubricating oil can be raised. Needless to say, the intake-side lubrication passage 30 may be formed similarly.

  Further, although the lubricating oil passage that passes through the vicinity of the valve guide is formed on both the intake side and the exhaust side, only one of them may pass through the vicinity of the valve guide. It should be noted that the effect on the knock resistance and the lubricity of the valve train is greater when it is formed on the exhaust side where the temperature is relatively high.

It is the figure which showed the lubricating oil supply path | route with respect to the valve operating system of the engine by 1st Embodiment. It is sectional drawing of the cylinder head 5 which follows the II-II line of FIG. It is a figure which shows typically the lubricating oil channel | path formed in the valve guide vicinity. It is the figure which showed the lubricating oil supply path | route with respect to the valve operating system of the engine by 2nd Embodiment. It is the figure which showed one form of the lubricating oil channel | path near the valve guide by 3rd Embodiment. It is the figure which showed one form of the lubricating oil passage of the valve guide vicinity by 4th Embodiment. It is the figure which showed one form of the lubricating oil passage of the valve guide vicinity by 5th Embodiment. It is a figure which shows typically the lubricating oil channel | path formed in the valve guide vicinity. It is a figure which shows typically the lubricating oil channel | path formed in the valve guide vicinity.

Explanation of symbols

1 Engine 20 Exhaust side lubricating oil passage (heat exchange passage)
20a A passage connecting the heat exchange passage and the lubricating oil supply passage 22 Exhaust valve 23 Exhaust valve guide (valve guide)
26 Fin 27 Small protrusion (protrusion)
30 Intake side lubricating oil passage (heat exchange passage)
32 Intake valve 33 Intake valve guide (valve guide)
40 Oil passage in exhaust camshaft (lubricating oil supply passage)
50 Oil passage in intake camshaft (lubricant supply passage)

Claims (11)

In an engine lubrication system that supplies lubricating oil to an engine,
An oil pump driven by the engine;
A heat exchange passage through which the lubricating oil discharged from the oil pump passes through the vicinity of the valve guide of the exhaust valve or intake valve of the engine;
A lubricating oil supply passage connected to the heat exchange passage for supplying lubricating oil to the sliding portion of the engine;
An engine lubrication device comprising: 2. The engine lubrication device according to claim 1, wherein the heat exchange passage spirally surrounds an outer periphery of the valve guide. 3. 3. The engine lubrication device according to claim 2, wherein the heat exchange passage is a spiral groove formed in an inner wall surface of the press-fitting hole of the valve guide. 2. The engine lubrication device according to claim 1, wherein the heat exchange passage extends in parallel with an axial direction of the valve guide. 5. The engine lubrication device according to claim 4, wherein the heat exchange passage is a groove formed in an inner wall surface of the press-fitting hole of the valve guide and extending in parallel with the axial direction of the valve guide. 6. The engine lubrication device according to claim 1, wherein the heat exchange passage includes fins that increase a contact area between the passage inner wall surface and the lubricating oil on the inner wall surface of the passage. . 6. The engine lubrication device according to claim 1, wherein the heat exchange passage includes a protrusion on the inner wall surface of the passage that increases a contact area between the inner wall surface of the passage and the lubricating oil. . The engine lubricating device according to any one of claims 1 to 7, wherein a surface roughness of an inner wall surface of the heat exchange passage is made rougher than that of the lubricating oil supply passage. The engine lubrication device according to any one of claims 1 to 8, wherein a passage connecting the heat exchange passage and the lubricating oil supply passage is provided for each cylinder of the engine. 10. The lubricating oil supply passage according to claim 1, wherein the lubricating oil supply passage is an oil passage formed in a camshaft that supplies lubricating oil to a valve-system sliding portion of the engine. The engine lubrication device described. 11. The engine lubrication device according to claim 1, wherein the heat exchange passage is a passage extending in a cylinder row direction of the engine.