JP4544460B2 - Hydraulic supply device for multi-cylinder internal combustion engine - Google Patents

Description

  The present invention relates to an apparatus for supplying hydraulic pressure to a hydraulic lash adjuster in each cylinder in a multi-cylinder internal combustion engine having a hydraulic lash adjuster in either one or both of an intake valve and an exhaust valve in each cylinder. Is.

  Generally, when lubricating oil in an internal combustion engine is supplied as hydraulic pressure to a hydraulic lash adjuster in each cylinder, air exists in the lubricating oil, and when this air enters the hydraulic lash adjuster together with lubricating oil, Disable its operation.

Therefore, Patent Document 1 as a prior art provides an air separation tank having an air vent hole at the top in a portion of the hydraulic path from a lubricating oil pump to the hydraulic lash adjuster higher than the hydraulic lash adjuster. The lubricating oil from the lubricating oil pump is introduced into the upper part of the air separation tank, and the air contained therein is separated and discharged from the top air vent hole, while the air is released in the air separation tank. It is proposed that the separated lubricating oil is supplied to the hydraulic lash adjuster from the lower part of the air separation tank.
JP-A-4-5406

  However, providing an air separation tank having an air vent at the top in the middle of the hydraulic path higher than the hydraulic lash adjuster thus only complicates the hydraulic path to the hydraulic lash adjuster. However, since it is necessary to secure a space for providing the air separation tank, there is a problem that the size and the weight are increased.

  In a recent internal combustion engine, for example, as described in Japanese Patent Application Laid-Open No. 2000-87716, a cam carrier is detachably attached to the upper surface of a cylinder head, and an intake valve and an intake valve are attached to the cam carrier. Focusing on the fact that a camshaft for opening and closing the exhaust valve is supported, it is a technical problem to solve this problem using this cam carrier.

In order to achieve this technical problem, the present invention
“A cylinder head having a plurality of cylinders is provided with an intake valve and an exhaust valve for each cylinder and a hydraulic lash adjuster for one or both of the intake valve and the exhaust valve. A multi-cylinder formed by mounting a cam carrier pivotally supported on the upper surface by a camshaft for opening and closing the intake valve and the exhaust valve so that the lower surface of the cam carrier is fitted with a sealing gasket or a liquid sealant applied. In an internal combustion engine,
The cylinder head is provided with a hydraulic pressure supply passage from a lubricating oil supply source and a hydraulic outlet passage to the hydraulic lash adjuster in each cylinder, and a portion of the upper surface of the cylinder head where the lower surface of the cam carrier is combined, An outlet of the hydraulic pressure supply passage and an inlet of the hydraulic pressure outlet passage are opened, and an outlet of the hydraulic pressure supply passage and an inlet of the hydraulic pressure outlet passage are formed on a mating surface of the upper surface of the cylinder head and the lower surface of the cam carrier. There are provided hydraulic grooves communicating with each other and air venting means from within the hydraulic grooves, and the air venting means is configured as a slit groove provided in the sealing gasket, or the liquid sealant is applied. No part of the structure . "
It is characterized by that.

In this configuration, the lubricating oil sent from the lubricating oil supply source such as a lubricating oil pump to the hydraulic lash adjuster flows upward from the hydraulic pressure supply passage into the hydraulic groove, flows through the hydraulic groove in the longitudinal direction thereof, It flows out downward from the outlet passage and is supplied to the hydraulic lash adjuster in each cylinder.

In other words, the lubricating oil to the hydraulic lash adjuster flows in an inverted U shape such that the lubricating oil flows upward from the hydraulic supply passage into the hydraulic groove and then flows downward from the hydraulic groove to the hydraulic outlet passage. When flowing in the groove, the air contained in the lubricating oil floats and separates from the lubricating oil and is discharged out of the passage from the air venting means. Therefore, the lubricating oil and the hydraulic lash adjuster in each cylinder It is possible to reliably prevent the air from being supplied together.

In this case, the hydraulic groove and air venting means for separating the air from the lubricating oil are provided on the mating surface of the upper surface of the cylinder head and the lower surface of the cam carrier attached to the upper surface. The hydraulic groove for air separation and the air vent means from the hydraulic groove are provided on the mating surface of the upper surface of the head and the lower surface of the cam carrier, so that the hydraulic groove, the air vent means for the hydraulic groove, It is not necessary to secure a separate space for providing the hydraulic supply passage and the hydraulic outlet passage, or to provide other parts other than the cam carrier, and the configuration of the hydraulic path to the hydraulic lash adjuster is not required. since it easily, that it and the weight to size is up, mounting the Kamukyariya the upper surface of the cylinder head To use, it can be reliably avoided.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 5 show a first embodiment.

  In this figure, reference numeral 1 denotes a cylinder block in which a plurality of cylinders 2 are arranged in the direction of the crank axis 3, and reference numeral 4 denotes a cylinder head that is fastened to the upper surface of the cylinder block 1.

  The cylinder head 4 is provided with an intake port 5 to the cylinder 2 and an exhaust port 6 from the cylinder 2 for each cylinder 2, and an exhaust valve 7 to the intake port 5 and an exhaust port to the exhaust port 6. A valve 8 is provided for each cylinder 2.

  The intake valve 7 and the exhaust valve 8 are normally kept closed by springs 9 and 10 provided on the respective valves, and one end is pivoted by hydraulic lash adjusters 11 and 12 provided on the cylinder head 4 at their upper ends. The supported rocker arms 13 and 14 are in contact with each other.

A flat upper surface 15 is formed on the top of the cylinder head 4 so as to surround the entire periphery of the top, and a plurality of cam carriers 16 configured in a frame shape are provided on the upper surface 15. As shown in FIGS. 4 to 5, a sealing gasket 17 is inserted between the lower surface of the cam carrier 16 and the upper surface 15 of the cylinder head 4. or it is, or, between the upper surface 15 of the cylinder head 4 and the cam carrier 16, as shown in FIG. 6, are sealed by a coating liquid sealant 28.
A head cover 27 is detachably attached to the upper surface of the cam carrier 16.

  The cam carrier 16 is supported by the camshaft 18 for the intake valve and the camshaft 19 for the exhaust valve so as to extend in parallel with the crankshaft 3, and one end of each of the camshafts 18, 19 is The cylinder head 4 protrudes into a chain case 20 attached to one end surface 4a, and the rotation of the crankshaft is transmitted to the cam shafts 18 and 19 through a timing chain 21 disposed in the chain case 20. On the other hand, the cam 18a in the intake valve cam shaft 18 is in contact with the rocker arm 13 for the intake valve 7, and the cam 19a in the exhaust valve cam shaft 19 is in contact with the rocker arm 14 for the exhaust valve 8. Thus, the intake valve 7 and the exhaust valve 8 are configured to open and close by the rotation of the cam shafts 18 and 19.

  The cylinder head 4 includes a hydraulic pressure supply passage 22 from a lubricating oil supply source such as a lubricating oil pump (not shown) attached to the cylinder block 1 and the like, and hydraulic lash adjusters 11 for the intake valves. And a hydraulic outlet passage 24 leading to each of the hydraulic lash adjusters 12 for the exhaust valve. The outlet in the hydraulic supply passage 22 and the inlets in both hydraulic outlet passages 23 and 24 are An opening is formed in a portion of the upper surface 15 of the cylinder head 4 adjacent to the chain case 20.

Further, a portion of the upper surface of the cylinder head 4 adjacent to the chain case 20 has a hydraulic groove 25 communicating between the outlet of the hydraulic pressure supply passage 22 and the inlets of the dedicated hydraulic outlet passages 23 and 24. And an air venting means 26 to the outside of the passage is provided so as to open in the chain case 20, and the hydraulic groove 25 and the air venting means 26 are hermetically sealed by the cam carrier 16 attached to the upper surface 15. To be configured.

In this configuration, lubricating oil from a lubricating oil supply source such as a lubricating oil pump to the hydraulic lash adjusters 11, 12 flows upward from the hydraulic supply passage 22 into the hydraulic groove 25, and the hydraulic groove 25 passes through the longitudinal direction of the hydraulic groove 25. And then flows downward from both hydraulic outlet passages 23 and 24 and is supplied to the intake valve hydraulic lash adjuster 11 and the exhaust valve hydraulic lash adjuster 12 in each cylinder.

That is, lubricating oil from a lubricating oil supply source such as a lubricating oil pump to the hydraulic lash adjusters 11 and 12 flows upward from the hydraulic supply passage 22 into the hydraulic groove 25 and then from the hydraulic groove 25 to both hydraulic outlet passages 22 and 23. When flowing in the hydraulic groove 25, the air contained in the lubricating oil floats and separates from the lubricating oil and is released from the air vent means 26 by flowing in an inverted U shape. Since the air is discharged out of the passage , air can be reliably prevented from being supplied together with the lubricating oil to the hydraulic lash adjusters 11 and 12 in each cylinder.

In this case, the from the air vent means 26, a part of the lubricating oil is ejected to the chain case 20 together with the air, the lubricating oil ejected to the chain case 20 from the air vent means 26, said chain The timing chain 21 disposed in the case 20 is used for lubrication.

In the present invention, the air venting means 26 from the hydraulic groove 25 is configured as follows.
That is, when sealing between the upper surface 15 of the cylinder head 4 and the cam carrier 16 is performed with a gasket 17 interposed therebetween as shown in FIGS. 6 is provided with a slit 17a, and the slit 17a is formed in the air vent means 26 , or a seal between the upper surface 15 of the cylinder head 4 and the cam carrier 16 is formed as shown in FIG. When the sealing agent 28 is used, the liquid sealing agent 28 is not applied only to the portion 28a having an appropriate length L in the upper surface 15 of the cylinder head 4, and the portion 28a having an appropriate length L is not applied. The air vent means 26 is configured by forming a gap in the air vent.
In the case of the latter configuration, the air vent amount from the air vent means 26 is set on the surface of the upper surface 15 of the cylinder head 4 or the lower surface of the cam carrier 16 where the liquid sealant 28 is not applied. Can be performed by changing the roughness, or by increasing / decreasing the length L in the portion where the liquid sealant 28 is not applied, or by appropriately combining them.

In addition, the air venting means 26 described above may be provided so as to be provided in the valve mechanism chamber on the upper surface of the cylinder head, instead of being provided in the chain case 20.

  In the above embodiment, the hydraulic groove 25 communicating between the hydraulic pressure supply passage 22 and the hydraulic outlet passages 23 and 24 is provided on the upper surface 15 side of the cylinder head 4. The present invention is not limited to this, and the hydraulic groove 25 is provided on the lower surface side of the cam carrier 16 or extends over both the upper surface 15 of the cylinder head 4 and the lower surface of the cam carrier 16. You may make it the structure of providing in this way.

However, when all of the hydraulic grooves 25 are provided on the upper surface 15 side of the cylinder head 4 as in the illustrated embodiment, the ceiling surface of the hydraulic grooves 25 is the upper surface of the cylinder head 4. 15 and the lower surface of the cam carrier 16 are located at substantially the same height as the air venting means 26 provided on the mating surface, while the air in the lubricating oil floats and collects on the ceiling surface. Since the air that has floated and separated on the ceiling surface can be quickly and reliably released from the air venting means, there is an advantage that the air separation performance can be further enhanced.

FIG. 3 is a longitudinal front view showing the first embodiment, and is a cross-sectional view taken along line II in FIG. 2. It is a top view of FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 2. FIG. 4 is an enlarged sectional view taken along line IV-IV in FIG. 2. It is a disassembled perspective view of the principal part in 1st Embodiment. It is a disassembled perspective view of the principal part in 2nd Embodiment.

DESCRIPTION OF SYMBOLS 1 Cylinder block 2 Cylinder 3 Crank axis 4 Cylinder head 15 Cylinder head upper surface 7 Intake valve 8 Exhaust valve 11, 12 Hydraulic lash adjuster 13, 14 Rocker arm 16 Cam carrier 17 Gasket
28 Liquid sealant 18, 19 Cam shaft 20 Chain case 21 Timing chain 22 Hydraulic supply passage 23, 24 Hydraulic outlet passage 25 Hydraulic groove 26 Air venting means 17a Notch groove
28a The part which does not apply liquid sealant

Claims (1)

A cylinder head having a plurality of cylinders is provided with an intake valve and an exhaust valve for each cylinder, and a hydraulic lash adjuster for one or both of the intake valve and the exhaust valve is provided. A multi-cylinder internal combustion engine in which a cam carrier that pivotally supports a camshaft for opening and closing the intake valve and the exhaust valve is mounted so that the lower surface of the cam carrier is fitted with a sealing gasket or a liquid sealant applied. In the institution
The cylinder head is provided with a hydraulic pressure supply passage from a lubricating oil supply source and a hydraulic outlet passage to the hydraulic lash adjuster in each cylinder, and a portion of the upper surface of the cylinder head where the lower surface of the cam carrier is combined, An outlet of the hydraulic pressure supply passage and an inlet of the hydraulic pressure outlet passage are opened, and an outlet of the hydraulic pressure supply passage and an inlet of the hydraulic pressure outlet passage are formed on a mating surface of the upper surface of the cylinder head and the lower surface of the cam carrier. There are provided hydraulic grooves communicating with each other and air venting means from within the hydraulic grooves, and the air venting means is configured as a slit groove provided in the sealing gasket, or the liquid sealant is applied. A hydraulic pressure supply device in a multi-cylinder internal combustion engine, characterized in that the configuration is not provided.

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