JPS6139051Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylinder head oil cooling system for an engine.

Conventional double overhead camshaft engine (hereinafter referred to as DOHC engine)
In this system, intake and exhaust camshafts are provided, and oil is supplied separately to the respective journal parts and cam sliding surfaces to lubricate them, and the oil is returned to the oil pan by natural fall. There is. That is, in this DOHC engine, the intake and exhaust lubrication systems are separate, and the cylinder head is cooled by this oil.

The present invention is intended to provide a cylinder head oil cooling device for the engine having the above structure, which can achieve a better cooling effect by guiding the oil that has lubricated the intake side to the exhaust side.

The present invention provides a cylinder head for a DOHC engine, in which an oil passage is provided from the intake side lubricating passage to the exhaust side of the cylinder head, and the passage guides oil that has lubricated various parts on the intake side to the exhaust side. It is an oil cooling device.

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

1 and 2 show a plan view and a side sectional view of a cylinder head in a two-valve engine, in which 1 is an intake passage, 2 is an exhaust passage, 3 is a valve,
4 is a tappet, 5 is a cam provided on the camshaft, and 6 is a tappet pressure relief hole communicating with the cam chain passage. 11 is a lubricating oil discharge port provided on the intake side, 12 is the same oil discharge port on the exhaust side, 13,
14 is a camshaft journal bearing portion, 15, 1
6, 17, and 18 are cam chambers, 19 is a cam chain passage, and 20 is an oil passage leading from the cam chamber 15 to the tappet pressure relief hole 6 at the upper part of the exhaust passage. A tubular passage is formed between the head cover (not shown) and the head cover (not shown). 21 is a tappet pressure relief hole 6 at the upper part of the exhaust passage from the cam chamber 16.
It is a tubular oil passage leading to the

Note that FIG. 2 shows the inclination with respect to the horizontal plane L when the engine is actually mounted on the vehicle body.

First, oil discharged from the oil discharge port 11 on the intake side is supplied to the camshaft journal bearing 13 and the cam chambers 15 and 16 as shown by the arrow, and excess oil passes through the cam chain passage 19 to the oil pan (Fig. (not shown). This lubricates the camshaft journal and cam sliding surface on the intake side. On the other hand, a part of this oil flows into the oil passage 2 which opens into the cam chambers 15 and 16.
0 and 21 to reach the upper part of the exhaust passage 2 as shown by the arrow, and a tappet pressure relief hole 6 opened there.
It then flows out to the oil pan via the cam chain passage 19.

Also, the oil discharged from the oil discharge port 12 on the exhaust side flows as shown by the arrow, is supplied to the cam chambers 17 and 18, and lubricates the camshaft journal and cam sliding surface on the exhaust side as well as on the intake side. do. And the oil goes to the cam chain passage 19 as shown by the arrow.
It then falls into the oil pan.

In addition, in the case of a 4-valve engine, oil reaches the upper part of the intake passage from the camshaft journal bearing part and cam chamber on the intake side, and from there an oil passage is provided to the exhaust side, which allows the oil to flow to the upper part of the exhaust passage. It is sufficient that the oil that lubricates the journal part on the exhaust side and the cam sliding surface flows out from the cam chain passage into the oil pan.

As described above, according to the present invention, a separate oil passage is provided from the lubrication passage on the intake side of the cylinder head to the exhaust side, and the oil used for lubrication on the intake side is guided to the exhaust side by the oil passage. As a result, the amount of oil flow in the cylinder head increases, and therefore the amount of oil flowing in the cylinder head increases.
In particular, the cooling effect of the exhaust section can be improved. Furthermore, there is no need to adjust the amount of oil distributed on the intake side and exhaust side, which was required in the past.

[Brief explanation of drawings]

FIG. 1 is a plan view schematically showing a cylinder head to which the present invention is applied, and FIG. 2 is a cross-sectional explanatory view of the same side. 1...Intake passage, 2...Exhaust passage, 3...Valve, 5...Cam, 11, 12...Oil discharge port,
15, 16, 17, 18...Cam chamber, 20, 21
...Oil passage.

Claims (1)

[Scope of utility model registration request] A cylinder head oil cooling device for a DOHC engine, characterized in that an oil passage is provided from the intake side lubricating passage of the cylinder head to the exhaust side, and the passage guides oil that has lubricated various parts on the intake side to the exhaust side.