JPH0561408U - Valve drive for internal combustion engine - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to suppress wear of a valve lifter and a push rod in a valve train of an internal combustion engine. [Structure] The push rod 2 is annularly brought into contact with the saucer portion 11 of the valve lifter 1 to form a gap 13 between the push rod 2 and the bottom portion 11a of the saucer portion 11, and the oil escapes to the bottom portion 11a of the saucer portion 11. The hole 14 is opened.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement in a valve train of an internal combustion engine.

[0002]

[Prior Art]

 A conventional valve operating system for an internal combustion engine is shown, for example, in FIG. 3 (see Japanese Utility Model Laid-Open No. 59-177709).

To explain this, the rotation of the cam 3 causes the valve lifter 1 to reciprocate, and the rocker arm 4 is swung via the push rod 2 that comes into contact with the pan portion 11 of the valve lifter 1 to open an intake / exhaust valve (not shown). It is designed to open and close.

An oil supply port 19 is formed in the valve lifter 1, and oil supplied from the oil supply port 19 lubricates a sliding contact portion between the push rod 2 and the valve lifter 1, and this oil is opened to a side wall portion 16 of the valve lifter 1. It is designed to be discharged from the oil escape hole 12.

[0005]

[Problems to be solved by the device]

 However, in such a conventional device, as shown in FIG. 4, since the oil escape hole 12 for allowing the oil after lubrication to escape is formed in the side wall portion 16 above the pan portion 11, carbon sludge or the like is formed. Was likely to be deposited on the saucer portion 11, and there was a possibility that the saucer portion 11 and the push rod 2 would be worn out earlier.

The present invention focuses on the above problems and aims to suppress the wear of the valve lifter and the push rod.

[0007]

[Means for Solving the Problems]

 The present invention relates to a valve operating system for an internal combustion engine, which includes a valve lifter driven by a cam and a push rod that moves back and forth in contact with a receiving portion of the valve lifter, and pushes a push rod in an annular contact with the receiving portion. A gap is formed between the rod and the bottom of the pan, and an oil escape hole is opened in the bottom of the pan.

[0008]

[Action]

 The oil that lubricates the sliding contact part of the valve lifter and the push rod is quickly discharged through the oil escape hole from the gap defined between the receiving part and the push rod, and the carbon sludge, etc. is discharged to the receiving part. Prevents accumulation and prevents wear on the pan and push rod.

The push rod does not interfere with the opening of the oil escape hole by bringing the push rod into annular contact with the pan.

[0010]

【Example】

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

As shown in FIG. 1, the valve lifter 1 moves back and forth in the up and down direction by a cam (not shown), and the push rod 2 comes into contact with the pan 11 of the valve lifter 1 and reciprocates to move on the cylinder head. The intake / exhaust valves are opened / closed via a rocker arm provided. A follower 5, which is in sliding contact with the cam, is fixed to the lower end of the valve lifter 1.

The receiving portion 11 of the valve lifter 1 is formed in a hemispherical shape that is curved with a predetermined curvature, and the push rod 2 is slidably contacted thereto.

The push rod 2 has its tip 2 a curved with a curvature larger than that of the saucer portion 11, and contacts the saucer portion 11 in an annular shape. A gap 13 is formed between the tip 2a of the push rod 2 and the bottom 11a of the tray 11.

The valve lifter 1 is formed with a first oil escape hole 12 opening to a side wall portion 16 above the pan 11 and a second oil escape hole 14 opening to a bottom 11 a of the pan 11.

In this case, the second oil escape hole 14 is inclined downward from the pan 11 so that the oil in the pan 11 can flow down by gravity. The second oil escape hole 14 may be formed so as to extend horizontally from the pan portion 11.

Next, the operation will be described.

Oil is supplied into the valve lifter 1 from a lubricating passage (not shown) to lubricate the sliding contact portion between the tray portion 11 and the push rod 2. A part of this oil is discharged through the first oil escape hole 12 and the rest is quickly passed through the second oil escape hole 14 from the gap 13 defined between the push rod 2 and the bottom of the pan 11. The carbon sludge and the like are prevented from being deposited on the bottom portion 11a of the tray portion 11 and the abrasion of the tray portion 11 and the push rod 2 is suppressed.

By making the push rod 2 annularly contact the pan portion 11, the push rod 2 does not interfere with the opening of the second oil escape hole 14. Further, the position adjustment of the valve lifter 1 and the push rod 2 can be easily performed.

Next, in another embodiment shown in FIG. 2, the follower 6 that comes into sliding contact with the cam of the valve lifter 1 is formed in an umbrella shape, and can be applied to a relatively large cam.

[0020]

[Effect of the device]

 As described above, according to the present invention, the push rod is annularly contacted with the pan of the valve lifter to form a gap between the push rod and the bottom of the pan, and the oil escape hole is formed in the bottom of the pan. Since it is opened, the oil that lubricates the sliding contact part of the pan and push rod is quickly discharged through the oil escape hole from the gap defined between the two parts, and carbon sludge, etc. will accumulate on the bottom part of the pan. To prevent wear on the pan and push rod.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing another embodiment.

FIG. 3 is a cross-sectional view showing a conventional example.

FIG. 4 is a sectional view of the same main portion.

[Explanation of symbols]

 1 Valve Lifter 2 Push Rod 11 Saucet 11a Bottom 13 Gap 14 Second Oil Relief Hole

Claims (1)

[Scope of utility model registration request] 1. A valve operating system for an internal combustion engine, comprising: a valve lifter driven by a cam; and a push rod that reciprocates in contact with a tray portion of the valve lifter. The push rod is brought into annular contact with the tray portion. A valve operating device for an internal combustion engine, characterized in that a gap is formed between the bottom of the receiving tray and the bottom of the receiving tray, and an oil escape hole is opened in the bottom of the receiving tray.