JPS6123818A - Valve cooling and lubricating device for internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve the output and durability of an engine, by a method wherein oil holes are formed in the press-in hole of a valve guide, and an annular oil reservoir is provided to the slide part of a valve stem. CONSTITUTION:Oil holes 11 and 12 are formed in a manner to extend through the mounting hole of a valve guide 3. An oil hole 13 is formed in communication with the oil hole 12, and connected to an oil pan 14. An annular oil reservoir 15 is located to the inner bore part of the valve guide 3. Oil holes 16 and 17 are communicated with an oil reservoir 15, and are communicated with the oil holes 11 and 12, respectively, in a condition in that the valve guide 3 is pressed in a cylinder head 1. This relieves the heat load of an exhaust valve or a valve seat and provides further suitable lubrication, resulting in further improvement of the output and durability of an engine.

Description

[Detailed description of the invention] The present invention relates to a valve cooling and lubrication system for an internal combustion engine.

Among the many components, the exhaust valve of an internal combustion engine is used under the most severe conditions. Therefore, the most important aspects of an internal combustion engine, such as maximum output and durability, are mostly limited by the exhaust valve.

The most important issues for exhaust valves used at high temperatures are improved heat resistance and cooling.

Conventionally, various efforts have been made to develop highly heat-resistant materials and improve cooling in order to improve heat resistance, but these are still insufficient and have become a bottleneck in the output and durability of internal combustion engines. In particular, for cooling exhaust valves, it is known to have a hollow interior filled with sodium. but.

Although sodium-filled valves reduce the temperature of the cap section, which is the hottest point, the temperature of the temperature rises in the system section, inhibiting lubrication of the stem section and causing problems such as increased wear and seizure. Ta.

In addition to the above-mentioned sodium-filled valve, air cooling has also been proposed to directly cool the exhaust valve.

Air cooling requires an air pressure source and has problems such as poor lubrication of the stem, so it has not been put to practical use.

The object of the present invention is to improve the cooling and lubrication of the above-mentioned sodium-filled valve, and its characteristics are that one end is opened in the press-fitting area of the valve guide of the cylinder head of a reciprocating internal combustion engine; one set of oil holes having a pressure oil inlet on the other end and a pressure oil outlet on the other end; and the one set of oil holes provided on the sliding part of the valve stem on the inner periphery of the valve guide. A lower annular oil reservoir part is provided in the sliding part of the valve stem on the inner periphery of the lower part of the valve guide and communicates with the upper space of the cylinder head. be.

In this case, since the cooling oil is pumped to the stem portion of the sodium-filled valve to cool the stem portion and at the same time provide lubrication, the above-mentioned problems are completely eliminated. Since engine system oil is used for cooling, there is no need to provide a hydraulic power source. Since the stem portion of the sodium-filled valve, which is extremely effective in cooling the cap portion of the exhaust valve at its highest temperature, is cooled with cooling oil, the stem portion further enhances the cooling effect of the cap portion.

Note that the present invention can provide thermal cooling and lubrication effects not only for sodium-filled valves but also for ordinary exhaust valves.

What is the invention? , applicable to internal combustion engines with pet valves.

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

FIG. 1 is a sectional view showing an exhaust valve cooling and lubricating device according to an embodiment of the present invention.

In the figure, the exhaust outlet portion of the cylinder head 1 has an exhaust valve seat 2. A valve guide 3 is press-fitted into the valve guide portion. A coolant 6 such as sodium is sealed in the hollow part 5 of the exhaust valve 4 in an amount of about 1/2 of the volume of the hollow part. The exhaust valve 4 is attached to the cylinder head 1 with a valve holder 7, a spring holder 8, and valve springs 9 and 10 as shown in the figure. 11 and 12 are oil holes provided through the mounting hole of the valve guide 3;
3 is an oil hole provided in communication with the oil hole 12, and communicates with a drain or an oil cooler 14. 15 is an annular oil reservoir provided in the inner diameter portion of the valve guide 3; 16. '
17 communicates with the oil sump portion 15, and when the valve guide 3 is press-fitted into the cylinder head 1, the oil holes 11 and 17 respectively communicate with the oil sump portion 15.
, No need to communicate with 12.

Figure 2 is an enlarged sectional view showing the vicinity of the pulp guide 3 in Figure 1, and Figures 3.4 and 5.6 are A-A in Figure 2, respectively.
A cross section taken along arrow B, a cross section taken along C-C, and a cross section taken along D-D are shown.

In FIGS. 2 to 6, 18 is an annular oil reservoir provided at the lower inner diameter part of the valve guide 3, and 20 is /? ) This oil passage is cut out in a part of the outer periphery of the rep guide 3, and its lower end communicates with an oil reservoir 18 through an oil hole 19, and its upper end opens at the upper end surface of the valve guide press-fit portion of the cylinder head 1.

The operation in the case of the above configuration will be described.

In FIG. 1, when the engine is operated, the exhaust valve 4 is opened and closed by a cam, tappet, bushing rod, rocker arm, etc. (not shown). Exhaust valve 4 depending on engine operation
When the coolant 6 such as IJum reaches a temperature higher than its melting temperature, it melts and becomes liquid. When the exhaust valve performs a reciprocating motion to open and close.

The internal liquid coolant 6 moves up and down in the hollow part 5 of the exhaust valve 4 and transfers the heat of the high temperature exhaust valve head to the stem part, so that the stem part becomes high temperature.

On the other hand, lubricating oil for the engine passes through an oil pump (not shown), an oil cooler, an oil filter, a pressure regulating valve, etc., and then enters an annular oil reservoir formed by a circumferential groove provided on the inner diameter of the valve guide 3 and the stem of the exhaust valve 4. Enter section 15. The stem of the exhaust valve, which is reciprocating at high temperatures, has an annular oil reservoir 1.
It is cooled and lubricated by the lubricating oil in 5. The lubricating oil in the oil reservoir 15 heated by the heat of the stem portion is drained into the oil pan 14 through oil holes 17, 12, 13. Therefore, the heat of the high-temperature exhaust valve head is transferred to the stem via the coolant 6, and the heat of the stem is cooled by the lubricating oil, so both the exhaust valve head and the stem are suitable. is cooled to When the temperature of the exhaust valve head section decreases, the temperature of the valve seat 2 also decreases, which can increase the load or improve durability. Also,
Since the stem part is cooled and lubricated at the same time, problems such as seizure and wear are completely eliminated.

However, since lubricating oil from the engine is normally used as the hydraulic pressure source in the annular oil sump 15, oil flows into the oil sump from the gap between the inner diameter of the valve guide 3 and the outer diameter of the stem of the exhaust valve 4. 15
leaks in the vertical direction. The oil leaking upward collects at the top of the cylinder head 1.

There is no problem because the oil is drained together with the oil that lubricates the valve gear. However, if the oil leaks downward from the bottom end of the pulp guide 3, it becomes a carbon medium due to the exhaust gas and contaminates the inside of the exhaust pipe and the supercharger with lubricating oil. To prevent this problem, A circumferential groove 18. Oil hole 19. Since a notch 20 communicating with the upper surface of the cylinder head 1 is provided on the outer periphery, these 18, 1
The pressure at 9.20 is the same as the pressure at the top of the cylinder head. Note that the upper surface of the cylinder head is normally at atmospheric pressure or below atmospheric pressure (when the blow pie gas in the head cover is sucked into the suction side). Further, the average pressure within the exhaust pipe is usually equal to or higher than atmospheric pressure. The oil leaking downward from the oil reservoir 15 will flow down to the circumferential groove 18 and into the oil hole 19. It flows through the notch 20 to the upper part of the cylinder head where the pressure is lower than the exhaust pipe internal pressure.

Therefore, oil does not leak from the lower end of the valve guide 3 and exit to the exhaust port. From the upper end of the valve guide 3 to the circumferential groove 1
Since the forced lubrication is completely delayed during the period 8, the wear of the pulp stem and valve guide is significantly reduced due to cooling, and the service life is extended.

FIG. 7 is a sectional view showing the main parts of another embodiment according to the present invention;
FIG. 8 is a view taken along arrow E in FIG. The upper end of the notch 20A provided on the outer periphery of the valve guide 3A is made the same as the upper end surface of the valve guide 3A to facilitate machining.
The functions are similar to those shown in FIGS. 1-6.

FIG. 9 is a sectional view showing a main part of still another embodiment of the present invention, and FIG. 10 is a view taken along arrow F in FIG. A case is shown in which a notch 20B provided on the outer periphery of the valve guide 3B is processed using a keyway cutter. The functions are similar to those shown in FIGS. 1 to 6, 7, and 8 described above.

The above description relates to cooling and lubrication of a hollow exhaust valve containing a coolant, but the present invention can provide effective cooling and lubrication not only for a hollow exhaust valve containing a coolant but also for a normal solid exhaust valve. Of course.

The above case has the following effects.

Conventionally, with regard to cooling exhaust valves, exhaust valves with coolant sealed inside and air cooling valves have been proposed.

In the former case, the temperature of the umbrella part decreases slightly, but the temperature of the stem part increases, resulting in poor lubrication of the stem part.

Problems such as seizure and increased wear occur, and the latter requires an air pressure source and the same problems as the former occur due to poor lubrication of the stem, so it is not put into practical use.

In the present invention, the heat of the hottest part (umbrella part) of the exhaust valve is effectively transferred to the stem part by the coolant sealed inside the exhaust valve, and the heat of the stem part is cooled by lubricating oil.

Both the exhaust valve head and stem are cooled. Note that when the umbrella part is cooled, the valve seat part 2 is also cooled, so the thermal load on the exhaust valve and the valve seat is reduced, and more suitable lubrication can be obtained.
Engine output and durability can be further improved.

It can also be applied to inexpensive ordinary solid exhaust valves.

By reducing the heat load and providing suitable lubrication, engine output and durability can be improved.

The present invention does not require any special equipment to be installed in the conventional engine, and only requires machining a lubricating oil passage in the conventional cylinder head and valve guide and some piping, so the cost increase is small (especially since the conventional solid valve (in case of use). However, the effects of improved output and durability are very large.

Note that the present invention can also be applied to intake valves.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an exhaust valve cooling and lubricating device according to an embodiment of the present invention, Fig. 2 is an enlarged sectional view showing the vicinity of the rep guide in Fig. 1, and Fig. 3 is a sectional view showing the vicinity of the rep guide in Fig. 4 is a sectional view taken along arrow B in FIG. 2, FIG. 5 is a sectional view taken along line C-C in FIG. 7 is a cross-sectional view showing the essential parts of another embodiment according to the present invention, FIG. 8 is a view taken along arrow E in FIG. 7, and FIG. 9 is a main part of still another embodiment according to the present invention. A sectional view showing the section, FIG.
It is a view taken along arrow F in the figure. 1... Cylinder head, 3... Valve guide, 4...
... Exhaust valve, 11, 12... Oil hole, 15... Annular oil reservoir, 18... Lower annular oil reservoir 9, 20, 2
0A20shiB... Notch. Figure 1 ↓ B Rice 6 distribution A = 77 'yt-to mouth F spear q diagram

Claims (1)

[Claims] 1. One end of each press-fit hole in the valve guide of the cylinder head of a reciprocating internal combustion engine is opened, and one end is provided with an inlet for pressure oil, and the other end is provided with a pressure oil outlet. a set of oil holes, an annular oil reservoir provided at the sliding portion of the valve stem on the inner periphery of the valve guide and communicating with the set of oil holes, and a sliding portion of the valve stem on the inner periphery of the lower part of the valve guide; 1. A valve cooling and lubricating device for an internal combustion engine, comprising a lower annular oil reservoir provided in a moving part and communicating with a cylinder head upper space.