FI104111B - Reciprocating piston for internal combustion engine - Google Patents

Description

104111

Reciprocating piston for internal combustion engine

The invention relates to a reciprocating piston of an internal combustion engine having a plurality of clamping rings and an oil scavenging ring located directly below them, having pressure relief grooves leading from the groove of this oil ring into the piston and an oil connecting groove below More particularly, the invention relates to a reciprocating piston of an internal combustion engine according to the preamble of claim 1.

10 This type of piston is previously known as DE-PS 927 544 Ace below the oil ring in each directional quarter before each end face of the piston pin has one oil cone groove. This is intended to remove excess lubricating oil in these areas before entering the combustion chamber. However, it has been shown that high-loaded piston-15 nipples exhibit an oil shortage in the directional quarters before the piston rod lengths. In these piston types, oil supply from the directional quarters upstream of the piston rod ends is prevented by the limited oil circumference groove and large oil outlet openings at both ends.

It is an object of the invention to provide an improved version of the piston of the type mentioned at the outset, so that sufficient oil supply to the piston rings and the outer surfaces of the piston is achieved throughout their entire range.

: "This object is achieved by employing the procedures described in the symbols of claim 1.

;, J .; The advantages of the invention are that the pressure of the gas in the directional quarters before the longitudinal sides of the piston pin can be intentionally: ···! lowers. Thus, there is no pressurized combustion gas below these oil rings in these areas which could, on the one hand, counteract the lateral passage of oil to the directional quarters prior to the piston pin lengths and on the other hand lead to oil adhering to the 30 cylinder wall. The surrounding oil cone groove may list here the extra lateral movement of the oil before the end of the piston pin. As a result, some of this oil can pass unhindered to the surrounding oil :. i. · using a groove for the direction quarters before the piston rod length pages. In contrast, the remainder of the oil is introduced into the piston. As a result, the oil cannot create a flow rate so high that the ring groove below the oil ring or the oil ring • · 2 104111 is shaped to allow oil to penetrate between the ring and the cylinder liner wall. In both cases, the oil enters the combustion chamber where it burns.

With the help of the figures two examples according to the invention are shown.

Figure 1 is a horizontal sectional view of the piston; Figure 2 is a sectional view taken along line II-II of Figure 1; Figure 3 is a sectional view along line III-III of Figure 1; Fig. 4 shows a horizontal section according to another example and Fig. 5 shows another example, also in a horizontal section with respect to the piston 10.

The piston of Figures 1-3 has an upper part 1 having a plurality of grooves 2 for each press ring 3. The upper part 1 is attached to the lower part 4 in a manner known per se, which is not further explained here. The lower part 4 has a groove 5 for the oil ring. The groove 5 could in principle also be located at the top of the piston 15. Nor is the invention limited to two-piece pistons. The lower portion further receives the piston pin, the longitudinal axis of which is illustrated by A-A.

A plurality of pressure relief openings 7 emerge from the rear wall of the groove 5.

Immediately below the groove 5 for the oil ring 6, there is a surrounding oil groove 10 on the outside of the piston. Suitably, the oil groove 10: 25 cuts the groove 5. In the center of each quarter quarter b, the front end of the piston pin extends from also descend to the perpendicular outlet 8. In the illustrated example, one pressure relief opening 7 and one oil drain opening 11 are each lowered to one common outlet 8.

: 30 If, for example, the piston moves downward during the movement, it will make a • · · ^ tilt movement about axis A-A of the piston pin. This tilt movement causes the gap between the cylinder sleeve and the piston to initially decrease in the area of one direction quarter ai, later in the area a second direction during the tipping. Therefore, in these areas, the oil adhering to the cylinder sleeve compresses sideways in the direction-35 quarters b. This effect can be further enhanced by the piston * *. . is of oval cross section, i.e., its diameter measured from the center of the quarters a is greater than it from the center of the quadrants b, which is common for high-loaded pistons of large diesel engines.

By means of the piston tipping movement, larger free spaces can be momentarily created between the cylinder sleeve and the piston ring in the region of the directional quarters, through which the combustion gases may pass through the piston rings, alternately. This causes downward gas flows in the directional quarters a. However, the depressurization apertures 7 in the center quadrature a prevent the combustion gases which attempt to lead the oil in the 10-cylinder sleeve downwards to remain at the bottom of the lower compression ring 3. 6 below. Thus, a region of low pressure is created here.

The surrounding oil cone groove 10 further ensures that the oil under pressure in the oil ring 6 in the direction quarters b fills the oil cone groove 10 in the direction quarters b and can thus flow in the direction of the direction quarters a. This flow is possible because the directional quarters a do not have a back pressure of the fuel gas. the increase in oil pressure in the directional quarters b below the oil ring 6 to the extent that it could lift this ring from the cylinder wall is prevented by the oil drain openings 11. They have a diameter of 20 millimeters in diameter so that no oil pressure can be generated to raise the wreck of the 6-cylinder oil ring.

Since both the oil outlet openings 11 and the pressure relief openings 7 lead to the same outlet openings 8, it is possible to drain the oil under the piston, since the flow of the combustion gases, irrespective of the movement of the piston, is parallel to the desired oil outlet direction. Due to the smaller diameter 9 located in each oil outlet 7, during the piston machining movement: the oil contained in the oil outlet 7 cannot be returned to the outside of the piston due to the higher pressure of the exhaust gases 8.

The model of Figure 4, unlike the example described above, has only a single depression hole 12 in each direction quarter a in each direction a. 12. Each pressure reduction hole descends to the outlet 13. The outlet 13 also leads to two oil outlet 14s, which in turn, in the middle region of the directional chords b, they exit the oil conveying groove 15.

When, in the examples described above, the oil outlet and pressure relief ports are each located in a projection perpendicular to each other, it is shown in Figure 5 that the oil outlet holes 17 and the pressure relief holes 16 are pro-. . when viewed as a jection can also be located at a larger angle to each other. This • I · 4 104111 can be an interesting option when, for example, the openings in the screws connecting the top and bottom of the piston have to be rotated. In this design, again, one appropriate drainage port 17 and one depressurization port 16 are, in each case, suitably led to one common outlet port 18.

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Claims (2)

5, 104111 A reciprocating piston of an internal combustion engine having a plurality of clamping rings (3) and an oil scavenging ring (6) immediately below them, 5 oil drain openings (11; 14; 17) below the oil scavenging ring (6; 14); leading into the piston and each located in the piston cross-section quarter quarter (b) defined by the end surface of the piston pin, characterized in that a surrounding oil drain groove (10; 15) is provided below the oil scavenging ring (6); it will be seen that pressure relief openings (7; 12; 16) are provided in the groove (5) of the oil scavenging ring (6) for venting the combustion gases, which are located in the central region 15 of the directional quarter (a) defined by the piston. from the pressure and back pressure sides, that at least one oil drain opening (11; 14; 17) and at least one pressure relief opening (7; 12; 16) opens into a single common outlet (8; 13; 18), 20 and that each pressure relief opening (7; 12; 16) has an area having a throttle bore (9). Submersible plunger according to Claim 1, characterized in that the oil conveying groove (10) extends parallel to the piston axis to the groove (5) of the oil scavenging ring (6). · 1 I · · • «· -::: • · · • · 1 • · · m 9 9 • · · • 1» • 9 6 104111