JPH04107571U - Piston for internal combustion engine - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the piston skirt from seizing on the cylinder wall due to lack of lubrication, and to reduce the consumption of lubricating oil. [Structure] An oil reservoir chamber 7A (7B) that opens at the bottom of the oil ring groove 4 is provided on the radial side of the oil ring groove 4 inside the piston body 1, and this oil reservoir chamber 7A (7B) is provided with a scarf. An oil supply passage 10A (10B) that communicates with the outer circumference of the piston body 1
installed inside. Then, the lubricating oil scraped off by the oil ring 6 when the piston descends is removed from the oil reservoir chamber 7A.
(7B) and oil supply passage 10 when the piston rises.
A (10B) is supplied to the outer circumference of the skirt portion 9 to lubricate the cylinder wall and the outer circumference of the skirt portion 9,
The lubricating oil scraped off by the oil ring 6 when the piston rises is stored in the oil reservoir chamber 7A (7B), and the pressure ring 5
This prevents the piston from overflowing into the space around the piston between the oil ring 6 and the oil ring 6 and flowing into the combustion chamber.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to an improvement of a piston for an internal combustion engine.

0002

[Conventional technology]

Generally, in pistons for internal combustion engines, a One or more pressure rings and one or more oil rings are parallel to each other through grooves. The oil ring is placed below the pressure ring. And oil The ring provides sliding resistance against the cylinder wall when the piston moves down (up) inside the cylinder. The oil ring moves up and down in the oil ring groove using a resistor, and is closely supported on the upper (lower) surface of the oil ring groove. scrapes unnecessary lubricating oil from the cylinder wall to form an oil film and prevents it from flowing into the combustion chamber. To prevent.

0003 Conventionally, as pistons for internal combustion engines, oil was applied to the outer circumference of the skirt of the piston body. A small hole is drilled inside the piston body to communicate the ring groove, or the piston A groove-shaped notch is cut out between the lower surface of the oil ring groove on the main body and the outer peripheral surface of the skirt. Before moving up and down in the oil ring groove, A piston that opens and closes using an oil ring is known (Japanese Publication Act, 1973). (Refer to Publication No.-49398).

0004

[Problem that the idea aims to solve]

However, when the piston rises, the upper end opening of the small hole or groove-like notch is filled with oil. The oil ring is closed from the cylinder wall when the piston rises. The lubricating oil that has been scraped off and accumulated in the oil ring groove is removed through the small hole or groove-shaped notch. It does not flow through the piston body to the outer periphery of the skirt part of the piston body, and it does not flow inside the oil ring groove. There is not enough space to store the scraped lubricating oil.

[0005] Therefore, when the piston rises, the cylinder wall and the outer circumference of the skirt are lubricated with lubricating oil. Also, the lubricating oil scraped off when the piston rose overflowed from the oil ring groove. and flows into the combustion chamber through the space around the piston between the pressure ring and the oil ring. However, this method could not avoid the inconvenience of increasing the amount of lubricating oil consumed.

[0006] This idea was made to solve the above problem, and when the piston rises, the cylinder It effectively lubricates the outer periphery of the jacket wall and skirt part, and allows lubricating oil to flow into the combustion chamber. The purpose is to reliably prevent the entry of

[0007]

[Means to solve the problem]

The internal combustion engine piston according to this invention has an oil ring groove inside the piston body. An oil reservoir chamber that opens at the bottom of the oil ring groove is provided on the radial side of the oil ring groove. In addition, the oil supply passage that communicates this oil reservoir chamber with the outer periphery of the skirt section is installed at the piping. It is characterized by being provided on the stone body.

[0008]

[Effect]

According to its structure, the lubricating oil scraped by the oil ring when the piston descends is removed. The oil is stored in the oil reservoir chamber, and when the piston rises, the oil is passed through the oil supply passage. It can be supplied to the outer periphery of the skirt portion to lubricate the cylinder wall and the outer periphery of the skirt portion.

[0009] In addition, the lubricating oil scraped off by the oil ring when the piston rises is removed from the oil pool. It accumulates in the oil chamber and overflows to the space around the piston between the pressure ring and the oil ring. You can definitely prevent this from happening.

0010

【Example】

An embodiment of this invention will be described below with reference to FIGS. 1 and 2.

[0011] Figures 1 and 2 show the thrust side and anti-thrust side of the piston when they are raised, respectively. FIG. 4 is a longitudinal sectional view showing the state and the state at the time of descent.

0012 1 in the figure shows a piston body, and the outer circumference of the crown part 2 of this piston body 1 has a bottom. One or two pressure ring grooves 3 and one oil ring groove 4 formed in the annular groove are arranged in parallel. It is set up. Then, the pressure ring 5 is inserted into the pressure ring groove 3, and the oil An oil ring 6 is inserted into the ring groove 4.

[0013] Oil ring groove inside the piston body 1 (more precisely, inside the crown part 2, the same applies hereinafter) On the radial side from 4, there is an oil ring groove 4 with a diameter within the width of the oil ring 6. A hole-shaped oil reservoir chamber 7A opening in the center of the bottom of the thrust side and anti-thrust side At least one perforation is provided on each side.

[0014] Further, on both sides of the bottom surface of the oil ring groove 4, A continuous ring receiving portion 8 is formed.

[0015] Furthermore, the piston body 1 is provided with the oil reservoir chamber 7A in the skirt of the piston body 1. - A hole-shaped oil supply passage 10A communicating with the outer periphery of the bottom part 9 is diagonally bored. There is.

[0016] The piston configured as described above is inserted into the cylinder 11 and its crown portion is 2 forms a part of the combustion chamber, and moves up and down in response to combustion pressure on the top surface of the crown part 2. Rotate the crankshaft via the connecting rod.

[0017] When the piston descends, the oil ring is closely supported on the upper surface of the oil ring groove 4, as shown in Figure 2. The lubricating oil is scraped off from the cylinder wall by the oil ring 6, and this lubricating oil is The oil flows into the oil reservoir chamber 7A provided at the bottom side of the ring groove 4 and accumulates therein. and , when the piston next rises, lubricating oil is released from the oil reservoir chamber 7A as shown in Figure 1. The oil is supplied to the outer circumference of the skirt portion 9 through the oil supply passage 10A, and is supplied to the cylinder 11. Lubricate the walls and the outer periphery of the skirt portion 9.

[0018] Also, when the piston rises, the oil ring that is closely supported on the lower surface of the oil ring groove 4 The lubricating oil scraped off from the cylinder wall by the groove 6 is placed on the bottom side of the oil ring groove 4. The oil flows into and accumulates in the high-rise oil reservoir chamber 7A, and the pressure ring 5 and oil ring 6 are Do not overflow into the space around the piston between the pistons.

[0019] Furthermore, even if the oil ring 6 is pushed into the bottom side of the oil ring groove 4, the oil The oil reservoir is supported by ring receivers 8 provided on both sides of the bottom of the ring groove 4. Since the oil does not enter the chamber 7A, the oil scraping effect of the oil ring 6 is impaired. Not possible.

[0020] In this embodiment, a hole-shaped oil reservoir is provided inside the piston body 1. 7A and an oil supply passage 10A have been described, but as shown in FIG. There is a slot opening in the center of the bottom of the oil ring groove 4 with a width narrower than that of the oil ring 6. A cut-shaped oil reservoir chamber 7B and this oil reservoir chamber 7B are connected to the piston body 1. The oil reservoir chamber 7B is formed to have the same length as the oil reservoir chamber 7B, which communicates with the outer periphery of the cart portion 9. The same effect can be obtained even if a slit-shaped oil supply passage 10B is provided. configured like this The vertical cross-sectional shape of the piston is similar to that shown in FIGS. 1 and 2.

[0021] Further, in another embodiment shown in FIG. 3, the length of the slit-shaped oil reservoir chamber 7B is adjusted. An example in which the piston body 1 is provided on the thrust side and anti-thrust side of the piston body 1 as in the previous embodiment. However, the oil reservoir chamber 7B and the oil supply passage 10B are completely connected to the piston body 1. It may be provided all around the circumference.

[0022]

[Effect of the idea]

As mentioned above, this idea is based on the radial side of the oil ring groove inside the piston body. The moisture scraped off by the oil ring when the piston descends is stored in the oil reservoir chamber provided in the A lubricating oil is stored inside the piston body when the piston rises. The oil is supplied to the outer periphery of the skirt part through the oil supply passage to the cylinder wall and the skirt part. Since the outer periphery of the piston can be lubricated, piston seizure can be reliably prevented.

[0023] In addition, the lubricating oil scraped off by the oil ring when the piston rises is removed from the oil reservoir. It accumulates in the oil chamber and overflows into the space around the piston between the pressure ring and the oil ring. Since lubricating oil can be reliably prevented from flowing into the combustion chamber, the amount of lubricating oil consumed can be reduced. Ru.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of this invention in a raised state.

FIG. 2 is a partial vertical sectional view showing an embodiment of the invention in a lowered state.

FIG. 3 is a side view showing another embodiment of the invention.

FIG. 4 is a partial longitudinal sectional view of a conventional piston for an internal combustion engine.

[Explanation of symbols]

1 Piston body 2 Crown part 4 Oil ring groove 6 Oil ring 7A Oil reservoir chamber 7B Oil storage room 9 Skirt part 10A oil supply passage 10B Oil supply passage

Claims (1)

[Scope of utility model registration request] Claim 1: An oil reservoir chamber that opens at the bottom of the oil ring groove is provided on the radial side of the oil ring groove inside the piston body, and an oil supply is provided in which the oil reservoir chamber is communicated with the outer periphery of the skirt portion. A piston for an internal combustion engine, characterized in that a passage is provided in the piston body.