RU2440503C2 - Cylinder-and-piston group - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: cylinder-and-piston group includes a sleeve and piston with piston rings. Grooves are made on working surface of sleeve in opposite direction. Grooves are filled with non-ferrous metal. Grooves are made in the form of closed rings separated from each other. Angle of elevation of the first and the last grooves is in the range of 15…20 degrees, central groove - 40…45 degrees to diametrical plane of the sleeve. Grooves are located on working surface of sleeve from upper dead point to lower dead point.

EFFECT: improving operating quality of cylinder-and-piston group; decreasing friction coefficient between working surfaces of piston rings and sleeve.

2 dwg

Description

The invention relates to mechanical engineering, in particular to a cylinder-piston group of internal combustion engines (ICE).

Known cylinder-piston group [1], comprising a piston with rings placed on it, which are in contact with the working surface of the liner. On the inner surface of the sleeve grooves are made, consisting of two counter helical lines with right and left threads, respectively. The helical lines of the grooves are filled with non-ferrous metal, the angle of their rise lies within 15 ... 60 degrees, and the step size does not exceed the distance between the upper compression and lower oil scraper rings.

However, the known device has a disadvantage, which can be attributed to the unsatisfactory quality of the cylinder-piston group due to the uneven distribution of non-ferrous metal on the working surface of the cylinder liner due to the uneven depth of cut of the helical grooves.

The purpose of the invention is improving the quality of work of the cylinder-piston group.

This goal is achieved by the fact that the grooves are made in the form of closed rings, separate from each other. The elevation angle of the first and last grooves is within 15 ... 20 degrees, the central groove is 40 ... 45 degrees to the diametrical plane of the sleeve. The grooves in the longitudinal section are mountainous, and the grooves are located on the working surface of the liner from top dead center to bottom dead center.

In Fig.1 shows a cylinder liner with grooves made on its working surface, Fig.2 is a diagram of the contact of the piston rings with the working surface of the liner.

The cylinder-piston group contains a sleeve 1, a piston 2, a compression 3 and an oil scraper 4 piston rings. On the working surface of the sleeve 1 grooves 5 and 6 are made with variable lifting angles. The elevation angle φ of the first and last grooves 5 is made within 15 ... 20 degrees, and the central groove 6 is 40 ... 45 degrees to the diametrical plane of the sleeve. Grooves 5 and 6 are made in the form of closed rings, separate from each other. The grooves 5 and 6 are filled with non-ferrous metal 7, for example, copper. The grooves 5 and 6 in longitudinal section have a toroidal shape. Grooves 5 and 6 are located on the working surface of the sleeve 1 from top dead center to bottom dead center.

The cylinder-piston group operates as follows. During operation of the internal combustion engine (ICE), the piston 2 with rings 3 and 4 performs a reciprocating movement up and down. In this case, rings 3 and 4, moving along the working surface of the sleeve 1, with plastic deformation remove part of the non-ferrous metal 7 from grooves 5 and 6 and “smear” it along the working surface of the sleeve 1 from top dead center (TDC) to bottom dead center (BDC) . This process occurs during all engine cycles (ICE) and continues until a non-ferrous metal layer 7 of a certain thickness is formed on the working surface of the sleeve 1. As a result of this process, the coefficient of friction of the working surfaces of the piston rings 3 and 4 and the working surface of the sleeve 1 decreases, and the rings 3 and 4 cease to remove the non-ferrous metal 7 from the grooves 5 and 6. As the thickness of the “smeared” non-ferrous metal 7 decreases from the surface of the sleeve 1 the friction coefficient between the working surfaces of the piston rings 3 and 4 and the working surface of the sleeve 1 increases slightly. At the same time, the intensity of removing the non-ferrous metal 7 from the grooves 5 and 6 by the piston rings 3 and 4 begins to increase, and the process of “smearing” the non-ferrous metal 7 along the working surface of the sleeve 1 is repeated.

Thus, the process of applying a layer of non-ferrous metal 7 on the working surface of the sleeve 1 accompanies the entire period of operation of the cylinder-piston ICE group.

Performing the angle of elevation of the grooves located on the working surface of the sleeve from top dead center to bottom dead center, within 15 ... 45 degrees to the diametrical plane of the sleeve and filled with non-ferrous metal (copper), will contribute to the formation of a protective film on the working surface of the sleeve, due to the return - progressive movement of the piston in the cylinder liner, and a decrease in the coefficient of friction of the piston rings against the wall of the cylinder liner.

In addition, the implementation of the grooves in the form of separate closed rings contributes to the accuracy of the depth of their cutting, and, accordingly, increases the uniformity of filling the grooves with non-ferrous metal (copper).

Information sources:

1. Cylinder-piston group. Patent RU No. 2186234. Publ. 07/27/2002

Claims (1)

A cylinder-piston group comprising a sleeve, a piston with piston rings, grooves are made on the working surface of the sleeve, the grooves being filled with non-ferrous metal, characterized in that the grooves are made in the form of closed rings separate from each other, the elevation angle of the first and last grooves is made within 15 ... 20 °, the central groove - 40 ... 45 ° to the diametrical plane of the liner, and the grooves are located on the working surface of the liner from top dead center to bottom dead center.

Images