Piston ring

Inactive Publication Date: 2012-08-16
NIPPON PISTONRING CO LTD
View PDF9 Cites 31 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0025]According to the present invention, in the piston ring provided at its outer periphery with the sliding surface, the sliding surface includes the first sliding surface which is formed of hard film and the second sliding surface which is not formed of hard film. Therefore, the first sliding surface can give “wear resistance” to the piston ring, and the second sliding surface can secure “gas sealing performance and oil scraping performance”. Further, since the second sliding surface exists at the position deviated inward from the phantom line extending from the first sliding surface toward the other end. Hence, it is possible to prevent the two sliding surfaces having different hardness from coming into contact with an inner peripheral surface of the cylinder at the same time. Therefore, it is possible to prevent a scratch or a scuff from being generated on the second sliding surface having lower hardness than that of the first sliding surface. This configuration prevents the inner peripheral surface of the cylinder which is a mating member from being damaged or worn, and prevents the piston ring itself from being abnormally worn.
[0026]The outer peripheral surface of the base material of the piston ring which is the recess on which the hard film is formed is formed into the predetermined shape. According to this, a boundary portion betwe

Problems solved by technology

According to this, since the hard film formed on the sliding surface is “hard”, the film

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Piston ring
  • Piston ring
  • Piston ring

Examples

Experimental program
Comparison scheme
Effect test

examples

[0083]The piston ring of the present invention will be described in more concretely using Examples.

examples 1 to 12

[0084]The piston ring (oil ring) shown in FIGS. 1 was produced using the method explained using FIGS. 2A to 2E.

[0085]Here, SUS440B expressed in JIS was used as the base material (2).

[0086]The hard films (3) were Cr—B—N (Examples 1 to 6) and Cr—N (Examples 7 to 12) formed by the ion plating method.

[0087]Sizes of the produced piston ring were as follows: a diameter was 115 mm, a width (h1) in the axial direction was 3.0 mm, and a width (a1) in the radial direction was 3.95 mm. A length (n) of the base material exposed from a lower portion (edge portion) of an outer peripheral sliding surface of the piston ring was 0.2 to 0.5 mm.

[0088]In the Examples 1 to 12, a value of an angle (a) formed between the piston ring outer peripheral surface (Z) and the second surface (Y) which configures the recess (21) formed in the base material (2) is as shown in Table 1. The piston ring was cut so that a cross section thereof in its axial direction could be observed, the cross section was polished and...

examples 1 to 2

Conventional Examples 1 to 2

[0091]Conventional examples in which hard films (3) were formed on the entire outer peripheral surfaces of the base materials (2) were produced in the same manner as those of the Examples. Details thereof are as shown in Table 1.

[0092]

[0093]A twist test was carried out using a twist peel test machine 40 shown in FIG. 5.

[0094]In the twist test, opposed mating ends of a gap 5 of the piston ring 1 are held by holding tools 41a and 41b, the holding tool 41a is fixed, the holding tool 41b is rotated around an opposite side 6 of the gap in a radial direction of the piston ring 1 as shown with dashed lines, and the piston ring 1 is twisted at a predetermined twisting angle. The twisting angle was 90°. After the piston ring 1 was twisted, the opposite side 6 which was opposite from the gap of the piston ring 1 was cut, and it was visually observed whether a film layer in the cut surface (fracture) was peeled off from a ring base material. As a result of the obser...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Angleaaaaaaaaaa
Angleaaaaaaaaaa
Shapeaaaaaaaaaa
Login to view more

Abstract

A piston ring is provided at its outer periphery with a sliding surface, wherein in a cross section thereof which is perpendicular to a radial direction of the piston ring, the sliding surface includes a first sliding surface which occupies a predetermined region from one end thereof, and a second sliding surface which occupies a region extending from one end to the other end of the first sliding surface, the first sliding surface is formed of hard film, the second sliding surface is not formed of hard film, and the second sliding surface exists at a position deviated inward from a phantom line extending from the first sliding surface toward the other end.

Description

TECHNICAL FIELD[0001]The present invention relates to a piston ring used in an internal combustion engine.BACKGROUND ART[0002]Generally, a pressure ring and an oil ring are attached to a piston for an internal combustion engine as piston rings. The pressure ring is provided with a function of preventing a phenomenon (blow-by) in which high pressure combustion gas flows from a combustion chamber toward a crankcase. On the other hand, the oil ring is mainly provided with a function of suppressing a phenomenon (oil loss via the piston ring) in which redundant lubricant on a cylinder inner wall enters a combustion chamber from a crankcase and is consumed. As a combination of conventionally standard piston rings, there is known a combination of three piston rings, i.e., one oil ring and two compression rings including a top ring and a second ring.[0003]In recent years, with reduction tendency in weight and increase tendency in output of the internal combustion engine, quality required fo...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): F16J9/26
CPCF16J9/20C23C14/0641F16J9/26F16J9/206B23P15/06B23P15/065
Inventor FUJIMURA, KAZUHIROCHIBA, ATSUSHIAKIMOTO, NAOYUKIHIRAISHI, IWAO
Owner NIPPON PISTONRING CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap