Cylinder liner and internal combustion engine

Patent metadata

Field	Value
Publication number	US-12560130-B2
Application number	US-202218833031-A
Country	US
Kind code	B2
Filing date	Dec 2, 2022
Priority date	Jan 28, 2022
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

A cylinder liner ( 8 ) for an internal combustion engine ( 7 ), comprising a middle axis ( 9 ), and an inner surface ( 11 ) running around the middle axis ( 9 ). The inner surface ( 11 ) comprises a first zone ( 21 ), and a second zone ( 22 ), which differs from the first zone. The first zone ( 21 ) comprises a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm and a reduced groove depth Rvk of 1.5 to 2.5 μm. The second zone ( 22 ) comprises a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm and a reduced groove depth Rvk of 0.5 to 2.5 μm.

First claim

The invention claimed is:

1 . A cylinder liner for use in an internal combustion engine, the cylinder liner comprising:
a middle axis, and an inner surface running around the middle axis, wherein the inner surface comprises a first zone, which runs around the middle axis, and a second zone which runs around the middle axis, wherein the first zone and the second zone are arranged next to each other when viewed along the middle axis, wherein the first zone comprises a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm and a reduced groove depth Rvk of 1.5 to 2.5 μm, and wherein in the second zone the reduced peak height Rpk is less than 0.2 μm, the core roughness depth Rk is 0.05 to 0.35 μm and the reduced groove depth Rvk is 0.5 to 2.5 μm, wherein the first zone comprises a smallest material ratio Mr1 of less than 10% and a biggest material ratio Mr2 of 60 to 75%, wherein in the second zone the smallest material ratio Mr1 is less than 10% and the biggest material ratio Mr2 is 60 to 90%, wherein the inner surface further comprises a third zone which runs around the middle axis, wherein in the third zone the reduced peak height Rpk is less than 0.1 μm, the core roughness depth Rk is 0.05 to 0.2 μm and the reduced groove depth Rvk is 0.5 to 1.5 μm, wherein the second zone is arranged between the first zone and the third zone when viewed along the middle axis, wherein the cylinder liner is configured to receive a piston having a top dead point (OT) and a bottom dead point (UT) relative to the cylinder liner, wherein the first zone is positioned to include the top dead point (OT) and the third zone is positioned to include the bottom dead point (UT), wherein a ratio of a first height of the first zone to a total height of the inner surface of the cylinder liner is 0.02 to 0.065, wherein a ratio of a second height of the second zone to the total height of the cylinder liner is 0.06 to 0.1, wherein a ratio of a third height of the third zone to the total height of the cylinder liner is 0.7 to 0.9.

2 . The cylinder liner according to claim 1 , wherein in the third zone the smallest material ratio Mr1 is less than 10% and a biggest material ratio Mr2 is 65 to 90%.

3 . The cylinder liner according to claim 1 , wherein
a ratio of the first height of the first zone to the second height of the second zone is 0.25 to 0.75.

4 . The cylinder liner according to claim 1 , wherein
a ratio of the first height of the first zone to the third height of the third zone is 0.02 to 0.08.

5 . The cylinder liner according to claim 1 , wherein
a ratio of the second height of the second zone to the third height of the third zone is 0.07 to 0.11.

6 . The cylinder liner according to claim 1 , wherein
the inner surface of the cylinder liner is machined by a honing process, wherein a hone angle is 30 to 60°.

7 . The cylinder liner according to claim 1 , wherein the cylinder liner further comprises:
a basic section having the inner surface, and a collar section adjoining the basic section and having an inner surface of the collar radially offset outwardly from the inner surface of the cylinder liner in a radial direction; and a shoulder defined by the basic section and the collar section, wherein the first zone is adjacent to the shoulder.

8 . An internal combustion engine comprising at least one cylinder liner according to claim 1 configured to receive the piston which is guided on the inner surface of the cylinder liner during operation of the internal combustion engine.

9 . The cylinder liner of claim 1 , wherein
the ratio of the first height of the first zone to the total height of the inner surface of the cylinder liner is 0.04, the ratio of the second height of the second zone to the total height of the inner surface of the cylinder liner is 0.08, and the ratio of the third height of the third zone to the total height of the inner surface of the cylinder liner is 0.9.

10 . The cylinder liner of claim 1 , wherein
a ratio of the first height of the first zone to the second height of the second zone is 0.25 to 0.75; a ratio of the first height of the first zone to the third height of the third zone is 0.02 to 0.08; and a ratio of the second height of the second zone to the third height of the third zone is 0.07 to 0.11.

11 . A cylinder liner for use in an internal combustion engine, the cylinder liner comprising:
a middle axis, and an inner surface running around the middle axis, the inner surface comprising: a first zone, which runs around the middle axis, wherein the first zone includes a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm, and a reduced groove depth Rvk of 1.5 to 2.5 μm; a second zone which runs around the middle axis, wherein the second zone includes a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm and a reduced groove depth Rvk of 0.5 to 2.5 μm; and a third zone which runs around the middle axis, wherein the third zone includes a reduced peak height Rpk of less than 0.1 μm, a core roughness depth Rk of 0.05 to 0.2 μm, and a reduced groove depth Rvk of 0.5 to 1.5 μm, wherein the second zone is positioned between the first zone and the third zone when viewed along the middle axis, wherein the reduced groove depth Rvk of the first zone is greater than the reduced groove depth Rvk of the second zone, and the reduced groove depth Rvk of the second zone is greater than the reduced groove depth Rvk of the third zone.

12 . The cylinder liner of claim 11 , wherein the first zone includes a first height, the second zone includes a second height, and the third zone includes a third height, wherein the third height of the third zone is greater than the second height of the second zone, and the second height of the second zone is greater than the first height of the first zone.

13 . The cylinder liner of claim 12 , wherein
a ratio of the first height of the first zone to the third height of the third zone is 0.02 to 0.08; and a ratio of the second height of the second zone to the third height of the third zone is 0.07 to 0.11.

Assignees

• Ks Kolbenschmidt Gmbh

Inventors

• Hanke Wolfgang

Classifications

• F02F1/004 Primary

  Cylinder liners (F02F1/08, F02F1/16 take precedence) · CPC title

• F02F1/18 Primary

  Other cylinders · CPC title