Device and method for lubricating a connecting rod bearing

Patent metadata

Field	Value
Publication number	US-11359525-B2
Application number	US-201816213726-A
Country	US
Kind code	B2
Filing date	Dec 7, 2018
Priority date	Dec 20, 2017
Publication date	Jun 14, 2022
Grant date	Jun 14, 2022

Abstract

A device lubricates a connecting rod bearing on a crankshaft of an internal combustion engine. The device has a piston having an internal piston cooling fluid channel, and an outlet channel in fluid communication with the fluid channel. The device has a connecting rod, which is connected to the piston in an articulated, in particular pivotable, manner, and has a large connecting rod eye and a connecting channel. The large connecting rod eye is formed for receiving the connecting rod bearing. The connecting channel forms a fluid connection between the outlet channel and the large connecting rod eye so that a fluid, in particular a cooling lubricating fluid (e.g. oil), can be fed, or is fed, from the fluid channel to the large connecting rod eye via the outlet channel and the connecting channel. The connecting rod bearing can be lubricated by cooling oil from the fluid channel of the piston.

First claim

The invention claimed is:

1. A device for lubricating a connecting rod bearing on a crankshaft of an internal combustion engine, comprising:
a piston having a fluid channel comprising an internal piston cooling fluid channel, and an outlet channel in fluid communication with the fluid channel;
a connecting rod connected to the piston in a pivotable manner, the connecting rod having a large connecting rod eye and a connecting channel,

wherein:
the large connecting rod eye is configured to receive the connecting rod bearing; and
the connecting channel forms a direct fluid connection between the outlet channel and the large connecting rod eye such that a fluid in the form of a cooling lubricating fluid is fed from the fluid channel to the large connecting rod eye and the connecting rod bearing via the outlet channel and the connecting channel.

2. The device according to claim 1 , wherein:
the outlet channel has an outlet opening in a rounded piston head of the piston; and/or
the connecting channel has an inlet opening in a rounded, outer circumferential surface of a small end of the connecting rod.

3. The device according to claim 1 , wherein:
the connecting channel has an inlet region formed by a step-shaped recess in an outer circumferential surface of a small end of the connecting rod.

4. The device according to claim 3 , wherein the connecting channel further comprises:
a slant bore extending from the recess and, at a spacing from a small connecting rod eye of the connecting rod, through the small end to a connecting rod shaft of the connecting rod; and
a longitudinal bore extending from the large connecting rod eye through the connecting rod shaft to the slant bore.

5. The device according to claim 1 , wherein:
a small end of the connecting rod and a piston head of the piston are configured such that a spacing between a region of the piston head which adjoins an outlet opening of the outlet channel and a region of the small end which adjoins an inlet opening of the connecting channel is smaller than 0.1 cm.

6. The device according to claim 5 , wherein:
the region of the piston head and the region of the small end sweep over one another during a pivotal movement between the piston and the connecting rod.

7. The device according to claim 1 , wherein:
a small end of the connecting rod and a piston head of the piston are configured such that a spacing between a region of the piston head which adjoins an outlet opening of the outlet channel and a region of the small end which adjoins an inlet opening of the connecting channel is smaller than 0.01 cm.

8. The device according to claim 7 , wherein:
the region of the piston head and the region of the small end sweep over one another during a pivotal movement between the piston and the connecting rod.

9. The device according to claim 1 , wherein:
a piston head of the piston covers an inlet opening of the connecting channel during a movement of the piston from an upper dead center to a lower dead center, in particular for reducing the cavitation tendency in the connecting channel; and/or
an outlet opening of the outlet channel overlaps an inlet opening of the connecting channel during a movement of the piston from a lower dead centre to an upper dead centre.

10. The device according to claim 1 , wherein:
a piston head of the piston covers an inlet opening of the connecting channel within an angular range which is smaller than a predetermined angular range within which the connecting rod is pivotably connected to the piston; and/or
an outlet opening of the outlet channel overlaps an inlet opening of the connecting channel within an angular range which is smaller than a predetermined angular range within which the connecting rod is pivotably connected to the piston.

11. The device according to claim 1 , wherein:
a fluid connection between the outlet channel and the connecting channel is an intermittent fluid connection and/or exists substantially only during a movement of the piston from a lower dead center to an upper dead center.

12. The device according to claim 1 , wherein:
the connecting channel bypasses a small connecting rod eye of the connecting rod and/or a piston pin which connects the connecting rod pivotably to the piston.

13. The device according to claim 1 , wherein:
a small end of the connecting rod includes an increased wall thickness in a region through which the connecting channel extends; and/or
the piston includes an increased wall thickness in a region through which the outlet channel extends.

14. The device according to claim 1 , further comprising:
a fluid injecting nozzle directed towards an inlet opening of an inlet channel of the piston, the fluid injecting nozzle in fluid communication with the fluid channel.

15. The device according to claim 14 , wherein:
the fluid injecting nozzle is provided separately from the piston and from the connecting rod; and/or
the fluid injecting nozzle is received by or secured on a crankcase.

16. A motor vehicle, in particular a commercial vehicle, comprising a device for lubricating a connecting rod bearing on a crankshaft of an internal combustion engine, the device comprising:
a piston having a fluid channel comprising an internal piston cooling fluid channel, and an outlet channel in fluid communication with the fluid channel;
a connecting rod connected to the piston in an articulated, in particular pivotable, manner, the connecting rod having a large connecting rod eye and a connecting channel,

wherein:
the large connecting rod eye is configured to receive the connecting rod bearing; and
the connecting channel forms a direct fluid connection between the outlet channel and the large connecting rod eye such that a fluid in the form of a cooling lubricating fluid is fed from the fluid channel to the large connecting rod eye and the connecting rod bearing via the outlet channel and the connecting channel.

17. A method for lubricating a connecting rod bearing on a crankshaft, comprising:
feeding a cooling lubricating fluid from an internal cooling fluid channel of a piston to the connecting rod bearing via a connecting channel of a connecting rod, the connecting channel forming a direct fluid connection between an outlet channel of the piston, which is in fluid connection with the internal cooling fluid channel, and a large connecting rod eye of the connecting rod, in which the connecting rod bearing is received.

Assignees

• Man Truck & Bus Ag

Inventors

• Malischewski Thomas
• Dietrich Jens
• Hirschmann Steffen
• Renner Dominik

Classifications

• F01M2011/027

  for lubricating connecting rod bearings · CPC title

• F01M1/06 Primary

  Lubricating systems characterised by the provision therein of crankshafts or connecting rods with lubricant passageways, e.g. bores (crankshafts, connecting-rods, per se F16C) · CPC title

• F16J1/09

  with means for guiding fluids (F16J1/08 takes precedence) · CPC title

• F16C37/007

  of rolling bearings · CPC title

• F16C7/023

  for piston engines, pumps or the like · CPC title