Internal Combustion Engine Lubricated With a Water-Containing Lubricant

Abstract

An internal combustion engine includes an internal combustion engine interior and a lubricant disposed in the internal combustion engine interior. The lubricant lubricates a component disposed in the internal combustion engine interior and the lubricant is a water-containing lubricant. In an embodiment, the internal combustion engine interior is fluidically connected to an environment surrounding the internal combustion engine by a ventilation device where the ventilation device has a semipermeable membrane which is impermeable to water and water vapor.

Claims

1.-8. (canceled)

9. An internal combustion engine, comprising: an internal combustion engine interior; and a lubricant, wherein the lubricant is disposed in the internal combustion engine interior, wherein the lubricant lubricates a component disposed in the internal combustion engine interior, and wherein the lubricant is a water-containing lubricant.

10. The internal combustion engine according to claim 9 further comprising a water injection device, wherein water is introducible into a combustion chamber of the internal combustion engine by the water injection device.

11. The internal combustion engine according to claim 10, wherein water is feedable from the water injection device to the water-containing lubricant.

12. The internal combustion engine according to claim 9 further comprising a ventilation device, wherein the internal combustion engine interior is fluidically connected to an environment surrounding the internal combustion engine by the ventilation device; wherein the ventilation device has a first semipermeable membrane which is impermeable to water and water vapor in a first direction from a first surface of the first semipermeable membrane toward a second surface of the first semipermeable membrane and wherein the first surface of the first semipermeable membrane faces toward the internal combustion engine interior.

13. The internal combustion engine according to claim 12, wherein the ventilation device has a second semipermeable membrane, wherein the second semipermeable membrane is disposed downstream of the first semipermeable membrane in relation to a first flow direction from the internal combustion engine interior to the environment surrounding the internal combustion engine, and wherein the second semipermeable membrane is impermeable to water and water vapor in a second flow direction from the environment surrounding the internal combustion engine to the internal combustion engine interior.

14. The internal combustion engine according to claim 9, wherein the internal combustion engine is a reciprocating-piston internal combustion engine and wherein the component disposed in the internal combustion engine interior is a crankshaft.

15. The internal combustion engine according to claim 9 further comprising a timing drive with a camshaft, wherein the camshaft has a friction-reducing coating at least in a section.

16. The internal combustion engine according to claim 9 in combination with a crankshaft starter generator, wherein the crankshaft starter generator and the internal combustion engine are supplied with the water-containing lubricant.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0019] FIG. 1 is a schematic cross section through an internal combustion engine with water-containing lubricant and ventilation means.

DETAILED DESCRIPTION OF THE DRAWING

[0020] FIG. 1 illustrates a schematic cross section through an internal combustion engine 1. In the internal combustion engine 1, the crankshaft 12 and connecting rod 10 and piston 11, and corresponding bearings and bearing points, are arranged as components to be lubricated. For the lubrication of these components, the water-containing lubricant 3 is accommodated in the internal combustion engine interior 2. For ventilation, the internal combustion engine 1 has a ventilation means 5 (ventilation device) with a semipermeable membrane 8. For the control of the gas exchange, the internal combustion engine 1 has the cylinder head 4. Arranged in the cylinder head 4 is the camshaft, which can be driven by the timing drive (not illustrated) and by means of which the gas exchange in the internal combustion engine 1 can be controlled by way of so-called inlet and outlet valves.

[0021] Here, the semipermeable membrane 8 is arranged so as to be impermeable to water and/or water vapor in a flow direction 6 from the internal combustion engine interior 2 into the environment 9 surrounding the internal combustion engine 1. Furthermore, the semipermeable membrane 8 is permeable to water and/or water vapor with respect to a flow direction 7 from the environment 9 surrounding the internal combustion engine 1 into the internal combustion engine interior 2.

[0022] By means of such a configuration of the internal combustion engine 1, it is made possible that no or only small quantities of moisture (water/water vapor) can escape from the internal combustion engine 1 and the water content in the water-containing lubricant 3 in the internal combustion engine interior 2 is thus, in particular during the operation thereof, kept at least substantially constant.

[0023] In other words, the invention provides the use of a water-containing lubricant for lubrication and/or cooling in an internal combustion engine. Through this use,

[0024] a lowering of viscosity in relation to conventional lubricating oils, that is to say in particular non-water-containing lubricants, is made possible and a reduction in the power losses/drag losses can be achieved in this way;

[0025] a reduction in the lubricating oil volume can be achieved through improved calorific properties of the water-containing lubricant in relation to conventional lubricating oil (heat transfer, heat capacity);

[0026] synergistic effects with the cooling water circuit (cooling power, potential for use of only one medium) are made possible, and thus a simplification/a replacement of the so-called cooling water circuit can be achieved;

[0027] and, through the use of coated friction partners/components (inter alia DLC on piston and cylinder), a friction reduction can be achieved and, in particular with the use of coated friction partners, there is resulting potential for generation of superlubricity.

LIST OF REFERENCE CHARACTERS

[0028] 1 Internal combustion engine [0029] 2 Internal combustion engine interior [0030] 3 Water-containing lubricant [0031] 4 Cylinder head [0032] 5 Ventilation means [0033] 6 Flow direction out of the internal combustion engine [0034] 7 Flow direction into the internal combustion engine [0035] 8 Semipermeable membrane [0036] 9 Environment [0037] 10 Connecting rod with bearings [0038] 11 Piston [0039] 12 Crankshaft with bearings [0040] 13 Combustion chamber