METHOD FOR COATING THE SURFACE OF A CLOSED COOLING CHANNEL OF A PISTON FOR AN INTERNAL COMBUSTION ENGINE AND PISTON PRODUCED BY SAID METHOD

Ulrich Bischofberger

Patent

Atlas literature

Patent

US 10,252,293

METHOD FOR COATING THE SURFACE OF A CLOSED COOLING CHANNEL OF A PISTON FOR AN INTERNAL COMBUSTION ENGINE AND PISTON PRODUCED BY SAID METHOD

Ulrich Bischofberger

Claims

Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.

4 independent · 18 dependent

1
Independenth-BNpolysiloxanehexagonal boron nitride coatingpiston with coated closed cooling channel
A method for coating a surface of a closed cooling channel, having a plurality of oil supply bores and a plurality of oil discharge bores, of a piston for an internal combustion engine, comprising: a) introducing a deﬁned quantity of[[the]] _ a coating medium including a suspension of hexagonal boron nitride with a solution including at least one thermally curable inorganic binder and at least one solvent into the cooling channel; b) spreading the coating medium over the surface of the cooling channel by moving the piston about at least two spatial axes; c) using a laminar air ﬂow to dry the coating medium spread over the surface of the cooling channel; and d) thermally curing the coating medium to complete a coating adhering to the surface of the cooling channel. Currently amended
1. 2
  Dependent← claim 1
  The method as claimed in claim 1, wherein prior to step a) a size of the surface of the cooling channel is determined. Previously presented
2. 3
  Dependent← claim 1
  The method as claimed in claim 1, wherein prior to step a) the surface of the cooling channel is cleaned with a cleaning substance. Previously presented
3. 5
  Dependent← claim 1polysiloxane
  The method as claimed in claim 1, wherein in step a) at least one polysiloxane is used as the at least one thermally curable inorganic binder. Previously presented
4. 7
  Dependent← claim 1Na₂SiO₃K₂SiO₃
  The method as claimed in claim 1, wherein at least one of sodium silicate and potassium silicate is used as an additional binder. Previously presented
5. 8
  Dependent← claim 1hexagonal boron nitride coating
  The method as claimed in claim 1, wherein in step a) a quantity of 7 ml of the coating medium is used to coat the surface of the cooling channel[[of]] per 190 cm 2 of area. Currently amended
6. 9
  Dependent← claim 1
  The method as claimed in claim 1, wherein in step b) the piston is moved via a biaxial mixing device. Previously presented
7. 10
  Dependent← claim 1
  The method as claimed in claim 1, wherein in step c) the laminar air ﬂow has a velocity of 1 to 2 meters per second. Previously presented
8. 11
  Dependent← claim 1
  The method as claimed in claim 1, wherein in step c) drying is carried out at room temperature. Previously presented
9. 12
  Dependent← claim 1
  The method as claimed in claim 1, wherein in step d) the thermal curing is carried out at a temperature of 180 ° C to 220 °C. Previously presented
10. 16
  Dependent← claim 1hexagonal boron nitride coating
  The method as claimed in claim 1, wherein the coating has a substantially uniform thickness over an entire surface of the cooling channel. Currently amended
11. 17
  Dependent← claim 1hexagonal boron nitride coating
  The method as claimed in claim 1, wherein the coating has a thickness of between 10 p m and 100 pm. Previously presented
12. 18
  Dependent← claim 1hexagonal boron nitride coating
  The method as claimed in claim 1, wherein a thickness of the coating is between 20 p m to pm. Previously presented
13. 19
  Dependent← claim 1hexagonal boron nitride coating
  The method as claimed in claim 1, wherein a thermal conductivity of the coating is 40 W/mK to 50 W/mK. Previously presented
14. 20
  Dependent← claim 1hexagonal boron nitride coating
  The method as claimed in claim 1, wherein a coeﬃcient of friction of the coating is 0.2 and is constant up to a temperature of 600 °C. Previously presented
15. 22
  Dependent← claim 1
  The method as claimed in claim 1, wherein a 2/g. Previously presented
16. 23
  Dependent← claim 1hexagonal boron nitride coatingpiston with coated closed cooling channel
  The method as claimed in claim 1, wherein surface area of the coating is 5 m 2/g to 15 m the piston comprises steel. Previously presented
13
Independent
- 15. Canceled
15
Independent
Canceled
21
Independent
Canceled

Worked examples

Embodiments described in the patent, grouped by the materials and process steps they use.

Exemplary embodiment of coating method

description derived process summary

5 materials3 process steps

The surface area of the cooling channel (190 cm2) is determined. The surface is cleaned with 10–30 ml ethanol introduced via a bore, spread by piston motion with a biaxial mixer, and dried via laminar air flow (1–2 m/s, room temperature, 5 min). A coating medium (suspension of hexagonal boron nitride in polysiloxane dissolved in ethanol; hBN content 104 g/l based on pure polysiloxane solution volume; polysiloxane content 61 g/l based on total suspension volume; ethanol content 647 g/l based on total suspension volume; commercial product HeBoCoat 400E, Henze Boron Nitride Products AG) is introduced (7 ml for 190 cm2 surface; 4.53 g ethanol, 0.43 g polysiloxane, 0.73 g hBN). Bores are plugged; piston moved biaxially to spread medium evenly. Plugs removed; medium dried with laminar air flow (1–2 m/s, ~20 °C, ~5 min). Curing by heat treatment at 180–220 °C for 25–60 min converts polysiloxane to SiO₂ matrix embedding hBN particles. Resulting coating: surface energy 15–17 mN/m, layer thickness 20–40 µm, uniform over entire cooling channel surface.

Device structures

Layer stacks claimed or described, ordered top of device to substrate.

piston with coated closed cooling channel

hexagonal boron nitride coatinghBN coating

substrate_piston_bodysubstrate piston body

Materials

Materials described outside the worked examples.

methanol

CH₃OH

Cleaning Substance

acetone

(CH₃)2CO

Cleaning Substance

Reported properties

Performance values and ranges asserted in the specification or claims.

Property	Value	Material
Coating Thickness	10–100 µm	hexagonal boron nitride coating
Coating Thickness	20–40 µm

Why these are connected

Related documents with shared materials, methods, properties, or citations.

METHOD FOR COATING THE SURFACE OF A CLOSED COOLING CHANNEL OF A PISTON FOR AN INTERNAL COMBUSTION ENGINE AND PISTON PRODUCED BY SAID METHOD | Matter42 Literature