# US 11,112,009 B2 · Low heat transfer piston via binder jet technology

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,112,009 B2
- Document ID: US11112009B2
- Status: Granted
- Kind: B2
- Application number: 16/839,626
- Filed: 2020-04-03
- Published: 2020-10-15
- Granted: 2021-09-07
- Earliest claimed: 2019-04-10
- Assignees: Cummins Inc.
- Applicants: Cummins Inc.
- Inventors: David M. Barnes
- Web page: https://patentgrep.com/patent/US11112009B2

## CPC

- F16J 1/008: {with sealing lips}
- B22F 5/008: {of engine cylinder parts or of piston parts other than piston rings (of piston rings B22F5/02)}
- B22F 7/08: with one or more parts not made from powder {(B22F7/062 takes precedence)}
- B23P 15/10: pistons
- B33Y 10/00: Processes of additive manufacturing
- B33Y 40/20: Post-treatment, e.g. curing, coating or polishing
- F02F 3/003: {the parts being connected by casting, brazing, welding or clamping}
- F16J 1/001: {One-piece pistons}
- F16J 1/01: characterised by the use of particular materials (F16J1/02 takes precedence)
- F16J 1/09: with means for guiding fluids (F16J1/08 takes precedence)
- B22F 10/14: by jetting of binder onto a bed of metal powder
- B22F 10/25: Direct deposition of metal particles, e.g. direct metal deposition [DMD] or laser engineered net shaping [LENS]
- B22F 10/28: Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
- B22F 2998/10: Processes characterised by the sequence of their steps
- B33Y 80/00: Products made by additive manufacturing
- Y02P 10/25: Process efficiency
- F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS
- B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B23P: METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS (arrangements for copying or controlling B23Q)
- B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- F02F: CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

A piston for an internal combustion engine includes a skirt and a crown coupled to the skirt. The crown is produced in isolation from the skirt using an additive manufacturing process. The piston includes a first air gap between the crown and the skirt. According to an example embodiment, the crown includes a plurality of sections produced in isolation from the skirt. The crown may include a second air gap disposed between two of the plurality of sections.

## Claims

### Claim 1

A piston, comprising:
a skirt; and
a crown sintered to the skirt, the crown produced in isolation from the skirt using an additive manufacturing process, the piston including a first air gap between the crown and the skirt.

### Claim 2 (depends on 1)

The piston of claim 1, wherein at least one of the crown and the skirt comprises a recessed area, the recessed area disposed between the skirt and the crown so as to form the first air gap.

### Claim 3 (depends on 1)

The piston of claim 1, wherein the crown comprises a plurality of sections produced in isolation from the skirt using the additive manufacturing process, the crown including a second air gap disposed between two of the plurality of sections such that the piston includes a plurality of air gaps.

### Claim 4 (depends on 3)

The piston of claim 3, wherein each one of the plurality of air gaps comprises a plurality of air pockets distributed in a row between either (i) two sections of the plurality of sections; or (ii) the crown and the skirt, and wherein a total number of air gaps is equal to a total number of sections.

### Claim 5 (depends on 1)

The piston of claim 1, wherein the skirt comprises an upper portion and a lower portion extending downwardly from the upper portion, the lower portion defining a cylindrical tube, wherein the upper portion includes an upper wall that extends across a first end of the cylindrical tube and covers the first end, and wherein the crown is coupled to the upper wall.

### Claim 6 (depends on 1)

The piston of claim 1, wherein at least one of the crown or the skirt comprises an isogrid, the isogrid comprising a plurality of ribs defining a plurality of recessed areas, the plurality of recessed areas forming a portion of the first air gap.

### Claim 7 (depends on 6)

The piston of claim 6, wherein the crown comprises a plurality of sections including a middle section, wherein the middle section includes a middle upper isogrid disposed on an upper surface of the middle section and a middle lower isogrid disposed on a lower surface of the middle section, and wherein an outer diameter of the middle upper isogrid is greater than an outer diameter of the middle lower isogrid.

### Claim 8 (depends on 1)

The piston of claim 1, wherein at least one of the crown or the skirt includes an oil port that fluidly couples the first air gap to a lower portion of the skirt.

### Claim 9

An internal combustion engine, comprising:
a cylinder block defining a cavity;
a cylinder head coupled to an upper end of the cylinder block and covering the cavity;
a piston at least partially disposed within the cavity, the piston comprising:
a skirt; and
a crown sintered to the skirt, the crown produced in isolation from the skirt using an additive manufacturing process, the piston including a first air gap between the crown and the skirt.

### Claim 10 (depends on 9)

The internal combustion engine of claim 9, wherein at least one of the skirt or the crown comprises a recessed area, and wherein the recessed area is disposed between the skirt and the crown so as to form the first air gap.

### Claim 11 (depends on 9)

The internal combustion engine of claim 9, wherein the crown comprises a plurality of sections produced in isolation from the skirt using the additive manufacturing process, the crown including a second air gap disposed between two of the plurality of sections such that the piston includes a plurality of air gaps.

### Claim 12 (depends on 9)

The internal combustion engine of claim 9, wherein the skirt comprises an upper portion and a lower portion extending downwardly from the upper portion, wherein the lower portion defines a cylindrical tube, wherein the upper portion includes an upper wall that extends across a first end of the cylindrical tube and covers the first end, and wherein the crown is coupled to the upper wall.

### Claim 13 (depends on 9)

The internal combustion engine of claim 9, wherein at least one of the crown or the skirt comprises an isogrid, wherein the isogrid comprises a plurality of ribs defining a plurality of recessed areas, and wherein the plurality of recessed areas form a portion of the first air gap.

### Claim 14 (depends on 9)

The internal combustion engine of claim 9, further comprising a crankcase coupled to the cylinder block, wherein the piston includes an oil port that fluidly couples the first air gap to the crankcase.

### Claim 15

A method, comprising:
forming a skirt using an additive manufacturing process;
forming a crown in isolation from the skirt using the additive manufacturing process, at least one of the skirt or the crown comprising a recessed area;
positioning crown onto the skirt such that the recessed area is disposed therebetween; and
sintering the crown to the skirt.

### Claim 16 (depends on 15)

The method of claim 15, wherein the recessed area is one of a plurality of recessed areas, and wherein at least one of the skirt or the crown comprises a plurality of ribs defining the plurality of recessed areas.

### Claim 17 (depends on 15)

The method of claim 15, wherein forming the crown comprises forming a first section using the additive manufacturing process, and forming a second section in isolation from the first section using the additive manufacturing process.

### Claim 18 (depends on 17)

The method of claim 17, further comprising:
positioning the first section onto the skirt;
positioning the second section onto the first section; and
joining both the first section and the second section to the skirt.