Open-faced piston assembly

Patent metadata

Field	Value
Publication number	US-10669969-B2
Application number	US-201916452500-A
Country	US
Kind code	B2
Filing date	Jun 25, 2019
Priority date	Oct 14, 2016
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

The present disclosure provides an open-faced piston with a circumferential groove into which a piston ring assembly is arranged. Openings at the bottom of the circumferential groove and between a front land of the open-faced piston and the piston face are provided. The openings are arranged to allow for a combustion reaction to propagate through the volume defined between the bottom of the piston ring assembly and the piston face such that at least a portion of an air and fuel mixture located in that volume is reacted.

First claim

What is claimed is:

1. A piston assembly comprising:
a piston configured to be in contact with a combustion section, the piston comprising:
a circumferential groove that extends at least partially around an outer surface of the piston, and
a plurality of openings located along the circumferential groove; and

a piston ring assembly arranged within the circumferential groove, wherein each of the plurality of openings is sized and arranged such that a minimum opening along a gas path between each opening and the inner surface of the piston ring assembly is larger than a quench distance of an oxidizer and fuel mixture of the combustion section.

2. The piston assembly of claim 1 , wherein the piston further comprises a plurality of structural webs arranged between the plurality of openings.

3. The piston assembly of claim 1 , wherein the piston further comprises a front land configured to maintain the piston ring assembly within the circumferential groove.

4. The piston assembly of claim 1 , wherein the quench distance is approximately 1 mm.

5. The piston assembly of claim 1 , wherein a distance between an outer surface of the piston and the inner surface of the piston ring assembly is greater than 1 mm.

6. The piston assembly of claim 1 , wherein the piston assembly is configured for oil-less operation.

7. The piston assembly of claim 1 , wherein the piston ring assembly comprises a solid lubricating material.

8. The piston assembly of claim 1 , wherein the plurality of openings is configured to allow a combustion reaction to propagate into a volume defined between an inner surface of the piston ring assembly and the piston.

9. The piston assembly of claim 8 , wherein the combustion reaction propagates from the combustion section of an engine in which the piston assembly is configured to translate.

10. The piston assembly of claim 1 , wherein the plurality of openings comprises a plurality of spaced openings along the circumferential groove that comprise a majority of a surface area of a bottom of the circumferential groove.

11. An engine comprising:
a cylinder comprising a combustion section;
a piston assembly arranged within the cylinder, the piston assembly comprising:
an open-faced piston comprising:
a front land,
a circumferential groove that extends at least partially around an outer surface of the open-faced piston, the circumferential groove comprising a front side defined by the front land,
a piston face, and
a plurality of openings located along the circumferential groove and between the front land and the piston face; and

a piston ring assembly arranged within the circumferential groove, wherein each of the plurality of openings is sized and arranged such that a minimum opening along a gas path between each opening and the inner surface of the piston ring assembly is larger than a quench distance of an oxidizer and fuel mixture of the combustion section.

12. The engine of claim 11 , wherein the quench distance is approximately 1 mm.

13. The engine of claim 11 , wherein the plurality of openings is configured to allow a combustion reaction to propagate into a volume defined between an inner surface of the piston ring assembly and the open-faced piston.

Assignees

• Etagen Inc
• Mainspring Energy Inc

Inventors

• Svrcek Matt

Classifications

• F16J9/12

  Details · CPC title

• F16J1/09

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

• F02F3/28 Primary

  Other pistons with specially-shaped head · CPC title

• F02B71/00

  Free-piston engines; Engines without rotary main shaft · CPC title

• F16J9/08

  with expansion obtained by pressure of the medium · CPC title