Open-faced piston assembly

Patent metadata

Field	Value
Publication number	US-11313318-B2
Application number	US-202016874322-A
Country	US
Kind code	B2
Filing date	May 14, 2020
Priority date	Oct 14, 2016
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

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 comprising:
a circumferential groove that extends at least partially around an outer surface of the piston, wherein the circumferential groove is configured to accommodate a piston ring assembly; and
a radially inward wall of the circumferential groove, wherein a majority of the radially inward wall is comprised of a plurality of openings.

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

3. The piston of claim 1 , wherein each of the plurality of openings is larger than a quench distance of an oxidizer and fuel mixture of a combustion section in contact with the piston.

4. The piston of claim 3 , wherein the quench distance is approximately 1 mm.

5. The piston of claim 1 , further comprising:
a front land attached to a radially inward side of the circumferential groove and defining a front side of the circumferential groove; and
a piston face, wherein the plurality of openings extend to an area between the front land and the piston face forming a gas path from the piston face to the circumferential groove, wherein a minimum opening along the gas path is larger than a quench distance of an oxidizer and fuel mixture of a combustion section in contact with the piston.

6. The piston of claim 5 , wherein a front face of the front land extends radially inward to connect with the piston face.

7. The piston of claim 1 , wherein the circumferential groove is a first circumferential groove, further comprising a second circumferential groove arranged behind the first circumferential groove.

8. The piston of claim 1 , wherein the circumferential groove extends completely around the outer surface of the piston.

9. A piston assembly comprising:
a piston comprising:
a circumferential groove that extends at least partially around an outer surface of the piston, wherein the circumferential groove is configured to accommodate a piston ring assembly, and
a radially inward surface of the circumferential groove, wherein a majority of the radially inward surface is comprised of a plurality of openings; and

a piston ring assembly arranged within the circumferential groove.

10. The piston assembly of claim 9 , wherein the piston further comprises a plurality of structural webs arranged between the plurality of openings.

11. The piston assembly of claim 9 , wherein the piston further comprises a front land configured to maintain the piston ring assembly within the circumferential groove.

12. The piston assembly of claim 9 , wherein each of the plurality of openings is sized and arranged such that a minimum opening along a gas path between each opening and an inner surface of the piston ring assembly is larger than a quench distance of an oxidizer and fuel mixture of the combustion section.

13. The piston assembly of claim 12 , wherein the quench distance is approximately 1 mm.

14. The piston assembly of claim 9 , wherein a distance between an outer surface of the piston and an inner surface of the piston ring assembly is greater than 1 mm.

15. The piston assembly of claim 9 , wherein the piston assembly is configured for oil-less operation.

16. The piston assembly of claim 9 , wherein the piston ring assembly comprises a solid lubricating material.

17. The piston assembly of claim 9 , 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.

18. The piston assembly of claim 17 , wherein as the volume increases, the plurality of openings is configured to allow the combustion reaction to propagate into the volume regardless of the increasing volume.

19. A piston comprising:
a circumferential groove that extends at least partially around an outer surface of the piston, wherein the circumferential groove is configured to accommodate a piston ring assembly;
a piston face;
a front land attached to a radially inward side of the circumferential groove; and
a plurality of openings arranged between the piston face and the front land, wherein the plurality of openings form a gas path to the circumferential groove, and wherein at least a majority of the radially inward side of the circumferential groove comprises a plurality of openings.

Assignees

• Mainspring Energy Inc

Inventors

• Svrcek Matt

Classifications

• F16J9/08

  with expansion obtained by pressure of the medium · CPC title

• F02B71/00

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

• F16J1/09

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

• F16J9/12

  Details · CPC title

• F16J1/001

  One-piece pistons · CPC title