Filing Information

Inventor(s)	Paul McLachlan ·
Assignee(s)	Pivotal Engineering Limited ·  View assignee updates
Correspondent	D. PETER HOCHBERG CO. L.P.A. ·
Application Number	US11396733
Filing date	04/03/2006
Publication date	08/10/2006
Predicted expiration date	03/23/2021
U.S. Classifications	123/18.00R  · 123/193.6  ·
International Classifications	F01C900  · F02F300  ·
Kind Code	A1
Foreign Priority	NZ338015 - 03/23/2000 ·

Patent Family

Abstract

A pivoted piston for an internal combustion engine. The piston has a pivot pin and an arcuate first sealing surface (12) which describes a circumferential path about the pivot pin which forms a removable and replaceable skirt to the piston. The piston also includes a second arcuate sealing surface which also describes a circumferential path about the pivot pin and which is connected to the first arcuate sealing surface (12) by a piston floor (21). The second arcuate sealing surface is composed of at least two arcuate sealing components (24) which are located on a bed (20) with the components (24) being located on the bed (20) so they will have limited transverse movement on the bed (20). The components (24) have mating faces which restrict the path of combustion gases between the mating faces. The piston further includes side seals which are located in grooves (63) in the side of the piston. A restraining pin (60) assists in locating the seals in the seal grooves (63) and also closes a pressure escape path for the combustion gases. The piston further includes means to allow liquid coolant to pass through the pivot shaft, through liquid cooling galleries in the piston and out of the pivot shaft.

Independent Claims | See all claims (14)

1. 1. A pivot piston for an internal combustion engine, said piston having a first arcuate seal and a second arcuate seal with both seals transcribing a circumferential path about the pivot axis of the piston, the first arcuate seal being radially offset from the second arcuate seal, said piston having a floor extending between the first and second arcuate seals, wherein a coolant path for cooling medium independent of the lubricant for the engine is provided within the piston and wherein the coolant path further comprises an entrance from the pivot pin, through galleries formed in the piston and an exit from the pivot pin.
2. 2. A piston for an internal combustion engine, said piston having a first end; a second end spaced from the first end; a pivot axis adjacent the first end of the piston, the piston being pivotable about the pivot axis within a combustion chamber of the internal combustion engine; a first arcuate sealing surface adjacent the second end of the piston, said first arcuate sealing surface transcribing a circumferential path about the pivot axis; a second arcuate sealing surface radially offset towards the pivot axis from the first arcuate sealing surface, said second arcuate sealing surface transcribing a circumferential path about the pivot axis; a piston floor located between the first and the second arcuate sealing surfaces; apparatus remote from the pivot axis, said apparatus pivotally connecting said piston to a connecting rod connectable to a crankshaft enabling pivotal movement of the piston about the pivot axis resulting in rotation of the crankshaft; and a coolant path comprising a gallery formed within the piston and having an entrance and an exit external to the engine, said entrance and said exit for coolant medium independent of the lubricant for the engine.
3. 3. A piston for an internal combustion engine, said piston being constrained to have a rocking motion about a pivot axis, said piston comprising: a first arcuate sealing surface transcribing a first circumferential path about the pivot axis; a seal bed; a second arcuate sealing surface radially offset from said first sealing surface and transcribing a second circumferential path about the pivot axis, said second arcuate sealing surface including at least two components located contiguously on said seal bed, said components having contiguous edges forming mating edges to allow said components to have independent transverse movement on said seal bed and restrict the path of combustion gases between the mating edges; a floor extending substantially radially between said first arcuate sealing surface and said second arcuate sealing surface; and a coolant path for cooling medium formed in the piston comprising an entrance from the pivot pin, through galleries in the piston and an exit from the pivot pin.