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US 4,522,163 AGranted
Stepped piston and stepped piston engine
OwnerBernard Hooperinventor
Life of this patent
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OwnerBernard Hooperinventor
Estimating the term…
A stepped piston for an engine of the kind having one or more cylinders, the or each cylinder containing a stepped piston having a pumping part of larger diameter, and a working part of smaller diameter, the working part of the piston being slidable in, and associated with, a working part of the cylinder in which combustion of a fuel/air mixture takes place, and the pumping part of the piston being slidable in, and associated with, a pumping part of the cylinder, the piston having a body with an interior hollow opening to the outside of a lower end of the piston, the body comprising a smaller diameter working, part, extending from the top of the piston to a step, and a larger diameter, pumping, part extending from the step to a lower end of the piston, at least one piston ring groove formed in an outer surface of the smaller diameter part and at least one piston ring groove formed in the outer surface of the larger diameter part, each piston ring groove, in use, receiving a piston ring the smaller diameter part of the piston having at least one metering opening providing a through passage for lubricant, between the interior the piston and the outer surface of the smaller diameter part of the piston.
A stepped piston for an engine of the kind having at least one cylinder, the cylinder comprising a pumping part of a first diameter and a working part of a second diameter, combustion of a fuel/air mixture taking place in the working part of the cylinder, the first diameter of the pumping part being greater than the second diameter of the working part, the piston comprising a body with a smaller diameter working part slidable in the working part of the cylinder, and a larger diameter pumping part slidable in the pumping part of the cylinder, the working part extending from the top of the piston to a step, and the pumping part extending from the step to a lower end of the piston, an interior hollow opening to the outside at the lower end of the piston, at least one piston ring groove formed in an outer surface of the working part of the piston, and at least one piston ring groove formed in another surface of the pumping part of the piston, each piston ring groove, in use, receiving a piston ring, at least two metering openings providing controlled flow of a predetermined amount of lubricant from the interior hollow to the outer surface of the working part of the piston, the total cross-sectional area of the openings being of an amount in the range determined according to the formula:
A stepped piston for an engine of the kind having at least one cylinder, the cylinder comprising a pumping part of a first diameter and a working part of a second diameter, combustion of a fuel/air mixture taking place in the working part of the cylinder, the first diameter of the pumping part being greater than the second diameter of the working part, the piston comprising a body with a smaller diameter working part slidable in the working part of the cylinder, and a larger diameter pumping part slidable in the pumping part of the cylinder, the working part extending from the top of the piston to a step, and the pumping part extending from the step to a lower end of the piston, an interior hollow opening to the outside at the lower end of the piston, at least one piston ring groove formed in an outer surface of the working part of the piston, and at least one piston ring groove formed in an outer surface of the pumping part of the piston, each piston ring groove, in use, receiving a piston ring, a metering opening providing controlled flow of a predetermined amount of lubricant from the interior hollow to the outer surface of the working part of the piston, the cross-sectional area of the opening being of an amount in the range determined according to the formula:
A stepped piston engine of the kind having at least one cylinder, the cylinder comprising a pumping part of a first diameter, and a working part of a second diameter, combustion of a fuel/air mixture taking place in the working part of the cylinder, the first diameter being greater than the second diameter, and a stepped piston within said cylinder, said stepped piston comprising a body with a smaller diameter working part slidable in the working part of the cylinder, and a larger diameter pumping part slidable in the pumping part of the cylinder, the working part extending from the top of the piston to a step, and the pumping part extending from the step to a lower end of the piston, an interior hollow opening to the outside at the lower end of the piston, at least one piston ring groove formed in an outer surface of the working part of the piston, and at least one piston ring groove formed in an outer surface of the pumping part of the piston, each piston ring groove, in use, receiving a piston ring, at least two metering openings providing controlled flow of a predetermined amount of lubricant from the interior hollow to the outer surface of the working part of the piston, the total cross-sectional area of the openings being of an amount in the range determined according to the formula:
Dependencies are inferred from the claim text.