Internal combustion engines that use the pumping motion of the engine pistons to supercharge the cylinder with air/charge are disclosed. The pistons may include a skirt with a field of pockets that provide a ringless, non-lubricated, seal equivalent. The piston heads may be domed with one or more depressions to facilitate the movement of air/charge in the cylinder. The engines also may have non-circular, preferably rectangular, cross-section pistons and cylinders. The engines also may use multi-stage poppet valves in lieu of conventional poppet valves, and may include a split crankshaft. The engines also may operate in an inverted orientation in which the piston is closer to the local gravitationally dominant terrestrial body's center of gravity at top dead center position than at bottom dead center position.

Internal combustion engines that use the pumping motion of the engine pistons to supercharge the cylinder with air/charge are disclosed. The pistons may include a skirt with a field of pockets that provide a ringless, non-lubricated, seal equivalent. The piston heads may be domed with one or more depressions to facilitate the movement of air/charge in the cylinder. The engines also may have non-circular, preferably rectangular, cross-section pistons and cylinders. The engines also may use multi-stage poppet valves in lieu of conventional poppet valves, and may include a split crankshaft. The engines also may operate in an inverted orientation in which the piston is closer to the local gravitationally dominant terrestrial body's center of gravity at top dead center position than at bottom dead center position.

The first to ninth crank webs are roughly divided into three groups. The first group is from the second, fifth and eighth webs. These crank webs of the first group have similar shapes. In the crankshaft, the shapes of these crank webs belonging to the first group are adjusted to satisfy the first stiffness condition below.
First stiffness condition:the second and eighth webs>the fifth web W5

The first to ninth crank webs are roughly divided into three groups. The first group is from the second, fifth and eighth webs. These crank webs of the first group have similar shapes. In the crankshaft, the shapes of these crank webs belonging to the first group are adjusted to satisfy the first stiffness condition below.
First stiffness condition:the second and eighth webs>the fifth web W5

A crankshaft damper for attachment to one end of a crankshaft of an engine. The crankshaft damper includes an elastomeric member attached to a hub, and an inertia ring connected to the hub through the elastomeric member. Several different structures for cooling the elastomeric member are disclosed that dissipate heat away from the elastomeric member. Air flow is induced near the elastomeric member by providing air flow openings in the inertia ring or the elastomeric member.

The present disclosure provides a reciprocating plunger pump, which includes a plunger pump engine body, a plunger pump head and a slider crank mechanism which is located in the plunger pump engine body. Also disclosed are a reciprocating plunger pump engine body, a slider crank mechanism and a slide block, a bearing seat, a crankcase upper cover and a plunger seat.

The present disclosure provides a reciprocating plunger pump, which includes a plunger pump engine body, a plunger pump head and a slider crank mechanism which is located in the plunger pump engine body. Also disclosed are a reciprocating plunger pump engine body, a slider crank mechanism and a slide block, a bearing seat, a crankcase upper cover and a plunger seat.

The first to ninth crank webs are roughly divided into three groups. The first group is from the second, fifth and eighth webs. These crank webs of the first group have similar shapes. In the crankshaft, the shapes of these crank webs belonging to the first group are adjusted to satisfy the first stiffness condition below.

First stiffness condition:the second and eighth webs>the fifth web W5

The first to ninth crank webs are roughly divided into three groups. The first group is from the second, fifth and eighth webs. These crank webs of the first group have similar shapes. In the crankshaft, the shapes of these crank webs belonging to the first group are adjusted to satisfy the first stiffness condition below.

First stiffness condition:the second and eighth webs>the fifth web W5

Methods and systems are provided for the design and manufacture of a crankshaft of a piston internal combustion engine. In one example, a crankshaft comprises a crankshaft throw, the crankshaft throw comprising a crankpin and crank webs. The crank webs are formed asymmetrically in a region of the crankpin with respect to a plane intersecting an axis of rotation of the crankshaft and a center axis of the crankpin, such that the breaking strength of the crankshaft throw is increased at a crankshaft angle of rotation which differs from the top dead center position of a piston to which the crankpin is coupled, and at which the piston exerts a maximum combustion-induced force on the crankpin.