Suzuki Motor Corporation

Shizuoka University

Naoyuki Suda

Seiya Kunioka

Manabu Suzuki

Hitoshi Muramatsu

Akira Ishibashi

Masahiro Ogawa

Minoru Imai

Tomohiro Asou

Nobuyuki Suzuki

Kunio Hayakawa

A piston for an internal combustion engine has a plurality of recesses formed in a skirt including an upper, a lower, and a central portion. The recesses in the upper portion close to an upper boundary of the central portion have lower ends located upwardly at a given distance away from the upper boundary. The recesses in the central portion close to the upper boundary have upper ends located downwardly at the given distance away from the upper boundary. The recesses in the lower portion close to the lower boundary have upper ends located downwardly at the given distance away from the lower boundary. The recesses in the central portion closer to the lower boundary have lower ends located upwardly at the given distance away from the lower boundary. This enhances lubrication between the piston and an inner wall of a cylinder bore and reduces a friction loss of the piston.

Piston for internal combustion engine

[Problem to be Solved] A space from a skirt to a side wall is uniformly deformed in a wide range without a bias. [Solution] A pistonhas two pin bossesdisposed so as to face each other at an interval, a side walldisposed on both sides of the pin boss, and a skirtprovided continuously to the side wall, and a pin holeinto which a piston pina can be inserted is formed in the pin boss. Inner wallsof the side walland the skirtare continuous with each other and disposed by facing on both sides of a pin boss axis Cwith the pin boss axis Cbetween them. A horizontal section of the inner wallis formed along a specific oval shape E.

A resin coat filmformed on a skirt portionof a pistonhas a four-sided outer peripheral region knurled at upper and lower regions thereof corresponding in a rear view of the pistonto an upper skirt partand a lower skirt partof the skirt portionextending in parallel with an axial direction of left and right piston pin boss portionsand, with a combination of short vertical groovesA andB and medium-length vertical groovesA andB extending in parallel with a central axis C of a piston crow portion, and at left and right edge regions thereof, with long vertical grooves

Piston for internal combustion engines

A plating pretreatment apparatus for a multi-cylinder block includes a plurality of cylinders that performs a plating pretreatment of a cylinder inner wall surface of each of the cylinders using an electrode disposed so as to oppose to the cylinder inner wall surface by sealing one end of the cylinder inner wall surface and introducing a treatment liquid to the cylinder inner wall surface. In such plating pretreatment apparatus, at least one of a power supply device that supplies electricity to the cylinder block and the electrode and a liquid feed pump that feeds the treatment liquid into a gap between the cylinder inner wall surface and the electrode is provided for each of the cylinders.

Plating pretreatment apparatus and method for multi-cylinder block

A cylinder block plate processing apparatus in which one end side of an inner peripheral surface of a cylinder of a cylinder block is sealed to circulate a process liquid to perform pre-plating or plating processing of the cylinder inner peripheral surface. The apparatus includes: an apparatus body having a workpiece mount table on which the cylinder block is placed; a workpiece holding tool that is provided on the workpiece mount table so as to be vertically movable; an electrode support member including an electrode cylinder mounted to the apparatus body; a processing solution supply member that supplies a processing solution to the electrode support member; an electrode operated by the electrode cylinder; a sealing jig provided to one end of the electrode; a driving mechanism that drives the sealing jig; and a control circuit that controls operations of the processing solution supply member and the driving mechanism.

Cylinder block plate processing apparatus and sealing mechanism of the same

The present invention provides an apparatus for plating pretreatment of a cylinder block that includes an electrode performing a plating pretreatment of the cylinder inner wall surface. A gap flow channel communicates with an in-electrode flow channel at a position closest to a seal jig, the gap flow channel being adapted to introduce a treatment liquid to the cylinder inner wall surface, the in-electrode flow channel being adapted to receive the treatment liquid having passed through a communicating hole. The present invention is provided a method for pretreating before plating a cylinder block including disposing an electrode to face the cylinder inner wall surface so as to form a gap flow channel, and introducing a treatment liquid to the gap flow channel thereby flowing through the treatment liquid toward a seal jig and then into an in-electrode flow channel through a communicating hole.

Growing community of inventors

Hamamatsu, Japan

Naoyuki Suda