Nissan Motor Company Limited

Eiji Shiotani

Daisuke Terada

Yoshitsugu Noshi

Akira Shimizu

Hideo Takahashi

Takashi Ogino

Naoki Okamoto

Kiyokazu Sugiyama

Hidenobu Matsuyama

Hirohisa Shibayama

Yoshito Utsumi

Kimio Nishimura

Koukichi Kamada

Takashi Sekikawa

Takafumi Watanabe

Hirotaka Miwa

Kiyohisa Suzuki

Akiharu Tashiro

Mitsuo Hayashi

Yoshiaki Miyamoto

Kazuaki Taniguchi

Masahiko Iizumi

Naoya Tainaka

Haruhiko Suzuki

Jun Inomata

Koichi Kanai

Satoru Sakurai

Kei Fujii

Takayuki Monchujo

Masahito Fujikawa

Junichi Hamasaki

Toshio Ogiya

Kiyoshi Hasegawa

Hiroaki Mochida

Masami Tashiro

Ryuji Fukada

Junichi Uchiyama

Masatoshi Inoguchi

Takashi Iiya

Hiroshi Hatta

Shuji Adachi

Kiyokazu Sugiyma

A film forming method forms a coating film on a workpiece having at least two film-deposited portions which are not continuous with each other by moving a nozzle of a cold spray device relative to each other along a continuous movement trajectory. The movement trajectory includes at least two trajectories corresponding to the film-deposited portions and a connecting trajectory linking the trajectories of the film-deposited portions. The film-deposited portions are formed by continuously spraying a raw material powder from the nozzle by cold spraying to form a coating film on each of the plurality of film-deposited portions. A turnback point of the spraying is set on the connecting trajectory where a relative speed between the workpiece and the nozzle decreases in the movement trajectory.

Film forming method

The nozzle for cold spray () used in a cold spray apparatus () is configured to include a tubular nozzle main body () and a cooling jacket () that surrounds the nozzle main body () to form a flow path () for refrigerant (R) between the nozzle main body () and the cooling jacket (). The cooling jacket () is provided with a seal retaining portion () that retains an O-ring () for the flow path (). The seal retaining portion () and the nozzle main body () are joined in a socket-and-spigot joint fashion.

Cold spray nozzle and cold spray device

A film forming method forms a coating film on a workpiece (e.g., a cylinder head) having a film-deposited portion (e.g., an annular valve seat part) by moving a nozzle of a cold spray device relative to the workpiece along a film formation trajectory having a film formation starting point and a film formation finishing point in which the film-deposited portion overlaps to form an overlapping portion. The coating film is formed by causing a raw material powder to collide in a solid-phase state with the workpiece and plastically deform. Also, the coating film on the film-deposited portion is further formed such that an inclination angle of an end part of the coating film relative to a surface of the film-deposited portion is 45&#xb0; or less at the film formation starting point of the overlapping portion.

Film formation method

When forming valve seat coats at opening portions (to) of intake ports () provided at a cylinder block mounting surface () of a semimanufactured cylinder head (), the nozzle of a cold spray apparatus moves along a nozzle movement path for air intake (Inp) that is set between any two of the plurality of opening portions (to), while continuing to spray a raw material powder. When forming valve seat coats at opening portions (to) of exhaust ports (), the nozzle moves along a nozzle movement path for air exhaust (Enp) that is set between any two of the plurality of opening portions (to), while continuing to spray the raw material powder.

Coating method

Provided is a defect detection device capable of measuring the volume of surface defects. The defect detection device includes: an imaging device configured to image an image of an inspection object; a binarization processing unit configured to subject the image to first and second binarization processing by use of different first and second binarization thresholds, so as to calculate first and second sizes for an identical defect in the image; a ratio calculation unit configured to calculate a first ratio of the second size to the first size; and a depth determination unit configured to determine a depth of the defect depending on the first ratio.

Defect detection device and production system

A thermally sprayed coating is formed on an inner surface of a cylinder bore of a cylinder block by using a thermal spray gun. The thermal spray gun is reciprocated along an axial direction in the cylinder bore while being rotated, and injects melted droplets generated by melting a wire made of a ferrous material from a nozzle at its end. At this time, a moving speed of the thermal spray gun along the axial direction into the cylinder bore is made equal-to or larger-than a predetermined value, and the number of reciprocating cycles of the thermal spray gun along the axial direction into the cylinder bore is made equal-to or larger-than a predetermined value.

Method for manufacturing cylinder block and cylinder block

In a method for manufacturing a cylinder block provided with cylinder bores, the cylinder block is held by a clamp device, stress is generated in the cylinder block by a holding force of the clamp device to duplicate deformations of the cylinder bores after assembling hearing caps thereon, boring is carried out with the cylinder bores deformed in a condition where the stress is generated, and a thermally sprayed coating is formed, after the boring, on each inner surfaces of the cylinder bores deformed in the condition where the stress is generated. According to the method for manufacturing a cylinder block, superior cylindricity, after assembling the bearing caps, of the cylinder bores on each of which the thermally sprayed coating is formed can be brought, and workability degradation of finishing works (honing) for each inner surface of the cylinder bores (thermally sprayed coatings) can be restricted.

Method for manufacturing cylinder block

A cylinder block manufacturing method including: machining an inner surface of a cylinder bore () of a cylinder block () into a first shape different from a target shape before a bearing cap () is attached to the cylinder block () so that the inner surface of the cylinder bore () is deformed into the target shape by attachment of the bearing cap () to the cylinder block (); and forming a thermal spray coating () on the inner surface of the cylinder bore () having the first shape.

Cylinder block manufacturing method and cylinder block

A cylindrical internal surface processing method comprises forming a cylinder bore, roughening an upper section of the bore, depositing coating onto the bore, and machining a lower section of the bore and the coating. The forming of the cylinder bore includes forming the upper and lower sections with the lower section being axially spaced from the upper section and having an axial length greater than zero. The roughening creates a roughened surface such that a radially innermost edge of the roughened surface has an internal diameter smaller than an internal diameter of the lower section. The coating is deposited to cover the upper section and at least a portion of the lower section. The machining forms a tapered portion and a cylindrical portion, a radially outermost edge of the cylindrical portion having an internal diameter larger than that of a radially outermost edge of the roughened surface.

Cylindrical internal surface processing method

An apparatus is provided to reduce the defect rate and decrease production yield by removing foreign objects even when the foreign objects are mixed in with the thermally sprayed film. The operation for forming thermally sprayed film on inner surface of cylinder bore is paused, and protrusions generated in the thermally sprayed film by foreign objects are detected by visual observation and removed by a manual operation. The thermal spraying operation is then performed until thermally sprayed film reaches the prescribed film thickness. After formation of the thermally sprayed film, a finishing operation is performed by means of honing.

Thermally sprayed film forming method and device

The adhesiveness of a thermal spray coating and a cylinder internal surface is improved by forming a sufficient roughened surface on an internal surface. A processing roller is installed on the main shaft of a processing device via a pressurizing mechanism. An uneven surface is provided on the external periphery of the processing roller. By pressing the processing roller against the internal surface while the roller rotates and moves, a fine unevenness that corresponds to the unevenness of the roller is formed on the cylinder internal surface. A thermal spray coating is formed on the internal surface where the inner surface has been roughened by forming the above-mentioned unevenness.

Thermal spraying preprocessing method and a cylinder block of an engine so preprocessed

A method for processing a cylinder block is disclosed, wherein a protrusion protruding toward a crankcase is provided at a crankcase-side edge of a cylinder bore and a sprayed coating is formed on an inner surface of the cylinder bore and an inner surface of the protrusion continuous with the inner surface of the cylinder bore. After forming the sprayed coating, at least part of the protrusion is removed together with the sprayed coating formed on the inner surface of the protrusion. Accordingly, even in the case of removing the edge portion of the cylinder bore on the crankcase side, a sufficient margin to be removed can be ensured while a reduction in size of the cylinder block is achieved.

Method for processing cylinder block, cylinder block and thermal-sprayed cylinder block

A sprayed film forming method and apparatus in which the thickness of the sprayed film in a predetermined region is increased so as to unify the entire thickness. A sprayed film is formed at a cylinder bore inner surface while a spraying gun is moved in an axial direction during rotation inside the bore. Air inside the bore is sucked out to prevent foreign material from being caught in the sprayed film. The flow rate inside the bore tends to become higher at an axial end on a suction side, resulting in a thinned region. The supply speed of a wire serving as a spraying material to the spraying gun or the number of sprays in this region is higher than those at other portions. The thickness at the axial end of the bore is made equal while suppressing an increase in working time and spraying material used.

Method of forming sprayed film on the inner surface of a bore

A honing method and honing control device suitable for the honing having a large processing area is provided. The honing control device includes a grinder and an expansion member for disposition in a processing hole of a workpiece. The amount of an expanding movement when the grinder contacts the inner surface of a gauge hole via the expansion member is stored as a target expansion amount by inserting a honing head into the gauge hole having the same size as a target processing diameter of a master gauge. Then, a honing of an inner surface of the processing hole is performed by inserting the honing head within a processing hole of a workpiece moving the grinder towards an outer side of a diametrical direction by the expansion member installed within the honing head to rotate the honing head. The honing is completed when the amount of the expanding movement of the grinder reaches a target expansion amount established by the master gauge.

Honing method and honing control device

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Kawasaki, Japan

Eiji Shiotani