Denso Corporation

Denso Preas Co., Ltd.

Shoichi Takenouchi

Kazuhiro Mitsukawa

Kuniharu Teshima

Fumio Kondo

Mikiya Kurita

Takayuki Nakanishi

Osamu Matsui

A plurality of press devicesare arranged in a plastic working system. The plastic working system includes: a loop correction sensorfor watching a slack of a coil material C intermittently delivered from a preceding first press device; and a second slack watching meansfor watching a slack of the coil material C generated at the time of sending the coil material C to a succeeding second press device. According to the slack generated by intermittent feeding of the coil material C sent from the first press device, intermittent feeding is converted to continuous feeding by the feeding means. At the same time, the continuous feeding speed is subjected to speed increasing/decreasing control. On the other hand, by the second slack watching means, a slack of the coil material C is watched at the time of feeding the coil material C to the second press deviceand the preceding first press deviceis subjected to speed increasing/decreasing control.

Plastic working method and plastic working system

A die rollcomprises a core partwhich is formed of an elastic material and faces a punch partof a punch rollThe core partpresses a bottom portionof a drawn portionof a metal materialand is separate from a surrounding die partand is provided with a spaceat the whole outer periphery of the core partIn accordance with the above configuration, swelling is suppressed at the bottom portionof the drawn portionand production of large wrinkles, which is a reason for folds, can be prevented by increase of pressing areas for preventing wrinkles at both sides of the drawn portion.

Method for roll forming, capable of preventing wrinkles and device therefor

In a method for manufacturing a nozzle hole plate suitable for use in a fuel injection valve, a nozzle hole is formed at a predetermined angle of inclination by press-working with a punch in a thin-plate base material of a nozzle hole plate. When the nozzle hole is formed by press-working, a bluntness (shear drop) and a break face are formed at the corners of the base material at the fluid entrance and the fluid exit of the nozzle hole respectively, and as a result of the formation of this shear drop and break face the flow changes and the injection quantity increases. The injection quantity of the nozzle hole is measured for each nozzle hole plate, and its deviation from a target value is detected. Then, on the basis of the measured injection quantity value, the base material around the fluid entrance of the nozzle hole is notched by press-working using a punch. The material of the base material dimpled by the notching is pushed toward the fluid entrance of the nozzle hole and the shear drop diminishes. Consequently, the quantity of fuel injected through the nozzle hole plate decreases. Thus it is possible to provide a nozzle hole plate and a manufacturing method thereof with which a required injection quantity can be obtained in a short working time.

Nozzle hole plate and its manufacturing method

Growing community of inventors

Toyokawa, Japan

Shoichi Takenouchi