Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Masaya Nagao

Masashi Nishida

Hiroki Kitagawa

Yoshiichi Komazaki

Tetsuhito Shige

Shouichi Hirai

Kousuke Akutsu

Yoshimitsu Iijima

Akiyuki Miyazaki

A fastening tool is provided, wherein a relief valve piston () is arranged that blocks an air passage from an air plug () to an accumulator chamber () and that opens/closes a flow path of a discharge port of compressed air from the accumulator chamber () to the atmosphere. When a state in which a trigger lever () is pulled while a push lever is released continues for a prescribed time or longer, a portion of the compressed air in the accumulator chamber () is released to the outside from the discharge port to notify the operator that the trigger lever () has not returned. If the trigger lever () is not returned even after the notification, the compressed air in the accumulator chamber () is discharged to the atmosphere at once and an air passage from an air plug () to the accumulator chamber () is blocked.

Fastening tool

A driving machine is provided to prevent clogging of a fastener in an ejection passage without increasing the total length of the ejection passage. A nail driving machine includes: a nose part forming an upper portion of an ejection passage through which a nail passes; a contact part being slidable along the nose part and forming a lower portion of the ejection passage; a driver blade striking a head part of the nail supplied to the ejection passage; and a guide part disposed in a lower portion of the nose part and guiding the nail passing through the ejection passage. The guide part has a guide surface inclining to protrude from a radial outer side toward a radial inner side of the ejection passage. A housing groove is formed in the contact part and the guide part enters the housing groove when the contact part slides along the nose part.

Driving machine

The nailing machine () comprises an air passage () allowing communication between a cylinder () and a return air chamber () in which compressed air for returning a piston () to the initial position is accumulated. The air passage () is provided with a control valve () controlling entry of compressed air into the return air chamber () from the cylinder (). The control valve () opens the air passage () and allows entry of compressed air into the return air chamber () in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body () relative to the push lever () is smaller than a predetermined distance. The compressed air that has entered the return air chamber () further enters a below-the-piston chamber and serves as air damper, reducing the driving force.

Pneumatic driving machine

The nailing machine () comprises an air passage () allowing communication between a cylinder () and a return air chamber () in which compressed air for returning a piston () to the initial position is accumulated. The air passage () is provided with a control valve () controlling entry of compressed air into the return air chamber () from the cylinder (). The control valve () opens the air passageand allows entry of compressed air into the return air chamber () in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body () relative to the push lever () is smaller than a predetermined distance. The compressed air that has entered the return air chamber () further enters a below-the-piston chamber and serves as air damper, reducing excess energy absorbed by a piston bumper ().

Growing community of inventors

Ibaraki, Japan

Masaya Nagao