Hitachi Automotive Systems, Ltd.

Hitachi Astemo Ltd.

Umi Tanabe

Shigeo Katayama

Yusei Kimura

Yohei Katayama

Yasuhiro Aoki

Hideki Hata

Osamu Yuno

Tomoyuki Ri

Osamu Shioume

Hiroyuki Matsumoto

Motohiro Hirao

Yoshie Midorikawa

Electrorheological fluid is loaded in a shock absorber () as hydraulic fluid (). The shock absorber () controls a generated damping force by causing a potential difference to be generated in an electrode passage () and controlling a viscosity of the electrorheological fluid passing through this electrode passage (). A plurality of partition walls () is provided between an inner cylinder () and an electrode cylinder (). By being configured in this manner, the shock absorber () forms a plurality of helical flow passages () between the inner cylinder () and the electrode cylinder (). In this case, an inclination angle of each of the partition walls () is not constant, and each of the partition walls () includes a sharply inclined portion (A) inclined at a large angle on at least an entrance side of an extension-side flow passage ().

Cylinder apparatus

An intermediate cylinder is disposed between an outer cylinder and an inner cylinder. The intermediate cylinder forms a passage between the inner cylinder and itself, through which a hydraulic fluid as an electrorheological fluid flows. The intermediate cylinder is supplied (applied) with a voltage through an electrode connector. The intermediate cylinder includes a ring member. The ring member is provided with an extending portion which extends toward the outer cylinder. The extending portion of the ring member is inserted with an electrode pin as an imparting unit for imparting a voltage to the intermediate cylinder.

Cylinder device

A cylinder device includes: an inner cylinder in which a functional fluid, a fluid property of which is changed due to an electric field or a magnetic field, is encapsulated; an outer cylinder provided outside the inner cylinder; an intermediate cylinder provided between the inner cylinder and the outer cylinder to serve as an electrode or a magnetic pole; a rod guide provided to close the one end side end portions of the inner cylinder and the outer cylinder; a spacer having one end located at the rod guide side and the other end located at the one end side of the intermediate cylinder, and fitted to the inner cylinder; and an elastic seal member disposed in a portion of the other end of the spacer, and configured to seal the one end side end portion of the passage between the intermediate cylinder and the inner cylinder.

A space between an inner surface of a cover and a housing is set to be wider on a spaced-apart side from a cylinder than on a cylinder side. Therefore, the cover is generally integrated with the housing at the moment that the cylinder side abuts against the housing, which can improve stiffness. This can prevent the cover from contacting a solenoid located on the spaced-apart side of the housing that is spaced apart from the cylinder.

Shock absorber

A shock absorber includes a reservoir between a cylinder and an outer tube, in which hydraulic liquid and gas are sealed; a middle tube between the cylinder and the outer tube; a connecting pipe in the lateral wall of the middle tube, which includes a tip end extending toward the outside of the outer tube; an opening in the outer tube, allowing hydraulic liquid to flow from the outside of the outer tube into the reservoir through the outer side of the connecting pipe; and a partition member in the reservoir, which includes a partition wall that configured to regulate hydraulic liquid's upward flow from the opening in the reservoir. The partition member is made of flexible resin or rubber, provided with a fitting hole, and fitted to the connecting pipe with interference with the connecting pipe inserted through the hole.

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Kawasaki, Japan

Umi Tanabe