To provide an electro-rheological fluid and a cylinder device, which each can achieve both high heat resistance and a high ER effect. The electro-rheological fluid (300) of the present invention includes a fluid (30) and polyurethane particles (31) containing metal ion. The polyurethane particles (31) are each composed of polyol and two or more types of isocyanates. A hard segment ratio of the polyurethane particle (31) is 13 to 34%.

A leaf spring suspension system for a vehicle includes an axle. The leaf spring suspension system includes a leaf spring having a top side, a bottom side, and a pair of side edges, wherein at least one of the side edges defines a pair of recesses extending inwardly from the side edge. The leaf spring suspension system also includes a clamping assembly operatively coupling the leaf spring to the axle, the clamping assembly comprising a pair of U-shaped bars, wherein a portion of the U-shaped bars is disposed within the pair of recesses of the leaf spring.

A bi-metallic component including a tubular stud member extending from an open first end to an open second end, and a cast member cast around the open second end of the tubular stud member is provided. The cast member is formed from first material, such as an aluminum alloy; and the tubular stud member is formed from a second material, such as steel. The tubular stub member has an interior surface which sealingly receives a removable core member for preventing molten first material from flowing through the stub member between the open ends thereof during casting of the cast member around the second end. The bi-metallic component can be used in a variety of automotive applications, for example in a cradle, frame, twist axle, control arm, door pillar, instrument panel support, or bumper assembly.

A damper includes a pressure tube extending about a longitudinal axis and defining an inner volume. The damper includes a piston attached to a piston rod and slidably disposed within the pressure tube. The piston divides the inner volume of the pressure tube into a first working chamber and a second working chamber. The damper includes a fluid connector having a first wall and a second wall, each elongated along the longitudinal axis and sealed to the pressure tube. The fluid connector has a third wall elongated along the longitudinal axis and extending from the first wall to the second wall. The pressure tube defines an opening at the first working chamber, and the third wall of the fluid connector defines an opening spaced from the opening of the pressure tube. The first wall, the second wall, and the third wall define a passage extending from the opening of the pressure tube to the opening of the third wall.

The invention relates to a spring arm device (1) for a motor vehicle, comprising two flanges (2) arranged at a distance from each other and which are made of a first fiber composite material (4) having fibers (6) each oriented in a longitudinal direction (5) of the flanges (2). The spring arm device (1) also comprises a web (3) which connects the flanges (2) and is made of a second fiber composite material (7) having the fibers (8) oriented at positive angles to the longitudinal directions (5) of the flanges (2). The spring arm device (1) can be fastened in end regions (15) opposite to each other to vehicle parts as part of a wheel suspension. The end regions (15) comprise end segments (14) of the two flanges (2) associated with each other and each comprise an end segment (9) of the web (3) that connects the end segments (14) of the flanges (2). Respective forces applied to the spring arm device (1) in the longitudinal direction (5) by means of the end regions (15) can be transmitted by means of the flanges (2). By means of a spring force, the flanges (2) counteract deformation of the spring arm device (1) caused by forces acting in a normal direction (16) of the web (3). Forces acting on the spring arm device (1) in a transverse direction (13) are transmitted from the web (3) to the end regions (15).

The invention relates to a suspension unit, in particular for commercial vehicles, including an arm and a support element. The support element includes a support region and a support-side engagement region and comprises as a single piece, and the arm has an arm-side engagement region. A first engaging structure is provided on the arm-side engagement region, the engaging structure being attachable to a second engaging structure located on the support-side engagement region, and the support region includes a securing portion that fixes an air spring bellows and a rolling surface.

To provide a lubricant composition for shock absorbers, a friction adjusting additive for a lubricant for shock absorbers, and a lubricant additive, each capable of satisfying both operational stability and ride comfort and improving the ride comfort further. The lubricant composition for shock absorbers contains a base oil and a friction adjusting agent and the friction adjusting agent contains a first zinc dithiophosphate represented by the following formula 1:

##STR00001##

[in the formula 1, R.sup.11 to R.sup.14 are alkyl groups in which one or more and three or less is/are a primary alkyl group and the other(s) is/are a secondary alkyl group].

An embodiment composite material spring for a suspension device of a vehicle includes a leaf spring configured to be installed in a body of the vehicle and a wheel of the vehicle, a first fluid container installed at a left side of a center of the leaf spring and including a first magnetorheological fluid, and a second fluid container installed at a right side of the center of the leaf spring and including a second magnetorheological fluid.

A chassis control arm for a wheel suspension has a control arm body, a spring abutment and an actuator which is arranged between the control arm body and the spring abutment and with which the position of the spring abutment relative to the control arm body can be adjusted. The actuator comprises a lifting gear which is configured as a movement thread and which includes a lifting spindle on which the spring abutment is arranged or on which the spring abutment is axially movably mounted.

Provided is a shock absorber in which trivalent chromium is used to achieve both high hardness and low frictional force at a high level without using hexavalent chromium which is suspected of causing damage to the human body and the environment, and a method for manufacturing the shock absorber.

A shock absorber (100) of the present invention includes: a cylinder (1) which is filled with hydraulic oil (3); a piston rod (2) which is movable in the cylinder (1); and an oil seal (8) which is fixed to the cylinder (1) and slides on the piston rod (2), in which a hard layer mainly containing chromium obtained from a trivalent chromium plating bath is provided on a surface of the piston rod (2), and the hard layer contains both a crystalline material and an amorphous material, and also contains an additive other than chromium.