Fichtel & Sachs Ag

Mannesmann Sachs Ag

Werner Christel

Hermann Itzinger

Manfred Koller

Ernst Prozeller

Horst Drescher

Klaus Kundmuller

Erich Jager

An indentation in a surface of a plastically deformable material, in particular metal, having a curved section at the base of the indentation. The curved section is adjoined in the direction of the surface by a further section which has the shape of a parabola in cross section.

Indentation in a plastically deformable material

In a cylinder piston device the piston when approaching the end of the cylinder abuts against an indentation of the cylinder and is tilted or angled by the abutment, on the one hand, and by an axially directed force acting onto the piston rod, on the other hand. Thus, a clamping effect is obtained. By the clamping effect expulsion of the piston rod is prevented. Moreover, the tilting may result in a leakage condition of sealing rings. This allows pressurized fluid to escape. As a result, an increased security in case of high temperature development by fire is obtained.

Cylinder piston device

An impact damper for a motor vehicle comprises two fluid chambers. These fluid chambers are interconnected by a fluid passage. In case of an impact of the motor vehicle against an obstacle, the fluid flows from one fluid chamber to the other fluid chamber through the throttled passage. If the impact occurs with a high velocity beyond a predetermined velocity, the impact damper behaves like a rigid body. It may therefore occur that the vehicle is damaged to a higher degree than it would in case of lack of the impact damper. For preventing such situation, the passage is provided by perforated and sandwiched discs. One disc acts as a support disc, one other disc acts as a throttling disc. The throttling disc is provided with a weakening line and is broken at a predetermined pressure different between the two fluid chambers. After rupture has occurred, the flow resistance through the passage is reduced and therefore the rigid behavior of the impact damper is eliminated.

Impact damper

In a double-tube vibration damper the cylinder engages by a terminal edge thereof an engagement face of a piston rod guiding and sealing unit. When the piston rod moves in the outward direction with respect to the cylinder, a high pressure occurs in the working chamber adjacent the piston rod guiding and sealing unit. Due to this high pressure damping liquid jets may escape between the terminal edge of the cylinder and the engagement face of the piston rod guiding and sealing unit. These liquid jets may cause foaming within the annular space defined between the cylinder and a container surrounding the cylinder. In view of avoiding such foaming, an annular cover member is provided between the cylinder and the container, which annular cover member prevents the direct entrance of liquid jets into the annular space between the cylinder and the container. This annular cover member is situated such that it extends across the plane of engagement defined by the terminal edge of the cylinder and extends perpendicular with respect to the axis of the cylinder.

Double-tube vibration damper unit

A piston-cylinder unit for shock absorbers or the like is formed with a tubular container surrounding the cylinder and with a piston rod guide and sealing unit mounted at one end of the container with a support for the cylinder at the other end of the container. In order to effect a satisfactory sealing action at the fixing points of the cylinder, the cylinder is formed with a radial indentation.

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Hambach, Germany

Werner Christel