US 5,848,677 AGranted

Vibration damper for a motor vehicle and a piston cylinder assembly; such as for a vibration damper for a motor vehicle

AssigneeFichtel & Sachs AG

InventorsHubert Beck, Werner Kuchheuser, Wilhelm Wortmann

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Abstract

A piston cylinder assembly which includes a work cylinder, a piston and a piston rod, which piston rod carries the piston and extends out of the work cylinder in a sealed manner, as well as a ring-shaped equalization chamber formed by two tubes is disclosed. The equalization chamber is divided by a separating piston into two partial chambers, the separating piston having two parts which are guided so that they can move in a sealed manner axially on the wall of the respective tube of the compensation chamber facing the respective part. The two parts of the separating piston are connected by a flexible portion allowing them to move radially with respect to one another and are sealed with respect to one another.

Claims21

Dependent claims

A piston cylinder assembly for a vibration damper for a motor vehicle, said piston cylinder assembly comprising:

an outer tube member;
an inner tube member;
said inner tube member being positioned substantially within said outer tube member;
a first end and a second end;
a piston disposed within said inner tube member;
a piston rod connected to said piston and extending out of said first end;
said outer tube member and said inner tube member having a substantially common longitudinal axis;
said outer tube member and said inner tube member forming an annular chamber therebetween;
a separating piston disposed in said annular chamber;
said separating piston dividing said annular chamber into a first annular chamber portion and a second annular chamber portion;
said separating piston being disposed between said first annular chamber portion and said second annular chamber portion;
said separating piston being translatable in a direction substantially parallel to said substantially common longitudinal axis of said outer tube member and said inner tube member;
and
a hydraulic fluid disposed in at least one of said first annular chamber portion and said second annular chamber portion;
said separating piston comprising:
a first separating piston portion;
said first separating piston portion slidingly contacting said inner tube member and said first separating piston portion being translatable in said direction substantially parallel to said common longitudinal axis;
and
a second separating piston portion;
said second separating piston portion slidingly contacting said outer tube member and said second separating piston portion being translatable in said direction substantially parallel to said common longitudinal axis;
and
radially extensible fluid blocking structure to substantially block the flow of said hydraulic fluid between said first annular chamber portion and said second annular chamber portion through said separating piston, and to provide sufficient relative movement between said first separating piston portion and said second separating piston portion in a direction substantially oblique to said common longitudinal axis to compensate for manufacturing tolerances of one of said inner tube member and said outer tube member.

19 more elements

A vibration damper for damping vibration in a land motor vehicle, said vibration damper comprising:

a piston cylinder assembly;
said piston cylinder assembly having a first end and a second end;
a piston disposed within said piston cylinder assembly and dividing said piston cylinder assembly into first and second working chambers;
a piston rod connected to said piston and extending out of said first end of said piston cylinder assembly;
a first connecting apparatus disposed on said piston rod for connecting to a first portion of the motor vehicle;
a second connecting apparatus disposed on said second end of said piston cylinder assembly for connecting to a second portion of the motor vehicle;
a hydraulic fluid disposed in said first and second working chambers;
and
damping apparatus for damping a flow of said hydraulic fluid between said first and second working chambers;
said piston cylinder comprising:
an outer tube member;
an inner tube member;
said inner tube member being positioned substantially within said outer tube member;
at least a portion of said piston rod being disposed in said inner tube;
said outer tube member and said inner tube member having a substantially common longitudinal axis;
said outer tube member and said inner tube member forming an annular chamber therebetween;
a separating piston disposed in said annular chamber;
said separating piston dividing said annular chamber into a first annular chamber portion and a second annular chamber portion;
said separating piston being disposed between said first annular chamber portion and said second annular chamber portion;
said separating piston being translatable in a direction substantially parallel to said substantially common longitudinal axis of said outer tube member and said inner tube member;
and
said hydraulic fluid being disposed in at least one of said first annular chamber portion and said second annular chamber portion;
said separating piston comprising:
a first separating piston portion;
said first separating piston portion slidingly contacting said inner tube member and said first separating piston portion being translatable in said direction substantially parallel to said common longitudinal axis;
and
a second separating piston portion;
said second separating piston portion slidingly contacting said outer tube member and said second separating piston portion being translatable in said direction substantially parallel to said common longitudinal axis;
and
radially extensible fluid blocking structure to substantially block the flow of said hydraulic fluid between said first annular chamber portion and said second annular chamber portion through said separating piston, and to provide sufficient relative movement between said first separating piston portion and said second separating piston portion in a direction
substantially oblique to said common longitudinal axis
to compensate for manufacturing tolerances of one of
said inner tube member and said outer tube member.

30 more elements

A piston cylinder assembly for a motor vehicle, said piston cylinder assembly comprising:

a first tube member having a cylindrical exterior wall;
a second tube member having a cylindrical interior wall;
a piston disposed in said first tube member;
a piston rod connected to said piston and extending out from said piston cylinder assembly;
said second tube member being disposed along a substantially common longitudinal axis within said first tube member to form an annular chamber between said exterior wall of said first tube member and said interior wall of said second tube member;
and
a separating piston disposed within said annular chamber and dividing said annular chamber into a first annular chamber portion and a second annular chamber portion;
said separating piston comprising:
a first annular sealing member in sliding and substantially sealing contact with said exterior wall of said first tube member;
a second annular sealing member in sliding and substantially sealing contact with said interior wall of said second tube member;
fluid blocking structure to substantially block passage between said first annular sealing member and said second annular sealing member from said first annular chamber portion to said second annular chamber portion;
and
to provide sufficient relative movement between said first annular sealing member and said second annular sealing member in a direction substantially oblique to said substantially common longitudinal axis to compensate for manufacturing tolerances of one of said first tube member and said second tube member.

10 more elements

Dependencies are inferred from the claim text.