US 5,669,597 AGranted

Self-pumping air suspension spring mounted on a shock absorber assembly

AssigneeFichtel & Sachs AG

InventorsHenning Rittstieg, Hartmut Rolleke

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Abstract

Self-pumping air suspension spring for a motor vehicle, comprising a roller bellows, which form a spring chamber, a spring carrier which consists of a cylinder and a piston rod (which piston rod can move axially in the cylinder, whereby the roller bellows are functionally connected to the cylinder and the piston rod), a vestibule with at least one connection to the spring chamber and at least one connection to the air reservoir, which can be of any appropriate type. In the event of a movement of the piston rod, there is a pumping action via the vestibule in connection with at least one non-return valve in the spring chamber, whereby the vestibule is located inside the spring chamber enclosed by the roller bellows and the cylinder. At least one of the components of the air suspension spring executing the pumping action is formed by the piston rod. It is appropriate if the cylinder is used in conjunction with a vibration damper which is part of an air suspension spring.

Claims20

Dependent claims

Self-pumping air suspension spring for a motor vehicle, comprising roller bellows which form a spring chamber, a spring carrier which comprises a cylinder and a piston rod which can be displaced axially in the cylinder, whereby the roller bellows are functionally connected to the cylinder and the piston rod, a compressed air reservoir, a vestibule with at least one connection to the spring chamber and at least one connection to the compressed air reservoir, whereby when there is a movement of the piston rod a pumping process into the spring chamber takes place via the vestibule in connection with at least one non-return valve, characterized by the fact that the vestibule is located inside the spring chamber which is enclosed by the roller bellows and the cylinder, whereby at least one of the components of the air suspension spring which performs the pumping process is formed by the piston rod, the vestibule is formed by a tube which has a first bottom which is functionally connected to the piston rod, and a second bottom which is functionally connected to the cylinder, whereby inside the at least partly hollow piston rod there is a flow connection with the air reservoir which emerges in the vestibule, whereby the vestibule is reduced in size when the piston rod executes an insertion movement, and the excess compressed air escapes into the spring chamber by means of a non-return valve, the non-return valve between the vestibule and the spring chamber is an elastically expandable ring which covers an overflow opening in the tube.

Self-pumping air suspension spring for a motor vehicle, comprising roller bellows which form a spring chamber, a portion of the roller bellows comprising a wall, a spring carrier which comprises a cylinder and a piston rod which can be displaced axially in the cylinder, whereby the roller bellows are functionally connected to the cylinder and the piston rod, a compressed air reservoir, a vestibule with at least one connection to the spring chamber and at least one connection to the compressed air reservoir, whereby when there is a movement of the piston rod a pumping process into the spring chamber takes place via the vestibule in connection with at least one non-return valve, characterized by the fact that the vestibule is located inside the spring chamber which is enclosed by the roller bellows and the cylinder, whereby at least one of the components of the air suspension spring which performs the pumping process is formed by the piston rod, the pumping process is performed by a partly-elastic membrane which surrounds the piston rod, whereby the membrane is firmly clamped on one of its limiting edges and on the other limiting edge is in contact with a second portion of the roller bellows, and together with the wall forms the vestibule, which functionally corresponds to the part which firmly clamps the limiting edge, whereby as a result of the movement of the part with which the limiting edge of the membrane is in contact and the fixed position of the other limiting edge, increases or decreases the size of the vestibule by means of a shielding movement of the membrane, so that an overpressure or an underpressure is established alternately in the vestibule.

A self-pumping air suspension spring for a motor vehicle, said air-suspension spring comprising:

a spring carrier;
said spring carrier comprising:
a cylinder, said cylinder having a longitudinal axis;
a piston rod which can be displaced axially within said cylinder;
and
said piston rod comprising a hollow portion;
an air bellows;
said air bellows being disposed to form a spring chamber;
said spring chamber being enclosed by said air bellows and said cylinder;
said air bellows being operatively connected to said cylinder and said piston rod to provide self-pumping of said air suspension spring;
a tube disposed within said spring chamber;
a second chamber disposed within said tube;
said tube having a first end and a second end;
said tube being disposed to receive compressed air;
said first end of said tube being fixedly connected to said piston rod;
at least one flow connection from said second chamber to said spring chamber;
means for providing compressed air;
at least one connection to said means for supplying compressed air;
at least one non-return valve;
and
said at least one non-return valve being disposed between said second chamber and said spring chamber to permit flow of compressed air from said second chamber into said spring chamber upon a decrease in size of said second chamber during operation of said air suspension spring.

18 more elements

Dependencies are inferred from the claim text.