Air spring for a motor vehicle

Patent metadata

Field	Value
Publication number	US-10508704-B2
Application number	US-201615757236-A
Country	US
Kind code	B2
Filing date	Aug 1, 2016
Priority date	Sep 4, 2015
Publication date	Dec 17, 2019
Grant date	Dec 17, 2019

Abstract

An air spring for a motor vehicle having a rolling bellows filled with gas under pressure, one end of the rolling bellows is connected to a load receiver and the other end is fastened to a roll-off piston′. The load receiver and the roll-off piston are moveable relative to one another depending on a force impinging on the load receiver toward the roll-off piston. A sensor device is arranged inside the rolling bellows by which a distance between the load receiver and the roll-off piston is detected. A pressure piece extending in direction of the roll-off piston is arranged at the load receiver and a sensor body is movably drivable along a sensor track of the sensor device by an end region of the pressure piece facing the roll-off piston. The sensor device generates an electric signal corresponding to the position of the sensor body on the sensor track.

First claim

The invention claimed is:

1. An air spring for a motor vehicle comprising:
a load receiver;
a roll-off piston;
a rolling bellows filled with a gas under pressure, a first end of the rolling bellows being connected to the load receiver and a second end of the rolling bellows being fastened to the roll-off piston, wherein the load receiver and the roll-off piston are moveable relative to one another based at least in part on a force impinging on the load receiver toward the roll-off piston;
a sensor device arranged inside the rolling bellows by which a distance between the load receiver and the roll-off piston can be detected and a corresponding electric signal can be generated;
a sensor track of the sensor device;
a pressure piece extending in a direction of the roll-off piston arranged at the load receiver; and
a sensor body configured as a permanent magnet that is movably drivable directly or indirectly along the sensor track of the sensor device by an end region of the pressure piece facing the roll-off piston,
wherein the sensor device generates an electric signal corresponding to a position of the sensor body on the sensor track,
wherein the sensor track is arranged concentric to a rotational axis of a shaft on a sensor track support, and the sensor body is arranged at an end of the shaft remote of the pressure piece.

2. The air spring according to claim 1 , wherein the sensor track is a linearly extending sensor track.

3. The air spring according to claim 1 , wherein the sensor track is a circularly extending sensor track.

4. The air spring according to claim 3 , wherein the pressure piece is fixed with respect to rotation and has at its end area facing the roll-off piston a lock with a lock aperture extending axially to the pressure piece, the shaft configured as an axially stationary shaft of a same cross section which is supported so as to be rotatable around the rotational axis and which has a helical thread extending over a length of the shaft projects into the lock aperture, wherein the sensor body is movably drivable along the circular sensor track from the end of the shaft remote of the pressure piece.

5. The air spring according to claim 1 , wherein the sensor device is a contactless sensor device.

6. The air spring according to claim 1 , wherein the sensor device is a magnetic inductive sensor device.

7. The air spring according to claim 6 , wherein the sensor body has one or more LC circuits, and the sensor track has a first conductor path that extends along the sensor track in a sine-shaped manner and a second conductor path extends along the sensor track in a cosine-shaped manner.

8. The air spring according to claim 7 , wherein the sensor body is movably drivable along a circular sensor track via a gear unit from an end of a shaft remote of the pressure piece.

9. The air spring according to claim 8 , wherein the gear unit is an angular gear unit, and the sensor body is swivelable around a swiveling axis inclined at an angle to a rotational axis of the shaft.

10. The air spring according to claim 8 , wherein the gear unit is a toothed-wheel transmission.

11. The air spring according to claim 10 , wherein an output gear of the toothed-wheel transmission is acted upon in a rotational direction by a spring force which is smaller than the force required for a rotational drive of the toothed-wheel transmission.

12. The air spring according to claim 1 , wherein the electric signal is configured to be fed to control electronics, wherein at least one of an inlet valve and an outlet valve to the interior of the rolling bellows can be controlled by the control electronics.

13. The air spring according to claim 12 , wherein at least one of the control electronics, the inlet valve, and the outlet valve is arranged one of in the roll-off piston and at the roll-off piston.

14. The air spring according to claim 1 , further comprising: a sensor arranged adjoining a contact plug socket, the sensor configured to sense a rotational angle of the permanent magnet and at least indirectly generate a corresponding electric signal and route the signal to plug pins of the contact plug socket.

15. A driver's cab bearing in a motor vehicle comprising:
an air spring for a motor vehicle comprising:
a load receiver;
a roll-off piston;
a rolling bellows filled with a gas under pressure, a first end of the rolling bellows being connected to the load receiver and a second end of the rolling bellows being fastened to the roll-off piston, wherein the load receiver and the roll-off piston are moveable relative to one another based at least in part on a force impinging on the load receiver toward the roll-off piston;
a sensor device arranged inside the rolling bellows by which a distance between the load receiver and the roll-off piston can be detected and a corresponding electric signal can be generated;
a sensor track of the sensor device;
a pressure piece extending in a direction of the roll-off piston arranged at the load receiver; and
a sensor body configured as a permanent magnet that is movably drivable directly or indirectly along the sensor track of the sensor device by an end region of the pressure piece facing the roll-off piston,
wherein the sensor device generates an electric signal corresponding to a position of the sensor body on the sensor track,
wherein the sensor track is arranged concentric to a rotational axis of a shaft on a sensor track support, and the sensor body is arranged at an end of the shaft remote of the pressure piece.

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Nowotka Thomas
• Memmel Alfred
• Memmel Georg

Classifications

• F16F9/057 Primary

  characterised by the piston · CPC title

• F16F9/05

  the flexible wall being of the rolling diaphragm type · CPC title

• B60G2204/111

  on pneumatic springs · CPC title

• B60G17/0521

  the spring having a flexible wall · CPC title

• B60G11/27

  wherein the fluid is a gas · CPC title