Device for the suspension and for roll-stabilization of motor vehicles

• US 6,604,034 B1
• Filed: 07/05/2001
• Issued: 08/05/2003
• Est. Priority Date: 11/23/1998
• Status: Expired due to Fees

• Current Assignee: Robert Bosch Automotive Steering GmbH (Robert Bosch GmbH)
• Original Assignee: ZF Lenksysteme GmbH (Robert Bosch GmbH)
• Inventors: Gazyakan, Ünal, Speck, Frank-Detlef
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Donnelly, Arthur D.
• Application Number:
  US09/856,668
• Time in Patent Office: 761 Days
• Field of Search: 701/37, 701/38, 280/124.106, 280/5.506, 280/124.1, 280/678, 280/683
• US Class Current: 701/37
• CPC Class Codes: B60G 21/073 between wheels on the same axle but on different sides of the vehicle, i.e. the left and right wheel suspensions being interconnected
• CPC Class Codes: B60G 2202/154 with an accumulator
• CPC Class Codes: B60G 2204/62 Adjustable continuously, e.g. during driving
• CPC Class Codes: B60G 2204/82 left and right unit on same axle
• CPC Class Codes: B60G 2204/8304 using a fluid
• CPC Class Codes: B60G 2500/11 Damping valves
• CPC Class Codes: B60G 2500/20 Spring action or springs
• CPC Class Codes: B60G 2500/32 of only one vehicle part or side
• CPC Class Codes: B60G 2600/21 Self-controlled or adjusted
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/164 Heaving; Squatting

Abstract

A device for the suspension and for roll stabilization of motor vehicles achieves the required roll stiffness as well as the required lift stiffness without any additional springs by coordinating the ratio of the piston areas to the piston ring areas of the spring cylinders with simultaneous active engagement by an actuator integrated between the cross-wired lines.

Claims

1. A device for roll stabilization and suspension of a motor vehicle, the motor vehicle including at least one vehicle wheel, comprising:

an active suspension system acted upon by a pressure medium, each vehicle wheel being connected to a body of the motor vehicle via the active suspension system, the active suspension system including;

a plurality of spring cylinders, piston areas and ring areas of the spring cylinders being configured in a ratio so that additional stabilizers and springs are unnecessary;

lines cross-connecting the spring cylinders via damping elements and hydraulic accumulators provided in the lines; and

an actuator connecting the cross-connected lines.

2. The device according to claim 1, wherein the ratio of piston areas and ring areas is determined in accordance with the following equation:

$\frac{A_K}{A_R}=\frac{2·<br><br>\sqrt{k_W}+s·<br><br>\sqrt{k_H}}{2·<br><br>\sqrt{k_W}-s·<br><br>\sqrt{k_H}},$

wherein A_k represents one of the piston areas, A_R represents a corresponding one of the ring areas, s represents a wheel base, k_W represents a roll stiffness, and k_H represents a lift stiffness.

3. The device according to claim 2, wherein the lift stiffness k_H is determined in accordance with the following equation:

$k_H=2·<br><br>n·<br><br>{\left(A_K-A_R\right)}^2·<br><br>\frac{P}{V},$

wherein P represents a pressure of at least one storage cylinder, V represents a gas volume of the at least one storage cylinder, and n represents a polytropic exponent.

4. The device according to claim 2, wherein the roll stiffness k_W is determined in accordance with the following equation:

$k_W=\frac{1}{2}·<br><br>s^2·<br><br>n·<br><br>{\left(A_K+A_R\right)}^2·<br><br>\frac{P}{V},$

wherein P represents a pressure of at least one storage cylinder, V represents a gas volume of the at least one storage cylinder, and n represents a polytropic exponent.