Method for operating a multi-axle drive train for a motor vehicle, and corresponding multi-axle drive train

• US 10,195,939 B2
• Filed: 11/05/2015
• Issued: 02/05/2019
• Est. Priority Date: 11/06/2014
• Status: Active Grant

• Current Assignee: Audi AG (Volkswagen AG)
• Original Assignee: Audi AG (Volkswagen AG)
• Inventors: Weidemann, Dieter, Hanickel, Heiko, Kolb, Florian, Bruhl, Hans Jorg
• Primary Examiner(s): Knutson, Jacob D
• Application Number:
  US15/523,959
• Publication Number:
  US 20170313187A1
• Time in Patent Office: 1,188 Days
• Field of Search: 180247
• CPC Class Codes: B60K 17/352 manually operated
• CPC Class Codes: B60K 2023/0833 for adding torque to the rear wheels
• CPC Class Codes: B60K 2023/0841 for locking a central differential, e.g. by using a lock-up clutch
• CPC Class Codes: B60K 2023/0858 with electric means, e.g. electro-hydraulic means
• CPC Class Codes: B60K 2023/0883 manually actuated
• CPC Class Codes: B60K 23/08 for changing number of driven wheels , for switching from driving one axle to driving two or more axles B60K17/3515 takes precedence
• CPC Class Codes: B60Y 2306/09 Reducing noise
• CPC Class Codes: B60Y 2400/421 Dog type clutches or brakes

Abstract

A device and a method for operating a multi-axle drive train for a motor vehicle. A first axle and a second axle are operatively connected, at least temporarily, to a drive device. When the second axle is decoupled from the drive device and a request for multi-axle drive with a first value is present, the second axle is coupled to the drive device only when a noise-masking event occurs, or when the second axle is coupled to the drive device and the request for multi-axle drive is absent, the second axle is decoupled from the drive device only when the noise-masking event occurs.

Claims

1. A method for operating a multi-axle drive train for a motor vehicle, comprising:

providing a first axle and a second axle being operatively connected at least temporarily to a drive device, wherein, when the second axle is decoupled from the drive device and a request for multi-axle drive with a first value is present, the second axle is coupled to the drive device only when a noise-masking event occurs, and when the second axle is coupled to the drive device and the request for multi-axle drive is absent, the second axle is decoupled from the drive device only when the noise-masking event occurs.

2. The method according to claim 1, wherein the coupling of the second axle to the drive device and the decoupling of the second axle from the drive device will be delayed until the noise-masking event is present.

3. The method according to claim 1, wherein the noise-masking event is at least one of an operating state of the motor vehicle, a change in the operating state of the motor vehicle, an operation of the driver, and an environmental influence.

4. The method according to claim 1, wherein the request for multi-axle drive is pre-controlled, having been determined from at least one operating variable of the multi-axle drive train.

5. The method according to claim 4, wherein a travel speed, an acceleration, an inclination of the ground, and a state variable of a drive device is used as the at least one operating variable.

6. The method according to claim 1, wherein when the request for multi-axle drive with a second value is present, the second axle is immediately coupled to the drive device.

7. The method according to claim 6, wherein the request for multi-axle drive is set at the second value when a slippage is established, and slippage is to be expected based on an operating variable, and an increase in drive power is requested.