US 2002/0119857 A1 · Controllable torque transfer differential mechanism using magnetorheological fluid

Abstract

A method of controlling torque transfer from a torque input source to an outlet source in which an electronically controllable magnetorheological fluid-based torque limiting device is coupled to either a differential pinion gear, a side gear, both the differential pinion gear and side gear, or both side gears of a differential assembly. By introducing current through electronically controllable magnetorheological fluid-based torque-limiting device during a turning or spin-out condition, and thereby increasing the viscosity of the magnetorheological fluid within the torque limiting device, the amount of torque that is transferred to the output source through the differential assembly can be controlled.

Claims20

Dependent claims

A torque transfer control system comprising:

a torque supply source;
a differential coupled to said torque supply source;
an output source coupled to said differential;
and
an activatable magnetorheological-based torque limiting device coupled to said differential, wherein said activatable magnetorheological-based torque limiting device limits the transfer of torque from said torque supply source to said output source when activated.

2 more elements

A method for controlling torque transfer from a torque supply source to an outlet source in a drive system, the method comprising the steps of:

coupling a differential assembly to the torque supply source and to the outlet source;
coupling an electronically controllable magnetorheological fluid-based torque-limiting device to said differential;
electronically activating said electronically controllable magnetorheological fluid-based torque limiting device during a turning condition or to prevent a spin-out condition to change a phase of a quantity of magnetorheological fluid contained within said electronically controllable magnetorheological fluid-based torque limiting device from a free flowing liquid to a semi-solid state, wherein said change of phase causes a decrease in the rotational speed of the outlet source relative to the rotational speed of the torque supply source.

A method for controlling torque transfer from an input source to a wheel assembly through a differential assembly during a turning or to prevent a spin-out condition, the method comprising the steps of:

coupling an electronically controllable magnetorheological fluid-based closed pump system having an electronic control unit to a first component of the differential assembly;
and
controlling the rotation of a first component of the differential assembly by activating said electronically controllable magnetorheological fluid-based closed pump system.

Dependencies are inferred from the claim text.

Facts

Application

09/791,478Filed 23 Feb 2001

Published

29 Aug 2002

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

F16H 48/30
Arrangements for suppressing or influencing the differential action, e.g. locking devices: using externally-actuatable means
F16H 48/26
Arrangements for suppressing or influencing the differential action, e.g. locking devices: using fluid action, e.g. viscous clutches
F16H 48/34
Using externally-actuatable means: using electromagnetic or electric actuators
F16H 2048/204
Arrangements for suppressing or influencing the differential action, e.g. locking devices: control of arrangements for suppressing differential…

Controllable torque transfer differential mechanism using magnetorheological fluid

Life of this patent

Controllable torque transfer differential mechanism using magnetorheological fluid

Life of this patent

Abstract

Claims20