Clutch parameters
AssigneeSchaeffler Technologies AG & Co. KG
InventorErhard Hodrus
Life of this patent
Estimating the term…
Abstract
A method of determining clutch parameters at the initial start of operation of a friction clutch in a motor vehicle comprising the steps of: in a first phase, moving the clutch from an open state into a closed state and into an open state again at a predetermined constant slip of the clutch and determining and storing the position of the clutch during the movement when predetermined clutch torque thresholds are reached; in a second phase, in a first step, determining a touch point, a position hysteresis, and a torque hysteresis from the determined positions; determining a preliminary friction coefficient; determining preliminary form factors; determining a final friction coefficient; and determining final form factors.
Claims13
A method of determining clutch parameters at an initial start of operation of a friction clutch in a motor vehicle comprising the steps of:
- in a first phase:
- moving, using a control unit, the clutch from an open state into a closed state and into the open state again at a predetermined constant slip of the clutch;
- and
- determining and storing, using the control unit, a position of the clutch during the movement when predetermined clutch torque thresholds are reached;
- in a second phase, in a first step, determining, using the control unit, a touch point, a position hysteresis, and a torque hysteresis from the determined position;
- determining, using the control unit, a preliminary friction coefficient;
- determining, using the control unit, preliminary form factors;
- determining, using the control unit, a final friction coefficient;
- and,
- determining, using the control unit, final form factors.
A device including a control device for determining clutch parameters at an initial start of operation of a friction clutch in a motor vehicle, the control device arranged to:
- in a first phase, move the clutch from an open state to a closed state and back to the open state at a predetermined, constant slip of the clutch when a torque is transmitted and, during the movement, to determine and store a position of the clutch when a predetermined clutch torque threshold is reached;
- in a second phase, determine:
- a touch point;
- a position hysteresis using a parallel displacement of a modified nominal characteristic curve in a direction of the position as a function of a speed of a clutch actuator;
- and
- a torque hysteresis from the determined position;
- determine a preliminary friction coefficient;
- determine preliminary form factors;
- determine a final friction coefficient;
- and
- determine final form factors.
A device including a control device for determining clutch parameters at an initial start of operation of a friction clutch in a motor vehicle, the control device arranged to:
- in a first phase, move the clutch from an open state to a closed state and back to the open state at a predetermined, constant slip of the clutch when a torque is transmitted and, during the movement, to determine and store a position of the clutch when a predetermined clutch torque threshold is reached;
- in a second phase, determine:
- a touch point;
- a position hysteresis;
- and
- a torque hysteresis from the determined position by superimposing a torque-dependent scaling to a parallel displacement of a modified nominal characteristic curve in a direction of the position;
- determine a preliminary friction coefficient;
- determine preliminary form factors;
- determine a final friction coefficient;
- and
- determine final form factors.
Dependencies are inferred from the claim text.