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AssigneeZF Friedrichshafen AG
InventorsGeorg GIERER, Christian Popp, Thilo Schmidt, Klaus Steinhauser
Estimating the term…
A method for monitoring frictional engagement in an automatic or automated motor vehicle transmission having a hydrodynamic starter element when the transmission is in a preset neutral or parking position and the automatic or automated motor vehicle transmission controlled by this method. When the motor vehicle is at or close to a standstill in a preset neutral or parking position, the current transmission rotational input speed and a current engine rotational speed of the drive motor are determined and based on the speed ratio between the current transmission rotational input speed and the current engine rotational speed an error is found to be present if the speed ratio is less than a predefined threshold value, which is less than/equal to 1.
1-15. (canceled)
A method of monitoring frictional engagement in one of an automatic motor vehicle transmission and an automated motor vehicle transmission having a hydrodynamic starter element and being in a preset neutral position and a parking position, and the transmission being connected to a drive motor of the motor vehicle via the hydrodynamic starter element, the method comprising the steps of:
A motor vehicle transmission comprising a hydrodynamic starter element arranged, in a power flow direction, between a drive motor and the motor vehicle transmission, the hydrodynamic starter element being engaged for transmitting drive motor rotational speed into transmission rotational input speed, and an electronic control device to control the motor vehicle transmission, a speed ratio of the transmission rotational input speed to the engine rotational speed is calculated when the motor vehicle transmission is in one of a preset neutral position and a parking position and the motor vehicle is one of at and close to a standstill, and an error is present in the transmission if the speed ratio of the transmission rotational input speed to the engine rotational speed is less than a preset threshold value which is one of less than and equal to 1.
Dependencies are inferred from the claim text.