Method for operating a transmission device with a plurality of friction-locking and positive-locking shifting elements

Abstract

A method is described for operating a transmission device (1) with a plurality of friction-locking and positive-locking shifting elements (A to F) for obtaining different gears. A shift request to close a positive-locking shifting element (F) undergoes a time delay dependent on operational state prior to the connection time of the positive-locking shifting element, wherein a rotational speed differential between the halves of the shifting element of the positive-locking shifting element (F) is provided for the connection time within a rotational speed differential window required for the engagement. According to the invention, a gradient of the transmission input speed or an equivalent rotational speed value is detected at the time of the shift request and the actual gradient is subsequently monitored and also compared to the gradients at the time of the shift request. When a maximum deviation greater than a threshold value is detected, the period of time is changed or an actuation of a friction-locking shifting element to be disconnected is varied to an extent that reduces the deviation below the threshold value.

Description

technical field [0001] The invention relates to a method for operating a transmission arrangement comprising a plurality of friction-locking shifting elements and positive-locking shifting elements according to the type further defined in the preamble of claim 1 . Background technique [0002] In automatic transmissions known from practice that have both friction-fitting and form-fitting shifting elements to obtain a plurality of different gear ratios, the shifting mechanism for closing the form-fitting connection by means of the application of force The gear command is triggered by means of the transmission control unit or the transmission software running in the transmission control unit with a certain time advance before the synchronization point of the form-fitting shifting elements is reached. [0003] The timing advance is also largely influenced by the operating temperature of the transmission oil, especially in the case of hydraulically actuated form-locking shifting...

AI Technical Summary

Problems solved by technology

[0007] However, the problem with the above-mentioned transmission device is that the spontaneous gradient of the transmission input speed or the equivalent speed variable cannot be taken into account to the desired extent after the moment of the shift request of the shifting element for engaging the positive lock. change, such as a spontaneous change caused, for example, by a sharp change in the position of the vehicle's accelerator pedal or by heavy braking of the vehicle on the driver's side

If the engagement of the form-fitting shifting elements is carried out outside the desired speed difference range, shifting noises occur which reduce driving comfort and the driver also experiences a torque reaction in the form of jerks in the drivetrain

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