Method for performing gear shifting

1. Method for performing gear shifting by engaging a coupling element with a gear wheel, wherein the gear wheel is adapted to be locked to an input shaft with the aid of the coupling element in order to transmit power from the input shaft to an output shaft, comprising

moving the coupling element relative to the gear wheel from a disengaged position to an engaged position, in which a particular gear is selected,

controlling a rotational speed of the coupling element relative to a rotational speed of the gear wheel by a synchronizing arrangement, the synchronizing arrangement comprising a first synchronizing gear wheel which is rotationally locked to the input shaft, and a second synchronizing gear wheel which is in mesh with the first synchronizing gear wheel, and a synchronizer unit operatively arranged between the output shaft and the second synchronizing gear wheel, wherein the synchronizer gear wheels are designed so that a desired, predetermined speed difference between the input shaft and the gear wheel is achieved when the synchronizer unit is in an engaged state, and

controlling a rotational speed of the coupling element during movement of the coupling element so that the speed difference is maintained until the coupling element reaches the engaged position.

2. A method according to claim 1 , comprising continuously controlling the speed difference so that it is maintained irrespective of any collision between engagement means of the coupling element and the gear wheel until the coupling element reaches the engaged position.

3. A method according to claim 1 comprising moving the coupling element relative to a shaft on which the coupling element is disposed in a rotationally locked manner.

4. A method according to claim 1 , comprising ceasing the controlled speed difference between the coupling element and the gear wheel when the engaged position is reached.

5. A method according to claim 1 , comprising transmitting the maintained speed difference from the coupling element and the gear wheel to a synchronizer unit when the engaged position is reached.

6. A method according to claim 5 , comprising permitting slippage between two engaging force transmitting elements in the synchronizer unit.

7. A method according to claim 1 , comprising sensing a relative position of the coupling element and the gear wheel for detecting when the engaged position is reached.

8. A method according to claim 1 , comprising establishing a signal when the engaged position is reached.

9. A non-transitory computer readable medium comprising a computer program for implementing the method as claimed in claim 1 when the program is run on a computer.

10. A computer program product comprising computer program segments stored on a computer-readable means for implementing the method as claimed in claim 1 when the program is run on a computer.

11. A gear shifting arrangement, comprising

two parallel transmission shafts in the form of an input shaft and an output shaft,

a first gear wheel, the first gear wheel being axially locked to and freely rotatably mounted on the input shaft when the first gear wheel is not used to transfer engine power from the input shaft,

a second gear wheel, the first gear wheel being further in mesh with the second gear wheel, the second gear wheel being rotationally locked on the output shaft,

a synchronizing arrangement arranged to synchronize a speed of the input shall relative to a speed of the output shaft during gear shifting, the synchronizing arrangement comprising a synchronizing unit, a first synchronizing gear wheel that is rotationally locked to the input shaft, and a second synchronizing gear wheel that is in mesh with the first synchronizing gear wheel,

wherein the synchronizer gear wheels are designed so that a desired, predetermined speed difference between the input shaft and the first gear wheel is achieved when the synchronizer unit is in an engaged state.