Patent ID: 7416511

Claim:
A gearshift control system for a hybrid-drive electric vehicle, the vehicle comprises an engine having an output shaft, a transmission having an input shaft and an output shaft, the transmission changing and transmitting a rotation of the input shaft to wheels via the output shaft, the transmission having gear positions including a neutral position and selectively applying one of the gear positions according to a gear shift request, a clutch for connecting and disconnecting power transmission between the output shaft of the engine and the input shaft of the transmission, a rotating electric machine connected to the input shaft of the transmission via gears for operating as an electric motor and an electric generator, a storage element for storing an electric power supplied from the rotating electric machine, the system comprising: determining means for determining whether or not the gear shifting request of the transmission exists; clutch disconnection means for disconnecting the clutch upon the gear shifting request of the transmission; neutral position setting means for changing over the gear position of the transmission to the neutral position when the clutch has been disconnected; mode selecting means for selectively operating the rotating electric machine in a motor mode and in a power generating mode so that a rotational speed of the input shaft of the transmission reaches a region of a synchronizing rotational speed depending on a requested gear position; and gear setting means for setting the gear position of the transmission from the neutral position to the requested gear position, wherein: the gear positions of the transmission include a vehicle-starting gear position; the determining means determines if the gear shifting request is a request to the vehicle-starting gear position, and if the request to the vehicle-starting gear position exists in a vehicle stationary state where the engine is running idle, the transmission is in the neutral position, and the clutch is connected; and when the request to the vehicle-starting gear position exists in the vehicle stationary state, the clutch disconnection means disconnects the clutch, the mode selecting means operates the rotating electric machine in the power generating mode to decrease the rotational speed of the input shaft until the rotational speed of the input shaft reaches the region of the synchronizing rotational speed in the vicinity of a zero value after the clutch means disconnects the clutch, and the gear setting means sets the gear position of the transmission from the neutral position to the vehicle-starting gear position when the rotational speed of the input shaft reaches the region of the synchronizing rotational speed in the vicinity of a zero value.