Drive force transmission apparatus

A drive force transmission apparatus that is configured to transmit a drive force from first and second drive sources to a drive device of a vehicle, which drives the vehicle, the drive force transmission apparatus comprising:

• a first main shaft that has one end portion, which is connected to the first drive source;
• a second main shaft that has one end portion, which is connected to the second drive source, wherein the second main shaft is generally coaxial with the first main shaft, and the other end portion of the second main shaft, which is opposite from the one end portion of the second main shaft, is opposed to the other end portion of the first main shaft, which is opposite from the one end portion of the first main shaft;
• a countershaft that has one end portion, which is connected to the drive device, wherein the countershaft is generally parallel to the first main shaft and the second main shaft;
• a first drive gear that is provided at one of the first main shaft and the second main shaft;
• a second drive gear that is connected to the other one of the first main shaft and the second main shaft;
• a first secondary coupling portion that is provided at one of the other end portion of the first main shaft and the other end portion of the second main shaft;
• a first primary coupling portion that is provided at the other one of the other end portion of the first main shaft and the other end portion of the second main shaft, wherein the first primary coupling portion is engageable with the first secondary coupling portion to connect between the first main shaft and the second main shaft;
• a first tubular shaft that is placed on a radially outer side of the countershaft, wherein the first tubular shaft is generally coaxial with the countershaft and is rotatable relative to the countershaft;
• a second tubular shaft that is placed on a radially outer side of the first tubular shaft, wherein the second tubular shaft is generally coaxial with the first tubular shaft and is rotatable relative to the first tubular shaft;
• a first driven gear that is provided at one end portion of the first tubular shaft and is meshed with the first drive gear;
• a second driven gear that is provided at one end portion of the second tubular shaft and is meshed with the second drive gear;
• a second secondary coupling portion that is provided at the countershaft;
• a second primary coupling portion that is provided at the other end portion of the first tubular shaft, which is opposite from the one end portion of the first tubular shaft, wherein the second primary coupling portion is engageable with the second secondary coupling portion to connect between the first tubular shaft and the countershaft;
• and
• a third primary coupling portion that is provided at the other end portion of the second tubular shaft, which is opposite from the one end portion of the second tubular shaft, wherein the third primary coupling portion is engageable with the second secondary coupling portion to connect between the second tubular shaft and the countershaft.