Patent attributes
An engine system comprising: a housing having an accommodating cavity; a crankshaft part, a speed change mechanism and a transmission shaft are provided in the accommodating cavity; and a first motor and a second motor are located outside the accommodating cavity and provided on the housing. The crankshaft part is provided in the accommodating cavity and outputs first power. The first motor comprises a first motor shaft which is connected to an output end of the crankshaft part to convert the first power into electric energy. The second motor comprises a second motor shaft and is configured to output second power according to electric energy. The speed change mechanism is drivingly connected to the second motor shaft without connecting the output end of the crankshaft part. The transmission shaft is connected to an output end of the speed change mechanism. Also disclosed is an all-terrain vehicle.