Electric motor driven vehicle and power unit thereof

An electric motor driven bicycle comprising:

• a vehicle body including front, central, and rear frame portions extending along a longitudinal axis of said vehicle body and a drive wheel, having a drive wheel axis, coupled to said rear frame portion substantially planar to said longitudinal axis;
• an electric motor, fixably mounted to said rear frame portion along a first side of said longitudinal axis and coupled to an external control means and battery supply, for driving a rotary shaft;
• and
• drive means, contained in a single unitary housing pivotally connected to said rear frame portion along a second side of said longitudinal axis opposite that of said first side and operatively connected to said drive wheel, for driving said drive wheel, said drive means comprising
• a final reducing gear, operatively coupled to said drive wheel, for rotating said drive wheel, and
• a belt type stepless speed change transmission, operatively coupling said rotary shaft to said final reducing gear, for rotatably driving said final reducing gear.

An electric motor driven bicycle comprising:

• a vehicle body including front, central, and rear frame portions and a drive wheel, having a drive wheel axis, coupled to said rear frame portion;
• and
• a drive system contained in a single unitary housing coupled to said central frame portion by a plate connector, said rear frame portion by a spring member, and said drive wheel, said drive system comprising
• an electric motor, coupled to external control means and battery supply, driving a rotary shaft,
• a final reducing gear operatively coupled to and rotating a drive wheel of the electric motor driven bicycle, and
• a stepless speed change transmission, operatively coupling said rotary shaft to and driving said final reducing gear,
• said drive means implemented so that said electric motor is positioned above said drive wheel axis, and
• said battery supply being housed within a battery housing space located under a step floor of said central frame portion to lower the center of gravity of the electric motor driven bicycle, said battery supply accessible through said step floor which is a lid of said battery housing space.

An electric motor driven bicycle comprising:

• a vehicle body including front, central, and rear frame portions and a drive wheel, having a drive wheel axis, coupled to said rear frame portion;
• a drive system contained in a single unitary housing, coupled to said central frame portion and said drive wheel, comprising
• an electric motor, coupled to an external control means and battery supply, driving a rotary shaft,
• a final reducing gear operatively coupled to and rotating a drive wheel of the electric motor driven bicycle, and
• a belt type stepless speed change transmission, operatively coupling said rotary shaft to and driving said final reducing gear;
• and
• a magnetically shielded user utilizable vehicle storage compartment.

An electric motor driven bicycle comprising:

• a vehicle body including front, central, and rear frame portions extending along a longitudinal axis of said vehicle body and a drive wheel, having a drive wheel axis, coupled to said rear frame portion substantially planar to said longitudinal axis;
• an electric motor, fixably mounted to said rear frame portion along a first side of said longitudinal axis and coupled to an external control means and battery supply, for driving a rotary shaft;
• and
• drive means, contained in a single unitary housing pivotally connected to said rear frame portion along a second side of said longitudinal axis opposite that of said first side and operatively connected to said drive wheel, for driving said drive wheel, said drive means comprising
• a final reducing gear, operatively coupled to said drive wheel, for rotating said drive wheel, and
• a stepless speed change transmission, operatively coupling said rotary shaft to said final reducing gear, for rotatably driving said final reducing gear,
• said rear frame being pivotally coupled to said single unitary housing through a pair of supporting swing arms along said second side and being coupled to a support plate of said electric motor along said first side, said pair of supporting swing arms being pivotable along a central axis of said rotary shaft.

A drive system for an electric motor vehicle comprising:

• an electric motor;
• a driving wheel;
• a speed change transmission for an electric motor vehicle comprising:
• an electric motor;
• a driving wheel;
• a speed change transmission for transmitting the rotation of said electric motor to said driving wheel to run the vehicle, said speed change transmission maintaining motor speed within a range preselected to be within a desired percentage of maximum motor efficiency;
• and
• a centrifugal clutch located between said electric motor and speed change transmission.