Dynamometer for simulating the inertial and road load forces encountered by motor vehicles

A dynamometer for simulating the inertia and road load for motor vehicles comprising:

• a stationary frame;
• a moveable frame pivotally mounted on the stationary frame about a lateral axis;
• at least one roll adapted to engage at least one vehicle wheel which is powered by the vehicle's motor, the roll being rotatably mounted on the moveable frame about a lateral axis, the lateral axis being parallel to the axis of rotation of the wheel;
• a power supplying and/or absorbing unit secured to the moveable frame;
• means for coupling the power supplying and/or absorbing unit to the roll, the power supplying and/or absorbing unit being arranged to supply power to and/or absorb power from the roll, the roll applying force to or receiving a force from the wheel in accordance with the supplied or absorbed power;
• transducing means coupled between the moveable and stationary frames at a location spaced from the lateral axis for providing a measure of the force applied to or received from the vehicle wheel by the roll, the measured force including the force necessary to compensate for the force associated with the parasitic losses of the rotating roll, the power supplying and/or absorbing unit and the coupling means;
• speed sensing means for providing a measure of the vehicle wheel speed;
• and
• control means responsive to the vehicle wheel speed and the force applied to or received from the vehicle wheel for controlling the power supplying and/or absorbing unit to supply power to and/or absorb power from the roll so that the force applied to or received from the wheel is proportional to the force associated with a selected simulated inertia and road load for the vehicle.

A dynamometer for simulating the inertia and road load for motor vehicles comprising:

• a stationary frame;
• a pair of spaced rolls, each roll being adapted to engage one of the driven wheels of the vehicle;
• a shaft interconnecting the rolls to provide synchronous rotation thereof;
• a movable frame having a longitudinal axis lying in a plane which bisects the shaft at right angles, the shaft being rotatably mounted on the moveable frame about a lateral axis;
• an electric motor supported on the moveable frame on one side of the shaft and connected to the shaft for supplying power to or absorbing power from the shaft;
• the moveable frame being pivotably mounted on the stationary frame about the lateral axis;
• force sensing means coupled between the moveable frame and the stationary frame and spaced from the shaft for providing a measure of the force applied to or received from the vehicle wheels by the rolls and a measure of the force associated with the parasitic losses of the rotating components of the dynamometer;
• speed sensing means coupled to the rolls for providing a measure of the vehicle wheel speed;
• and
• control means responsive to the vehicle wheel speed and the force applied to or received from the vehicle wheels for controlling the motor to supply power to or absorb power from the rolls so that the force applied to or received from the wheels is proportional to a selected inertia and road load for the vehicle being tested.

A dynamometer for simulating the inertia and road load forces for a vehicle comprising:

• at least one roll adapted to engage a driven wheel of the vehicle;
• a power supplying and/or absorbing unit;
• means for coupling the power supplying and/or absorbing unit to the roll;
• force measuring means for providing a measure of the force applied to or received from the roll by the vehicle wheel plus the force associated with the parasitic losses of the rotating roll, the power supplying and/or absorbing unit and the coupling means;
• velocity sensing means for providing a measure of the roll speed;
• and
• control means responsive to the roll speed and the force measured by the force sensing means for controlling the power supplying and/or absorbing unit to supply power to or absorb power from the roll so that the force applied to or received from the wheel by the roll is proportional to a force associated with a selected inertia and road load for the vehicle.