Vehicle mounted dynamometer and method

Claim 1

The combination of a dynamometer and an engine assembly, the engine assembly including a rigid frame, an engine and a drive shaft, said engine mounted by compressible engine mounts to a rigid frame, the engine adapted to rotate a drive shaft, the dynamometer comprising a linear variable differential transformer mounted to the rigid frame and having an input, an output and a displaceable permeable core in contact with and deflected by the engine for varying the magnetic coupling between said input and said output in response to torquing of the engine, means for applying a voltage to said linear variable differential transformer input whereby a torque output signal is formed on said linear variable differential transformer output proportional to the torque output of the engine, a relative horsepower reading meter having a meter input, switching means having an input and an output, said switching means input being coupled to said linear variable differential transformer output, said switching means being actuated by rotation of the drive shaft such that the amount of time said switching means is closed is directly proportional to the angular velocity or frequency of rotation of the drive shaft whereby a horsepower signal is generated on said switching means output having a magnitude proportional to the torque output of the engine and having a repetition rate proportional to the rotation frequency of the drive shaft, and coupling means for coupling said horsepower signal on said switching means output to said meter input.