Mining machine with multiple cutter heads

A mining machine comprising:

• a frame;
• a boom supported for pivoting movement relative to the frame;
• a cutter head supported on the boom, the cutter head including,
• a housing pivotably coupled to the boom,
• a cutter shaft coupled to the housing and secured against rotation about a longitudinal axis of the cutter shaft, the shaft including a first end, a second end, a first portion positioned adjacent the first end and a second portion positioned adjacent the second end, the second portion extending parallel to a cutter axis,
• a cutting disc coupled to the second portion of the cutter shaft and supported for free rotation relative to the cutter shaft about the cutter axis, the cutting disc including a plurality of cutting bits defining a cutting edge, and
• an excitation mechanism including an exciter shaft and an eccentric mass supported on the exciter shaft for rotation about an exciter axis, the exciter shaft driven for rotation relative to the cutter shaft about an exciter axis, rotation of the exciter shaft inducing oscillating movement of the second portion of the cutter shaft and the cutting disc.