Force and moment canceling reciprocating mechanism and power tool having same

A reciprocating tool, comprising:

• a housing;
• a motor received in the housing;
• a reciprocating mechanism reciprocally coupled in the housing and configured to reciprocate along a first axis of operation;
• and
• a transmission received in the housing, wherein the transmission includes:
• a counterweighted input gear assembly engaged with an output shaft of the motor, the output shaft being arranged in parallel with the first axis of operation, including:
• a first shaft aligned with a second axis of operation that is substantially orthogonal to the first axis of operation;
• a first input gear arranged on the first shaft;
• and
• a second input gear arranged on the first shaft such that the first input gear, the first shaft and the second input gear are concentrically arranged;
• and
• a counterweighted output gear assembly engaged with the counterweighted input gear assembly, and engaged with the reciprocating mechanism, so as to transfer a force generated by the motor to the reciprocating mechanism, the counterweighted output gear assembly including:
• a second shaft arranged in parallel with the second axis of operation;
• a first output gear arranged on the second shaft;
• and
• a second output gear arranged on the second shaft such that the first output gear, the second shaft and the second output gear are concentrically arranged, wherein the counterweighted input gear assembly and the counterweighted output gear assembly are configured to operate to dynamically balance forces generated about the first axis of operation and the second axis of operation,
• the reciprocating mechanism being configured to convert a rotational force, generated by the motor and transferred thereto by the transmission, to a reciprocating linear force output by the reciprocating mechanism.