Patent ID: 9322237
Filing Date: 2016-04-26
CPC Classification: E21B

Claim Text:
1. Apparatus to operate as a mechanical force generator with an at least near sinusoidal output or as a mechanical excitation device with an at least near sinusoidal output, the apparatus having a longitudinal axis and comprising or including: an elongate inner member axially aligned to the longitudinal axis, a mass disposed about the inner member and able to reciprocate relative thereto in the longitudinal direction, an outer member about at least part of the mass and about at least part of the inner member and in respect of which the mass can move axially in the longitudinal direction yet is constrained from any substantial rotation relative to the outer member about the longitudinal axis, a rotatable member able to rotate about the longitudinal axis and directly and/or indirectly upon its rotation to cause axial reciprocation of the mass relative to said outer member, and a rotary drive to provide directly or indirectly a rotational input to the rotatable member; wherein without impacts or impacts of significance there is an output pathway from the mass into the outer member.