US 12,343,761 B2
Systems and methods for producing a pure vibration force from a synchronized dual array of eccentric rotating masses
Michael G. Snow, Erie, CO (US); Nikhil Bajaj, West Lafayette, IN (US); and John Houston, San Francisco, CA (US)
Assigned to General Vibration Corporation, San Francisco, CA (US)
Filed by General Vibration Corporation, San Francisco, CA (US)
Filed on May 18, 2022, as Appl. No. 17/747,097.
Application 17/747,097 is a continuation of application No. PCT/US2020/061554, filed on Nov. 20, 2020.
Claims priority of provisional application 62/938,363, filed on Nov. 21, 2019.
Prior Publication US 2022/0395861 A1, Dec. 15, 2022
Int. Cl. A63F 13/285 (2014.01); B06B 1/04 (2006.01); B06B 1/16 (2006.01)
CPC B06B 1/166 (2013.01) [B06B 1/045 (2013.01); A63F 13/285 (2014.09)] 22 Claims
OG exemplary drawing
 
1. At least one attachment for a rotatable shaft of a vibration motor, the vibration motor having a motor case and the rotatable shaft coupled to the motor case, the rotatable shaft extending outwards beyond the motor case and having an axis of rotation therealong, the at least one attachment comprising:
a first region configured to be affixed to the rotatable shaft, the first region having a first mass portion, a first center of mass, a first radius, and a first eccentricity, the first radius being defined as the shortest distance between the first center of mass and the axis of rotation, and the first eccentricity being defined as the first radius multiplied by the first mass portion; and
a second region configured to be affixed to the rotatable shaft, the second region having a second mass portion, a second center of mass, a second radius, and a second eccentricity, the second radius being defined as the shortest distance between the second center of mass and the axis of rotation, and the second eccentricity being defined as the second radius multiplied by the second mass portion;
wherein:
a normal projection of the first center of mass onto the axis of rotation is at a first point Pp1;
a normal projection of the second center of mass onto the axis of rotation is at a second point Ps1;
Pp1 and Ps1 are different points;
the rotatable shaft having its center of mass located on the axis of rotation;
the second region is distinct from the first region;
an imaginary line passes through the first region and the second region and intersects the axis of rotation; and
the first eccentricity>the second eccentricity>0.