Vibrating device

A vibrating apparatus comprising:

• a housing;
• a rotatable first shaft supported by and located in said housing;
• a first and a second mass, said respective masses being rotatable in phase within said housing to cause said device to vibrate, first means mounting each of the masses on said first shaft and being disposed radially from the axis of said first shaft, said first means being defined by an arm fixed to said first shaft, said arm having radially opposite first and second sections, said sections extending radially from said first shaft in opposite directions;
• a second shaft, said second shaft rotatably attached to said first mass and to a radially outer portion of said second section, whereby, the center of gravity of said first mass is radially spaced from the axis of said second shaft;
• a third shaft, said third shaft being adapted to rotatably attach said second mass to a radially outer portion of the first section to said second section for permitting the center of gravity of said second mass to be radially spaced from the axis of said third shaft;
• and second means to rotate said second mass about the axis of said third shaft in phase with said first mass, when said arm is rotated relative to said housing.