Vibratory actuator incorporating hydrodynamic journal bearing

A vibratory actuator, which comprises:

• a rigid housing with an inner bearing surface of full cylindrical configuration;
• a rotatable shaft extending longitudinally through said housing;
• an eccentric member secured to said shaft inside said housing for generating vibration responsive to rotation by said shaft;
• said eccentric member including an outer journal surface of partial cylindrical configuration extending in spaced apart relationship with the bearing surface to form a fluid film gap therebetween;
• and
• hydrodynamic fluid disposed in said housing for lubricating rotation of said eccentric member relative to said housing.

Vibratory apparatus for use with a fluid lubricant, comprising:

• a rigid housing with an internal bearing surface of full cylindrical configuration;
• a rotatable shaft extending longitudinally through said housing;
• means for supporting said shaft in opposite ends of said housing;
• and
• an eccentric member secured to said shaft inside said housing for producing vibration upon rotation by said shaft;
• said eccentric member including an external journal surface of arcuate configuration extending in spaced apart relationship with the bearing surface to form a gap therebetween dependent upon the hydrodynamic film thickness of the fluid lubricant in said housing which lubricates rotation of said eccentric member relative to said housing.

In combination with a machine of the type having drive means and an apparatus responsive to vibratory actuation for performing a predetermined function, a vibratory actuator comprising:

• a housing attached to the apparatus, said housing having an inner bearing surface of full cylindrical configuration;
• eccentric means coupled to the drive means and rotatably supported in said housing for generating vibration;
• said eccentric means including an outer journal surface of partial cylindrical configuration extending in spaced apart relationship with the bearing surface of said housing to form a hydrodynamic fluid film gap therebetween;
• and
• fluid disposed in said housing for hydrodynamically supporting said eccentric means during rotation within said housing.