Toroidal transmission

Abstract

A method is provided for optimally engineering a toroidal transmission having a desired input/output ratio to implement the desired ratio of the transmission while meeting the torque and efficiency requirements of the design. Nanoparticle technology is used to manufacture the stator walls to replace the cutting and milling procedures now in use. A novel Mitchell bearing sleeve and its particular hydrodynamic lubrication and cooling method are proposed herein, as well as the introduction of a novel, ultra smooth, amorphous non-oxidizing contact sleeve material used to form the contact sleeve of the drive rollers. A novel self-lubricating system is further provided that includes an oil reservoir disposed within an output shaft of the transmission.

1 . A toroidal transmission comprising: 
 a housing defining a plurality of helical stator races that define a toroidal cavity;    a yoke disposed within the housing being fixedly attachable to a shaft;    a plurality of rotor units attachable to the yoke, each rotor unit having a plurality of drive rollers, each drive roller being rotatably supported on a mounting pin of a rotor unit arm, the plurality of drive rollers being configured to be in simultaneous rolling engagement with the stator races and a worm race; and    an oil reservoir disposed within the shaft being fluidly connectable to an outside surface of each mounting pin to provide oil between each mounting pin and drive roller.    
   
   
       2 . The toroidal transmission of  claim 1 , wherein oil provided between each mounting pin and drive roller exits the rotor units and travels down the stator races and returns to the oil reservoir via a return path driven by differential oil pressure.  
   
   
       3 . An apparatus for transmitting power and/or motion while changing one rotary input speed to a different output speed at a chosen fixed ratio, the apparatus including a plurality of internal, motion and force conveying rotor units that are simultaneously engaged in a geometric construct of intersecting grooves, all of which include varied lead angles throughout an XYZ space in which the rotor units are continuously movably engaged, the apparatus including an optimum number of grooves to achieve the chosen fixed ratio, with the intersection of the grooves dictating an optimum number of load-sharing rotor arms which can simultaneously engage in the grooves so as to maintain sufficient wall thickness and bending strength for the walls between the grooves at all points, wherein the rotor units are positioned at mathematically precise mounting positions on a yoke which is attachable to a high torque shaft so as to meet the precise engagement requirements of the arms of the rotor units in the grooves, with the lead angles chosen to provide maximum bi-directional running efficiency.  
   
   
       4 . The apparatus according to  claim 3 , in which the geometric construct of the intersecting grooves and the required mounting positions of the rotor units on the yoke is translated into an XYZ space related machining program for a variety of transmission ratios so as to enable digitally controlled precision machining of the grooves and mounting positions of the rotor units on the yoke.  
   
   
       5 . The apparatus according to  claim 4 , in which force conveying capability of the engaged rotors includes a first super-hard and durable surface upon which a rolling barrel-shaped contact sleeve exerts a strong, small area contact force, with the contact force being transmitted via the sleeve wall from a large area hydrodynamic oil wedge created at the inside of the sleeve with the aid of a stationary, strong-force conveying pin through which the oil is supplied via feed grooves (the M-sleeve).  
   
   
       6 . The apparatus according to  claim 5 , wherein the first surface includes nanopowder including nanoparticles in Hot Isostatically Pressed condition whose hardness relates quadratically inversely to the smallness of the nanoparticles, with the second surface including high temperature melting material so as to be unaffected by the heat generated at the small area point of contact, and a back surface on the inside of the sleeve which features high surface energy to aid in the formation of an oil wedge between a sleeve inner surface and the stationary pin surface on which the sleeve rotates.  
   
   
       7 . The apparatus according to  claim 6 , wherein the first surface includes an anodized aluminum surface in which nanosize crystallites of Si 3 N 4  are embedded thus combining hardness, durability, and superior thermal conductivity.  
   
   
       8 . The apparatus according to  claim 5 , further comprising a self-feeding lubrication system in which the low-speed, high-torque shaft contains an oil reservoir which connects via feed channels to the yoke to feed oil to the rotor arms and the sleeves mounted thereon to create the oil wedges.  
   
   
       9 . The apparatus according to  claim 8 , wherein centrifugally spread oil returns to the reservoir via the stator grooves and a connecting ring channel.