Abstract:
A transmission utilizing a translating gear and links to provide a high speed ratio in a small, efficient package. A gear set has an input and an output, with a speed ratio between the input and the output. The gear set has one gear that rotates and that provides a circular path for another gear. The rotational gear is attached to the input or the output. The other gear is engaged with the rotational gear and translations on a circular path. The second gear is connected with linkages to the other of the input or the output which resembles a crankshaft FIG.  1  shows the fully assembled transmission.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to planetary gear sets of the type that are use to transfer torque from one rotating shaft to another where the two shafts are rotating at different speeds. 
       BACKGROUND OF THE INVENTION 
       [0002]    Transmissions or gear-boxes are used in a variety of applications to change the speed and torque provided by a prime mover such as an automotive engine, wind power system, or wind turbine. Two or more gears are used in transmission of rotational motion, torque and power from on rotating shaft to another. 
         [0003]    A familiar use of gears is in power transmission of an automobile. The engine, rotation at high speed, delivers power to the transmission, which gears reduce the speed at which the power is transmitted to the drive shaft. Thus the wheels rotate at a speed much lower than that at which the engine turns. 
         [0004]    One type of arrangement of gears in many types of transmissions and gearboxes are planetary gear sets. Planetary gear sets are compact and optimized combination of gears to transfer torque from one rotating shaft to another. 
         [0005]    A prior art planetary gear set has four parts which are the sun gear, the ring gear, and planet gears and the planet carrier. In one configuration, the sun gear rotates, causing the planet gears to rotate about the sun gear. The planet gears are inside of the ring gear, which rotates at a reduced speed. 
         [0006]    Conventional planetary gear sets are limited in speed ratios to no more than 9:1. Higher speed ratios require a stack of planetary gear sets, also known as multiple stage gear sets. The use of a stack reduces the compactness of the gear set and increases the complexity of the device as well as decreases efficiency. 
         [0007]    It is desirable to have planetary gear set with high speed ratios for a variety of applications. 
       SUMMARY OF PRESENT INVENTION 
       [0008]    The present invention provides a gear set that comprises an input and an output, with a speed ratio between the input and the output. A first gear rotates and provides a circular path for another gear that is engaged with the first gear. The first gear is connected to one of the input or the output. A second gear is engaged with the first gear and translates in the path relative to the first gear. The second gear is connected with linkages to the other of the input or the output which resembles a crankshaft. 
         [0009]    In accordance with one aspect of the present invention, the first gear comprises a spur gear and the second gear comprises a ring gear. 
         [0010]    In accordance with still another aspect of the present invention, plural second gears are engaged with the first gear and are interconnected with each other by linkages to the crankshaft. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of a gear set of the present invention, in accordance with a preferred embodiment. 
           [0012]      FIG. 2  is a schematic view of a vehicle drive train, incorporating the gear set of the present invention. 
           [0013]      FIG. 3  is a prior art three gear train. 
           [0014]      FIG. 4  is a prior art planetary gear train. 
           [0015]      FIG. 5  is an end view of the ring gear and translating gear of  FIG. 1 . 
           [0016]      FIG. 6  is the same as  FIG. 1   
           [0017]      FIG. 7  is an exploded view of components of  FIGS. 1 and 6 . 
           [0018]      FIG. 8  is an exploded view of components of  FIGS. 1 and 6 . 
           [0019]      FIG. 9  is an exploded view of components of  FIGS. 1 and 6 . 
           [0020]      FIG. 10  is the frame component of  FIGS. 1 and 6 . 
           [0021]      FIG. 11  is an illustration of the circular translational motion of the planetary gear, or translational gear, inside of a ring gear of the embodiment of  FIGS. 1 and 6 . 
           [0022]      FIGS. 12-20  are perspective views of the gear set of  FIGS. 1 and 6 , illustrating the movement of the translational gear inside of the ring gear.  FIGS. 12A-20A  are end views of the same. 
           [0023]      FIG. 21  a perspective view of a gear set of the present invention with multiple translational gears. 
           [0024]      FIG. 22  is an exploded view of components of  FIG. 21 . 
           [0025]      FIG. 23  is an exploded view of components of  FIG. 21 . 
           [0026]      FIG. 24  is an exploded view of components of  FIG. 21 . 
           [0027]      FIG. 25  is an exploded view of components of  FIG. 21 . 
           [0028]      FIG. 26  is an exploded view of components of  FIG. 21 . 
           [0029]      FIG. 27  is a perspective view of spur gear rollers and translational gear outer racer. 
           [0030]      FIG. 28  is a perspective view of translational gear alignment guide. 
           [0031]      FIG. 29  is a perspective view of spur gear rollers alignment guide. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0032]    The present invention provides a gear set that can be used in a number of applications.  FIG. 1  shows the gear set  1  in accordance with a preferred embodiment. The gear set has a translational or ring gear  22  and a spur gear  23 . The spur gear  23  rotates. The translational gear  22  moves outside of the spur gear  23 , but the motion is not rotational. Instead, the translational gear  22  translates in a circular path relative to the spur gear  23 . The circular translational motion enables the gear set to provides higher speed ratios than conventional gear sets. 
         [0033]    The gear set  1  has a low torque shaft  20  and a high torque shaft  21 . 
         [0034]    The gear set can be used in a number of applications. An example of one such application is shown in  FIG. 2 , which shows a vehicle drive train  13 . Still another example application is use in a wind power system or wind turbine. Referring to  FIG. 2 , the drive train  11  has a prime mover  8 , such as an internal combustion engine. The internal combustion engine can be powered by gasoline, diesel, natural gas, etc. Other types of prime movers can be used, such as electric motors. The gear set is located in a transmission  9  or gear box. The transmission  9  has an input, such as shaft  11  connected to the prime mover  8  and an output, such as a shaft  11 A, connected to the load  10 . The load  10  in the illustration is a set of vehicle wheels. In the application shown in  FIG. 2 , the input shaft  11  would correspond to the low torque shaft  20   FIG. 1  and the output shaft  11 A of  FIG. 2  would correspond to the high torque shaft  21  of  FIG. 1 . The gear set  1  serves as a speed reducer when conveying power from the prime mover  8  to the wheels  10 . 
         [0035]      FIGS. 3 and 4  show prior art gear sets or gear trans. The gear set shown in  FIG. 3  is a three-gear train, using spur gears  14 . The low torque shaft is connected to the small gear (on the right side of  FIG. 3 ), while the high torque shaft is connected to the large gear (on the left side of  FIG. 3 ). If the input is connected to the low torque shaft, then the small gear rotates the other two gears and the output shaft. For each revolution of the small gear, the large gear only rotates a part of a revolution. Thus, speed reduction is accomplished. 
         [0036]      FIG. 4  shows a prior art planetary gear train. There is a sun gear  15 , which is connected to a low torque shaft. Several planetary gears  16  are in rotating contact with the sun gear and also in rotating contact with a ring gear  17 . A high torque shaft (not shown) is connected to the ring gear. If the input is connected to the sun gear  15 , then as the sun gear rotates, the planetary gears  16  revolve around the sun gear and rotate the ring gear  17 . Speed reduction is accomplished because the ring gear rotates only a part of a revolution for each revolution of the sun gear. 
         [0037]      FIG. 5  shows the translational and spur gears  22 ,  23  of the gear set  1  of the present invention. The spur gear  23  rotates like the sun gear  15  of the planetary gear set. Unlike the planetary gear set, where the ring gear  17  and the planetary gears  16  rotate, the translational gear  22  does not rotate. Instead, the translational gear  22  translates about a circular path. This will be illustrated in further detail below. 
         [0038]    The gear set  1  will now be described, with reference to  FIGS. 1 ,  6 ,  7 ,  8 ,  9  and  10 .  FIGS. 1 and 6  show the same gear set  1 . The spur gear  23  is coupled to the high torque shaft  21 . The translational gear  22 , which is a ring gear, is located outside of the spur gear  23  so as to engage, or mesh teeth, with the spur gear. Extending from the translational gear  22  are three or more linkages which transfers the torque from the translational gear  22  to the crankshaft  24  and low torque shaft  20 . The linkages are an assembly of the short links  30 , short rocker-arms  28 , shafts  32 , long rocker-arms  29  and long links  31 . The short links  30  and long links  31  are connecting structure which pivots at both ends. The short rocker-arms  28 , shafts  32  and long rocker-arms  29  are connected together so that torque is transfer between the short rocker-arms  28  and the long rocker-arms  29 . The long links  31  are connected to the long rocker-arms  28  and the crankshaft  24 . Three or more sets of the linkages connected to the crankshaft are required to constrain the translational gear to translate about a circular path. 
         [0039]    In operation, spur ring gear  23  rotates with the shaft  21 . The spur gear can be rotated by the shaft  21 , wherein the shaft  21  is an input shaft. Conversely, the spur gear can be rotated by the translational gear  22 , wherein the translational gear  22 , linkage assembles and the crankshaft  24  rotates the output shaft  20 . Thus, the input and output are interchangeable with each other, depending upon the particular application of the gear set  1 . 
         [0040]    The spur gear  23  rotates about the longitudinal axis of the shaft  21 . The spur gear  23  defines a circular path for the translational gear  22 . The translational gear  22  is engaged with the spur gear  23  and translates about the circular path. The translational gear  22  is constrained to translational movement by the linkages and crankshaft  24 . The linkages and crankshaft  24  prevent rotational of the translational gear  22 . The linkages and crankshaft  24  are supported by the frame  26 .  FIG. 11  illustrates the circular path of the translational gear  22 . For the discussion herein, the gear  22  has a reference point A thereon. In the topmost position of the gear (referring to the orientation of  FIG. 11 ), point A is up. Point A remains up even as the gear moves about a circular path to a rightmost position, then to a lowermost position, then to a leftmost position and back to the topmost position. As can be seen, the gear  22  does not rotate. Instead, the gear  22  moves in translation about a circular path B. The circular path is defined by the spur gear  23 . (In  FIG. 11 , the diameter of the circular path B is exaggerated for illustrative purposes). 
         [0041]      FIGS. 12-20A  further illustrate the operation of the gear set. In  FIGS. 12 and 12A , the translational gear has point A in the up position. The drawings show a point of reference C located on the spur gear. In  FIGS. 12 and 12A , point C is also located in the up position. As the shaft  21  rotates (see  FIGS. 13-20A ), the spur  23  rotates, as shown by point C moving in a counter-clockwise direction. As the spur gear rotates, as shown by point C moving in a clockwise direction. As the spur gear rotates, it moves the translational gear  22  about a circular path outside of the spur gear  23 . The translational gear  22  moves to a rightmost position (see  FIG. 12A ), then to a bottommost position (see  FIG. 14A ), then to a leftmost position (see  FIG. 16A ) and back to a topmost position ( FIG. 18A ). Point A remains in the up position. Also shown in  FIGS. 12-20A , the translational gear  22  rotates the crankshaft  24  in unison. As the crankshafts rotate, shaft  20  also rotates. Thus, with each revolution of the crankshafts, the translational gear  22  competes one revolution about its circular path outside of the spur gear and the spur gear rotates part of a revolution. 
         [0042]    In the embodiments shown herein, the frames are shown somewhat schematically, for illustrative purposes. 
         [0043]      FIGS. 21 through 26  illustrate another embodiment of the gear set  1 . In this embodiment, plural translating components are used. Specifically, plural translating gears  22  are used. The translational gears are mounted on linkages, with crankshaft having multiple crank pins for receiving a respective translational gear. The translational gears are offset from each other so as to balance the centrifugal loads. For example, as shown in  FIGS. 21 through 26 , the center translational gear is offset  180  degrees apart from the two endmost translational gears. The sum of the masses of the two endmost translational gears is the same as the mass of the center translational gear. 
         [0044]    The speed ratio for the gear set  1  is provide in Table 1. Gear set  1  comprises a low torque component, a high torque component, and translating component. The speed ratio is dependent upon the number of teeth of the spur gear  23  (N S ) and the translational gear  22  (N R ). The input and output rotate in opposite directions. 
         [0000]    
       
         
               
             
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Gear Set Constraints and Speed Ratio Equations 
               
             
          
           
               
                   
                   
                 High 
                 Translating 
                   
               
               
                   
                 Low Torque 
                 Torque 
                 Component 
                 Speed Ratio Equation 
               
               
                   
                   
               
               
                   
                 Crankshaft 
                 Spur Gear 
                 Ring Gear 
                 
                   
                     
                       
                         
                           
                             - 
                             
                               N 
                               S 
                             
                           
                           
                             
                               N 
                               R 
                             
                             - 
                             
                               N 
                               S 
                             
                           
                         
                          
                         
                             
                         
                          
                         to 
                          
                         
                             
                         
                          
                         1 
                       
                     
                   
                 
               
               
                   
                   
               
             
          
         
       
     
         [0045]      FIGS. 28 and 28A  illustrate an improvement to gear set  1  which is an alignment guide between the spur gear  23  and translational gear  22 . 
         [0046]    The system has a built in self alignment capability. The centrifugal forces of the translating gear with alignment guides  42  on the spur gear and alignment guides  40  translating gear enable the gear alignment (see  FIGS. 27 ,  28  and  29 ). 
         [0047]    The foregoing disclosure and showing made in the drawings are merely illustrative of the principles of this invention and are not to be interpreted in a limiting sense.