Abstract:
A continuously variable transmission includes at least one transmitter having two graduated surfaces mounted to provide frictional engagement with a driving cylinder and a driven cylinder. A shifter having two graduated surfaces is axially mounted within the housing. The transmitter is not mounted on a shaft, but is urged into engagement with the driving cylinder and the driven cylinder by two elongated followers. Each follower includes a first end and an opposing second end. Axial movement of the shifter provides simultaneous and opposing movement of the first and second followers to impart pivotal movement of the axis of rotation of the transmitter.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not Applicable 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not Applicable 
   BACKGROUND OF THE INVENTION 
   1. Field of Invention 
   This invention pertains to continuously variable transmissions. 
   More particularly, this invention pertains to a continuously variable transmission including at least one double-coned transmitter in frictional engagement with a driving cylinder and a driven cylinder. 
   2. Description of the Related Art 
   Many efforts have been made to develop continuously variable transmissions. Conical and spherical surfaces have been used to transmit energy from a drive cylinder to a driven cylinder at different rates of rotation based upon the varying diameter of the cone or sphere. Generally, the cone or sphere is rotatably mounted upon a shaft which is movable either axially or pivotally to adjust the specific area of frictional engagement of the cone or sphere with another rotating surface mechanically connected to a drive shaft or a driven shaft. 
   BRIEF SUMMARY OF THE INVENTION 
   According to one embodiment of the present invention, at least one transmitter including two graduated surfaces is mounted to provide frictional engagement with a driving cylinder and a driven cylinder. The transmitter is not mounted on a shaft, but is urged into engagement with the driving cylinder and the driven cylinder by two elongated followers. Each follower includes a first end and an opposing second end. Upon the first end of each follower a wheel is rotatably mounted for rotational engagement with one of the two graduated surfaces of the transmitter. The second end of each follower engages with a graduated surface of a shifter. The shifter includes two coaxial opposing graduated surfaces. The shifter is axially movable to provide simultaneous and opposing movement of the two followers for each transmitter. Accordingly, as the shifter is moved axially, the wheels of the followers cause the axis of rotation of the transmitter to pivot and change the location of engagement of the two wheels with the two graduated surfaces. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     The above-mentioned features of the invention will become more clearly understood from the following detailed description of the invention read together with the drawings in which: 
       FIG. 1  is a schematic cross-sectional view of one embodiment of the present invention; 
       FIG. 2  is schematic elevation view of one embodiment of the present invention; 
       FIG. 3  is a schematic plan view of one embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to the drawings, in which like reference numbers refer to like parts, an apparatus for continuously variable transmission of energy from a drive cylinder to a driven cylinder is disclosed. 
   In the depicted embodiment, twelve transmitters and related followers are disclosed. The number of transmitters employed in a particular application will vary. Moreover, in the depicted embodiment the twelve transmitters are substantially identical. Accordingly, only one of the transmitters, along with the mechanism associated therewith will be described in detail. It will be understood that the remaining transmitters are constructed in substantially the same manner and operate in substantially the same manner. 
   Referring to  FIG. 1 , an elongated shifter  10  is coaxially mounted in a housing  11  on a rod  12 . The shifter  10  comprises a first end portion  14 , an opposed end portion  16  and a central portion  18  located between the first end portion  14  and the second end portion  16 . The first end portion  14  is shaped as a frustum, having a narrow end connected to the central portion  18 . Similarly, the second end portion  16  is shaped as a frustum, having a narrow end connected to the central portion  18 . The central portion  18  is generally cylindrical in shape. It will be recognized that the central portion  18  may be a single piece or may be separated into two or more sections. 
   The shifter  10  is movable longitudinally along its axis, either along the rod  12  or with the rod  12 . 
   A first elongated follower  20 , including an inboard end  22  and an outboard end  24 , extends radially from the first end portion  14  of the shifter  10  through the housing  11 . The inboard end  22  of the follower  20  terminates in a contact surface  26  that engages the conical outer surface  28  of the first end portion  14 . The outboard end  24  terminates in a rotatable wheel  30 . The axis of rotation of the wheel  30  is parallel to the axis of the shifter  10 . 
   Similarly, a second elongated follower  20   a  including an inboard end  22   a  and an outboard end  24   a , extends radially from the second end portion  16  of the shifter  10  through the housing  11 . The inboard end  22   a  of the follower  20   a  terminates in a contact surface  26   a  that engages the conical outer surface  29  of the second end portion  16 . The outboard end  24   a  terminates in a rotatable wheel  30   a . The axis of rotation of the wheel  30   a  is parallel to the axis of the shifter  10 . 
   An elongated transmitter  34  is mounted adjacent to the wheels  30  and  30   a . The transmitter  34  comprises a first end portion  36  and a second end portion  38 . In the depicted embodiment, the first end portion  36  and the second end portion  38  both comprise cones having a common base. It will be recognized that the first end portion  36  and/or the second end portion  38  may be shaped as a frustum. The outer surface  40  of the first end portion  36  is rotatably engaged by the wheel  24 . Similarly, the outer surface  42  of the second portion  38  is rotatably engaged by the wheel  24   a.    
   Each of the followers  20  and  20   a  includes a biasing mechanism, such as springs  32  and  32   a , respectively. The biasing mechanism ensures the continuous frictional engagement of the contact surfaces  26  and  26   a  with the outer surface  28  and  29 , respectively, of the shifter  10  and continuous frictional engagement the wheels  30  and  30   a  with the outer surfaces  40  and  42  of the transmitter  34 . 
   The outer surface  40  of the transmitter  34  is frictionally engaged with a driven cylinder  44 . The outer surface  42  of the transmitter  34  is frictionally engaged with a drive cylinder  48 . 
   In the depicted embodiment, fins  52  and  54  are mounted upon the cylinders  44  and  48 , respectively. Rotation of the cylinders  44  and  48  carrying fins  52  and  54 , respectively, effects a substantial air flow around the mechanism. Rotation of the drive cylinder  48  carrying fin  54  will draw air into the mechanism. Rotation of the driven cylinder  44  carrying fin  52  will exhaust air from the mechanism. 
   In operation, rotational energy is applied to the drive cylinder  48 , as by an engine or motor, for example. Frictional engagement of the drive cylinder  48  with the outer surface  42  of the transmitter  34  effects rotation of the transmitter  34  around its axis. Frictional engagement of the outer surface  40  of the transmitter  34  with the driven cylinder  44  effects rotation of the cylinder  44 . 
   The relative speeds of rotation of the driven cylinder  44  and the drive cylinder  48  are controlled by the particular engagement of the cylinder  44  and  48  with the outer surfaces  40  and  42 , respectively. That is to say, if the cylinder  44  engages the first end portion  36  of the transmitter  34  at a location having a circumference that is equal to the circumference at the point of contact between the cylinder  48  and the second end portion  38  of the transmitter  34 , then the speeds of the driven cylinder  44  and the drive cylinder  48  will be equivalent. However, if the cylinder  44  engages the first end portion  36  of the transmitter  34  at a location having a circumference that is less than the circumference at the point of contact between the cylinder  48  and the second end portion  38  of the transmitter  34  (as depicted in  FIG. 1 ), then the rotational speed of the drive cylinder  48  will be greater than the rotational speed of the driven cylinder  44 . Similarly, if the cylinder  44  engages the first end portion  36  of the transmitter  34  at a location having a circumference that is greater than the circumference at the point of contact between the cylinder  48  and the second end portion  38  of the transmitter  34  (the reverse of  FIG. 1 ), then the rotational speed of the drive cylinder  48  will be less than the rotational speed of the driven cylinder  44 . 
   Variation of the relative circumferences of the locations of engagement is accomplished by the shifter  10 . As noted hereinbefore, the shifter  10  is mounted for longitudinal movement along its axis and the followers  20  and  20   a  are frictionally engaged with the first end portion  14  and the second end portion  16 , respectively, and extend through the housing  11 . The followers  20  and  20   a  are mounted for floating longitudinally movement. 
   Axial movement of the shifter  10  which increases the circumference of the location of engagement between the first end portion  14  and the inboard end  22  of the follower  20 , urges the follower  20  radially outwardly. The outward radial movement of the follower  20  forces the transmitter to adjust the location of contact between the first end portion  36  and the wheel  30  to a location of reduced circumference. Simultaneously, the location of engagement between the end portion  16  and the inboard end  22   a  of the follower  20   a  is changed to a location of reduced circumference, thus allowing the follower  22   a  to move radially inwardly and allowing the wheel  30   a  to engage the second end portion of the transmitter  34  at a location of increased circumference. 
   The simultaneous opposing movement of the first follower  20  and the second follower  20   a  imparts a pivotal movement to the axis of rotation of the transmitter  34 . 
   Although the depicted embodiment employs cone-shaped and frustum shaped surfaces, i.e. linear graduated surfaces, for the graduated surfaces, it will be recognized that a non-linear, graduated surfaces, such as a parabola may be employed without departing from the spirit and scope of the present invention. 
   Those skilled in the art will recognize that the disclosed continuously variable transmission is surprisingly simple in construction, yet provides continuously variable transmission of rotational energy from a drive cylinder to a driven cylinder. 
   Various modifications of structures and materials and can be used without departing from the spirit and scope of the present invention. 
   While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant&#39;s general inventive concept.