Abstract:
A variable speed transmission includes an actuator mechanism that can be remotely activated to cause engagement of a drive unit and to subsequently vary the speed of the drive unit using the same activation mechanism. The variable speed transmission can include a first pulley that has a first and second face that are movable relative to each other by activation of the actuator mechanism. When the first and second faces of the first pulley are located in a first position, a belt located on the first pulley remains motionless. The first and second faces can be moved by the actuator mechanism into a second position where the first and second plates engage the belt with enough frictional force to cause the belt to start moving about the first pulley. The first and second faces of the first pulley can also be moved between the second position and a third position such that the space between the faces becomes smaller. As the space between the faces becomes smaller, the belt moves outward and away from the rotational axis of the pulley, thus moving about the axis faster as the space between the faces gets smaller.

Description:
This is a divisional of application application Ser. No. 09/739,795 filed on Dec. 20, 2000, now U.S. Pat. No. 6,592,478. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to power equipment, including but not limited to mowers, tillers, snow blowers, and tractors, and more particularly, to a variable speed transmission and method for using the variable speed transmission. 
   2. Discussion of Related Art 
   Conventional power equipment such as lawn mowers, snow blowers, mulchers, etc. often include “self-propulsion” mechanisms for automatically driving the wheel, track or other drive mechanism used to propel the power equipment. Typically, the self-propulsion drive mechanism is activated by engaging a transmission that connects/disconnects the transmission shaft to the drive wheel. The speed of the drive wheel varies proportionally with the speed of the engine. Accordingly, the speed of the drive wheel can only be varied by changing the throttle position or by changing the gear ratios inside the transmission to increase/decrease the speed of the engine. 
   Recently it has become desirable to provide all types of power equipment with variable speed transmissions in order to smoothly vary the drive speed of the power equipment without increasing/decreasing engine speed to vary the drive speed. One attempt at providing such a device is currently incorporated in power equipment produced and sold in Europe by France Reductor, Inc. Idler pulley systems have also been used in an attempt to provide variable speed power equipment. 
   The France Reductor VST includes a first belt that is attached between a drive pulley on the engine output shaft and a driven pulley on a rotational shaft. A second pulley is attached to the same rotational shaft as the driven pulley and is locked and rotates synchronously with the driven pulley. A second belt is attached between the second pulley and a second driven pulley connected to a transmission shaft. The transmission shaft is connected to a transmission that transmits rotational power to a drive wheel or other drive mechanism. A clutch located in this transmission can be actuated to engage/disengage the transmission and transmit/disengage rotational power to the drive mechanism. 
   In order to vary the speed of the drive mechanism, a plate supporting the rotational shaft can be moved against the bias of a spring to tension and loosen the first belt and second belt, respectively. The first driven pulley and the second drive pulley (both of which are located on the same rotational shaft) have variable width grooves that are caused to vary when their respective belts are tensioned and loosened. Accordingly, when the first belt is tensioned, the first belt moves deeper into the groove of the first pulley towards the rotational axis of the rotational shaft, thus rotating the rotational shaft at ever increasing speeds as tension in the belt increases. Likewise, when the second belt is simultaneously loosened, the groove in the second drive pulley becomes narrower and the second belt moves out of the groove and away from the rotational axis of the rotational shaft, thus increasing the speed of the second belt and ultimately increasing the speed of the drive mechanism. Two belts are required in such a system to provide the necessary increase in variable speed output for the power equipment drive mechanism. In addition, two control mechanisms are necessary such that one control mechanism can actuate the transmission and one control mechanism can vary the speed of the transmission. 
   Because the France Reductor VST system requires two belts, four pulleys, two control mechanisms and a separate clutched transmission, the cost of the system and the space requirements are both relatively high. It is usually necessary to mount this VST system on top of a housing structure in order to fit such a large system on power equipment. In addition, the many different parts make the system susceptible to mechanical failures and creates problems with the range of aesthetic design available to power equipment that incorporates such a system. Furthermore, the actuation of the system is a two step process, and speed variation can be sudden at times if the transmission and the variable speed actuation mechanisms are not actuated in the correct order. The belts are also constantly moving in this related art VST system. 
   Another type of VST system that is commonly used in power equipment includes a hydrostatic transmission for varying the speed output to a drive unit. In such a system, a single control mechanism can be used to vary the speed of a drive unit from a neutral position to maximum speed. However, such transmissions are relatively expensive to manufacture. In addition, maintenance and repair of such a system are significantly more difficult and expensive than maintenance and repair of belt drive and/or geared transmission systems. 
   SUMMARY OF THE INVENTION 
   Accordingly, the present invention is directed to a variable speed transmission that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. 
   An object of the present invention is to provide an efficient, inexpensive and compact variable speed transmission that can be actuated from a neutral position through a full speed position by a single actuator mechanism. 
   Another object of the invention is to incorporate the belt into the clutch mechanism of the variable speed transmission. 
   A further object of the invention is to provide a compact single actuation variable speed transmission that is capable of producing a relatively high level of output speed; 
   Another object of the present invention is to provide a compact assembly that can be easily and adequately shielded and requires as few parts as possible. 
   A still further object of the present invention is to minimize the number of pulleys and belts necessary, and to provide a variable speed transmission that uses a single belt connected between two pulleys such that the amount of moving parts is reduced and the possibility of malfunctions are reduced. 
   An additional object of the invention is to provide a control mechanism that varies drive speed between a neutral, intermediate and full speed position while also being variably operable between these three separate positions. 
   Another object of the invention is to vary the speed of a drive mechanism for power equipment in a smooth and reliable manner. 
   A still further object of the invention is to provide a compact single actuator mechanism that controls the output speed to a drive mechanism from zero to a maximum speed by moving the actuator mechanism in a single uniform motion. 
   Another object of the invention is to incorporate the variable speed transmission into the drive shaft of a motor such that a compact arrangement of the transmission can be achieved. 
   Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description and claims hereof as well as the appended drawings. 
   To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a variable speed transmission includes: a first pulley having a rotational axis and including a first face and a second face, the first face being movable with respect to the second face; a belt located adjacent the first face and the second face of the first pulley; and an actuator located adjacent the first pulley and adapted to move the first face to move with respect to the second face between a neutral position, an intermediate position and a full speed position, the neutral position defined by the first face being located at a first position with respect to the second face, and the first face being rotatable relative to the second face, the intermediate position defined by the first face being located at a second position that is closer to the second face than when the first face is located at the first position, the belt being in frictional engagement with the first face and second face such that motion of one of the first face, second face and belt causes another one of the first face, second face and belt to move, and the full speed position defined by the first face being located at a third position that is closer to the second face than when the first face is located at the second position, the belt being located in a position further from the rotational axis of the first pulley than when the first face is located at the second position. 
   The invention also includes a variable speed transmission for continuously varying the output speed of a drive wheel from zero to an upper speed limit, which includes: a single control mechanism capable of controlling the speed of the drive wheel from zero to the upper speed limit; an actuator connected to the control mechanism; and a drive train operationally connected between the control mechanism and the drive wheel, wherein the drive train includes a first and second pulley and no more than one belt. 
   In addition, the invention includes a variable speed transmission for continuously varying the output speed of a drive wheel from zero to an upper speed limit, which includes: a single control mechanism capable of controlling the speed of the drive wheel from the upper speed limit to zero; an actuator connected to the control mechanism; and a drive train operationally connected between the control mechanism and the drive wheel, wherein the drive train includes a first and second pulley connected by a belt, the first pulley having a rotational axis, a first face and a second face, the first face being movable with respect to the second face; wherein the actuator is located adjacent the first pulley and capable of causing the first face to move with respect to the second face between a neutral position, an intermediate position and a full speed position, the neutral position defined by the first face being located at a first position with respect to the second face, and rotatable with respect to the first face, the intermediate position defined by the first face being located at a second position that is closer to the second face than when the first face is located at the first position, the belt being in frictional engagement with the first face and second face such that motion of one of the first face, second face and belt causes another one of the first face, second face and belt to move, and the full speed position defined by the first face being located at a third position that is closer to the second face than when the first face is located at the second position, the belt being located in a position further from the rotational axis of the first pulley than when the first face and second face are in the intermediate position. 
   Furthermore, the invention can include a variable speed transmission, that includes: a first pulley having a rotational axis and including a first face and a second face, the first face being movable with respect to the second face; a second pulley having a second pulley rotational axis and including a primary face and a secondary face; a belt located on the first pulley and second pulley; and an actuator located adjacent the first pulley and adapted to move the first face with respect to the second face between a neutral position and a drive position, the neutral position is defined by the first face being located at a first position with respect to the second face, and the first face being rotatable with respect to the second face, the drive position is defined by the first face and second face being frictionally engaged with the belt such that the first face, second face and belt rotate together. 
   The invention can also include a variable speed transmission, including: a first pulley having a rotational axis and including a first face and a second face, the first face being movable with respect to the second face; a second pulley having a second pulley rotational axis and including a primary face and a secondary face, the primary face being movable with respect to the secondary face along the second pulley rotational axis; a biasing mechanism located adjacent one of the primary face and secondary face of the second pulley and adapted to bias the primary face towards the secondary face; a belt located on the first pulley and second pulley; and an actuator located adjacent the first pulley and adapted to move the first face with respect to the second face between a neutral position and a drive position, the neutral position is defined by the first face being located at a first position with respect to the second face, and the first face being rotatable with respect to the second face, the drive position is defined by the first face and second face being frictionally engaged with the belt such that the first face, second face and belt rotate together. 
   Additionally, the invention can include a method for using a variable speed transmission that includes a first pulley having a rotational axis, a first face and a second face, the first face being movable along the rotational axis with respect to the second face, a belt located adjacent the first face and the second face of the first pulley, the method including driving one of the first face, the second face and the belt about the rotational axis of the first pulley; moving the first face along the rotational axis and relative to the second face such that a portion of each of the first face and the second face frictionally engages the belt to cause one of the first face, the second face and the belt to begin movement about the rotational axis of the first pulley; and moving the belt away from the rotational axis of the first pulley to cause the belt to move faster about the rotational axis of the first pulley. 
   The invention can also include a method for using a variable speed transmission that includes a first pulley having a rotational axis, a first face and a second face, the first face being movable along the rotational axis with respect to the second face, a second pulley having a second pulley rotational axis, a primary face and a secondary face, the primary face being movable with respect to the secondary face along the second pulley rotational axis, a belt connected between the first pulley and the second pulley, including: driving one of the first face, the second face and the belt about the rotational axis of the first pulley; moving the first face along the rotational axis and relative to the second face such that a portion of each of the first face and the second face frictionally releases from the belt to cause one of the first face, the second face and the belt to begin movement relative to another one of the first face, the second face and the belt. 
   The invention can also include a method for using a variable speed transmission to drive a propulsion mechanism on a piece of power equipment, including: providing a control mechanism that is connected to a drive train which drives the propulsion mechanism, the drive train including a first pulley having a rotational axis, a first sheave and a second sheave, and a belt having an inner surface located around the first pulley; permitting the first sheave to remain substantially stationary relative to the second sheave; rotating the first sheave of the first pulley with respect to the belt; and engaging the belt with the first sheave of the first pulley with enough force to begin movement of the belt about the first pulley. 
   It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings: 
       FIG. 1  is an isometric view of a variable speed transmission made in accordance with the principles of the invention; 
       FIG. 2  is an isometric view of the actuator and first pulley arrangement of  FIG. 1 ; 
       FIG. 3  is a top view of the actuator and first pulley arrangement of  FIG. 1 ; 
       FIG. 4  is a side view of the actuator and first pulley arrangement of  FIG. 1 ; 
       FIG. 5  is an operational side view of the actuator and first pulley arrangement of  FIG. 1  in a neutral position; 
       FIG. 6  is an operational side view of the actuator and first pulley arrangement of  FIG. 1  in a full speed position; 
       FIG. 7  is an operational second side view of the actuator and first pulley arrangement of  FIG. 1  in an intermediate position; 
       FIG. 8  is an isometric view of the second pulley of  FIG. 1 ; 
       FIG. 9  is a side view of the second pulley of  FIG. 1 ; 
       FIG. 10  is a disassembled view of the second pulley of  FIG. 1 ; 
       FIG. 11  is a cross-sectional split view of another embodiment of the actuator and first pulley assembly; 
       FIG. 12  is a cross-sectional split view of another embodiment of the actuator and first pulley assembly; 
       FIG. 13  is a cross-sectional split view of another embodiment of the actuator and first pulley assembly; and 
       FIG. 14  is a cross-sectional split view of another embodiment of the actuator and first pulley assembly. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference will now be made in detail to the preferred embodiments of the present invention, an example of which is illustrated in the accompanying drawings. 
     FIG. 1  illustrates an isometric top view of a preferred embodiment of the variable speed transmission (VST). The VST includes a first pulley  100  and actuator  400  connected to an engine output drive shaft  600 . A belt  300  connects the first pulley  100  to a second pulley  200 , which in turn is connected to a drive mechanism for the associated piece of power equipment. Thus, the rotational energy from the engine output drive shaft  600  can be transmitted to the drive mechanism via a first pulley  100 , actuator  400 , belt  300  and a second pulley  200 . A control mechanism  500  can be attached to the actuator  400  to vary the output speed of the drive mechanism from about zero to an engagement/intermediate position speed and then proceed to a maximum or full speed. The control mechanism  500  varies the range of output speed of the drive mechanism by causing the actuator  400  to change the respective groove width of the first and second pulleys  100 ,  200 , thus changing the radius of rotation of the belt  300  about the first and second pulleys  100  and  200 , as explained in greater detail below. In addition, the present invention provides a neutral position in which the rotational energy of the drive shaft  600  is disengaged from the drive mechanism of the power equipment. This neutral position is realized by using the belt  300  as a “clutch,” which will also be explained in greater detail below. 
   An actuator (not shown) connected to the control mechanism  500  permits an operator of the power equipment to control actuation of the actuator  400 , and to ultimately control the actuation and variance of the speed output by the drive mechanism of the power equipment. The actuator is preferably controlled using a single motion to move the actuator between a neutral position and a full speed position. One type of actuator that can be used is a U-shaped bar type actuator pivoted to a U-shaped handle of the power equipment. This type of actuator is controlled by squeezing the U-shaped bar and pivoting it with respect to the U-shaped handle to cause a control line  515  to move relative to the handle. When the U-shaped actuator bar becomes flush with and/or coplanar with the U-shaped handle, the control mechanism  500  causes the actuator  400  to be at its maximum speed position. When the U-shaped actuator bar is pivoted to its furthest angled position with respect to the U-shaped handle, the actuator is in its neutral position. Thus, the operator can propel the power equipment from zero to maximum speed by squeezing and/or otherwise moving the U-shaped actuator bar to pivot it with respect to the U-shaped handle. Of course, other actuators such as a rotary knob or pivoting lever could be used in place of the U-shaped bar actuator to control the speed of the power equipment between zero and maximum speed. 
   As shown in  FIGS. 2–7 , the actuator  400  can include a first actuator plate  410  and a second actuator plate  420 , each of which can rotate with respect to the other upon activation of the control mechanism  500 . The first actuator plate  410  can include an extension lock member  417  on its top surface  413  for locking the first actuator plate to the housing or other element of the power equipment. Thus, the second actuator plate  420  will be able to rotate with respect to both the first actuator plate  410  and the power equipment device in general. Alternatively, the first actuator plate  410  could be rotatable with respect to both the second actuator plate  420  and the power equipment device in general. Bearings  404  permit both the first and second actuator plate to rotate relative to the drive shaft  600  located in shaftway  403  of the actuator plates  410  and  420 . The bearings  404  can be the same or different style bearings and can be selected to conform to the necessary performance characteristics desired for a particular application of the invention. In addition, when economical considerations mandate, it is possible in some circumstances to not use bearings or consolidate various bearings. A retaining clip  601  can be provided to keep the actuator  400  in position on the drive shaft  600 . 
   The control mechanism  500  is preferably connected to the actuator  400  by an attachment ball  517  that is locked into a mating actuator cutout  426  in the second actuator plate  420 . A cable retainer  510  can be fixed to an actuator extension  418  on the first actuator plate  410  by inserting a lock nub  512  that extends from the cable retainer  510  into an aperture in the extension  418  of the first actuator plate  410 . A control cable (or control line)  515  located within the cable retainer  510  can move relative to the cable retainer  510  and the first actuator plate  410 . Accordingly, movement of the control line  515  causes the second actuator plate  420  to move/rotate with respect to the first actuator plate  410 . A ball/ramp mechanism  443  (see  FIG. 3 ) can be used in combination with an actuator spring  430  to bias the second actuator plate  420  to its initial position with respect to the first actuator plate  410  when tension in the control line  515  is released. 
   The ball/ramp mechanism  443  includes balls  440  located between the actuator plates  410  and  420  which ride up respective ramps  441  located in one of the first and second actuator plates  410  and  420 . As the second plate  420  rotates with respect to the first actuator plate  410 , the balls  403  ride up the ramps  441  and cause the second actuator plate  420  to separate and move away from the first actuator plate  410  against the bias of springs  430 . Springs  430  are attached to the first actuator plate  410  and extend through slots  427  located in a springway portion  423  of the second actuator plate  420 . The slots  427  are shaped to allow the springs  430  to ride along the lower surface  424  of the second actuator plate  420  as the second actuator plate  420  rotates relative to the first actuator plate  410 . The springs  430  bias the second actuator plate  420  towards the first actuator plate  410  throughout rotation of the plates. The springs  430  are connected to the first actuator plate  410  by inserting a portion of each spring  430  into a spring lockhole  416  in the top surface of the first actuator plate  410 . The spring  430  extends downward through a spring slot  415  in the first actuator plate  410 . 
   The rotation of the first actuator plate  410  with respect to the second actuator plate  420  can be limited by providing abutments  412  and  422  in the respective first and second actuator plates  410  and  420 , respectively. The abutments  412  and  422  ride in slideways  421  and  411 , respectively, of the opposing first and second actuator plates  420  and  410 . Thus, the rotation of the first and second actuator plates  420  and  410  is limited by the length of the slideways  411  and  421  and the length of their corresponding abutments  422  and  412 . 
   The first pulley  100  includes a first sheave  110  and a second sheave  120  which form a groove  130  therebetween. The second sheave  120  can be connected to rotate with the drive shaft  600  such that both the second sheave  120  and drive shaft  600  rotate with respect to the first sheave  110  of the first pulley  100 . The first sheave  110  can also rotate with respect to the drive shaft  600  and with respect to the second actuator plate  420 . Bearings  404  can be provided between both the first sheave  110  and drive shaft  600  and between the first sheave  110  and second actuator plate  420  to facilitate their relative rotation. As the second actuator plate  420  moves downward by action of the control mechanism  500 , it forces the first sheave  110  of the first pulley towards the second sheave  120  of the first pulley, which decreases the width of the groove  130  of the first pulley  100 . As the groove width narrows, the belt  300  is engaged with a face  121  of the second sheave  120  of the first pulley  100 . The belt  300  becomes tensioned as it engages the face  121  and begins to rotate about the rotational axis of the first pulley  100  due to frictional force between the rotating face  121  and belt surface. This action is what is referred to above as using the belt  300  as a clutch mechanism. 
   The groove  130  can be further narrowed by moving the control mechanism  500  to force further separation of the actuator plates  410  and  420 , which forces the first sheave  110  closer to the second sheave  120  of the first pulley. The faces  111  and  121  of the first and second sheave  110  and  120  include angled surfaces  114  and  214 . As the first and second sheave  110  and  120  move towards each other, the belt is forced to rise radially along these angled surfaces  114  and  124  out of the groove  130 . Thus, as the pulley first sheave  110  and pulley second sheave  120  move towards each other, the belt  300  moves away from the rotational axis of the drive shaft  600  and the rotational speed of the belt increases. The drive mechanism is at maximum speed when the belt  300  is at a furthest position from the rotation axis and the first sheave  110  is closest to the second sheave  120  of the first pulley. 
   The first pulley sheave  110  can also include an extension surface  112  that extends along the rotational axis of the drive shaft  600  and between the first angled surface  114  and second angled surface  124  of the first and second sheaves  110 ,  120 . When the invention is in its neutral position (e.g., when no actuation force is applied to the control mechanism  500 , the first and second actuator plates  410  and  420  are together, and the first and second sheave of the first pulley  110  and  120  are at their widest position), the belt  300  tension causes the groove in the first pulley to return to its widest position, and the belt  300  rests on the extension surface  112 . The drive mechanism remains effectively at a geared idle or geared neutral state. 
   The belt  300  is preferably connected between and supplies power from the drive shaft  600  to the second pulley  200 . The second pulley  200  can be connected to a drive mechanism of the power equipment for propelling the equipment. 
   As shown in  FIGS. 8–10 , the second pulley  200  can include a second pulley first sheave  210  that can be connected to and rotate with a second pulley second sheave  220 . A hub  227  can be formed in the second pulley second sheave  220  and shaped to extend through a keyway  218  in a collar  217  of the second pulley first sheave  210 . The relative shape of the hub  227  and keyway  218  rotationally lock the sheaves  210  and  220  together. The hub  227  includes a shaftway  225  for connection to a driven shaft of the drive mechanism. When the second pulley first sheave  210  is connected to the second pulley second sheave  220 , an attachment disk  250  can be attached to the hub  227  of the second pulley second sheave  220  to keep the first and second sheaves  210  and  220  together. The attachment disk  250  can be attached to the hub  227  by a number of screws  253  that extend though holes  251  in the disk  250  and attach to screw holes  223  in the hub  227  of the second sheave  220 . Various shaped hubs can be used in the invention, including a single key  20  hub. 
   A spring  240 , which can be a diaphragm type or belleville spring, can be located between the attachment disk  250  and a top surface  216  of the first sheave  210  to bias the first sheave  210  towards the second sheave  220  of the second pulley. The spring  240  rides along the outside of collar  217  in the second pulley first sheave  210  and can include an upper ring  241  and lower ring  242  separated from each other by an intermediate leaflet  243 . The upper and lower rings  241  and  242  lie flat on the lower surface of the attachment disk  250  and the top surface  216  of the first sheave  210 , respectively. The spring  240  permits the groove  230  formed between the first sheave  210  and second sheave  220  of the second pulley  200  to vary in width in accordance with the tension in the belt  300 . 
   The belt  300  can ride between a first face  211  of the first sheave  210  and a second face  221  of the second sheave  220  of the second pulley  200 . Angled surfaces  214  and  224  located on the first and second face  211  and  221 , respectively, tend to move the belt away from the rotational axis of the second pulley as the first sheave  210  and second sheave  220  of the second pulley  200  move towards each other under the bias of spring  240 . Thus, when tension decreases in the belt  300 , the bias of the spring  240  moves the first and second sheaves  210  and  220  together to decrease the width of groove  230 . The belt  300  is then caused to move further from the rotational axis of the second pulley, thus slowing the rotational speed of both the second pulley  200  and the drive mechanism to which the second pulley  200  is connected. By contrast, when the belt  300  is tensioned (e.g., when the control mechanism  500  is activated to cause the actuator  400  to move the first pulley sheaves  110  and  120  towards each other to “clutch” the belt  300  into motion/tension), the tension in the belt  300  overcomes the bias in the spring  240  to separate the first and second sheaves  210  and  220  of the second pulley, thus widening the groove  230 . As the groove  230  widens, the belt  300  rides inward along the first and second face  211  and  221  of the second pulley  200  towards the rotational axis of the second pulley. As the belt  300  approaches the rotational axis of the second pulley  200 , the radius of rotation about the pulley decreases and the speed of rotation is therefore increased accordingly. Thus, the drive mechanism is driven at increasing speeds as the belt  300  is tensioned by the control mechanism  500 . Because the groove width of both the first and second pulleys  100  and  200  changes in opposite directions during tensioning (or loosening), a two-fold increase (or decrease) in speed can be achieved at the output shaft of the second pulley  200 . 
   As shown in  FIGS. 11 and 12 , the first pulley  100  actuator  400  can be configured to attach between a mower blade  700  and the lower housing  800  of a mower. The right half of the split view of  FIGS. 11 and 12  depicts an embodiment in which many of the pulley  100  and actuator  400  components are molded components and the first pulley is in the maximum speed position (e.g., the actuator  400  is actuated and the first sheave  110  and second sheave  120  of the first pulley  100  are at their minimum separation distance and the belt  300  is furthest from the rotational axis of the drive shaft  600 ). The left half of the split view of  FIG. 11  depicts an embodiment in which many components of the pulley  100  and actuator  400  are plate components and the first pulley  100  and actuator  400  are in a neutral position. However, belt  300  is shown at both a neutral and high speed position in this portion of the split figure. 
     FIGS. 13 and 14  show other embodiments of the present invention in which a “blade brake clutch”  900  is incorporated onto the same drive shaft  600  as are the first pulley  100  and actuator  400 . In this embodiment, many of the components are shown as being made from metal plate material. However, each of these parts could also be manufactured as molded components. The right half of the split view of  FIGS. 13 and 14  depict the blade brake clutch mechanism in its actuated position in which a separate blade clutch disengages the drive shaft from an output member and a blade brake is applied to the disengaged output member to stop rotation of the output member and any equipment, such as mower blades, attached to the output member. The left half of the split views in  FIGS. 13 and 14  depict the blade brake clutch in a non-actuated position in which the drive shaft  600  is connected and rotates an output member. 
   When the belt  300  rides in the first pulley  100 , a preferable range for the outer diameter of the first pulley  100  as measured from the outside of the belt varies from 48.2 mm at low speed/neutral, to 68.2 at mid speed, to 88.2 mm at maximum speed. Similarly, when the belt  300  rides in the second pulley  200 , a preferable range for the outer diameter of the second pulley  200  as measured from the outside of the belt varies from 103 mm at low speed/neutral, to 83.5 mm at mid-speed, to 64 mm at maximum speed. Of course, the specific value for the diameter of the first and second pulley can change depending on the particular application or desired speed ratio. The horsepower required for driving a mower engine at 3100 rpm which includes a first and second pulley with the above noted diameter variances between neutral and maximum speed is approximately 0.16 hp when cruising, and 0.47 hp at maximum load. In addition, the ground speed can vary from 1.22 mph to 3.61 mph in the preferred embodiment of the invention. 
   In the above embodiments of the invention, the force required to actuate the actuator  400  can be relatively low such that a low tension force is required in the cable  515 . This low tension force provides good operating stability and durability for the variable speed transmission and also permits easy operation by users of the device. 
   Although the invention has been described with respect to preferred embodiments of the invention, it should be understood that many variations of these embodiments fall within the scope and spirit of the claimed invention. For example, the specific speed, horsepower and diameter values described above could be changed to meet a particular application or to fulfill different objectives. In addition, the invention could include an embodiment in which the actuator and first pulley are attached to a driven shaft, and the second pulley as described above could be attached to the drive shaft or engine output shaft. The invention could also be mounted in many different ways to the power equipment, including under the housing, above the housing and even on the side of a piece of power equipment. 
   The actuator is disclosed as including a ball/ramp device  243  for causing separation of the actuator plates. However, other known actuator devices could be incorporated in the present invention without departing from the spirit and scope of the invention. For example, a Blade Brake Clutch mechanism, as disclosed in applicant&#39;s co-pending U.S. patent application Ser. No. 09/628,447, which is hereby incorporated by reference, could be used in place of the actuator mechanism disclosed above. The actuator could also be attached to the power equipment in different manners. For example, the second (or lower) actuator plate could be fixed to the power equipment, and the first (or top) actuator plate could be connected to a control device and rotate with respect to the power equipment and second actuator plate. 
   Although the second pulley is disclosed as having a first sheave and second sheave that are rotationally locked with respect to each other, it is within the scope of the present invention to include first and second sheaves that can rotate with respect to each other in the second pulley. Such a configuration could provide a smoother transition when engaging the drive mechanism and/or actuator mechanism during speed change. The first sheave and second sheave of the first pulley are disclosed as being separate from each other. However, it is contemplated that these structures could contact each other or be separated by a bearing or the like. In addition, the extension portion (or hub portion) of the first sheave of the first pulley could conceivably be disconnected from the first sheave and ride freely on the drive shaft. Furthermore, the extension portion of the first sheave could possibly be eliminated from the configuration depending on the type of belt used and the friction parameters of all moving parts. 
   Additionally, it is contemplated that the first pulley could be located at different positions relative to the actuator, including above or below the actuator on the drive shaft, without departing from the scope of the invention. The first sheave could also be driven with the drive shaft (instead of the second sheave being driven as disclosed above) and the second sheave could be actuated to move towards the first sheave to narrow the groove of the first pulley and move the belt into contact with the rotating first sheave. In addition, the actuator and first pulley as described above could be located on the driven shaft of the transmission drive train, and the belt could be driven by a drive pulley that is configured similar to the second pulley described in the embodiment above. The actuator could be activated to cause a first or second sheave of the driven pulley to engage with the moving belt at the driven pulley side of the transmission. In this arrangement, the belt would be moving and the driven pulley would “clutch” the moving belt to effect the variable speed transmission. 
   The relative sizes of the first and second pulley and belt can be varied in accordance with the desired speed ratios and in accordance with the design parameters of specific power equipment. In this same regard, the actuator size can be varied as well. The materials out of which the system is manufactured also varies widely, and includes cast metals, metal plating, plastics, rubbers, ceramic, etc. The selection of materials will effect the amount of friction necessary to engage or clutch the belt, and therefore could be a significant consideration in designing the invention for a particular application. 
   The control device could also be configured differently and remain within the scope of the present invention. For example, the control mechanism could be a magnetic, hydraulic, pneumatic, bellcrank or other type actuation device, and possibly could be a solenoid or other electronic actuator device. 
   It will be apparent to those skilled in the art that various modifications and variations can be made in the transmission of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.