Abstract:
A thumb-twist throttle control device for vehicles includes a control device housing, a twist-type throttle control device mounted thereon which includes a rotatable handle and a thumb-type throttle control device mounted thereon generally adjacent the twist-type throttle control device, the thumb-type throttle control device including an outwardly-extending lever pivotably mounted on the control device housing. A throttle control device control mechanism is operatively interposed between the twist-type and the thumb-type throttle control device and the throttle of the vehicle and is operative to select one of the twist-type and the thumb-type throttle control device and to operatively connect the selected one of the twist-type and the thumb-type throttle control device to the throttle of the vehicle for operation thereof, with each control device being independently operable to control the throttle yet are not simultaneously operable, i.e. only one may control the throttle at any one time.

Description:
CROSS-REFERENCE TO RELATED PROVISIONAL PATENT  
       [0001]    This application claims priority based on a provisional patent, specifically on the Provisional Patent Application Ser. No. 60/721,815 filed Oct. 13, 2005. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]    1. Technical Field 
         [0003]    The present invention relates generally to throttle control devices and, more particularly, to a thumb/twist throttle control device which includes a twist-type throttle control device having a rotatable handle mounted on the handlebars of the motorized vehicle and a thumb-type throttle control device mounted adjacent to the twist-type throttle control device, the thumb-type throttle control device including a pivotally mounted lever, the twist-type throttle control device and thumb-type throttle control device each being independently operable to control the throttle of the motorized vehicle such that when the twist-type throttle control device is being used to operate the throttle, the thumb-type throttle control device is disengaged and when the thumb-type throttle control device is operating the throttle, the twist-type throttle control device is disengaged. 
         [0004]    2. Description of the Prior Art 
         [0005]    There has been an exponential increase in the number of personal recreational vehicles such as all-terrain vehicles for use on land and wave runner-type vehicles for use on the water. There are many reasons for this significant increase, but perhaps the most obvious reason is that these vehicles provide the operator with excitement, enjoyment, and freedom when they are using the vehicles. Another benefit of the vehicles is that they are relatively simple to use, in that the operator may merely sit on the vehicle and engage the throttle to power the vehicle and move the vehicle forward. Throttles and engines are of course well-known in the industry, and there are many different types of control devices for the throttle which are currently used. 
         [0006]    However, the most common type of throttle device used with such vehicles is known as the “thumb” throttle and generally includes a lever pivotally mounted on the handle bars of the vehicle, the lever mechanically operatively connected to the throttle in the engine of the vehicle such that rotation of the lever by the operator&#39;s thumb either increases or decreases the throttle valve opening to increase or decrease the power output by the engine. In general, the thumb throttle is an effective way to control the power output of the engine, but it has been found that use of the thumb throttle over an extended period of time is quite tiring and detracts from the enjoyment of use of the personal recreational vehicle. There is therefore a need for an alternative type of throttle that can be used with personal recreational vehicles in conjunction with the thumb throttle currently being used. 
         [0007]    Another type of common throttle device used in connection with motor vehicles is the twist throttle in which a rotatable handle is mounted on the end of the handlebar, the rotatable handle being connected through a mechanical operational mechanism to the throttle of the engine such that rotation of the rotatable handle either increases or decreases the throttle valve opening to increase or decrease power being output by the engine. Such twist-type throttles are commonly used in connection with motorcycles, but generally are not used in connection with personal recreational vehicles such as those described above. The main reason for this is that operation of a motorcycle generally does not involve the same degree of pitching and shifting of the handlebars as does operation of personal operational vehicles such as ATVs and wave runners and therefore it is far easier to restrict unintentional rotation of the twist-type throttle when using a motorcycle than if the twist-type throttle were the only throttle available on the personal recreational vehicle. However, there are many instances when the user of an ATV or wave runner is not in a situation where there is significant motion of the vehicle and it is at these times that a twist-type throttle would be useful for an operator of the personal recreational vehicle. There is therefore a need for a combination throttle which includes beneficial elements of both the twist-type throttle and the thumb-type throttle. 
         [0008]    Therefore, an object of the present invention is to provide a thumb-twist throttle control device for vehicles which will replace and improve upon the standard thumb throttles and twist throttles already in use. 
         [0009]    Another object of the present invention is to provide a thumb-twist throttle control device for vehicles which includes a housing, a twist-type throttle control device rotatably mounted on the housing, a thumb-type throttle control device pivotably mounted on the housing generally adjacent the twist-type throttle control device and a throttle control device control mechanism operative to alternatively operatively connect a selected one of the twist throttle or thumb throttle to the throttle of the vehicle for control thereof. 
         [0010]    Another object of the present invention is to provide a thumb-twist throttle control device for vehicles which will permit simple and quick switching between the twist-type throttle control device and the thumb-type throttle control device by the user of the present invention so that the user can use whichever throttle control is better suited for the current driving conditions. 
         [0011]    Another object of the present invention is to provide a thumb-twist throttle control device for vehicles which is usable with ATVs, personal watercraft and many other types of vehicles. 
         [0012]    Finally, an object of the present invention is to provide a thumb-twist throttle control device for vehicles which is relatively simple and durable in manufacture and design and which is safe, efficient and effective in use. 
       SUMMARY OF THE INVENTION  
       [0013]    The present invention provides a thumb-twist throttle control device for vehicles which includes a control device housing, a twist-type throttle control device mounted on the control device housing and extending outwards therefrom, the twist-type throttle control device including a rotatable handle which is rotatable about its center longitudinal axis, and a thumb-type throttle control device mounted on the control device housing generally adjacent the twist-type throttle control device, the thumb-type throttle control device including an outwardly-extending lever pivotably mounted on the control device housing. A throttle control device control mechanism is mounted within the control device housing and is operatively interposed between the twist-type throttle control device and the thumb-type throttle control device and the throttle of the vehicle on which the thumb-twist throttle control device is mounted, the throttle control device control mechanism operative to select one of the twist-type throttle control device and the thumb-type throttle control device and to operatively connect the selected one of the twist-type throttle control device and the thumb-type throttle control device to the throttle of the vehicle on which the thumb-twist throttle control device is mounted. Finally, the throttle control device control mechanism is further operative to selectively engage and connect the selected one of the twist-type throttle control device and the thumb-type throttle control device to the throttle of the vehicle on which the thumb-twist throttle control device is mounted such that each is independently operable to control the throttle and such that when the twist-type throttle control device is being used to operate the throttle, the thumb-type throttle control device is disengaged and when the thumb-type throttle control device is operating the throttle, the twist-type throttle control device is disengaged. 
         [0014]    The present invention thus provides an throttle control device which is superior in many respects to those devices currently found in the prior art. For example, the proximity of the thumb and twist throttle control devices permits use of whichever control device is desired by the user of the present invention. Furthermore, because the throttle controls are fixedly mounted on the handlebars of the vehicle, use of either throttle control device will provide a stable and solid support for the user of the vehicle. Finally, because the throttle control devices of the present invention are usable only in the alternative and not simultaneously, the safety factor for the present invention exceeds most other modified throttle devices found in the prior art. It is thus seen that the present invention provides a substantial improvement over those devices found in the prior art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0015]      FIG. 1  is a perspective view of an all-terrain vehicle outfitted with the thumb/twist throttle control device of the present invention; 
           [0016]      FIG. 2  is a perspective view of the thumb-twist throttle control device of the present invention; 
           [0017]      FIG. 3   a  is a detailed perspective view of one embodiment of the operating mechanism of the thumb-twist throttle control device; 
           [0018]      FIG. 3   b  is a detailed perspective view of a first alternative embodiment of the operational mechanism of the thumb/twist throttle control device of the present invention; 
           [0019]      FIG. 3   c  is a detailed perspective view of a second alternative embodiment of the operational mechanism of the thumb/twist throttle control device of the present invention; 
           [0020]      FIG. 4   a  is a detailed perspective view of the twist-type throttle control device section of the present invention; 
           [0021]      FIGS. 4   b,    4   c,  and  4   d  are, respectively, a detailed perspective view, a detailed side elevational view, and a detailed side elevational view of throttle control engagement mechanism of the present invention which permits the operator to switch between the twist-type throttle control device and thumb-type throttle control device; 
           [0022]      FIG. 5  is a perspective view of a third alternative embodiment of the operational mechanism of the thumb/twist throttle control device of the present invention; 
           [0023]      FIG. 6  is a detail exploded perspective view of the embodiment of  FIG. 5  showing the top portion of the thumb-twist throttle control device; 
           [0024]      FIG. 7  is a detail exploded perspective view of the embodiment of  FIG. 5  showing the bottom portion of the thumb-twist throttle control device; 
           [0025]      FIG. 8  is a detail exploded perspective view of the embodiment of  FIG. 5  showing the transmission and switching mechanism of the thumb-twist throttle control device; 
           [0026]      FIG. 9  is a detail top plan view of the embodiment of  FIG. 5  showing the transmission and switching mechanism of the thumb-twist throttle control device engaging the twist throttle control device; 
           [0027]      FIG. 10  is a detail side elevational view of the embodiment of  FIG. 5  showing the transmission and switching mechanism of the thumb-twist throttle control device being switched to engage the thumb throttle control device; 
           [0028]      FIG. 11  is a detail top plan view of the embodiment of  FIG. 5  showing the transmission and switching mechanism of the thumb-twist throttle control device engaging the thumb throttle control device; and 
           [0029]      FIG. 12  is a detail exploded perspective view of the embodiment of  FIG. 5  in which the mechanical switching mechanism is substituted by a solenoid for switching between the thumb and twist throttle control devices. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]    The thumb/twist throttle control device  10  of the present invention is shown best in  FIGS. 1-4   d  as including a twist-type throttle control device  20  and a thumb-type throttle control device  40  mounted adjacent to and below the twist-type throttle control device  20  and a throttle control device control mechanism  60  on which the twist-type throttle control device  20  and thumb-type throttle control device  40  are mounted. As shown best in  FIG. 2 , the thumb-twist throttle control device  10  would be mounted on the end of the handlebar  102  of the personal recreational vehicle  100 , in this case an ATV. It should be noted that the mounting of the thumb/twist throttle control device  10  on the handlebar  102  would preferably be done by extending the handlebar shaft into the thumb/twist throttle control device  10 , specifically into the twist-type throttle control device  20 , such that the twist-type throttle control device  20  is coaxially mounted on the handlebar  102  to provide a sturdy and safe connection and mounting for the thumb/twist throttle control device  10  of the present invention. Of course, however, the precise nature of the mounting of the thumb/twist throttle control device  10  on the personal recreational vehicle  100  is not critical so long as it is safely and securely mounted thereon. 
         [0031]    In the preferred embodiment, the twist-type throttle control device  20  would preferably include a rotatably mounted handle  22  which is generally cylindrical in shape and is mounted to rotate about its center longitudinal axis, as shown best in  FIG. 3   a.  Mounted on the inner end  24  of rotatably mounted handle  22  is a throttle cable engagement slot  26  mounted on cable pulley wheel  30  into which an end of the throttle cable  104  may be inserted such that rotation of the rotatable handle  22  rotates the throttle cable engagement slot  26 , thus tensioning the throttle cable  104  and operating the throttle of the personal recreational vehicle  100 . It should be noted that the exact size, shape, and construction materials used in connection with the rotatable handle  22  are not particularly critical to the present invention and will, to a large extent, depend on the preferences of the manufacturer and user of the present invention. 
         [0032]    The thumb-type throttle control device  40  is also shown best in  FIG. 3   a  as including a thumb lever  42  which is rotatably mounted beneath the twist-type throttle control device  20 , the inner end  44  of thumb lever  42  mounted on an upright shaft  46  which is pivotally mounted to permit the thumb lever  42  to rotate about the center longitudinal axis of the upright shaft  46 , as shown best in  FIG. 3   a.  In the preferred embodiment, the inner end  44  of thumb lever  42  is connected to the lower section of the upright shaft  46  and a throttle cable connection bar  48  is connected to and extends outwards from the upper end of the upright shaft  46  for connection to the throttle cable  104 , specifically a second extension section  108  of throttle cable  104 . As shown in  FIG. 3   a,  the second extension section  108  of throttle cable  104  would be connected to one end  50  of throttle cable connection bar  48  with the second extension section  108  of throttle cable  104  extending around a pair of pulleys  28  and  32 , with pulley  32  mounted on the inner end  24  of rotatable handle  22  of twist-type throttle control device  20 . In this manner, the connection of the second extension section  108  of throttle cable  104  to the thumb-type throttle control device  40  permits the thumb-type throttle control device  40  to operate the throttle and, likewise, the first extension section  106  of throttle cable  104  connected to the throttle cable engagement slot  24  of the twist-type throttle control device  20  permits the twist-type throttle control device  20  to also operate the throttle of the personal recreational vehicle  100 . 
         [0033]    To permit this alternate operation of the vehicle&#39;s throttle, one of several different types of mechanical connections between the first extension section  106 , second extension section  108 , and the throttle cable  104  itself may be employed, such as those shown in  FIGS. 3   a,    3   b,  and  3   c.  Specifically, the embodiment shown in  FIG. 3   a  would include a junction box  70  into which the first and second extension sections  106  and  108  of throttle cable  104  extend, with the throttle cable  104  itself extending out of the opposite end of the junction box  70 . The junction box  70  is operative to permit either the first extension section  106  or the second extension section  108  to tension the throttle cable  104 , thus controlling the opening of the throttle valve (not shown) of the personal recreational vehicle  100 . It should be noted that many different mechanical connections between the first extension section  106 , second extension section  108 , and throttle cable  104 , may be utilized with the present invention so long as the intended function of permitting either of the extension cables to operate the throttle cable  104  is maintained, but two variations of the junction box  70  are shown in  FIGS. 3   b  and  3   c  for illustrative purposes. 
         [0034]    Specifically,  FIG. 3   b  illustrates that the first and second extension sections  106  and  108  are actually parts of a single throttle cable control cable  72  which extends around a pulley  74  mounted within the junction box  70 . As the present invention is intended to be operated with only one or the other of the throttle control devices being engaged, when the twist-type throttle control device  20  is being utilized, the thumb-type throttle control device  40  is immobilized, and vice versa. Therefore, when the throttle cable control cable  72  is tensioned by rotation of the rotatable handle  22  of twist-type throttle control device  20 , it pulls the pulley  74  in the direction of first extension  106  as the opposite end of the throttle cable control cable  72  is fixed in position. Therefore, the operation of the throttle valve of the personal recreational vehicle  100  via the throttle cable  104  is performed solely by rotation of the twist-type throttle control device  20 , specifically the rotatable handle  22  of the twist-type throttle control device  20  which rotates the throttle cable engagement slot  26  mounted on cable pulley wheel  30 . Alternatively, when the thumb-type throttle control device  40  is being utilized, the rotation of the thumb lever  42  pivots the throttle cable connection bar  48  about upright shaft  46 , thus tensioning the second extension section  108  of throttle cable  104  and thereby pulling the throttle cable  104  towards the second extension section  108 . Because the rotatable handle  22  of twist-type throttle control device  20  is fixed in position, the thumb-type throttle control device  40  thus retains complete control over the opening and closing of the throttle valve of the personal recreational vehicle  100  via the throttle cable  104 . 
         [0035]      FIG. 3   c  illustrates an alternative embodiment of the junction box  70  in which there is a simple Y-plate  76  mounted within the junction box  70  to which the throttle cable  104 , first extension section  106 , and second extension section  108  are connected. When one or the other of the first and second extension sections  106  and  108  are tensioned, the Y-plate  76  transfers the tensioning force directly to the throttle cable  104  and the initiating throttle control device, be it the twist-type throttle control device  20  or thumb-type throttle control device  40 , thus retains control over operation of the throttle cable  104 . The only significant disadvantage of the embodiment of  FIG. 3   c  is that some degree of slack will be produced in whichever of the first and second extension sections  106  and  108  is not being used to tension the throttle cable  104 , but as the expected slack will be no more than one-half to one inch in length, it is expected that providing an appropriate location for the slack to be taken up into will be easily achieved. Finally, it should be noted that, as was discussed previously, numerous other types of mechanical connections may be made between the first and second extension sections  106  and  108  and throttle cable  104 , and numerous other types of connections may also be contemplated, such as electrical connections including “drive-by-wire” or the like may be incorporated into the thumb/twist throttle control device  10  of the present invention, specifically the junction box  70  which controls alternate operation of the throttle cable  104  by the twist-type throttle control device  20  and thumb-type throttle control device  40 , and such variations should be understood to be a part of this disclosure. 
         [0036]    Although the junction box  70  described above constitutes an important feature of the thumb/twist throttle control device  10  of the present invention, an even more important element of the present invention is shown in  FIGS. 4   a - 4   d,  specifically the throttle control device control mechanism  60  which will now be described. In general, the throttle control device control mechanism  60  is designed to prevent simultaneous engagement of the twist-type throttle control device  20  and thumb-type throttle control device  40 , in that the throttle control device control mechanism  60  prevents rotation of the rotatable handle  22  of twist-type throttle control device  20  when the thumb-type throttle control device  40  is operatively connected to throttle cable  104  and likewise, the throttle control device control mechanism  60  prevents operation of the thumb-type throttle control device  40 , specifically rotation of thumb lever  42 , when the twist-type throttle control device  20  is operatively connected to the throttle cable  104  and is in control of throttle operation. There are many different types of mechanisms which may be used to control and restrict simultaneous operation of the twist-type throttle control device  20  and thumb-type throttle control device  40 , but a preferred embodiment of the throttle control device control mechanism  60  is shown in  FIGS. 4   a,    4   b,    4   c,  and  4   d.    
         [0037]    Specifically, throttle control device control mechanism  60  would include a push button-type mechanism having a forward-facing push rod  80  which is movably mounted within the outer casing  62  of throttle control device control mechanism  60 , as shown best in  FIGS. 2 ,  4   a,  and  4   b,  which preferably covers and encloses the entire mechanism to prevent contaminants from degrading performance of the throttle control device control mechanism  60 . The forward end  82  of push rod  80  would extend forwards and outwards from outer casing  62  for engagement by a thumb or finger of the user of the present invention and push rod  80  will be movable along the longitudinal axis of push rod  80 , as shown best in  FIGS. 4   a  and  4   b.  Mounted on the rear end of push rod  80  is a downward-facing cam  84  which selectively engages a spring-loaded upright shaft  86  to depress the upright shaft  86  as cam  84  moves rearwards over the upright shaft  86 , as shown best in  FIG. 4   b.  Mounted adjacent the base of upright shaft  86  is a toggle bar  88  which rocks between a disengagement position when upright shaft  86  is not engaged by cam  84  and an engagement position when upright shaft  86  is depressed by cam  84 , as shown in  FIG. 4   c.  The toggle bar  88  is positioned to engage the underside of throttle cable connection bar  48  such that when toggle bar  88  is in the engagement position shown in  FIG. 4   c,  the throttle cable connection bar  48  is lifted out of engagement with the upright shaft  46  and thus rotation of thumb lever  42  of thumb-type throttle control device  40  does not result in operation of the throttle cable  104  via second extension section  108 . At the same time the throttle cable connection bar  48  is disengaged from the upright shaft  46 , the rotatable handle  22  is shifted into engagement with the throttle cable engagement slot  24  and the cable pulley wheel  30  thus permitting the throttle cable engagement slot  24  to operatively connect the rotatable handle  22  with the throttle cable  104 , as shown best in  FIG. 4   c.    
         [0038]    In the alternative, when the push rod  80  is extended forward, i.e. released, the cam  84  disengages from contact with the top of upright shaft  86  and thus the spring-loaded upright shaft  86  recoils upwards, thus releasing toggle bar  88  and dropping throttle cable connection bar  48  downwards to intermesh with upright shaft  46 . Simultaneously, the rotatable handle  22  of twist-type throttle control device  20  is moved outwards out of connection with throttle cable engagement slot  24  mounted on cable pulley wheel  30 , and thus the rotatable handle  22  no longer is operatively connected to the throttle cable  104 . Rather, it is the thumb lever  42  of thumb-type throttle control device  40  which is operatively connected to the throttle cable  104  via second extension section  108 , as shown best in  FIG. 4   d.  The specific mechanism operative to disengage rotatable handle  22  from throttle cable engagement slot  24  is shown in  FIG. 4   a  as a concave cam section  83  formed on push rod  80 , although the exact design of the disengagement mechanism for rotatable handle  22  will likely be modified depending on the precise structure used in connection with the present invention. In this manner, the alternate engagement of the twist-type throttle control device  20  and thumb-type throttle control device  40  is permitted and simultaneous operation of the two throttle control devices is prevented. 
         [0039]    A fourth embodiment of the thumb/twist throttle control device  10 ′ is shown best in  FIGS. 5-12  as including a control device housing  200  which fits onto and over the handlebar  102  and which further includes a lower section  202  and an upper section  204  connected to one another by bolts or the like, the upper section  204  further including a top plate  206  which can be removed to provide access to the internal elements of the device. The throttle control device  210  of this embodiment would preferably include a throttle cable pulley  212  around which the throttle cable  104  would travel as it enters the throttle control device  210 . 
         [0040]    The throttle control device  210  is best shown in  FIGS. 5-8  as including a twist-type throttle control device  20 ′ which includes a twist throttle base cylinder  220  which fits over the handlebar  102  and is rotatably mounted on the control device housing  200 , the twist throttle base cylinder  220  including a rubber grip  222  mounted on the outer surface thereof, an inner section  226  which is rotatably housed within the control device housing  200 , and several slots  224  which extend longitudinally through inner section  226  from the inner end thereof. The slots  224  extend generally radially from the center longitudinal axis of the twist throttle base cylinder  220  and their purpose will be discussed later in this disclosure. In the preferred embodiment, the twist throttle base cylinder  220  would have dimensions similar to the rotatably mounted handle  22  described previously. 
         [0041]    It is important to note that the handlebar  102  extends through the entire control device housing  200  and thus provides the support structure for each of the elements of the throttle control device  210 , and therefore when the interaction between elements is being described herein, it is to be understood that sliding and rotational movement of the elements occurs on the handlebar  102 . That being said, the throttle cable engagement spline  230  is positioned adjacent to and in concentric alignment with the twist throttle base cylinder  220 , and in the preferred embodiment, the throttle cable engagement spline  230  would be a partial ring of metal or plastic material which includes a cable engagement recess  232  formed on one end thereof, a cable channel  236  formed in the outer surface of the throttle cable engagement spline  230  and which extends circumferentially around the throttle cable engagement spline  230 , and several slots  234  which are of the same size and shape and are initially generally aligned with the slots  224  formed in the inner section  226  of the twist throttle base cylinder  220 . The throttle cable engagement spline  230  engages the cable connector  105  which is mounted on the end of the throttle cable  104  via the cable engagement recess  232  such that as the throttle cable engagement spline  230  is rotated, the throttle cable  104  is alternatively tensioned and released to control the throttle of the vehicle. 
         [0042]    Mounted adjacent to the throttle cable engagement spline  230  in concentric alignment therewith is the thumb lever engagement spline  240 , which, in the preferred embodiment, is a ring constructed of metal or plastic which includes a thumb lever attachment hole  242  and several slots  244  which are of the same size and shape of the slots  224  formed in the inner section  226  of the twist throttle base cylinder  220 . The thumb lever engagement spline  240  is positioned on the opposite side of the throttle cable engagement spline  230  from the twist throttle base cylinder  220 , as shown best in  FIGS. 7 and 8 , and the thumb lever engagement spline is operatively connected to the thumb-type throttle control device  40 ′ as shown best in  FIGS. 7 ,  9  and  11 . Specifically, the thumb throttle lever  290  is mounted on thumb throttle shaft  292  which is rotatably mounted in the lower section  202  of the control device housing  200  and extends upwards therethrough. A shaft arm  294  extends generally perpendicularly outwards from the thumb throttle shaft  292  and a connection arm  296  extends between and connects the outer end of the shaft arm  294  and the thumb lever attachment hole  242  on the thumb lever engagement spline  240  to complete the connection between the thumb-type throttle control device  40 ′ and the thumb lever engagement spline  240 . In this manner, rotation of the thumb throttle lever  290  results in rotation of the thumb lever engagement spline  240  in direct proportion to the movement of the thumb throttle lever  290 . 
         [0043]    The mechanism for switching between the twist-type throttle control device  20 ′ and thumb-type throttle control device  40 ′ will now be described. A throttle selector transmission section  250  includes a throttle selector transmission cylinder  252  which, in the preferred embodiment, would be a metal or plastic cylinder having an inner diameter slightly greater than the outer diameter of the handlebar  102  such that the throttle selector transmission cylinder  252  may slide back and forth on the handlebar  102 , as shown best in  FIGS. 9 ,  10  and  11 . Projecting outwards from the engagement end of the throttle selector transmission cylinder  252  generally perpendicular to the center longitudinal axis of the throttle selector transmission cylinder  252  are several transmission tabs  254  which are of a size and shape as to fit within each of the several slots  224 ,  234  and  244  found on the twist throttle base cylinder  220 , throttle cable engagement spline  230  and the thumb lever engagement spline  240 . In operation, the throttle selector transmission cylinder  252  would slide back and forth, and the length of each of the transmission tabs  254  is such that when the throttle selector transmission cylinder  250  is farthest towards the twist throttle base cylinder  220 , as shown in  FIG. 9 , the transmission tabs  254  each engage the slots  224  and  234  on the twist throttle base cylinder  220  and throttle cable engagement spline  230  but do not engage the slots  244  on the thumb lever engagement spline  240 . This causes the twist throttle base cylinder  220  and the throttle cable engagement spline  230  to rotate in unison, and therefore rotation of the twist throttle base cylinder  220  results in rotation of the throttle cable engagement spline  230 . This, of course, means that the twist-type throttle control device  20 ′ will control the operation of the throttle of the vehicle when the throttle selector transmission cylinder  250  is positioned towards and adjacent the inner section  226  of the twist throttle base cylinder  220 . 
         [0044]    Conversely, when the throttle selector transmission cylinder  250  is positioned farthest away from the inner section  226  of the twist throttle base cylinder  220 , as shown in  FIG. 11 , the transmission tabs  254  engage the several slots  234  and  244  on the throttle cable engagement spline  230  and the thumb lever engagement spline  240  but do not engage the slots  224  on the twist throttle base cylinder  220 . This causes the throttle cable engagement spline  230  and the thumb lever engagement spline  240  to rotate in unison, and therefore rotation of the thumb lever engagement spline  240  results in rotation of the throttle cable engagement spline  230 . This, of course, means that the thumb-type throttle control device  40 ′ will control the operation of the throttle of the vehicle when the throttle selector transmission cylinder  250  is positioned farthest away from the inner section  226  of the twist throttle base cylinder  220 . 
         [0045]    The throttle control selection mechanism  270  is shown best in  FIGS. 6 and 10  as including a throttle selector input shaft  272  which extends generally horizontally through the control device housing  200  and is rotatable about its center longitudinal axis. Mounted on the throttle selector input shaft  272  inside the control device housing  200  is a shaft collar  276 , and mounted on the throttle selector input shaft  272  externally of the control device housing  200  is a selector lever  274  which may be manipulated to rotate the throttle selector input shaft  272 . Mounted on and extending outwards from the shaft collar  276  is a selector arm  278  which provides the mechanical translation to permit the rotation of the throttle selector input shaft  272  to shift the position of the throttle selector transmission cylinder  250 . 
         [0046]    A shift ring  260  is mounted on the throttle selector transmission cylinder  252  by a pair of shift ring securement tabs  264  which extend into a shift ring engagement channel  256  formed at the far end of the throttle selector transmission cylinder  252  as shown best in  FIG. 10 , and the selector arm  278  is connected to one side of the shift ring  260 . The opposite side of the shift ring  260  includes a pivot tab  262  which extends into an opening formed in the lower section  202  as shown in  FIG. 9 , thus allowing the shift ring  260  to pivot and move the throttle selector transmission cylinder  252  therewith as the shift ring  260  pivots. Rotation of the throttle selector input shaft  272  causes the selector arm  278  to pivot the shift ring  260  thereby moving the throttle selector transmission cylinder  252  between the positions as described previously. 
         [0047]    Also, it may be important to include a twist throttle stop device  280  which will prevent rotation of the twist-type throttle control device  20  upon engagement thereof. This will prevent unintentional rotation of the twist-type throttle control device  20  when the thumb-type throttle control device  40  is engaged which is important for safety purposes. Briefly, the twist throttle stop device  280  is shown best in  FIGS. 6 and 10  as including a rotating stop shaft  284  on which is mounted a stop bar  282  which engages the inner section  226  of the twist throttle base cylinder  220  when the stop shaft is rotated as shown in  FIG. 10 . A torsion spring  286  biases the stop shaft  284  to rotate into the stop position, but when the throttle selector transmission cylinder  252  is adjacent the twist throttle base cylinder  220  as shown in  FIG. 9 , the throttle selector transmission cylinder  252  physically moves the twist throttle stop device  280  out of the stop position thus allowing the twist throttle base cylinder  220  to rotate. When the throttle selector transmission cylinder  252  moves away from the twist throttle base cylinder  220 , however, the torsion spring  286  biases the stop shaft  284  to rotate into the stop position such that the stop bar  282  engages the inner section  226  of the twist throttle base cylinder  220  thus preventing unauthorized rotation of the twist throttle base cylinder  220 . 
         [0048]    The user of the present invention may thus quickly and easily shift between the twist-type throttle control device  20 ′ and the thumb-type throttle control device  40 ′ for operation of the throttle of the vehicle by simply rotating the selector lever  274  to rotate the throttle selector input shaft  272  thus moving the throttle selector transmission cylinder  252  between the engagement position for the twist-type throttle control device  20 ′ and the engagement position for the thumb-type throttle control device  40 ′. Alternatively, instead of providing a mechanical device such as the selector lever  274  and the throttle selector input shaft  272 , it may be preferable to include a solenoid  300  or another such electrically activated force-producing device which is operatively connected to the throttle selector transmission cylinder  252  via a solenoid connection tab  258 , as shown in  FIG. 12 . A selector button would be provided on the exterior of the control device housing  200  for operating the solenoid  300 , which would cause the solenoid piston  302  to fire or retract thus shifting the throttle selector transmission cylinder  252  as was described previously. It is believed that by utilizing such an electronic shifting mechanism, the mechanical complexity of the present invention may be significantly decreased, thereby lessening the opportunity for mechanical breakdown and thus likely increasing the reliability and longevity of the present invention. Of course, many different types of electrical and mechanical force-producing devices may be substituted for the devices described herein, and such substitution should be understood to be a part of this disclosure and invention. 
         [0049]    There are several additional features which may be incorporated into the thumb/twist throttle control device  10  of the present invention which will facilitate operation and use of the present invention. Specifically, in one preferred embodiment, it may be desirable to have the thumb lever  42  rotate out of the way of operation of the twist-type throttle control device  20  when the thumb-type throttle control device  40  is disengaged, and it will be a relatively simple matter to include a rotating cam or gear assembly to facilitate such rotation of the thumb lever  42 . Furthermore, the precise placement of the various pulleys of the present invention may be modified or changed depending upon the orientation and arrangement of the elements of the thumb/twist throttle control device  10  of the present invention, and such modification are well within the purview of the present disclosure and so long as the throttle cable  104 . Also, it is important to note that while the thumb/twist throttle control device  10  has been described with some particularity, many variations of the operative elements described may be incorporated into the present invention so long as the intended general function of providing either a twist-type throttle control device  20  or a thumb-type throttle control device  40  in a single coordinated unit is maintained. Therefore, it is to be understood that numerous additions, substitutions and modifications may be made to the thumb/twist throttle control device  10  of the present invention which fall within the intended broad scope of the above description. 
         [0050]    There has therefore been shown and described a thumb/twist throttle control device  10  which accomplishes at least all of its intended objectives.