Abstract:
A motorcycle ( 10 ) has a foot-operated accelerator pedal ( 32 ) for operating the throttle ( 58 ) of the engine ( 12 ). The pedal ( 32 ) and an adjacent brake pedal ( 34 ) have shapes correlated to not interfere with each other when they are depressed. The pedals may be provided as original equipment, or retrofitted to an existing motorcycle that has a hand-operated throttle controller.

Description:
FIELD OF THE INVENTION 
     This invention relates to motor-driven cycles, particularly to a control for the throttle of the engine. 
     BACKGROUND OF THE INVENTION 
     A motorcycle is one type of wheeled cycle that is operated by the coordinated use of hand and foot controls. It is typical to have the clutch lever mounted on the left side of the handlebars for actuation by the operator&#39;s left hand, and to have the front brake lever and the hand throttle control mounted on the right side of the handlebars for actuation by the operator&#39;s right hand to operate the front wheel brake and the engine throttle respectively. The transmission shift lever, or shift pedal, is typically located at the lower left side of the motorcycle on the transmission where it can be operated by the operator&#39;s left foot to shift transmission gears. The rear brake pedal is typically located at the lower right side of the motorcycle where it can be depressed by the operator&#39;s right foot to apply the rear wheel brake. 
     SUMMARY OF THE INVENTION 
     The inventors have discovered that the incorporation of a foot-operated throttle control in a motorcycle provides a control feature that is useful in certain driving situations. Using a foot-operated throttle can also create a different driving experience for an operator in comparison to using a hand throttle. 
     Principles of the invention can be applied to the design and manufacture of new motor-driven cycles by an O.E.M. The inventors also believe that marketing opportunities exist for retrofitting existing motorcycles because many motorcycle owners would appreciate the opportunity to retrofit their motorcycles with foot-operated throttle controls and because many motorcycle dealers would like to give customers a sales option of adding foot-operated throttle control to equipping a motorcycle having only a hand-operated throttle control. 
     Accordingly, principles of the invention relate not just to the incorporation of a foot-operated throttle control in a motorcycle regardless of whether the motorcycle is new or used, but also to a kit and method for retrofitting an existing motorcycle lacking foot-operated throttle control to integrate a foot-operated control with an existing hand-operated throttle control. 
     One generic aspect of the present invention relates to a motor-driven cycle comprising an engine controlled by a throttle that is operated by a throttle control turning a throttle lever on the exterior of the throttle body, wherein the throttle control comprises a connection operatively connecting a foot-operated accelerator pedal with the throttle lever to cause the throttle lever to turn when an operator&#39;s foot depresses the accelerator pedal. 
     In a preferred embodiment of the invention, the connection comprises a cable. 
     Another generic aspect relates to a kit for retrofitting a motorcycle with a foot-operated throttle. 
     The kit includes at least an accelerator pedal and a brake pedal each having a respective pedal arm and a respective foot pad at an end of the respective pedal arm. The opposite end of each arm has a through-hole for enabling the pedals to fit onto a common mounting shaft of a motorcycle. The pedals are arranged such that when installed adjacent each other on the mounting shaft and operatively connected with a wheel brake and the throttle lever respectively, the pedals are free of interference with each other as their respective foot pads are depressed to operate the wheel brake and engine throttle respectively over their respective ranges of travel. When viewed in the direction of the shaft axis, the range of travel of the accelerator pedal does not overlap the range of travel of the brake pedal, the foot pad of the accelerator pedal is always closer to an underlying footboard than is the foot pad of the brake pedal to the footboard, and the foot pad of the accelerator pedal extends further outboard than does the foot pad of the brake pedal. 
     Still another generic aspect relates to a method of retrofitting a foot-operated accelerator pedal to a motorcycle that has a foot-operated brake pedal arranged on a generally horizontal mounting shaft extending laterally outward from the chassis of the motorcycle to swing about an axis of the shaft for operating a wheel brake when a foot pad on an arm of the brake pedal is depressed. 
     The method comprises disconnecting the brake pedal from operative connection with the wheel brake and removing it from the mounting shaft, installing on the mounting shaft a brake pedal that has a shape different from that of the removed brake pedal and operatively connecting it with the wheel brake, installing on the mounting shaft adjacent the just-installed brake pedal an accelerator pedal having a shape correlated with that of the adjacent brake pedal, and operatively connecting the installed accelerator pedal with a throttle of an engine that propels the motorcycle. 
     The correlation of the shape of the accelerator pedal with that of the adjacent brake pedal places the pedals free of interference with each other as they are depressed about the shaft axis over respective ranges of travel to operate the wheel brake and engine throttle respectively. When viewed in the direction of the shaft axis, the range of travel of the accelerator pedal about the shaft axis is closer to an underlying footboard of the motorcycle than is that of the adjacent brake pedal, and an accelerator pedal foot pad via which the accelerator pedal is depressed extends further outboard than does a foot pad of the brake pedal via which the brake pedal is depressed. 
     The foregoing, along with further features and advantages of the invention, will be seen in the following disclosure of a presently preferred embodiment of the invention depicting the best mode contemplated at this time for carrying out the invention. This specification includes drawings, now briefly described as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a fragmentary perspective view, looking generally downward and inward, at the right side of a known motorcycle in the vicinity of the footboard. 
         FIG. 2  is a fragmentary perspective view, from a slightly different direction, of the right side of the motorcycle after it has been retrofitted with a foot-operated throttle control in accordance with principles of the present invention. 
         FIG. 3  is a fragmentary perspective view, similar to  FIG. 2 , but from a different direction. 
         FIG. 4  is a fragmentary perspective view, similar to  FIG. 3 , but from a slightly different direction. 
         FIG. 5  is another fragmentary perspective view but in the direction of arrow  5  in  FIG. 2 . 
         FIG. 6  is a schematic diagram of a throttle and associated throttle lever showing various cable connections to the lever. 
         FIG. 7  is a schematic diagram illustrating certain principles of the invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  shows a portion of an existing motorcycle  10  that is relevant to the explanation of how principles of the present invention are applied to retrofit motorcycle  10  with a foot-operated accelerator pedal as will be explained with reference to the later Figures. 
     Motorcycle  10  comprises a chassis that supports an engine  12  at a location between front and rear wheels (not shown) and generally below the operator&#39;s seat (also not shown). A generally horizontal mounting shaft  14  extends laterally outward from the chassis below an exhaust pipe  16  coming from engine  12 . A brake pedal  18  is arranged to turn about the axis (reference numeral  48  in later Figures) of shaft  14 . 
     Brake pedal  18  comprises a pedal arm  22  having a proximal end that journals the brake pedal on shaft  14  and an opposite distal end to which is joined a foot pad  24  via which an operator&#39;s foot can depress the brake pedal to apply a rear wheel brake for braking the rear wheel.  FIG. 1  shows brake pedal  18  in non-applied position. 
     A footboard  26  is supported on the chassis by front and rear brackets  28 ,  30 . Only bracket  30  is shown in  FIG. 1 ; bracket  28  is shown in  FIG. 5 . The footboard is laterally outward of pedal arm  22  in relation to where the pedal arm is journaled on shaft  14 . Pedal arm  22  has an intermediate bend that places a more distal portion of the arm further outboard of the chassis. 
     Footboard  26  provides a rest for the right foot of the motorcycle operator. When the operator applies the rear wheel brake, his/her foot is moved to push on foot pad  24 , depressing brake pedal  18  in the process. 
     Engine  12  also has a throttle that is not seen in  FIG. 1 . The throttle has a throttle lever that is operated by a throttle control (also not seen in  FIG. 1 ). The throttle control comprises one or more cables connecting a hand-operated throttle controller on the handlebars with the throttle lever to cause the throttle lever to turn in a correlation with operation of the controller. 
       FIG. 2  shows a presently preferred embodiment of the invention that incorporates a foot-operated accelerator pedal  32  in motorcycle  10 . Pedal  32  has a shape correlated with that of a foot-operated brake pedal  34  that operates the rear wheel brake of the motorcycle in the same way as brake pedal  18 . Both pedals  32 ,  34  are arranged immediately adjacent each other on shaft  14 , with pedal  32  outboard of pedal  34 . 
     Accelerator pedal  32  comprises a pedal arm  36  having a proximal end that journals the accelerator pedal on shaft  14  and an opposite distal end to which is joined a foot pad  38  via which the operator can depress the accelerator pedal. 
     Brake pedal  34  comprises a pedal arm  40  having a proximal end that journals the brake pedal on shaft  14  and an opposite distal end to which is joined a foot pad  42  via which the operator can depress the brake pedal. 
     An operative connection from accelerator pedal  32  to the engine throttle comprises a cable  44  one end of which is fixed to pedal  32 . Pedal  32  comprises a cam  46  arranged on pedal arm  36  radially of the axis  48  of shaft  14  to turn with the accelerator pedal. The one end of cable  44  attached to pedal arm  36  is tethered at a location that, as accelerator pedal  32  is depressed, pulls cable  44 , causing the cable to wrap onto a cam track, or groove, in cam  46 , pulling the cable in the process. Beyond cam  46  relative to axis  48 , cable  44  is guided by a cable guide  50  that is fastened via a bracket  52  to footboard mounting bracket  28 . Beyond cable guide  50 , cable  44  runs through a sheath  54  that is routed to the throttle. 
       FIG. 6  shows that upon exiting the sheath near the throttle  58 , cable  44  attaches to a throttle lever  60  on the exterior of the body of throttle  58 . In particular, cable  44  attaches to the throttle lever at a post  62  to which an actuator (not shown) from a cruise control unit (not shown) can also attach.  FIG. 6  also shows cables  64 ,  66  from the hand throttle connecting to lever  60 . 
     A bracket  67  is mounted on the motorcycle to locate sheath  54  so that cable  44  approaches lever  60  from generally the same direction as does cable  64 . 
     While lever  60  has been referred to here as the throttle lever, the actual construction may comprise two separate lever parts that are joined together and fixed to the throttle shaft. In such a construction, cable  44  attaches to one lever part, as shown, and cables  64 ,  66  attach to the other lever part, which is not specifically shown in  FIG. 6 , but is behind the part shown. 
       FIG. 6  shows lever  60  in idle position. When either cable  64  or cable  44  pulls on the lever, the lever turns about the throttle shaft axis  61  in the clockwise direction. With the engine running at idle, such motion will accelerate the engine. Coils of a torsional return spring (not shown in  FIG. 6 ) are disposed around the shaft on the exterior of the throttle body. The tails of the spring engage the throttle body and the throttle lever respectively to bias the throttle shaft toward idle position. 
     Cable  44  passes through a hole in post  62 , and the far end of the cable has a stop, such as a ball, that interferes with the post so that when the operator depresses accelerator pedal  32  to pull on the cable, the cable will not be pulled through the hole, but rather will turn lever  60 . This manner of connecting cable  44  with the throttle lever provides a lost motion connection that allows the cable to slide through the hole in post  62  when lever  60  is being turned by the hand throttle so that the presence of the accelerator pedal and its connection to the throttle lever don&#39;t interfere with operation of the hand throttle. 
       FIGS. 2 ,  3 , and  4  show both accelerator pedal  32  and brake pedal  34  in non-depressed positions. The non-depressed position of accelerator pedal  32  corresponds to idle position of throttle  58 . A torsion spring  68  that comprises coils  70  disposed about shaft  14  urges pedal  32  to that position by having one tail  72  of the spring hooked under the pedal as shown and the other tail  74  hooked under bracket  30 . 
     The hand controller has a similar biasing, and when neither it nor accelerator pedal  32  is being actuated, throttle lever  60  assumes idle position to place the throttle in idle. Because the hand controller and the accelerator pedal can be actuated independently of each other, actuation of either one will turn lever  60  in a corresponding amount. When the hand controller is actuated to open the throttle, lever  60  turns in a way that doesn&#39;t pull on the cable from a cruise control unit connected to post  62 . By connecting cable  44  to post  62 , pedal  32  is not depressed by actuation of the hand controller. 
     However, when the cruise control is active, it will move the hand controller. Consequently, when accelerator pedal  32  is depressed, it too will move the hand controller. 
     Pedals  32 ,  34  are arranged to be free of interference with each other as their respective foot pads  38 ,  42  are depressed.  FIG. 7  shows that the range of travel  76  of accelerator pedal  32  about axis  48  does not overlap the range of travel  78  of the brake pedal. Foot pad  38  of the accelerator pedal is always closer to footboard  26  than is foot pad  42  of brake pedal  34  to the footboard.  FIG. 2  shows that foot pad  38  extends further outboard of the motorcycle than does foot pad  42 . 
       FIGS. 2-7  show what may be either an O.E.M. installation or a retrofit using a kit. Such a kit comprises at least pedals  32 ,  34 . The kit preferably also includes spring  68 , cable  44  and its sheath, cable guide  50 , and bracket  52 . 
     The retrofit of the existing motorcycle  10  shown in  FIG. 1  is performed by removing footboard  26  from its mounting brackets to provide more convenient access to a nut  80  that is holding pedal  18  on shaft  14 , and then unscrewing the nut. Pedal  18  is disconnected from the connection to the rear wheel brake and removed. The two replacement pedals  32 ,  34  are placed on shaft  14 , pedal  34  first. Spring  68  is put in place at the same time. Nut  80  is then screwed back onto the shaft, and pedal  34  is connected to the connection to the rear wheel brake. Bracket  52  is attached to bracket  28 , and the sheathed cable is routed to the throttle where cable  44  is connected to post  62  on lever  60 . Finally the footboard is re-installed. 
     From the foregoing, the reader can understand that the invention has various advantageous aspects. While a presently preferred embodiment has been illustrated and described, it is to be appreciated that the inventive principles are applicable to other embodiments within the scope of the following claims that define the inventive subject matter.