Abstract:
A manual operator for a vehicle, wherein the manual operator can be simply operated, has a good appearance, and allows a sufficient space for a manual operator for a parking brake. A first manual operator ( 13 ) pivotably mounted on a handlebar ( 11 ) has an output section ( 26 ) mounted so as to be pivotable about the center of a first support shaft ( 12 ). A second manual operator ( 15 ) has an input section ( 44 ) provided so as to be pivotable about a second support shaft ( 14 ) when pushed by the output section ( 26 ). The second manual operator ( 15 ) is a manual operator adapted for a vehicle parking brake and capable of setting the vehicle to a parked state.

Description:
TECHNICAL FIELD 
     The present invention relates to an improvement in a manually operable mechanism for a vehicle. 
     BACKGROUND ART 
     A parking lever disposed in the vicinity of a grip of a handlebar of a motorcycle is known from, for example, Patent Literature 1 and 2. 
     The parking lever disclosed in Patent Literature 1 is pivotably provided in the vicinity of a left grip of a handlebar of a motorcycle. The parking lever is connected via a parking lever cable to a parking brake mechanism provided in a rear wheel of the motorcycle. When the parking lever is in a non-operated position located away from the left grip, a parking brake is released. When the parking lever pivots to an operated position located along the length of the left grip, the parking brake mechanism is actuated to apply the parking brake. When a driver starts the vehicle with the parking lever in the operated position, he grips the left grip. By gripping the left grip, he identifies the parking lever located along the left grip and remembers to release the parking brake before starting the vehicle. 
     For releasing the parking brake, the driver must manually operate the parking lever for pivotal movement of the parking lever from the operated position to the non-operated position. However, he would undesirably spend a lot of time and effort on such a manual operation of the parking lever before starting the vehicle. 
     Patent Literature 2 discloses a parking lever vertically pivotable on a horizontal support shaft extending longitudinally of a vehicle, and an operational lever (a clutch lever) horizontally pivotable on a vertical support shaft. The parking lever is disposed between the operational lever and a handlebar. When the operational lever is horizontally pivoted on the vertical support shaft towards the handlebar, a distal end portion of the operational lever presses a releasing portion of the parking lever to cause vertical pivotal movement of the parking lever on the horizontal support shaft for releasing a parking brake. That is, the operational lever and the parking lever are designed to provide a specific structure for converting a force causing the horizontal pivotal movement of the operational lever into a force causing the vertical pivotal movement of the parking lever. 
     The provision of such a specific structure undesirably results in an increased cost of components of the operational lever and the parking lever. Furthermore, the conversion of the force causing the horizontal pivotal movement of the operational lever into the force causing the vertical pivotal movement of the parking lever may not be smoothly made. 
     In addition, since the parking lever is disposed on the operational lever, the vertical pivotal movement of the parking lever provides unpleasant appearance. To make the appearance of the parking lever inconspicuous, one may propose downsizing the parking lever. However, operation of the downsized parking lever requires a great force. 
     There is a need to provide a mechanism for a parking brake of a vehicle, which mechanism includes a simple structure that can be operated in a short time in such a manner as to achieve smooth force conversion. 
     PRIOR ART LITERATURE 
     Patent Literature 
     
         
         Patent Literature 1: Japanese Patent Application Laid-Open Publication No. 2001-63675 
         Patent Literature 2: Japanese Patent Application Laid-Open Publication No. 2004-279649 
       
    
     SUMMARY OF INVENTION 
     It is therefore an object of the present invention to provide a mechanism for a parking brake of a vehicle, which mechanism includes a simple structure that can be operated in a short time in such a manner as to achieve smooth force conversion. 
     According to an aspect of the present invention, there is provided a manually operable mechanism for a vehicle having a handlebar to be operated by an operator for steering the vehicle, which mechanism comprises: a first manual operation member pivotably attached to the handlebar through a first support shaft, the first manual operation member being operable by the operator to pivot on the first support shaft; a second manual operation member pivotably attached to the handlebar through a second support shaft disposed in the vicinity of and in parallel to the first support shaft; and the first manual operation member having an output portion, the second manual operation member having an input portion to be pressed by the output portion of the first operation member during pivotal movement of the first manual operation member on the first support shaft such that the second manual operation member pivots on the second support shaft. 
     In a preferred form of the invention, the second manual operation member is pivotable between an operated position and a non-operated position, and wherein, when the second manual operation member is in the operated position, the second manual operation member is urged by a predetermined urging force in a direction opposite to a direction toward the non-operated position, and when the second manual operation member pivots towards the non-operated position through a given angle, the second manual operation member is urged by the urging force in the direction toward the non-operated position. 
     Preferably, the first manual operation member, the second manual operation member and the second support shaft are disposed such that, when the first manual operation member pivots against the urging force through an angle smaller than a predetermined angle, the second manual operation member is pivoted by the output portion of the first manual operation member pressing the input portion of the second manual operation member, and when the first manual operation member pivots through an angle larger than the predetermined angle, the second manual operation member is pivoted by the urging force urging the second manual operation member in the direction toward the non-operated position and the input portion of the second manual operation member moves away from the output portion of the first manual operation member so as to allow the second manual operation member to pivot independently of the first manual operation member. 
     In a further preferred form of the invention, the second manual operation member comprises a parking brake operated to hold the vehicle in a parked state. 
     The first manual operation member has the output portion formed integrally therewith and the second manual operation member has the input portion formed integrally therewith. The input portion is pressed by the output portion during the pivotal movement of the first manual operation member on the first manual support shaft such that the second manual operation member pivots on the second support shaft. Since operation of the first manual operation member moves the second manual operation member, the parking brake can be readily released. 
     When the first manual operation member is pivoted through the angle larger than the predetermined angle, the second manual operation member is urged by the urging force in such a direction as to release the parking brake and the input portion moves away from the output portion so as to allow the second manual operation member to pivot independently of the first manual operation member. After the second manual operation member is pivoted independently of the first manual operation member, the first manual operation member is pivotable independently, which is useful for an operator. 
     The size of the second manual operation member may be freely set. Thus, the second manual operation member may have a large size. 
     Preferably, the first manual operation member, the first support shaft and the second support shaft are disposed forward of the handlebar when the vehicle is viewed in top plan, and wherein, when a parking brake is released, the second manual operation member is located rearward of a front edge of the first manual operation member and forward of a rear edge of the handlebar in such a manner that a distal end of the second manual operation member does not interfere with a range of movement of an operational portion of the first manual operation member. 
     When the parking brake is released, the distal end portion of the second manual operation member is located without interfering with the range of the movement of the operational portion of the first manual operation member. It becomes possible to prevent the operator from unintentionally operating the second manual operation member when he operates the first manual operation member. That is, the operator may easily operate the first manual operation member because he is not subject to constraints attributed to the second manual operation member in operating the first manual operation member. The second manual operation member is disposed rearward of the front edge of the first manual operation member and forward of the rear edge of the handlebar, which makes the second manual operation member inconspicuous for improved appearance of the second manual operation member. 
     In a preferred form of the invention, the second manual operation member is pivotable between an operated position to apply a parking brake and a non-operated position to release the parking brake, and wherein the output portion of the first manual operation member and the input portion of the second manual operation member are disposed in such a manner as to prevent the second manual operation member from pivoting to the operated position when the first manual operation member is operated by a maximum amount. 
     In other words, it becomes possible to prevent the second manual operation member from pivoting to the operated position during operation of the first manual operation member. 
     In a further preferred form of the invention, the output portion of the first manual operation member provides a first turning radius defined as a distance between the output portion and the first support shaft, and the input portion of the second manual operation member provides a second turning radius defined as a distance between the input portion and the second support shaft, the first radius being larger than the second radius. 
     A small amount of the pivotal movement of the first manual operation member makes a large amount of the pivotal movement of the second manual operation member. 
     In a still further preferred form of the invention, the second manual operation member is disposed in such a manner as to pivot on the second support shaft within a range that does not extend rearward beyond a rear face of an auxiliary member attached to the handlebar when the vehicle is viewed in top plan. 
     The second manual operation member thus arranged does not provide an obstruction to the operator. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a side view showing a vehicle including a manually operable mechanism in accordance with the present invention; 
         FIG. 2  is a top plan view of the manually operable mechanism shown in  FIG. 1 ; 
         FIG. 3  is an exploded perspective view showing the manually operable mechanism shown in  FIG. 2 ; 
         FIG. 4  is a view showing a relation between a second manual operation member and an upper bracket; 
         FIG. 5  is the view of  FIG. 4  with the second manual operation member pivoted to an operated position to apply a parking brake; 
         FIG. 6  is a view showing the second manual operation member in the operated position; 
         FIG. 7  is a view showing a first manual operation member pivoted in such a direction as to move the second manual operation member to a non-operated position to release the parking brake; 
         FIG. 8  is a view showing the first manual operation member pressing the second manual operation member in a direction towards the non-operated position; and 
         FIG. 9  is a view showing an alternative to the second manual operation member shown in  FIG. 7 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Certain preferred embodiments will be discussed below with reference to the accompanying drawings. 
     Referring to  FIG. 1 , there is shown a straddle-type vehicle for motorcycle)  1  arranged such that a driver sits on a seat  7  of the vehicle  1  with his legs positioned astride of the seat  7 . The vehicle  1  includes a vehicle body frame  2 , a front wheel  3  positioned forward of the frame  2  and a rear wheel  4  positioned rearward of the frame  2 . Attached to the center of the frame  2  is an engine  5 . Disposed above the engine  5  are a fuel tank  6  and the seat positioned rearward of the fuel tank  6 . Located forward of the fuel tank  6  are a handlebar  11  to be operated by a driver for controlling the front wheel  3  to steer the vehicle  1 , and a manually operable mechanism  10  provided on the handlebar  11  in accordance with the present invention. It is to be noted that the vehicle  1  is not be limited to the motorcycle and may be three-wheeled or four-wheeled straddle-type vehicle. 
     The manually operable mechanism  10  includes a first manual lever (a first manual operation member)  13  pivotably attached to the handlebar  11  through a first support shaft  12  such that the first manual lever is pivoted by the driver on the first support shaft  12 , and a second manual lever (a second manual operation member)  15  attached to the handlebar  11  through a second support shaft  14  in such a manner as to pivot on the second support shaft  14 . The second support shaft is disposed in the vicinity of the first support shaft  12 . 
     The handlebar  11  has a left grip  16 . A left switch box (an ancillary member)  17  is attached to a vicinity of the left grip  16 . A support member  20  for the manually operable mechanism  10  is attached to a vicinity of the left switch box  17 , and carries a bolt  18  and a U-shaped fitting  19 . The first manual lever  13  is attached to the support member  20  by the first support shaft  12 . Connected to the first manual lever  13  is a clutch wire or brake wire  21 . The second manual lever  15  is attached to the support member  20  by the second support shaft  14 . Connected to the second manual lever  15  is a parking brake wire  22 . 
     The first manual lever  13  includes an operational portion  23  to be operated or gripped by the driver. Since the first manual lever  13  is pivotable on the first support shaft  12 , the operational portion  23  is movable within a region A defined by phantom lines L 1 , L 2 . The second manual lever  15  shown in  FIG. 2  is in a position where a parking brake is released. When the second manual lever  15  is in such a position, the second manual lever  15  does not interfere with the region A. This means that the driver does not unintentionally operate the second manual lever  15  when he operates the first manual lever  13 . The driver can more freely operate the first manual lever  13  because he is not subject to constraints attributed to the second manual lever  15  in operating the first manual lever  13 . 
     As shown in  FIG. 3 , the first manual lever  13  includes a flange portion  36  having a hole  24  for allowing the first support shaft  12  to pass through the hole  24 . The first manual lever  13  further includes an output portion  26  formed integrally with and positioned oppositely from the operational portion  23 . The output portion  26  is preferably in the form of a projection but may take a variety of configurations. 
     The support member  20  for the manually operable mechanism  10  includes a body  27 , a lower bracket  29  attached to the body  27  by a screw  28 , and an upper bracket  32  attached to the body  27  by a screw  31 . A switch case  34  may be attached to a lower surface of the body  27  by a bolt  33 . 
     The body  27  of the support member  20  includes a recessed portion  35  for allowing the handlebar  11  to be fitted in the recessed portion  35 , and a pocket portion  37  for receiving the flange portion  36  of the first manual lever  13 . 
     The flange portion  36  of the first manual lever  13  is inserted within the pocket portion  37  of the body  27  and the first support shaft  12  is inserted through the pocket portion  37  and the flange portion  36 , with a torsion spring  38 , washers  39 , a stopper plate  41  and a nut  42  tightened onto a lower part of the first support shaft  12 . With this arrangement, the first manual lever  13  is pivotably attached to the body  27  of the support member  20 . 
     The second support shaft  14  includes a lower pin  14   a  and an upper pin  14   b . The second manual lever  15  is pivotably attached to the lower bracket  29  by the lower pin  14   a  and to the upper bracket  32  by the upper pin  14   b . The second manual lever  15  includes an operational portion  43  and an input portion  44  integral with the operational portion  43 . The input portion  44  is preferably in the form of a projection but may take a variety of configurations. 
     Attached to the upper bracket  32  is a hollow wire connecting member  45  covered with a resin cover  46 . Similarly, another hollow wire connecting member  45  is attached to the body  27  of the support member  20  and covered with a resin cover  46 . The body of the support member  20  has a front face covered with a cover  47 . 
     As shown in  FIG. 4 , the upper bracket  32  includes a curved surface  48  for guiding the parking brake wire  22 . The parking brake wire  22  is connected through an end ball  49  to a portion of the second manual lever  15 , which portion is located in the vicinity of the second support shaft  14 . The parking brake wire  22  shown in  FIG. 4  is in a position where a parking brake (not shown) is released. The parking brake wire  22  in such a position is not in contact with the curved surface  48  of the upper bracket  32 . The parking brake wire  22  shown in  FIG. 4  is urged by a spring (not shown) in such a direction (the right direction of  FIG. 4 ) as to release the parking brake. With the parking brake wire  22  thus urged, the second manual lever  15  is urged in such a manner as to pivot counterclockwise on the second support shaft  14 . 
     As shown in  FIG. 5 , a line  51  passing through the center of the second support shaft  14  and the center of the end ball  49  and a centerline (an axial line)  52  of the parking brake wire  22  define an angle θ therebetween. 
     When the second manual lever  15  is pivoted by a driver&#39;s hand in a clockwise direction on the second support shaft  14 , the end ball  49  is shifted upward to a position above the second support shaft  14 . With the end ball  49  positioned above the second support shaft  14 , the angle θ is “plus” (or θ&gt;0). When the angle θ is “plus”, the second manual lever  15  is urged by the parking brake wire  22  in such a manner as to pivot clockwise on the second support shaft  14 . During the clockwise pivotal movement of the second manual lever  15 , the parking brake wire  22  is guided by the curved surface  48  to thereby prevent the parking brake wire  22  from making tight contact with an exit of the hollow wire connecting member  45 . This can result in extended life of the parking brake wire  22 . 
     When the end ball  49  is positioned below the second support shaft  14 , the angle θ is “minus” (or θ&lt;0). That is, as the second manual lever  15  is pivoted counterclockwise from the position shown in  FIG. 5 , the end ball  49  is shifted downward to a position below the second support shaft  14  to thereby change the angle θ from “plus” through “zero” to “minus”. With the angle θ being “minus”, the second manual lever  15  is urged by the parking brake wire  22  in such a manner as to pivot counterclockwise on the second support shaft  14 . Therefore, whether the second manual lever  15  is urged by the parking brake wire  22  to pivot clockwise or counterclockwise depends upon whether the angle θ is “plus” or “minus”. 
     Discussion will be made as to how the manually operable mechanism  10  operates with reference to  FIG. 6  to  FIG. 8 . 
     Referring to  FIG. 6 , the second manual lever  15  is shown pulling the parking brake wire  22  with the parking brake held in an applied position. 
     As shown in  FIG. 7 , when the driver operates the operational portion  23  of the first manual lever  13  to cause the first manual lever  13  to pivot on the first support shaft  12  counterclockwise through an angle smaller than a predetermined angle, the output portion  26  of the first manual lever  13  comes into abutment on and presses the input portion  44  of the second manual lever  15 . By the output portion  26  pressing the input portion  44 , the second manual lever  15  is pivoted counterclockwise on the second support shaft  14  against an urging force of the parking brake wire  22 . 
     When the first manual lever  13  is further pivoted counterclockwise through the predetermined angle with the output portion  26  pressing the input portion  44 , the second manual lever  15  is further pivoted counterclockwise. At this point, the angle θ is changed from “plus” to “zero”. 
     As shown in  FIG. 8 , when the first manual lever  13  is further pivoted counterclockwise through an angle greater than the predetermined angle, the second manual lever  15  is further pivoted counterclockwise. At this point, the angle θ is changed from “zero” to “minus”. With the angle θ being “minus”, the input portion  44  moves away from the output portion  26  and the second manual lever  15  is pivoted counterclockwise toward a position (shown by a phantom line) by the urging force of the parking brake wire  22 , as indicated by an arrow. When the second manual lever  15  is pivoted counterclockwise to the position shown by the phantom line, the parking brake is released for allowing the vehicle  1  to travel. 
     As can be seen from the foregoing descriptions made with reference to  FIG. 6  to  FIG. 8 , when the first manual lever  13  is pivoted through an angle smaller than the predetermined angle, the output portion  26  of the first manual lever  13  presses the input portion  44  of the second manual lever  15  to thereby cause the second manual lever  15  to pivot in such a direction as to release the parking brake. When the first manual lever  13  is pivoted through an angle larger than the predetermined angle, the second manual lever  15  is pivoted by the urging force of the parking brake wire  22  in such a direction as to release the parking brake and the input portion  44  of the second manual lever  15  moves away from the output portion  26  of the first manual lever  13  so as to allow the second manual lever  15  to pivot independently of the first manual lever  13 . After the second manual lever  15  pivots independently of the first manual lever  13 , the first manual lever  13  is pivotable independently, which is easier-to-use for the driver. 
     Since the first manual lever  13  includes the output portion  26  for pressing the input portion  44  of the output portion  26 , it becomes possible to operate the second manual lever by operating the first manual lever, which provides an easy operation of releasing the parking brake. 
     When the first manual lever  13  is fully gripped by the driver&#39;s left hand to further pivot counterclockwise from the position shown in  FIG. 8  and the second manual lever  15  is pivoted by the driver&#39;s right hand clockwise from the position shown by the phantom line of  FIG. 8 , the output portion  26  of the first manual lever  13  serves as a stopper and limits movement of the input portion  44  of the second manual lever  15 . As a result, the second manual lever  15 , which has been pivoted clockwise, automatically pivots back to the position shown by the phantom line of  FIG. 8 . That is, when the first manual lever  13  is counterclockwise pivoted by the maximum amount or more than a predetermined amount, the second manual lever  15  can not be pivoted clockwise to a position where the parking brake is applied. This arrangement prevents the vehicle  1  from starting to travel with the parking brake applied. 
     The output portion  26  of the first manual lever  13  moves in a curve or arc of a first radius (first turning radius) R 1  during the pivotal movement of the first manual lever  13  on the first support shaft  12 . The first turning radius R 1  is defined as a distance between the first support shaft  12  and the output portion  26  of the first manual lever  13 . The input portion  44  of the second manual lever  14  moves in a curve or arc of a second radius (second turning radius) R 2  during the pivotal movement of the second manual lever  14  on the second support shaft  14 . The second turning radius R 2  is defined as a distance between the second support shaft  14  and the input portion  44 . The first turning radius R 1  is larger than the second turning radius R 2 . With the first turning radius R 1  larger than the second turning radius R 2 , a small amount of pivotal movement of the first manual lever  13  can causes a large amount of pivotal movement of the second manual lever  15 . Therefore, when the first manual lever  13  pivots counterclockwise through a small angle, the second manual lever  14  pivots through an angle which is so large that the input portion  44  moves away from the output portion  26  of the first manual lever  13  so as to allow the first manual lever  13  to pivot independently of the second manual lever  15 . That is, the first manual lever  13  can be operated independently of the second manual lever  14  in a short time after the first manual lever  13  is pivoted counterclockwise from the position shown in  FIG. 6 , which provides improved operability of the first manual lever  13 . 
       FIG. 9  shows a manually operable mechanism according to another embodiment of the present invention. The manually operable mechanism includes the second manual lever  15  having a distal end at a position located forward of a rear face of the left switch box  17  when the second manual lever  15  is pivoted to a position where the second manual lever  15  is directed perpendicularly to the handlebar  11 , as shown in  FIG. 9 . That is, the distal end of the second manual lever  15  directed perpendicularly to the handlebar  11  is forward offset by a distance “a” from the level of the rear face of the left switch box  17 . The distance “a” can be easily set by devising the configuration of the second manual lever  15  and the location of the second support shaft  14 . Even if an object is flown from a rear side of the handlebar  11  towards the second manual lever  15 , the object hits against the switch box  17  without interfering with the second manual lever  15 . 
     The second manual lever  17  may be provided on a right grip of the handlebar  11 . The vehicle  10  may be a three-wheeled or four-wheeled one employing the handlebar. 
     Although the first manual operation member and the second manual operation member have been described as being applied to the manual levers  13 ,  15 , the first and second manual operation members may be of dial-type. 
     INDUSTRIAL APPLICABILITY 
     The manually operable mechanism for a parking brake, according to the present invention is suitable for use in a motorcycle. 
     LEGEND 
       10 —manually operable mechanism;  11 —handlebar;  12 —first support shaft;  13 —first manual operation member;  14 —second support shaft second manual operation member;  20 —support member;  26 —output portion;  44 —input portion;  54 —front edge of first manual operation member;  55 —rear edge of handlebar