Abstract:
The pedal lever has a boss portion which acts as a center of rotation, and a first lever and a second lever which extend from the boss portion in two directions, wherein the reverse lever is coupled with an extending extreme end portion of the first lever, and the accelerator pedal is coupled with an extending extreme end portion of the second lever, and an operation unit is arranged on a side opposite to the extending extreme end portion across the boss portion, the operation unit operating the accelerator switch.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This is a Continuation Application of PCT Application No. PCT/JP2006/305587, filed Mar. 20, 2006, which was published under PCT Article 21(2) in Japanese.  
         [0002]     This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2005-083574, filed Mar. 23, 2005, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0003]     1. Field of the Invention  
         [0004]     The present invention relates to an accelerator pedal operation device for transmitting an amount of depression of an accelerator pedal to an accelerator stroke sensor.  
         [0005]     2. Description of the Related Art  
         [0006]     Ordinarily, in vehicles and the like on which an electronically controlled engine is mounted, an amount of depression of an accelerator pedal is transmitted to an accelerator stroke sensor, an electronic signal corresponding to the amount of depression of the accelerator pedal is generated, and an engine is controlled in response to the electronic signal.  
         [0007]     Conventionally, a cable has been used as means for transmitting the amount of depression of the accelerator pedal to the accelerator stroke sensor.  
         [0008]     Ordinarily, the accelerator pedal is installed in a front narrow portion on a floor of a driver&#39;s cabin. For this reason, when the cable is employed as the means, a job for wiring and connecting the cable is troublesome and an efficiency of the job is deteriorated. Further, since there is a possibility of breakage and the like in the transmission means composed of the cable, its reliability is low.  
         [0009]     Accordingly, recently, a system for transmitting an amount of depression of an accelerator pedal to an accelerator stroke sensor through a link mechanism is employed as found in, for example, Jpn. Pat. Appln. KOKAI Publication No. 7-150987.  
       BRIEF SUMMARY OF THE INVENTION  
       [0010]     Incidentally, an accelerator pedal is provided with an accelerator switch for detecting whether or not the accelerator pedal is depressed. Conventionally, since the accelerator switch has been arranged on a floor of a driver&#39;s cabin adjacent to the accelerator pedal, not only an accelerator switch assembly job is troublesome but also the accelerator switch may stand in the way of operation of the accelerator pedal.  
         [0011]     An object of the present invention, which has been made in view of the above point, is to provide an accelerator pedal operation device in which an accelerator switch can be easily and effectively installed in a narrow space of a driver&#39;s cabin together with a link mechanism such that the accelerator switch does not disturb operation of the accelerator pedal at all.  
         [0012]     In an accelerator pedal operation device according to an aspect of the present invention having a pedal lever which turns in response to depression of an accelerator pedal, a link mechanism having a reverse lever, which turns in association with the pedal lever, and is arranged as a unit structure, an accelerator stroke sensor which detects an amount of rotation of the reverse lever of the link mechanism and controls an amount of fuel injected into an engine, and an accelerator switch assembled to the link mechanism integrally therewith, the accelerator switch detecting whether or not the accelerator pedal is depressed in association with the pedal lever.  
         [0013]     A preferred aspect of the present invention wherein the pedal lever having a boss portion which acts as a center of rotation, and a first lever and a second lever which extend from the boss portion in two directions, wherein the reverse lever is coupled with an extending extreme end portion of the first lever, and the accelerator pedal is coupled with an extending extreme end portion of the second lever, and an operation unit is arranged on a side opposite to the extending extreme end portion across the boss portion, the operation unit operating the accelerator switch.  
         [0014]     Further, a preferred aspect of the present invention wherein the accelerator switch is arranged so as to move with respect to the link mechanism so that a position of the accelerator switch can be adjusted with respect to the operation unit of the pedal lever. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0015]      FIG. 1  is a side elevational view showing an accelerator pedal device according to an embodiment of the present invention.  
         [0016]      FIG. 2  is a side elevational view showing a state in which an accelerator pedal of the accelerator pedal device is depressed.  
         [0017]      FIG. 3  is a perspective view showing a link mechanism of the accelerator pedal device.  
         [0018]      FIG. 4  is a side elevational view showing an accelerator switch of the accelerator pedal device. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]     An embodiment of the present invention will be described with reference to the drawings.  
         [0020]     As shown in  FIGS. 1 and 2 , a pedal holder  3  having an accelerator pedal  2  is installed on a floor of a driver&#39;s cabin  1  of a vehicle. An end of the accelerator pedal  2  on one end side is upward and downward turnably attached to the pedal holder  3  through a shaft  4 . The pedal holder  3  is provided with a stopper  5  for adjusting a maximum stroke width of depression of the accelerator pedal  2 .  
         [0021]     Note that  FIG. 1  shows a state before the accelerator pedal  2  is depressed, and  FIG. 2  shows a state when the accelerator pedal  2  is depressed up to the maximum stroke width.  
         [0022]     An accelerator stroke sensor  7  and a link mechanism  8  associating with the accelerator stroke sensor  7  are arranged to a front upper portion of the driver&#39;s cabin  1 . As shown in  FIGS. 1, 2 , and  3 , the link mechanism  8  has a base  10 , and a reverse lever  11  and a pedal lever  12  are turnably attached to the base  10  through shafts  13 ,  14 , respectively, thereby an integral unit structure is constructed.  
         [0023]     The reverse lever  11  is bent to a C-shape, the shaft  13  is inserted into the bent portion, and the reverse lever  11  turns about the shaft  13 . The pedal lever  12  has a boss portion  15 , the shaft  14  is inserted into the boss portion  15 , and the boss portion  15  turns about the shaft  14 .  
         [0024]     A first lever  16  extends in one direction and a second lever  17  extends in the other direction from the boss portion  15  integrally therewith, respectively. Further, a projecting-piece-like operation unit  18  is arranged to a side opposite to the second lever  17  with respect to the boss portion  15  integrally with the second lever  17  so as to extend in a direction opposite to the second lever  17 .  
         [0025]     A spring  20  is assembled to the boss portion  15 , and the pedal lever  12  is elastically urged by the spring  20  counterclockwise in the figure in its entirety.  
         [0026]     The end of the first lever  16  of the pedal lever  12  on an extreme end side is coupled with an end of the reverse lever  11  on one end side through a pin  22 . The pin  22  is attached to the end of the first lever  16  and loosely fitted to a slot (not shown) formed to the end of the reverse lever  11 . Consequently, the reverse lever  11  is turned about the shaft  13  in response to the turn of the pedal lever  12 .  
         [0027]     The second lever  17  of the pedal lever  12  extends into the driver&#39;s cabin  1 , the end of the accelerator pedal  2  on a free end side is placed on and fitted to the end of the second lever  17  on an extreme end side, and the pedal lever  12  is turned in response to depression of the accelerator pedal  2 .  
         [0028]     The accelerator stroke sensor  7  has a swingable operation lever  25 , and an end of the operation lever  25  is turnably coupled with an end of the reverse lever  11  on the other side through a pin  26 . The pin  26  is attached to the end of the operation lever  25  and loosely fitted to a slot  24  formed to an end of the reverse lever and shown in  FIG. 3 . Consequently, the operation lever  25  is swung in response to the turn of the reverse lever  11 .  
         [0029]     A bracket  27  is attached to the base  10  of the link mechanism  8 , and an accelerator switch  28  is attached to the bracket  27  so as to confront with the operation unit  18  of the pedal lever  12 .  
         [0030]     As shown in  FIG. 4 , the accelerator switch  28  has a shaft portion  30  extending from an upper portion of a main body  29  upward together with it, and the shaft  30  is inserted into a through hole  27   a  formed to an end of the bracket  27  from under it.  
         [0031]     A screw  30   a  is formed around the outer peripheral surface of the shaft portion  30 , a pair of nuts  31   a ,  31   b  are screwed on the screw  30   a , these nuts  31   a ,  31   b  are arranged on and under the bracket  27  so as to clamp it, and the accelerator switch  28  is tightly attached to the bracket  27  by tightening these nuts  31   a ,  31   b  and supported, so that the height of it is set to a predetermined level. The level of the height can be changed by loosening the nuts  31   a  and  31   b.    
         [0032]     The accelerator switch  28  has a switch button  33  at an upper end portion of the shaft portion  30 , and the switch button  33  is urged so as to elastically project upward and arranged so as to confront with the operation unit  18  of the pedal lever  12 .  
         [0033]     Note that the accelerator stroke sensor  7  and the accelerator switch  28  are electrically connected to an engine control unit (not shown) for controlling an amount of fuel injected into an engine.  
         [0034]     In a free state in which the accelerator pedal  2  is not depressed, the operation unit  18  comes into contact with the switch button  33  of the accelerator switch  28  by elastic force of the spring  20  assembled to the boss portion  15  of the pedal lever  12 , thereby the switch button  33  is pushed downward with predetermined pressure and the accelerator switch  28  is kept in a turned on state.  
         [0035]     When the accelerator pedal  2  is depressed downward from the engine idling state, the pedal lever  12  is turned clockwise in the figure about the shaft  14  against the spring  20 . Thereby, the operation unit  18  of the pedal lever  12  is released from the switch button  33  of the accelerator switch  28 . The switch button  33  is switched from the turn on state to a turn off state, thereby depression of the accelerator pedal  2  is detected, and a signal of depression is sent to the engine control unit.  
         [0036]     Further, the reverse lever  11  is turned counterclockwise about shaft  13  in association with the clockwise turning operation of the pedal lever  12  and the operation lever  25  of the accelerator stroke sensor  7  is swung by the turning operation, thereby an amount of turn of the reverse lever  11  is detected, and a signal of detection is sent to the engine control unit.  
         [0037]     Since the signal from the accelerator switch  28  and the signal from the accelerator stroke sensor  7  are sent to the engine control unit as described above, an amount of fuel injected into the engine is controlled through the engine control unit.  
         [0038]     An amount of depression of the accelerator pedal  2  is proportional to an amount of swing of the operation lever  25  of the accelerator stroke sensor  7  and the operation lever  25  is swung at a stroke according to an amount of depression of the accelerator pedal  2 , thereby the amount of fuel injected into the engine is controlled to a proper amount.  
         [0039]     Incidentally, when the stroke sensor  7  does not act normally due to a fault and a predetermined signal is not output regardless of whether the accelerator pedal  2  is depressed and a signal of the accelerator switch  28  is output to the engine control unit therefrom, the amount of fuel injected into the engine is adjusted to such a degree as to cause the vehicle to travel at a very slow speed under the control of the engine control unit.  
         [0040]     As described above, the accelerator switch  28  is a member for detecting whether or not the accelerator pedal  2  carries out a depression operation. However, in the embodiment, the accelerator switch  28  is assembled to the link mechanism  8  integrally with it and arranged to the front portion of the driver&#39;s cabin  1  spaced apart from the accelerator pedal  2 , and therefore, it does not disturb operation of the accelerator pedal  2  at all.  
         [0041]     Further, the accelerator switch  28  is assembled to the link mechanism  8 , which transmits the stroke of the accelerator pedal  2  to the accelerator stroke sensor  7 , integrally with it and arranged as a unit. Accordingly, it is not necessary to carry out a troublesome job for attaching the accelerator switch  28  to a narrow space in the driver&#39;s cabin  1  as a single unit, and it can be easily and effectively installed in the driver&#39;s cabin  1  together with the link mechanism  8 .  
         [0042]     The accelerator switch  28  must be arranged at a position having a predetermined proper height based on the pedal lever  12  as a standard. That is, it is important to adjust the operation unit  18  of the pedal lever  12  such that it properly comes into contact with the switch button  33  of the accelerator switch  28  in idling as well as being securely released therefrom when the accelerator pedal  2  begins to be depressed. However, the operation unit  18  can be easily adjusted by moving the shaft portion  30  up and down by loosening the nuts  31   a  and  31   b.    
         [0043]     Note that the present invention is by no means restricted to the above embodiment and can be embodied by appropriately modifying the components of the present invention such as the pedal lever and the reverse lever within a range that does not depart from the gist of the present invention.  
         [0044]     According to the present invention, the accelerator switch can be easily and effectively installed in the narrow space of the driver&#39;s cabin together with the link mechanism , and also does not disturb operation of the accelerator pedal at all.