Abstract:
A vehicle is disclosed having an automatic idle adjustment system. The vehicle may also include an automatic shutdown system. A method for utilizing the automatic idle adjustment system and the shutdown system is also disclosed.

Description:
BACKGROUND 
       [0001]    1. Field of the Invention 
         [0002]    The present disclosure relates to a vehicle having a control system. More particularly, the present disclosure relates to a vehicle having an automatic idle adjustment system, and to a method for utilizing the same. 
         [0003]    2. Description of the Related Art 
         [0004]    A work vehicle, such as a loader, a bulldozer, an excavator, or a motor grader, may be operated to push, shear, carry, and/or spread soil and other material. When the work vehicle is not in use, the engine may be left running in an idle state. Even in this idle state, the vehicle consumes fuel and the engine is subjected to wear. 
       SUMMARY 
       [0005]    According to an embodiment of the present disclosure, a work vehicle is provided having a chassis, a ground engaging mechanism, an engine, a work tool, and a control system. The ground engaging mechanism is configured to support and propel the chassis. The engine is coupled to the ground engaging mechanism to power the ground engaging mechanism. The work tool is supported by the chassis to move material. The control system has an idle function configured to operate the engine in a first idle state for a first period of time, and to operate the engine in a second idle state after the first period of time expires. The engine operates at a lower speed in the second idle state than in the first idle state. 
         [0006]    According to another embodiment of the present disclosure, a work vehicle is provided having a chassis, a ground engaging mechanism, an engine, a work tool, an idle timer, and a shutdown timer. The ground engaging mechanism is configured to support and propel the chassis. The engine is coupled to the ground engaging mechanism to power the ground engaging mechanism. The work tool is supported by the chassis to move material. The engine operates in a first idle state, and the idle timer controls the duration of the first idle state. When the idle timer expires, the engine operates in a second idle state at a lower speed than in the first idle state. The shutdown timer controls the duration of the second idle state, and the engine shuts down when the shutdown timer expires. 
         [0007]    According to yet another embodiment of the present disclosure, a method is provided for automatically adjusting a speed of an engine of a work vehicle. The method includes the steps of providing a work vehicle having the engine and an idle timer, automatically starting the idle timer when the engine begins to operate in a first idle state, and automatically reducing the speed of the engine to operate in a second idle state when the idle timer expires. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The above-mentioned and other features of the present disclosure will become more apparent and the present disclosure itself will be better understood by reference to the following description of embodiments of the present disclosure taken in conjunction with the accompanying drawings, wherein: 
           [0009]      FIG. 1  is a side view of a work vehicle of the present disclosure; 
           [0010]      FIG. 2  is a schematic representation of a vehicle having a control system of the present disclosure; 
           [0011]      FIG. 3  is a graph of engine speed versus time showing the engine speed under control of an automatic idle adjustment and shutdown system of the present disclosure; 
           [0012]      FIG. 4  is a flow diagram depicting an automatic idle adjustment system of the present disclosure; 
           [0013]      FIG. 5  is a flow diagram similar to  FIG. 3  depicting an automatic idle adjustment system and an automatic shutdown system of the present disclosure; and 
           [0014]      FIG. 6  is a flow diagram similar to  FIG. 4  depicting an alternative automatic shutdown adjustment system of the present disclosure. 
       
    
    
       [0015]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate exemplary embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
       DETAILED DESCRIPTION 
       [0016]    Referring to  FIG. 1 , a work vehicle in the form of loader  10  is provided. Although the work vehicle is illustrated and described herein as loader  10 , the work vehicle may include any other type of work vehicle including a construction vehicle, such as a bulldozer, an excavator, or a motor grader, or an agricultural vehicle, such as a tractor, combine, or a harvester. Loader  10  includes articulated chassis  12  and ground engaging mechanism  14 . Ground engaging mechanism  14  may include any device capable of supporting and/or propelling chassis  12 . For example, as illustrated in  FIG. 1 , ground engaging mechanism  14  includes wheels. Ground engaging mechanism  14  may also include belts or steel tracks. Loader  10  also includes operator cab  16  supported by chassis  12  for an operator of loader  10 . Operator cab  16  includes a monitor (not shown) configured to communicate various messages to the user and receive inputs from the user. 
         [0017]    Referring to  FIGS. 1 and 2 , loader  10  further includes work tool  18  supported by chassis  12 . Work tool  18  may be forwardly mounted to chassis  12  and may include any device configured to move materials. For example, work tool  18  may include a bucket, as shown in  FIG. 1 , that scoops and dumps materials, such as dirt, sand, gravel, snow, salt, and other materials. Other work tools  18 , such as blades, pallet forks, bail lifts, augers, harvesters, tillers, mowers, and other work tools may also be provided to move materials. Loader  10  may also include hydraulic components  20  configured to operate work tool  18 . 
         [0018]    Referring still to  FIGS. 1 and 2 , loader  10  further includes engine  22 . Engine  22  is coupled to ground engaging mechanism  14  to power ground engaging mechanism  14 . Specifically, engine  22  may be coupled to a transmission (not shown), and the transmission may in turn be coupled to ground engaging mechanism  14  to power ground engaging mechanism  14 . Loader  10  also includes engine control unit  24  configured to control the operation of engine  22 . 
         [0019]    Referring still to  FIGS. 1 and 2 , loader  10  further includes system control unit  26 . System control unit  26  may be configured to communicate with various peripherals, such as throttle  28 , parking brake  30 , battery  32 , oil pump  34 , and/or ignition  36 . For example, system control unit  26  may receive signals from a throttle position sensor (not shown) indicating the position of throttle  28 , which controls the supply of fuel to engine  22 . System control unit  26  may also be configured to communicate with engine control unit  24  or with engine  22  directly. For example, system control unit  26  may be configured to monitor the speed of loader  10  across the ground. 
         [0020]    As shown in  FIG. 3 , the present disclosure provides an idle function, which reduces the wear on engine  22  and the amount of fuel consumed by loader  10 . The idle function is configured to operate engine  22  in first idle state  40  for first period of time  42  and to operate engine  22  in second idle state  44  for second period of time  46 . Second period of time  46  occurs after first period of time  42  expires. In both first idle state  40  and second idle state  44 , engine  22  is running, but ground engaging mechanism  14  is not driven. Engine  22  operates at a lower speed in second idle state  44  than in first idle state  40 . For example, the speed of engine  22  may drop by approximately 20% to 40% from first idle state  40  to second idle state  44 , and more specifically, the speed of engine  22  may drop from between approximately 900 and 950 rpm in first idle state  40  to between approximately 600 and 700 rpm in second idle state  44 . In addition to reducing the speed of engine  22  in second idle state  44 , hydraulic components  20  may be disabled and engine  22  may shift to operate along a different torque curve. 
         [0021]    Referring still to  FIG. 3 , the idle function is configured to be modified by a user. From the monitor in operator cab  16  ( FIG. 1 ), the user may disable the idle function altogether. Also from the monitor, the user may set an idle timer to control the duration of first period of time  42 . The duration of first period of time  42  may be chosen from various provided increments, such as 5, 15, and 30 minute increments. The duration of the idle timer may be set to abide by site-specific and/or state-specific idling requirements. 
         [0022]    Referring to  FIGS. 2 and 3 , to determine whether engine  22  is operating in first idle state  40  or second idle state  44 , system control unit  26  may monitor the behavior of engine  22  itself and/or various peripherals. More specifically, system control unit  26  may monitor the behavior of engine  22  directly or via engine control unit  24 , throttle  28 , parking brake  30 , battery  32 , and/or oil pump  34 . For example, system control unit  26  may determine that engine  22  is operating in first idle state  40  or second idle state  44  if one or more of the following conditions is satisfied: (1) engine  22  is operating at less than approximately 950 rpm; (2) engine  22  is operating at a load less than approximately 25%; (3) the position of throttle  28  is less than approximately 2.0%; (4) parking brake  30  is engaged; (5) ground speed is less than approximately 0.5 kph; (6) the voltage of battery  32  exceeds approximately 24V; and (7) the pressure at oil pump  34  is sufficient. System control unit  26  need not monitor the same peripherals to determine whether engine  22  is operating in first idle state  40  as it does to determine whether engine  22  is operating in second idle state  44 . For example, system control unit  26  may stop monitoring the load upon engine  22  when engine  22  begins to operate in second idle state  44 . 
         [0023]    An embodiment of the idle function is illustrated schematically as method  400  in  FIG. 4 . Beginning at block  402 , engine  22  is turned on. At block  404 , the idle timer is set to control the duration of first period of time  42 . For example, the idle timer may be set for 5, 15, or 30 minutes. At block  406 , system control unit  26  ensures that the idle function has not been disabled by the user. If the idle function has been disabled, method  400  ends at block  408 . If the idle function has not been disabled, method  400  continues to block  410 . At block  410 , system control unit  26  determines whether engine  22  is operating in first idle state  40  or in an active state. During normal operation of loader  10 , engine  22  will typically operate in the active state, not first idle state  40 , because engine  22  will be powering ground engaging mechanism  14  and/or hydraulic components  20 . Once system control unit  26  determines that engine  22  is operating in first idle state  40 , the idle timer is initiated at block  412  to start measuring first period of time  42 . Between blocks  414  and  416 , system control unit  26  ensures that engine  22  is operating in first idle state  40  until the idle timer expires at the end of first period of time  42 . If engine  22  begins to operate in the active state and ceases to operate in first idle state  40  before the idle timer expires, the idle timer is reset at block  404 . When the idle timer expires, the speed of engine  22  is reduced at block  422  to operate in second idle state  44 . At block  424 , system control unit  26  determines whether engine  22  is operating in second idle state  44 . If engine  22  begins to operate in the active state and ceases to operate in second idle state  44 , the idle timer is reset at block  404 . 
         [0024]    As shown in  FIGS. 2 and 3 , the present disclosure further provides a shutdown function, which reduces the wear on engine  22  and the amount of fuel consumed by loader  10 . The shutdown function is configured to shutdown engine  22  after second period of time  46 , in which engine  22  operates in second idle state  44 , expires. Engine  22  may be shutdown by turning off power to ignition  36  of loader  10 , which has the same effect as shutting down loader  10  with a key. For example, engine  22  may be shutdown by opening relay switch  50  between system control unit  26  and ignition  36 . 
         [0025]    Like the idle function, the shutdown function is configured to be modified by a user. From the monitor in operator cab  16  ( FIG. 1 ), the user may disable the shutdown function altogether. The user may choose to disable the idle function along with the shutdown function, or the user may choose to disable the shutdown function without disabling the idle function. Also from the monitor, the user may set a shutdown timer to control the duration of second period of time  46 . The duration of second period of time  46  may be chosen from various provided increments, such as 5, 15, and 30 minute increments. The duration of the shutdown timer may be set to abide by site-specific and/or state-specific idling requirements. 
         [0026]    An embodiment of the shutdown function is illustrated schematically as method  500  in  FIG. 5 . Overlapping steps in method  400  ( FIG. 4 ) and method  500  are labeled with the same last two digits. Beginning with block  502 , engine  22  is turned on. At block  504 , the idle timer is set to control the duration of first period of time  42 , and the shutdown timer is set to control the duration of second period of time  46 . For example, the idle timer and the shutdown timer may each be set for 5, 15, or 30 minutes. Blocks corresponding to blocks  406 - 412  of method  400  have been omitted from  FIG. 5  because they are similar to blocks  406 - 412  of method  400 . Between blocks  514  and  516 , system control unit  26  ensures that engine  22  is operating in first idle state  40  until the idle timer expires at the end of first period of time  42 . If engine  22  begins to operate in the active state and ceases to operate in first idle state  40  before the idle timer expires, the idle timer is reset at block  504 . When the idle timer expires, system control unit  26  ensures at block  518  that shutdown function  38  has not been disabled by the user. If the idle function has not been disabled, the shutdown timer is initiated at block  520  to start measuring second period of time  46 , and then the speed of engine  22  is reduced at block  522  to operate in second idle state  44 . If the idle function has been disabled, the shutdown timer is not initiated at block  520  before reducing the speed of engine  22  at block  522 . Between blocks  524  and  530 , system control unit  26  ensures that engine  22  is operating in second idle state  44  until the shutdown timer expires at the end of second period of time  46 . If engine  22  begins to operate in the active state and ceases to operate in second idle state  44  before the shutdown timer expires, the idle timer and the shutdown timer are reset at block  504 . If the shutdown timer expires, engine  22  is shutdown at block  532 . 
         [0027]    Another embodiment of the shutdown function is illustrated schematically as method  600  in  FIG. 6 . Overlapping steps in method  400  ( FIG. 4 ), method  500  ( FIG. 5 ), and method  600  are labeled with the same last two digits. Like method  500 , between blocks  624  and  630 , system control unit  26  ensures that engine  22  is operating in second idle state  44  until the shutdown timer expires at the end of second period of time  46 . Unlike method  500 , method  600  includes blocks  626  and  628  between blocks  624  and  630 . When the shutdown timer is nearing expiration, an alarm is operated at block  628 . For example, when the shutdown timer is within 30 seconds of expiration, an audible alarm may sound and a message may appear on the monitor in operator cab  16  ( FIG. 1 ). The audible alarm may include a series of clicks that becomes more frequent as the shutdown timer approaches expiration. Similarly, the audible alarm may increase in pitch or volume as the shutdown timer approaches expiration. Like method  500 , if engine  22  begins to operate in an active state and ceases to operate in second idle state  44  before the shutdown timer expires, the idle timer and the shutdown timer are reset at block  604 . If the shutdown timer expires, engine  22  is shutdown at block  632 . 
         [0028]    While this invention has been described as having preferred designs, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.