Abstract:
A method is provided for alternately triggering driving states of a utility vehicle. The method includes providing a control element and a transmission selectively engageable in a forward driving state (F) for forward travel of the utility vehicle, a reverse driving state (R) for reverse travel, and a standstill driving state (S) for a stationary output of the transmission without disconnection of the drivetrain in the utility vehicle. The method further includes operating the transmission in a current driving state, operably selecting a target driving state while operating in the current driving state, and controllably triggering the transmission to the standstill driving state before shifting the transmission to the target driving state.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of German Application Ser. No. 102016203763.3, filed on Mar. 8, 2016, the disclosure of which is hereby expressly incorporated by reference in its entirety. 
       FIELD OF THE DISCLOSURE 
       [0002]    The present disclosure relates to a method and an arrangement for controlling driving states of a utility vehicle. 
       BACKGROUND 
       [0003]    Utility vehicles are used, among other things, for performing certain work functions. These include, for example, loading or transport work for the performance of which the utility vehicle has suitable implements. For an agricultural utility vehicle, these implements include a loading shovel, a manure fork or other implements. Appropriate actuating elements and instruments for actuating these implements are usually provided in the driver&#39;s cab of the utility vehicle. In addition, the driver must often change the driving direction between “forward” and “reverse” while performing such work functions. For this purpose, at least one corresponding actuating element is provided for the driver. 
       SUMMARY 
       [0004]    In one embodiment of the present disclosure, a method is provided for alternate triggering of driving states “forward” and “reverse” by means of a control element. “forward” in this case means forward travel driven by a transmission of the utility vehicle, and “reverse” means reverse travel driven by the transmission of the utility vehicle. A target driving state (“reverse” or “forward”) an be activated from a current driving state (“forward” or “reverse”) by means of the control element. 
         [0005]    A “standstill” driving state is also provided which corresponds to a stationary output of the vehicle transmission without disconnecting the drivetrain with a clutch. This driving state is also referred to as active standstill and is possible particularly for tractors with a continuously variable transmission. Such continuously variable transmissions also allow startup from standstill without a startup clutch. For transmissions that do not have active standstill, the neutral position of the transmission or the disengagement of the drive clutch constitutes the driving state “standstill.” 
         [0006]    Irrespective of this, the “standstill” driving state is often desired or necessary for an intended change of drive direction (“forward” to “reverse” or “reverse” to “forward”) as a temporary operating state or intermediate state in order to be able to support the utility vehicle in terms of traction or safety. The “standstill” driving state terminates the drive movement of the drive axle(s) of the utility vehicle during a current driving state “forward” or “reverse.” 
         [0007]    At least one additional driving state can be provided. 
         [0008]    Controlling the utility vehicle, in particular a tractor or some other agricultural vehicle, during operation thereof (e.g. loading work) is now simplified in a user-friendly manner by triggering the control element in case of an intended change of the current driving state in such a manner that the “standstill” driving state is automatically initially activated before activating the target driving state. 
         [0009]    The term “triggering” a driving state (e.g. target driving state or “standstill”) is to be understood to mean that this driving state is achieved or activated by actuating the control element. 
         [0010]    This means that in an intended change from a current driving state “forward” to a target driving state “reverse,” or from a current driving state “reverse” to a target driving state “forward,” the “standstill” driving state is triggered first. Only after that can the actually intended driving state be achieved or activated. In this way, an intuitive and simple control of the utility vehicle by the vehicle driver or user is enabled, by avoiding conventionally required additional and cumbersome control processes with different control routes or additional operating elements to achieve the “standstill” driving state when changing direction from “forward” to “reverse” and vice versa. Advantageously, the control function for the “standstill” driving state and also the control movement necessary for this can be integrated into a control element provided for changing the actual travel direction and into the control movements thereof. Consequently the user can easily control an intended change of travel direction and can trigger the “standstill” driving state because the triggering of the “standstill” driving state is integrated into the control process for the change of travel direction. 
         [0011]    Since the “standstill” driving state is automatically triggered during an intended triggering of a target driving state, it is guaranteed that the “standstill” driving state is first activated before a change of travel direction, without an additional control effort by the user or the vehicle driver. 
         [0012]    This triggering principle contributes to being able to reduce the number of different operating functions or operating elements for controlling the utility vehicle. Therefore the corresponding arrangement with the control element and optionally additional operating elements can be provided in a correspondingly more space-saving and less complex manner. 
         [0013]    The target driving state is triggered by the control element by means of a change-control movement, wherein the “standstill” driving state is automatically achieved before or during such a change-control movement. Thereby the triggering of the temporary driving state “standstill” is integrated in a user-friendly and intuitive manner into the process of the change-control movement. 
         [0014]    In an advantageous embodiment, the control element is releasably locked during a current driving state, and this locking must be released before performing the change-control movement. This reliably avoids unintentional erroneous operation of the control element. The release of this locking can preferably activate the temporary driving state “standstill” in an additional function. The “standstill” driving state is thus automatically triggered without additional operating effort before an intended change-control movement. 
         [0015]    For example, a pushbutton can be actuated on the control element to release the locking. Actuating this pushbutton can then simultaneously effect an activation of the “standstill” driving state. This multiple function of the pushbutton supports a simply designed structure of the control element. 
         [0016]    Alternatively, a defined segment or component of the change-control movement of the control element can be considered a basic control movement in such a manner that the “standstill” driving state is triggered or activated by performing the basic control movement. In this way, different movement processes of the control element for triggering the target driving state on the one hand and the “standstill” driving state on the other can be avoided in a simple manner. 
         [0017]    A user-friendly triggering by means of the control element is further supported in that the change in control movement of the control element for activating a target driving state includes a repeated performance of the basic control movement, and in particular consists only of a repeated performance of the basic control movement. For example, the “standstill” driving state is triggered by a first performance of the basic control movement, while a subsequent performance of the same basic control movement triggers the target driving state. Thereby the control movements for triggering the different driving states are particularly simple and user-friendly. 
         [0018]    An additional embodiment supports a reliable actuation of the control element by providing at least one catch position for detachable engagement of the control element during performance of the change-control movement or basic control movement. By means of the catch position(s), an unambiguous position of the control element is always achieved during the various triggering processes in a technically simple manner. 
         [0019]    In particular, the transfer of the control element into a catch position can correspond to the triggering of a driving state (in particular, “forward,” “reverse,” or “standstill”), whereby the triggering of the various driving states can be even more intuitive for the user. 
         [0020]    It is also provided that the control element is in a defined rest position during a current driving state. In this way, the current status of the control element can be unambiguously recognized by the user in a simple manner. 
         [0021]    In particular, the control element is automatically brought back into its rest position (by means of a suitable mechanism) after triggering the “standstill” driving state or a target driving state, which simplifies the handling of the control element for the user or the vehicle driver. 
         [0022]    The individual control movements of the control element can be performed particularly simply and intuitively by forming the control element preferably as a pivoting control lever. 
         [0023]    Alternatively, the control element can be designed as a rotatable or turnable roller, whereby the control element can be arranged in a particularly space-saving manner and can be comfortably operated by the user with one finger. 
         [0024]    An arrangement in the driver&#39;s cab can include the control element for changing the driving direction. This arrangement can contain additional operating elements for controlling or performing various functions of the utility vehicle (e.g. a tractor or some other agricultural vehicle). An actuating instrument for controlling a work function (e.g. transporting material by means of a loading shovel) of the utility vehicle can also be provided as a component of the arrangement. In order to make the necessary driving direction change during such work functions more comfortable for the user or vehicle driver, the control element is arranged on the above-mentioned actuating instrument. In this way, the user can control both work functions and a desired change of driving direction with the same hand on a single actuating instrument. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    The above-mentioned aspects of the present disclosure and the manner of obtaining them will become more apparent and the disclosure itself will be better understood by reference to the following description of the embodiments of the disclosure, taken in conjunction with the accompanying drawings, wherein: 
           [0026]      FIG. 1  is a schematic side view of handling a control element in a first embodiment, 
           [0027]      FIG. 2  is a schematic side view of handling a control element in a second embodiment, 
           [0028]      FIG. 3  is a schematic side view of handling a control element in a third embodiment, 
           [0029]      FIG. 4  is a perspective view of an additional embodiment of the control element, and 
           [0030]      FIG. 5  is a perspective representation of an actuating instrument having an integrated control element. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    In a first embodiment, the method and the arrangement with a control element  10  for controlling a drive direction change of a utility vehicle will be described in detail with reference to  FIGS. 1-5 . At least the following driving states may be possible for the utility vehicle:
       “Forward” (with reference sign “F”) for forward travel driven by the transmission of the utility vehicle;   “Reverse” (with reference sign “R”) for reverse travel driven by the transmission of the utility vehicle; and   “Standstill” (with reference sign “S”) for stationary output of the transmission without disconnection of the drivetrain in the utility vehicle. For transmissions that do not have an active standstill, the neutral position of the transmission or the disengagement of the drive clutch can take the place of such an active standstill.       
 
         [0035]      FIG. 1  shows a first embodiment for the handling and mode of operation of a lever-like control element  10 , which is mounted pivotably about a schematically shown pivot bearing  12 . The pivot bearing  12  is coupled, in a manner not shown here, to a control mechanism that activates a desired new driving state (target driving state) depending on the pivot position of the control element  10 . During a current driving state F, R, or S, the control element  10  is in a center resting position  14 . In this resting position  14 , the control element  10  is releasably locked, for example, by means of a locking pin  13  that engages with the pivot bearing  12  under a preload from a spring force and that can be pressed out of the pivot bearing  12  by actuating the pushbutton  16 . 
         [0036]    If the utility vehicle is currently driving in reverse R and a change of driving direction to F is to be performed, the user first releases the locking of the control element  10 . A pushbutton  16  is pressed in the direction of the pivot bearing  12  for this purpose. This actuation of the pushbutton  16  automatically activates the driving state S. In this manner, the reverse driving of the utility vehicle is first terminated in a defined and automatic manner before the actual change of driving direction. Only after the locking is released, i.e., only after activation of the driving state S, can the control element  10  carry out a change-control movement  18  by being pivoted in the direction of a target position  20 . For a current driving state R, this target position  20  corresponds to the target driving state F. 
         [0037]    In principle, the same actuation of the control element  10  is provided if the vehicle is to change to the target driving state R while in a current driving state F. The control element  10  carries out a change-control movement  22  in the opposite direction of the change-control movement  18 , in the direction of a target position  21  which corresponds to the target driving state R. After triggering the target driving state F or R, the control element  10  is automatically returned to its rest position  14  by means of a suitable mechanism. 
         [0038]    The control element  10  according to  FIG. 2  is again in the resting position during a current driving state F, R, or S. The control element  10  can be protected against unintended movements out of the rest position by a spring force or releasable locking or the like. The control element  10  is again pivoted in order to carry out a change-control movement  18  or  22  for a driving direction change. Here, however, the change-control movement  18  or  22  is composed of two successively performed basic control movements  24  or  26 . The basic control movement  24  or  26  is thus repeated once in order to trigger the target driving state. After carrying out the basic control movement  24  or  26  or the change-control movement  18  or  22 , i.e., after activation of the driving state S or the driving state F or R—the control element  10  is automatically returned by means of a suitable mechanism to its resting position  14 . In this control scheme, the user must also necessarily or automatically first activate the driving state S before the desired target driving state F or R is triggered. 
         [0039]    The control element  10  according to  FIG. 3  differs from the variant according to  FIG. 2  particularly by a different design of the change-control movement  18  or  22 . The basic control movement  24  or  26  for triggering the temporary driving state S in this case forms a first portion of the overall change-control movement  18  or  22 . After the entire change-control movement  18  or  22  has been performed, the desired target driving state F or R is activated. A user-friendly handling of the control element  10  is supported in that, starting from the resting position  14 , the states S, F, and R to be triggered each correspond to a specific catch position  28 ,  30 ,  32 , or  34 . In these catch positions  28 ,  30 ,  32 ,  34 , the control element  10  is releasably engaged so that the triggered driving state is unambiguously signaled to the user. This releasable engagement is achieved, for example, by a catch element  36  that, under a preload from a spring force, presses against a control track  38  of the pivot bearing  12  or engages with individual recesses  40 ,  42  of this control track  38 . 
         [0040]    In the variant according to  FIG. 3 , the control element  10  is automatically returned by a suitable mechanism to its resting position  14  at least after performing the change-control movement  18  or  22 , i.e., after activating the target driving state F or R. 
         [0041]    As illustrated on the basis of  FIGS. 1-3 , the control element  10  can be constructed as a pivoting control lever. Alternatively, the control element  10  can be constructed according to  FIG. 4  as a turnable or rotatable control roller, which is suitable for operation by means of a finger or thumb of the user. In principle, the same control schemes or control movements as those shown with  FIGS. 1-3  can be implemented with this control unit. 
         [0042]      FIG. 5  shows an actuating instrument  44  (e.g. a joystick) that is equipped with corresponding control functions for controlling various work functions of a utility vehicle, e.g., a tractor or some other agricultural vehicle. The control element  10  is integrated into this actuating instrument by being arranged on a side surface of the actuating instrument  44 . Varying from this, an arrangement on a top, front, rear or lower surface of the actuating instrument  44  can also be provided. The user or driver of the utility vehicle can therefore control both work functions and desired driving direction changes in a user-friendly manner with one hand and a single actuating instrument. 
         [0043]    While embodiments incorporating the principles of the present disclosure have been described hereinabove, the present disclosure is not limited to the described embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of the disclosure 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 disclosure pertains and which fall within the limits of the appended claims.