Abstract:
A header is removably attached to lift arms of an agricultural harvester and by a tilt cylinder pivotable about an axis A between an elevated installation position and a lower operational position. A perch assembly including a perch is positioned adjacent axis A to remotely pivot the tilt cylinder between the installation and operating positions and a downwardly facing hook shaped latching device is mounted on the tilt cylinder to engage and attach to a mounting pin on the header.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to agricultural harvesters, and more specifically to apparatus for removably attaching a header to such harvesters. 
         [0003]    2. Description of the Related Art 
         [0004]    In the quest for ever increasing operational efficiency, agricultural harvesters incorporate easily removable headers to provide flexibility in the type of crop to be harvested. Along with the flexibility of changing out the header, it has been a goal make the installation and removal as quick as possible but at the same time promoting operator efficiency and comfort. 
         [0005]    Existing header assemblies are usually supported by a pair of lower lift arms pivotally secured to the main body of the agricultural harvester and a third arm between and above the lower lift arms. The lift arms are pivotable through appropriate actuators to change the height of the header relative to the ground to facilitate harvesting of varied crops. The connection between the lift arms and the header is accomplished by upwardly facing U-shaped recesses on the ends of the lift arm which mate with corresponding mounting pins on the header. In order for the mounting pins, and thus the header, to be safely secured to the agricultural harvester, a locking bar mounted on the lift arms is slidable between an unlocked position permitting installation and removal of the mounting pins and a locked position where the pins are captured in the U-shaped recesses. 
         [0006]    The third arm connecting the header to the agricultural harvester is connected to an actuator frequently referred to as a tilt cylinder having a hydraulic cylinder secured to the agricultural harvester and an extensible rod connectable by a pin to the header. The overall length of the tilt cylinder is varied to change the attitude of the header for the appropriate harvesting conditions. When the header is being coupled to the agricultural harvester, it is currently a multi-step process in which the operator manually positions the tilt cylinder in an elevated position out of the way of the lift arms. The operator then drives the agricultural harvester to a point where the lift arms may be attached to the lower portion of the header. At that point a third step is required for the operator to manually lower the tilt arm so that an appropriate fitting, such as a Heim joint, lines up to connect with the appropriate element on the header by means of a removable pin. Subsequently, the operator must then re-enter the operator cab to proceed with the harvesting function. The requirement for the multi steps of exiting and entering the cab take away from the efficiency of the overall harvesting process which can result in reduced economic gain. 
         [0007]    Accordingly, what is needed in the art is an apparatus for remotely and positively connecting the tilt cylinder of an agricultural harvester to a header. 
       SUMMARY OF THE INVENTION 
       [0008]    In one aspect of the present invention, the above objects are achieved by a mechanism that permits remote attachment of the tilt cylinder. 
         [0009]    In one form, the invention is an apparatus for remotely attaching a tilt cylinder to the connecting pin of an agricultural header with the tilt cylinder having a hydraulic cylinder pivotally mounted on an agricultural harvester about an axis A and a rod extendable from the cylinder for connection to the connecting pin. The apparatus includes a perch assembly positioned adjacent the pivotal axis A and connectable with the tilt cylinder to pivot the tilt cylinder in an arc between an elevated installation position and a lower operational position. A downward facing hook is provided on the tilt cylinder for engaging the pin on the agricultural header when the perch assembly pivots the tilt cylinder between the elevated installation position and the lower operational position. 
         [0010]    In another form, the invention is an agricultural harvester having a frame, ground drive wheels connected to the frame for ground movement, a header removably attached to the frame for harvesting agricultural crops with the header having at least one mounting pin. A tilt cylinder is pivotally mounted to the frame about an axis A with the tilt cylinder having hydraulic cylinder and an extendable rod. A perch assembly is positioned adjacent the pivotal axis A and is connectable to the tilt cylinder to pivot the tilt cylinder in an arc between an elevated installation position and a lower operational position. A downward facing hook on the tilt cylinder is engagable with the pin on the agricultural header when the perch assembly pivots the tilt cylinder between the elevated installation position and the lower operational position. 
         [0011]    One advantage of the present invention is that the tilt cylinder of an agricultural harvester may be remotely manipulated between an installation and an operational position. 
         [0012]    Another advantage is that an operator does not have to leave an operator cab when attaching the tilt cylinder to the header of an agricultural harvester. 
         [0013]    Still another advantage of the present invention is the positive placement of the tilt cylinder relative to the header during the installation operation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0015]      FIG. 1  is an elevational view of a portion of an agricultural harvester and a header with which the present invention may be used; 
           [0016]      FIG. 2  is a perspective view of a portion of the agricultural harvester of  FIG. 1  showing the interconnection between the header and the agricultural harvester; 
           [0017]      FIG. 3  shows a perch assembly embodying the present invention in place on the agricultural harvester of  FIGS. 1 and 2 ; 
           [0018]      FIG. 4  is an expanded partial view of the perch assembly of  FIG. 3 ; 
           [0019]      FIG. 5  is a perspective detailed view of a portion of the perch assembly of  FIGS. 3 and 4 ; and 
           [0020]      FIG. 6  is a schematic view of a hydraulic control system used with the present invention. 
       
    
    
       [0021]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates embodiment of the invention and such exemplification is not to be construed as limiting the scope of the invention in any manner. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    Referring now to the drawings, and more particularly to  FIG. 1 , there is shown an agricultural harvester  10  incorporating a frame  12  and an operator cab  14 . Ground drive wheels  16  are provided to enable the harvester to traverse a field. A header assembly  18  is removably attached to the agricultural harvester  10  in a manner to be described below. To enable a clear understanding of the present invention, other portions of the agricultural harvester  10  are not shown such as a power unit, drive train and crop processing unit. It is to be understood by those skilled in the art that these may be implemented to complete the function of the agricultural harvester  10  in traversing a field, severing crops and processing them for the grain material. 
         [0023]    The header  18  is supported at its bottom edge by lift arms  20  secured to the forward portion of agricultural harvester  10 . The header  18  has a frame  22  and a central arm  24  which connects to an actuator  26  known as a tilt cylinder shown as a dashed line extending to frame  12 . 
         [0024]    Referring particularly to  FIG. 2 , each lift arm  20  is connected to a plate  28  that is pivotally mounted to agricultural harvester  10  at  30  and which is connected to an actuator  32 , shown as dashed line, to pivot the plate  28  and lift arm  20  about pivot point  30 . The lift arm  20  has an upwardly facing U-shaped recess  34  at its far end which receives a mounting pin  36  secured to the rearward face of frame  22 . The upwardly facing U-shaped recess  34  enables the header  18  to be connected and disconnected to the agricultural harvester  10 . 
         [0025]    Referring now to  FIG. 3  the tilt cylinder  26  is illustrated. Tilt cylinder  26  comprises a hydraulic cylinder  40  having an extendable rod  42  connected to an internal piston (not shown) for varying the overall length of the tilt cylinder. The end of the extendable rod  42  has a hook assembly  44  with a downward facing hook and a finger latch  46  that allows the downward facing hook assembly  44  to embrace a cross pin, such as the pin  38 , and spring back to its illustrated position to lock it in place. The cylinder  40  has a head or barrel end hydraulic line  48  connected to its barrel end and a rod end hydraulic line  50  connected to the rod end for supplying hydraulic fluid at an appropriate pressure. Lines  48  and  50  extend to a controller schematically illustrated at  52  for a function to be later described. 
         [0026]    In accordance with the present invention, a perch assembly  54  illustrated in  FIGS. 4 and 5  is employed to allow the tilt cylinder  26  to be remotely connected to the header  18 , including avoiding the need to leave the operator cab  14 . In  FIG. 4 , the hydraulic cylinder  40  has an integral plate  68  at its base that is positioned between a pair of actuator supports  70  appropriately secured to frame  12  to mount the tilt cylinder  26  for pivoting movement about axis A through an appropriate pin. 
         [0027]    The perch assembly  54  includes a pair of arms  56  extending from and pivotally connected to frame  12  about axis A to a cross perch  58  in the form of a plate. As shown particularly in  FIG. 5 , the cross perch  58  has a central recess  64  which conforms to the cross-sectional shape of plate  68  to accurately position the tilt cylinder  26  relative to the agricultural harvester and the header  18 . Recess  64  is intersected by a pair of ramps  66  that allow the plate  68  to be accurately and positively directed into recess  64  as the perch assembly  54  is moved to an elevated installation position. A bushing  59  is attached to one of the arms  56  to provide sufficient clearance away from the actuator supports  70  for articulated movement. The arms  56  each have a crank arm  60  extending radially outward from axis A to enable pivotal movement of perch assembly  54  from a perch actuator  62 , particularly shown in  FIGS. 3 and 4 . 
         [0028]    The perch actuator  62  may be employed in one of a number of different forms. For example, it may be electric, pneumatic, a linear motor, all with the purpose of manipulating the perch assembly  54  to elevate the tilt cylinder  26  to a position where it does not interfere with the lift arms  20  for the header  18 . The actuator may be conveniently controlled from the operator cab thereby eliminating the need for the operator to dismount. 
         [0029]    Although the other forms of the perch actuator  62  may be employed, it is shown herein as a hydraulic actuator, particularly shown in  FIG. 6  and in  FIG. 3 . Referring first to  FIG. 3 , the perch actuator  62  includes a hydraulic cylinder  72  and an extendible rod  74  connected to crank arm  60  by a connecting pin  76 . A barrel end  78  hydraulic line and a rod end hydraulic line  80  are each connected to the control system  52 , herein illustrated as a hydraulic control system. 
         [0030]    The hydraulic control system  52  includes a lift pump  82  providing pressurized fluid to an output line  84  and whose pressure is regulated by pressure regulator  86  and return line  88  which extends to a drain line  90  and then to a reservoir  92 . Output line  84  extends to a valve  94  that controls a portion of the output of the lift pump  82 . Line  96  connects with output line  84  and extends to a tilt cylinder valve  98  that prevents or allows flow to the rod end line  50  of the tilt cylinder  26 . 
         [0031]    A charge pump  100  pressurizes fluid for delivery to an output line  102  and whose pressure is regulated by a pressure regulator  104  connected to return line  106  that leads to reservoir  92 . Nominally, the output pressure of the lift pump  82  is regulated to about 3200 psi and the output pressure of charge pump  100  is regulated to about  400  psi. Output line  102  connects with line  108  that connects with the barrel end line  48  of the tilt cylinder  26  and to a valve  110  that is connected to the barrel end line  78  and rod end line  80  of the perch actuator  62 . 
         [0032]    In operation, the agricultural harvester  10  is directed to the header  18  and the lift arms  20  engaged. At this point, the tilt cylinder  26  is to be elevated to a point where it is out of the way of the connecting pin  38  on arm  24  of header  18 . The operator activates the perch valve  110  from its illustrated deenergized position into a position where the charge pressure from pump  100  is directed to the barrel end of perch actuator  62  and the rod end line  80  is directed to the drain line  90  this causes the rod  74  to be extended to its maximum length which, in turn, pivots the perch assembly  54  to an elevated position for installation of the header  18 . In this position, the downward facing hook  44  is above the connecting pin  38  of header  18 . It is assumed, that in this position, the tilt cylinder is extended sufficiently for the hook  44  to be beyond the mounting pin  38 . When the operator is ready to lower the tilt cylinder  26  to engage the pin  38 , the perch valve  110  is deenergized which then provides, in the illustrated position in  FIG. 6  charge pressure to the rod end of perch actuator  86  and connects the barrel end to drain line  90 . This cause the perch actuator  62  to positively lower the perch assembly  54  to its lower operational position that permits normal operation of the tilt cylinder. 
         [0033]    At this point, the tilt cylinder  26  will be resting on the pin  38  and the operator will retract the tilt cylinder  26  by energizing the master valve  94  and valve  98  to provide lift pressure to the rod end of the tilt cylinder  26  which retracts and causes the latch  46  on the downward facing hook  44  to engage and lock with the mounting pin  38 . During normal operation of the agricultural harvester  10 , the master valve  94  and tilt cylinder valve  98  are de-energized which locks the position of the tilt cylinder  26  and returns the lift pressure flow to the reservoir  92 . The tilt cylinder  26  may be extended by energizing the tilt cylinder valve  98  only, allowing flow from the rod end of tilt cylinder  26  to the reservoir  92 . 
         [0034]    The valves  94 ,  98  and  110  are illustrated as solenoid valves that may be conveniently controlled by electrical signals generated in operator cab  14 . Such controls are not illustrated to enable a clearer understanding of the invention. 
         [0035]    The above arrangement allows for a remote connection of the tilt cylinder  26  to the header  18  without the need for an operator to dismount from the operator cab  14 . This greatly increases the overall efficiency of the agricultural harvesting operation. The perch assembly  54 , by virtue of the recess  64  and ramps  66 , provides a positive and accurate alignment with tilt cylinder  26  as it is being moved to its elevated installation position. Such accuracy is necessary to result in correct and repeatable placement of the downward facing hook  44  and latch  46  with the pin  38 . Furthermore, when the perch assembly  54  is in its lower operational position it is positively held there by the hydraulic system pressure to prevent any contamination which may affect efficient operation. 
         [0036]    While this invention has been described with respect to at least one embodiment, 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.