Abstract:
A harvesting machine includes a crop intake arrangement including either a reel or a crop hold down which operate to aid in the advancement of harvested crop into the machine for further processing. In the event of a jam or the presence of metal occurring, the crop intake arrangement may be operated in reverse so as to expel the jam and/or sensed metal. An actuator is provided for moving the reel or crop hold down between non-operating and operating positions and a first sensor for sensing a jam condition and/or the presence of metal is provided which sends a signal when such a condition exists, this signal being used to effect automatic operation of said actuator so as to move the reel or hold down to a non-operating position so as not to interfere with the expulsion of the jam and/or metal. Other controls are provided and other parameters are sensed for delaying and/or overriding the automatic positioning of the reel or crop hold down in their non-operating position. One such parameter is provided by a timing device which prevents automatic positioning of the reel or crop hold down when the signal indicating a jam or the presence of metal does not endure for a pre-selected time interval. Another parameter is provided by a sensing device which determines whether or not the machine is traveling in the forward direction. If it is, after a jam or the presence of metal is sensed, then a signal is issued which causes the reel and/or hold down to be returned to its operating position.

Description:
The invention concerns a harvesting machine with a crop intake arrangement that can be reversed in order to remove a jam and/or the intrusion of undesirable materials, and that is equipped with a supply element, whose position can be changed from an operating position to a non-operating position. 
     BACKGROUND OF THE INVENTION 
     In combines, forage harvesters and other agricultural harvesting machines, various differing front attachments, for example, pick-up and cutter platforms or heads, are used to supply the harvested crop material. Hold downs attached to the pick-up in various configurations or the reel attached to a cutter platform for grain crops on a combine provide for an improved intake and thereby the uniform processing of the harvested crop. In the state of the art, forage harvesters are protected as a rule against damage or destruction of the knife drum or other significant components by metal detectors. If a reversal of the crop intake arrangement becomes necessary due to the response of the metal detector, the hold down must be raised so as to avoid interference with the ejection of the harvested crop. With an unexpectedly high crop supply, the crop intake arrangement can encounter jams particularly if the full power capability of the machine is utilized. In this case, a reversal of the crop intake arrangement is also necessary which requires the raising of the reel of a combine or the hold down of a pick-up. The raising must be performed by the operator most appropriately before the reversal or simultaneously with the start of the reversal process. As a rule, separate known operating arrangements are provided for the reversal and the raising of the reel or the hold down, which makes the operation relatively cumbersome. 
     In EP-403 889 A, it is proposed that a reversing gear and an arrangement for the removal of a hold down from the operating region of a collecting drum be controlled by a common switch. However, the raising of the hold down will not be desirable in all cases in which reverse operation is performed. Since the hold down is raised only with the activation of the reverse operation, it is also conceivable that crop may jam at the beginning of the reverse operation. This condition would not be feared if the hold down had been raised earlier, however, this is not possible with the control arrangement described. 
     The problem underlying the invention is seen as that of the known harvesting machines having reels or crop hold downs which do not operate in an entirely safe or efficient manner especially when the feeding of crop must be reversed. 
     SUMMARY OF THE INVENTION 
     According to the present invention, there is provided an improved arrangement for use with a harvesting machine which ensures free ejection of crop or metal from the machine by reversing crop feed elements of the intake arrangement. 
     A more specific object of the invention is to provide a harvesting machine, as discussed above, equipped with a jam sensor and/or an undesirable material detector which each produce a signal when a jam or undesirable material is present, and to use this signal in a control arrangement, such as to cause a reel or a crop hold down to be moved to a non-operating position so as to permit the free flow of crop and/or undesirable material upon reversal of the crop feed elements. 
     Yet another object of the invention is to provide a harvesting machine, as defined in the immediately preceding object, wherein the control arrangement is coupled for receiving a timing device signal so as to effect operation to block movement of the reel or crop hold down to their respective non-operating position unless the signal indicating a jam or the presence of metal persists for a predetermined time interval. 
     Still another object of the invention is to provide controls whereby an operator may take overt action for overriding the movement of the reel or crop hold down to their respective non-operating position. 
     These and other objects will become apparent from a reading of the ensuing description together with the appended drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a left side elevational view of a combine equipped with a control arrangement constructed in accordance with the principles of the present invention. 
     FIG. 2 is a left side view of a crop intake arrangement for the combine of FIG.  1 . 
     FIG. 3 is a top plan view of the crop intake arrangement of FIG.  2 . 
     FIG. 4 is a block diagram of the circuit embodying a control arrangement of the combine of FIG.  1 . 
     FIG. 5 is a left side elevational view of a forage harvester equipped with a control arrangement constructed in accordance with the principles of the present invention. 
     FIG. 6 is a block diagram of the circuit embodying the control arrangement of the forage harvester of FIG.  5 . 
     FIG. 7 shows a flow diagram of the operational steps effected by the control arrangement. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, there is shown a harvesting machine in the form of a combine  10  supported on front driven wheels  12  and rear steerable wheels  14 . An operator&#39;s cab  16  is supported ahead of a grain tank  18  and its discharge pipe  20  on a frame  22 . Located beneath the cab  16  at the front of the frame  22  is a thresher drum  24 , a thresher stator  26  and a deflecting drum  28 ; and following these elements for the further separation of grain from the straw are shakers  30 , a preparation chute and sieves  34 . Finally the threshed out portion of the crop is conveyed into the grain tank  18 , the large crop components are deposited on the ground over the rear end of the shakers  30  and the lighter components are blown from the sieves  34  and also onto the ground by means of a blower  36 . After being taken up from the ground by a crop intake arrangement  50  shown in FIG. 2, crop lying or standing on the ground is conducted over a slope conveyor  38  and a stone catcher trough  40  the thresher drum  24 . 
     From the view point of forward harvesting operation of the combine  10 , crop intake arrangement  50 , shown in FIG. 2, is fastened, so as to be removable, to the forward surface of the slope conveyor  38 . As a rule this removable fastening is accomplished by hooks. The crop intake arrangement  50  is equipped with a sickle bar arrangement  58  for the cutting of crop, in particular grain crops, from the ground. The cut crop is conducted to a screw conveyor  52 , by a reel  54  which, as viewed in FIG. 2, is driven counterclockwise about a transverse axis  56 , the screw conveyor  52 , in turn, delivers the crop to the slope conveyor  38 . The reel  54  can be adjusted in its position through a telescoping rod  51  and a hydraulic cylinder  53 , in place of which a correspondingly controlled electric motor could be used. The reel  54  can be brought, by means of the hydraulic cylinder  53 , from a normal operating position, in which crop is taken in, into a non-operating position in which jammed crop can again be ejected by reversal of the slope conveyor  38 , the screw conveyor  52  and the reel  54 . In the non-operating position, the reel  54  is spaced a greater distance from the screw conveyor  52  than when in the operating position. The slope conveyor  38  is provided with a housing  60 , in which an endless conveyor chain  46  with intake rails  48  circulates about a lower slope conveyor roll or sprocket  42  and an upper slope conveyor roll or sprocket  44 . The latter roll  44  is supported on a shaft  62  and is driven by a drive coupled to the shaft  62 . The conveyor chain  46  with the intake rails  48  conveys the harvested crop, operating as an under shot conveyor into the combine  10 . 
     Referring now to FIG. 3, the drive elements for the slope conveyor  38  and the crop intake arrangement  50  can be seen. A shaft  64  is driven (as a rule indirectly) from an engine  65  (FIG. 1) of the combine  10 . The shaft  64  may be the shaft of the thresher drum  24  or the shaft of the deflecting drum  28 . A belt pulley  72  is fastened to the shaft  64  and carries a triple belt  66 . In addition, the belt  66  runs about a belt pulley  68  that is connected with a coaxial belt pulley  70  about which a further belt  74  circulates. The belt pulleys  68  and  70  are penetrated by the shaft  62  of the upper slope conveyor roll  44 . At the end opposite the belt pulleys  68  and  70 , the shaft  62  is connected over a chain sprocket  92 , a chain  90  and a further chain sprocket  88  with a reversible motor  86 . An electric clutch (not shown) is arranged within the belt pulley  72  with which the belt pulley  72  can be coupled to and uncoupled form the shaft  64 . The chain sprocket  92  on the shaft  62  of the upper slope conveyor roll  44  is also equipped with an electric clutch (not shown) with which it can be coupled to and uncoupled from the shaft  62 . The belt  74  circulates about a belt pulley  76  positioned at the forward end of the slope conveyor  38 , which, for its part, drives a chain drive gearbox  78 . The chain drive gear box  78  drives a hexagonal shaft  80  that is connected, so as to be removable, to either side of the slope conveyor  38  with the sickle bar drive shafts  82 . The sickle bar drive shafts  82  are connected over gearboxes  84  with the sickle bar arrangement  58 . The axle  56  of the reel  54  can be driven by means of a hydraulic motor  94 , and the screw conveyor  52  can also be brought into rotation by a hydraulic motor  96 . 
     In normal harvesting operation, the electric clutch in the belt pulley  72  is engaged, and the engine of the combine  10  drives the shaft  62  of the upper slope conveyor roll  44  through the belt  66  and the belt pulley  68 . The sickle bar arrangement  58  is also driven by the engine through the belt pulley  70 , that is joined together with the belt pulley  68 , the belt  74 , the belt pulley  76 , the chain drive gear box  78 , the hexagonal shaft  80 , the sickle bar drive shafts  82  and the gear box  84 . The screw conveyor  52  is driven by the hydraulic motor  96 , and the reel  54  is driven by the hydraulic motor  94 . The electric clutch in the chain sprocket  92  is operated to disengage the drive connection between the reversible motor  86  and the shaft  62  of the upper slope conveyor roll  44 . In reverse operation, that is, in case jammed crop is to be ejected, the electric clutch in the belt pulley  72  is disengaged, and the electric clutch in the chain sprocket  92  is engaged. Then the reversible motor  86  drives the conveyor chain  46  of the slope conveyor  38  in the backward (reversed) direction, while the hydraulic motors  94  and  96  are also operated in the reverse direction. This reverse operation is known in itself and therefore does not require any detailed explanation. 
     According to the invention, the control circuit shown in FIG. 4 is provided on the combine  10 . A control arrangement  100  that may be a separate microprocessor or controller, or is part of the electronic control of the combine  10 , is connected to a jam sensor  102 , a switch  104  for the input of the position of the reel, a time function element  106  and an operating drive sensor  108 . Furthermore, the control arrangement  100  controls, through appropriate electrical and/or mechanical arrangements, the hydraulic cylinder  53 , that is used to adjust the position of the reel  54 . For the jam sensor  102 , for example, a torque sensor may be provided on the shaft  62  of the upper slope conveyor roll  44 , as shown in FIG.  2 . The switch  104  is arranged in the operator&#39;s cab  16  within reach of the operator, for example, on the instrument panel, an operating lever, a console or the like. The switch  104  is provided with a non-operating position, in which the reel  54  is brought into its non-operating position appropriate for reverse operation and ejection of jammed crop, and an operating position in which the reel  54  is in its operating position for normal harvesting operation. The operating drive sensor  108  is connected with one of the wheels  12  or  14  and transmits a corresponding signal to the control arrangement  100  when the combine is operated in the forward direction. The time function element  106  is triggered by the control arrangement  100  and transmits a corresponding signal back to the control arrangement  100  after a predetermined time interval. 
     The sequence of the functions of the control arrangement  100  is such that the hydraulic cylinder  53  is brought into the non-operating position for the reel  54  when the switch  104  is in its non-operating position. If the switch  104  is in the operating position, a test is made to determine whether the jam sensor  102  indicates a jam. If this is not the case, then the hydraulic cylinder  53  is activated and brings the reel  54  into the operating position. If the jam sensor  102  indicates a jam, then the reel  54  remains in the non-operating position and a malfunction is indicated to the operator through a corresponding indicating device. If the jam sensor  102  detects a jam during the harvesting operation, that is, at a time when the reel  54  is already in operation, then the time function element  106  is activated. After the time function element  106  of the control arrangement  100  has signaled the expiration of the predetermined time interval, for example, a few seconds, the control arrangement tests whether the operating drive sensor  108  has transmitted signals for the entire time interval or just then transmits a signal, indicating that the combine is operating in the forward direction. If this is the case, then the reel  54  remains in the operating position, otherwise it is brought into the non-operating position. Thereby the operator can, if necessary, prevent the automatic movement of the reel  54  into the non-operating position by simply continuing to operate in the forward direction, if a reverse operation does not appear necessary. The movement of the reel  54  into the non-operating position can also be prevented by a single actuation (turning it off and on) of the switch  104  within the time interval. Furthermore, it is conceivable that the reel  54  may also be brought into the operating position by the control arrangement  100  when the operating drive sensor  108  transmits a signal indicating forward operation, after the control arrangement  100  has been induced by the jam sensor  102  to bring the reel  54  into the non-operating position. 
     FIG. 5 shows a harvesting machine in the form of a self-propelled forage harvester  110  in which a control arrangement  100 ′ (FIG.  6 ), according to a second embodiment of the invention, is provided. The forage harvester  110  includes a frame  112  that is carried by front and rear wheels  114  and  116 , respectively. The forage harvester  110  is controlled from an operator&#39;s cab  118  from which a crop intake arrangement  120  can be seen and controlled by the operator. Crop taken up from the ground by means of the crop intake arrangement  120 , for example, corn, grass or the like, is conducted over feed rolls  130  arranged within an intake housing  132 , to a chopper drum  122  which chops the crop into small pieces and conducts it to a conveyor arrangement  124 . The crop leaves the forage harvester  110  to an accompanying trailer through a discharge duct  126  which may be swung about a substantially vertical axis. Between the chopper drum  122  and the conveyor arrangement  124 , a post-chopper reduction arrangement  128  extends, through which the crop to be conveyed is conducted tangentially to the conveyor arrangement  124 . 
     In this embodiment, the crop intake arrangement  120  is configured as a so-called pick-up and designed as an independent unit. However, this crop intake arrangement  120  could equally well be a supplementary attachment that is attached, for example, in a flange to the front region of the cutter head of a combine. The crop intake arrangement  120  is supported on the ground on support wheels  140 . The task for the crop intake arrangement  120  consists of picking up crop of the most diverse type and condition lying on the ground in windrows or swaths and to conduct it to the forage harvester  110  for further processing. For this purpose, the crop intake arrangement  120  is moved over the field during the harvesting operation at a small spacing from the ground, while it is raised for transport over a road or on paths. The crop intake arrangement  120  contains a conveying arrangement  134  in the form of a screw conveyor  134  that conveys, in a manner known in itself, the crop, that has been picked up, from the sides of the crop intake arrangement  120  to a delivery opening, not shown, located in the center, behind which the feed rolls  130  follow, to which the conveyor arrangement delivers the crop through a rotationally driven intake device  136 , arranged underneath the conveyor arrangement  134 , and raises the crop from the ground with its conveyor tines, in order to transfer it to the conveyor arrangement  134 , and a hold down  138  in the form of a sheet metal component arranged above the intake device  136 . Alternatively, the hold down  138  could be in the form of rolls or contain several rods. The rotational axis of the conveyor arrangement  134  and a pivot axis  143  of the hold down  136  extend parallel to each other and to the ground and transverse to the direction of operation of the forage harvester  110 . The relative position of the conveyor arrangement  134  to the intake device  136  cannot be changed. The relative position of the hold down  138  can be adjusted between the operating position, in which the hold down  138  is shown in FIG. 5 in solid lines, and in which the hold down  138  interacts with the intake device  136 , and a non-operating position, shown in dashed lines. For this purpose, a hydraulic cylinder  142  is provided (that could also be replaced by an electric motor), which pivots the hold down  138  correspondingly about a horizontal axis defined by a pivot pin  143 . The non-operating position of the hold down  138  is shown to be necessary in reverse operation, in which the feed rolls  130 , the conveyor arrangement  134  and the intake device  136  (optimally also the chopper drum  122 ) are operated in a direction of rotation opposite to the normal harvesting operation, in order to be able to eject jammed material. The reverse operation is performed, in a manner known in itself, with associated reversible motors. Even if a metal detector  145  (shown only in block form in FIG. 6 but not otherwise disclosed), that is arranged within one of the feed rolls  130 , responds, and stops the drive of feed rolls  130 , a reverse operation is still necessary to expel the metal material along with crop material. 
     FIG. 6 shows a circuit diagram in principle of the control circuit for the hydraulic cylinder  142  for the adjustment of the hold down  138 . A control arrangement  100 ′ is connected to a jam sensor  144 , the aforementioned metal detector  145 , that is stationary and arranged in the interior of one of the feed rolls  130 , a switch  146  installed in the operator&#39;s cab  118  for the input of the desired position of the hold down  138 , a time function element  148 , an operating drive sensor  150  and the hydraulic cylinder  142 . The control arrangement  100 ′ may be a separate microprocessor or a controller or it may be a part of the electronic control of the forage harvester  110 . The jam sensor  144  detects whether the feed rolls  130  and/or the chopper drum  122  are blocked by an excess of harvested crop supplied. Therefore, it measures the drive torque of one of the feed rolls  130  and/or the chopper drum  122 , and transmits a corresponding signal to the control arrangement  100 ′ when a threshold value is exceeded, which the latter interprets as a jam. The metal detector  145  is known in itself, and therefore does not require any further explanation. It transmits a corresponding signal to the control arrangement  100 ′, in case ferromagnetic material is conducted past the feed rolls  130 , which could damage the chopper drum  122 . Furthermore the metal detector  145  effects actuation of a device that mechanically blocks the feed rolls  130  in case of a response. The switch  146  is easily accessible for an operator within the operator&#39;s cab  118 , arranged on the instrument panel, an operating lever, a console or the like and is provided with an operating position, in which the hold down  138  is to be brought into the operating position. In addition the switch  146  is provided with a non-operating position for effecting operation of the hydraulic cylinder  142  so as to bring the hold down  138  into its non-operating position shown in dashed lines in FIG.  5 . The time function element  148  can be triggered by the control arrangement  100 ′ and transmits a signal back to the control arrangement  100 ′ after the expiration of a certain time interval (of a few seconds). The operating drive sensor  150  is connected to one of the wheels  114  and  116 , and transmits a signal to the control arrangement  100 ′ that contains information showing whether the forage harvester  110  is being operated in the forward direction. The control arrangement  100 ′ controls the hydraulic cylinder  142 , over appropriate electronic, mechanical and/or hydraulic components, for the adjustment of the position of the hold down  138 . 
     The operation of the control arrangement  100 ′ is generally identical to that shown in FIG. 4. A difference consists of the fact that not only the response of the jam sensor  144  ( 102  in FIG.  4 ), but also that of the metal detector  145  lead to the actuation of the time function element  148 . After the expiration of the cycle of the time function element  148 , the hold down  138  is brought into non-operating position by the hydraulic cylinder  142 , or not, depending on whether the operating drive sensor  150  detected a forward operation for the entire time interval of the operation of the time function element and on whether the switch  146  for the position of the hold down  138  was activated. 
     FIG. 7 shows a flow diagram to clarify the method of operation of the control arrangement  100 ′ of FIG.  6 . After the start in step S 1 , for example, with the starting of the forage harvester  110 , S 2  initially tests whether the switch  146  is in the operating position. If the result of the test is “no”, S 3  tests whether the hold down  138  is in the operating position; this can be performed by an appropriate sensor or an interrogation of a memory in which the last actual or required position of the hold down  138  is stored. If the hold down  138  is not in the operating position, step S 2  follows again. Otherwise, the hold down  138  is brought into the non-operating position, in step S 4 , which is performed by activating the hydraulic cylinder  142 . Thereupon, step S 2  again follows. If step S 2  has found that the switch  146  is in the operating position, then step S 5  follows, which tests whether the jam sensor  144  and/or the metal detector  145  have responded. If this is not the case, step S 6  follows, which tests (in the aforementioned manner) whether the hold down  138  is in the operating position. If that is the case, step S 2  follows again, otherwise step S 7  follows, in which the hold down  138  is brought into the operating position by means of the hydraulic cylinder  142 , whereupon step S 2  again follows. If in step S 5  the jam sensor  144  and/or the metal detector  145  has responded, then in step S 8  the time function element  148  is started, and step S 9  tests whether the switch  146  is actuated and the output signal of the operating drive sensor  150  is detected and step S 10  tests whether the time function element  148  has run its course. If this is not the case, step S 9  again follows, otherwise step S 11 , which tests whether the switch  146  has been actuated or whether the velocity at that point in time (or during the entire run of the time function element  148 ) is grater than zero. If the result is “yes” the hold down  138  is not raised and step S 2  follows. Otherwise step S 12  follows in which the switch  146  is brought into its non-operating position (by means of an appropriate electromechanical arrangement), and upon which step S 3  again follows. Then the hold down  138  is brought into the non-operating position and the switch  146  is switched into its non-operating position. The operator can then remove the jam or the metallic object that intruded by reversing the intake devices.