Abstract:
A product distribution device shown as an agricultural air seeder in which product distribution can be selective stopped and started in sections of the machine width. The functioning of the section control system is monitored by sensors that directly detect the control member position as opposed to sensing the commanded position of the control member. Likewise, in generating a map of the area covered, the actual detected position of the control member is used instead of the commanded position of the control member. An operator is notified of inconsistencies between the commended position of the control member and the sensed position.

Description:
FIELD 
       [0001]    The following relates to a product distribution device, such as an agricultural air seeder, having section control and a monitor for the section control. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0002]      FIG. 1  is a side elevational view of an air seeder and tilling implement; 
           [0003]      FIG. 2  is a perspective view of the seed meter shown in  FIG. 1 ; 
           [0004]      FIG. 3  is an exploded perspective view of the meter cartridge illustrating one meter casing and one roller segment separated from the cartridge; 
           [0005]      FIG. 4  is a perspective view of the seed meter casing illustrating the gate in the closed position; 
           [0006]      FIG. 5  is a perspective view of the seed meter casing shown in  FIG. 4  illustrating the gate in the open position; 
           [0007]      FIG. 6  is a side sectional view of the seed meter of the air seeder shown in  FIG. 1 ; 
           [0008]      FIG. 7  is a perspective view of the primary distribution manifold; 
           [0009]      FIG. 8  is a sectional view of the primary distribution manifold of  FIG. 7 ; 
           [0010]      FIG. 9  is a fragmentary sectional perspective view of a portion of the distribution manifold of  FIG. 7 ; 
           [0011]      FIG. 10  is a schematic diagram of the control system for the product distribution system. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    A product distribution device is provided and described below. One application of such a device is an agricultural air seeder. 
         [0013]    Referring to  FIG. 1  an agricultural seeding and fertilizing implement  10  commonly referred to as an air seeder is shown. Implement  10  includes an air cart  11  having containers or tanks  12  and  14  for containing products to be distributed to the soil. The tanks  12  and  14  are mounted on a frame  16  supported by ground wheels  18  for forward movement over the ground by a towing vehicle (not shown) connected to a forward tongue  20 . Any number of tanks can be provided on the air cart. A ground-engaging tool  24  includes a frame  26  supported by ground wheels  28  and is connected to the rear of the air cart frame  16  by a tongue  30 . Alternative arrangements may place the ground engaging implement in front of the air cart  11  or the air cart and the ground engaging tool can be combined onto a common frame. The tanks  12  and  14  can be any suitable device for holding the material to be dispensed. They could be hoppers, bins, boxes, containers, etc. The term “tank” shall be broadly construed herein. Furthermore, one tank with multiple compartments can also be provided. 
         [0014]    An air distribution system  34  includes a fan  36  connected and a product delivery conduit structure having multiple product flow passages  38 . The fan  36  directs air through the passages  38 . A product meter assembly  40 , located at the bottom of each tank  12  and  14 , only one of which is shown in  FIG. 1 , delivers the products from the tanks  12  and  14  to a primary manifold  42 . In the manifold  42 , the product enters into the passages  38  and the stream of air moving through the passages  38 . As will be described below, there are multiple passages  38 , each associated with one section of the meter. The particular type of meter is not important to the product distribution device, however, in most instances, the meter will be a volumetric meter. An example of such a distribution device is the John Deere 1910 Commodity Air Cart which is shown in detail in U.S. Pat. No. 6,213,698, incorporated herein by reference. 
         [0015]    Each passage  38  carries product rearwardly in the air stream to a secondary distribution tower  50 . Typically, there will be one tower  50  for each passage  38 . Each tower  50  includes a secondary distributing manifold  52  located at the uppermost end of a vertical tube  54 . The distributing manifold  52  divides the flow of product into a number of secondary distribution lines  58 . Each secondary distribution line  58  delivers product to one of a plurality of openers  60  attached to the frame  26  at transversely spaced locations to deposit the product in the ground. A firming or closing wheel  62  associated with each opener  60  trails the opener and firms the soil over the product deposited in the soil. The implement  10  may be equipped with separate passages  38  for each of the tanks  12  and  14  as shown whereby different products can be distributed separately. Alternatively, the products from tanks  12  and  14  can be combined in the same set of passages  38  for distribution together. In other embodiments of the distribution system, the passages  38  may be selectively configurable to combine the products from tanks  12  and  14  into common passages or to keep the products separate in different passages  38 . In the air cart  11  shown in  FIG. 1 , the manifold  42  is configurable to direct product into either an upper rank of passages  38  or into a lower rank of passages  38 . The manifold  42  of the tank  14  is likewise configurable to mix or keep separate the products from the two tanks. 
         [0016]    The meter assembly  40  will now be described in greater detail with reference to  FIGS. 2-6 . Meter assembly  40  includes a meter housing  70  having an upper end  72  that is coupled to the lower end of the product tank  12 . The housing  70  further has a lower end  74  that is coupled to the primary manifold  42  of the pneumatic distribution system. The housing  70  has an inlet passage  78  through which product is received into the housing and an outlet passage  80  through which metered product is delivered to the distribution system. A rotary cut off valve  82  is placed in the inlet passage  78  and can be rotated as shown by the arrow  83  from the open position shown in  FIG. 6  to a cleanout position in which product is discharged from the housing  70  to enable the product tank  12  to be emptied without the product flowing through the meter assembly to the distribution system. 
         [0017]    The inlet passage  78  leads to a meter cartridge  90  which houses a meter roller  92 . The cartridge  90  is removable from the meter housing  70  as shown in  FIG. 2  where the cartridge  90  is shown partially withdrawn from the meter housing  70 . The cartridge  90  consists of a plurality of meter casings  94  placed adjacent to one another and fastened together by elongated bolts  96 ,  FIG. 3 , extending through apertures  98  in the meter casings. The meter roller  92  is constructed of a plurality of roller segments  100  axially positioned along a drive shaft  102 . In the embodiment shown, the drive shaft  102  is hex shaped to mate with the hex shaped bore  104  in the roller segments  100 . Additional attaching hardware is shown and described in U.S. Pat. No. 5,878,679 incorporated herein by reference. 
         [0018]    Each roller segment  100  is disposed within a separate meter casing  94 . Each meter casing  94  has a radial wall  106  along one axial end of the casing  94  that separates adjacent roller segments  100  from one another axially along the shaft  102 . Each casing  94  defines an inlet  108  in communication with and aligned with the inlet passage  78  of the meter housing  70  for receiving product therefrom. As the meter roller  92  rotates, as shown by the arrow  110  in  FIG. 6 , product is displaced by the teeth and grooves  112  of the rollers, over the ledge  114  to the outlet  116  in the meter casing. Product flow over ledge  114  only occurs when the shut-off gate  140  is in an open position as described below. From the meter cartridge outlet  116  product flows to the outlet passage  80  in the meter housing and to the manifold  42  of the distribution system  34 . 
         [0019]    With reference to  FIGS. 7-9 , the manifold  42  has an upper end  120  which is fastened to the lower end  74  of the meter housing  70 . The manifold has eight cavities  124  at the upper end that align with the eight cavities  84  of the outlet passage  80  in the meter housing. The manifold  42  has an upper rank  126  of tubes  128  that connect to an upper rank of the product flow passages  38 . The manifold further has a lower rank  130  of tubes  132  that connect to a lower rank of passages  38 . An adjustable valve  134  is slidable in the manifold and has convex valve members  136  that direct the product to either the upper rank or the lower rank of tubes. The valve  134  is shown in one position in  FIG. 8  directing the product to the lower rank  130  of tubes and in the opposite position in  FIG. 9  directing the product to the upper tubes. 
         [0020]    With reference to  FIGS. 4-6 , each meter casing  94  has a control member in the form of a shut-off gate  140 . Each control member is movable between an open position and a closed position. In the open position the control member allows flow of product through the meter housing  70  and into the associated product flow passage  138 . In the closed position, the control member stops flow of product in the product flow passages. In the embodiment shown, a shut-off gate  140  in  FIG. 4  is shown in the closed position preventing product from flowing over the ledge  114 . The shut-off gate  140  is pivotally mounted to the meter casing at pivot  142  near a proximal end of the gate. Each gate  140  is held in the closed position by a plunger  146  that is moved within a sleeve  148  in the meter casing  94 . Actuators  150  are mounted to the meter housing  70 . Each actuator  150  has an extendable rod  152  that extends into the sleeve  148  and bears against the plunger  146  as shown in  FIG. 6  when the actuator is in the energized state. While the shut-off gate  140  is shown as a pivoting gate, it will be appreciated that the shut=off gate could mounted for sliding or other types of movement between the closed and open positions. The claims that follow are not limited to the particular form of motion of the shut-off gate or control member. 
         [0021]    A meter casing and shut-off gate are shown in greater detail in  FIGS. 4 and 5 . In  FIG. 4  the gate  140  is shown in the closed position in which a distal end  154  of the gate bears against or is adjacent the ledge  114  to prevent product from flowing over the ledge. In  FIG. 5 , the gate is shown in the open position, spaced from the ledge  114 , allowing product to flow over the ledge to the outlet passage  80 . The gate  140  is biased by a spring mechanism, not shown, to the open position so that in a failure mode of the actuators  150 , the machine can still be used to distribute product only without the ability to stop sections of the meter to avoid product overlap. More details of the gate structure and the actuators can be found at U.S. Pat. No. 8,678,347, incorporated herein by reference. 
         [0022]    The gate  140  is operable to stop flow of the product by blocking the meter casing outlet. Other mechanisms for doing the same are described in U.S. Pat. Nos. 8,132,521 and 8,281,724 which show other gate mechanisms for closing the meter outlet, both of which are incorporated herein by reference. Product flow can also be stopped by blocking the flow of product into the meter as described in U.S. Pat. No. 7,690,440 also incorporated herein by reference. Product flow can further be stopped by stopping the rotation of one or more meter roller segments  100 . A device for doing so is shown in U.S. Pat. No. 8,196,534 incorporated herein by reference. Other means may be used to disconnect sections of a meter roller from the drive. One example of this is the Zone Command and Auto Zone Command™ available from Seed Master of Emerald Park, Saskatchewan, Canada, which uses an air cylinder to disengage gears on the metering rollers to stop and start the product flow. Product flow through the product flow passages can also be stopped by control means located in the product flow passages downstream of the meter. For example, U.S. Pat. No. 7,555,990, incorporated herein by reference, shows valves diverting the flow of product from the secondary distribution lines  58  to stop the product flow. All of the above mechanisms include a control member that is movable between open and closed positions to either allow or stop flow of product to the product flow passages. 
         [0023]    During operation of the implement  10 , it is important to know that the control member or gate  140  is in the proper position. If the control member is in its closed position when it is supposed to be open, an area of a field will not be covered or planted with seed. Conversely, if the control member is in the open position when it is commanded to be closed, there will be wasted product. Seed Hawk, of Langbank, Saskatchewan makes an air cart embodying the device shown in U.S. Pat. No. 7,690,440. To monitor the location of the shut off gates, a sensor is placed on the gate actuator to monitor the position of the actuator. While this is helpful, it does not work properly to inform the operator of the control member position in the event of a failure of the connection between the actuator and the control member. 
         [0024]    A monitoring system is provided to overcome this problem by directly sensing the position of the control member, such as the gate  140 . By “directly” sensing the control member position, it is meant that the position of the control member itself is sensed, not the position of the actuator or linkage connected between the control member and the actuator. Thus, regardless of any failure of the actuator or linkage, the operator is always informed concerning the actual position of the control member. 
         [0025]    In the device shown in the Figures, the control member position sensing is accomplished with the use of proximity switches associated with each control member or gate  140 . A magnet  202  is affixed to or integrated into each control member. A tube  204  extends through the meter casings  94  and contains reed switches  206  for each shut-off gate  140  and magnet  202 . The reed switches are a type of proximity sensor that is activated by the presence of the magnet. In this instance, the reed switch is a non-contact switch as it does not make contact with the control member. In this embodiment, when the shut-off gate  140  is in the open position, the magnet is close enough to the switch to act on the switch to close the electrical circuit. The closed circuit generates a signal to the controller  222  (see below). When the shut-off gate is in the closed position, the magnet is sufficiently far away from the reed switch that the switch remains in the open position and no signal is generated. The tube  204  contains the lead wires for multiple switches so that one switch is placed in each meter casing  94  for detecting the position of each control member or gate  140 . The tube  204  encloses the reed switches and isolates the switches from the environment and from contamination from the product being distributed. The tube may be made of any suitable material that allows the magnetic field of the magnets  202  to pass into the tube. Stainless steel is one suitable material. The tube and reed switches are available from Elobau GmbH. By activating the reed switches  206  based on the position of the gates, the gate position is sensed directly instead of sensing the position of another component that is connected to the gate. This avoids any signal errors caused by mechanical failures. Other types of contact and non-contact position sensors may be used in place of the magnets and reed switch combination described here. 
         [0026]    The direct sensing of the control member position can be done with control members at any location in the distribution system. For example, the control members maybe between the tanks and the meter to prevent product flow into the meter. In another embodiment, the control member may be a distance downstream from the meter. One option is to place the control member at a distribution manifold such as the manifold  52 . In all embodiments, the claimed “product flow passage” is a passage downstream of the control member or gate  140 . 
         [0027]    A schematic diagram of the control system is shown in  FIG. 10 . A monitor  220  contains a micro-processor based controller  222 , a display  224  and a memory device  228 . The display can be a touch screen to operate as both an output device and an input device. Other input devices may be used such as push buttons or rotary knobs. The controller is connected to the actuators  150  to command either open or closed positions for the control members. Likewise, the reed switches  206  are coupled to the controller so that the controller receives position signals from the sensors indicating the position of the control members. The display  224  is used to display an alert message to the operator if the commanded position of any control member is inconsistent with sensed position of the control member. An inconsistency can occur in two different situations. In once inconsistency, the commanded position of the flow control member is open and the sensed position is that the flow control member is closed. The second inconsistency occurs if the commanded position for a flow control member is closed and the sensed position is open. The control system can be configured to alert the operator in the event if either the first or the second inconsistencies or both. Those skilled in the art will recognize that audio or tactile alarms are also possible. 
         [0028]    A location signal input is provided by a positioning system such as GPS  226 . Any type of local or satellite positioning system can be used. The controller stores in the memory map data showing the geographic area over which product has been distributed. The map is based on the position of the device, i.e. the area over which the tool  24  has covered, and the actual sensed positions of the shut-off gates  140 . This produces a more accurate coverage map than if the map is based on the commanded position of the control members since the actual position of the control members may vary from the commanded position. The schematic diagram of the control system in  FIG. 10  is only illustrative of one way to construct such a system. Those skilled in the art will recognize, for example, that the various components in the monitor  220  can be separately housed and located if desired. 
         [0029]    Having described one embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.