Abstract:
The apparatus is an improvement to a feederhouse on an agricultural combine. The apparatus has a first acoustic array having a first sounding board and acoustic sensor positioned beneath the front drum and feederhouse floor. There is a second acoustic array positioned behind the front drum and between the conveyor chain encircling the front and rear drums. The second acoustic array also has a second acoustic sensor and second sounding plate. The acoustic sensor detects the impact of a stone on the sounding plates. A signal is transmitted via a controller from the sensor to a solenoid controlling a stone trap door latch. When the door opens, a sled also rotates into contact with conveyor chain. This deflects any crop flow containing stones. To close the door, the feederhouse is raise and the door rotates into contact with the latch.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims domestic priority on U.S. Provisional Patent Application Serial No. 60/128,717, filed on Apr. 12, 1999. 
    
    
     BACKGROUND OF INVENTION 
     1. Field of Art 
     This invention relates to the improvement of a feederhouse on an agricultural combine. More specifically, the invention allows for the ejection of a stone from the feederhouse. 
     2. Description of Prior Art 
     Mechanical harvesting of grain has taken place for decades. However, efforts continue in the attempt to make harvesting operations more efficient and effective. A combine harvester generally includes a header, which cuts the crop. The header then moves the cut crop into a feeder house. The feeder house lifts the cut crop into the threshing and separation areas of the combine. The grain is separated from the stalk by a rotor or threshing system. The grain is then moved and stored in a grain tank. The chaff and trash are deposited from the rear of the combine. The grain stored in the grain tank is eventually discharged through a grain tank unload tube. An operator usually runs these various operations from a glass-enclosed cab. Typically, the cab is located above and behind the header and feederhouse. There are a variety of agricultural combine harvesters and their operations are well known in the art. For examples of such harvesters reference U.S. Pat. No. 4,846,198 which illustrates the conventional and twin rotor threshing and separating systems of a harvester as well as other major systems of the harvester. See also the New Holland Super Conventional Combines TX™66, TX™68, the New Holland TWIN ROTOR® combines TR® 89 and TR® 99 for examples of existing conventional and twin rotor harvesters. U. S. Pat. No. 4,332,262 also illustrates the primary systems of a conventional harvester. For further details regarding various agricultural harvester systems review U.S. Pat. Nos. 4,522,553, 4,800,711, 4,866,920, 4,907,402, 4,967,544 and 5,155,984. See also the New Holland corn head model 996 and the New Holland grain belt header model 994 for details regarding headers. 
     The previously mentioned a feederhouse typically consists of a conveying chain which pushes the cut crop from the header to the front of the threshing system. The conveying chain has several crosspieces to assist in moving the crop and to ensure proper spacing. The conveying chain is powered and also positioned by a front drum and a rear drum. The front drum is positioned approximately behind the header and the rear drum is positioned approximately in front of the threshing system. As seen in FIG. 1, the drums rotate in a counter-clockwise fashion. The cut crop flow or crop mat is pushed by conveyor chain upwards along the floor of the feederhouse and towards the threshing system. Besides lifting or elevating the cut crop to the threshing and separating systems, the feederhouse provides several other functions. First, the feederhouse helps to properly position the header relative to the ground. Second, the feederhouse can be the location of a stone detection and removal means. Frequently, during farming operations, the header will inadvertently receive a stone. If the stone enters the threshing system in the combine, expensive damage will result to the threshing components. It is a critical function of a stone detection and removal system to prevent a stone from damaging the threshing system. A typical stone detection and removal system is a cylindrical stone beater or stone roll positioned near the mid-point of the feederhouse. The stone roll rotates allowing the crop mat to continue towards the rear drum and threshing system. A stone that is too large is forced from the feederhouse through a stone trap door beneath the stone roll. 
     Unfortunately there are several deficiencies to the current feederhouse design. The stone beater design limits the thickness of the crop flow. By limiting the amount of crop flow, it takes longer to perform farming operations. Previously, acoustic instruments have been used to detect stones entering farm equipment. Typically, the stone contacts a sounding plate. The acoustic instrument monitors the sounding plate. A stone contacting the sounding plate causes the sounding plate to emit a sound above a predetermined setting. The acoustic instrument observes this sound and halts the farming operation. It has been difficult to apply this technique of stone detection to a combine harvester. Typically if a single acoustic instrument and sounding plate is used, a stone can only be detected on the side of the crop flow closest to the detector. Stones on the opposite side or center of the crop flow are undetected. There are also additional problems with the feederhouse design. Conventional stone traps remain unlatched during farming operations. A malfunction with the spring mechanism used to keep the door closed can result in crop being inadvertently forced through the stone trap door. 
     The prior art illustrates these and other short-comings. U.S. Pat. No. 3,675,660 discloses a combine stone trap door premised on the rock detector circuit opening the stone trap door. It is possible that that the stone may be embedded in the crop flow and not deflected to be discharged. U.S. Pat. No. 4,275,546 discloses a stone discriminator using a single sounding plate to detect stones. This approach is unable to detect stones in the upper portion of the crop flow. It has not been able to successfully detect and eject stone sufficiently to be commercially viable. U.S. Pat. No. 4,288,969 discloses an improved stone trap seal. However, because of the angle of the conveying chain, a greater amount of crop is deflected and wasted. U.S. Pat. No. 4,294,062 discloses single sensing bar positioned at the bottom of the feederhouse and unable to sufficiently detect stones. U.S. Pat. Nos. 4,305,244, 4,322,933 and 4,343,137 illustrates a feeder house design for a combine. The lower sensing bar is used to trigger the stone trap door. However, the single sensing bar does not sufficiently detect the stones and the angle of the conveying chain results in more crop being deflected than necessary. U.S. Pat. No. 4,355,565 uses a mechanical stone beater bar to force a stone out of the crop flow. However, if the stone is too small or flat, the stone will not be detected or ejected. Also, the stone beater is only effective at lower speeds. U.S. Pat. No. 4,353,199 illustrates a single sensing bar used in a forage harvester. U.S. Pat. No. 4,768,525 illustrates a stone ejection door mechanism for harvesting equipment having a front and rear stone trap doors. U.S. Pat. No. 4,720,962 illustrates a single sensor that can be positioned in a variety of locations on a forage harvester. U.S. Pat. No. 5,702,300 illustrates a combine rock door over center closure apparatus shows a lever used to control a stone trap door. 
     An invention that could resolve these issues would represent an improvement to the art. 
     OBJECTS OF THE INVENTION 
     It is an object of the present invention to provide an acoustic stone trap detection system that can detect and eject stones. 
     It is an object of the present invention to provide two acoustic arrays that are capable of detecting stone located on the top and bottom of the crop flow through a feederhouse. 
     It is an object of the present invention to provide an acoustic stone detector that has one acoustic sensor positioned behind the front drum and between the conveyor chains. 
     It is an object of the present invention to provide a stone trap door that is positively latched during farming operations. 
     It is an object of the present invention to provide a stone trap door with a stone ejection sled. 
     It is an object of the present invention to provide a latch for a stone trap door controlled by a solenoid. 
     It is an object of the present invention to provide a controller capable of receiving an electrical signal from an acoustic sensor and transmitting an electrical signal to a solenoid. 
     It is an object of the present invention to provide a first acoustic array positioned beneath the feederhouse floor. 
     It is an object of the present invention to provide an improved sounding plate for the first acoustic array. 
     It is an object of the present invention to provide a method for detecting and ejecting a stone from a feederhouse of an agricultural combine. 
     SUMMARY OF THE INVENTION 
     The invention is an improvement to the feederhouse on an agricultural combine. The invention consists of a stone detection and ejection system on the feederhouse of an agricultural combine. The invention consists of a first acoustic array positioned beneath the front drum and having an acoustic sensor and first sound plate. The sounding plate is generally parallel to the feederhouse floor. There is a second acoustic array positioned between a conveyor chain encircling the front and rear drums. This array also has an acoustic sensor and sounding plate. The acoustic sensor used is an accelerometer that monitors the noise level of material impacting the sounding plates. When a stone impact is detected a sensor signal is sent via a controller to a latch to a stone trap door. The acoustic sensor in the second acoustic array is protected from the conveyor chain by a roller and roller support. The sensors are insulated from the rest of the feederhouse to prevent the sensors from detecting stray noise. After the solenoid releases the stone trap door latch, the door swings open and also pulls a stone ejection sled into contact with the conveyor chain. This deflects any crop flow with stones through a feederhouse floor aperture. By raising the feederhouse, a door cable rotates the door closed and re-latches the door to the feederhouse. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     The advantages of this invention will be apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
     FIG. 1 is an over-all side elevation of a combine equipped with a feederhouse and a header. 
     FIG. 2 is an enlarged side elevation of the feederhouse. 
     FIG. 2A is an enlarged view of the second acoustic array taken on line  2 A— 2 A of FIG.  2 . 
     FIG. 3 is an over-all side elevation of a combine equipped with a feederhouse showing the rotational movement of the stone trap door. 
     FIG. 4 is an over-all side elevation of a combine equipped with a feederhouse showing the rotational movement of the feederhouse where the door cable pulls the stone trap door closed. 
     FIG. 5 is a cut-away, close-up view of the first and second acoustic arrays. 
     FIG. 6 is a cut-away, close-up view of the first and second acoustic arrays showing a crop flow with stones passing through the feederhouse. 
     FIG. 7 is a schematic illustrating the controller and wires from the acoustic sensors and to the solenoid. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, it is possible to observe the major elements and general operation of the present invention. Left and right references are used as a matter of convenience and are determined by standing at the rear of the combine and facing the forward end in the normal direction of travel. Likewise, forward and rearward are determined by normal direction of travel of the combine. Upward or downward orientations are relative to the ground or operating surface. Horizontal or vertical planes are also relative to ground. 
     As seen in FIG. 1, the invention is located on a typical twin rotor combine  1  having a pair of front wheels  8  (only one shown) and a pair of rear wheels  9  (only one shown) for providing movement over the ground. At the front of the combine is a header  12  for cutting a crop. As the combine  1  and header  12  are moved forward, the header  12  cuts the grain and stalk. The header  12  moves the grain into an auger trough  14 . A transverse auger  15  pushes the grain and stalk in the auger trough  14  to the center of the header. The header  12  illustrated in FIG. 1 is a wheat or similar small grain header. The header  12  may be positioned and re-positioned relative to the ground. The header  12  may also be tilted to the left or right or may be positioned relatively high or low to the ground. These features are constantly being adjusted depending on the terrain and crop conditions. The header reel  13  may also be positioned relative to the header  12 . The position and rotation of the header reel  13 , again depends on the terrain and crop conditions. Moveable headers and header reels are well known and established in the art. Located at the center of the header is the feederhouse  21  or elevator. The feederhouse  21  moves the grain and stalks rearward into the threshing  3 , separation  4  and cleaning systems of the combine  1 . After processing and separation, the processed grain is stored in a grain tank  5  located near the top of the combine  1 . The grain is removed from the grain tank  5  by an unloading auger (not shown) through the grain tank unload tube  6 . Usually during the harvesting operations, the unloading auger remains off and the grain tank unload tube  6  remains positioned by the grain tank  5 . However, the combine can be unloaded ‘on the go’. A separate vehicle such as a truck or tractor-pulled grain cart follows the operator. The processed grain is discharged while the combine and separate vehicles are moving. After sufficient grain has been accumulated in the grain tank  5 , the operator activates the unload tube  7 . The operator  11  then positions the end of the unload tube  6  over a receptacle. Unloading augers and unload auger grain tubes are well known and established in the art. The trash or chaff is ejected from the rear of the combine by a chaff spreader  10 . The operator  11  controls the combine  1  from the cab  2  located behind the header  12  and at the front of the combine. From the cab the operator can observe most the various combine functions. The cab  2  usually has a large glass window or several windows which afford the operator the maximum ability to monitor the header  12 . The combine  1  and various systems are powered by an engine  7  generally positioned at the rear of the combine  1 . Most of the major systems in a combine are discussed and well known in the prior art. 
     The acoustic stone detector for a combine harvester feederhouse  35  may generally be observed in FIG.  1  and more specifically in FIGS. 2 through 7. As seen in FIG. 2, there is a first acoustic array  40  and second acoustic array  50  located proximate to the front drum  22  of the feederhouse  21 . These acoustic arrays  40  and  50  transmit a signal that triggers a solenoid  77 . The solenoid  77  opens a latch  75  allowing the stone trap door  60  to fall open (see FIGS.  3  and  4 ). This allows the stone  30  to drop out of the feederhouse  21 . The operator then raises the feederhouse  21  (as seen in FIG.  4 ); the door cable  62  pulls the stone trap door  60  into contact with the latch  75 . Now that the general elements of the invention have been reviewed, a more specific discussion will follow. 
     The first acoustic array  40  is located beneath the front drum  22  as seen in FIGS. 5 and 6. It consists of a first acoustic sensor  41  monitoring the first sounding plate  42 . In the preferred embodiment, the first acoustic sensor  41  is an accelerometer, Bosch™ sensor, model number 84058692. The acoustic sensor  41  could also be a microphone or similar listening device. The acoustic sensor  41  is affixed to the first sounding plate  42 . The first sounding plate  42  extends roughly parallel to the feederhouse floor  25   a . The first sounding plate  42  is positioned beneath the front drum  22  and behind an entry plate  44  extending from the header  12 . To prevent the sounding plate  42  from detecting stray sounds, the plate is insulated from the remainder of the feederhouse. Between the first sounding plate  42  and the feederhouse floor  25   a  is the first insulated plate  43 . Beneath the feederhouse floor  25   a  is the second insulated plate  46 . The sounding plate  42  is contoured to partially project beneath the entry plate  44  to further minimize the sensor  41  from receiving stray noise. A ‘U’ channel  45  supports this contoured portion of the first sounding plate  42 . Again, the ‘U’ channel is insulated with ‘U’ channel insulation  47  so as to minimize stray noise. The first acoustic sensor  42  transmits a first sensor signal through the first sensor wire  81 . A stone  30  impacting the first sounding plate  42  is detected by the first acoustic sensor  41  which sends a first signal through the first sensor wire  81 . While FIG. 5 details only one sensor  41 , it should be understood that a series of sensors might be affixed onto the first sounding plate  42  beneath the front drum  22  and entry plate  44 . 
     The second acoustic array  50  is positioned in a mounting zone  23   c . The mounting zone  23   c  is defined as the region between the upper apron  23   a  and lower apron  23   b  of the conveyor chain  23  and behind the front drum  22 . As viewed in FIGS. 5 and 6, the second acoustic array is positioned very close to the front drum  22 . The second acoustic array  50  has a second acoustic sensor  55  attached to a sounding plate or channel  51 . The second acoustic sensor  55  is identical to the first acoustic sensor  41  and is a Bosch™ accelerometer model number 84058692. It is important that the second acoustic sensor  55  be positioned close to the front drum  22  and between the upper apron  23   a  and lower apron  23   b  as possible. In the preferred embodiment, the second acoustic sensor is positioned 195.5 mm behind the center of the front drum  22 . It is also important that the second sounding plate or channel  51  not contact the front drum  22  or conveyor chain  23 . To avoid the channel  51  from receiving stray noises, there channel  51  has channel insulation  52 . As seen in FIGS. 2A and 5, the channel  51  is affixed on a pair of drum arms  27 . The drum arms  27  are pivotally attached to the sidewall  25  of the feederhouse  21  at the drum arm pivot  28 . The front drum is rotationally attached and the opposite end of each drum arm  27 . As previously mentioned, in order to prevent the channel  51  from receiving stray noise, it is important that the upper apron  23   a  and lower apron  23   b  not contact the channel  51 . In order to prevent this from occurring, a roller  53  attached by a roller support  54  to the channel  51  is utilized to keep the lower apron  23   b  from touching the channel  51 . The second acoustic sensor  55  transmits a second sensor signal through the second sensor wire  82 . As seen in FIG. 6, a stone  30  impacting the channel  51  is detected by the second acoustic sensor  55  which sends a second signal through the second sensor wire  82 . As detailed in FIG. 2A, a series of sensors may be affixed onto the channel  51 . 
     FIG. 6 illustrates a crop flow  31  containing several stones. Stones at the bottom of the crop flow  31  impact the first sounding plate  42  and that impact is detected by the first acoustic sensor  41 . Stones at the top of the crop flow  31  impact the second sounding plate or channel  51  and that impact is detected by the second acoustic sensor  55 . A single acoustic array located beneath the front drum and lacking the modified sounding plate  42  only detected 40-50 percent of stones  30  entering the feederhouse. However, the addition of the second acoustic array  50  and modified first sounding plate  42  has resulted in a 92-96 percent detection of the stones entering the feederhouse. 
     The stone trap door  60  is pivotally attached to the feederhouse floor  25   a  by a hinge  61 . When the door  60  is closed (as seen in FIG.  2 ), it seals the floor aperture  26   a . The floor aperture is an opening in the feederhouse floor  25   a . When the door  60  rotates downwards (as seen in FIG.  3 ), the floor aperture  26   a  is opened and crop material can drop to the ground. Affixed to the hinge  61  is the cable link  62  and sled link  65 . Pivotally attached to the sled link  65  is the sled linkage  71 . The sled linkage  71  has a linkage slot  72 . Located between the upper apron  23   a  and lower apron  23   b  is the stone ejection sled  70 . The ejection sled  70  is pivotally attached to the sidewall  25  by a sled hinge  73 . Affixed to the sled hinge  73  is the sled hinge link  74 . The opposite end of the sled hinge link  74  is slideably attached to the sled linkage  71  through the linkage slot  72 . 
     Receiving the first sensor signal through the first sensor wire  81  is the controller  81 . The controller  81  also receives the second sensor signal through the second sensor wire  82 . The controller  81  than transmits a solenoid signal through the solenoid wire  83  to the solenoid  77 . The controller  81  in the preferred embodiment is a New Holland® controller model number CEM 86565041. 
     The solenoid  81  is a push-type solenoid and in the preferred embodiment New Holland® solenoid model 681923 was used. The solenoid  81  receives the solenoid signal from the controller  81  through the solenoid wire  83 . Upon receiving this signal the solenoid  77  retracts a spring  76 -biased latch  75  holding the stone trap door  60  closed. As seen in FIG. 3, after the latch is retracted, the stone trap door  60  rotates downward allowing a portion of the crop flow containing a stone to exit through the door aperture  26   a . At the same time, the sled link rotates clockwise (as viewed in FIG. 3) pulling the sled linkage  71  and sled hinge link  74  downward. This rotates the sled hinge and attached stone ejection sled  70  downwards. The sled  70  contacts and deflects the lower apron  23   b  downwards. This helps to deflect the crop flow  31  containing a stone through the floor aperture  26   b . In the preferred embodiment, the stone trap door  60  rotates approximately 75 degrees and the stone ejection sled rotates approximately 25 degrees. 
     FIG. 4 illustrates how the stone trap door  60  is closed over the floor aperture  26   b . While the door  60  is open, the feederhouse is raised or rotated clockwise (as seen in FIG. 4) about the rear drum  24 . A door cable  62  attached to the cable link  62  and combine frame  28  tightens and rotates the stone door  60  counter-clockwise. The spring-biased latch  75  is inserted through a latch catch on the door  60 . This ensures that the door remains closed, those preventing any inadvertent crop loss. 
     The stone detection and ejection system operates as follows. A stone enters the header  12  and is moves with the crop flow to the feederhouse  21 . The crop flow  31  passes between the front drum and feederhouse floor  25   a . Stone  30   b  contacts the first sounding plate  42  or stone  30   a  contacts the channel or second sound plate  51 . An acoustic sensor either  41  or  55  detects the impacts and transmits a sensor signal through the sensor wire  81  or  82  to the controller  80 . The controller  80  transmits a solenoid signal through the solenoid wire  83  to the solenoid  77 . The solenoid  77  retracts the latch  75  from the latch catch  66  on the stone trap door. The stone trap door swings open allowing the portion of the crop flow containing a stone to exit the feederhouse  21  through the floor aperture  26   b . The sled link attached to the hinge  61  pulls the sled linkage  71  and sled hinge link  74  downwards. The sled hinge link  74  rotates the sled hinge  73 . The ejection sled, which is affixed to the sled hinge  73 , is rotated into contact with the lower apron  23   b . The sled  70  deflects the lower apron  23   b  and helps eject additional crop flow containing any stones. After the stone is ejected, the feederhouse is raised. A door cable  62  pulls the stone trap door  60  closed. The latch  75  is re-inserted into the latch catch  66 . 
     It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what illustrated in the drawings and described in the specification.