Tailgate sensor

Abstract

The round baler includes a frame and a tailgate pivotally mounted to the frame via a tailgate pivot axis. The tailgate is movable along a path of travel range between an open position and a closed position. When in the open position, a bale can be discharged from the baler and, when in the closed position, a bale is prevented from being discharged from the baler. The baler also includes a sensor that has a sensor axis. This sensor is mounted to the baler with the sensor axis approximately coaxial with the tailgate pivot axis. An operating portion of the sensor is operatively directly movable with the tailgate. The sensor has a mechanical rotary range that is at least the travel range of the tailgate; and an electrical sensing range. The electrical sensing range is less than both the mechanical rotary range and the travel range of the tailgate.

We claim: 
     
       1. A round baler comprising:
 a frame; 
 a tailgate including a tailgate pivot axis, the tailgate being pivotally mounted to the frame about the tailgate pivot axis, the tailgate being movable along a path of travel range between an open position and a closed position, wherein, when in the open position, a bale can be discharged from the round baler, and wherein, when in the closed position, the bale is prevented from being discharged from the round baler; and 
 a sensor having a sensor axis mounted to the baler such that the sensor axis is approximately coaxial with the tailgate pivot axis, and wherein an operating portion of the sensor is operatively connected with the tailgate, the operating portion of the sensor being configured for direct movement with the tailgate, wherein the sensor has a mechanical rotary range and an electrical sensing range, the mechanical rotary range being at least the path of travel range of the tailgate, the electrical sensing range being less than the mechanical rotary range and including only a portion of the path of travel range of the tailgate. 
 
     
     
       2. The round baler of  claim 1 , wherein the tailgate defines a path of travel angle that is defined by the open position and the closed position, the path of travel angle being greater than or equal to 90 degrees. 
     
     
       3. The round baler of  claim 2 , wherein the sensor has a sensing range defined along the path of travel of the tailgate, wherein the sensing range has a sensing angle of less than or equal to 90 degrees. 
     
     
       4. The round baler of  claim 1 , wherein the sensor has a sensing range that coincides with an upper portion of the tailgate path of travel range and does not include a lower portion of the tailgate path of travel range. 
     
     
       5. The round baler of  claim 1 , further comprising a second sensor attached to the tailgate, wherein the second sensor has a mechanical rotary range and an electrical sensing range, wherein the electrical sensing range is less that the mechanical rotary range of the second sensor and also less than the path of travel range of the tailgate, wherein the second sensor has a sensing range that includes a lower portion of the tailgate path of travel range and does not include an upper portion of the tailgate path of travel range. 
     
     
       6. The round baler of  claim 1 , wherein the sensor has a sensing range that includes a lower portion of the tailgate path of travel range and does not include an upper portion of the tailgate path of travel range. 
     
     
       7. The round baler of  claim 1 , further comprising a tailgate latch for selectively coupling the tailgate to the frame, the tailgate latch having a latched position and an unlatched position, wherein, when in the latched position, the latch secures the tailgate to the frame of the round baler when the tailgate is in the closed position, and wherein, when in the unlatched position, the tailgate is in the open position. 
     
     
       8. The round baler of  claim 7 , further comprising a position sensor in communication with the tailgate latch and a control system, wherein the position sensor communicates to the control system when the tailgate is in the latched position. 
     
     
       9. The round baler of  claim 8 , wherein the control system controls the process of closing the tailgate by:
 reducing a speed of the movement of the tailgate as the tailgate approaches the closed position; 
 increasing the speed of the movement of the tailgate as the tailgate reaches the closed position; and 
 stopping the movement of the tailgate when the position sensor communicates that the tailgate latch is in the latched position. 
 
     
     
       10. A system for controlling a tailgate comprising:
 a tailgate including a tailgate pivot, the tailgate being pivotally mounted to a frame of a round baler about the tailgate pivot, the tailgate being pivotally mounted for movement through a path of travel range defined by a closed position at a first angular position and a fully open position at a second angular position, the second angular position being spaced from the first angular position; 
 a sensor being mounted to the tailgate at the tailgate pivot, the sensor having a sensing range including only a portion of the tailgate path of travel range; 
 an actuator for moving the tailgate between the closed position and the open position; and 
 a control system in communication with the sensor, the control system having logic to control the movement of the tailgate based on a sensor measurement. 
 
     
     
       11. The system of  claim 10 , wherein the control system uses closed-loop positional feedback from the sensor when the tailgate is moved from the closed position towards the fully open position, and wherein the control system receives open-loop positional feedback from the sensor when the tailgate is moved from the open position to the closed position. 
     
     
       12. The system of  claim 10 , wherein the sensor has a mechanical rotary range and an electrical sensing range, the mechanical rotary range being at least the path of travel range of the tailgate, the electrical sensing range being less that the mechanical rotary range and also less than the path of travel range of the tailgate. 
     
     
       13. The system of  claim 12 , wherein the mechanical rotary range of the sensor is more than the tailgate path of travel range. 
     
     
       14. The system of  claim 10 , wherein the sensor has a sensing range that includes a lower portion of the tailgate path of travel range and does not include an upper portion of the tailgate path of travel range. 
     
     
       15. The system of  claim 10 , wherein the sensor has a sensing range that includes an upper portion of the tailgate path of travel range and does not include a lower portion of the tailgate path of travel range. 
     
     
       16. The system of  claim 10 , wherein the sensor measurement of the sensor is a linear change in voltage. 
     
     
       17. The system of  claim 10 , further comprising a tailgate latch for selectively coupling the tailgate to the frame of the round baler, the tailgate latch having a latched position and an unlatched position, wherein, when in the latched position, the latch secures the tailgate to the frame of the round baler when the tailgate is in the closed position, and wherein, when in the unlatched position, the tailgate is in the open position. 
     
     
       18. The system of  claim 17 , further comprising a position sensor in communication with the tailgate latch and the control system, wherein the position sensor communicates to the control system when the tailgate is in the latched position. 
     
     
       19. The system of  claim 17 , wherein the control system controls the process of closing tailgate by:
 reducing a speed of the movement of the tailgate as the tailgate approaches the closed position; 
 increasing the speed of the movement of the tailgate as the tailgate reaches the closed position; and 
 stopping the movement of the tailgate when the latch sensor communicates that the tailgate is in a latched position. 
 
     
     
       20. A baler comprising:
 a frame and a tailgate for allowing bales to be discharged from the baler, the tailgate being adapted to pivot about a tailgate pivot axis relative to the frame, the tailgate being able to pivot through a tailgate range of pivotal movement; 
 a rotary sensor including a sensor housing and a sensor rotary member, the sensor rotary member being mounted within the sensor housing, the sensor housing and the sensor rotary member being rotatable relative to one another about a sensor axis of rotation, the rotary sensor having a mechanical range of rotary movement between the sensor housing and the sensor rotary member, the rotary sensor having a sensed range of rotary movement between the sensor housing and the sensor rotary member, the mechanical range of rotary movement being greater than the sensed range of rotary movement, the mechanical range of rotary movement being equal to or greater than the tailgate range of pivotal movement, and the sensed range of rotary movement including only a portion of the tailgate range of pivotal movement; and 
 the rotary sensor being mounted with the sensor axis of rotation generally coaxially aligned with the tailgate pivot axis, the sensor housing being coupled to one of the frame and the tailgate and the sensor rotary member being coupled to the other of the frame and the tailgate, the rotary sensor being mounted such that the rotary sensor and the tailgate rotate together at a one-to-one ratio as the tailgate moves through the tailgate range of pivotal movement, the rotary sensor mechanically rotating with the tailgate throughout the entire tailgate range of pivotal movement. 
 
     
     
       21. The baler of  claim 20 , wherein the sensed range includes an upper portion of the tailgate path of travel range and does not include a lower portion of the tailgate path of travel range. 
     
     
       22. The baler of  claim 20 , wherein the mechanical rotary range of the sensor is more than the path of travel range of the tailgate. 
     
     
       23. The baler of  claim 20 , wherein the tailgate is movable along the tailgate range between an open position and a closed position, the baler further comprising:
 a tailgate latch for selectively coupling the tailgate to the frame of the baler, the tailgate latch having a latched position and an unlatched position, wherein, when in the latched position, the latch secures the tailgate to the frame of the baler when the tailgate is in the closed position, and wherein, when in the unlatched position, the tailgate is in the open position; and 
 an actuator for moving the tailgate between the closed position and the open position; 
 a control system in communication with the rotary sensor, the control system having logic to control movement of the tailgate based on a rotary sensor measurement; 
 a position sensor in communication with the tailgate latch and the control system, wherein the position sensor communicates to the control system when the tailgate is in the latched position, 
 wherein the control system controls the process of closing the tailgate by:
 reducing a speed of the movement of the actuator as the tailgate approaches the closed position; 
 increasing the speed of the movement of the actuator as the tailgate reaches the closed position; and 
 stopping the movement of the tailgate when the position sensor communicates that the latch is in the latched position. 
 
 
     
     
       24. A system for controlling a tailgate comprising:
 a tailgate including a tailgate pivot, the tailgate being pivotally mounted to a frame of a round baler about the tailgate pivot, the tailgate being pivotally mounted for movement through a path of travel range defined by a closed position at a first angular position and a fully open position at a second angular position, the second angular position being spaced from the first angular position; 
 a tailgate sensor being mounted to the tailgate at the tailgate pivot; 
 a tailgate latch for selectively coupling the tailgate to the frame of the round baler, the tailgate latch having a latched position and an unlatched position, wherein, when in the latched position, the latch secures the tailgate to the frame of the round baler when the tailgate is in the closed position, and wherein, when in the unlatched position, the tailgate is in the open position; 
 an actuator for moving the tailgate between the closed position and the open position and for moving the tailgate latch between the latched position and the unlatched position; 
 a control system in communication with the tailgate sensor, the control system having logic to control the movement of the tailgate based on a sensor measurement; and 
 a latch sensor in communication with the tailgate latch and the control system, wherein the latch sensor communicates to the control system when the tailgate is in the latched position, 
 wherein the control system controls the process of closing the tailgate by:
 reducing a speed of the movement of the actuator as the tailgate approaches the closed position; 
 increasing the speed of the movement of the actuator as the tailgate reaches the closed position; and 
 stopping the movement of the tailgate when the latch sensor communicates that the latch is in the latched position. 
 
 
     
     
       25. The system of  claim 24 , wherein the tailgate sensor senses movement along a portion of the tailgate path of travel between the open position and the closed position. 
     
     
       26. The system of  claim 24 , wherein the tailgate sensor has a sensing range of less than the tailgate path of travel range. 
     
     
       27. The system of  claim 24 , wherein the latch sensor is at least one of a proximity sensor and a contact sensor. 
     
     
       28. The system of  claim 24 , wherein the control system uses closed-loop positional feedback from the sensor when the tailgate is moved from the closed position towards the fully open position, and wherein the control system receives open-loop positional feedback from the sensor when the tailgate is moved from the open position to the closed position.