Combine speed control
First Claim
1. In a vehicle driven by an internal combustion engine, the combination ofmeans including first and second transducers for deriving speed and load signals which are functions respectively of the ground speed of said vehicle and the load on said engine,comparator means for generating speed error and load error values which are functions respectively of the differences between said speed and load signals and preset speed and load values,means for establishing speed error and load error deadbands having upper and lower limits on opposite sides of said preset speed and preset load values respectively,OR-means for identifying a single dominant controlling signal representing the limiting capacity in the vehicle as conditions change during operation thereof and for generating a speed decrease command in response to said dominant signal when a positive error value of one of said error values is beyond the upper limit of its deadband,AND-means for generating a speed increase command when a negative speed error value and a negative load error value are beyond the lower limits of said deadbands,error summing means for generating a rate-of-response value which is a function of the magnitudes of said speed error and load error values,means for modulating said speed decrease and said speed increase commands as a function of said rate of response value, andmeans for decreasing and for increasing the ground speed of said vehicle respectively in response to the modulated speed decrease and modulated speed increase commands.
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Accused Products
Abstract
A ground speed control for an agricultural combine driven by a turbocharged engine through a variable transmission continuously monitors a plurality of speed and load parameters of the combine and engine, identifies the controlling parameter representing the limiting capacity in the harvesting process as field conditions change, and varies combine ground speed in response to such controlling parameter to maximize the harvest cutting rate. Sensors monitor ground speed, boost pressure and engine speed parameters and convert them to electrical signals which are compared to boost pressure and ground speed setpoint signals selected by the operator and to a fixed engine speed setpoint signal to derive error signals for such parameters. Voltage level sensitive OR-means and AND-means establish deadbands for the error signals having upper and lower limits on opposite sides of the corresponding setpoint signals. The OR-means generates a speed decrease signal to decrease the transmission drive ratio and slow down the combine when any positive error signal is beyond its upper deadband limit. The AND-means generates a speed increase signal to increase the transmission drive ratio when both boost pressure and ground speed negative error signals are beyond their lower deadband limits. The speed increase and speed decrease signals are modulated by a rate of response signal which is a function of the magnitude of the parameter error signals so that the control both identifies and responds to the controlling parameter which has the greatest error and also responds at a rate which is a function of the magnitude of such error.
60 Citations
26 Claims
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1. In a vehicle driven by an internal combustion engine, the combination of
means including first and second transducers for deriving speed and load signals which are functions respectively of the ground speed of said vehicle and the load on said engine, comparator means for generating speed error and load error values which are functions respectively of the differences between said speed and load signals and preset speed and load values, means for establishing speed error and load error deadbands having upper and lower limits on opposite sides of said preset speed and preset load values respectively, OR-means for identifying a single dominant controlling signal representing the limiting capacity in the vehicle as conditions change during operation thereof and for generating a speed decrease command in response to said dominant signal when a positive error value of one of said error values is beyond the upper limit of its deadband, AND-means for generating a speed increase command when a negative speed error value and a negative load error value are beyond the lower limits of said deadbands, error summing means for generating a rate-of-response value which is a function of the magnitudes of said speed error and load error values, means for modulating said speed decrease and said speed increase commands as a function of said rate of response value, and means for decreasing and for increasing the ground speed of said vehicle respectively in response to the modulated speed decrease and modulated speed increase commands.
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8. In an agricultural combine vehicle driven by an internal combustion engine through a variable transmission, the combination of
means including first and second transducers for generating speed and load signals which are functions respectively of the ground speed of said vehicle and the load on said engine, speed setpoint and load setpoint potentiometer means on said vehicle adjustable by the vehicle operator for deriving setpoint signals indicative of desired vehicle ground speed and desired load on said engine, first and second adder means for deriving speed error and load error signals which are functions respectively of the differences between said speed and load signals and the corresponding setpoint signals, first comparator means receiving said speed error signal as an input for establishing a deadband for said speed error signal having upper and lower limits on opposite sides of said speed setpoint signal, second comparator means receiving said load error signal as an input for establishing a deadband for said load error signal having upper and lower limits on opposite sides of said load setpoint signal, OR-means for identifying a single dominant controlling signal representing the limiting capacity in the vehicle as conditions change during operation thereof and for deriving a speed decrease signal in response to said dominant signal when a positive error signal of one of said error signals is beyond the upper limit of its deadband, AND-means for deriving a speed increase signal when a negative speed error signal and a negative load error signal are beyond the lower limits of their deadbands, error summing means for generating a rate-of-response signal which is a function of the magnitudes of said speed error signal and said load error signal, means for modulating said speed decrease signal and said speed increase signal as a function of said rate-of-response signal, and means for decreasing and for increasing the drive ratio of said transmission respectively in response to the modulated speed decrease signal and the modulated speed increase signal.
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16. In an agricultural combine driven by an internal combustion engine, in combination,
means including first and second transducers for deriving a speed signal and a load signal respectively which are functions of the ground speed of said combine and the load on said engine, setpoint establishing means adjustable by the combine operator for generating speed and load setpoint signals which respectively are indicative of desired ground speed of said combine and desired load on said engine, comparator means for deriving speed error and load error signals which are respectively functions of the differences between said speed and load signals and the corresponding setpoint signals, OR-means for identifying a single dominant controlling signal representing the limiting capacity in the combine as condition change during operation thereof and for generating a speed decrease signal in response to said dominant signal when a positive error signal of one of said signals exceeds its predetermined magnitude, AND-means for generating a speed increase signal when a negative speed error signal exceeds its said predetermined magnitude and a negative load error signal exceeds its said predetermined magnitude; -
error summing means for generating a rate-of-response signal which is a function of the magnitudes of said speed error signal and said load error signal, means for modulating said speed decrease signal and said speed increase signal as a function of said rate-of-response signal, and means for decreasing and for increasing the ground speed of said combine respectively in response to the modulated speed decrease signal and the modulated speed increase signal. - View Dependent Claims (17, 18, 19, 21, 22)
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23. In a vehicle driven by an internal combustion engine, the combination of
a plurality of transducers for generating speed and load signals which respectively are functions of speed and load parameters of said engine, means for deriving setpoint values indicative of desired values for said parameters, comparator means for generating error values which are functions of the differences between said speed and load values and the corresponding setpoint values, OR-means for identifying a single dominant controlling signal representing the limiting capacity in the vehicle as conditions change during operation thereof and for generating a speed decrease command in response to said dominant signal when a positive one of said error values exceeds a predetermined magnitude, AND-means for generating a speed increase command when a plurality of negative error values exceed predetermined magnitudes, means for deriving a rate-of-response value which is a function of the magnitudes of said error values, means for modulating said speed decrease and speed increase commands as a function of said rate-of-response value, and means for decreasing and for increasing the ground speed of said vehicle respectively in response to the modulated speed decrease and modulated speed increase commands.
Specification