摘要:
Apparatus and a method providing a park brake for a propulsion system of an agricultural windrower having a FNR lever assembly including a FNR lever movable in relation to a neutral position in first and second directions, and a sensor for sensing positions of the FNR lever as the lever is moved and outputting signals representative thereof, the sensor being configured such that the signals outputted thereby are to have signal values within a predetermined range of values and/or which will change within a predetermined rate of change, a programmable control module in operative control of a park brake and programmed and operable for monitoring the signals and comparing the values of the signals to the predetermined range, and if the value of any of the signals is outside of the predetermined range, then automatically engaging the park brake.
摘要:
A method for calibrating a proportional solenoid valve used in the propulsion system of a windrower, wherein a programmable control module in connection with a valve and a sensor is programmed as part of an automatic calibration routine for directing test control signals to the valve for causing a predetermined displacement of the hydraulic cylinder, the test control signals having values which vary based on the actual displacement of the hydraulic cylinder as compared with a predetermined value of displacement, and operating the hydraulic cylinder using the test control signal that causes the predetermined displacement of the element. The predetermined displacements correspond to the crack points, or the electrical signal levels at which two ports of interest are just beginning to open to one another from a closed position. Of particular interest are the crack points from the supply pressure port to each of the work ports and from the tank port to each of the work ports.
摘要:
A hydrostatic system and method of operation thereof, wherein at least one of a fluid motor and a pump of the system has a displacement which is variable for controlling a speed of operation of the motor, the pump being driven by an engine, and a controller configured for monitoring the speed of operation of the motor and an operating characteristic of the engine and automatically controlling the displacement responsive thereto, wherein if the operating characteristic is indicative of engine performance above a predetermined threshold, the controller will control the displacement for maintaining the speed of operation of the motor at about a predetermined value, and, if the operating characteristic is indicative of engine performance below the threshold, the controller will hold the displacement at a constant value. As a result, the controller can prevent the system from further decreasing the engine performance. And, if the engine performance increases to that or another threshold, the controller will automatically switch back to controlling the displacement for holding the motor speed at the predetermined value, optionally including to incrementally increase the speed to the predetermined value.
摘要:
A system and method for calibrating a header flotation system of an agricultural vehicle that can be employed while the vehicle is in motion, including when traversing a field, which does not rely on, or require calibration of, height and/or pressure sensors.
摘要:
An apparatus and method for calibrating a PTO for driving a header of an agricultural windrower, wherein a programmable control module in connection with at least signal operated device in operative control of a variable displacement pump operable for controlling operation of the PTO, is programmed as part of an automatic calibration routine for determining values for the control signals required for operating the header at a predetermined target speed for a plurality or range of speeds of an engine driving the pump, such at the pump can be controlled to minimize occurrences of overpumping of fluid and resultant problems.
摘要:
The apparatus is an automatic velocity control system for an agricultural machine. Three feedback circuits are used to increase reliability and repeatability of the apparatus despite variations in load and ground conditions and non-linear responses of control components. A solenoid current sensor supplies a feedback signal to control a current controller for solenoids controlling a hydraulic valve, a hydraulic cylinder position sensor provides a feedback signal to counteract the non-linearity of the hydraulic valve controlling the hydraulic cylinder, and wheel speed sensors supply vehicle speed signals to be compared to the signal from the operator's speed control. A microprocessor processes the sensor signals to maintain the desired velocity.
摘要:
A neutral start interlock for a hydrostatic drive system that uses potentiometers to electronically monitor at least the position of the hydrostatic displacement control such that the engine will not start unless such control is in the neutral position.
摘要:
A two-channel metal detector system disposed adjacent the crop feed path of a harvester to detect ferrous metal objects in the crop material is provided with both positive and negative adaptive detection thresholds for each channel, the thresholds being independently varied according to the average positive and negative peaks of the noise component in the channel output signals. A channel output signal is sampled and digitized and the positive and negative peaks of the noise component occurring over fixed time intervals are filtered to provide average positive peak and average noise peak values that are stored in an E.sup.2 PROM and updated according to long term variations in the noise component. The positive and negative adaptive detection thresholds are set according to the average positive and negative peak values and the adaptive detection thresholds are compared with the sample channel output signal to determine if a ferrous metal object has been detected. By storing the positive and negative average peak values of the noise component in an E.sup.2 PROM memory, the adaptive detection thresholds and the filters may be initialized at system start-up to the values existing at the time of system shut-down.
摘要:
An agricultural harvesting machine having feed rolls for feeding crop material along a feed path to a cutterhead which chops the crop material is provided with a metal detector for detecting ferrous metal objects passing along the feed path. The metal detector comprises a plurality of magnets and a plurality of generally planar Hall effect sensing elements. The magnets collectively produce a detection field which extends into the crop feed path. Each sensing element is disposed such that the magnetic field produced by two adjacent magnets is normal to the plane of the sensing element. In addition the sensing elements are disposed in a plurality of planes all normal to the crop feed path. However, the sensing elements are disposed in planes oriented at different angles relative to the direction of crop feed. When a ferrous metal object passes through the detection field it varies the density of the magnetic field at one or more of the transducers and the Hall effect causes an output voltage signal to be developed across the output leads. The output signal is applied through processing circuitry to a stop apparatus to stop the feed rolls. The transducers are mounted on a circuit board and the circuit board surmounts the magnets inside a housing within one of the feed rolls. An encapsulating material fills the interior of the housing.
摘要:
In an automatic hitch control system wherein a hitch is raised or lowered in response to operation of a valve, and the valve is controlled by solenoids which are selectively energized by connecting them to ground through switch drivers, a safety disconnect relay is provided for preventing uncommanded motion of the hitch such as might occur if the lead between a solenoid and its driver should be grounded or if the driver should fail in an "on" state. The relay has contacts connected between the solenoids and the positive voltage for operating them. A microprocessor senses hitch position, the position of a quadrant lever and the speed of the tractor carrying the hitch. From the conditions sensed, the microprocessor determines if the tractor is moving, if the hitch is captured, if the hitch is moving and whether the hitch control system is in an open-loop control mode in which manual switches may be used to control hitch movement. If the hitch is not captured, or the hitch control system is in the open-loop mode, and uncommanded downward hitch motion is detected, the microprocessor energizes the safety disconnect relay to disable the hitch valve thereby preventing uncommanded downward motion of the hitch. When the hitch is captured and the control system is in a closed-loop control mode, feedback signals from the hitch act through a closed-loop to maintain the hitch at the position specified by the quadrant lever.