Automatic control systems for frost fans
OwnerGary GOTTSCHALKinventor
Life of this patent
Estimating the term…
Abstract
A retrofittable control system for controlling an engine and a clutch of a frost fan may include a data processing system, a thermostat, a human machine interface, a throttle control module, and/or a clutch control module. The control system may be configured to automatically start the fan when the thermostat detects a temperature below a user defined turn-on temperature, and to automatically shut down and park the fan when the thermostat detects a temperature above a user defined turn-off temperature. In some examples, starting up the fan may include running a clutch engagement sequence that engages the clutch at different speeds for different durations.
Claims22
A high-inertia fan system comprising:
- a fan blade assembly including a plurality of fan blades rotatably coupled to a reduction gear;
- an engine configured to spin the fan blade assembly via the reduction gear;
- a clutch assembly configured to selectively engage a drive shaft of the engine with a load shaft of the reduction gear, the clutch assembly comprising a non-centrifugal, friction clutch operable by a linear actuator driven by a direct current (DC) motor and operatively connected to the clutch;
- a thermostat configured to sense an ambient temperature;
- and
- an electronic controller in communication with the thermostat, the engine, and the clutch assembly, the controller having one or more processors and a memory, a plurality of instructions being stored in the memory and executable by the one or more processors to automatically:
- disengage the clutch in response to a first signal from the thermostat that the ambient temperature has fallen below a first threshold;
- start the engine and adjust a speed of the engine by controlling a fuel throttle of the engine;
- cause the linear actuator to actuate the clutch at a first actuation speed for a first duration, then actuate the clutch at a second actuation speed lower than the first actuation speed for a second duration, then actuate the clutch at a third actuation speed higher than the second actuation speed for a third duration, such that the fan blades are brought up to an operating speed without stalling the engine;
- run the fan blade assembly at an operating speed;
- slow the speed of the engine and disengage the clutch in response to a second signal from the thermostat that the ambient temperature has risen above a second threshold;
- and
- engage the clutch in response to stopping of the engine and the fan blade assembly, thereby preventing rotation of the fan blades.
A frost fan system for protecting crops from frost, the system comprising:
- a fan blade assembly including a plurality of fan blades rotatably coupled to a reduction gear;
- an engine configured to spin the fan blade assembly via the reduction gear;
- a clutch assembly configured to selectively engage a drive shaft of the engine with a load shaft of the reduction gear, the clutch assembly comprising a non-centrifugal, friction clutch and a manual clutch engagement mechanism;
- an environmental sensor configured to sense an environmental parameter;
- a clutch control system including a linear actuator coupled to the clutch engagement mechanism, the clutch control system further comprising an electronic controller in communication with the environmental sensor and the engine;
- wherein the electronic controller is configured to automatically:
- start the engine in response to a signal from the environmental sensor indicating that the environmental parameter has met a first threshold;
- engage the clutch by causing the linear actuator to move the clutch engagement mechanism into an engaged position;
- run the fan blade assembly at an operating speed;
- and
- slow the engine and disengage the clutch in response to a second signal from the environmental sensor that the environmental parameter has met a second threshold.
A method of retrofitting a clutch control system on a non-centrifugal clutch, the method comprising:
- coupling a motor-driven linear actuator to a manual clutch engagement mechanism of a non-centrifugal clutch of a frost fan assembly;
- placing an electronic controller in communication with an engine configured to drive the frost fan assembly and with a motor of the motor-driven linear actuator;
- and
- using the electronic controller to automatically selectively engage and disengage the clutch by controlling the motor to cause the linear actuator to position the manual clutch engagement mechanism.
Dependencies are inferred from the claim text.