Blower controller for pneumatic conveyance of granular materials

• US 8,920,078 B2
• Filed: 06/03/2010
• Issued: 12/30/2014
• Est. Priority Date: 06/03/2010
• Status: Expired due to Fees

• Current Assignee: Jason Woolever
• Original Assignee: Jason Woolever
• Inventors: Woolever, Jason A.
• Primary Examiner(s): HARP, WILLIAM RAY
• Application Number:
  US12/793,161
• Publication Number:
  US 20110299943A1
• Time in Patent Office: 1,671 Days
• Field of Search: 406/12, 406/14, 406/16
• US Class Current: 406/14
• CPC Class Codes: B65G 53/66 Use of indicator or control devices, e.g. for controlling gas pressure, for controlling proportions of material and gas, for indicating or preventing jamming of material controlling the flow of coal firing systems C21B5/003

Abstract

A system provides pneumatic conveyance of grain or other dry, loose commodities. The system conveys the commodity from a first piece of equipment, for example a grain dryer, to a second piece of equipment, for example, a grain bin. A variable speed blower motor is mounted to drive air through a transport pipe, and the blower motor speed is controlled by a processor and software providing a desired pressure to efficiently move the commodity based on the rate of discharge into the transport pipe, while minimizing wasted energy or damage to the commodity that is often experienced when more than the required pressure is provided by a blower motor. Parameters used in determining the blower motor speed may include the gauge pressure measured in the transport pipe, the rate of discharge of commodity into the transport pipe, and the blower motor current or power.

Claims

1. A pneumatic grain conveyance system for transporting grain from a grain dryer to a second piece of equipment, comprising:

at least one transport pipe having a grain inlet comprising an airlock constructed and arranged to receive grain discharged from the grain dryer, the transport pipe including a sensor;

a blower motor mounted to drive air through the at least one transport pipe;

a variable speed motor drive electrically coupled to power the blower motor; and

a processor and software operative to provide a blower motor speed control signal to the variable speed motor drive based on at least a first input corresponding to a reading from the sensor, a second input corresponding to a set point for the sensor reading, and a third input corresponding to a discharge rate of grain from the grain dryer, wherein the blower is thereby controlled to decrease the damage to the grain received from the grain dryer as the grain is transported through the transport pipe.

2. The system of claim 1, wherein the sensor comprises a pressure transducer for providing a pressure signal proportional to the pressure in the at least one transport pipe, and wherein the processor and software are operative to base the blower motor speed control signal at least in part on the magnitude of the pressure signal and a target pressure in the at least one transport pipe.

3. The system of claim 2, wherein the software includes selectable upper pressure limit and upper pressure timer limit, and the processor and software are operable to disable the blower motor and the grain dryer if the pressure signal exceeds the upper pressure limit for at least the upper time limit.

4. The system of claim 2, wherein the software includes a lower pressure limit and lower time limit, and the processor and software are operable to disable the blower motor and the first piece of equipment if the pressure signal recedes below the lower pressure limit for at least the lower time limit.

5. The system of claim 1, wherein the grain inlet includes an airlock and wherein the processor and software are operative to activate and deactivate the airlock.

6. The system of claim 5, further comprising an airlock motor associated with the airlock and at least a first switch controlled by the processor and software and operative to disable operation of the blower motor and the airlock motor.

7. The system of claim 6, further comprising at least a second switch controlled by the processor and software and connected to disable discharge of grain from the grain dryer into the at least one transport pipe.

8. The system of claim 1, wherein the processor and software determine the control signal in a feedback arrangement with respect to the first and second inputs and in a feedforward arrangement with respect to the third input.

9. The system of claim 1, further comprising a grain dryer controller, wherein the third input is received by the processor from the grain dryer controller.

10. The system of claim 9, in which the grain dryer has metering rolls and the third input corresponds to rotational speed of the metering rolls.

11. The system of claim 1, wherein the software includes a selected base speed associated with the blower motor, the base speed preventing overheating of the blower motor, and the processor and software are operative to limit the control signal based on the base speed.

12. The system of claim 1, wherein the software includes a selected starting set point, and the processor and software are operative to initially ramp up the control signal over time at least in part based on the starting set point.

13. The system of claim 1, further comprising a graphical user interface coupled to the processor and providing initiation, termination, and setting of parameters associated with the software.

14. A controller for a pneumatic grain conveyance system in which grain is conveyed in a transport pipe from a grain dryer to a second piece of equipment, the grain being driven by air pressure generated by a blower motor, the grain dryer discharge speed being controlled by a grain dryer controller, comprising:

a variable speed motor drive electrically coupled to power the blower motor;

a pressure transducer for providing a pressure signal proportional to the pressure in the transport pipe; and

a processor, the processor having an input port for receiving the pressure signal, and software adapted to enable the processor to provide a control signal to the variable speed motor drive based at least in part on the magnitude of the pressure signal and a target pressure in the at least one transport pipe;

wherein the processor includes an input port that receives a discharge speed signal from the grain dryer controller, and the processor and software are operative to determine the control signal based at least in part on the discharge speed signal, wherein the variable speed motor drive is thereby controlled to decrease the damage to the grain received from the grain dryer as the grain is transported through the transport pipe.

15. The system of claim 14, wherein the control signal may be determined by the software and processor based at least in part on a PID control model.

16. The system of claim 14, wherein the software includes a selectable upper pressure limit and an upper pressure time limit, and the processor and software are operable to disable the blower motor and the first piece of equipment if the pressure signal exceeds the selectable upper pressure limit for at least the upper pressure time limit.

17. The system of claim 14, wherein the software includes a lower pressure limit and a lower time limit, and the processor and software are operable to disable the blower motor and the first piece of equipment if the pressure signal recedes the lower pressure limit for at least the lower time limit.

18. A system for decreasing damage to dried grain during pneumatic transport from a grain dryer to a second piece of equipment, comprising:

a grain dryer for generating dried grain;

a transport pipe comprising an airlock configured to receive the dried grain and deliver it to a second piece of equipment;

a blower motor having a variable speed drive configured to drive air through the transport pipe; and

a controller operative to control the speed of the blower motor based on at least a first input corresponding to a reading from at least one sensor, a second input corresponding to a set point for the sensor reading, and a third input corresponding to the rate at which grain is entering the transport pipe to thereby decrease the damage to the dried grain as it is conveyed through the transport pipe.

19. The system of claim 18 in which the controller operates in a feedback arrangement with respect to the first and second inputs and in a feedforward arrangement with respect to the third input.

20. The system of claim 19 in which the at least one sensor is a pressure transducer and the second input is a pressure set point.