Patent Publication Number: US-2019195559-A1

Title: Grain Bin Dryer Pressure Control System

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not applicable to this application. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable to this application. 
     BACKGROUND 
     Field 
     Example embodiments in general relate to a grain bin dryer pressure control system for reducing the risk of excessive pressure within a grain bin. 
     Related Art 
     Any discussion of the related art throughout the specification should in no way be considered as an admission that such related art is widely known or forms part of common general knowledge in the field. 
     After grain is harvested, it is stored in a grain bin prior to sale.  FIG. 1  illustrates a typical prior art cylindrical grain bin  10  filled with grain  12 . The bin  10  includes sidewalls  14  with a door  16  for access to the interior, a roof  18  with one or more exhaust vents  20 , a bottom  22 , and a floor  24  with slots  26 . The space between the bottom  22  and the floor  24  defines a plenum  28 . 
     In order to remove moisture from the grain and prevent it from molding, one or more dryer fans  30  are used to force air through the plenum  28  and the slots  26 . The air circulates through the grain  12  and exits the bin  10  through the vents  20 , as indicated by the arrows, carrying with it moisture removed from the grain. Heaters (not shown) may be used in conjunction with the fans  30  to speed the drying. 
     In certain situations, the exhaust vents  20  in the roof  18  may become partially or completely obstructed. For example, in very cold weather the moisture removed from the grain  12  may condense in or around the exhaust vents  20  and freeze. Grain dust, fines, or other debris may also block the vents  20 . With the exhaust route obstructed, pressure may build up in the bin  10  when the drying fans  30  are running. Given enough time, the pressure may increase to such an extent that the roof  10  bulges outward (see  FIG. 2 ) and, in extreme circumstances, separate from the bin  10  causing extensive damage that is costly and time consuming to repair. 
     SUMMARY 
     An example embodiment of the present invention is directed to a grain bin dryer pressure control system. The grain bin dryer pressure control system generally includes a static pressure sensor mounted inside a grain bin and a controller. The controller includes an input coupled to receive a signal from the pressure sensor indicative of a static pressure inside the grain bin. The controller also includes a first output operable to shut off power to a drying fan when the static pressure inside the grain bin exceeds a predetermined value. 
     There has thus been outlined, rather broadly, some of the features of the grain bin dryer pressure control system in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the grain bin dryer pressure control system that will be described hereinafter and that will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment of the grain bin dryer pressure control system in detail, it is to be understood that the grain bin dryer pressure control system is not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. The grain bin dryer pressure control system is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Example embodiments will become more fully understood from the detailed description given herein below and the accompanying drawings, wherein like elements are represented by like reference characters, which are given by way of illustration only and thus are not limitative of the example embodiments herein. 
         FIG. 1  is a schematic side view of a prior art grain bin. 
         FIG. 2  is a schematic side view of a prior art grain bin experiencing an overpressure event. 
         FIG. 3 a    is a block diagram of the grain bin dryer pressure control system in accordance with an example embodiment, including a first configuration of a switch to shut off power to dryer fans. 
         FIG. 3 b    is a block diagram of a second configuration a switch to shut off power to dryer fans of an example embodiment. 
         FIG. 4  is a schematic side view of the grain bin dryer pressure control system of  FIG. 3 a    installed in a grain bin. 
         FIG. 5  is an upper perspective partial cutaway view of a grain bin with an example embodiment. 
         FIG. 6  illustrates alternative locations for the installation of the grain bin dryer pressure control system of  FIG. 3   a.    
         FIG. 7  is a block diagram of the grain bin dryer pressure control system in accordance with another example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     An example grain bin dryer pressure control system generally comprises a static pressure sensor and a controller operable to turn off dryer fans if the pressure inside the bin exceeds a predetermined level. 
     As illustrated in the block diagram of  FIG. 3 a   , an example grain bin dryer pressure control system  100  generally comprises a static pressure sensor  102  and a controller  104 . The controller  104  includes an input interface  106 , configured to receive signals from the sensor  102 , and an output interface  108  coupled to control power to one or more dryer fans  30 . As illustrated in  FIG. 4 , the sensor  102  is preferably installed on the underside of the roof  18  of a grain bin  10 , above the level of the grain  12 . In this location (location ‘A’), the sensor may accurately measure the static pressure of the air within the bin  10 . However,  FIG. 5  illustrates other locations where the sensor  102  may also be installed, such as above the level of the grain on the inside of the sidewall  14  (location ‘B’), below the level of the grain on the inside of the sidewall  14  (location ‘C’), or on the inside of the sidewall  14  near the door  16  (location ‘D’). The controller  104  may be co-located with the sensor  102  or may be installed in convenient location, such as on the outside of the sidewall  14  near the door  16 . 
     As illustrated in  FIG. 3 a   , the output  108  may be operable to control a switch  34  electrically coupled between the dryer fans  30  and a power source  32  such that power to the fans  30  may be turned off by the controller  104 . Alternatively, as illustrated in  FIG. 3 b   , the output  108  may control a switch  36  within the fans  30 , electrically coupled between the fans  30  and the power source  32 , to turn the fans  30  off at the direction of the controller  104 . 
     The controller  104  may also include an additional output  110  operatively coupled to an audible warning device  112 , a visual warning device  114 , or both. When shutting off the fans  30 , the controller  104  may activate the audible warning device  112 , such as a buzzer, bell, or siren, the visual warning device  114 , such as a flashing light, or both, to alert workers of the problem. 
     The controller may also include its own a display  116  presenting the current static pressure inside the bin  10  to be viewed by a worker. The display  116  may also present past values of the static pressure, as a list or in graphical format for detecting any problematic trends. 
     To install the system  100 , the sensor  102  is secured to the inside of the bin  10  at a location where it is able to accurately measure the static pressure of the air inside the bin  10 , such as location ‘A,’ for example. If the controller  104  is not co-located with the sensor  102 , the controller  104  is secured to a location where it is convenient for a user to make adjustments and monitor its operation. The sensor  102  is operatively coupled to the input  106  of the controller  104 , such as with wire ( FIG. 3 a   ). 
     When the system  100  is installed, the controller  104  is adjusted to respond to a signal from the sensor  102  indicating that the pressure inside the bin  10  has reached a predetermined set point above which there is a risk of structural failure in the bin  10 . For example, the predetermined set point could be, but is not limited to, about 0.75 inches of static pressure. However, the predetermined set point pressure may be greater than or less than 0.75 inches of static pressure based on various factors including the type of grain bin, typical expected weather conditions and the like. In use, the sensor  102  measures the static pressure inside the bin  10  and transmits the pressure signal to the controller  104 . The controller  104  compares the value indicated by the received signal against the setpoint. As long as the indicated pressure is less than the setpoint, no action is taken. However, if the indicated pressure exceeds the setpoint, the controller  104 , through the output  108 , commands the switch  34  to shut off power to the fans  30 , preventing further build-up of pressure and damage to the bin  10 . 
     While  FIG. 3 a    illustrates wired connections between the controller  104  and the sensor  102 , switch  34 , and warning devices  112 ,  114 , the controller  104  may also include a network interface  118  to a network  40  ( FIG. 6 ). The network  40  may be a wired or wireless local network and the interface  118  a wired or wireless interface. The network  40  may be a WiFi network or may include Bluetooth® communication. The network  40  may also be a cellular network and the interface  116  a cellular interface. The controller  104  may communicate with any or all of the sensor  102 , switch  34 , and alarms  112 ,  114  through the network  40 . Thus, the sensor  102  may transmit the pressure signal to the controller  104  through the network interface  118  and the input  106 . The controller  104  may direct that the switch  34 ,  36  shut off power to the fans  30  through the output  120  and the network interface  118 . The controller  104  may also activate the warning devices  112 ,  114  through the output  120  and the network interface  118 . 
     When the controller  104  shuts off the fans  30 , it may also transmit a signal from the output  120  through the network interface  118  and the network  40  to a remote device  50 . The remote device  50  may be any type of portable or fixed electronic device, such as a conventional cell phone, a smart phone, a tablet computer, a desktop computer, or a device dedicated to receiving signals from the controller  104 . When the remote device  50  is a portable device, the worker is able to receive the signal from the controller  104  anywhere, whether on-site or not. 
     Although the network  40  is illustrated in  FIG. 6  as being a single network, the system  100  be implemented with more than one network or type of network. By way of example only, the system may include Bluetooth communications between the sensor  102  and the controller  104 , a local WiFi network between the controller  104  and the alarms  112 ,  114 , and a cellular network between the controller  104  and the remote device  50 . 
     The signal from the controller  104  to the remote device  50  may be a simple alert that the fans  30  were shut off or a more detailed message, such as by text or e-mail, that includes the time the fans  30  were shut off and the static pressure inside the bin  10 . The controller  104  may also be configured to transmit a continuous or periodic signal containing a real-time indication of the static pressure within the bin  10 . In this way, a worker may take note of any trends that indicate that the pressure is increasing because the exhaust vents  20  are becoming blocked. The worker may then take preventive steps, such as clearing the exhaust vents  20 . If the remote device  50  has an appropriate display, the pressure values may be presented on the remote device  50  as a numerical list or in a graphical format for detection of trends in the pressure. 
     The controller  104  may also be configured to receive a signal from the remote device  50  through the network  40  and network interface  118 . The received signal may comprise a command initiated by a worker to shut off power to the fans  30 . For example, based on signals received on the remote device  50  from the controller  102 , the worker may have noticed a trend of increasing pressure inside the bin  10  and want to turn off the fans  30  before the setpoint value is reached. That provides the worker with time to investigate and resolve the problem without the pressure increasing any further. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the grain bin dryer pressure control system, suitable methods and materials are described above. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety to the extent allowed by applicable law and regulations. The grain bin dryer pressure control system may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive. Any headings utilized within the description are for convenience only and have no legal or limiting effect.