Abstract:
An integrated control device for an environmental system comprises a motor that is in mechanical communication with a device forcing fluid through the environmental system and a controller physically mounted to the motor. The controller includes a processor programmed to control the motor and at least one other internal system of said environmental system in response to a thermostat control signal. The other internal system may comprise a heater and/or cooling unit.

Description:
TECHNICAL FIELD  
         [0001]    This disclosure relates to environmental systems for heating, ventilation, and/or cooling an environment. More particularly, this disclosure relates to an integrated control device for such systems.  
         BACKGROUND  
         [0002]    Environmental systems, such as heating, ventilation, and air conditioning (HVAC) systems are used in many commercial and industrial applications, such as in the heating and cooling of buildings. The temperature changing capacity of an environmental system is produced by a heater and/or cooling unit. In the case of heat pumps, the cooling unit and the heater are the same system. A heater can generate heat using, for example, a combustion process, a catalytic process, a refrigeration cycle (e.g., a heat pump), an electrical resistance heating source, and others. Cooling units primarily rely on a refrigeration cycle but other cooling units are known, such as, a thermoelectric devices, evaporative coolers, environmental heat sinks, etc. The environmental system exchanges heat between a fluid, such as air, and the heater and/or cooling unit by forcing the fluid across a heat exchanger, which is in thermal communication with the heater and/or cooling unit.  
           [0003]    A blower fan can be used to force the air through the environmental system (e.g., a forced air heating and cooling system). The forced air is supplied from the heat exchanger to desired locations in the building through air passeageways or ducts.  
           [0004]    The blower fan is rotated by a blower motor. The blower motor can be a brushless DC motor that is controled by a motor controller. The motor controller comprises a microprocessor configured to operate the blower motor in a known manner. Low cost HVAC systems have a motor controller and motor that are configured to operate the blower motor at a single fixed speed. Medium cost systems have a motor controller and motor that are configured to operate the blower motor at multiple fixed speeds. Higher cost systems have a motor controller and motor that are configured to operate the blower motor at varaible speeds. These different configurations can require different components, wiring, software, and combinations of any of the foregoing.  
           [0005]    The environmental system is controlled by a system controller. The system controller recevies inputs including, for example, a control signal from a thermostat. When the system controller determines that heating is desired, the system controller sends an output signal to the heat source to generate heat and sends an output signal to the motor controller. The motor controller then activates and controls the operation of the blower motor. Similarly, when the system controller determines that cooling is desired, the system controller sends an output signal to activate the cooling source and sends an output signal to the motor controller, which activates and controls the operation of the blower motor.  
           [0006]    The required communication between the motor, the motor controller, and the system controller can add expense, complexity, and size to the HVAC system.  
         SUMMARY  
         [0007]    Disclosed herein is an integrated control device for an environmental system comprising a motor that is in mechanical communication with a device forcing fluid through the environmental system and a controller physically mounted to the motor. The controller includes a processor programmed to control the motor and at least one other internal system of said environmental system in response to a thermostat control signal. The other internal system may comprise a heater and/or cooling unit. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    The present disclosure is described, by way of example, with reference to the accompanying drawings, in which:  
         [0009]    [0009]FIG. 1 is a block diagram of an exemplary embodiment of an integrated control device;  
         [0010]    [0010]FIG. 2 is a schematic view of an exemplary embodiment of a gas furnace having an integrated control device; and  
         [0011]    [0011]FIG. 3 is a perspective view of an exemplary embodiment of the integrated control device of FIG. 2 connected in driving relation to a blower.  
     
    
     DETAILED DESCRIPTION  
       [0012]    Referring now to the Figures and in particular to FIG. 1, an integrated control device  10  for an environmental system is illustrated. Device  10  is configured to integrate an environmental system controller, a motor controller, and a blower motor into a single, simple, and inexpensive unit. Thus, device  10  can reduce the size, expense, and complexity of the environmental system.  
         [0013]    Integrated control device  10  comprises a controller  12  integrated as part of a motor  14 . Controller  12  comprises a processor  16 , a rectifier  18 , and an inverter  20 . Motor  14  is, for example, a brushless DC motor having ferrite magnets. Alternately, motor  14  may be a brushless DC motor having or rare-earth magnets (e.g., neodymium-iron-boron). Motor  14  drives a blower fan (not shown) that moves air across a heating/cooling source  22 .  
         [0014]    Device  10  is configured such that the controller  12  can receive a plurality of inputs  24  and can provide a plurality of outputs  26  to control the operation of motor  14 , source  22 , as well as other portions of the environmental system.  
         [0015]    Inputs  24  may include an input  28  of for power input (e.g., DC or 110/220 volt AC), thermostat inputs, inputs from the heat cooling source, and other inputs necessary for the control and operation of the environmental system.  
         [0016]    Outputs  26  may include a power output to a thermostat (e.g., 24 volt AC), a DC power output to motor  14 , one or more activation signals to source  22 , and other outputs necessary for the control and operation of the environmental system.  
         [0017]    Processor  16  may be a digital signal processor, microprocessor and/or other assorted electronic components well known in the field of electronic control for providing memory, input/output, and processing functions. Processor  16  is programmed to control the operation of the motor  14 .  
         [0018]    If Input  28  is 110/220 Volt AC, rectifier  18  and/or other components are configured to convert 110/220 Volt AC power to DC power. Rectifier  18  thereby provides the DC power to processor  16  and motor  14 , as well as other portions of the environmental system. In an alternative embodiment, input  28  is AC or DC power from an external transformer or other type of power supply.  
         [0019]    Inverter  20  is a switching mechanism (e.g., MOSFET type transistors) configured to selectively apply the DC voltage from the rectifier  18  to the various windings of the motor  14 . Thus, inverter  20  is coupled between the rectifier  18  and the motor  14 . The inverter is controlled by processor  16  to selectively supply the DC voltage across the motor windings to operate the motor.  
         [0020]    Accordingly, device  10  comprises controller  12  integrated into motor  14  and uses inputs  24  and outputs  26  to control the operation of the motor and source  22 . Specifically, integrated control device  10  integrates the functions of a system controller, a motor controller, and a blower motor into a single, simple, and inexpensive unit.  
         [0021]    In addition, device  10  provides the three classes of prior systems (i.e., single fixed speed systems, multiple fixed speed systems, and varaible speed systems) with only a change in software settings. This allows the same device  10  to provide all three classes of systems, which can further reduce the cost of the environmental system.  
         [0022]    Turning now to FIGS. 2 and 3, device  10  is illustrated by way of example in use with a gas furnace  30 . Gas furnace  30  comprises a gas source (not shown) feeding a plurality of burners  34  (only one shown). A solenoid operated gas valve  36  is positioned between the gas source and burners  34 . Gas valve  36  is configured to selectively supply a desired mixture of gas and air to burners  34 . Each burner  34  includes an igniter  38  adapted to selectively ignite the mixture. Device  10  is configured to provide a first output  40  to control the operation of gas valve  36  and a second output  42  to control the operation of igniters  38 .  
         [0023]    Gas furnace  30  also comprises a plurality of heat exchangers  44  in convective and/or conductive communication with the burners  34  such that the combustion of the mixture heats the heat exchangers. Supply air for the combustion process enters the gas furnace  30  and the by-products of the combustion process exit the furnace in a desired manner. For example, the by-products of the combustion process exit the furnace through an exhaust flue. In addition, an exhaust gas blower (not shown) can be configured to aid in venting the combustion by-products from gas furnace  30 .  
         [0024]    Gas furnace  30  also comprises a blower fan  46  in fluid communication with heat exchangers  44 . Blower fan  46  is configured to force a fluid, such as air, through heat exchangers  44  in the direction of arrow  48 . Specifically, motor  14  is configured to rotate a motor shaft  50 , which drives blower fan  46  through a transmission  51 . Transmission  51  may comprise a belt and pulley system, a chain and sprocket system, a gear train system, and others to drive blower fan  46 . As shown, motor  14  is directly connected to blower fan  46  by shaft  51 ; thus shaft  50  is transmission  51 .  
         [0025]    It should be recognized that gas furnace  30  is described herein by way of example as an up-flow gas furnace. Of course, other types of furnaces using heating sources other than combustion and/or furnaces that force the air in other directions through the heat exchangers are contemplated by the present disclosure.  
         [0026]    Device  10  is configured to receive a first input  52  from a thermister  54 , which is provided on the heat exchangers  44  or elsewhere in the system. Input  52  is indicative of the temperature of the air after it has been forced through heat exchangers  44 .  
         [0027]    Device  10  is also configured to provide a third output  56  and to receive a second input  58  from a thermostat  60 . Thermostat  60  may be positioned in a desired location in the building in which gas furnace  30  is installed. Thermostat  60  is a switching device that receives third output  56  from device  10 , and sends second input  58  back to the device when the thermostat detects one or more selected conditions.  
         [0028]    Third output  56  and second input  58  are, for example, control voltage signals (e.g., 24 volts AC). Thermostat  60  is configured to measure the ambient temperature in the building in which gas furnace  30  is installed. An operator adjusts a desired target temperature-using thermostat  60 . Thermostat  60  provides second input  58  to device  10  when the thermostat determines additional heat is needed to maintain the target temperature.  
         [0029]    Upon receiving second input  58 , device  10  starts gas furnace  30  to provide heat to the building. Specifically, integrated control device  10  activates motor  14  to operate blower fan  46 . Device  10  sends first output  40  to gas valve  36 , which opens the valve and provides the gas supply  32  to the burners  34 . Additionally, integrated control device  10  sends second output  42  to igniters  38  to ignite the mixture in burners  34 .  
         [0030]    Integrated control device  10  can continuously monitor first input  52  from thermister  54  while gas furnace  30  is operating. Device  10  may control the speed of the blower fan, the state of the gas valve, and/or the number of burners in operation to manage the air temperature exiting the heat exchangers  44  to a desired temperature.  
         [0031]    Thermostat  60  stops sending second input  58  to device  10  when the thermostat heat is no longer required to maintain the target temperature.  
         [0032]    Device  10  stops gas furnace  30  when second input  58  is no longer provided by thermostat  60 . Specifically, integrated control device  10  deactivates motor  14  to stop blower fan  46 . Device  10  stops sending first output  40  to the gas valve  36 , which closes the valve and shuts off gas supply  32  to burners  34 . In this example, gas valve  36  is normally biased to a closed position such that the removal of first output  40  causes the valve to open (e.g., a normally closed valve). Of course, other types of valves are contemplated for use with the present disclosure. For example, integrated control device  10  may send a second first output signal  40  to close gas valve  36  (a two-way actuated valve).  
         [0033]    Integrated control device  10  may also be configured to receive a third input  62  from an exhaust gas pressure sensor  64 . Third input  62  can be indicative of a pressure of the combustion by-products in an exhaust vent or flue. Device  10  can modify, adjust, or suppress the operation of the gas furnace based upon third input  62 . For example, integrated control device  10  can control the pressure in the exhaust vent by turning on and off or modifying the speed of an exhaust gas fan  66 , which aids in venting the combustion by-products from gas furnace  30 , by closing gas valve  36  to one or more burners  34 , and others.  
         [0034]    Accordingly, and in this manner integrated control device  10  is configured to maintain the ambient temperature in the building to a desired level. It should be recognized that the operation of gas furnace  30  by integrated control device  10  is described above by way of example only. Of course, integrated control device  10  can operate gas furnace  30  using more than, less than, and/or different inputs and outputs than those described above. For example, integrated control device  10  may receive inputs a flame sensor, a current shunt voltage resistor, and others. Device  10  may provide outputs to an exhaust fan (not shown), a humidifier (not shown), etc.  
         [0035]    Integrated control device  10  eliminates the wiring harness between the system controller and the motor controller, and between the motor controller and the motor of prior systems. Thus, the high level of integration provided by integrated control device  10  reduces the number of components, which can provide a corresponding increase in reliability.  
         [0036]    It should also be noted that the terms “first”, “second”, and “third” may be used herein to modify elements performing similar and/or analogous functions. These modifiers do not imply a spatial, sequential, or hierarchical order to the modified elements, unless otherwise indicated.  
         [0037]    While the invention has been described with reference to one or more an exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.