Patent Publication Number: US-2020300255-A1

Title: Fan System with Control Cooling and Method

Description:
CLAIM OF PRIORITY 
     This application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 62/819,730, filed on Mar. 18, 2019, which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     Embodiments described herein generally relate to fans having electronic control circuitry and methods. 
     BACKGROUND 
     Industrial fans for HVAC, venting, or other uses typically utilize a local electronic module to control one or more motor function. It is desired to provide fan assembly configurations that provide high efficiency and reliability to the assemblies. In one example, specifically improving efficiency and reducing stress on the electronic module is desired. Improved fan assembly configurations and methods are desired that address these concerns, and other technical challenges. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  shows a fan assembly in accordance with some example embodiments. 
         FIG. 1B  shows another fan assembly in accordance with some example embodiments. 
         FIG. 1C  shows another fan assembly in accordance with some example embodiments. 
         FIG. 2  shows a heat exchanger in accordance with some example embodiments. 
         FIG. 3  shows a heat exchanger in accordance with some example embodiments. 
         FIG. 4  shows another fan assembly in accordance with some example embodiments. 
         FIG. 5  shows a flow diagram of a method of operation of a fan assembly in accordance with some example embodiments. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims. 
       FIG. 1A  shows an example fan assembly  100 . The fan assembly  100  includes a fan housing  102  that defines an airflow pathway  104 . In operation, airflow is indicated by arrows within the airflow pathway  104 . Inlet airflow  106  and outlet airflow  108  are both indicated within the airflow pathway  104 . 
     An impeller  110  is further illustrated in  FIG. 1A , located within the airflow pathway  104 . In the example of  FIGS. 1A-1C , an axial flow impeller is shown, although he invention is not so limited. Other impeller types, including, but not limited to, radial flow impellers, or mixed axial and radial flow impellers are also within the scope of the invention. 
     The impeller  110  is coupled to a shaft  114  of an electric motor  112 .  FIG. 1A  further shows a motor controller  116  that is mounted outside the airflow pathway  104 . In one example, the motor is an electronically commutated (EC) motor that is controlled by the motor controller  116 . Although an EC motor is used as an example, other electric motors are within the scope of the invention.  FIG. 1A  shows the motor controller  116  coupled to the electric motor  112  through connecting wires  118 . Connecting wires  118  may provide both power and control information to the electric motor  112 . In the example shown, the connecting wires  118  are housed within an electrical connection conduit  120 . 
     In one example, the motor controller  116  is located partially or completely outside the airflow pathway  104  to facilitate easier electrical connection to an external power source (not shown). In one example, the motor controller  116  is located partially or completely outside the airflow pathway  104  to reduce bulky circuitry that may impede air flow. In one example, motor controller  116  is located partially or completely outside the airflow pathway  104  to improve access for maintenance or service to the motor controller  116 . 
       FIG. 1A  further shows a heat exchanger  122  located at least partially within the airflow pathway  104  and coupled between the airflow pathway  104  and the motor controller  116 . In operation, the motor controller  116  may generate significant heat. By providing increased cooling to the motor controller  116 , improved efficiency of the motor controller  116  and/or increased output of the controller  116  will be realized. In addition, by removing the motor controller  116  from the airflow pathway  104 , the electric motor  112  is in direct contact with a larger portion of the airflow  106 ,  108 . The additional exposure of the electric motor  112  to the airflow  106 ,  108  provides improved motor cooling, which further improves performance of the fan system  100  as a whole. 
     In the example of  FIG. 1A , the heat exchanger  122  is incorporated at least partially into the electrical connection conduit  120 . By incorporating the heat exchanger  122  into existing structures within the airflow pathway  104 , a number of obstructions to airflow is reduced. 
       FIG. 1B  shows another example of a fan assembly  130  according to an embodiment of the invention. In  FIG. 1B , the heat exchanger  122  is located separately within the airflow pathway  104 . In one example, by locating the heat exchanger  122  by itself, apart from other structures within the airflow pathway  104 , an amount of surface area of the heat exchanger  122  exposed to airflow is increased, and cooling efficiency will be higher. 
       FIG. 1C  shows another example of a fan assembly  160  according to an embodiment of the invention. In  FIG. 1C , the heat exchanger  122  is incorporated into an electric motor support structure  162 . Similar to integration of the heat exchanger  122  within the electrical connection conduit  120 , the incorporation of the heat exchanger  122  at least partially within the electric motor support structure  162  reduces the number of components within the airflow pathway  104  that may reduce airflow. In the example of  FIG. 1C , a lateral heat transfer connection  124  is shown to couple the heat exchanger  122  to the motor controller  116 . 
       FIGS. 1A-1C  show the heat exchanger  122  extending towards the electric motor  112  to an intermediate distance. In other examples, the heat exchanger  122  may extend the full distance to the electric motor  112 , or to a lesser distance, provided some active portion of the heat exchanger  122  is at least partially within the airflow pathway  104 . In operation, the portion of the heat exchanger  122  within the airflow pathway  104  exchanges heat drawn from the electric motor  112  with the airflow  106 ,  108  to cool the motor controller  116 . 
     In one example, the heat exchanger  122  is located within the inlet airflow  106 . In one example, the heat exchanger  122  is located within the outlet airflow  108 . In the examples of  FIG. 1A-1C , the heat exchanger  122  is located proximate to the motor controller  116  to make the heat transfer path relatively short. Although a single heat exchanger  122  is shown, multiple heat exchangers may be used. In one example, heat exchangers are located in both the inlet airflow  106  and the outlet airflow  108 . Multiple heat exchangers may increase a rate of cooling and/or a cooling amount. 
       FIG. 2  shows one example of a heat exchanger  200  that may be similar to heat exchanger  122  from  FIGS. 1A-1C . In the example of  FIG. 2 , the heat exchanger  200  includes a cooling medium configured to circulate between a motor controller as shown in previous figures, and other active portions of the heat exchanger  200 . A channel  210  is shown with arrows  212  indicating flow of a cooling media. In one example, the cooling media includes a liquid. In one example, the cooling media includes a gas. In one example, the cooling media is circulated through the channel  210  with a pump (not shown). 
     The heat exchanger  200  of  FIG. 2  shows a first region  202  and a second region  204 , with the channel  210  located to circulate the cooling media between the first region  202  and the second region  204 . In one example, the first region  202  is thermally coupled to a motor controller as shown in  FIG. 1A-1C . In one example, the second region  204  is located at least partially within an airflow pathway such as airflow pathway  104 . An intermediate region  206  may be included separating the first region  202  from the second region  204 . In one example, the intermediate region  206  may be located by a fan housing such as fan housing  102 . 
     In one example, one or more of the regions  202 ,  204 ,  206  are formed from heat conducting materials, such as metal or metal alloy. Other heat conducting materials may include carbon or carbon fiber composites. In one example, the second region  204  includes one or more fins  220 . The inclusion of fins on the second region  204  increases a surface area of the second region  204 , and provides increased heat transfer from the second region  204 . Fins may be integrally formed into the second region  204 , or may be attached in contact with the second region  204  to provide a thermal pathway. In one example, the fins  220  are oriented parallel to an airflow pathway to improve laminar airflow while providing a heat transfer function. In one example, the fins  220  are oriented vertically. Other orientations of fins  220  are also within the scope of the invention. Other surface area increasing features are also within the scope of the invention. For example, dimples or protrusions of any shape may be added to the second region  204  to increase heat transfer ability. 
       FIG. 3  shows one example of a heat exchanger  300  that may be similar to heat exchanger  122  from  FIGS. 1A-1C . In the example of  FIG. 3 , the heat exchanger  300  does not include an active system such as the circulating cooling media of heat exchanger  200 . The example heat exchanger  300  is a passive heat exchanger, wherein heat is conducted through heat conducting materials such as metal, metal alloys, carbon, composites, etc. The heat exchanger  300  shows a first region  302  and a second region  304 . Similar to the heat exchanger  200  of  FIG. 2 , in one example, the first region  302  is thermally coupled to a motor controller as shown in  FIG. 1A-1C . In one example, the second region  304  is located at least partially within an airflow pathway such as airflow pathway  104 . 
     In one example heat exchanger  300  includes one or more fins  310  separated from one another by spaces  312 , located on the second region  304 . Similar to the example of  FIG. 2 , the inclusion of fins  310  on the second region  304  increases a surface area of the second region  304 , and provides increased heat transfer from the second region  304 . Fins may be integrally formed, or may be attached in contact with the second region  304 . Ion one example, the fins  310  are oriented parallel to an airflow pathway to improve laminar airflow while providing a heat transfer function. Other orientations of fins  310  are also within the scope of the invention. Other surface area increasing features are also within the scope of the invention. 
       FIG. 4  shows another fan assembly  400  that may incorporate a heat exchanger as described in the above examples. The fan assembly  400  includes a fan housing  402  and an impeller  410 . In the example of  FIG. 4 , the impeller  410  is a centrifugal impeller. A motor  410  and a motor controller  416  are shown coupled to the impeller  410 . In one example, the motor controller  416  is located outside of an airflow pathway. In selected examples, the motor  410  may also be located outside the airflow pathway. A heat exchanger  422  is shown in block diagram form coupled to the motor controller  416 , and located at least partially within an airflow pathway. For ease of illustration, the airflow pathway is shown without additional walls or other containment to define the airflow pathway. In the example of  FIG. 4 , the unillustrated containment structure, such as a wall, will be located to separate at least the motor controller  422  from the airflow pathway. The example of  FIG. 4 , illustrates that a heat exchanger may be coupled between a motor controller and an airflow pathway in a number of different fan types, and that the invention is not limited to axial fan assemblies. 
       FIG. 5  shows a flow diagram of a method of operating a fan assembly. In operation  502 , an electric motor is controlled within an airflow pathway of a fan housing using a motor controller. The motor controller is located outside or at least partially outside the airflow pathway. In operation  504 , an impeller is rotated within the airflow pathway, where the impeller is driven by the electric motor. In operation  506 , heat is drawn from the motor controller through a heat exchanger coupled to the motor controller, and the heat is transferred to air flowing within the airflow pathway using the heat exchanger. 
     To better illustrate the fans and methods disclosed herein, a non-limiting list of embodiments is provided here: 
     Example 1 includes a fan assembly. The fan assembly includes a fan housing, defining an airflow pathway, an impeller located within the airflow pathway of the fan housing, wherein the impeller is coupled to a shaft of an electric motor, a motor controller mounted outside the airflow pathway, the motor controller electrically coupled to the electric motor, and a heat exchanger located at least partially within the airflow pathway, and coupled between the airflow pathway and the motor controller, wherein the heat exchanger is configured to move heat from the motor controller to the airflow pathway when the fan assembly is in operation. 
     Example 2 includes the fan assembly of example 1, wherein the heat exchanger includes one or more cooling fins. 
     Example 3 includes the fan assembly of any one of examples 1-2, wherein the heat exchanger includes a cooling medium configured to circulate between the motor controller and the heat exchanger. 
     Example 4 includes the fan assembly of any one of examples 1-3, wherein the cooling medium includes a liquid cooling medium. 
     Example 5 includes the fan assembly of any one of examples 1-4, wherein the impeller is an axial flow impeller. 
     Example 6 includes the fan assembly of any one of examples 1-5, wherein the impeller is a radial flow impeller. 
     Example 7 includes the fan assembly of any one of examples 1-6, wherein the heat exchanger is incorporated into an electric motor support structure. 
     Example 8 includes the fan assembly of any one of examples 1-7, wherein the heat exchanger is incorporated into an electrical connection conduit. 
     Example 9 includes a fan assembly. The fan assembly includes a fan housing, defining an airflow pathway, an electric motor located within the fan housing, an impeller coupled to a shaft of the electric motor, a motor controller mounted outside the airflow pathway, and one or more metal fins located at least partially within the airflow pathway, and physically contacting the motor controller, wherein the one or more metal fins are configured to move heat from the motor controller to the airflow pathway when the fan assembly is in operation. 
     Example 10 includes the fan assembly of example 9, wherein the impeller is an axial flow impeller. 
     Example 11 includes the fan assembly of any one of examples 9-10, wherein the impeller is a radial flow impeller. 
     Example 12 includes the fan assembly of any one of examples 9-11, wherein the one or more metal fins are incorporated into an electric motor support structure. 
     Example 13 includes the fan assembly of any one of examples 9-12, wherein the one or more metal fins are incorporated into an electrical connection conduit between the electric motor and the motor controller. 
     Example 14 includes a method of cooling, including controlling an electric motor within an airflow pathway of a fan housing using a motor controller, wherein the motor controller is located outside the airflow pathway, rotating an impeller driven by the electric motor within the airflow pathway, and drawing heat from the motor controller through a heat exchanger coupled to the motor controller, and transferring the heat to air flowing within the airflow pathway using the heat exchanger. 
     Example 15 includes the method of example 14, wherein drawing heat from the motor controller through a heat exchanger includes transferring heat to a cooling medium and circulating the cooling medium through the airflow pathway. 
     Example 16 includes the method of any one of examples 14-15, wherein drawing heat from the motor controller through a heat exchanger includes conducting heat from the motor controller into one or more metallic fins, wherein the one or more metallic fins are located within the airflow pathway. 
     Example 17 includes the method of any one of examples 14-16, wherein rotating the impeller includes rotating an axial impeller. 
     Example 18 includes the method of any one of examples 14-17, wherein rotating the impeller includes rotating a radial impeller. 
     Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein. 
     Although an overview of the inventive subject matter has been described with reference to specific example embodiments, various modifications and changes may be made to these embodiments without departing from the broader scope of embodiments of the present disclosure. Such embodiments of the inventive subject matter may be referred to herein, individually or collectively, by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any single disclosure or inventive concept if more than one is, in fact, disclosed. 
     The embodiments illustrated herein are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed. Other embodiments may be used and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. The Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled. 
     As used herein, the term “or” may be construed in either an inclusive or exclusive sense. Moreover, plural instances may be provided for resources, operations, or structures described herein as a single instance. Additionally, boundaries between various resources, operations, modules, engines, and data stores are somewhat arbitrary, and particular operations are illustrated in a context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within a scope of various embodiments of the present disclosure. In general, structures and functionality presented as separate resources in the example configurations may be implemented as a combined structure or resource. Similarly, structures and functionality presented as a single resource may be implemented as separate resources. These and other variations, modifications, additions, and improvements fall within a scope of embodiments of the present disclosure as represented by the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. 
     The foregoing description, for the purpose of explanation, has been described with reference to specific example embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the possible example embodiments to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The example embodiments were chosen and described in order to best explain the principles involved and their practical applications, to thereby enable others skilled in the art to best utilize the various example embodiments with various modifications as are suited to the particular use contemplated. 
     It will also be understood that, although the terms “first,” “second,” and so forth may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the present example embodiments. The first contact and the second contact are both contacts, but they are not the same contact. 
     The terminology used in the description of the example embodiments herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used in the description of the example embodiments and the appended examples, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     As used herein, the term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” may be construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context.