BRIEF DESCRIPTION OF THE DRAWINGS
The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
FIG. 1 is a perspective, partially sectional view of one embodiment of a refrigeration system of the present invention configured to cool a sealed electronics enclosure.
FIG. 2 is a cross sectional view of the refrigeration system of FIG. 1 along line 1-1.
FIG. 3 is an elevational view of the refrigeration system of FIG. 1 viewed from the right side of FIG. 2.
FIG. 4 is a fluid flow diagram the refrigeration system invention.
FIG. 5 is a cross sectional view of the refrigeration system of FIG. 1 along line 2-2.
FIG. 6 is an electrical flow diagram of the operations that comprise the refrigeration system of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms, therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
Turning first to FIG. 1 there is shown one embodiment of the self contained refrigeration system for sealed electronics enclosures, a computer or other electronics hereafter referred to as the sealed electronics enclosure refrigeration system (SEERS) S. SEERS 5 includes a sealed enclosure 6 fabricated of rigid material such as metal, plastic or other appropriate material, having operably disposed therein, a compact first heat exchanger in the form of an evaporator 9, an air flow generating device in the form of a bank of one or more evaporator fans and fan motors 10, an electronics system or electronics backplane in the form of circuit board connections 8, electronics circuit board(s) 12, an air flow separator plenum panel 13, and a SEERS 5 electronics controls circuit 18. In the preferred embodiment of the illustrated SEERS 5, the sealed enclosure 6 is constructed such that a thickness of insulation 7 may be applied for prevention of heat transfer through the sealed enclosure 6. FIG. 1 illustrates the SEERS 5 with the front cover panel 30 removed; disposed exterior to the SEERS 5 and attached adjacent to the rear outerwall of the sealed enclosure 6, a compact second heat exchanger in the form of a condenser 16 and an air flow generating device in the form of a bank of one or more condeser fans and fan motors 17.
FIG. 2 schematically illustrates the SEERS 5 of FIG. 1 along section view 1-1 and shows one embodiment of the SEERS 5 in which the condenser 16, condenser fans 17, condenser to evaporator refrigerant flow line 22, flow control valve 19, and compressor 20 are are all disposed exterior to the SEERS 5 and attached adjacent to the rear outerwall of the sealed enclosure 6. Turning now to FIG. 3 there is shown a side view of the exterior of the SEERS 5 that further illustrates one embodiment of the invention having a front cover 30 that may be attached to the four fixed side surfaces of the sealed enclosure 6 with screws, bolts, cam locks or other appropriate methods including the use of hinged connections on any front cover 30 edges. In alternative embodiments of the current invention, the front cover 30 may be relocated to replace any other exterior surface of the sealed enclosure 6, or multiple covers may be used to permit multi-axis entrance to the SEERS 5 sealed enclosure 6.
FIG. 3 clearly illustrates the condenser to evaporator refrigerant flow line 22, that in the preferred embodiment of the current invention passes through a sealed penetration in the rear outerwall of the sealed enclosure 6 and is in fluid communication with the condenser 15 by means of a flow control valve 19. FIG. 3 also shows the operable connection between the compressor and condenser as compressor to condenser refrigerant flow line 21, and compressor 20 mounted by means of bolts, welds, straps or other appropriate methods, on compressor stabilizer base 31 that is mounted on the external surface of the sealed enclosure 6 by means of welds, screws, bolts or other appropriate methods.
The Illustrated SEERS 5 embodiment requires no additional external or internal operably coupled devices or refrigerant connection lines to transfer heat from the SEERS 5 sealed enclosure 6 to ambient nor redirection of refrigerant or other chilled liquid to locations requiring heat transfer. A benefit of this embodiment of the current invention is the miniaturized volumetric footprint occupied by the SEERS 5 relative to the sealed enclosure 6 as compared to that of other two phase refrigerant cooling methods. Devices such as heat sinks, heat pipes thermosyphons or other appropriate heat dissipation devices may be fluidically or thermally coupled to local electronic components and the evaporator 9 to assist in the transfer of heat to the SEERS 5 evaporator 9, however, the current embodiment of the invention relates to the use of directed airflow generated by one or more evaporator fans and fan motors 10 as the carrier medium of heat from the sealed enclosure 6 electronic components and electronics board(s) 12 to the SEERS 5 evaporator 9.
In the preferred embodiment the SEERS 5 evaporator 9 is equipped with thermal exchange features, such as metal fins or other conductive materials in high surface area arrangements to provide enhanced collection of heat from airflow directed by one or more evaporator fans and fan motors 10 across electronic components and electronics board(s) 12. The term “thermal exchange features” used hereafter refers to any such mating surfaces attached to SEERS 5 evaporator 9 or condenser 16 through or over which heat can be passed to enhance heat transfer. In the preferred embodiment the SEERS 5 condenser 16 is equipped with thermal exchange features that inhibit entrapment of ambient particulates and moisture, and provide enhanced rejection of heat contained in compressed refrigerant vapor using airflow directed through or over the thermal exchange features by one or more condenser fans and fan motors 17. Two particular benefits of the SEERS 5, as compared to other cooling methods, arise as the result of the orientation of the evaporator 9 and evaporator fans and fan motors 10 located inside sealed enclsoure 6, namely 1) the capacity to produce highly turbulent air flow leading to enhanced heat transfer rates from heat generating electronics and 2) the capability to integrate focused turbulent air flow over particularly troublesome electronics hot spots through the use of air knives, air nozzels, cold plates attached to hot spots or other appropriate devices. The SEERS 5 compressor 20 can be of any type appropriate to a achieve efficient compression of refrigerant vapor. In the preferred embodiment of the invention, the SEERS 5 compressor 20 may be a positive displacement compressor, rolling piston compressor, scroll compressor or of any other approriate and sufficiently compact type or design that is disposed external to the sealed enclosure 6 so as to prevent additional internal heat generation due to vapor compression kinetics.
FIGS. 4, 5 and 6 schematically illustrate the operation of the SEERS 5 of FIG. 1. From fluid flow schematic FIG. 4, it is seen that during operation the compressor 20 collects suction side vaporized refrigerant from the evaporator 9, mechanically compresses vaporized refrigerant and discharges the high pressure refrigerant to condenser 16. Condenser 16, disposed external to sealed enclosure 6, removes heat 34 from the compressed refrigerant vapor to ambient by means of air flow generated by one or more condenser fans and fan motors 17 that is directed through or over thermal exchange features attached to condenser 16. Upon cooling, high pressure refrigerant vapor condenses to liquid by means of falling film condensation inside condenser 16 and is directed through evaporator fluid line 22 to fluid flow control device 19, such as a capillary tube or electromechanical valve disposed external to sealed enclosure 6. Reduced pressure liquid refrigerant is released by fluid flow control device 19 to evaporator 9, where it absorbs thermal energy generated by electronic components and electronics board(s) 12 disposed inside sealed enclosure 6 and is converted from liquid to vapor phase. Heat 35 transfer from electronic components and electronics board(s) 12 to evaporator 9 is enhanced by airflow through or over evaporator thermal exchange features from one or more evaporator fans and fan motors 10. Refrigerant vapor generated inside of evaporator 9 is directed through fluid line 21 to compressor 20 and the cycle is then repeated. A primary advantage of the SEERS 5 operation as described is that the evaporator 9 is disposed inside of the sealed enclosure 6 isolating it from ambient heat sources that can significantly decrease its heat absorption efficiency. Additionally, only clean dry air within the sealed enclosure 6 is distributed over or through evaporator 9 thermal exchange features preventing particulate or moisture fouling of the thermal exchange features. Moreover, the SEERS 5 design described eliminates the neccessity for large diameter airflow duct penetrations through sealed enclosure 6 surfaces, therefore increasing the reliability of enslosure penetration seals since only small diameter penetrations are necessary to pass refrigerant tubing and electrcial power lines between the internal and external surfaces of sealed enclosure 6. This latter feature also results in significantly less complex and less costly hermetic seal fabrication that possess longer mean time before failure.
FIG. 5 illustrates section 2-2 of FIG. 1, which demonstrates one possible embodiment of evaporator airflow 14 circulation generated by one or more evaporator fans and fan motors 10, that is heated across electronic components and electronics board(s) 12, transfers heat through vaporization of liquid refrigerant in evaporator 9 and returns to absorb additional heat from electronic components and electronics board(s) 12 as chilled airflow 15. In one embodiment of the invention an air flow separator plenum 13 of metal, plastic or other appropriate rigid material isolates heated evaporator airflow 14 from chilled airflow 15, thereby preventing mixing of the two and subsequent loss of evaporator efficiency. In other embodiments, separator plenum 13 may be placed in other locations within sealed enclosure 6 or possess alternative physical geometry or spacial orientation. Separator plenum 13 may also be in the form of a perforated airflow distribution weir of various configurations, an air flow distribution manifold supplying air flow to one or more air knives, air nozzels or a combination thereof to provide optimum airflow turbulence, velocity or mass flow rate across SEERS 5 heat generating components.
Referring now to FIG. 6, the current embodiment of SEERS 5 is illustrated as an electrical flow diagram. AC power supply/converter 25 is disposed inside sealed enclosure 6 and operably coupled to DC power supply 24, also disposed inside sealed enclosure 6. DC power supply 24 provides 24-volt DC power to one or more condenser fans and fan motors 17, compressor 20, SEERS electronic control circuit 18, flow control valve 19, and one or more evaporator fans and fan motors 10, by means of wired DC power connections 33. In the preferred embodiment of the invention, SEERS electronic control circuit 18 is operably coupled by wired digital or analog DC signal connections 32 to one or more temperature sensors 26 that may be attached to local heat generating sources or other devices or components, data acquisition electronics boards 12, DC power supply 24, one or more evaporator fans and fan motors 10, one or more condenser fans and fan motors 17, and compressor 20. FIG. 6 distinguishes the SEERS 5 components that are completely or partially disposed inside of sealed enclosure 6 and therefore exposed only to inside enclosure air 28 from those completely or partially disposed outside of sealed enclosure 6 and therefore exposed only to ambient air 29. Disposal of AC power supply/converter 25, DC power supply 24 and electronic control circuit 18 inside of sealed enclosure 6 provides two distinct advantages over prior art: 1) these are typically heat generating devices with efficiency curves inversely proportional to operating temperature, therefore cooling these components inside enclosure 6 prevents degradation of operating efficiency and 2) these components are protected from exposure to potentially damaging sunlight, particulates and moisture.
As indicated in FIG. 6, temperature sensors 26 may either individually or in conjunction with specialized data acquisition electronics boards 12 provide digital or analog data to electronic control circuit 18 which uses stored computer algorithms to compare collected data to set point values that benchmark minimum or maximum acceptable component or SEERS 5 system operating threshold values. Benchmark values may be in the form of component temperature, air temperature, power consumption, duration of component operating interval, fault signals or other appropriate data that can be used to asses system function by the electronic control circuit 18. Based upon comparing sensor data to benchmark values, electronic control circuit 18 may send signals by means of wired digital or analog DC signal connections 32 to DC power supply 24 causing initiation or termination of 24-volt DC power to one or all of SEERS 5 components. Electronic control circuit 18 may further be programmed to provide for initiation or termination of 24-volt DC power to one or all of SEERS 5 components based upon conditional timer algorithms, conditional power consumption algorithms, conditional temperature comparator algorithms or other appropriate methods that are meant ensure proper SEERS system operation and protection of any or all electronic components and electronics board(s) 12 from thermal damage. The benefits of the described embodiment of operation of the invention are: 1) criti SEERS 5 and electronic components and electronics board(s) 12 may be individually monitored for operational health by data acquired from temperature sensors 26 and/or other data acquisition electronics boards 12, therefore all components can be evaluated individually and their health and operation prioritized, 2) electronic control circuit 18 can terminate or initiate operation of individual components whose function or lack thereof might otherwise cause damage to other components, and 3) electronic control circuit 18 can power down critical component(s) or all non-SEERS 5 related computer electronics while maintaining operation of the SEERS 5 cooling systems to enable proper cool down during or after shutdown and prior to reboot or startup. During normal operation, electronic control circuit 18 will evaluate acquired data from the sources described and initiate and terminate SEERS 5 cooling system operation in order to protect all system components from thermal damage.
The refrigeration system of the present invention has been described herein as including a converter that is operably coupled to an AC power supply and which provides DC power to refrigeration system components. It is however also possible for the converter to be couple to a DC power supply and/or an AC power supply and therefore may use either power input type that is available to provide conditioned DC or AC power to all SEERS 5 component described.
This invention has been described as A Compact Refrigeration Apparatus for Cooling Sealed Electronics Enclosures, but is intended to cover other applications involving electronic system cooling including, but not limited to, cooling liquid crystal display (LCD) glass in indoor and outdoor applications, cooling various video display lamps or light sources that generate heat within electronics enclsoures and combinations of computer electronics and video display systems integrated into a single sealed electronics enclsosure.
This invention has been described as having an exemplary design leading to the noteworthy benefits also described herein. The present invention may however be further modified within the spirit and scope of this disclosure to therefore cover any variations, uses or adaptations of the invention using its general design and operational principles.
While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
Patent Application
20080060371
