Direct Cooling Platform With Vapor Compression Refrigeration Cycle And Applications Thereof

Abstract

A direct refrigeration cooling platform can cool high heat density sources such as LEDs, IC chip, power amplifiers and laser diodes. The platform utilizes a combination of technologies from a water cooled cold plate design and a vapor compression refrigeration system. The cold plate of the direct refrigeration cooling platform replaces an evaporator in a conventional vapor compression refrigeration cycle. High heat density sources are directly mounted onto the cold plate. Temperature of the cold plate is regulated based on temperature feedback and is maintained above ambient temperatures. For LED applications, a number of LEDs are mounted onto the cold plate of the direct refrigeration cooling platform. Beams of light are distributed via fiber optic light guides to remote and inaccessible locations, where light sources are to be replaced. IC chips are cooled the same way with IC chips attached to the cold plate of the direct refrigeration cooling platform.

Description

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

The present disclosure claims the priority benefit of U.S. Patent Application Ser. No. 62/301,971, filed on 1 Mar. 2016, and U.S. Patent Application Ser. No. 62/372,306, filed on 9 Aug. 2016, which are incorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure is generally related to image processing in electronic apparatuses and, more particularly, to thermodynamics and heat transfer and, particularly, to a vapor compression refrigeration cooling system.

BACKGROUND

Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted to be prior art by inclusion in this section.

Light emitting diodes (LEDs) have been used widely in medical to military applications. One challenging problem for the usage of LEDs is the removal of heat generated by the LEDs, so that the LEDs can operate within diode operating temperatures to avoid shortened life due to operation under high temperature for a prolonged period of time. A common way to cool LEDs is to use a heatsink with a fan. However, in an environment of high-power LED operation, the use of a chiller is often necessary. The chiller circulates cold water and removes heat away from LEDs. In a conventional chiller a vapor compression refrigeration system is used to provide cold water. However, the use of a chiller with water circulation tends to increase the form factor substantially as well as the operating cost of an overall cooling system.

A vapor compression refrigeration cycle generally consists of a compressor, a condenser, an expansion valve, an evaporator and a refrigerant, which are elements of a recirculating circuit connected by tubing. The refrigeration cycle rejects heat at the condenser and absorbs heat at the evaporator. Thus, the temperature in an environment at and around the evaporator is typically lower than the surrounding ambient environment. Moreover, work energy is required to drive the cycle at the compressor.

SUMMARY

The following summary is illustrative only and is not intended to be limiting in any way. That is, the following summary is provided to introduce concepts, highlights, benefits and advantages of the novel and non-obvious techniques described herein. Select and not all implementations are further described below in the detailed description. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter.

The present disclosure proposes a new cooling apparatus which is herein referred to as a direct refrigeration cooling platform, which utilizes a vapor compression refrigeration cycle to cool heat sources directly via a cold plate. Different from the vapor compression refrigeration cycle employed in conventional chillers, in various embodiments of a direct refrigeration cooling platform in accordance with the present disclosure the cold plate may be used in lieu of an evaporator in the vapor compression refrigeration system. Moreover, a refrigerant, instead of water which is typically used in conventional chillers, may be used as a cooling medium for the cold plate. In various embodiments of the direct refrigeration cooling platform in accordance with the present disclosure, heat sources such as LEDs and integrated-circuit (IC) chips may be directly mounted onto the cold plate.

The direct refrigeration cooling platform may use a relatively small volume of a refrigerant such as, for example and without limitation, R-134a, R-410A and/or R-407C. Advantageously, this relatively small volume is sufficient to dissipate a large amount of energy while keeping the form factor of the overall system small. In addition, no external plumbing connections are required, thereby simplifying the installation and reducing the cost of ownership of a direct refrigeration cooling platform in accordance with the present disclosure.

As heat sources such as LEDs and IC chips may be mounted onto the cold plate directly, the cold plate may be used as a heat spreader and may function as or otherwise replace an evaporator. Heat from the heat sources may thus be directly absorbed by a refrigerant as the refrigerant undergoes a phase change from liquid to gas while flowing through the cold plate. Heat may then be rejected to an environment as the refrigerant flows through a condenser, where the refrigerant undergoes a phase change from gas to liquid.

In various embodiments of the direct refrigeration cooling platform in accordance with the present disclosure, the compressor and the thermal expansion valve may be electronically controlled to regulate the flow rate of the refrigerant, or refrigerant flow rate. The compressor may increase a pressure of the refrigerant in a gaseous phase. The refrigerant flow rate may be changed by changing a rotational speed, in revolutions per minute (RPM), of the compressor. The thermal expansion valve may decrease the pressure of the refrigerant in a liquid phase. The refrigerant flow rate may be changed by throttling up and down the thermal expansion valve.

In various embodiments of the direct refrigeration cooling platform in accordance with the present disclosure, a temperature feedback control may be performed. Temperature sensors may be mounted onto the cold plate to sense the temperature(s) of the cold plate at one or more spots. A central processing unit (CPU) may detect temperature changes in the cold plate and transmit signals to control the RPM of the compressor and/or the thermal expansion valve. Hence, temperature of the cold plate may be kept relatively constant regardless of the amount of heat transferred from the heat sources to the cold plate. The temperature of the cold plate may be kept above an ambient temperature to prevent any dew point condensation.

In one aspect, an apparatus may include: a compressor capable of compressing a refrigerant; a condenser capable of cooling and condensing the refrigerant; a thermal expansion valve capable of evaporating at least a portion of the refrigerant; a cold plate capable of receiving one or more heat sources for the one or more heat sources to be disposed on the cold plate; and a tubing connecting the compressor, the condenser, the thermal expansion valve, and the cold plate such that the refrigerant undergoes a vapor compression refrigeration cycle as the refrigerant flows through the compressor, the condenser, the thermal expansion valve and the cold plate via the tubing. At least a portion of heat from the one or more heat sources may be absorbed by the refrigerant via the cold plate.

In some implementations, the cold plate may be made of a metallic material, and wherein the metallic material comprises aluminum or copper.

In some implementations, the cold plate may be made of a non-metal material. In some implementations, the non-metal material may include silicon, beryllium oxide or aluminum nitride.

In some implementations, when viewed from at least one angle, the cold plate may be round, oval, elliptical or polygonal in shape.

In some implementations, an outer surface of the cold plate may be plated, anodized or chem-filmed.

In some implementations, the cold plate may include one or more internal flow channels therein for the refrigerant to flow through the cold plate in either a serial fashion or a parallel fashion.

In some implementations, a surface of the one or more internal flow channels of the cold plate may have a plating thereon.

In some implementations, a surface of the cold plate exposed to an ambient may be thermally insulated with paint, polymer coating, hard anodizing, or a thermal-insulation material.

In some implementations, the apparatus may also include a temperature sensor, a first circuit and a second circuit. The temperature sensor may be disposed on or embedded in the cold plate, and may be capable of sensing a temperature of the cold plate and providing temperature data indicating the sensed temperature. The first circuit may be associated with the compressor, and may be capable of detecting a rotational speed of the compressor and providing a first data indicating the detected rotational speed. The first circuit may be also capable of adjusting the rotational speed of the compressor in response to receiving a first control signal. The second circuit may be associated with the thermal expansion valve, and may be capable of detecting a position of the thermal expansion valve and providing a second data indicating the detected position. The second circuit may be also capable of adjusting the position of the thermal expansion valve in response to receiving a second control signal.

In some implementations, the apparatus may further include a central processing unit (CPU) communicatively coupled to receive the temperature data, the first data, and the second data from the temperature sensor, the first circuit, and the second circuit, respectively. The CPU may be capable of controlling the temperature of cold plate by providing either or both of the first control signal and the second control signal to the first circuit and the second circuit, respectively.

In some implementations, the apparatus may further include an ambient temperature sensor capable of sensing a temperature of an ambient in which the cold plate is situated. The CPU may maintain the temperature of the cold plate above the sensed temperature of the ambient.

In some implementations, the CPU may be capable of receiving a user input that sets a user-preset temperature, and the CPU may maintain the temperature of the cold plate within a range of ±20° C. from the user-preset temperature.

In some implementations, the CPU may maintain the temperature of the cold plate within a range of −40° C. to 150° C.

In some implementations, the apparatus may also include the one or more heat sources. In some implementations, the one or more heat sources may include at least a light emitting diode (LED), an integrated-circuit (IC) chip, an amplifier, or a laser diode. In some implementations, the apparatus may further include a fiber optic light guides coupled to the LED to guide at least a portion of a light emitted by the LED to a remote location. In some implementations, the one or more heat sources may be directly mounted onto the cold plate by one or more screws, one or more brackets, one or more springs, or a combination thereof. In some implementations, the apparatus may further include a cover plate that secures the one or more heat sources onto the cold plate.

In some implementations, the apparatus may also include the refrigerant, which may be R-134a, R-410A or R-407C.

Advantageously, various embodiments of the direct refrigeration cooling platform in accordance with the present disclosure may be used with any heat source such as LEDs, IC chips, power amplifiers, laser diodes, and so on. For LED applications, a number of LEDs may be mounted onto the cold plate of the direct refrigeration cooling platform, and beams of light may be delivered to remote illumination areas via fiber optic light guides. Thus, change-out of the LEDs may be performed at an easily accessible and centralized location. For IC chip applications, IC chips may be directly mounted onto the cold plate. Thus, a large amount of heat generated by the IC chips may be removed with a small heat-sinking form factor.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of the present disclosure. The drawings illustrate implementations of the disclosure and, together with the description, serve to explain the principles of the disclosure. It is appreciable that the drawings are not necessarily in scale as some components may be shown to be out of proportion than the size in actual implementation in order to clearly illustrate the concept of the present disclosure.

FIG. 1 is a diagram of a high-level design of a direct refrigeration cooling platform, the various embodiments of which may be implemented in accordance with the present disclosure.

FIG. 2 is a perspective view of an example implementation of a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure.

FIG. 3 is a perspective view of an example implementation of a direct refrigeration cooling platform with fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 4 is a left perspective view of an example implementation of a direct refrigeration cooling platform with fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 5 is a detailed perspective view of an example implementation of a cold plate and fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 6 is a detailed exploded view of an example implementation of a cold plate and fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 7 is a perspective view of an example implementation of a single-channel cold plate in accordance with an embodiment of the present disclosure.

FIG. 8 is a perspective view of an example implementation of a multiple-channel cold plate with a series flow in accordance with an embodiment of the present disclosure.

FIG. 9 is a perspective view of an example implementation of a multiple-channel cold plate with a parallel flow in accordance with an embodiment of the present disclosure.

FIG. 10 is a tunnel LED lighting application with a direct refrigeration cooling platform and fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 11 is an automobile LED headlamp lighting application with a direct refrigeration cooling platform and fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 12 is an ultraviolet (UV) LED lighting application for drying inks on paper during printing operation using a direct refrigeration cooling platform and fiber optic light guides in accordance with an embodiment of the present disclosure.

FIG. 13 is a perspective view of an IC chip cooling application with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure.

FIG. 14 is a left perspective view of an IC chip cooling application with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure.

FIG. 15 is a perspective view of a vehicle refrigeration system with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure.

FIG. 16 is a perspective view of on-demand air/water sterilization system with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

Overview

Various embodiments disclosed herein pertain to a direct refrigeration cooling platform, which utilizes a vapor compression refrigeration cycle. Compared to conventional chillers, embodiments of the direct refrigeration cooling platform in accordance with the present disclosure does not require a bulky water-based heat exchange system. Moreover, external plumbing is eliminated in embodiments of the direct refrigeration cooling platform in accordance with the present disclosure.

FIG. 1 depicts a high-level design of a direct refrigeration cooling platform 100, the various embodiments of which may be implemented in accordance with the present disclosure. Referring to FIG. 1, direct refrigeration cooling platform 100 may include a vapor compression refrigeration cycle including four major components, namely a cold plate 101, a compressor 102, a condenser 103 and a thermal expansion valve 104. On the one hand, compressor 102, condenser 103 and thermal expansion valve 104 may be implemented with a compressor, condenser and a thermal expansion valve similar to those employed in conventional vapor compression refrigeration cycles. On the other hand, the evaporator in conventional vapor compression refrigeration cycles is replaced by cold plate 101 in direct refrigeration cooling platform 100.

In a thermodynamic cycle of direct refrigeration cooling platform 100, a circulating refrigerant enters compressor 102 as a vapor. The vapor is compressed at constant entropy and exits compressor 102 superheated. The superheated vapor travels through condenser 103, which first cools and removes the superheat from the vapor and then condenses the vapor into a liquid by removing additional heat at constant pressure and temperature. The liquid refrigerant goes through thermal expansion valve 104 where the pressure of the refrigerant abruptly decreases, causing flash evaporation and auto-refrigeration of at least a portion of the liquid. This results in a mixture of liquid and vapor at a lower temperature and pressure. The cold liquid-vapor mixture then travels through cold plate 101 and is completely vaporized by cooling one or more heat sources disposed on or otherwise in contact with cold plate 101. The resulting refrigerant vapor returns to compressor 102 to complete the thermodynamic cycle.

Cold plate 101 may be made of a metallic material with a high thermal conductivity such as, for example and without limitation, aluminum, copper or aluminum nitride for a uniform and fast heat transfer. Alternatively, cold plate 101 may be made of a non-metal material with a high thermal conductivity such as, for example and without limitation, silicon, beryllium oxide, aluminum nitride or a type of ceramics. Cold plate 101 may be used to function as a heat spreader and heatsink.

One or more heat-generating devices, or heat sources, may be directly mounted on, coupled to, affixed to or otherwise disposed on cold plate 101 such that at least a portion of the heat in the one or more heat sources may be transferred to cold plate 101 by thermal conduction. For example, heat sources such as LEDs may be directly mounted onto cold plate 101 by means of, for example and without limitation, soldering, brazing or mechanically secured with screws or/and brackets or/and springs. Cold plate 101 may thus provide both electrical insulation and thermal conduction.

In direct refrigeration cooling platform 100, any suitable refrigerant may be used to flow through the refrigeration cycle. Refrigerant such as, for example and without limitation, R-134a, R-410A and R-407C may be utilized in direct refrigeration cooling platform 100. Accordingly, cold plate 101 may have one or more internal flow channels for the refrigerant to flow through cold plate 101. The one or more internal flow channels of cold plate 101 may be arranged in series or in parallel. That is, the one or more internal flow channels may be configured or arranged such that the refrigerant may flow through cold plate 101 in a serial fashion or in a parallel fashion.

Cold plate 101 may have two or more holes corresponding to the one or more internal flow channels. Inlet and outlet ports may be soldered onto such holes of cold plate 101. Pipe threads may be tapped onto the holes of cold plate 101. Moreover, cold plate 101 may have through holes and/or tapped screw holes that may be used for securing diodes, IC chips and any heat source components onto cold plate 101. The outer surface of cold plate 101 may be plated with zinc, nickel or chrome to prevent surface oxidization. In cases in which cold plate 101 is made of aluminum, the outer surface of cold plate 101 may be chem-filmed or anodized. As for the internal flow channels of cold plate 101 through which the refrigerant flows, there may be no finishes or, alternatively, may have a plating on the surfaces thereof.

When viewed from at least one angle, cold plate 101 may be round, oval, elliptical or polygonal in shape. For example, cold plate 101 may be triangular, square, rectangular, pentagonal, hexagonal or octagonal. Edges and corners of cold plate 101 may be rounded off to reduce surface areas. Surfaces of cold plate 101 that are exposed to an ambient may absorb heat from the surrounding. Such surfaces may be thermally insulated by a paint, rubber coating, polymer coating, insulation foam, hard anodizing or any other suitable thermal-insulation technique.

In direct refrigeration cooling platform 100, a feedback control system that includes a central processing unit (CPU) 174 may be provided. CPU 174 may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, or one or more complex-instruction-set-computing (CISC) processors. Moreover, CPU 174 may be implemented as one or more processors of a computing apparatus such as, for example and without limitation, a smartphone, a laptop computer, a notebook computer, a tablet computer, a desktop computer, a server, a wearable computing device, any combination of two or more thereof, or any variation thereof.

As illustrated in FIG. 1, CPU 174 may be coupled to receive temperature data regarding one or more temperature readings on one or more spots of cold plate 101. Additionally, CPU 174 may be coupled to receive compressor data (e.g., RPM) from compressor 101 as well as valve data (e.g., valve positioning being fully closed, fully open, ½ open, ⅓ open, ¼ open, ¾ open and so on) from thermal expansion valve 104. Furthermore, CPU 174 may be coupled to transmit control signals to control each of compressor 102 and thermal expansion valve 104 to control a flow rate of the refrigerant and thereby adjust or maintain a temperature of cold plate 101. For instance, direct refrigeration cooling platform 100 may include a number of temperature sensors mounted on or otherwise coupled, affixed or attached to cold plate 101 to sense the temperature(s) of one or more spots of cold plate 101 and provide temperature data to CPU 174.

In operation, CPU 174 may, based on the temperature data, detect temperature changes in cold plate 101 and, as a result, transmit control signal(s) to either or both of compressor 102 and thermal expansion valve 104 to increase or decrease the RPM of compressor 102 and/or to throttle up or down thermal expansion valve 104. The control signal(s) from CPU 174 to either or both of compressor 102 and thermal expansion valve 104 may cause the flow rate of the refrigerant to increase or decrease to adjust the rate at which heat, or thermal energy, in cold plate 101 is carried away by refrigerant, thereby increasing or decreasing the temperature of cold plate 101. For example, to lower or decrease the temperature of cold plate 101, CPU 174 may transmit control signal(s) to decrease the RPM of compressor 102 and/or throttle down thermal expansion valve 104.

In some embodiments, CPU 174 may maintain the temperature of cold plate 101 above an ambient temperature to prevent any dew point condensation from forming. For example, there may be one or more temperature sensors arranged to sense the ambient temperature and provide temperature data, indicating the sensed ambient temperature, to CPU 174. Thus, CPU 174 may maintain the temperature of cold plate 101 based on the sensed ambient temperature by controlling the RPM of compressor 102 and/or valve position (between being fully open and being fulling closed) of thermal expansion valve 104.

In some embodiments, CPU 174 may accept user input from a user to preset or otherwise predefine a desired temperature of cold plate 101. Accordingly, CPU 174 may maintain a temperature of cold plate 101 within a certain range of the desired temperature preset by the user (e.g., within a range of ±10° C. thereof), with the minimum temperature of cold plate 101 being kept above the ambient temperature. Thus, an operational temperature range of cold plate 101 may be in the range of −40° C. to 150° C.

For illustrative purposes and without limiting the scope of the present disclosure, a number of example implementations based on direct refrigeration cooling platform 100 are described below with reference to FIGS. 2-16.

Example Implementations

FIG. 2 depicts an example implementation of a direct refrigeration cooling platform 5001 in accordance with an embodiment of the present disclosure. FIG. 3 depicts an example implementation of a direct refrigeration cooling platform 5001 with fiber optic light guides 3001 in accordance with an embodiment of the present disclosure. FIG. 4 depicts an example implementation of a direct refrigeration cooling platform 5001 with fiber optic light guides 3001 in accordance with an embodiment of the present disclosure. FIG. 5 depicts an example implementation of cold plate 201 and fiber optic light guides 3001 in accordance with an embodiment of the present disclosure. FIG. 6 depicts an example implementation of cold plate 201 and fiber optic light guides 3001 in accordance with an embodiment of the present disclosure. FIG. 7 depicts an example implementation of a single-channel cold plate 201 in accordance with an embodiment of the present disclosure. FIG. 8 depicts an example implementation of a multiple-channel cold plate 291 with a series flow in accordance with an embodiment of the present disclosure. FIG. 9 depicts an example implementation of a multiple-channel cold plate 311 with a parallel flow in accordance with an embodiment of the present disclosure.

The following components are shown in FIGS. 2-9: cold plate 201, compressor 202, condenser 203, thermal expansion valve 204, cover plate 212, holder of fiber optic light guide 213, fiber optic light guide #1 214, light emitting diode (LED) 215, base plate 216, thermal interface material 217, fiber optic light guide #2 218, fiber optic light guide #3 219, beam of light 220, outlet hole #1 of refrigerant flow and tube connection 241, through hole or tapped screw hole #1 242, through hole or tapped screw hole #n 243, inlet hole #1 of refrigerant flow and tube connection 244, internal flow channel #1 of single-channel cold plate 245, tube connection between cold plate and thermal expansion valve 251, tube connection between cold plate and compressor 252, tube connection between condenser and compressor 253, tube connection between condenser and thermal expansion valve 254, printed circuit board assembly (PCBA) of CPU, compressor power and RPM control 261, PCBA of thermal expansion valve control and power 262, temperature sensor #1 265, temperature sensor #2 266, voltage cable for compressor power 271, ground cable for compressor power 272, signal cable for compressor RPM control 273, central processing unit (CPU) 274, temperature probe cable #1 275, temperature probe cable #2 276, signal cable for thermal expansion valve control 277, mounting plate for direct refrigeration cooling platform 281, cold plate with multiple internal flow channels in a series flow 291, outlet hole #2 of refrigerant flow and tube connection 292, inlet hole #2 of refrigerant flow and tube connection 293, internal flow channel #1 of multiple-channel cold plate in a series flow 294, internal flow channel #2 of multiple-channel cold plate in a series flow 295, internal flow channel #n of multiple-channel cold plate in a series flow 296, tube #1 for refrigerant channel connection in multiple-channel cold plate in a series flow 297, tube #2 for refrigerant channel connection in multiple-channel cold plate in a series flow 298, through hole or tapped screw hole #10 299, cold plate with multiple internal flow channels in a parallel flow 311, outlet hole #10 of refrigerant flow 312, inlet hole #10 of refrigerant flow 313, internal flow channel #1 of multiple-channel cold plate in a parallel flow 314, internal flow channel #2 of multiple-channel cold plate in a parallel flow 315, internal flow channel #n of multiple-channel cold plate in a parallel flow 316, tube #10 for refrigerant channel connection in multiple-channel cold plate in a parallel flow 317, tube #11 for refrigerant channel connection in multiple-channel cold plate in a parallel flow 318, and through hole or tapped screw hole #20 319.

In direct refrigeration cooling platform 5001, a cold plate 201 replaces an evaporator in a conventional vapor compression refrigeration system, which typically consists of an evaporator. Direct refrigeration cooling platform 5001 also includes a condenser 203, a thermal expansion valve 204 and a compressor 202. Cold plate 201 may be made of a metallic material or a non-metal material with a high thermal conductivity such as aluminum, copper, aluminum nitride or silicon for a uniform and fast heat transfer.

In at least one embodiment, LEDs 215 may be directly mounted onto cold plate 201 by means of soldering, brazing or mechanically secured with screws or/and brackets or/and springs. Cold plate 201 may function as a heat spreader and heatsink for LEDs 215.

In at least one embodiment, LEDs 215 may be packaged with the base plate, 216, made of non-metals with a high thermal conductivity such as silicon, beryllium oxide or aluminum nitride are directly mounted onto the cold plate, 201, by means of soldering, brazing or mechanically secured with screws or/and brackets or/and springs. The base plate with a high thermal conductivity provides electrical insulation while providing a high thermal conduction path.

In at least one embodiment, cover plate 212 may be made of a metallic material or a non-metal material with a high thermal conductivity such as aluminum or copper. Cover plate 212 may be used to secure diodes 215 (or any other type of heat source(s)) to the cold plate 201. With the thermal interface material 217, such as indium for example, inserted between cold plate 201 and diodes 215, material thermal expansion mismatch between cold plate 201 and diodes 215 may be eliminated. The cover plate 212 may be used as a heatsink and mounted using screws or/and brackets.

In at least one embodiment, refrigerants such as R-134a, R-410A and R-407C may flow through internal flow channel(s) of cold plate 201 where inlet and outlet ports of the cold plate 201 are soldered onto cold plate holes 241 and 244. Pipe threads may be also tapped on cold plate holes 241 and 244. Cold plate 201 may have through holes or/and tapped screw holes 242 and 243, which can be used for securing diodes, IC chips and any heat source components onto cold plate 201. The outer surface of cold plate 201 may be plated with zinc, nickel or chrome to prevent surface oxidization. In cases in which cold plate 201 is made of aluminum, the outer surface of cold plate 201 may be chem-filmed or anodized. Internal flow channels 245, 294, 295, 296, 314, 315 and 316 of cold plates 201, 291 and 311 may have no finishes or, alternatively, may have a plating on the surfaces thereof.

In at least one embodiment, the shape of cold plates 201, 291 and 311 may be rectangular, square, triangular, round, hexagonal or octagonal. Edges and corners are rounded off to reduce surface areas. Cold plate surfaces exposed to an ambient will absorb heat from the surrounding. These surfaces can be thermally insulated with a paint, rubber coating, polymer coating, insulation foam, hard anodizing or any suitable thermal-insulation technique.

In at least one embodiment, temperature sensors 265 and 266 may be attached to the cold plate 201. Temperature sensors are used to control the flow rate of refrigerants such as R-134a, R-410A and R-407C. As the cold plate temperature increases, CPU 274 may detect temperature changes via temperature sensors 265 and 266, and may transmit control signals to increase the RPM of compressor 202 or/and to throttle up thermal expansion valve 204. These inputs may cause the refrigerant flow rate to increase and the cold plate temperature to decrease. To decrease the cold plate temperature, the RPM of compressor 202 may be decreased or/and thermal expansion valve 204 may be throttled down. Hence, a feedback control system is established.

In at least one embodiment, cold plate 201 may be kept above the ambient temperature to prevent any dew point condensation. CPU 274 may detect the ambient temperature and keep cold plate 201 above the ambient temperature by controlling the RPM of compressor 202 or/and position of thermal expansion valve 204. When the cold plate temperature is preset by a user, direct refrigeration cooling platform 5001 may be operated at the preset temperature ±10° C., where the minimum temperature may be above the ambient temperature. An operational temperature range of the cold plate 201 may be, for example and without limitation, in the range of −40° C. to 150° C.

As cold plate 291 and cold plate 311 are variations of cold plate 201, some or all of the above-described features of cold plate 201 are also applicable to cold plate 291 and cold plate 311. Thus, in the interest of brevity, a detailed description of each of cold plate 291 and cold plate 311 is not provided herewith to avoid redundancy.

In at least one embodiment, various LEDs such as ultra violet (UV), white light and infrared (IR) may be cooled using the direct refrigeration cooling platform 5001. Beams of light may be delivered with or without fiber optic light guides 3001. The direct refrigeration cooling platform 5001 may cool multiple LEDs in a centralized location and delivers beams of light to remote illumination areas via fiber optic light guides. Advantages of using direct refrigeration cooling platform 5001 include, for example and without limitation: 1) LEDs will operate at user's preset temperature with no risk of diode overheating; 2) no LED needs to be replaced at illumination areas, as all LEDs are replaced at a centralized ground location; and 3) there is no risk of the LED wavelength shift due to overheating of LEDs because a relatively constant temperature is maintained in the cold plate.

FIG. 10 depicts a tunnel LED lighting application 6001 with a direct refrigeration cooling platform and fiber optic light guides in accordance with an embodiment of the present disclosure. FIG. 11 depicts an automobile LED headlamp lighting application 7001 with a direct refrigeration cooling platform and fiber optic light guides in accordance with an embodiment of the present disclosure. FIG. 12 depicts an UV LED lighting application 8001 for drying inks on paper during printing operation using a direct refrigeration cooling platform and fiber optic light guides in accordance with an embodiment of the present disclosure. FIG. 13 depicts a perspective view of an IC chip cooling application 9001 with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure. FIG. 14 depicts a left perspective view of IC chip cooling application 9001. FIG. 15 depicts a perspective view of a vehicle refrigeration system 9500 with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure. FIG. 16 depicts a perspective view of on-demand air/water sterilization system 9600 with a direct refrigeration cooling platform in accordance with an embodiment of the present disclosure.

The following components are shown in FIGS. 10-16: fiber optic light guide #1 601, fiber optic light guide #2 602, fiber optic light guide #3 603, fiber optic light guide #4 604, fiber optic light guide #5 605, tunnel 609, automobile 610, paved road 611, right fiber optic light guide 710, left fiber optic light guide 711, left light reflector 712, right light reflector 713, left LED 721, right LED 722, fiber optic light guide #1 801, fiber optic light guide #2 802, fiber optic light guide #3 803, fiber optic light guide #4 804, fiber optic light guide #5 805, fiber optic light guide #6 806, fiber optic light guide #7 807, fiber optic light guide holder 811, left printing roller 812, right printing roller 813, roll of paper 815, direction of right roller rotation 817, direction of left roller rotation 818, beams of light 820, bottom PCBA with IC chip 901, top PCBA with IC chip 902, IC chip on top PCBA 905, IC chip on bottom PCBA 906, manifold of refrigerant flow 92, heat-generating component 921, vehicle evaporator 922, evaporator fan 923, thermal expansion valve for vehicle evaporator 925, thermal expansion valve for vehicle LED headlights 926, thermal expansion valve for heat-generating components 927, cold plate for heat-generating components 928, cold pate for vehicle LED headlights 929, temperature sensor at cold plate of heat-generating components 931, temperature sensor at cold plate of vehicle LED headlights 932, tube connection between evaporator and manifold 941, tube connection between cold plate and manifold 942, optically clear water pipe or air duct 951, holder of UV-LED fiber optic light guides 952, outlet pipe 953, inlet pipe 954, outlet flow sensor 955, inlet flow sensor 956, direction of fluid at outlet 957, direction of fluid at inlet 958, fiber optic light guide #1 961, fiber optic light guide #2 962, fiber optic light guide #3 963, fiber optic light guide #4 964, LEDs and fiber optic light guides 3001, vehicle air conditioning system (including thermal expansion valve) 4001, vehicle LED headlight cooling system (including thermal expansion valve) 4002, vehicle heat-generating component cooling system including thermal expansion valve 4003, direct refrigeration cooling platform 5001, direct refrigeration cooling platform with a refrigerant distribution manifold 5002, tunnel LED lighting application 6001, automobile LED headlight application 7001, UV LED lighting application 8001, IC chip cooling application 9001, vehicle refrigeration system 9500, and on-demand air/water sterilization system 9600 with UVC-LEDs.

In FIGS. 13 and 14, direct refrigeration cooling platform 5001 may be used to cool IC chips 905 and 906 in PCBAs 901 and 902. The top of IC chips, where heat-sinking is normally performed, may be directly attached to cold plate 201. Direct refrigeration cooling platform 5001 may keep the cold plate temperature relatively constant and above the ambient temperature regardless of the amount of heat output from IC chips 905 and 906. All of these are accomplished by the feedback control function of the direct refrigeration cooling platform 5001.

FIG. 15 illustrates a vehicle refrigeration system 9500 with a direct refrigeration cooling platform 5002, which has a refrigerant distribution manifold 920. The vehicle refrigeration system 9500 may contain a vehicle air conditioning system 4001, a vehicle LED headlight cooling system 4002, and a vehicle heat producing component cooling system 4003. Thermal expansion valves 925, 926 and 927 may control the refrigerant flow rate on each cooling system. When not used, the cooling system 4002 may be shut off by thermal expansion valves 925, 926 and 927. Manifold 920 may distribute a refrigerant to each cooling system.

FIG. 16 illustrates an UVC-LED on-demand air/water sterilization system 9600 with direct refrigeration cooling platform 5001. Delivery of a high sterilization dose is achievable with the direct refrigeration cooling platform 5001. The system 9600 may be designed to operate on demand as the ultraviolet (UVC) light turns on when flow sensors 955 and 956 detect flow of a fluid to be sterilized. The UVC light may turn off when no flow is detected. The system 9600 may be designed to deliver reduction in air/water borne pathogens by at least a magnitude of 2 log as fluid passes through pipe 951.

In view of the above, some features of the present disclosure are highlighted below.

LEDs (or another type of heat sources) may be directly mounted onto the cold plate of the direct refrigeration cooling platform to remove heat.

Heat sources such as an IC chip and laser diode may be directly mounted onto the cold plate of the direct refrigeration cooling platform to remove heat.

LEDs (or another type of heat sources) may be directly mounted onto the cold plate by means of soldering, brazing or mechanically secured with screws or/and brackets or/and springs.

Heat sources such as an IC chip and laser diode may be directly mounted onto the cold plate by means of mechanically secured with screws or/and brackets or/and springs.

LEDs packaged in the base plate made of non-metals with a high thermal conductivity, such as silicon, beryllium oxide or aluminum nitride, may be directly mounted onto the cold plate by means of soldering, brazing or mechanically secured with screws or/and brackets or/and springs.

Cold plates made of a metal or non-metal with a high thermal conductivity may be attached to the evaporator section of a vapor compression refrigeration cycle.

Cold plates may have through holes or/and tapped screw holes for securing LEDs, IC chips, and any heat sources.

Cold plates may have internal flow channel(s) built in for a refrigerant flow. The internal flow channels may be arranged either in parallel or in series.

Cold plate surface areas exposed to an ambient may be thermally insulated with a paint, polymer coating, hard anodizing or/and any thermal-insulation materials.

Cover plate made of a metal or non-metal may be used to secure diodes onto the cold plate to eliminate thermal stresses in between the cold plate and diodes.

Temperature sensors may be mounted on or embedded in the cold plate of the direct refrigeration cooling platform to provide temperature readings of the cold plate to a CPU of a feedback control system.

Execution of feedback control of the direct refrigeration cooling platform may be accomplished by detecting temperatures from sensors attached to the cold plate and then transmitting control signals to control the flow rate of refrigerant by RPM changes in the compressor or/and throttling up/down of the thermal expansion valve.

An operational temperature range of the cold plate may be in a range of −40° C. to 150° C. in the direct refrigeration cooling platform.

The cold plate may be rectangular, square, round, triangular, hexagonal or octagonal in shape. Edges and corners may be rounded off to reduce surface areas.

An outer surface of the cold plate may be plated, anodized or chem-filmed. Internal flow channels of the cold plate may have no finishes or/and have a plating on them.

The CPU in the direct refrigeration cooling platform may maintain the temperature of cold plate above the ambient temperature via feedback control. Alternatively or additionally, the CPU in the direct refrigeration cooling platform may maintain the temperature of cold plate at a user's preset temperature ±20° C. or less via feedback control.

The cold plate may be kept above the ambient temperature to prevent any dew point condensation. A fan may be utilized to blow air onto the cold plate as an additional condensation prevention.

LEDs may be centralized using the direct refrigeration cooling platform, and beams of light may be delivered to remote illumination areas via fiber optic light guides.

LED sources may be centralized with other types of cooling platforms such as a forced convection, water chiller and air conditioning cooling, and beams of light are delivered to remote illumination areas via fiber optic light guides.

The top of IC chips, where heat-sinking is normally performed, may be directly attached to the cold plate in the direct refrigeration cooling platform.

A direct refrigeration cooling platform with less than 500 W capacity may be used for a single illumination application, where it is not centralized, and may also be used for IC chip cooling.

The direct refrigeration cooling platform may be part of the vehicle refrigeration system, cooling vehicle LED headlights and other heat producing components in a vehicle.

With the direct refrigeration cooling platform with fiber optic light guides, change of LEDs in remote and hazardous locations such as a tunnel, bridge and nuclear power plant is not needed. The lifetime of LEDs is maximized due to a constant temperature maintained at the cold plate regardless of the ambient temperature and the amount of heat produced by LEDs.

With the direct refrigeration cooling platform with fiber optic light guides, automobile headlight LED sources may be cooled. The lifetime of LEDs is maximized due to a constant temperature maintained at the cold plate regardless of the ambient temperature and the amount of heat produced by LEDs.

With the direct refrigeration cooling platform with fiber optic light guides, the operation of drying inks on a paper printing may be faster because high power UV LEDs can be used. The lifetime of UV LEDs is maximized due to a constant temperature maintained at the cold plate regardless of the ambient temperature and the amount of heat produced by UV LEDs.

With the direct refrigeration cooling platform with fiber optic light guides, on-demand air/water sterilization with UVC-LEDs may be possible because high power UVC-LEDs can be used. The lifetime of UVC-LEDs is maximized due to a constant temperature maintained at the cold plate regardless of the ambient temperature and the amount of heat produced by UVC-LEDs.

With the direct refrigeration cooling platform, IC chips may be directly cooled by attaching the cold plate onto the top of an IC chip, where a heatsink is normally attached to. A constant temperature may be maintained at the cold plate regardless of the ambient temperature and the amount of heat produced by the IC chip.

Any heat producing components may be directly cooled by attaching the cold plate onto the component. A constant temperature may be maintained at the cold plate regardless of the ambient temperature and the amount of heat produced by the heat producing component.

Additional Notes

From the foregoing, it will be appreciated that various implementations of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various implementations disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

1. An apparatus, comprising:

a compressor capable of compressing a refrigerant;

a condenser capable of cooling and condensing the refrigerant;

a thermal expansion valve capable of evaporating at least a portion of the refrigerant;

a cold plate capable of receiving one or more heat sources for the one or more heat sources to be disposed on the cold plate; and

a tubing connecting the compressor, the condenser, the thermal expansion valve, and the cold plate such that the refrigerant undergoes a vapor compression refrigeration cycle as the refrigerant flows through the compressor, the condenser, the thermal expansion valve and the cold plate via the tubing,

wherein at least a portion of heat from the one or more heat sources is absorbed by the refrigerant via the cold plate.

2. The apparatus of claim 1, wherein the cold plate is made of a metallic material, and wherein the metallic material comprises aluminum or copper.

3. The apparatus of claim 1, wherein the cold plate is made of a non-metal material.

4. The apparatus of claim 3, wherein the non-metal material comprises silicon, beryllium oxide or aluminum nitride.

5. The apparatus of claim 1, wherein, when viewed from at least one angle, the cold plate is round, oval, elliptical or polygonal in shape.

6. The apparatus of claim 1, wherein an outer surface of the cold plate is plated, anodized or chem-filmed.

7. The apparatus of claim 1, wherein the cold plate comprises one or more internal flow channels therein for the refrigerant to flow through the cold plate in either a serial fashion or a parallel fashion.

8. The apparatus of claim 1, wherein a surface of the one or more internal flow channels of the cold plate has a plating thereon.

9. The apparatus of claim 1, wherein a surface of the cold plate exposed to an ambient is thermally insulated with paint, polymer coating, hard anodizing, or a thermal-insulation material.

10. The apparatus of claim 1, further comprising:

a temperature sensor disposed on or embedded in the cold plate, the temperature sensor capable of sensing a temperature of the cold plate and providing temperature data indicating the sensed temperature;

a first circuit associated with the compressor, the first circuit capable of detecting a rotational speed of the compressor and providing a first data indicating the detected rotational speed, the first circuit also capable of adjusting the rotational speed of the compressor in response to receiving a first control signal; and

a second circuit associated with the thermal expansion valve, the second circuit capable of detecting a position of the thermal expansion valve and providing a second data indicating the detected position, the second circuit also capable of adjusting the position of the thermal expansion valve in response to receiving a second control signal.

11. The apparatus of claim 10, further comprising:

a central processing unit (CPU) communicatively coupled to receive the temperature data, the first data, and the second data from the temperature sensor, the first circuit, and the second circuit, respectively, the CPU capable of controlling the temperature of cold plate by providing either or both of the first control signal and the second control signal to the first circuit and the second circuit, respectively.

12. The apparatus of claim 11, further comprising:

an ambient temperature sensor capable of sensing a temperature of an ambient in which the cold plate is situated,

wherein the CPU maintains the temperature of the cold plate above the sensed temperature of the ambient.

13. The apparatus of claim 11, wherein the CPU is capable of receiving a user input that sets a user-preset temperature, and wherein the CPU maintains the temperature of the cold plate within a range of ±20° C. from the user-preset temperature.

14. The apparatus of claim 11, wherein the CPU maintains the temperature of the cold plate within a range of −40° C. to 150° C.

15. The apparatus of claim 1, further comprising the one or more heat sources.

16. The apparatus of claim 15, wherein the one or more heat sources comprise at least a light emitting diode (LED), an integrated-circuit (IC) chip, an amplifier, or a laser diode.

17. The apparatus of claim 16, further comprising a fiber optic light guides coupled to the LED to guide at least a portion of a light emitted by the LED to a remote location.

18. The apparatus of claim 15, wherein the one or more heat sources are directly mounted onto the cold plate by one or more screws, one or more brackets, one or more springs, or a combination thereof.

19. The apparatus of claim 15, further comprising a cover plate that secures the one or more heat sources onto the cold plate.

20. The apparatus of claim 1, further comprising the refrigerant, wherein the refrigerant comprises R-134a, R-410A or R-407C.