Abstract
A preferred embodiment utilizes the waste heat from a refrigerant cycle to aid in the removal of condensate from a refrigerated case used primarily by grocery stores. Certain embodiments use a heating element to boil off condensate or a pump to remove the condensate. Another embodiment utilizes a wicking element and a shroud that directs hot air from the condenser through the wick thereby increasing the condensate evaporation rate. Yet another embodiment utilizes the hot gas tube from the refrigeration system routed through the bottom of the condensate tray to pre-heat the condensate to accelerate evaporation. Alternative embodiments combine certain features to create even more efficient system such as a heating element used with the wick system or the hot gas system used with the wick system. In some embodiments, a mold and mildew inhibitor is added to the condensate to maintain cleanliness.
Claims
1. A condensate removal system for a self-contained refrigerated case, comprising: a refrigeration system pan containing a fan; a condensate pan configured to collect condensate from the self-contained refrigerated case, wherein the condensate pan is located adjacent to the refrigeration system pan; an evaporative wick positioned in the condensate pan and comprising: a material having wicking properties, and horizontal airflow passages configured to allow air to flow through the evaporative wick, wherein the evaporative wick is located in the condensate pan such that a bottom of the evaporative wick comes into contact with the condensate collected by the condensate pan, wherein the fan is configured to cause the air to flow through the evaporative wick; and a shroud configured to duct the airflow generated by the fan to the evaporative wick.
2. The condensate removal system as recited in claim 1, wherein the material of the evaporative wick comprises a material selected from the group consisting of silica, polyester, and Teflon.
3. The condensate removal system as recited in claim 1, wherein the material of the evaporative wick comprises a material selected from the group consisting of rayon cellulose, cotton, and wool.
4. The condensate removal system as recited in claim 1, further comprising a heating element configured to kill mold, mildew, and bacteria in the condensate pan.
5. The condensate removal system as recited in claim 1, further comprising a dispenser and a dispenser tube, the dispenser and the dispenser tube configured to add a mold and mildew inhibitor solution to the condensate collected in the condensate pan.
6. The condensate removal system as recited in claim 1, further comprising heating means to heat the condensate collected in the condensate pan.
7. The condensate removal system as recited in claim 6, wherein the heating means comprises a heating element.
8. The condensate removal system as recited in claim 6, wherein the heating means comprises a hot gas tube configured to direct waste heat through the condensate pan.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:
(2) FIG. 1 is a perspective view of the front of a portable and self-contained refrigerated display case;
(3) FIG. 2 is a perspective view of the rear of a portable and self-contained refrigerated display case showing the refrigeration unit;
(4) FIG. 3 is a perspective view of the front of a double wide portable and self-contained refrigerated display case;
(5) FIG. 4 is a perspective view of two refrigerated display cases oriented back to back having a spacer between the units to allow for moisture and heat removal;
(6) FIG. 5 is a schematic view of a refrigeration system the utilizes a high-volume pump to remove condensate;
(7) FIG. 6 is a schematic view of a refrigeration system that utilizes a heating element to boil off condensate that collects in the condensate tray;
(8) FIG. 7 is a schematic view of a refrigeration system that utilizes a heating element, a wicking element, and a shroud that directs air flow from the condenser through the wicking element to evaporate condensate;
(9) FIG. 8 is a schematic view of a refrigeration system that utilizes the hot gas portion of the refrigerant system that pre-heats the condensate to aid in condensate removal;
(10) FIG. 9 is a top schematic view of a refrigerator case showing the airflow path through the case to allow for accelerated evaporation of condensate buildup;
(11) FIG. 10 is a schematic view of multiple refrigeration systems connected to a central control and monitoring system;
(12) FIG. 11 is a schematic view of refrigeration systems that utilize hardwired and wireless networking to connect the refrigeration systems to the control and monitoring system; and
(13) FIG. 12 is a schematic view of multiple control and monitoring systems connected to the internet/cloud, where each control and monitoring system has multiple refrigerated display cases connected to it through a local network and a remote operator able to connect using a remote terminal.
DETAILED DESCRIPTION
(14) Referring initially to FIG. 1, a perspective view of the front of a portable and self-contained refrigerated display case is shown and referred to as 10. Refrigerated case 10 has a refrigerated space 14 that is cooled by the refrigeration system 20 (not shown, see FIG. 2). Located on the front of the refrigerated case 10 is air inlet cover 12 that allows cool air to enter the interior of the refrigerated case 10 to cool the refrigeration system 20. Air inlet cover 12 may also consist of air filters to prevent dirt and dust from entering the interior of refrigerated case 10, which may reduce air flow through the system thereby reducing efficiency and increasing total power usage.
(15) Referring now to FIG. 2, a perspective view of the rear of refrigerated case 10 is shown. Located at the rear of refrigerated case 10 are power cord 18, air outlet 16, and refrigeration system 20. Power cord 18 may be configured to connect to various power systems, such as systems that supply power at 110 volts or 220 volts. It is to be appreciated by someone skilled in the art that refrigerated case 10 may be connected to most single phase power systems. Air outlet cover 24 (not shown) covers air outlet 16 and allows air flow generated by refrigeration system 20 to exit the interior of refrigerated case 10 to remove heat and humidity. When installed, air outlet cover helps to direct air flow through refrigeration system 20 such that the air flow assists in removing condensate and waste heat. Refrigeration system 20 will be discussed in more detail below.
(16) FIG. 3 is a perspective view of the front of a double wide portable and self-contained refrigerated display case and referred to as 30. Similar to refrigerated case 10, refrigerated case 30 consists of air inlet cover 32 and refrigerated space 34. Similar to air inlet cover 12, air inlet cover 32 may also consist of air filters to remove dust and dirt from the air that enters the interior of refrigerated case 30 for waste heat and condensate removal.
(17) FIG. 4 is a perspective view of two refrigerated cases 10 positioned back to back. Spacer 22 is a component that prevents the backs of the refrigeration cases from coming into contact with each other, thereby providing an air gap to allow waste heat and evaporated condensate from the refrigeration cases 10 to discharge into the ambient environment. A similar spacer may be used with doublewide refrigeration cases when placed back to back.
(18) FIG. 5 is a schematic view of a refrigeration system that utilizes a high-volume pump to remove condensate and is referred to as 40. Refrigeration system 40 consists of a condenser 41, a fan 42, a compressor 44, an accumulator 46, a controller 48, a pan 50, a condensate tray 52, a high volume pump 54, a discharge hose 56, and a condensate drain 58. Condenser 41, fan 42, compressor 44, accumulator 436, and controller 48 function using a typical refrigeration cycle. Compressor 44 forces hot gas into condenser 41, which fan 42 moves air through to remove heat. Condenser 41 allows the hot gas to condense into a high-pressure hot liquid that is then pumped through an expansion valve where the pressure and temperature of the hot liquid is reduced. The low-pressure liquid then moves through the evaporator where it expands back into a low pressure gas thereby causing the temperature of the gas to decrease as a result of the gas expansion. The hot low pressure gas then flows to the accumulator then to the compressor where it becomes a high pressure gas ready to flow in the condenser where it returns to being a high pressure liquid and the refrigeration cycle repeats itself. Controller 48 controls the overall operation of refrigerated cases 10 and 30, including the operation of compressor 44, fan 42, and any heating elements 62 (see FIG. 6). Controller 48 may also allow multiple refrigerated cases to be networked together to allow a central monitoring and control system (see FIGS. 10-12) to monitor and control the operation of the individual cases. Some embodiments of the present invention may, for instance, implement a level sensor 63 (see FIG. 7) in condensate tray 52. If the level of condensate exceeds a predetermined level, a local maintenance light (not shown) and an audible indicator may be activated as well as the central system is notified so maintenance may be performed on the refrigerated case. Other information may be reported to the central system such as local system status, power usage, and temperatures. Other embodiments may include Wi-Fi technology (see FIGS. 11-12) to allow networking of the refrigerated cases without the need to install network cables throughout the space.
(19) High volume pump 54 is used to pump condensate from the condensate tray 52. Condensate is produced by the evaporator coil located in refrigerated spaces 14 and 34. The condensate typically drips off the coils of the evaporator where it is collected and directed to condensate tray 52 through condensate drain 58. During normal operation in a high humidity location or a floral refrigeration system, the amount of condensate produced may exceed traditional methods of condensate removal, such as boiling off the condensate using a heating element. The failure to remove all produced condensate results in ongoing and routine maintenance that removes the collected condensate and may lead to the formation of mold and mildew. The use of high volume pump 54 allows the use of flexible hose or tubing 56 to direct the condensate out of refrigerated cases 10 and 30 to a location having a drain. Pump 54 provides sufficient output pressure that the condensate can be pumped up to a height above the refrigeration case then horizontally to an appropriate drain location. Since flexible hose or tubing 56 is used, the hose or tubing 56 may be routed as necessary to reach the drain location. Such an implementation allows refrigerated cases 10 and 30 to be placed a various locations in a store without the need to consider where to drain the condensate since the hose or tubing 56 is flexible and may be routed as necessary. In an alternative embodiment, refrigeration system 40 may also consist of a heating element 62 (not shown, see FIG. 6) to aid in condensate removal as well as to heat the condensate on a periodic basis to help kill or reduce mold and mildew.
(20) Referring now to FIG. 6, a schematic view of a refrigeration system utilizing a heating element to remove condensate is shown and referred to as 80. Refrigeration system 80, similar to refrigeration system 40, consists of a condenser 41, a fan 42, a compressor 44, an accumulator 46, a controller 48, a pan 50, a condensate tray 52, a heat controller 60, a heating element 62, and a condensate drain 58. Some embodiments may use a shroud 68 (see FIG. 7) to direct airflow through the refrigerated cases 10 and 30. The operation of refrigeration system 80 is similar to refrigeration system 40 except for the method of condensate removal. In operation, refrigeration system 80 will run for an extended period of time to cool refrigerated spaces 14 and 34. After running for the extended period of time, compressor 44 and fan 42 will turn off thereby reducing power demand. Next, heat controller 60 energizes heating element 62 to boil off any condensate that has accumulated in condensate tray 52. The amount of time that heating element 62 is energized depends on the ambient temperature and the amount of condensate that has collected in condensate tray 52. In some embodiments of the present invention, a liquid level sensor 63 (not shown, see FIG. 7) is utilized to determine proper timing for the cooling and defrost cycles. Since the items located in refrigerated spaces 14 and 34 must be kept at a certain temperature, the amount of time available to operate heating element 62 may be limited. As such, heating element 62 may be powerful enough that additional power connections or higher input voltages to the refrigerated cases 10 and 30 may be necessary. However, the use of more powerful heaters may result in the total power consumed by the systems to exceed power efficiency guidelines.
(21) FIG. 7 is a schematic view of a preferred embodiment refrigeration system of the present invention and referred to as 90. Refrigeration system 90 consists of a condenser 41, a fan 42, a compressor 44, an accumulator 46, a controller 48, a pan 50, a condensate tray 52, a heat controller 60, a heating element 62, a level sensor 63, an evaporative wick 64, a shroud 68, and a condensate drain 58. Wick 64 is located in condensate pan 52 such that the bottom of wick 64 comes into contact with condensate that collects in condensate pan 52. Due to the wicking action of wick 64, condensate wicks up into the structure of wick 64. Wick 64 is designed with horizontal airflow passages 65 that allow air to flow through the structure of wick 64. During operation of a typical refrigeration cycle, an appreciable amount of waste heat is generated, particularly in the condenser 41.
(22) To aid in condensate removal, the airflow generated by fan 42 is ducted by shroud 68 through condenser 41 to wick 64, where the air passes through airflow passages 65 which run horizontally through wick 64. The airflow through airflow passages 65 of wick 64 evaporates condensate absorbed by wick 64. In a preferred embodiment, the wick 64 may be made by any material known in the art to exhibit wicking properties including capillary action, including but not limited to silica, polyester, Teflon, and other synthetic materials. Also, many natural materials, such as rayon cellulose, cotton and wool, are suitable materials for acceptable wicking properties for the present invention. Wick 64 includes air passages which run horizontally through the body of the wick 64 to facilitate the exposure of the wetted wicking material to the air as it passes through the wick 64. The particular size and shape of the wick passages 65 as shown in FIG. 7 are merely exemplary. It is to be appreciated that the specific size, shape, and configuration of the wick passages 65 are merely exemplary, and are in no way intended to limit the scope of the invention. Rather, all wicking materials and configurations known in the art are fully contemplated herein. While it is advantageous to provide a wick 64 having distinct passages 65, it is also contemplated that wick 64 may be formed with a variable mesh configuration in which there is no clearly formed passage through the wick 64, yet air passes through at least a portion of it.
(23) The increased temperature of the airflow, resulting from the heat given off by condenser 41, increases the rate of condensate evaporation. After the airflow exits wick 64, the airflow exits the rear of refrigerated cases 10 and 30 through air outlet 16 in air outlet cover 24. In certain embodiments of the present invention, air outlet cover 24 provides a portion of shroud 68 to direct airflow to wick 64. This design also allows for quicker and easier access to the refrigeration components during maintenance. Fan 42 may be configured to operate when compressor 44 is deactivated, thereby allowing fan 42 to continue generating air flow through wick 64 to continue removing condensate.
(24) Refrigeration system 90, similar to refrigeration system 80, utilizes heat controller 60, level sensor 63, and heating element 62. Heating element 62 can be used to supplement the condensate removal effect of wick 64. Heating element 62 also aids in the prevention of mold and mildew by periodically energizing heating element 62 to raise the temperature of any standing condensate in condensate tray 52 to an appropriate level to kill mold, mildew, and any other bacteria that may exist in the condensate. Since refrigeration system 90 utilizes waste heat to aid in the removal of condensate, the amount of time and power used by heating element 62 is greatly reduced thereby reducing the overall amount of power consumed by refrigeration system 90. Further, since the overall power requirements are reduced, standard power connections may be used to operate the systems without the need for additional power connections or high voltage connections. Such power reductions allow refrigerated cases 10 and 30 to operate within established guidelines for power consumption and efficiency.
(25) In certain embodiments of the present invention, a dispenser 66 and dispenser tube 67 are utilized to allow for the addition of a mold and mildew inhibitor solution to the condensate. Since wick 64 will also absorb the inhibitor solution along with the condensate, mold and mildew will also be prevented within the structure of wick 64. As discussed above, heating element 62 may also be energized on a periodic basis, or as needed, to aid in the prevention of mold and mildew in condensate tray 52 and wick 64. The prevention of mold and mildew is especially critical in the grocery business due to the offensive nature of the odors produced by molds and mildews. Since refrigerated cases 10 and 30 take in and expel air, any mold or mildew smells generated within the cases 10 and 30 will be spread throughout the store.
(26) FIG. 8 is a schematic view of a refrigeration system that utilizes the hot gas portion of the refrigerant cycle to aid in the removal of condensate and is referred to as 100. Refrigeration system 100 consists of a condenser 41, a fan 42, a compressor 44, an accumulator 46, a controller 48, a pan 50, a condensate tray 52, a heat controller 60, a heating element 62, and a condensate drain 58. As discussed above, in a refrigerant cycle, hot high-pressure gas is created by compressor 44. Typically, the heat from the hot high-pressure gas is transferred to the ambient air as waste heat through the condenser 41. In this embodiment of the present invention, hot gas tube 70 is routed such that it makes one or more loops in the bottom of condensate tray 52. Certain embodiments may contain condensate trays having multiple levels so that hot gas tube 70 makes multiple loops through each level of the condensate tray thereby increasing the efficiency of the system since more heat will be transferred from hot gas tube 70 to the condensate.
(27) In operation, any condensate that collects in condensate tray 52 through condensate drain 58 is heated by the waste heat transferred from hot gas tube 70, thereby increasing the rate of evaporation. Since hot gas is generated at all times during operation of compressor 44, waste heat is continually transferred to any condensate accumulated in condensate tray 52. As a result, the amount of time required for heating element 62 to operate is reduced, if not eliminated. This use of waste heat to evaporate condensate and reduced run time for heating element 62 allows refrigerated cases 10 and 30 to operate within prescribed energy consumption limits.
(28) Also shown in FIG. 8, are early leak detection system and a moisture sensing system. Early leak detection system comprises an early leak detector (ELD) 72, which comprises at least one level sensor positioned in the condensate tray 52. If a multilevel condensate tray is used, the ELD 72 is located in the bottom most level. In contrast to the operation of level sensor 63 (see FIG. 7), ELD 72 is configured to sense condensate level at or near the top of the condensate tray. In normal operation, level sensor 63 controls the timing for the cooling and defrost cycles. The main purpose of ELD 72 is to sense condensate level near the top of condensate tray 52. Due to the desire to avoid slip and fall type accidents, ELD 72 is configured to cause refrigeration system 100 to shutdown thereby stopping the creation of condensate. If the condensate level reaches a predetermined level, ELD 72 sends a signal to refrigeration system 100, which in response turns off the compressor 44 and fan 42. Certain embodiments of the present invention has the refrigeration system 100 only turning off compressor 44 while leaving fan 42 energized to assist in the reduction of condensate level in condensate tray 52 in response to a signal from the ELD 72. It is to be appreciated by someone skilled in the art that ELD 72 may be used in other embodiments of the present invention.
(29) Also shown in FIG. 8, is moisture sensor 74. Moisture sensor 74 is located at a low point in refrigerated cases 10 and 30 where water or moisture is likely to accumulate. In a preferred embodiment, moisture sensor 74 is located below condensate tray 52. However, alternative embodiments of the present invention may have moisture sensor 74 located away from refrigeration system 100.
(30) Moisture sensor 74 is configured to sense the present of moisture, not just the presence of standing liquid. Since moisture sensor 74 is located outside of condensate tray 52, it should not sense the presence of any moisture. However, due to differing operating conditions, moisture sensor 74 may be configured to sense some moisture without generating an alarm condition.
(31) The presence of moisture inside refrigerated cases 10 and 30 may lead to the formation of mold and mildew, which typically produces an offensive odor. Moisture sensor 74 provides an indication that moisture has formed outside of refrigeration system 100, which may be due to an overflow condition of condensate tray 52 or a leak from another portion of refrigerated cases 10 and 30.
(32) Referring now to FIG. 9, shown is a top schematic view of the interior of a refrigerator case showing the airflow path through the refrigerator case. As shown, refrigerated case 10 contains refrigeration system 20, divider wall 28, air inlet cover 12, air outlet cover 24, and rear panel 26. Refrigeration system 20 consists of Condenser 41, fan 42, compressor 44, accumulator 46, and controller 48 located in pan 50. Also contained in refrigeration system 20 are condensate tray 52, heater controller 60, heater 62, and wick 64. It is to be appreciated by someone skilled in the art that the refrigeration systems described in FIGS. 5, 6, 7, and 8 may be used for refrigeration system 20 without departing from the scope and spirit of the present invention.
(33) As shown in FIG. 9, airflow 82 enters the front of refrigerated case 10 through air inlet cover 12. The presence of divider wall 28 causes airflow 82 to divert around the divider wall 28 and enter the condenser 41 of refrigeration system 20. Airflow 82 then passes through the refrigeration system 20, where the airflow 82 removes heat created in a refrigeration cycle and aids in the removal of condensate that accumulates in condensate pan 52. A shroud, such as shroud 68 (not shown, see FIG. 7) may be used to further aid in the control of airflow 82. Airflow 82 then exits the refrigerated case 10 through air outlet cover 24. Rear panel 26 is a solid panel and does not let airflow 82 pass through it. Rear panel 26 allows for easy access to the portion of refrigeration system 20 contained in pan 50. During use, a system operator must install rear panel 26 to allow airflow 82 to properly move through refrigeration system 20.
(34) It is to be appreciated by someone skilled in the art that different styles of refrigerated cases, such as double refrigerated case 30 (see FIG. 3), may be used alone or in conjunction with refrigerated cases 10 without departing from the scope and spirit of the present invention.
(35) Referring now to FIG. 10, a system of refrigerated cases connected to a local control and monitoring system is shown and generally designated 200. System 200 comprises multiple refrigerated cases 10 connected to a local control and monitoring server 202 through local network 206. Server 202 may have an Internet connection 204. Local network 206 connects to controller 48 (see FIGS. 5-8). Controller 48 is configured to communicate refrigerated case's 10 operational and status information to, as well as receive operational commands from, server 202. Server 202 is configured to receive information from each refrigerated case 10 and generate appropriate commands or notifications in response to the received information. For example, refrigerated case 10 may report to server 202 that the temperature of the refrigerated space 14 is too high to properly maintain the temperature of any items located in the space 14. Server 202 may then send a command signal to refrigerated case 10 to decrease its temperature setting. Alternatively, refrigerated case 10 may report to server 202 that condensate pan 52 is full and requires attention. Server 202 may then issue a notification about the condition of refrigerated case 10 to the appropriate person. Refrigerated case 10 may also report to server 202 the removal and replacement of covers 12, 24, and 26, and condensate tray 52.
(36) FIG. 11 is a schematic view of a system of refrigerated cases connected to a local control and monitoring server through a hybrid wired and wireless local network and generally designated 300. System 300 comprises multiple refrigerated cases 10, a local control and monitoring server 308, a local network 302, a router/switch 304, a wireless access point 306, and a connection to the Internet 312. As shown in FIG. 11, certain refrigerated cases 10 contain wireless transceivers 310, which are configured to communicate with wireless access point 306. Wireless access point 306 in turn communicates with server 308 through local network 302. Other refrigerated cases 10 are connected to local network 302 through hardwired connections. Local network 302 also connects to router/switch 304 to allow for external communications regarding the operational status of system 300.
(37) In operation, refrigerated cases 10 communicate with local server to transmit case status as well as receive operational commands, similar to system 200 discussed above. Refrigerated cases 10 having the wireless transceiver 310 allow for easier placement of refrigerated cases 10 without the need to use a hardwire connection to local network 302. An operator may interface with server 308 to program temperature set points for each refrigerated case 10 collectively, individually, or in sub-groups.
(38) Moving now to FIG. 12, a schematic view of a system containing multiple control and monitoring systems connected to the internet/cloud is shown and generally designated 400. System 400 contains multiple local control and monitoring servers 410, with each server hosting refrigerated cases 10 connected through local network 412. It is to be appreciated by someone skilled in the art that refrigerated cases 10 and local network 412 may be the systems 200 and 300 described in FIGS. 10 and 11. However, other network topologies are fully contemplated.
(39) Each server 410 connects to the internet/cloud 402 through communication link 408, which may be any type of connection including WAN, cellular, Ethernet, Frame Relay, Fiber Optic, or any other communication protocol known in the industry. Also connected to internet cloud 402 is remote computer 404, which connects to internet/cloud 402 through a communication link 406, which is any communication protocol known in the industry, similar to servers 410. An operator of remote computer 404 accesses each server 410 through internet/cloud 402 to receive status information and send operational commands, such as raising and lowering temperature set points for each refrigerated case 10.
(40) Alternatively, a remote control and monitoring server 414 (shown in dashed lines) may be located in the internet/cloud 402, which communicates directly with local servers 410. In this configuration, remote server continually communicates with local servers 410 to send and receive status information and operational commands. The remote computer 404 then connects with remote server 414 to monitor status information and adjust desired set points or other features of system 400. In this alternative configuration, remote computer 404 may also connect directly to each local server 410 to send and receive status information and operational commands.
(41) Local networks 206, 302, and 412 may be any type of networking topology known in the industry, such as Ethernet, RS232/422/485, wireless, or other point-to-point or multi-drop technology.
(42) It is to be appreciated by someone skilled in the art that various portions of the various embodiments described above may be combined to create a more efficient system. For example but without limitation, refrigeration system 100 may also incorporate wick 64 and shroud 68 to create a system capable of operation in a high temperature and high humidity environment without the need for additional power connections, drains, or the routing of tubing through the grocery space. Another example is dispenser 66 and dispenser tube 67 may be used with refrigeration systems 40, 80, and 100 without departing from the scope and spirit of the present invention. Further, since the above discussed systems are designed to remove condensate at an increased rate, maintenance requirements are minimized since accumulated condensate will not need to be removed manually.
(43) While there have been shown what are presently considered to be preferred embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the scope and spirit of the invention.
