Abstract:
An environmental controlling system to better preserve cut flowers and other flora in vase water. The system uses thermoelectric modules, heat exchangers, fans, power supply, and a thermal conductor to cool and/or heat the water in a flower vase as required. By cooling the water, formation of algae and formation of a callus on the cut stem is reduced. In addition, keeping the stems in water of optimal temperature controls production of ethylene and other phytohormones. These effects prevent premature wilting, leaf abscission, flower senescence, and reduces the care required to maximize the life of cut flowers and other flora. In the event of cold ambient conditions that might cause freezing, the flow of heat can optionally be reversed, warming the water in the vase to avoid freezing the stems and/or maintain optimum temperature and other conditions for a specific variety of flora.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This is the regular utility filing of provisional patent application 61/687,972, filed May 4, 2012, titled “Vase Environmental Conditioning Device” by the same inventors. 
     REFERENCE TO FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     NA 
     REFERENCE TO JOINT RESEARCH AGREEMENTS 
     NA 
     REFERENCE TO SEQUENCE LISTING 
     NA 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to methods and apparatus for preserving plants after cutting, and, in particular, relates to preserving cut flowers and flora in a container, and, in greater particularity, relates to cooling and/or heating the water in a vase or other container that is used to hold cut flowers and other flora. 
     2. Description of the Prior Art 
     Cut flowers such as roses and other flora are frequently used to enhance the aesthetics and health of an environment and as a gift of endearment and appreciation. The lifetime of such often expensive cut flora is limited by the ability of the cut stem to draw water up to the petals, leaves, etc., by the growth of algae that can plug the transport cells in the xylem and the growth of a callus by the flora itself that seals off the cut end of the stem in an undesired attempt to heal itself. 
     In addition the phloem needs to be free to transport liquid down through the stem for the proper functioning of the cells in the flora. 
     In order to deal with the effects of algae and growth of a callus, it is standard practice to change the water in a vase every second day and recut the end of the stem to remove the callus and algae. Unfortunately, this procedure is time consuming, and many people either do not know of this procedure or forget to do it or are unaware of how best to extend the life of cut flora. In addition, each time the stem is cut the flora becomes shorter reducing its aesthetic value. 
     The importance of control of phytohormones should not be underestimated. For example, roses are popular as cut flowers partly as they are dicots, dicots being generally less affected by auxins than monocots. But all flora are not equally affected such as lilies, being monocots, are generally even more deleteriously affected by auxins than roses, thus the conventional practice of preservation has not been commercially practical. 
     Flower shops typically keep flowers in a cooler, cooling the entire flower to prolong their life, but once sold to the consumer, the flower immediately starts to deteriorate. 
     Other products currently exist that are sold to enhance the lifetime of cut flora. Some products are marketed as “plant food” or “plant preservatives”. One such “plant food” is actually the chemical, alum (aluminum magnesium sulfate). Alum acidifies the water in the vase in an attempt to retard the growth of algae. Unfortunately this approach has limited value and in some cases is deleterious to the flora. Other products use algaecides or metal ions that are toxic to algae in an attempt to limit or retard algae growth. Here again these products are often undesirable, perform poorly, and can actually damage the flora. 
     Several patents disclose different chemical compositions and processes to preserve cut flows: U.S. Pat. Nos. 8,263,528; 8,250,805; 7,273,831; 7,199,082; 6,688,039; 6,440,900; 6,365,548; 5,500,403; and 4,061,483. These patents are incorporated by reference. 
     Accordingly, there is a need for a device and method for preserving cut flowers and flora and other plants without the use of chemicals. 
     SUMMARY OF THE INVENTION 
     The present invention provides a device for extending the useful life of cut plants, and in particular, cut flowers and flora by the use of a temperature controlling device. 
     The temperature controlling device has one or more thermoelectric modules or cooling/heating devices attached to one or more heat sinks and cold plates. When the correct power is applied to a thermoelectric module or cooling/heating device, heat flows from the “cold” side of the thermoelectric module or cooling device to the “hot” side of the module where heat sinks are located. In the case of the thermoelectric device, this is called the Peltier Effect. The hot side of the module is placed in thermal contact with a heat sink. The heat sink absorbs and distributes the heat into itself, and typically through its fins to exchange the heat to the ambient air. To enhance that transfer of heat to the ambient air, a fan can be used to circulate the air maximizing heat transfer. Use of a fan can reduce the size of the heat sink required and minimize reheating of the vase by preventing the warmed air from coming into contact with the vase. 
     The cold side of the thermoelectric module is placed in contact with a thermally conductive cold plate. This plate is brought into thermal contact with the vase in a manner that facilitates transfer of heat from/to the water in the vase. 
     Since the cold plate is in thermal contact with the cold side of the thermoelectric module this heat from the water of the vase is transferred to the heat sink and in turn to the ambient air. 
     The vase can be placed on the cold plate directly if the vase is composed of a good thermal conductor such as a metal. If the vase is composed of a poor thermal conductor such as glass, ceramic, or plastic, it is desirable then to enhance the thermal conduction of heat from the water to the cold plate by adding a thermal conductor. The thermal conductor can extend from near the surface of the water in the vase to the cold plate underneath the vase. If the vase is sitting on the cold plate the thermal conductor can extend through a hole in the bottom of the vase and have a large enough diameter where it contacts the cold plate to efficiently transfer heat from the water in the vase into the cold plate and vice versa. 
     Alternatively, if desired, a modified thermal conductor can be placed in thermal contact with the upper section of the water in the vase. The advantage to this approach is that a thermal conductor may not be required extending through the center of the vase as the cold water produced by the device will cause convection directly. If the vase is built of a thermally conductive material such as metal the device can be brought into thermal contact virtually anywhere in or on the vase. 
     If the vase is composed of a transparent material such as glass or plastic it can generally be more aesthetically desirable to place the cold plate under the vase and use a thermal conductor that extends up through the center of the vase to near the surface of the water to cause efficient transfer of heat from the water in the vase by conduction and convection, cooling or heating the water from the inside out, minimizing thermal load. 
     In addition, it can be desirable to use a vase composed of a poor thermal conductor, such as glass, ceramic, or plastic to minimize the heat gain from the ambient air. If the surface of the vase is closer to the ambient temperature due to the poor thermal conductivity of the walls of the vase, less heat will flow into the water putting less burden on the cooling device allowing the device to be smaller, consume less energy, and will cause less condensation on the exterior of the vase. In this case the thermal conductor is required if the cooling device is located underneath the vase. If the thermal contact is made by placing the temperature controlling device at, in, or near the top surface of the water in the vase an additional thermal conductor may not be required. 
     As an alternative, the water in the vase can be circulated out of the vase through the cold plate attached to the thermoelectric device or other heat/cool device and back to the vase. This is generally less desirable aesthetically and functionally, but can be desirable for use in larger vases as the larger apparatus required can be remotely located out of sight. It also can facilitate larger cooling devices such as conventional gas compression or absorption cooling devices as well as provide a means to add water to the vase as needed. 
     As another alternative, the cold plate can be liquid cooled or heated and the heat transferred to or from the cold plate by circulating the liquid to a remote heat exchanger or cooling device. 
     It is therefore one aspect of the present invention to provide an attractive, compact device based on a thermoelectric cooler or other cool/heat device so that the aesthetic aspects of cut flowers can be maintained and the useful life of such flora can be maximized. 
     It is another aspect of the present invention to provide a temperature control device for a vase having no maintenance beyond the periodic addition of water to replenish the water lost to transpiration by the flora and evaporation. In fact the evaporation of water is reduced by the lowering of the temperature of the water in the vase by the temperature control device. 
     It is another aspect of the present invention to provide a method of extending the useful life of cut plants, and flowers in particular that does not use any chemicals in the water and/or preservatives. 
     It is another aspect of the present invention to provide a method and a temperature cooling device that eliminates or greatly reduces algae growth and the growth of a callus on the cut end of a stem. 
     It is a further aspect of the present invention to provide a device that adjusts the voltage and power applied to the thermoelectric module to maintain the temperature of the water in the vase at an optimal performance level. 
     In another aspect of the present invention wherein the temperature controlling device adjusts the voltage and power applied to a fan or fans to control the amount of heat transferred and thus the temperature of the water in the vase is maintained at an optimum operating temperature. 
     In another aspect of the present invention, the flow of heat is reversed in order to heat the water to avoid freezing and damaging the stems of the flowers by reversing the polarity of voltage applied to the module. 
     In another aspect of the present invention, the temperature controlling device will make monocots commercially practical as cut flowers, greatly expanding the aesthetic possibilities. 
     In another aspect of the present invention, an LED indicator is used to verify the proper functioning and/or temperature of the device. 
     In another aspect of the present invention, a thermal switch or switches can be used to control the temperature controlling device having the thermoelectric device therein and/or the fan to obtain the desired water temperature in the vase. 
     In another aspect of the present invention, a micro-controller is used to sense the temperature of the device and/or the vase water with a thermistor, thermocouple, or other temperature sensing device in order to control the cooling or heating applied to the vase water in conjunction with the thermoelectric module and/or fan. In addition, the micro-controller can verify proper operation of the device and indicate the condition by illuminating one or more LEDs. 
     These and other objects, features, and advantages of the present invention will become more readily apparent from the attached drawings and the detailed description of the preferred embodiments, which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevation cross-section of the temperature controlling device with a glass vase and thermal conductor within the vase; 
         FIG. 2  is a side elevation cross-section of the temperature controlling device with a metallic vase and insulated cup inside the bottom of the vase; 
         FIG. 3A  is a block diagram of a preferred embodiment of the present invention;  FIG. 3B  illustrates a generic temperature controlling system; and 
         FIG. 4  is a block flow diagram of the present invention having a programmable processor therein. 
     
    
    
     Like reference numerals refer to like parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention provides a device for extending the useful life of cut plants, and in particular, cut flowers and flora by the use of a temperature controlling device that appropriately adjusts the water temperature. 
     Even the standard practice cited above does not extend the life of many flora as compared to the present invention. In addition to controlling algae and callus growth, cooling the stems in the water reduces the production and transport of ethylene, auxins, and other phytohormones, as well as accumulation of such phytohormones in the vase water. Ethylene is a plant hormone that accelerates ripening and deterioration of many plants and fruit. Ethylene is generally recognized as causing deterioration of flowers if they do not receive adequate air ventilation. By preventing generation and accumulation of ethylene in the vase water, deterioration of flowers is delayed. The effect of reduction of auxins can also be observed as cooling the stems stimulates new growth of shoots on the stems and retards callus formation where the stem has been cut. The reason for the preference for new growth of shoots at the expense of callus or root formation is the reduced ratio of auxin to cytokinin. 
     Referring now to  FIG. 1 , a temperature controlling system  100  has a vase cooling device  1  with a housing  2  that defines an open chamber  3  in which a heat sink  4  and a thermoelectric module  5  is disposed. The thermoelectric module operates as a Peltier device. The overall dimensions of housing  2  may vary greatly not only in terms of size but also shape and may be ornamental in nature. A number of configurations are suitable for heat sink  4 . The configuration shown for heat sink  4  is composed of a metal plate  6  having multiple fins  7 . In general, multiple fins  7  fixed in the conventional manner optimize heat transfer from the thermoelectric module  5  in the preferred embodiment, but other heat dissipation means or configurations may be suitable. 
     The hot side of the thermoelectric module  5  is typically in thermal contact with heat sink  4  and a cold side of thermoelectric module  5  is typically in thermal contact with a cold plate  8 . Cold plate  8  is in contact with the vase  10  or other container. By reversing the polarity of the power applied to the thermoelectric module  5  with an electronic controller  9 , the direction of heat flow effected by thermoelectric module  5  can be reversed to warm the vase  10  and avoid freezing of the cut stems of flora  11  in the event the vase becomes too cold as in the occurrence of cold weather. 
     Heat sink  4  and cold plate  8  are typically formed of metal that is an excellent heat conductor. Most preferred are copper or aluminum or the like. The surface ratio of heat sink  4  to cold plate  8 , the thermal characteristics of the materials used to form heat sink  4  and cold plate  8 , the characteristics of thermoelectric module  5 , as well as the air velocity and flow over heat sink  4  are such that the cold plate  8  is maintained at an appropriate temperature so as to maintain the desired temperature of the water in vase  10 , typically about a few degrees above zero degrees C. Typically the thermal resistance between heat sink  4  and cold plate  8  will be well below 2 degrees Celsius per Watt. Cold plate  8  will typically have a surface area of 0.5 to 50 square inches or more. It will be appreciated that heat sink  4  and cold plate  8  will be attached to thermoelectric module  5  in the standard way known to those skilled in the art. 
     A fan or fans  14  are shown below heat sink  4  to circulate ambient air through heat sink  4  to increase the cooling efficiency of heat sink  4 . Appropriate vents in the housing  2  would be included as necessary. The fan or fans  14  can be configured in a number of ways known in the art. The configuration shown is preferred for the purpose of compactness and high efficiency. The use of two fans  14  allows placement of the fans such that the highest velocity air at the periphery of each fan  14  is introduced directly under the center of cold plate  8 , and in turn, directly under the center of thermal conductor  15 . This minimizes the thermal path. In addition, locating the fans  14  directly at the bottom of heat sink  4  and fins  7  improves heat transfer efficiency by inducing vortices into the spaces between fins  7  due to rotation of the blades in fans  14  and aerodynamic shear directly over fins  7 . This reduces the thickness of the boundary layer of air that typically insulates the surface of fins  7  of heat sink  4 . 
     Cold plate  8 , housing  2 , heat sink  4 , and insulating layer  12  may contain one or more small holes or paths to allow condensed water from vase  10 , cold plate  8 , and thermoelectric module  5  to flow into the area of heat sink fins  7  in order to increase the cooling effect obtained and dispose of the condensate. 
     Thermoelectric module  5  is surrounded by insulation layer  12  to seal out moisture and minimize undesired heat flow between heat sink  4  and cold plate  8 . 
     In some applications requiring a large heat transfer area and/or high thermal capacity, it may be desirable to utilize more than one thermoelectric module per heat sink and/or cold plate, as well as multiple heat sinks and/or cold plates. When multiple thermoelectric modules are utilized, it is often useful to wire the modules in series. 
     A micro-controller  13  is preferably provided for careful regulation of the temperature of vase  10  as well as controlling and monitoring of proper functions as noted herein and performance of the device. Micro-controller  13  using appropriate sensors can track temperatures, humidities, dew points, moisture, light levels, other atmospheric conditions, electrical conditions, perform diagnostics, vary operation by time of day, control LED lights and lighting, communicate with other electronic devices, and log the operation of the device. As to operational condition of the system, a thermochromic or other visible temperature indicator utilizing liquid crystals, leuco dyes, or other means indicates by a change in color, transparency, or other means that the system is operating properly. For example, microencapsulated dyes can be embedded, printed, laminated, etc., in or on the vase, housing, or cold plate, the color, transparency, or other appearance of which would indicate the operating temperature of the water in the vase or the system. The color, for example, may change continuously over a predetermined range. 
     In conjunction with the real time clock, the micro-controller  13  can control the operation of the device  1  as to time of day, by the calendar day, and by the season as well as in conjunction with natural light and artificial illumination requirements. 
     The vase can be placed on the cold plate  8  directly if the vase is composed of a good thermal conductor such as a metal. If the vase is composed of a poor thermal conductor such as glass, ceramic, or plastic, it is desirable to enhance the thermal conduction of heat from the water to the cold plate of device  1 . A typical configuration of a thermal conductor is shown in  FIG. 1 . The thermal conductor  15  can have a base disk which is positioned on the upper surface of the cold plate and can include an elongated portion which is configured to extend from near the surface of the water, upper horizontal line therein, in the vase  10  to the base disk portion of the thermal conductor  15  which is positioned on top of the cold plate  8  and underneath the vase  10 . If the vase  10  is sitting on the base disk portion of the thermal conductor  15  that is, in turn, positioned on the cold plate  8 , the elongated portion of the thermal conductor  15  can extend through a hole in the bottom of the vase. The thermal conductor  15  can have a large enough diameter base disk, where it contacts the cold plate directly, to efficiently transfer heat from the water in the vase into the cold plate and vice versa. This embodiment is useful when the vase is made of a material that poorly conducts heat such as glass. 
     Alternatively, if desired, the device  1  can be placed in thermal contact with the upper section of the water in the vase. The advantage to this approach is that a thermal conductor may not be required extending through the center of the vase as the cold water produced by the device will cause convection directly. If the vase is built of a thermally conductive material such as metal the device can be brought into thermal contact virtually anywhere in or on the vase. 
     If the vase is composed of a transparent material such as glass or plastic it can generally be more aesthetically desirable to place the cold plate under the vase and use a thermal conductor  15  that extends up through the center of the vase to near the surface of the water to cause efficient transfer of heat from the water in the vase by conduction and convection, cooling or heating the water from the inside out, minimizing thermal load. 
     In addition, it can be desirable to use a vase composed of a poor thermal conductor, such as glass, ceramic, or plastic to minimize the heat gain from the ambient air. If the surface of the vase is closer to the ambient temperature due to the poor thermal conductivity of the walls of the vase, less heat will flow into the water putting less burden on the cooling device allowing the device to be smaller, consume less energy, and will cause less condensation on the exterior of the vase. In this case the thermal conductor is required if the cooling device is located underneath the vase. If the thermal contact is made by placing the cooling device at, in, or near the top surface of the water in the vase an additional thermal conductor may not be required. 
     As an alternative, the water in the vase can be circulated out of the vase by tubes through the cold plate attached to the thermoelectric device or other heat/cool device and back to the vase. This is generally less desirable aesthetically and functionally, but can be desirable for use in larger vases as the larger apparatus required can be remotely located out of sight. It also can facilitate larger cooling devices such as conventional gas compression or absorption cooling devices. 
     As another alternative, the cold plate can be liquid cooled or heated and the heat transferred to or from the cold plate by circulating the liquid to a remote heat exchanger or cooling device. 
     The temperature controlling system  100 ,  FIGS. 1 and 2 , is provided for plants such as cut flowers that cools and/or heats water in at least one container such as a vase. 
       FIG. 3A  illustrates one embodiment of the present invention. A temperature controlling system  100  includes at least one thermoelectric module  102  therein. The thermoelectric module  102  may be replaced by any device that can remove heat from a surface such as cooling coils. In order to remove the heat, at least one heat sink  104  or heat exchanger may be used. In order to provide a more efficient heat transfer between the vase  1  and the module  102 , a cold plate  106  is placed there between. A temperature sensor  108  on or near the cold plate  106  may also be employed to monitor the temperature of the vase  1  by the micro-controller  110 . If the temperature of the vase  1  falls below a given value, the current can be reversed in the thermoelectric device  102  by the micro-controller  110  to heat the water in the vase  1 . The temperature controlling system  100  also may include a thermal conductor  15  to facilitate transfer of heat from/to the water in the container and to minimize a temperature differential in the water in the vase. The temperature controlling system  100  is controlled by a micro-controller  110  having one or more micro-processors therein being of conventional design and programmed to operate the system  100 . A touch switch  112  may be used to turn the system on. The temperature controlling system  100  may include current and voltage sensing devices  114  to measure the temperature of the module and relating this to the ambient temperature and the temperature of the water. Further one or more LEDs in the light indicator  116  can be used to indicate the operating condition of the system. To remove heat from the thermoelectric module  102 , at least one fan  118  cools the heat sink  104  and increases air flow in and around the system,  100 . The fan speed is also monitored and adjusted by the micro-controller  110 . If needed one insulating layer  16 ,  FIG. 2 , may be used inside the vase at the bottom to prevent excessive cooling and inadvertent freezing of the ends of the flower stems where they rest at the bottom of said vase. Clearly a plastic spacer can be used to prevent over cooling of the stem ends. Many sensors may be employed in the system  100  such as at least one humidity, moisture, or dew point sensor to detect the conditions when water may condense on the device and/or the container; at least one photosensor to detect ambient light levels; at least one illumination device to provide lighting to the flowers in the vase for photosynthesis, bio-regulation, and aesthetic purposes that can be scheduled and controlled by the micro-controller/processor; and at least one water level sensor to detect the need to add water to the vase and to further communicate this information. The water level sensor or device may be a thermochromic dye, ink, strip, film, or other temperature indicator that can be applied or attached on or in the vase as the water is colder or warmer where the water contacts the surrounding material such as the surface of the vase. 
     The temperature controlling system  100  may also include at least one communication port, power line carrier such as HomePlug, WIFI connection to the Internet, RF link such as Bluetooth, or light communication such as an IR port so as to be able to communicate with the temperature controlling system. 
     The temperature controlling system  100  may also include with the micro-controller  110  at least one real time clock for controlling the time of day and calendar operation of the device with the micro-controller. Also included in another embodiment would be at least one auxiliary output control such as a relay to control other devices such as a water dispensing system, additional lighting, ventilation, and the like. Also included in system  100  may be at least one speaker or sound producing device to alert a user to the condition of the system and/or the container, such as a low water condition or temperature out of intended range. 
     Another feature of the present invention is an odor enhancing or freshening device/means  120 ,  FIG. 3A , in the form of a card, strip, or other form that is inserted into or adjacent to the air flow through or from the heat sink or other heat exchanger. Many hybrid roses and other flora have lost their natural aroma due to selective breeding; by enhancing the aroma of the flora, the user can enjoy a more complete aesthetic experience. 
       FIG. 4  illustrates a possible flow diagram for a microprocessor used in a microcontroller of the present invention. The system  100  is started  400  by a switch. Upon turn on, the microprocessor will request user inputs  404  as applicable data is read  402 . These user inputs  404  may not be requested if the user has already input them from a prior turn on. The user inputs would include such items as date, time, flora, operating times, etc. Next, the system  100  would read applicable variables  406  through sensors, etc., such as present ambient temperature, light, water temperature, etc. After reading the data and variable, the system  100  would operate the system  100  and adjust various indicators  414  such as operating condition. If the conditions are not within specification, the microprocessor would output alarms  410 , visibly, by sounds, verbally, or otherwise. The system  100  would be terminated or end  412  operations if by user inputs or out of limit conditions. 
       FIG. 3B  illustrates a generic temperature controlling system  200  that includes a cooling/heating device  202 . The device  202  may employ a water circulator  204  with a heat exchanger therein. Water is circulated through lines  206  into a heat exchanger  208  located inside the vase or outside of a container  210  such as in the base. The circulating water is separate for the water in the container  210 . As noted above, appropriate controls, sensors, power, etc., would operate the cooling/heating device  202 . In the preferred embodiment above, no water circulation is required since heating/cooling of the water is accomplished by means of the thermoelectric module, the cold plate, and the vase walls, and if there is not sufficient heat conduction, a temperature conductor may be added to the vase as noted above depending on the material of the vase walls. 
     Since many modifications, variations, and changes in detail can be made to the described embodiments of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents.