Abstract:
A system and method to deice or remove snow or ice accumulated on a surface comprises a weather sensor, control means, a compressor containing a deicing agent, a heater to heat the agent, a second deicing agent stored in a second storage tank in communication with the compressor, and a means for distributing the deicing agents through one or more zones, each zone including a sprinkler head and piping. When air temperature is below freezing and humidity exceeds 99%, the control means causes a deicing agent to be heated, and the heated agent distributed through a zone. The second agent is distributed through the zone, then a pressurized gas purges the zone of residual agents. This is repeated for each zone; after a specified time, air temperature and humidity are determined, and the cycle is repeated if needed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/659,563, filed 9 Mar. 2005, the contents of which are incorporated by reference herein in their entirety. 
     
    
     FIELD OF THE INVENTION  
       [0002]     Embodiments of this invention include a system for deicing of driveways, walkways, sidewalks and like surfaces that surround a residence or business. In particular, an embodiment of this invention includes a storage tank for holding a deicing solution, one or more sprinkler heads positioned proximate a surface to be deiced, a control unit, a weather station or sensor, and a compressor and source of compressed gas, connected by the appropriate plumbing and electrical connections, such that at specific weather conditions, a deicing solution can be dispensed, and the plumbing then purged of residual deicing solution, leaving the system ready for reuse without the sprinkler heads becoming frozen shut.  
       BACKGROUND OF THE INVENTION  
       [0003]     During winter months in parts of the northern hemisphere, many people can be found outside their home or apartment, laboriously wielding a snow shovel to remove snow from their driveways and walkways. Sometimes the local government sends a truck to plow the streets and/or deposit a melting agent, such as salt, on snow-covered and/or icy areas, but this does not solve the individual&#39;s problem of getting from their home to the plowed streets. The task of removing accumulated snow from driveways, walkways, and sidewalks is often accomplished by the individual performing hard, manual labor, using a snow shovel to scoop up, lift, and heave the snow to the sides. In addition to shoveling snow, operators of businesses face the added task of shoveling snow or depositing salt, sand or other traction promoting materials on sidewalks and walkways adjacent to their businesses to provide traction for employees, pedestrians and customers to safeguard against individuals slipping and possibly being injured. These types of shoveling tasks are physically demanding, so much so that people over the age of fifty are cautioned not to perform this laborious job as it can be dangerous, especially for those who are not physically fit. While some businesses and residences employ devices such as heating coils or place steam lines under their sidewalks, walkways and the like, to effect snow and ice removal, this approach is not commonly used. Thus, there is both a long-felt and unmet need for a device that can prevent snow and ice from accumulating on the pedestrian areas surrounding a structure, such as a residence, business, or the like.  
       BRIEF SUMMARY OF THE INVENTION  
       [0004]     An object of the present invention is to provide a deicing system which will be actuated automatically when the air temperature reaches a specified temperature and the air contains a specified moisture content.  
         [0005]     Another object of the present invention is to provide a deicing system in which the pipes and sprinkler heads through which the deicing solution is dispensed are purged of residual deicing solution between uses.  
         [0006]     Still another object of the present invention is to provide a deicing system which can be used as a stand-alone system, or which can be integrated into a lawn sprinkling system.  
         [0007]     Another object of the present invention is to provide a deicing system that is durable and can withstand repeated use in low temperature environments.  
         [0008]     An embodiment of the present invention is a system and method to deice or remove snow or ice accumulated on a surface comprises a weather sensor, control means, a compressor containing a deicing agent, a heater to heat the agent, a second deicing agent stored in a second storage tank in communication with the compressor, and a means for distributing the deicing agents through one or more zones, each zone including a sprinkler head and piping. When air temperature is below freezing and humidity exceeds 99%, the control means causes a deicing agent to be heated, and the heated agent distributed through a zone. The second agent is distributed through the zone, then a pressurized gas purges the zone of residual agents. This is repeated for each zone; after a specified time, air temperature and humidity are determined, and the cycle is repeated if needed.  
         [0009]     An exemplary embodiment of the present invention is a system to reduce snow or ice accumulation on a surface, the system comprising:  
         [0010]     a weather sensor, the weather sensor including a means for determining air temperature and a means for determining air moisture (humidity);  
         [0011]     a control means in communication with the weather sensor;  
         [0012]     an agent to reduce snow or ice accumulation on the surface, the agent having a freezing point and a boiling point;  
         [0013]     a compressor, the compressor including a supply tank for the agent, the supply tank further comprising a means for heating the agent to a temperature between the freezing point and the boiling point, the compressor being in communication with the control means;  
         [0014]     a means for distributing the agent, the means for distributing the agent being in communication with the compressor and the control means;  
         [0015]     a zone, the zone in communication with the means for distributing the agent, and wherein the zone comprises a sprinkler head in fluid communication with the means for distributing the agent; and  
         [0016]     a means for purging the distributed agent from the zone;  
         [0017]     wherein when the weather sensor determines that the air temperature is less than a specified temperature and the humidity is greater than 99%, the control means is actuated and communicates with the means for heating to heat the agent, wherein the heated agent is water; the heated water being distributed to the zone for a period of time specified by the control means, and the control means actuates the means for purging the agent, the agent being purged from the zone for a period of time specified by the control means.  
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0018]      FIG. 1  is an example illustrating, in an embodiment of the invention proximate to a residence, the deployment of sprinkler heads along the length of a driveway, walkways and a sidewalk, and representative surface coverage of the sprinkler heads.  
         [0019]      FIG. 2  is a schematic diagram illustrating the deicing system.  
         [0020]      FIG. 3  is a schematic diagram illustrating the controller unit.  
         [0021]      FIG. 4  is a flow chart of the system logic.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0022]     An embodiment of the present invention is shown  FIG. 1 . Deicing system  10  comprises a weather station (or sensor)  20 , a controller unit  40 , a compressor tank  60  which is in communication with a water supply  70  and an air supply  80 . The compressor tank  60  is in communication with one or more zones  90   a ,- 90   e , with each zone comprising one or more sprinkler heads  92 . The controller unit  40  is in electrical communication with the weather station  20 , the compressor tank  60 , and the actuators  88  which open the flow of air, deicing solution or water to the various zones  90   a - 90   e.    
         [0023]     The weather station (or sensor)  20  may generally be positioned in the outside environment, where air temperature and moisture content can be measured directly. However, depending upon the particular embodiment of weather station, the weather station  20  could be physically located inside a structure, providing the weather station  20  has probes that can be positioned outside to monitor the appropriate conditions, and transmit that data to weather station  20 . The transmission of the temperature and air moisture can be done using either wired or wireless communications means, known to those skilled in the art.  
         [0024]     Weather station  20  comprises a temperature probe or sensor  22  and a humidity/moisture sensor  24 . Weather station  20  may include other functions, such as devices to measure the barometric pressure, wind speed and direction, and the like, but these are accessory functions not necessary for operation of this embodiment of the present invention.  
         [0025]     The controller unit  40  is used to set the operating parameters of the deicing system  10 . Controller unit  40  can be positioned outside of the structure, or may be positioned inside the structure. When controller unit  40  is located in the outside environment, it would be enclosed in a weather-protective casing, which casing can be opened by the user for access to the controls. Controller unit  40  includes a display  42 , a deicing control  44  to adjust the amount of deicing solution to be dispensed, and one or more buttons  46 , or other equivalent means, for setting the parameters of the system. In the embodiment illustrated in  FIG. 1 , control  44  is shown having three settings, designated at “Light”, “Medium” and “High”. In this embodiment, these settings are used for adjusting the output of the system to different weather events, such as, for example only and not intended as any limitation, “Light” to indicate a light snow coating, of less than about 2 inches; “Medium” to indicate a proposed snow accumulation of between from about 2 inches to about 6 inches of snow, and “High” for either a proposed snow accumulation of greater than 6 inches, or for a forecasted icing event. By adjusting control  44 , the cycling of the water dispersal, deicer solution dispersal and the length of time of the off period can be varied. When the deicing system  10  is being installed, the water temperature needed for effective deicing will be calculated, and the system parameters set accordingly. Changes in the water temperature could be readjusted at a later date as the need arises. Buttons  46  can be buttons, switches, DIP switches, set screws, toggle switches, or other type of either electronic, electrical or electromechanical means for adjusting a control device.  
         [0026]     Included within the body of the controller unit  40  is a microprocessor  48 , a connection to a source  50  of electrical power, which could either be a battery or a connection to the building&#39;s power supply. An On-Off switch  98  is in communication with the source of electrical power, and with the microprocessor  48 . Reference numeral  52  refers to the input from the weather station  20 . The microprocessor  48  is in communication with the display  42 , deicing control  44 , buttons  46 , and with one or more memories  54  and  56 . The first memory  54  could be a read only memory, containing, for example only, factory-specified operating parameters and other defaults for the system, while the second memory  56  can be a random-access memory (“RAM”) to store user-specified commands. The microprocessor  48  is also in electrical communication with the outputs  58   a - 58   c , which transmit to the compressor control means  62 , heater  64 , and the distribution means  88 . Additional inputs and outputs could be built into the controller unit as needed. The inputs and outputs can be chosen form conventional means such as RS-232C, parallel, serial, small computer serial interface (“SCSI”), Universal Serial Bus (“USB”), IEEE 1394 (“Firewire”), phonoplugs, telephony, or other wired or wireless communications means now known or to be developed.  
         [0027]     The heater  64  is used for heating the water, and the actuator means  88  functions in dispensing either air, water, and/or deicing solution to each zone  90   a - 90   e , using the appropriate valves  94   a - 94   e , respectively. The deicing solution, while not being specifically heated by its own heater, will generally be heated because of its&#39; proximity to the heated water.  
         [0028]     The controller unit  40 , as well as the weather station  20 , the compressor tank  60  and distribution means  82 , can be fitted with a back-up battery for use in the event of a power failure. Such back-up batteries can be either conventional batteries such as alkaline or lithium batteries, rechargeable batteries such as nickel-cadmium, nickel-metal hydride or the like, or wet-cell storage batteries, as appropriate.  
         [0029]     The compressor tank  60  can be partitioned such that one portion serves as a water tank  66  and the other serves as a deicing solution storage tank  68 . An alternative embodiment can employ separate compressor tanks, one for water, one for the deicing solution, and, if necessary, another for compressed air, all in operative communication with the control unit and the actuators.  
         [0030]     The compressor tank  60  is electronically operated, but could be operated by another source of electricity, such as a battery, a generator; or by using gasoline, kerosene, diesel fuel or the like.  
         [0031]     The water supply  70  to the compressor tank is generally the same source of water used to supply the structure around which the deicing system  10  is dispersed. If the deicing system  10  is not being used near a structure, or an additional supply is needed for an embodiment positioned around a structure, the water supply  70  can originate from a well, municipal water source, storage tank, water tower, rainwater collection means, or other means of supplying water to the system. Water enters the compressor tank  60  by means of valve  72 , and exits the compressor tank through exit valve  74 . The deicing solution exits deicing solution tank  68  by through deicing exit valve  76 .  
         [0032]     The air supply  80  to the compressor tank is the air drawn in from the surrounding environment through a valve  82  on the compressor tank  60  and a second valve  84 . When activated, air exits the compressor tank  60  through air exit valve  86 . Alternatively, the air supply can be a separate source, such as an external compressed air tank or a pressure container, which is in communication with the compressor tank  60 .  
         [0033]     The deicing solution employed with the present invention is selected from those in current use today, or which may be developed in the future. Such deicing solutions can be chosen from a salt-water mixture, using salts such as rock salt, sodium chloride, potassium chloride, calcium chloride; compounds such as an aqueous solution of ethylene glycol, propylene glycol, alcohols. or mixtures thereof.  
         [0034]     One or more conduits, such as tubing or piping  120  connects the outlet of the actuator block  88  with the sprinkler heads  92 . The conduit can be selected from copper piping, cast iron piping, concrete piping, or plastic piping, such as polyvinyl chloride (“PVC”) piping, high density polyethylene (“HDPE”), low density polyethylene (“LDPE”) or other materials commonly employed by those skilled in the art, or to be developed in the future. In one embodiment, the piping  120  is buried underground; the type of piping chosen may also be dependent upon anticipated environmental conditions and local building codes. Conventional items, such as plumbing fittings, elbows, tees, and other connectors, and the structure of the sprinkler heads, are not shown in the drawings for purposes of clarity.  
         [0035]      FIG. 2  illustrates one example of deicing system  10  deployed around a residence  100 . The residence includes an attached garage  102 , a driveway  104 , walkways  106 ,  108  and a sidewalk  110 . For purposes of example only, the remainder of the property is covered with grass  112 . A plurality of sprinkler heads  92  are dispersed along the length of the driveway, walkways and the sidewalk, and in this example, the system is divided into four zones, zone  90   a  for the driveway  104 , zone  90   b  for walkway  106 , zone  90   c  for walkway  108  and zone  90   d  for sidewalk  110 .  
         [0036]     The sprinkler heads  92  are aimed at the driveway  104 , walkways  106 ,  108  and sidewalk  110  rather than aimed at the grass  112 . The sprinkler heads  92  are connected by conduits  120 . The weather station  20 , controller unit  40 , and compressor tank  60  are not shown in this figure, but can be positioned either inside or outside the residence or garage, as determined by the user. The deicing solution is dispensed by the sprinkler heads onto the areas of coverage (sidewalks, driveways, walkways) and would prevent snow and ice from building up in areas that are covered by the sprinklers.  
         [0037]     As used within the context of the present specification, the terms driveway, walkway and sidewalk are meant to include the general terminology used to describe such surfaces, and is also intended to include surfaces that may be either paved; unpaved; covered with dirt, rock, gravel or the like; made of concrete; stones such as paving stones, flagstone and the like; brick; various types of block; wood; composite lumber and/or wood-like materials; or paved with asphalt or the like, or concrete, or mixtures thereof as used for driveway, highway or road paving.  
         [0038]     Also, the term “ice”, as used herein, is intended to cover frozen precipitation, such as freezing rain, molten snow which has frozen, ice in its conventional meaning, sleet and hail. The term “snow” as used herein is also intended to include snow in its conventional meaning, and sleet, because sleet may freeze and turn to ice, yet accumulate to depths comparable to snow accumulations, depending upon the weather conditions.  
         [0039]     The operation of the deicing system  10  is shown in  FIG. 3 . At  100 , the controller determines whether the outside temperature is below 32° F. (0° C.) and whether the air moisture content exceeds 99%. If the answer to both is Yes, at  200  the controller turns the water heater  64  and compressor  60  on. At  400   a , the water is heated to a temperature that is above the freezing point but below the boiling point of the water. Thus, the water is heated to a temperature that ranges from about 33 degrees F. (0.6 degrees C.) to about 210 degrees F. (99.9 degrees C.); the water is heated to a temperature that preferably ranges from about 35 degrees F. (1.7 degrees C.) to about 150 degrees F. (65.6 degrees C.), more preferably ranges from about 40 degrees F (4.4 degrees C.) to about 100 degrees F. (37.8 degrees C.), and most preferably ranges from about 45 degrees F. (7.2 degrees C.) to about 60 degrees F. (15.6 degrees C.). In another embodiment, the water is heated to a temperature ranging from about 45° F. (7.2 degrees C.) to about 50° F. (10 degrees C.). The specific temperature range for the heated water is affected by the outside air temperature, and the distance that the water in the various zones has to travel from the location of the water tank to the sprinkler head. Thus, while a temperature range of between 45 degrees F. (7.2 degrees C.) to about 50 degrees F. (10 degrees C.) is specified herein for one embodiment, this range may actually be wider because of environmental conditions. At  400   b  the tank is pressurized to a pressure that is sufficient to distribute the solutions across the site for the desired time. The pressure can be affected by factors such as the type and diameter of the conduits, the number of sprinkler heads in a zone, and the size of the various zones. Generally, the pressure will range from about 50 psi (384.7 kPa) to about 200 psi (1379 kPa). In one embodiment, the pressure can range from about 100 psi (689.5 kPa) to about 130 psi (896.3 kPa), with a pressure of 120 psi (827.4 kPa) being effective.  
         [0040]     At  500   a , the controller selects which zone will be deiced, based on how the controller  40  was programmed, and at  500   b  the controller opens the outlet valve to the selected zone. At  600 , the selected hot water valve is opened for period of time. The time period which the hot water valve is opened is specified by the user. After the specified time period has elapsed, at  700   a  the controller then closes water valve; and then ( 700   b ) the controller opens deicing solution valve for a specified amount of time. Once the specified deicing period has elapsed, at  800   a  the controller closes deicing solution valve, and at  800   b  the controller then opens air valve such that ( 800   c ) the piping to that zone is purged of residual liquid; and then, at  800   d , the tank is depressurized. In the interim ( 900 ) the controller turns on the valve from the water supply and refills, or “tops off” the water tank. At step  1000 , the next zone to be treated is selected by the controller, and at  1100 , steps  600 - 1100  are repeated until all the zones in the system have been cycled. Once all of the zones have been treated, at  1200  the system waits for a specified time period, determined either by the user, by the system&#39;s defaults, or other parameters programmed into the controller, such that at  1300 , the system will reanalyze the weather conditions and proceed to step  100 , repeating the process as needed, and thereby prevent snow and ice buildup along the treated surfaces, and/or facilitate the removal of accumulated snow and ice.  
         [0041]     It is anticipated that embodiments of the present invention can be installed using equipment similar to that used for installation of automatic lawn sprinkler systems. An existing sprinkler system could be upgraded to a deicing system by addition of elements of the present invention, such as, but not limited to, the compressor tank  60 , the controller unit  40  and the weather station  20 , either alone or in combination, using fittings compatible with the underground piping and sprinkler heads already in place. A changeover from an automatic sprinkling system to a deicing system would require changing the direction of the sprinkler heads, and this could be performed by either the user or a service technician.  
         [0042]     Although this invention has been described as being applicable to use around either residential or commercial structures or properties, components of the system could be scaled up or down in size such that alternative embodiments could be used upon a variety of other surfaces which often require deicing. Examples of other commercial areas in which this system could be deployed include loading docks, parking lots, railroad tracks, stairs, steps, ramps, decks, security barriers, fire escapes and roofs. An embodiment of this invention could be installed on a railroad car, and used to deice a length of railroad track. Such use on a railroad may be of particular importance in regions where the railroad tracks go through mountainous areas that are often subject to closing because of snow and ice accumulation on the tracks. Embodiments of this system could also be used in the aviation industry, on areas such as tarmacs, taxiways, runways, landing strips, helipads, and smaller embodiments mounted on aircraft for deicing of aircraft surfaces such as aircraft engines, aircraft wings, aircraft tails, helicopters, and helicopter rotors.  
         [0043]     Therefore, although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made only by way of illustration, and that numerous changes in the details of construction and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.