Abstract:
A windshield wiper solution dispenser located at vehicle servicing stations or fuel stations. The stations are usually located in geographic regions which are exposed to long periods of freezing temperatures. The solution dispenser is configured to maintain the solution within the dispenser in a liquid state during outside freezing temperatures. The dispenser has an interior region which contains the solution and also has a heater to keep the solution in a liquid state. A plurality of monitors or sensors are provided as well as temperature controlling mechanisms. In one embodiment the heater has a programmable logic device or controller to monitor the interior temperature and exterior temperatures as well as the solution liquid level and adjust the heater and the amount of solution contained in the dispenser as needed. The heater can be a coiled electrical resistance heater, an electrical liner heater, or a plurality of thermoelectric units which can be placed around the outside of the dispenser. The solution can be circulated through a gas heating source, as well as other environmentally friendly heating system such as solar powered panels and the like.

Description:
RELATED APPLICATIONS  
       [0001]     This application claims priority benefit of U.S. Ser. No. 60/638,245, filed Dec. 21, 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     a) Field of the Invention  
         [0003]     The current embodiment relates generally to the standard windshield wiper dispensing containers found in many gas stations and service stations. More particularly, the current embodiment deals with windshield wiper dispensing units found in cold climates which have environment temperatures dropping below the freezing level and thus freezing the fluid within the standard windshield wiper dispensing unit. This concept relates directly to preventing the fluid contained within the windshield wiper dispensing unit from freezing during the cold winter months.  
         [0004]     b) Background Art  
         [0005]     The various prior art references discussed below fall into three general categories. One category is embodiments that show methods of automatically refilling windshield washer fluid at a service station. A second type of disclosure is a water heater that is submersible. The third type of disclosure is generally relating to windshield wiper fluid for the vehicle itself and replenishing the windshield wiper fluid. These various prior art references are discussed in detail below.  
         [0006]     U.S. Pat. No. 6,585,011 (Willeke, Jr. et al.) shows a system for supplying windshield washer fluid to squeegee buckets at a service station. A fluid quantity sensor  214  is schematically shown in  FIG. 2  that indicates whether the window washing fluid is low. As shown in  FIGS. 4   a - 4   c , there is a non-electrical system for maintaining fluid in the bucket  430 . When the fluid level is sufficiently high, the spring  412  relaxes to a certain degree so the valve  420  shuts off the insertion of fluid into the open chamber region of the bucket  430 . The other very schematic embodiments show other means for refilling the bucket with windshield washer fluid. For example, as shown in  FIGS. 6   a - 6   c , the system  480  has a switch where the low contact  492  engages the contact arm  488  when the fluid level is low. The contact arm  488  engages the high point  494  when the weight of the bucket  430  extends the opposite end of the contact arm  488  downwardly and the fluid dispersion through the squeegee bucket fluid tube  454  ceases.  FIGS. 8-9  show a schematic perspective view of the apparatus in an operating environment.  FIG. 10  shows a hose  508  and a nozzle  510  adapted to fill windshield wiper fluid of a vehicle.  
         [0007]     U.S. Pat. No. 6,484,907 (Evans) shows a portable fluid dispensing apparatus that generally comprises a fluid container  20  (see  FIG. 2 ), an air compressor  40  (see  FIG. 3 ), and a dispenser gun  80  (see  FIG. 5 ). Apparently, when the dispenser gun is activated the pressure within the container is decreased. The decrease in pressure is detected by a pressure switch which then activates the air compressor. The air compressor is in communication with the inner sealed region of the container  20  and maintains a sufficiently high pressure therein to continue dispensing fluid.  
         [0008]     U.S. Pat. No. 6,283,656 (Jiang) shows a handheld deicer that has a sprayer which ejects antifreeze liquid onto the windshield of a car. A brush, scraper, sponge or squeegee are interchangeably mounted onto the nozzle region (see  FIG. 11 ). In one form, a heater is placed in the nozzle where an electrical current is adapted to heat the nozzle region.  FIG. 9  shows an embodiment with two compartments for chemical heating. When the two liquids  44  and  46  meet in the passageway of the nozzle  52  and mix before injecting up the opening  56 , a chemical reaction between the two chemicals is exothermic whereby creating heat.  
         [0009]     U.S. Pat. No. 5,257,423 (Cobsen et al.) shows a service island wash station enclosure adapted to be located in a service island at a gas station (see  FIG. 1 ). A central wash station is employed so the patron can presumably just fill their car with gasoline and then wash their hands. The disclosure discusses hot air hair dryers, warm water dispensers and the like.  
         [0010]     U.S. Pat. No. 4,759,470 (Jacobs) shows an automobile windshield washing unit where as shown in  FIG. 2 , the unit is cross-sectionally shown where the upper portion is substantially symmetric to lower portion about a middle horizontal plane. As shown in  FIG. 1 , the upper portion of the unit  10  is adapted to dispense towels and the lower portion houses the lower bin which in turn holds the washing solvent and the squeegee  38 .  
         [0011]     U.S. Pat. No. 4,480,173 (Butterfield) discloses a water heater that is adapted to heat water to various temperatures. The water heater in general includes a water level indicator, temperature sensor and other various components. The sole figure in the application schematically shows a water heater arrangement.  
         [0012]     U.S. Pat. No. 4,143,792 (Rex) discloses a windshield washing apparatus having two bins as shown in  FIG. 1 . A paper towel distributing apparatus  18  is shown in the upper portion. As recited in column  2 , line  43  either of the multipurpose bins  20  and  22  can be used as a receptacle for spent paper towels.  
         [0013]     U.S. Pat. No. 4,068,116 (McKinstry) shows and immersible water heater that is adapted to be used with animal watering buckets. The heater has a heating element and a temperature-sensing member that cooperates with a thermostat.  FIG. 1  shows the apparatus in use in an operating environment.  
         [0014]     U.S. Pat. No. 4,000,835 (Bassett et al.) discloses a windshield washer service apparatus. As shown in  FIG. 1 , the automobile&#39;s reservoir  70  is shown where the hose  66  is in communication with the cabinet  20  and is dispensing windshield wiper fluid therefrom.  
         [0015]     U.S. Pat. No. 3,594,849 (Coshow) discloses an apparatus for cleaning a surface such as a windshield. As shown in  FIG. 4 , the cleaning head means  4  is being applied to the windshield  70 . The disclosure is directed towards a cleaning apparatus that employs a suction section that is adapted to remove debris from the surface to be cleaned.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  shows an elevational view of a typical service station;  
         [0017]      FIG. 2  shows a perspective view of a windshield wiper solution dispenser unit;  
         [0018]      FIG. 3  shows a cross-sectional view of a windshield wiper solution dispenser unit;  
         [0019]      FIG. 4  shows an alternative cross-sectional view of the windshield wiper solution dispenser unit;  
         [0020]      FIG. 5  shows an alternative cross-sectional view of the windshield wiper solution dispenser unit;  
         [0021]      FIG. 6  shows a perspective view of a windshield wiper solution dispenser unit with temperature and solution controller;  
         [0022]      FIG. 6A  shows a perspective view of a seal plate;  
         [0023]      FIG. 7  shows a perspective view of the programmable logic controller mounted on the service station column;  
         [0024]      FIG. 8A  shows a perspective view of the Peltier thermal electric unit;  
         [0025]      FIG. 8B  the shows a perspective view of the heating coil unit;  
         [0026]      FIG. 9  shows a control diagram of the digital hardware;  
         [0027]      FIG. 10  shows a process diagram for setting the containing region temperature;  
         [0028]      FIG. 11  shows a process diagram for the temperature adjustment control logic;  
         [0029]      FIG. 12  shows a process diagram for the water level adjustment control logic.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]     The environment within which the present embodiment operates will be provided first, followed by the present embodiment itself. After discussion of the elements of the present embodiment, discussion of the operation of the present embodiment will be provided.  
         [0031]     The present embodiment generally relates to windshield wiper dispensers which hold wiper solution and squeegees and are commonly found at gas stations and/or convenience stores. Generally, these windshield wiper dispenser containers are positioned outside next to the gas pumps themselves, and have both a washer-solution-containing section and a paper towel wiping section. These windshield wiper containers are generally exposed to the elements on a 24-hour basis. Consequently, during extremely low temperatures, the solution contained within the windshield wiper solution container can freeze with or without the squeegee held within the solution, thus making the windshield wiper dispenser container inoperable until the outside temperature rises above the freezing level. After the outside ambient temperature is raised above freezing, the solution still has to thaw out, which takes time based on the warmth of the ambient air temperature outside of the container.  
         [0032]     There will now be a general discussion of the present concept as used in the gas station and service station  10  environment. This will be followed by a more detailed discussion of the particular control elements of the concept as they apply within the environment.  
         [0033]     Referring now to  FIG. 1 , in general the concept of a windshield wiper solution dispenser is used in gas stations and service stations  10 . In climates where temperatures fall below freezing, the windshield wiper solution dispenser  20  will generally have the wiper solution frozen due to exposure to the outside elements. Ready access during the winter months of a nonfrozen wiper solution held within a windshield wiper solution dispenser  20  is beneficial to and consistent with the idea of convenience and service at the gas station  10 . Still referring to  FIG. 1 , the general operation and use of the windshield wiper solution dispenser  20  includes the windshield wiper solution dispenser positioned on the column  14  of the gas or service station  10 .  
         [0034]     Alternatively, the windshield wiper solution dispenser  20  can be incorporated within an ashtray/garbage can ground unit which has the ashtray on the top portion of the island or trash can, the interior volume of the island holds the trash can, and the windshield wiper dispenser is positioned along with the towel dispenser on the outside face or within an interior volume portion of the trash can island.  
         [0035]     Generally, the dispenser  20  is located within the pump station island  16  and is either located on the trash cans or next to the gas station pumps. The user can pull the squeegee  22  out of the dispenser  20 , and using the liquid solution contained within the squeegee  22 , clean the windshield  18  of the automobile. Of course, if the solution within the dispenser  20  is frozen, the squeegee  22  may be fixed in the solution itself, and thus frozen in a single block within the windshield wiper solution dispenser  20 . As a practical matter, extracting the squeegee during temperatures below freezing for the remainder of the cold season may require the gas station attendant to disassemble the dispenser  20  and place it in a warm environment such as the inside of the gas station  10 , or utilize some heating elements to heat the solution and extract the squeegee.  
         [0036]     Thus, having the ability to utilize the squeegee  22  with the solution  21  in its liquid form during outside freezing temperatures, as seen in  FIG. 2 , will be beneficial to the convenience and use of the service station  10 .  
         [0037]     To provide this heating of the windshield wiper dispenser solution  21 , a system to regulate the water temperature within the solution dispenser  20  is provided. Referring to  FIG. 2 , a typical solution dispenser  20  is constructed out of a polyvinyl chloride frame material or some sort of aluminum sheeting material with an interior frame.  
         [0038]     While the following description of the solution dispenser  20  is provided for a unit which is mountable on a gas station stanchion or column of the overhanging parapet roof-protecting structure, other differently configured solution dispensers being designed for inclusion in previously mentioned island trash cans or other movable semi permanent components of the service station island are readily conceived.  
         [0039]     Generally, the top portion of the dispenser  20  has a paper towel dispenser section  24 , with the bottom portion of the dispenser unit  20  having a solution containing section  26 . Contained within the solution containing section  26  is the wiper solution  21  as well as the squeegee or wiping mechanism  22 . In the present configuration, the dispenser unit  20  has a dispenser front wall  32 , paper dispenser sidewalls  30 , a paper dispenser top wall  36 , and a back wall  28 . Similarly, the solution dispenser or containing section  26  has an angled front wall  42 , as well as parallel solution container sidewalls  40 , a solution container top wall  38 , and a back wall  37 . The solution container section  26  has an inner chamber which is defined by the aforementioned walls, and access to the inner chamber is through the top portion of the solution container top wall  38 . Access is achieved through the top wall squeegee port  46 , which is an opening within the solution container top wall  38 .  
         [0040]     In the current embodiment, a heating element  48  is provided at the bottom portion of the solution containing section  26  and is connected to a temperature control system which will be discussed below.  
         [0041]     Various heating elements can be utilized; two are detailed in particular below. Of the heating elements possible to be used to maintain the liquid phase of the solution, a heating coil element which utilizes an electrical resistance path can be used, also a Peltier thermoelectric unit type system. Furthermore, a heating element which utilizes say for example a natural gas, propane, or other external fuel heating source (such as solar powered panels and the like) may be provided to heat the solution within the dispenser, or heat solution which can be circulated in and out of the interior of the dispenser. Likewise, a heating element liner similar in operation to electric blankets could be utilized to line the interior or exterior walls of the dispenser to maintain a liquid phase of the solution.  
         [0042]     Still referring to  FIG. 2 , because it is common in the polar regions and colder regions of North and South America to expect the solution within the dispensers to be frozen during the water months, some form of indication to the customers at the service stations that the solution is available for use is needed to be provided on say for example the outside of the dispenser. Therefore, a heated solution indication light  400  is provided on the paper dispenser portion of the solution dispenser. The controller  100  will monitor the level of the solution within the container as well as the temperature of the solution and indicate the proper information on the display board or indication light  400 . For example, having an on signal  402  and an off signal  404  would enable customers to recognize that the solution contained within the windshield wiper dispenser is available for usage. Ways of keeping the solution heated will now be discussed in further detail.  
         [0043]     As previously mentioned and referring to  FIG. 3 , different means of distributing the heat from the heating element  48  to keep the wiper solution  21  in its liquid state can be utilized. In the current embodiment, shown in  FIG. 3 , includes an inner solution containing wall  52  which holds the wiper solution  21 . Separating the inner containing wall surface  52  from the outer containing wall surface  54  is an insulating airspace  50 . Within this insulating airspace  50  is positioned the heating element  48 . Referring briefly to  FIG. 8B , the heating element  48  in the current embodiment as shown is provided with heating coils  49  which are connected to a watertight seal  47 , and receive power from a 120-volt power supply routed through a solid-state relay  130 . Control of the solid-state relay  130  is provided by a programmable logic controller  100  which will be discussed below.  
         [0044]     Referring back to  FIG. 3 , the heating element  48 , as shown in the current embodiment with resistance heating coils, is configured to be replaceable if and when maintenance requires that the heating coils be replaced. Thus, the heating element  48  can be removed laterally from the base of the solution containing section  26  by unscrewing the attachment means and removing the heating element  48 .  
         [0045]     Still referring to  FIG. 3 , the heating element is turned on and the heat is radiated into the insulating space  50 , providing a relatively uniform temperature differential between the outside environment and the interior chamber of the solution containing section  26 . The insulating airspace  50  can include not only the entire interior chamber of the solution containing section  26 , but can be positioned at the bottom portion of the solution containing section  26 , effectively creating a solid dividing wall or membrane  54  between the solution containing section  26  and the insulating airspace  50 .  
         [0046]     The solid dividing wall or membrane  54  can be constructed of a heat-conducting material such as an alloy or a polyvinyl type of plastic. Fins extending from the top face of the solid dividing wall  54  up into the interior section of the solution containing section  26  can also be provided to transmit heat.  
         [0047]     Alternatively, referring to  FIG. 4 , a direct heat transfer from the heating element to the solution  21  can be provided. In this configuration, the divider is a porous divider or porous membrane  60  which enables the solution  21  to flow from the solution containing section top portion  61  into the solution containing section bottom portion  63 . Convection currents within the solution  21  will naturally occur through the use of the heating element  48  as the heated solution  21  rises and the cold solution falls within the solution dispensing containing section  26 , thus mixing the solution.  
         [0048]     The porous divider  60 , in one form, can have a plurality of holes  65  through which the solution  21  can flow. The porous divider  60  is substantially rigid enough to provide for support of the squeegee  22  as it rests within the interior chamber of the solution containing section  26 .  
         [0049]     In an alternative embodiment, and referring to  FIG. 5 , in lieu of utilizing heating coils  49 , the heating element  48  could conceivably use one or more Peltier thermal electric units. These thermal electric units  48  can be distributed along the inner containing wall surface  52  within the insulating airspace  50 , or conceivably positioned on the bottom of the solution containing section  26  at the bottom wall  44 . Referring briefly to  FIG. 8A , the Peltier thermal electric heating element  48  may require a larger voltage power source than what the digital logic controller device  100  utilizes.  
         [0050]     Consequently, a switching element such as a solid-state relay  130  is provided having a power source which provides at least 120 volts of power to the heating element  48 . The Peltier thermal electric unit  48  has a plurality of cooling fins  132  which, in one embodiment, could extend up into the inner chamber region of the solution containing section  26 . Thus heat from the thermal electric unit  48  would be disbursed into the solution  21 . It is well known as a method within the art to use Peltier-type thermal electric coolers and heaters to provide temperature control to conditioned air spaces. In operation, a voltage applied to the free ends of two dissimilar conducting materials creates a temperature difference between the conducting materials.  
         [0051]     Thus, there is a cool side and a hot side of the solid-state media. A typical thermal electric cooler or heater will consist of an array of positive and negative type elements that act as two dissimilar conductors. The array of elements is soldered between two ceramic plates or other heat gain and loss materials, and positioned electrically in series and thermally in parallel.  
         [0052]     As the DC current passes through one or more pairs of the elements from negative to positive, there is a decrease in temperature at the cold side junction resulting in absorption of heat from the environment. Further, heat is carried through the elements and released on the opposite hot side junction as the electrons from the current move from a high to low energy state. Thus, the heat gain and release capacity is proportional to the current and the number of conducting elements.  
         [0053]     Therefore, to produce the required heat generation, a reasonable amount of voltage  122  needs to be provided from the solid-state relay  130  and conducted through the current leads  136  and transferred between the conducting materials  134  to produce the desired heating effect.  
         [0054]     Referring back to  FIG. 5 , the Peltier thermal electric unit  48  can be positioned as required along the outside face of the inner dispensing wall  52 , thus providing a relatively uniform dispersion of thermal heat gain into the inner containing region of the solution containing section  26 .  
         [0055]     In addition to heating of the windshield wiper solution  21 , monitoring and filling of the wiper solution  21  level within the solution containing section  26  can also be provided.  
         [0056]     Referring to  FIG. 6 , a solution feed conduit is connected to the bottom portion of the solution containing section  26  to provide additional recharging of the windshield wiper solution  21  into the containing section. To monitor and control the solution level, additional control is provided within the programmable logic controller  100  along with a solution pump  82 , and the solution tank  84 . The controller operates a solution valve  86  and also provides a low level indication light  85  if the solution containing section  26  needs to be recharged manually.  
         [0057]     In one configuration, the monitoring of the windshield wiper solution  21  within the containing section  26  is performed at the seal plate  70  as seen in both  FIGS. 6 and 6 A. The seal plate  70  is in one embodiment constructed of a hard polyvinyl chloride or plastic material having attachment means such as screw holes that will attach to the outer surface of the solution containing section  26 . To provide a watertight seal, a sealing gasket  78  can be included on the back or rear surface  74  of the seal plate  70 .  
         [0058]     The solution feed conduit  80  is directed through the seal plate  70  and provides the required influx of new windshield wiper solution  21  into the containing section  26 . Also mounted to the rear surface  74  of the seal plate  70  are water level sensors  73  and interior temperature sensors  71 , as well as an outside or exterior temperature sensor  75 . Optionally connected to the seal plate  70  is the removable heating element  48 . In the current configuration, the heating element  48  is shown as the heating coil as previously discussed.  
         [0059]     Referring to  FIG. 7 , an exterior view of the control system is shown with the controller  100  attached to the outside face of the gas station or service station column  14 . To keep the controller  100  operational, a power line  114  is provided. Additionally, the exterior configuration of the controller  100  includes a controller cover  112 , a plurality of LED display lights  106 , an on-off heating control unit  108 , and an on-off solution pump control unit  110 .  
         [0060]     The controller cover  112  is attached via a plurality of hinges along the vertical edge of the controller case. To enter in the required temperature limits for the solution  21 , a digital keypad  14  is provided. Power is also connected to the solid state relay  130  as well as to the heating element  48 . Electrical connections are provided to the solution level gauge  120 , the inside temperature sensor  118 , and the outside temperature sensor  116 .  
         [0061]     Control of the temperature in one form can be provided by a programmable logic controller as seen in  FIG. 9 . This programmable logic controller  100  is required to take analog signals and convert them into digital signals, and then after performing the required control logic based on the various exterior signals, provide analog signals to the various analog control devices for operation of the machinery.  
         [0062]     Thus, the control hardware as previously mentioned is comprised of the exterior temperature sensor  116 , the interior temperature sensor  118 , and the water level sensor  120 . A plurality of amplifiers  154  are provided to filter the exterior analog signals to the required amplitude level for the analog-to-digital converters  152 . The analog-to-digital converters then provide the digital signal to the programmable logic control processor  160 .  
         [0063]     The digital and software logic is performed within the programmable logic controller  100 , and control signals are digitally sent to the analog controllers. The digital-to-analog converters  156  provide conversion from the digital signal to analog signal and then a plurality of amplifiers increase the amplitude of the analog signal to the required amplitude for controlling the solid state relay  130  as well as the pump valve control solid state relay  131 . To operate the programmable logic controller  100 , a power source  114  is provided with at least between 5 and 12 volts of power. Additionally, a 120-volt power source  122  is provided for the heating element solid state relay  130  as well as the valve control solid-state relay  131 .  
         [0064]     Still referring to  FIG. 9 , the user interface controls of the programmable logic controller  100  include a digital keypad  104 , the heat control  108 , and the water flow control  110 . The user has the option of, in this particular embodiment, setting the desired temperature differential between the interior solution-containing section  26  and the exterior temperature or outside temperature sensor  116 .  
         [0065]     This desired temperature setting is then stored in the memory chip  158  of the programmable logic device  100 .  
         [0066]     Still referring to  FIG. 9 , the user interface controls of the programmable logic controller  100  includes a digital keypad  104 , the heat control  108 , and the water flow control  110 . The user has the option of in this particular embodiment, setting the desired temperature differential between the interior solution containing section  26  and the exterior temperature or outside temperature sensor  116 .  
         [0067]     This desired temperature setting is then stored in the memory chip  158  of the programmable logic devices  100 .  
         [0068]     In operation, the programmable logic device  100  reads the desired temperature setting and displays the internal temperature as well as the external temperature and the setting on the LED displays  106 . The logic device then compares the internal temperature reading to the internal temperature setting, and sends the appropriate signal through the digital-to-analog converter  156  which then directs the electrical current flow on the thermal electric Peltier unit  48 .  
         [0069]     Referring now to  FIGS. 10 and 11 , a brief description of the data process flow will now be provided. The user will choose to power on at step  200  the programmable logic controller  100  and input the desired temperature setting at step  202 . The data is then stored in the programmable logic controller  100  at step  204  and the setting of the interior temperature range is complete.  
         [0070]     Once the desired internal temperature of the solution containing section  26  is stored, then the programmable logic controller  100  can perform the digital logic to determine whether or not to send a heating control signal to the heating element solid state relay  130  and thus power on the heating element  48 .  
         [0071]     This process is shown in  FIG. 11 . The process starts at step  210  and performs a while loop at step  212 , constantly polling the interior temperature at step  214 . Further, the programmable logic controller  100  also polls the temperature signals at step  216 ; thereafter, the digital logic performs a simple calculation to determine the absolute temperature differential between the interior and exterior of the solution containing region  26  at step  218 .  
         [0072]     Concurrently, the programmable logic controller  100  polls the recorded temperature setting at step  220 . Thereafter, the digital logic performs a decision block at step  222 , comparing the temperature set variable with the absolute temperature variable. If the temperature set is greater than the absolute temperature, the programmable logic controller  100  sends a digital signal to the heating element solid state relay  130  to turn the heating current on at step  224 . The while loop then continues at step  220 .  
         [0073]     If the temperature setting is not greater than but less than or equal to the absolute temperature at step decision block  222 , then the programmable logic controller  100  sends the digital signal to the heating element solid state relay  130  to turn off the electrical current to the heating element  48  at step  226 . The while loop is then continued at step  228  until the power to the programmable logic controller  100  is turned off.  
         [0074]     Similarly, the logic for operating the solution level control is as follows and is shown in  FIG. 12 . Starting at step  300 , a while loop is performed when the power at step  310  is on. The digital logic controller  100  polls the water level sensor at step  312 . If the water level sensor is greater than zero, meaning that the sensor indicates a low water level, then a decision block is performed at step  314  and the valve control solid state relay at step  316  as well as an indication light is set to “On.” The loop continues at step  318 . If the water level sensor is not set to “On,” then the loop continues to poll the water level sensor while the power is on.