Abstract:
An apparatus and a method for dispensing a wash solution, conveyed into a washing device, at a desired concentration of detergent chemical. The apparatus includes a first tank for a wash solution at a desired concentration. Supply water passed through measuring elements is divided into partial flows along at least two lines. At least one line conveys detergent chemical along with water into the tank, and at least one second line supplies plain water. The apparatus includes at least one second tank, into which at least a detergent chemical-containing partial flow is conveyed into the first tank. The second tank has a first surface level sensing element which indicates the attainment of a design volume and the amount of water which has flown through the measuring elements at the indication moment and which provides a basis for determining the concentration of detergent chemical in the second tank.

Description:
CROSS-REFERENCED TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of PCT Patent Application No. PCT/FI2015/050567 filed Sep. 1, 2015, which claims the benefit under 35 USC §119(e) to Finnish Patent Application No. 20145791, filed Sep. 11, 2014, the disclosure of each of these applications are expressly incorporated herein by reference in their entireties. 
     
    
     FIELD 
       [0002]    The present invention relates to an apparatus for dispensing a wash solution for conveying the same into a washing device, said apparatus comprising a first tank for the wash solution, said tank including elements for supplying the tank with wash water and a wash solution, elements for measuring the amount of water to be supplied into the tank, and elements for conveying the wash solution from the tank into the washing device. The invention relates also to a car wash facility. In addition, the invention relates to a method for dispensing a wash solution, made up of water and a detergent chemical and to be conveyed into a washing device, at a desired concentration of detergent chemical. A still further object of the invention is a program media. 
       BACKGROUND 
       [0003]    The current problems with car wash facilities include, among others, different wash solution concentration requirements for winter and summer seasons, which require manual adjustment procedures with resulting considerable costs. In addition, it is difficult with current systems to uphold the concentration of a wash solution due, among other things, to pressure fluctuations in the service water of each car wash facility and problems in systems warning about depleting chemical containers. Therefore, it is necessary in car wash facilities from time to time to conduct manual verifying measurements by means of a measuring cup to find out how the adjustments have held. 
         [0004]    Thus, it is an object of the present invention to provide a reliable apparatus for dispensing a wash solution at a desired detergent concentration into a washing device. In order to attain this objective, an apparatus of the invention is characterized by what is presented in the characterizing section of claim  1 . A car wash facility of the invention is characterized by what is presented in the characterizing section of the independent claim  6 . A method of the invention is in turn characterized by what is presented in the characterizing section of the independent claim  7 . A program media of the invention is characterized by the characterizing features presented by the independent claim  13 . 
     
    
     
       DRAWINGS 
         [0005]    The invention will now be described more closely with reference to the accompanying drawings, in which: 
           [0006]      FIG. 1  shows in a schematic view of principle one exemplary embodiment for an apparatus of the invention, 
           [0007]      FIG. 2  shows one component for an apparatus of the invention in more detail in a schematic isometric view, and 
           [0008]      FIG. 3  shows one optional embodiment for the component of  FIG. 2  in a schematic side view. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]      FIG. 1  shows schematically one implementation example for an apparatus  1  of the invention. The apparatus includes a first tank  8 , which is used for holding a wash solution at a specific detergent concentration for conveying the same via a pipe  11  by means of a pump  12  into a washing device (not shown), which is for example a car washing device, and which is supplied with the wash solution intermittently according to a desired wash program. For various wash solutions there are provided specific dispensers, e.g. separate ones for waxing wash and solvent wash. Inside the holding tank  8  is fitted a second tank  7  which is provided with siphon means  13 . The wash solution is produced by supplying water through a flow meter  2  and by dividing the flow into partial flows along lines  3  and  4 , which are provided with magnetic valves  5  and  6 , respectively. By controlling the valves  5  and  6 , it is possible to determine the ratio and time instant for the partial flows. Downstream of the valve, each line continues to the second tank  7  as line sections  18  and  19 , respectively. The valve  6  is equipped with a nozzle member (not shown), which operates on ejector principle drawing in detergent from a chemical tank  9  via a pipe  10  as water is supplied through the nozzle at a suitable pressure. The nozzle member is designed to draw in the detergent chemical at a constant ratio with respect to water supplied by way of the valve  6 , for example 1 part of detergent chemical and 2 parts of water, whereby the wash solution passing along the line section  19  downstream of the valve  6  contains about 33% of detergent chemical. The detergent chemical can be in the form of a concentrate or previously admixed in water to a certain concentration, which is diluted with water in the siphon-containing tank  7  and/or in the holding tank  8 . The second tank  7  is provided with a surface level sensing element  16 , which is set to indicate the attainment of e.g. a 1 liter design volume in the second tank  7 . The sensing element  16  comprises preferably an electrically conductive static measuring stick, which provides a signal upon coming to contact with liquid. When the sensing element  16  issues a signal about the attainment of 1 liter design volume, the flow meter  2  will be read for the amount of water that has passed therethrough, thereby enabling the amount of detergent chemical picked up from the chemical tank  9  to be calculated by subtracting the measured amount of water from the volume of  11 . Once the concentration of detergent chemical in the tank  9  is known, this provides a reliable and relatively simple way of determining its concentration in a final wash solution in the tank  8 . The second tank  7  is provided with a siphon  13 , which enables a delivery of the wash solution into the first tank  8  as soon as the detergent chemical-containing solution has reached a volume required for activating the siphon in the second tank  7 . The volume needed for activating the siphon is preferably slightly larger than the design volume, e.g. 1.2 liters. 
         [0010]      FIG. 2  shows separately one exemplary embodiment for the second tank  7  in slightly more detail. One edge of the tank is formed with an overflow brim  14  slightly lower than the rest of the tank&#39;s edge. The siphon  13  is in this example adapted to open at one of its ends to the proximity of a floor of the tank  7  for enabling the tank to be emptied essentially completely by means of the siphon. The siphon has its other end extended through the floor of the tank  7 . 
         [0011]    The concentration of a detergent chemical in the wash solution can be determined e.g. at the start of each washing process as the sensing element  16  issues a signal about the attainment of a design volume in the second tank  7 , followed by supplying water via the lines  3 ,  18  and  4 ,  19  continuously into the second tank  7 , wherefrom the wash solution flows by way of both the siphon  13  and the overflow brim  14  into the first tank. The supply of water via the lines  3 ,  18  and  4 ,  19  in a continuous manner takes place at a certain ratio between partial flows which can be adjusted as necessary. The adjustment is preferably adapted to enable remote control by connecting the flow meter  2 , the magnetic valves  5 ,  6 , and the sensing element  16  to a remote control system. Thereby, it is also possible to produce alarms about various fault conditions. The continuous supply is carried on until the washing process comes to an end, at which time the second tank drains by way of the siphon. After the next washing process has started and the tank is filling up, there will be conducted another determination of concentration. 
         [0012]    According to one option, the concentration can be determined in such a way that the second tank  7  is emptied by means of the siphon  13  always after the concentration has been determined by supplying the second tank  7  with a detergent chemical-containing partial flow and a partial flow of solely water until the siphon  13  activates. After the draining, the second tank is refilled and the process is repeated, whereby the concentration of detergent chemical in each batch is known precisely and, therefore, so is also the concentration of a wash solution present in the first tank  8 . 
         [0013]    The first tank  8  is provided with a second surface level sensing element  15 , which indicates the attainment of a given design volume of wash solution in the first tank. The sensing element  15  comprises preferably an electrically conductive static measuring stick, which provides a signal upon coming to contact with liquid. This second sensing element  15  can also be utilized in the determination of a detergent chemical concentration, e.g. by adapting the second tank  7  to be only supplied with a detergent chemical-containing partial flow and the first tank  8  directly with a partial flow containing just water. By means of the sensing element  16  of the second tank  7  it is possible to determine the chemical concentration of a wash solution fraction present in the second tank by only feeding water initially through the magnetic valve  6  of the second line  4  while the valve  5  is closed. Once the chemical concentration in the second tank is determined, the second tank  7  shall still be supplied with a detergent chemical-containing partial flow of water required for the siphon  13  to activate. After the siphon  13  has been activated, the magnetic valve  6  will be closed and the magnetic valve  5  will be opened, whereby the first tank  8  will be supplied with water along the line  18  until the second sensing element  15  issues a signal about the attainment of a design volume in the first tank  8 . The supply of water through the magnetic valve  5  is timed in such a way that the draining of the second tank  7  by means of the siphon  13  takes place prior to reaching a design volume in the first tank  8 . 
         [0014]    The first tank  8  has its upper part region, above the second tank  7 , preferably provided with a third surface level sensing element  17 , which is used for ensuring that the apparatus is not allowed to overflow. The sensing element  17  comprises preferably an electrically conductive static measuring stick, which provides a signal upon coming to contact with liquid. When the third sensing element  17  issues a signal about reaching an overflow alarm threshold, the supply of water is stopped immediately, e.g. by closing the magnetic valves  5  and  6 . 
         [0015]    In the foregoing embodiment, the siphon  13  has such a disposition that, after its activation, there is achieved a substantially complete draining of the second tank  7 , but the siphon can also be disposed in a top edge region of the second tank as shown in  FIG. 3 , whereby the tank&#39;s design volume will be defined as the volume of a space V m  between a bottom edge of an intra-tank part of the siphon  13  and a bottom edge of the sensing element  16 . Thus, it is possible that the second tank has continuously some wash solution, which is present in a zone below a bottom edge of the siphon  13  and the concentration of which has been adjusted as desired by supplying the second tank with a mixture of detergent chemical and water at a correct ratio for as long as the entire wash solution volume has been exchanged. 
         [0016]    In the foregoing embodiment, inside the first tank  8  is disposed one second tank  7  equipped with a siphon  13 , but there can be several of such second tanks within the first tank, e.g. a specific one for various detergent chemicals, whereby the supply of water may also take place along several lines as may be required by a particular detergent chemical. Plain water may also has its siphon-equipped designated tank, by means of which the flow meter can be easily calibrated by propelling plain water into the siphon-containing tank and, as the sensing element issues a signal about the attainment of a design volume, the reading given by the flow meter is checked at the same instant and the flow meter is adjusted as necessary to indicate the real design volume. The siphon-containing tanks can also be connected to each other, e.g. such that the detergent chemical-containing tank is emptied by means of the siphon into another siphon-containing tank to which opens a plain water supply line. This way is achieved effective mixing and the mixture is then conducted by means of the siphon into the first tank  8 . 
         [0017]    With a view to emptying a siphon-containing tank more effectively, the tank can be provided with more than one siphon, which can be disposed at various activation heights. 
         [0018]    The control system for an apparatus of the invention can be implemented in a way controlled by a computer, whereby different adjustments, needed e.g. in car wash facilities in various seasons, can be carried out e.g. by making a program code which complies with the calendar in terms of adjusting the concentration little by little from a lower concentration needed in summer to a higher concentration needed in winter and again back towards a lower concentration. Typically, the detergent chemical concentration is in the order of about 5% in summer and in the order of about 30% in winter. In traditional systems, the adjustment has been made by manually swapping different size nozzles in the autumn for a winter setup and others in the spring for a summer setup. This entails that it is often necessary to run even long periods with wrong setups before managing to exchange the nozzles for a size appropriate for the season. In the autumn, this entails a poorer wash result as the concentration of a detergent chemical falls short of what is necessary in light of the conditions and in the spring, on the other hand, the consumption of a detergent chemical becomes excessive in light of the demand, thus incurring extra costs for the car wash facility. In addition, the manual swapping of nozzles leads to considerable maintenance costs and use of time for the personnel conducting the exchange. 
         [0019]    Benefits of the foregoing invention are, among others, as follows:
       detergent chemical concentration can be determined dependably and in a reliably working manner   determination of concentration and necessary corrections to concentration and changes of concentration, e.g. according to various seasons, can be conducted in a computer-controlled manner and by making use of remote control   moving actuators are not in contact with detergent chemical, thus reducing the need for maintenance   more attractive price as compared to solutions implemented by means of various control valves   no need for on-site exchange of nozzles according to various seasons   homogenizes the concentration, preventing its fluctuation   improves mixing of the material   prevents reflux into the chemical tank   enables a compact assembly   quick maintenance   reduces substantially the operating time of magnetic valves, thus increasing the longevity thereof   no moving parts in contact with detergent chemical.       
 
         [0032]    Although the invention has been described above specifically in relation to car wash facilities, it is applicable also to other corresponding washing plants, such as washing facilities for trains, washing equipment for various industrial plants (e.g. meat packing companies), etc. 
       LIST OF REFERENCE NUMERALS 
       [0033]      1  dispenser
 
 2  water meter
 
 3 ,  4  water supply
 
 5  magnetic valve
 
 6  magnetic valve and ejector
 
 7  siphon-equipped tank
 
 8  wash liquid mixture holding tank
 
 9  tank for detergent chemical
 
 10  detergent chemical supply pipe
 
 11  outlet pipe from wash liquid mixture tank
 
 12  pump
 
 13  siphon
 
 14  siphon tank&#39;s overflow brim
 
 15 - 17  surface level sensing elements
 
 18  water supply into siphon tank
 
 19  wash solution supply into siphon tank V m  design volume