Abstract:
A method and apparatus for surface treatment of footwear, bags, gloves, other leather items or leather-like items. The method includes optional covering a surface or a part of the items which are not to be treated; optional selecting time of operation of a spraying unit; placing items to be treated in a chamber; shutting the chamber and thereby manually or automatically initiating; activating the spraying unit for forming a mist of impregnating agent inside the chamber for applying impregnating agent onto the surfaces of the items; activating an air pump, ventilator or corresponding means for removal of excess impregnating agent from the chamber; and retaining excess impregnating agent in a filter which preferably is a filter containing activated carbon.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention concerns a method for impregnating items, for example footwear, bags, gloves, other leather items or leather-like items. The invention also concerns an apparatus for performing the method according to the invention. 
     2. Description of the Prior Art 
     When buying footwear and other leather items it has almost become common also to buy a spray can with a suitable impregnating agent. In the purchasing situation, it is not always remembered if a corresponding impregnating agent is already present at home, often resulting in a wrong purchase such that in many homes a number of spray cans with greater or lesser content of impregnating agent accumulate. 
     Storing of spray cans with impregnating contents may in practice imply a serious environmental problem because the spray cans cannot be discarded together with refuse collection and require handing in to recycling stations. 
     Moreover, the use of spray cans with impregnating agent or, for that matter, other contents is an unfavourable environmental factor due to the propellant being released to the atmosphere through the use thereof. 
     Thus it is expected that within a measurable time, a ban will be imposed on the use of spray cans containing a mixture of harmful propellant and inter alia impregnating agents. 
     SUMMARY OF THE INVENTION 
     The invention is a method and an apparatus which by means of simple technical measures enables elimination of the above mentioned drawbacks by surface treatment or impregnation of the items mentioned in the introduction, such as footwear. 
     A method for surface treatment of footwear, bags, gloves, other leather items or leather-like items comprises the following method steps: 
     possible covering a surface or a part of items not to be treated; 
     possible selecting time of operation of a spraying unit; 
     placing items to be treated in a chamber; 
     shutting the chamber and thereby manually or automatically initiating the following further method steps; 
     activating the spraying unit for forming a mist of impregnating agent inside the chamber for applying the impregnating agent onto surfaces of the items; 
     activating an air pump, ventilator or corresponding means for removal of excess impregnating agent from the chamber; and 
     retaining excess impregnating agent in a filter, which is preferably a filter containing activated carbon. 
     In a simple way and by means of simple technical measures it hereby becomes possible to eliminate the above-mentioned drawbacks that otherwise occur in connection with surface treatment by impregnation of footwear and other leather items. 
     As an alternative to the usual home impregnation of footwear, according to the invention it is possible already, for example, in a shoe shop to provide an optimal surface treatment of spraying footwear with a specific impregnation agent. 
     According to the invention the method may comprise the following further process steps: 
     selecting an impregnating agent; and 
     adjusting nozzles of the spraying unit in dependence on size and shape of actual items. 
     With the object of also treating items that cannot stand in the chamber by themselves, the method according to the invention may advantageously include the following additional method steps: 
     suspending items to be surface treated and which cannot stand by themselves in the chamber; and/or 
     supporting items with substantial height, such as boots, in upright position, for example, by means of internal supports in the bootlegs. 
     The invention also concerns an apparatus for impregnating items, comprising a closed chamber, at least one storage container for specific impregnating agents, the at least one storage container being connected with an electric pump via a valve system comprising at least one valve, wherein the pump is connected with at least one atomizing nozzle in the chamber, an electronic control unit for activating the pump and the valve system for connecting the pump and valve system with a storage container containing a specific impregnating agent, a filter and an air pump, ventilator or corresponding means for establishing a vacuum in the chamber for removal of residual impregnating agent from the chamber by retaining the residue in the filter. 
     For optimizing the surface treatment and minimizing use of impregnating agent, the apparatus according to the invention includes a scanner, a camera or other means for determining the shape and size of items disposed in the chamber and which, coordinated by the control, activates specific atomizing nozzles. 
     The apparatus according to the invention moreover includes means for supporting elongated items, by way of example high boots, either upright or hanging in the chamber. 
     Advantageously, the apparatus according to the invention may includes a drawer arranged under the chamber. The drawer is preferably accessible from the front side of the apparatus and contains the filter and optionally also the storage containers for impregnating agents. 
     To facilitate access from the spraying chamber, the chamber may include a sliding door which opens upwardly and preferably includes an electrical actuating mechanism. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The invention is now explained in detail in connection with the drawing, in which: 
         FIG. 1  shows a plan view of an embodiment of an apparatus according to the invention, as seen from the front side thereof; 
         FIG. 2  shows a plan view of the apparatus of  FIG. 1  which is seen from the right side; 
         FIG. 3  shows a plan view of the apparatus of  FIG. 1  which is seen from the front and with the chamber being open; 
         FIG. 4  shows a plan view of the apparatus of  FIG. 1  which is seen from the left side; 
         FIG. 5  shows a plan view of the apparatus of  FIG. 1  which is seen from above; 
         FIG. 6  shows a plan view of the apparatus of  FIG. 2  which is shown with an open drawer; 
         FIG. 7  shows a plan view of a second embodiment of an apparatus according to the invention which is seen from the front side thereof; 
         FIG. 8  shows a plan view of the apparatus of  FIG. 1  which is provided with legs; 
         FIG. 9  shows a plan view of the apparatus of  FIG. 2  which is provided with legs; and 
         FIG. 10  shows a perspective “transparent” view of a preferred embodiment of an apparatus according to the invention which is seen obliquely from behind; 
         FIG. 11  shows a plan view of the apparatus of  FIG. 10  which is seen from the side; 
         FIG. 12  shows a perspective view corresponding to  FIG. 10  which is shown with an upper drawer in the open position for inserting items to be impregnated; 
         FIG. 13  shows a plan view corresponding to  FIG. 12 ; and 
         FIG. 14  shows a simplified perspective view of the preferred apparatus according to the invention shown in  FIGS. 10-13 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The apparatus  2  shown in  FIGS. 1-6  is designed as a generally box-shaped cabinet  4  with a front door in the form of a sliding door  6  ( FIG. 3 ) and with a lower drawer  8  with a front  10 . The cabinet  4  includes an internal spraying chamber  12  with a plane bottom plate  14  upon which items to be surface treated can be supported. 
     When the sliding door  6  is opened, as shown in  FIG. 3 , by an operating button  16 , a display  18 , which by way of example has three pushbuttons  20 ,  22  and  24  becomes accessible for selecting a specific impregnating agent. 
     After preselection by pressing one of the pushbuttons  20 ,  22  and  24 , the sliding door  6  is closed and the apparatus  2  is started by renewed pressing on the operating button  16 . That is, the impregnation treatment is initiated as soon as the sliding door  6  has been closed. During operation of the apparatus  2 , the operating button  16  will preferably be illuminated and inactive. It is to be inoperative for pressure action. 
     At the end of impregnation treatment, the time period of which can be fixedly pre-selected or adjustable, an air pump, ventilator or similar means integrated in the bottom of the cabinet  4 , which is preferably behind the drawer  8 , will automatically started and establishes a vacuum in the spraying chamber  12  causing the residual impregnating agent to be exhausted through a filter, which preferably contains activated carbon, that is, by way of example, incorporated in the drawer  8 . The drawer  4  preferably has less depth than the depth of the cabinet  4 , which appears from  FIGS. 4 and 6 .  FIG. 4  further shows an exhaust opening  26  of the air pump, ventilator or the like disposed behind the drawer  8 . 
     The drawer  8  may, as indicated, also have space for, by way of example, three storage containers for impregnating agent. As shown additionally in  FIGS. 2, 6 and 8 , the drawer  8  is provided with a key operated lock  28  as the drawer  8  is normally only to be opened by certified personnel.  FIGS. 8 and 9  show the apparatus  2  provided with legs  30  so that the cabinet  4  is located at a working level which is comfortable for staff. 
       FIG. 7  shows an alternative embodiment of an apparatus  32  which includes a left-hinged pivoting door  34  and a display  36  having an associated operating panel  38  with pushbuttons  42 ,  44  and  46 . 
       FIGS. 10-14  show a preferred embodiment of an apparatus  48  where a bottom plate  50  and an upper front door  52  of the spraying chamber  12  a sliding drawer  54  which, as shown in  FIGS. 12 and 13 , can be drawn out for making space for lateral insertion of items in the spraying chamber  12 . The bottom plate  50  is made of a perforated plate  56  which is a form connection via an upper pleated drop filter  58  for a cubic filter cassette  60  preferably filled with activated carbon. The drop filter with  58  is disposed immediately under the spraying chamber  12  in a compartment  62  having access through a lower front door  64 . 
     In the compartment  64  immediately under the filter box  60 , a vacuum source which may be an air pump or ventilator  66  is placed, providing exhaust of excess impregnating liquid through the filter cassette  60 . The vacuum source communicates with the surroundings through a lower ventilation opening  68  at the bottom of the apparatus  48 . 
     When the filter cassette  60  containing the upper drop filter  58 , after impregnating about 6,600 pairs of shoes and consuming 37-42 liters of impregnation liquid, is to be replaced, the lower front door  64  is opened, after which the filter cassette  60  is removal by downward movement by a pivot arm mechanism  70  via a transverse operating handle  73 , such that the used filter cassette  60  can be removed and replaced by a corresponding new filter cassette  60 . 
     In  FIG. 11 , the handle  73  is turned down from the position in  FIG. 13  which releases, the filter cassette  60  from contact with the bottom plate  50  to provide a spacing between the filter cassette  60  and the bottom plate  50  to permit removal of the filter cassette  60 . The filter cassette  60  in  FIG. 13  is shown in its upper operational situation when the filter cassette  60  contacts the bottom plate  50  to provide a connection between the bottom plate and the filter cassette. 
     With the object of protecting or facilitating cleaning the inner walls and the bottom plate  50  of the spraying chamber  12 , advantageously there may be applied an internal covering of a reticulated polyurethane foam with a PPI (pore per inch) of about 70-80, by way of example of the type Regicell 80 HIFI Black which has a density of about 30 kg/m 3 . 
     The covering of the bottom plate  50  only influences the air penetration of the perforated bottom plate  50  ( FIG. 14 ) to a very small degree. Under normal operational conditions, the internal covering is to be replaced more often than the filter cassette  60  which, by way of example, is about every 2,000 impregnation treatments. 
     In a prototype version of the apparatus  48  according to the invention, the filter cassette  60  was made of MDF-board. For future filter cassettes  60 , the cassette itself can be made of a considerably lighter material which, by way of example, is fiber cardboard. In that regard it is important to note that used filter cassettes  60  are completely harmless and may be disposed of together with refuse collection. 
     The applied impregnating liquid is particularly developed for impregnating shoes, gloves, clothing etc. The impregnating liquid is quick-drying and hardens in the course of about 90 seconds at 20° C. The impregnating liquid does not cause discoloration, spots or blotches. The impregnation liquid secures the fabric against bleaching by sunlight, attacks by fungus, mildew and fungus mould. The impregnation liquid can be used on oiled clothing of nylon/rayon and make it completely tight. 
     In the preferred embodiment of an apparatus  48  according to the invention shown in  FIGS. 10-14 , the apparatus is provided with a jacket  76  of stainless steel sheeting which in one piece constitutes the outer rear and side walls. With this configuration, there is only access to the interior of the apparatus through the upper and lower front doors  52  and  64 . 
     At least one storage container of impregnating liquid is located in a lower L-shaped box  74  behind and under the filter cassette  60 . A pump  71  and diverse supply connections are located behind a stationary rear sheet  70  of the spraying chamber  12  from which atomizing nozzles  72  protrude into the spraying chamber  12 . 
     The processing time is about 25 seconds in total to complete treatment of an item. The atomization treatment for coating an item takes 800 milliseconds with about 20 seconds being used for drying the treated item. The ventilator  66  has a capacity of about 100 m 3 /h and the exhaust from the spraying chamber  12  provides a complete air exchange of 1.5 seconds. The interval between treatments is about 4 seconds. 
     The specific arrangement of the spraying chamber  12  may vary according to need, depending on the actual items to be impregnated by means of the apparatus  2 ,  32  and  48 . 
     For example, the spraying chamber  12  may be equipped with a number of atomizing nozzles that have a mutually fixed disposition, or the mutual disposition of which may be varied. Another possibility is equipping the spraying chamber  12  with movable atomizing nozzles if the actual pattern of movement is determined by the actual shape and size of the actual item to be impregnated.  FIG. 11  illustrates a camera, a scanner or other means  84  for determining the shape and size of items disposed in the chamber. 
     As also indicated, the spraying chamber  12  may be equipped with devices or means  82  as shown in  FIG. 13  for suspending or in other ways reinforcing items that either cannot stand by them selves or which have substantial height, such as high boots. 
     A very significant future application of the method and apparatus according to the invention is for impregnating treatment of clothing, particularly hunting clothes, leisure clothing, ski clothing, children&#39;s clothing, including snowsuits for children. 
     In the performing of the present invention, additional future applications are expected, such as antiseptic treatment of bowling shoes (shoes for rent or lending) and antiseptic treatment of summer footwear, in particular sandals. 
     The present invention is may be used such that the method and apparatus according to the invention are primarily used in specialty stores for footwear and leather items. Apparatuses are set up according to a co-operation agreement (franchise) and serviced by a firm that owns and sets up the apparatuses (impregnation machines). In other words, the individual user or business preferably pays a fixed fee determined by a set number of treatments and possibly by the type of treatment, as it is presumably to be more expensive for treating a pair of high boots than a pair of shoes. 
     The apparatus of the invention has an external counter or a display which is read in connection with payment, and which according to prior art by way of example can be remotely read. Alternatively, the apparatus can be adapted to communicate with a service firm via SMS or other wireless communication to provide remote controlled reading. 
     When buying footwear or other leather items, that normally are to be impregnated afterwards with use of the invention, it should be a standard situation that the shop assistant in connection with a purchase will ask, “should I impregnate the shoes”, “should I impregnate the boots” or “should I impregnate the bag?” 
     Finally, it is to be noted that an impregnating apparatus of the invention may be used as in a slot-machine version for setup in hotels, shopping centers, train and bus stations or other public localities.